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33,480 Abstracts & Growing Daily. Sourced from the US National Library of Medicine.


Caffeic acid phenethyl ester augmented tamoxifen cytotoxicity via multiple mechanisms.

Although Tamoxifen (TAM) is one of the most widely used drugs in managing breast cancer, many women still relapse after long-term therapy. Caffeic acid phenethyl ester (CAPE) is a polyphenolic compound present in many medicinal plants and in propolis. The present study examined the effect of CAPE on TAM cytotoxicity in MCF-7 cells. MCF-7 cells were treated with different concentrations of TAM and/or CAPE for 48 h. This novel combination exerted synergistic cytotoxic effects against MCF-7 cells via induction of apoptotic machinery with activation of caspases and DNA fragmentation, along with downregulation of Bcl-2 and Beclin 1 expression levels. However, the mammalian microtubule-associated protein light chain LC 3-II level was unchanged. Vascular endothelial growth factor level was also decreased, whereas levels of glutathione and nitric oxide were increased. In conclusion, CAPE augmented TAM cytotoxicity via multiple mechanisms, providing a novel therapeutic approach for breast cancer treatmentthat can overcome resistance and lower toxicity. This effect provides a rationale for further investigation of this combination.

Oxid Med Cell Longev. 2016 ;2016:3017108. Epub 2015 Nov 30. PMID: 26697130


A review of walnut polyphenols in health maintenance and disease prevention.

Walnuts are commonly found in our diet and have been recognized for their nutritious properties for a long time. Traditionally, walnuts have been known for their lipid profile which has been linked to a wide array of biological properties and health-promoting effects. In addition to essential fatty acids, walnuts contain a variety of other bioactive compounds such as, vitamin E and polyphenols. Among common foods and beverages, walnuts represent one of the most important sources of polyphenols, hence, their effect over human health warrants attention. The main polyphenol in walnuts is pedunculagin, an ellagitannin. After consumption, ellagitannins are hydrolyzed to release ellagic acid, which is converted by gut microflora to urolithin A and other derivatives, such as urolithins B, C and D. Ellagitannins possess well known antioxidant and anti-inflammatory bioactivity and several studies have assessed the potential role of ETs against disease initiation and progression, including cancer, cardiovascular and neurodegenerative diseases. The purpose of this review is to summarize current available information relating to the potential effect of walnut polyphenols in health maintenance and disease prevention.

Crit Rev Food Sci Nutr. 2015 Dec 29:0. Epub 2015 Dec 29. PMID: 26713565


Chemoprevention of breast cancer by dietary polyphenols.

The review will discuss in detail the effects of polyphenols on breast cancer, including both the advantages and disadvantages of the applications of these natural compounds. First, we focus on the characterization of the main classes of polyphenols and then on in vitro and in vivo experiments carried out in breast cancer models. Since the therapeutic effects of the administration of a single type of polyphenol might be limited because of the reduced bioavailability of these drugs, investigations on combination of several polyphenols or polyphenols with conventional therapy will also be discussed. In addition, we present recent data focusing on clinical trials with polyphenols and new approaches with nanoparticles in breast cancer. Besides the clinical and translational findings this review systematically summarizes our current knowledge about the molecular mechanisms of anti-cancer effects of polyphenols, which are related to apoptosis, cell cycle regulation, plasma membrane receptors, signaling pathways and epigenetic mechanisms. At the same time the effects of polyphenols on primary tumor, metastasis and angiogenesis in breast cancer are discussed. The increasing enthusiasm regarding the combination of polyphenols and conventional therapy in breast cancer might lead to additional efforts to motivate further research in this field.

Molecules. 2015 ;20(12):22578-620. Epub 2015 Dec 17. PMID: 26694341


Experimental data supports the bright future of natural polyphenols as anticancer tools.

Cancer onset and progression have been linked to oxidative stress by increasing DNA mutations or inducing DNA damage, genome instability, and cell proliferation and therefore antioxidant agents could interfere with carcinogenesis. It is well known that conventional radio-/chemotherapies influence tumour outcome through ROS modulation. Since these antitumour treatments have important side effects, the challenge is to develop new anticancer therapeutic strategies more effective and less toxic for patients. To this purpose, many natural polyphenols have emerged as very promising anticancer bioactive compounds. Beside their well-known antioxidant activities, several polyphenols target epigenetic processes involved in cancer development through the modulation of oxidative stress. An alternative strategy to the cytotoxic treatment is an approach leading to cytostasis through the induction of therapy-induced senescence. Many anticancer polyphenols cause cellular growth arrest through the induction of a ROS-dependent premature senescence and are considered promising antitumour therapeutic tools. Furthermore, one of the most innovative and interesting topics is the evaluation of efficacy of prooxidant therapies on cancer stem cells (CSCs). Several ROS inducers-polyphenols can impact CSCs metabolisms and self-renewal related pathways. Natural polyphenol roles, mainly in chemoprevention and cancer therapies, are described and discussed in the light of the current literature data.

Oxid Med Cell Longev. 2016 ;2016:6475624. Epub 2015 Nov 16. PMID: 26649142


Turkish propolis is capable of reducing cancer cell proliferation in A549 cells.

Cancer is a heterogeneous disease, two of whose characteristic features are uncontrollable cell proliferation and insufficient apoptosis. Various studies have investigated the antiproliferative effects of propolis, a natural bee product, from different countries, and its cytotoxic effects have been attributed to its polyphenol contents. The purpose of this study was to show the cytotoxic effects, and possible mechanisms involved, of ethanolic extract of Turkish propolis (EEP) on the human lung cancer (A549) cell line. Cytotoxic activity of EEP on A549 cells was revealed using the MTT assay. Mechanisms involved in the cytotoxic action of EEP on A549 cells were then investigated in terms of apoptosis, mitochondrial membrane potential and cell cycle using flow cytometry, endoplasmic reticulum stress using RT-PCR, and caspase activity using luminometric analysis. EEP exhibited selective toxicity against A549 cells compared to normal fibroblast cells. We determined that EEP arrested the cell cycle of A549 cells at the G1 phase, induced endoplasmic reticulum stress, caspase activity, and apoptosis and reduced mitochondrial membrane potential. These results indicate that Turkish propolis is capable of reducing cancer cell proliferation and may have a promising role to play in the development of new anticancer drugs in the future.

Nutr Cancer. 2015 Dec 23:1-8. Epub 2015 Dec 23. PMID: 26700423


In this review, the mechanism of anticancer effect of curcumin in GBM has been discussed extensively.

GBM (Glioblastoma) is the most malignant human brain tumor with median survival of one year. The treatment involves surgery, radiotherapy and adjuvant chemotherapy mostly with the alkylation agents such as temozolomide (TMZ). Dietary polyphenol curcumin, isolated from the rhizome of the Curcuma longa (turmeric), has emerged as remarkable anti-cancer agent in the treatment of various peripheral cancers such as blood, lymphomas, multiple myeloma, melanoma as well as skin, lung, prostate, breast, ovarian, bladder, liver, gastrointestinal tract, pancreatic and colorectal epithelial cancers with a pleiotropic mode of action and also showed promise in alleviation of GBM. In this review, the mechanism of anticancer effect of curcumin in GBM has been discussed extensively. The clinical safety and pharmacokinetics of curcumin has been scrutinized to combat the challenges for the treatment of GBM.

Eur J Med Chem. 2015 Dec 15 ;109:23-35. Epub 2015 Dec 15. PMID: 26748069


The molecular mechanisms of curcumins suppressive effects on tumorigenesis, angiogenesis and metastasis, focusing on NF-κB pathway.

NF-κB pathway has long been considered as one of the potent prototypical pro-inflammatory signaling pathway and its role in several aspects of human health has been established. Recent studies have suggested that NF-κB activation is the master key in early development and pathobiology of several Cancers. Curcumin is a polyphenolic phytochemical compound with several stablished anti-inflammatory properties and is known to exert its anti-inflammatory effects mostly by interrupting NF-κB signaling pathway at multiple stages. Here we tried to provide a summary of recent finding, focusing on introducing NF-κB signaling pathways and its potential mechanism involved in development of several types of Cancers.

Cytokine Growth Factor Rev. 2016 Jan 2. Epub 2016 Jan 2. PMID: 26774676


This review explores the full potential of resveratrol in breast cancer prevention and treatment.

Globally, breast cancer is the most frequently diagnosed cancer among women. The major unresolved problems with metastatic breast cancer is recurrence after receiving objective response to chemotherapy, drug-induced side effects of first line chemotherapy and delayed response to second line of treatment. Unfortunately, very few options are available as third line treatment. It is clear that under such circumstances there is an urgent need for new and effective drugs. Phytochemicals are among the most promising chemopreventive treatment options for the management of cancer.Resveratrol (3,5,4'-trihydroxy-trans-stilbene), a non-flavonoid polyphenol present in several dietary sources, including grapes, berries, soy beans, pomegranate and peanuts, has been shown to possess a wide range of health benefits through its effect on a plethora of molecular targets.The present review encompassesthe role of resveratrol and its natural/synthetic anlogues in the light of their efficacy against tumor cell proliferation, metastasis, epigenetic alterations and for induction of apoptosis as well as sensitization towards chemotherapeutic drugs in various in vitro and in vivo models of breast cancer. The roles of resveratrol as a phytoestrogen, an aromatase inhibitor and in stem cell therapy as well as adjuvent treatment are also discussed. This review explores the full potential of resveratrolin breast cancer prevention and treatment with current limitations, challenges and future directions of research.

Semin Cancer Biol. 2016 Jan 13. Epub 2016 Jan 13. PMID: 26774195


The combination of curcumin, EGCG and arctigenin synergistically enhanced the anti-proliferative effects in both prostate and breast cancer cells.

The low bioavailability of most flavonoids limits their application as anti-carcinogenic agents in humans. A novel approach of treatment with a mixture of bioactive compounds that share molecular anti-carcinogenic targets may enhance the effect on these targets at low concentrations of individual compound, thereby overcoming the limitations of reduced bioavailability. We therefore investigated whether a combination of three natural products arctigenin (Arc), a novel anti-inflammatory lignan from the seeds of Arctium lappa, green tea polyphenol (-)-epigallocatechin gallate (EGCG) and curcumin (Cur) increases the chemopreventive potency of individual compounds. LNCaP prostate cancer and MCF-7 breast cancer cells were treated with 2-4 mg/L (about 5-10μM) Cur, 1μM Arc and 40μM EGCG alone or in combination for 48h. In both cell lines treatment with the mixture of Cur, Arc and EGCG synergistically increased the antiproliferative effect. In LNCaP cells both Arc and EGCG increased the pro-apoptotic effect of Cur. Whereas in MCF-7 cells Arc increased the cell apoptosis of Cur while EGCG enhanced cell cycle arrest of Cur at G0/G1 phase. The strongest effects on cell cycle arrest and apoptosis were achieved by combining all three compounds in both cell lines. The combination treatment significantly increased the ratio of Bax to Bcl-2 proteins,decreased the activation of NFκB, PI3K/Akt and Stat3 pathways and cell migration compared to individual treatment. These results warrant in vivo studies to confirm the efficacy of this novel regimen by combining Arc and EGCG with Cur to enhance chemoprevention in both prostate and breast cancer.

RSC Adv. 2014 Aug 5 ;4(66):35242-35250. PMID: 25243063


Pelingo apple is rich in food components that can markedly inhibit in vitro tumorigenesis and growth of human breast cancer cells.

PURPOSE: The aim of this study was to evaluate the antiproliferative activity in breast cancer cells and the inhibition of tumorigenesis in pre-neoplastic cells of a new apple cultivar with reddish pulp, called the Pelingo apple. METHODS: The antiproliferative activity was evaluated in MCF-7 and MDA-MB-231 human breast cancer cells. The inhibition of tumorigenesis was performed in JB6 promotion-sensitive (P+) cells. RESULTS: Results showed that Pelingo apple juice is characterized by a very high polyphenol content and strongly inhibited breast cancer cell proliferation. Its antiproliferative activity was found to be higher than the other five apple juices tested. Pelingo juice induced cell accumulation in the G2/M phase of the cell cycle and autophagy through overexpression of p21, inhibition of extracellular signal-regulated kinases 1/2 (ERK1/2) activity and an increase in lipidated microtubule-associated protein-1 light chain-3 beta (LC3B). Remarkably, Pelingo juice inhibited the 12-o-tetra-decanoyl-phorbol-13-acetate (TPA)-induced tumorigenesis of JB6 P+ cells, suppressing colony formation in semi-solid medium and TPA-induced ERK1/2 phosphorylation. CONCLUSIONS: Our data indicate that the Pelingo apple is rich in food components that can markedly inhibit in vitro tumorigenesis and growth of human breast cancer cells and could provide natural bioactive non-nutrient compounds, with potential chemopreventive activity.

PLoS One. 2015 ;10(8):e0135840. Epub 2015 Aug 18. PMID: 26284516


Resveratrol induces DNA damage in colon cancer cells by poisoning topoisomerase II.

Resveratrol (trans-3,4',5-trihydroxystilbene) is a natural polyphenol synthesized by various plants such as grape vine. Resveratrol (RSV) is a widely studied molecule, largely for its chemopreventive effect in different mouse cancer models. We propose a mechanism underlying the cytotoxic activity of RSV on colon cancer cells. Our data show that resveratrol induces apoptosis, as observed by the cleavage of PARP-1 and chromatin condensation. We show that the tumor suppressor p53 is activated in response to RSV and participates to the apoptotic process. Additionally, we show that HCT-116 p53 wt colon carcinoma cells are significantly more sensitive than HCT-116 p53-/- cells to RSV. RSV induces DNA damage including double strand breaks, as evidenced by the presence of multipleγ-H2AX foci in 50% of cells after a 24 h treatment with 25 μM RSV. The formation of DNA damage does not appear to rely on a pro-oxidant effect of the molecule, inhibition of topoisomerase I, or DNA intercalation. Rather, we show that DNA damage is the consequence of type II topoisomerase poisoning. Exposure of HCT-116 cells to RSV leads to activation of the Ataxia Telangiectasia Mutated (ATM) kinase, and ATM is required to activate p53.

Toxicol In Vitro. 2015 Aug ;29(5):1156-65. Epub 2015 May 5. PMID: 25952326


Resveratrol has potential as a supplemental therapy for the prevention of renal injury.

Resveratrol (RESV) is a polyphenolic compound found in various plants, including grapes, berries and peanuts, and its processed foods as red wine. RESV possesses a variety of bioactivities, including antioxidant, anti-inflammatory, cardioprotective, antidiabetic, anticancer, chemopreventive, neuroprotective, renal lipotoxicity preventative, and renal protective effects. Numerous studies have demonstrated that polyphenols promote cardiovascular health. Furthermore, RESV can ameliorate several types of renal injury in animal models, including diabetic nephropathy, hyperuricemic, drug-induced injury, aldosterone-induced injury, ischemia-reperfusion injury, sepsis-related injury, and endothelial dysfunction. In addition, RESV can prevent the increase in vasoconstrictors, such as angiotensin II (AII) and endothelin-1 (ET-1), as well as intracellular calcium, in mesangial cells. Together, these findings suggest a potential role for RESV as a supplemental therapy for the prevention of renal injury.

J Bras Nefrol. 2015 Jan-Mar;37(1):106-14. PMID: 25923757


Polyphenolic compounds from chaga mushroom had the ability to inhibit topoisomerase II.

Low molecular weight (LMW) polyphenolics containing a polyhydroxylated benzyl moiety are abundant in medicinal plants. In the present study, we report on the activities of seven LMW polyphenolics isolated from Inonotus obliquus, a medicinal mushroom. The isolated compounds included caffeic acid (CA), 3,4-dihydroxybenzalacetone (DBL), gallic acid, syringic acid, protocatechuic acid, 3,4-dihydroxybenzaldehyde and 2,5-dihydroxyterephthalic acid. We analyzed their inhibitory effects on DNA polymerase (pol) and DNA topoisomerase (topo), and their effects on human cancer cell growth. All isolated compounds inhibited human topo II activity; the most potent were DBL and CA, which contain a catechol propanoid moiety. CA and DBL inhibited the activity of human topo I, whereas other compounds had no effect. No compound modulated the activities of 11 mammalian pol species or other DNA metabolic enzymes, including T7 RNA polymerase, mouse IMP dehydrogenase (type II), T4 polynucleotide kinase and bovine deoxyribonuclease I. CA and DBL markedly suppressed the proliferation of human colon HCT116 carcinoma cells with an LD50 of 70.0 and 49.4µM, respectively, and halted the cell cycle in the G2/M phase. The suppressive effect of these compounds on cancer cell growth correlated with their ability to inhibit topo II. These results suggest that CA- and DBL-dependent decreases in cell proliferation are due to the inhibition of cellular topo II. The mechanism of action of these catechol propanoid compounds and the implication for their use as anticancer agents are discussed.

Mol Med Rep. 2013 Aug ;8(2):535-42. Epub 2013 Jun 25. PMID: 23799608


Nano-Curcumin is a safe compound with potent ability as an anti-cancer and antimicrobial agent.

Background Curcumin (diferuloylmethane) is a polyphenol derived from the plant Curcuma longa, commonly called turmeric. Extensive research over the last 50 years has demonstrated that these polyphenols play an important role in the maintenance of health and prevention of diseases, in addition to its therapeutic benefits such as anti-tumor, anti-inflammatory, and anti-oxidant activities. Materials and methods This study is devoted to the enhancement of the solubility and bioavailability of curcumin nanoparticles prepared by a process based on a wet-milling technique and then examine in vitro against prostate cancer cell line 3 (PC3), human embryonic kidney cell line (HEK), human erythrocytes (red blood cells (RBCs)), and against fourth different bacterial strains two gram-positive (Micrococcus luteus ATCC 9341, Staphylococcus aureus ATCC 29213), two gram-negative (Escherichia coli ATCC 25922, Pseudomonas aeruginosa ATCC 27853). Results The cell viability curve, the half maximal inhibitory concentration (IC50), and the minimum bactericidal concentration (MBC) were evaluated. Nanocurcumin displayed significant activity against cancer cell line (PC3) and low toxicity against normal cells (HEK) compared with parent curcumin in favor of PC3 (P  0.05). On the other hand, the results demonstrate that, the MBCs of nanocurcumin were lower than curcumin for all different bacterial strains. Moreover, the selected gram-positive bacteria had higher sensitivity than the selected gram-negative bacteria for both curcumin and nanocurcumin. In conclusion, all these findings not only indicate that nanocurcumin safe compound has a potent ability as anti-cancer and antimicrobial activities, but also well justify the avail of using nanocurcumin as prostate cells PC3 anti-cancer, and antimicrobial agent for nanocurcumin are markedly improved by decreasing particle size to the nano-scale regime.

Artif Cells Nanomed Biotechnol. 2016 Jan 8:1-10. Epub 2016 Jan 8. PMID: 26747522


These findings provide new evidence that the anti-metastatic and anti-EMT activities of Curcumin.

Thyroid cancers usually possess a good prognosis while the risks of recurrence and metastasis turn out to be a disturbing issue. Curcumin [bis(4-hydroxy-3-methoxy-phenyl)-1,6-heptadiene-3,5-dione] is a natural polyphenolic compound mainly found in turmeric (Curcuma longa). Our previous studies have demonstrated that curcumin showed proliferation-inhibitory and apoptosis-inducing effects on K1 papillary thyroid cancer cells. However, the mechanism underlying the inhibition effects of curcumin on thyroid cancer cells remains unclear. Herein, we demonstrated that curcumin remarkably increased the expression of the epithelial marker E-cadherin and repressed the expression of the mesenchymal marker vimentin in human papillary thyroid carcinoma BCPAP cells. Curcumin also suppressed multiple metastatic steps of BCPAP cells, including cell attachment, spreading as well as migration. In addition, the transcription, secretion and activation of matrix metalloproteinases (MMPs) induced by transforming growth factor-β1 (TGF-β1) in BCPAP cells were mitigated upon curcumin treatment. Further evidence showed that curcumin decreased TGF-β1-mediated phosphorylation of Smad2 and Smad3. These results revealed that curcumin inhibited the TGF-β1-induced epithelial-mesenchymal transition (EMT) via down-regulation ofSmad2/3 signalling pathways. Our findings provide new evidence that the anti-metastatic and anti-EMT activities of curcumin may contribute to the development of chemo-preventive agents for thyroid cancer treatment.

Exp Cell Res. 2016 Jan 27. Epub 2016 Jan 27. PMID: 26826337


This review summarizes evidence suggesting that silibinin can inhibit pSTAT3 in preclinical cancer models.

Signal transducer and activator of transcription 3 (STAT3) is constitutively activated in many different types of cancer and plays a pivotal role in tumor growth and metastasis. Retrospective studies have established that STAT3 expression or phospho-STAT3 (pSTAT3 or activated STAT3) are poor prognostic markers for breast, colon, prostate and non-small cell lung cancer. Silibinin or silybin is a natural polyphenolic flavonoid which is present in seed extracts of milk thistle (Silybum marianum). Silibinin has been shown to inhibit multiple cancer cell signaling pathways in preclinical models, demonstrating promising anticancer effects in vitro and in vivo. This review summarizes evidence suggesting that silibinin can inhibit pSTAT3 in preclinical cancer models. We also discuss current strategies to overcome the limitations of oral administration of silibinin to cancer patients to translate the bench results to the bed side. Finally, we review the ongoing clinical trials exploring the role of silibinin in cancer.

Cancer Treat Rev. 2015 Jun ;41(6):540-6. Epub 2015 Apr 27. PMID: 25944486


All four theaflavin derivatives tested reduced the viability of ovarian cancer cells.

BACKGROUND: Some polyphenols induce apoptosis and inhibit angiogenesis. Consumption of black tea, rich in polyphenols, has been found to reduce ovarian cancer risk. Theaflavin (TF1), theaflavin-3-gallate (TF2a), theaflavin-3'-gallate (TF2b) and theaflavin-3, 3'-digallate (TF3) are four main theaflavin derivatives found in black tea.MATERIALS AND METHODS: Cell proliferation assay, Hoechst 33342 staining assay, Caspase-Glo Assay, western blot, human umbilical vein endothelial cell tube formation assay and vascular endothelial growth factor (VEGF) enzyme-linked immunosorbent assay were performed.RESULTS: All four theaflavin derivatives reduced viability of ovarian cancer cells at lower concentrations than with normal ovarian cells. TF1 mainly mediated apoptosis via the intrinsic pathway, while the others via the intrinsic and extrinsic pathways. TF1 inhibited tube formation via reducing VEGF secretion in a hypoxia-inducible factor 1α-independent manner, while the others in a HIF1α-dependent way.CONCLUSION: All four theaflavin derivatives inhibited ovarian cancer cells. Some of the effects and mechanisms of TF1 are different from those of the other three theaflavin derivatives.

Anticancer Res. 2016 Feb ;36(2):643-51. PMID: 26851019


Curcumin-treated cancer cells show mitotic disturbances leading to growth arrest and induction of senescence phenotype.

Cellular senescence is recognized as a potent anticancer mechanism that inhibits carcinogenesis. Cancer cells can also undergo senescence upon chemo- or radiotherapy. Curcumin, a natural polyphenol derived from the rhizome of Curcuma longa, shows anticancer properties both in vitro and in vivo. Previously, we have shown that treatment with curcumin leads to senescence of human cancer cells. Now we identified the molecular mechanism underlying this phenomenon. We observed a time-dependent accumulation of mitotic cells upon curcumin treatment. The time-lapse analysis proved that those cells progressed through mitosis for a significantly longer period of time. A fraction of cells managed to divide or undergo mitotic slippage and then enter the next phase of the cell cycle. Cells arrested in mitosis had an improperly formed mitotic spindle and were positive forγH2AX, which shows that they acquired DNA damage during prolonged mitosis. Moreover, the DNA damage response pathway was activated upon curcumin treatment and the components of this pathway remained upregulated while cells were undergoing senescence. Inhibition of the DNA damage response decreasedthe number of senescent cells. Thus, our studies revealed that the induction of cell senescence upon curcumin treatment resulted from aberrant progression through the cell cycle. Moreover, the DNA damage acquired by cancer cells, due to mitotic disturbances, activates an important molecular mechanism that determines the potential anticancer activity of curcumin.

Int J Biochem Cell Biol. 2016 Feb 22 ;74:33-43. Epub 2016 Feb 22. PMID: 26916504


Polyphenol stabilized colloidal gold nanoparticles from Abutilon indicum leaf extract induce apoptosis in HT-29 colon cancer cells.

Green synthesized gold nanoparticles have received substantial attention owing to their biomedical applications, particularly in cancer therapy. Although anticancer activities of green synthesized gold nanoparticles have been reported earlier, the underlying mechanism behind their anticancer activity is still to be understood. The present study, describes the green synthesis of Abutilon indicum gold nanoparticles (AIGNPs) from Abutilon indicum leaf extract (AILE) and their cytotoxic mechanism in colon cancer cells. Dimensions of spherical shaped AIGNPs were found to be in the range of 1-20nm as determined by TEM. GC-MS and FTIR analysis indicated the presence of polyphenolic groups in AILE, which might have been involved in the stabilization of AIGNPs. In vitro free radical scavenging analysis revealed the radical quenching activity of AIGNPs. Further, the AIGNPs exhibited cytotoxicity in HT-29 colon cancer cells with IC50 values of 210 and 180μg/mL after 24 and 48h. This was mediated through nuclear morphological changes and cell membrane damage as evidenced by acridine orange/ethidium bromide, propidium iodide and AnnexinV-Cy3 staining methods. Mechanism of the observed cytotoxicity of AIGNPs was explained on the basis of increased levels of reactive oxygen species and simultaneous reduction in cellular antioxidants, which might have caused mitochondrial membrane potential loss, DNA damage and G1/S phase cell cycle arrest. Expression of cleaved Caspase-9, Caspase-8, Caspase-3, Lamin A/C and PARP, provided the clues for the induction of intrinsic and extrinsic apoptosis pathways in AIGNPs treated HT-29 cells. The study provides a preliminary guidance towards the development of colon cancer therapy using green synthesized gold nanoparticles.

Colloids Surf B Biointerfaces. 2016 Mar 26 ;143:499-510. Epub 2016 Mar 26. PMID: 27038915


This review focuses on curcumin's therapeutic effectiveness in vitro and in vivo in prostate cancer models.

Primary prostate cancer, also known as prostate adenocarcinoma (PCa), is a devastating cancer in men worldwide. Europe and developing countries of Asia have fewer reported cases of prostate cancer compared to increasing cases in the United States with higher incidence in Black men. Risk factors associated with prostate cancer are aging, genetics, lifestyle, high body mass index as well as carcinogenic exposure to carbon-containing fuels, tobacco, and charbroiled meats. Hormone therapy and radical prostatectomy are commonly implemented treatments. The>20.000 prostate cancer deaths of 2013 suggest that there exists a need for enhanced chemopreventive and therapeutic agents for prostate cancer treatment. Fruits, vegetables, and red wines contain high levels of polyphenolic levels. Consumption of these products may provide chemoprevetion of PCa. Curcumin, the major compound from the turmeric rhizome Curcuma longa has long been used for medicinal purposes as an antiseptic and wound healing. This review focuses on curcumin's therapeutic effectiveness in vitro and in vivo in prostate cancer models. The review will highlight the mechanisms of actions of curcumin in the signaling pathways of prostate cancer.

Life Sci. 2016 Mar 23. Epub 2016 Mar 23. PMID: 27018446


Curcumin could be an ideal chemopreventive agent against H. pylori mediated gastric carcinogenesis.

Curcumin, a yellow pigment and principal polyphenolic Curcuminoid obtained from the turmeric rhizome Curcuma longa, is commonly used as a food-coloring agent. Studies suggest that curcumin has a wide range of beneficial properties e.g., anti-inflammatory, anti-oxidant, anti-cancer, anti-proliferative, anti-fungal and anti-microbial. These pleiotropic activities prompted several research groups to elucidate the role of curcumin in Helicobacter pylori (H. pylori) infection. This is the first review with this heading where we discussed regarding the role of curcumin as an anti-H. pylori agent along with its potential in other gastrointestinal diseases. Based on several in vitro, early cell culture, animal research and few pre-clinical trials, curcumin projected as a potential therapeutic candidate against H. pylori mediated gastric pathogenesis. This review sheds light on the anti-H. pylori effects of curcumin in different models with meticulous emphasis on its anti-oxidant, anti-inflammatory and anti-carcinogenic effects as well as some critical signaling and effecter molecules. Remarkably, non-toxic molecule curcumin fulfills the characteristics for an ideal chemopreventive agent against H. pylori mediated gastric carcinogenesis but the foremost challenge is to obtain the optimum therapeutic levels of curcumin, due to its low solubility and poor bioavailability. Further, we have discussed about the possibilities for improving its efficacy and bioavailability. Lastly, we concluded with the anticipation that in near future curcumin may be used to develop a therapeutic drug against H. pylori mediated gastric ailments through improved formulation or delivery systems, facilitating its enhanced absorption and cellular uptake.

World J Gastroenterol. 2016 Mar 7 ;22(9):2736-48. PMID: 26973412


Co-supplementation of melatonin antioxidant ameliorates these toxic effects of gossypol.

PURPOSE OF STUDY: To determine melatonin as a potential natural antioxidant to mitigate the genotoxic effects of promising anti-cancer drug gossypol in human lymphocytes.INTRODUCTION: Gossypol, is a polyphenolic compound naturally occurring in cotton seed, was originally identified as a male contraceptive but it has several proposed clinical applications. Gossypol has anti-proliferative effects on cancer cell lines. However, its genotoxic effects on normal cells are not much studied. Hence, there is a paucity of data available. Hence, the study was conducted to investigate gossypol-induced genotoxic effects on lymphocytes.METHODS: Peripheral blood lymphocyte cultures (PBLC) were done and exposed by two different doses of an anti-cancer drug, gossypol (0.274 mM, 1.645 mM) to check genotoxic effects. Melatonin (0.2 mM) is used as an antioxidant. Genotoxic indices such as sister chromatid exchanges (SCEs), cell cycle proliferative index (CCPI), average generation time (AGT), population doubling time (PDT) were assayed in the cultures.RESULT: Gossypol-treated groups indicated significant increases in frequency of SCEs calculated for SCE/plate and SCE/chromosome. Furthermore, CCPI showed a remarkable reduction and increased AGT and PDT levels were found in exposed cultures. When the higher dose of gossypol cultures was treated along with melatonin, these indices were found to be declined and comparable to control.CONCLUSION: Gossypol, an anti-cancer drug, induces genotoxicity on lymphocyte cells and co-supplementation of melatonin antioxidant ameliorates these toxic effects of gossypol.

Drug Chem Toxicol. 2016 Apr 12:1-5. Epub 2016 Apr 12. PMID: 27071859


This review contributed to clarifying the mechanisms of absorption and metabolism of isoquercitrin.

This review was based on a literature search of PubMed and Scielo databases using the keywords"quercetin, rutin, isoquercitrin, isoquercitin (IQ), quercetin-3-glucoside, bioavailability, flavonols and favonoids, and cancer"and combinations of all the words. We collected relevant scientific publications from 1990 to 2015 about the absorption, bioavailability, chemoprevention activity, and treatment effects as well as the underlying anticancer mechanisms of isoquercitin. Flavonoids are a group of polyphenolic compounds widely distributed throughout the plant kingdom. The subclass of flavonols receives special attention owing to their health benefits. The main components of this class are quercetin, rutin, and IQ, which is a flavonoid and although mostly found as a glycoside, is an aglycone (lacks a glycoside side chain). This compound presents similar therapeutic profiles to quercetin but with superior bioavailability, resulting in increased efficacy compared to the aglycone form. IQ has therapeutic applications owing to its wide range of pharmacological effects including antioxidant, antiproliferative, anti-inflammatory, anti-hypertensive, and anti-diabetic. The protective effects of IQ in cancer may be due to actions on lipid peroxidation. In addition, the antitumor effect of IQ and its underlying mechanism are related to interactions with Wnt signaling pathway, mixed-lineage protein kinase 3, mitogen-activated protein kinase, apoptotic pathways, as well proinflammatory protein signaling. This review contributed to clarifying the mechanisms of absorption, metabolism, and actions of IQ and isoquercitrin in cancer.

World J Clin Oncol. 2016 Apr 10 ;7(2):189-99. PMID: 27081641


Apple and Hop-polyphenols inhibit P. gingivalis-mediated precursor of MMP-9 activation and invasion of oral squamous cell carcinoma cells.

BACKGROUND: Recent epidemiological studies have revealed a significant association between periodontitis and oral squamous cell carcinoma (OSCC). Furthermore, periodontitis is markedly associated with orodigestive cancer mortality, while Porphyromonas gingivalis infection has been identified as a specific and potentially independent microbial factor related to increased risk of orodigestive cancer death. We previously reported that P. gingivalis induced the precursor form of matrix metalloproteinase 9 (proMMP9) production via proteinase activated receptor (PAR)-related pathways, after which proMMP9 was activated by gingipains to enhance cellular invasion of SAS cells. In the present study, we examined the effects of selected polyphenols as inhibitors of cellular invasion caused by P. gingivalis gingipains in SAS cells.METHODS: OSCC cells were infected with P. gingivalis strains including gingipain mutants. To evaluate the effects of inhibitors, apple polyphenol (AP), hop bract polyphenol (HBP), high and low molecular weight fractions of HBP (HMW-HBP and LMW-HBP), epigallocatechin gallate (EGCg), KYT-1 (Arg-gingipain inhibitor), and KYT-36 (Lys-gingipain inhibitor) were used. Proteinase activated receptor 2 (PAR2) and PAR4 mRNA expressions were examined using real-time reverse transcription polymerase chain reaction, and signaling pathways were evaluated by western blotting analysis.RESULTS: KYT-1/KYT-36, AP, HBP, and HMW-HBP significantly inhibited PAR2 and PAR4 mRNA expressions, proMMP9 activation, and cellular invasion. Furthermore, AP, HBP, and HMW-HBP reduced activation of HSP27 and Ets1 and nuclear translocation of NF-kB, whereas EGCg and LMW-HBP did not.CONCLUSION: These results suggest that AP, HBP, and HMW-HBP are potent inhibitors of proMMP9 activation and cellular invasion mediated with P. gingivalis in OSCC cells.

J Periodontol. 2016 May 13:1-21. Epub 2016 May 13. PMID: 27177287


EGCG has the potential for therapeutic effect on oral cancer and may be useful for long-term oral cancer prevention in the future.

Epigallocatechin gallate (EGCG) is a green tea polyphenol that presents anticancer activities in multiple cancer cells, but no available report was addressed for the underling molecular mechanism of cytotoxic impacts on drug-resistant oral squamous cell carcinoma cells. In the present study, the inhibitory effects of EGCG were experienced on cisplatin-resistant oral cancer CAR cells. EGCG inhibited cell viability in a time- and concentration-dependent manner by a sulforhodamine B (SRB) assay. EGCG induced CAR cell apoptosis and autophagy by 4',6-diamidino-2-phenylindole (DAPI) dye, acridine orange (AO) staining and green fluorescent protein (GFP)-tagged LC3B assay, respectively. EGCG also significantly enhanced caspase-9 and caspase-3 activities by caspase activity assay. EGCG markedly increased the protein levels of Bax, cleaved caspase-9, cleaved caspase-3, Atg5, Atg7, Atg12, Beclin-1, and LC3B-II, as well as significantly decreased the expression of Bcl-2, phosphorylated AKT (Ser473) and phosphorylation of STAT3 on Tyr705 by western blotting in CAR cells. Importantly, the protein and gene expression of multidrug resistance 1 (MDR1) were dose-dependently inhibited by EGCG. Overall, downregulation of MDR1 levels and alterations of AKT/STAT3 signaling contributed to EGCG-induced apoptosis and autophagy in CAR cells. Based on these results, EGCG has the potential for therapeutic effect on oral cancer and may be useful for long-term oral cancer prevention in the future.© 2016 Wiley Periodicals, Inc. Environ Toxicol, 2016.

Environ Toxicol. 2016 May 20. Epub 2016 May 20. PMID: 27200496


EGCG has the potential for therapeutic effect on oral cancer and may be useful for long-term oral cancer prevention in the future.

Epigallocatechin gallate (EGCG) is a green tea polyphenol that presents anticancer activities in multiple cancer cells, but no available report was addressed for the underling molecular mechanism of cytotoxic impacts on drug-resistant oral squamous cell carcinoma cells. In the present study, the inhibitory effects of EGCG were experienced on cisplatin-resistant oral cancer CAR cells. EGCG inhibited cell viability in a time- and concentration-dependent manner by a sulforhodamine B (SRB) assay. EGCG induced CAR cell apoptosis and autophagy by 4',6-diamidino-2-phenylindole (DAPI) dye, acridine orange (AO) staining and green fluorescent protein (GFP)-tagged LC3B assay, respectively. EGCG also significantly enhanced caspase-9 and caspase-3 activities by caspase activity assay. EGCG markedly increased the protein levels of Bax, cleaved caspase-9, cleaved caspase-3, Atg5, Atg7, Atg12, Beclin-1, and LC3B-II, as well as significantly decreased the expression of Bcl-2, phosphorylated AKT (Ser473) and phosphorylation of STAT3 on Tyr705 by western blotting in CAR cells. Importantly, the protein and gene expression of multidrug resistance 1 (MDR1) were dose-dependently inhibited by EGCG. Overall, downregulation of MDR1 levels and alterations of AKT/STAT3 signaling contributed to EGCG-induced apoptosis and autophagy in CAR cells. Based on these results, EGCG has the potential for therapeutic effect on oral cancer and may be useful for long-term oral cancer prevention in the future.© 2016 Wiley Periodicals, Inc. Environ Toxicol, 2016.

Environ Toxicol. 2016 May 20. Epub 2016 May 20. PMID: 27200496


Some flavonoids have the potential to be an effective alternative to chemotherapeutic drugs in the treatment of colon cancer.

Colorectal cancer (CRC) is the third most common type of cancer in the world, causing thousands of deaths annually. Although chemotherapy is known to be an effective treatment to combat colon cancer, it produces severe side effects. Natural products, on the other hand, appear to generate fewer side effects than do chemotherapeutic drugs. Flavonoids are polyphenolic compounds found in various fruits and vegetables known to possess antioxidant activities, and the literature shows that several of these flavonoids have anti-CRC propertiesFlavonoids are classified into five main subclasses: flavonols, flavanones, flavones, flavan-3-ols, and flavanonols. Of these subclasses, the flavanonols have a minimum effect against CRC, whereas the flavones play an important role. The main targets for the inhibitory effect of flavonoids on CRC signaling pathways are caspase; nuclear factor kappa B; mitogen-activated protein kinase/p38; matrix metalloproteinase (MMP)-2, MMP-7, and MMP-9; p53;β-catenin; cyclin-dependent kinase (CDK)2 and CDK4; and cyclins A, B, D, and E. In this review article, we summarize the in vitro and in vivo studies that have been performed since 2000 on the anti-CRC properties of flavonoids. We also describe the signaling pathways affected by flavonoids that have been found to be involved in CRC. Some flavonoids have the potential to be an effective alternative to chemotherapeutic drugs in the treatment of colon cancer; well-controlled clinical studies should, however, be conducted to support this proposal.

Int J Med Sci. 2016 ;13(5):374-85. Epub 2016 Apr 29. PMID: 27226778


Curcumin was found to modulate the expression of several pathogenic miRs in brain, ocular, renal, and liver diseases.

Curcumin is a bioactive polyphenol occurring in the rhizomes of Curcuma longa. It is well-reputed for its chemopreventive and anticancer properties; however, recent evidence has revealed numerous biological and pharmacological effects of curcumin that are relevant to the treatment of non-cancer diseases. Mechanistically, curcumin exerts its pharmacological effects through anti-inflammatory and antioxidant mechanisms via interaction with different signaling molecules and transcription factors. In addition, epigenetic modulators such as microRNAs (miRs) have emerged as novel targets of curcumin. Curcumin was found to modulate the expression of several pathogenic miRs in brain, ocular, renal, and liver diseases. The present systematic review was conducted to identify miRs that are regulated by curcumin in non-cancer diseases.

Mol Diagn Ther. 2016 May 30. Epub 2016 May 30. PMID: 27241179


Mangiferin has multipotent anti-inflammatory potentials.

Over the last era, small molecules sourced from different plants have gained attention for their varied and long-term medicinal benefits. Their advantageous therapeutic effects in diverse pathological complications lead researchers to give an ever-increasing emphasis on them and discover their novel therapeutic potentials. Among these, the heat stable, xanthonoid group of organic molecules has gained special importance with distinctive regards to the bioactive molecule mangiferin due to its solubility in water. Mangiferin, a yellow polyphenol having C-glycosyl xanthone structure, is widely present in different edible sources like mango, and possesses numerous biological activities. Extensive research with this molecule shows its antioxidant, anti-inflammatory, antidiabetic, anticancer, antimicrobial, analgesic, and immunomodulatory properties. Thus, it provides protection against a wide range of physiological disorders. The C-glucosyl linkage and polyhydroxy groups in mangiferin's structure contribute essentially to its free radical-scavenging activity. Moreover, its ability in regulating various transcription factors like NF-κB, Nrf-2, etc. and modulating the expression of different proinflammatory signaling intermediates like tumor necrosis factor-α, COX-2, etc. contribute to its anti-inflammatory, anticancer, and antidiabetic potentials. In this comprehensive article, information has been provided about the sources,chemical structure, metabolism, and different biological activities of mangiferin with special emphasis on the underlying cellular signal transduction pathways. Insights into an in-depth assessment of mangiferin's anti-inflammatory therapeutic potential have also been discussed in detail. On an overall perspective, this review aims to stage mangiferin's diversified therapeutic applications and its emerging possibility as a promising drug in future based on its anti-inflammatory property. © 2016 BioFactors, 2016.

Biofactors. 2016 May 24. Epub 2016 May 24. PMID: 27219011


Curcumin and Ellagic acid show anti-HPV activity as evidenced by decrease in the HPV E6 oncoprotein on HeLa cells.

Cervical cancer and precancerous lesions of the cervix continue to be a global health issue, and the medication for the treatment for chronic HPV infection so far has not been effective. Potential anticancer and anti HPV activities of two known phytochemicals, Curcumin and Ellagic acid were evaluated in HeLa cervical cancer cells. Curcumin is a natural compound found in the root of Curcuma longa plant and Ellagic acid a polyphenol found in fruits of strawberries, raspberries and walnuts. The combination of Curcumin and Ellagic acid at various concentrations showed better anticancer properties than either of the drug when used alone as evidenced by MTT assay. Besides this, Curcumin and Ellagic acid also restore p53, induce ROS formation and DNA damage. Mechanistic study further indicated that Curcumin and Ellagic acid show anti-HPV activity as evidenced by decrease in the HPV E6 oncoprotein on HeLa cells.

Biomed Pharmacother. 2016 Jul ;81:31-7. Epub 2016 Apr 8. PMID: 27261574


The anti-cancer effect of green tea can be explained by either its anti-oxidative or pro-oxidative property.

Tea derived from the leaves and buds of Camellia sinensis (Theaceae) is consumed worldwide. Green tea contains various components with specific health-promoting effects, and is believed to exert protective effects against diseases including cancer, diabetes and hepatitis, as well as obesity. Of the various tea components, the polyphenol catechins have been the subject of extensive investigation and among the catechins, (-)-epigallocatechin gallate has the strongest bioactivity in most cases. Our research group has postulated that hepatocyte nuclear factor-4α, sterol regulatory element-binding proteins, and tumor necrosis factor-α are targets of green tea constituents including (-)-epigallocatechin gallate for their anti-diabetes, anti-obesity, and anti-hepatitis effects, respectively. Published papers were reviewed to determine whether the observedchanges in these factors can be correlated with anti-cancer effects of green tea. Two major action mechanisms of (-)-epigallocatechin gallate have been proposed; one associated with its anti-oxidative properties and the other with its pro-oxidative activity. When reactive oxygen species are assumedto be involved, our findings that (-)-epigallocatechin gallate down- regulated hepatocyte nuclear factor-4α, sterol regulatory element-binding proteins, and tumor necrosis factor-α may explain the anti-cancer effect of green tea as well. However, further studies are required to elucidate which determinant directs (-)-epigallocatechin gallate action as an anti-oxidant or a pro-oxidant for favorable activity.

Asian Pac J Cancer Prev. 2016 ;17(4):1649-54. PMID: 27221834


EGCG may be useful for prevention of intestinal disorders or bacterial infection in animals/humans.

SCOPE: Green tea has been known to confer numerous health benefits such as the prevention of cardiovascular disease, cancers, and obesity. Epigallocatechin-3-gallate (EGCG) is the major polyphenol present in green tea. Since EGCG is a food-derived component, intestinal epithelial cells lining the gastrointestinal tract are constantly and directly exposed to EGCG. It is anticipated that EGCG can exert beneficial effects in the intestine. The aim of this study was to explore the protective effects of EGCG on intestinal barrier functions against bacterial translocation by using a porcine jejunal epithelial cell line, IPEC-J2.METHODS AND RESULTS: EGCG reduced bacterial translocation across IPEC-J2 cell monolayers through the enhancement of the intestinal epithelial immunological barrier function by inducing secretion of antimicrobial peptides, porcineβ-defensins 1 and 2 (pBD-1 and 2), which possessed higher antimicrobial activity against Escherichia coli. Further mechanistic studies demonstrated that EGCG upregulated pBD-2 but not pBD-1 via the p38 mitogen-activated protein kinase dependent pathway. Such effects were not an"artifact"of hydrogen peroxide, catechin dimers, or other auto-oxidation products generated from EGCG in cell culture media.CONCLUSION: Our results imply that EGCG may be useful for prevention of intestinal disorders or bacterial infection in animals/humans.

Mol Nutr Food Res. 2016 May ;60(5):1048-58. Epub 2016 Apr 4. PMID: 26991948


This reviews natural plants as breast cancer preventatives or use in treatments.

For centuries, herbs and plants have been used for medicinal purposes and as food as well. This review concerns about different types of plants that retain the immune stimulating and anti-tumor properties. Large variety of active phytochemicals such as carotenoids, flavonoids, ligands, polyphenolics, terpenoids, sulfides, lignans and plant sterols has been identified in different types of herbs. These phytochemicals have different mechanisms of action. They either stimulate the protective enzyme like glutathione transferase or prevent the cell proliferation. This review has centered on the biochemical properties of Allium sativum, Echinacea, Curcuma longa, Arctium lappa, Camellia sinensis, Panax ginseng and Flax seed. Extracts and juices of Withania somnifera, Amoora rohituka, Dysoxylum binectariferum and Vaccinium macrocarpon, respectively also used as anti-breast cancer. The volatile oils and extracts of these herbs and plants inhibit the synthesis of mevalonate that lessen the tumor growth and cholesterol synthesis.

Saudi Pharm J. 2016 May ;24(3):233-40. Epub 2016 May 5. PMID: 27275107


EGCG in combination with cisplatin can be used for the management of head and neck squamous carcinoma cancer stem cells.

Most solid cancers including head and neck squamous carcinoma (HNSC) are believed to be initiated from and maintained by cancer stem cells (CSCs) that are responsible for treatment resistance, resulting in tumour relapse. Epigallocatechin-3-gallate (EGCG), the most abundant polyphenol in green tea, can potently inhibit cancer growth and induce apoptosis in various cancers, including HNSC. However, its effect on HNSC CSCs is not well elucidated. In this study, we examined the anti-tumour effect of EGCG on HNSC CSCs. We demonstrated that EGCG inhibits the self-renewal capacity of HNSC CSCs by suppressing their sphere forming capacity, and attenuates the expression of stem cell markers, such as Oct4, Sox2, Nanog and CD44. EGCG treatment augmented cisplatin-mediated chemosensitivity by suppressing ABCC2 and ABCG2 transporter genes, which are putative molecules of treatment resistance of CSC. In addition, the combination treatment of EGCG and cisplatin inhibited tumour formation and induced apoptosis in a xenograft model. As one of mechanisms of suppression of HNSC CSC traits, EGCG decreased the transcriptional level of Notch, resulting in the inhibition of Notch signalling. Collectively, our data suggest that EGCG in combination with cisplatin can be used for the management of HNSC CSCs.

Eur J Cancer. 2013 Oct ;49(15):3210-8. Epub 2013 Jul 19. PMID: 23876835


Berry anthocyanins reduce proliferation of human colorectal carcinoma cells.

Colorectal cancer is the fourth most common type of cancer worldwide, and adenocarcinoma cells that form the majority of colorectal tumors are markedly resistant to antineoplastic agents. Epidemiological studies have demonstrated that consumption of fruits and vegetables that are rich in polyphenols, is linked to reduced risk of colorectal cancer. In the present study, the effect of a standardized anthocyanin (ACN)‑rich extract on proliferation, apoptosis and cell cycle in the Caco-2 human colorectal cancer cell line was evaluated by trypan blue and clonogenic assays and western blot analysis of cleaved caspase‑3 and p21Waf/Cif1. The results of the current study demonstrated that the ACN extract markedlydecreased Caco‑2 cell proliferation, induced apoptosis by activating caspase‑3 cleavage, and upregulated cyclin‑dependent kinase inhibitor 1 (p21Waf/Cif1) expression in a dose dependent manner. Furthermore, ACN extract was able to produce a dose‑dependent increase of intracellular reactiveoxygen species (ROS) in Caco‑2 cells, together with a light increase of the cell total antioxidant status. In conclusion, the present study demonstrated that a standardized berry anthocyanin rich extract inhibited proliferation of Caco‑2 cells by promoting ROS accumulation, inducing caspase‑3activation, and upregulating the expression of p21Waf/Cif1.

Mol Med Rep. 2016 Jun 13. Epub 2016 Jun 13. PMID: 27314273


EGCG has an anticancer effect on Osteosarcoma cells.

(-)-Epigallocatechin-3-gallate (EGCG), the most abundant and active polyphenol in green tea, has been demonstrated to have anticancer effects in a wide variety of human cancer. MicroRNAs (miRNAs) are a class of short noncoding RNAs and play important role in gene regulation and are critically involved in the pathogenesis and progression of human cancer. This study aims to investigate the effects of EGCG on osteosarcoma (OS) cells and elucidate the underlying mechanism. Cellular function assays revealed that EGCG inhibited cell proliferation, induced cell cycle arrest and promoted apoptosis of OS cells in vitro, and also inhibited the growth of transplanted tumors in vivo. By miRNA microarray and RT-qPCR analysis, miR-1 was found to be significantly upregulated in MG-63 and U-2OS treated by EGCG in dose- and time-dependent manners, and miR-1 downregulation by inhibitor mimics attenuated EGCG-induced inhibition on cell growth of OS cells. We also confirmed that miR-1 was also frequently decreased in clinical OS tumor tissues. Moreover, both EGCG and miR-1 mimic inhibited c-MET expression, and combination treatment with EGCG and c-MET inhibitor (crizotinib) had enhanced inhibitory effects on the growth of MG-63 and U-2OS cells. Taken together, these results suggest that EGCG has an anticancer effect on OS cells, at least partially, through regulating miR-1/c-MET interaction.

Tumour Biol. 2016 Apr ;37(4):4373-82. Epub 2015 Oct 24. PMID: 26499783


EGCG may accentuate oxidative stress to inhibit growth of ovarian cancer cells and sensitize them to cisplatin.

The green tea polyphenol epigallocatechin-3-gallate (EGCG) has cancer chemopreventive properties against various types of cancers. The compound is known to attack various targets in transformed cells. In this report, we examined the action of EGCG on ovarian cancer cells. Eight ovarian cancer cell lines were tested (SKOV3, CAOV3, OVCAR3, OVCAR10, A2780, CP70, C30, and C200) and showed IC50s for EGCG at the micromolar range, including ones that are resistant to the chemotherapeutic drug cisplatin. The ovarian cancer cells were sensitive to H2O2 at similar concentrations, and EGCG treatment led to enhanced intracellular H2O2. Neutralization with pyruvate, a scavenger of H2O2, suggests that the toxicity of EGCG may be mediated by oxidative stress from the free radical. Addition of Tempol, a superoxide dismutase mimetic, demonstrates that H2O2 might be generated endogenously from superoxide. The toxicity of cisplatin and the development of cisplatin resistance are major obstacles in treatment of ovarian cancer. We found that addition of EGCG amplified the toxicity of cisplatin. EGCG increased cisplatin potency by three to six-fold in SKOV3, CAOV3, and C200 cells, the latter being a cell line induced to have several hundred fold resistant to cisplatin above the parental line. Our findings suggest that EGCG may accentuate oxidative stress to inhibit growth of ovarian cancer cells and sensitize them to cisplatin.

J Cell Physiol. 2006 May ;207(2):389-96. PMID: 16402374


The use of polyphenols might represent a promising strategy to contrast the development or to prevent malignant mesothelioma.

Malignant Mesothelioma (MM) is a tumor of the serous membranes linked to exposure to asbestos. A chronic inflammatory response orchestrated by mesothelial cells contributes to the development and progression of MM. The evidence that: (a) multiple signaling pathways are aberrantly activated in MM cells; (b) asbestos mediated-chronic inflammation has a key role in MM carcinogenesis; (c) the deregulation of the immune system might favor the development of MM; and (d) a drug might have a better efficacy when injected into a serous cavity thus bypassing biotransformation and reaching an effective dose has prompted investigations to evaluate the effects of polyphenols for the therapy and prevention of MM. Dietary polyphenols are able to inhibit cancer cell growth by targeting multiple signaling pathways, reducing inflammation, and modulating immune response. The ability of polyphenols to modulate the production of pro-inflammatory molecules by targeting signaling pathways or ROS might represent a key mechanism to prevent and/or to contrast the development of MM. In this review, we will report the current knowledge on the ability of polyphenols to modulate the immune system and production of mediators of inflammation, thus revealing an important tool in preventing and/or counteracting the growth of MM.

Nutrients. 2016 ;8(5). Epub 2016 May 9. PMID: 27171110


Cyanidin-3-O-glucoside chloride exhibits cytotoxicity on Caco-2 cells in vitro and induces apoptosis in Caco-2 cells.

Three polyphenols were isolated and purified from sugar beet molasses by ultrasonic-aid extraction and various chromatographic techniques, and their structures were elucidated by spectral analysis. Cytotoxicity and the molecular mechanism were measured by methyl thiazolyl tetrazolium (MTT) assay, flow cytometry, caspase-3 activity assay and Western blot assay. The results showed that gallic acid, cyanidin-3-O-glucoside chloride and epicatechin have cytotoxicity to the human colon, hepatocellular and breast cancer cells. Cyanidin-3-O-glucoside chloride showed its cytotoxicity against various tumor cell lines, particularly against colon cancer Caco-2 cells with half maximal inhibitory concentration (IC50) value of 23.21± 0.14 μg/mL in vitro. Cyanidin-3-O-glucoside chloride may be a potential candidate for the treatment of colon cancer. In the mechanism study, cyanidin-3-O-glucoside chloride increased the ratio of cell cycle at G₀/G₁ phase and reduced cyclin D1 expression on Caco-2 cells. Cyanidin-3-O-glucoside chloride decreased mutant p21 expression, and increased the ratio of Bax/Bcl-2 and the activation of caspase-3 to induce apoptosis.

Int J Mol Sci. 2016 ;17(7). Epub 2016 Jun 23. PMID: 27347927


This review focuses on the different targets of curcumin to treat cancer.

Curcumin, is a polyphenol from Curcuma longa (turmeric plant), is a polyphenol that belongs to the ginger family which has long been used in Ayurveda medicines to treat various diseases such as asthma, anorexia, coughing, hepatic diseases, diabetes, heart diseases, wound healing and Alzheimer's. Various studies have shown that curcumin has anti-infectious, anti-inflammatory, anti-oxidant, hepatoprotective, thrombosuppressive, cardio protective, anti-arthritic, chemo preventive and anti-carcinogenic activities. It may suppress both initiation and progression stages of cancer. Anticancer activity of curcumin is due to negative regulation of inflammatory cytokines, transcription factors, protein kinases, reactive oxygen species (ROS) and oncogenes. This review focuses on the different targets of curcumin to treat cancer.

Asian Pac J Cancer Prev. 2016 ;17(6):2735-9. PMID: 27356682


Honokiol targets mitochondria to halt cancer progression and metastasis.

Cancer continues to be the leading cause of death worldwide. Plants have a long history of use in the treatment of cancer. Honokiol (HNK) is an important bioactive compound found in the bark of Magnolia tree, and has been shown to inhibit cancer growth and metastasis in many cell types in vitro and in animal models. Resistance to chemotherapy and radiotherapy is the major obstacle for cure of cancer. Combination of HNK with many traditional chemotherapeutic drugs as well as radiation sensitizes cancer cells to apoptotic death, suggesting that HNK not only directly inhibits primary cancers and metastasis, but also has potential to overcome drug resistance. Ultimately, this may mean that HNK could be combined with traditional chemotherapies administered at lower doses to significantly reduce toxicity, meanwhile enhance efficacy. As a natural compound, HNK is composed of polyphenols and has been described in many studies targeting multiple key cell signaling molecules. Mitochondria are the main hub for cellular energy production and play an important role in cell survival, and are the key target identified for HNK to mediate cancer cell death, survival, and metastasis. In this review, we have summarized different aspects of HNK's anti-cancer effects from recent accumulated literature, as well as the underlying molecular mechanisms. This review is primarily focused on the effects of HNK on epidermal growth factor receptor (EGFR) and signal transduction and activator of transcription 3 (STAT3) signaling, as well as the broader regulation of mitochondrial function and cancer cell metabolism.

Mol Nutr Food Res. 2016 Jun ;60(6):1383-95. Epub 2016 May 6. PMID: 27276215


Magnolol and polyphenol mixture remarkably induced cell apoptosis by arresting the cell cycle in the G0/G1 phase.

Histone modifications play critical roles in the progression of non-small cell lung cancer (NSCLC), which accounts for almost 85% of all diagnosed lung cancers. Magnolol and polyphenol mixture (PM) derived from Magnolia officinalis exhibited remarkable antitumor activities in lung cancer. However, the epigenetic effects and molecular mechanisms of magnolol and PM in NSCLC have yet to be reported. In this study, the epigenetic effects of magnolol and PM in NSCLC were examined in vitro and in vivo. Results revealed that magnolol and PM significantly suppressed the expression levels and function of class I histone deacetylases (HDACs). In A549 and H1299 cells, magnolol and PM remarkably induced cell apoptosis by arresting the cell cycle in the G0/G1 phase while simultaneously activating various pro-apoptotic signals, including TRAIL-R2 (DR5), Bax, caspase 3, cleaved caspase 3, and cleaved PARP. However, these apoptosis-promoting effects could be attenuated by TSA, which is a specific class I HDACs inhibitor. ChIP assays also demonstrated that magnolol and PM significantly enriched the histone acetyl mark (H3K27ac) in the promoter region of DR5. In A549 xenograft model, magnolol and PM notably reduced tumor growth by 44.40% and 35.40%, respectively. Therefore, magnolol and PM, as potential inhibitors of class I HDACs, induced tumor cell apoptosis and suppressed tumor growth partially by epigenetically activating DR5, which is a key protein in death receptor signaling pathway.

Pharmacol Res. 2016 Jun 3 ;111:113-125. Epub 2016 Jun 3. PMID: 27268146


These results suggest that curcumin induced the apoptosis of Y79 cells through the activation of JNK and p38 MAPK pathways.

Curcumin, a naturally occurring polyphenolic compound present in turmeric (Curcuma longa), exerts antitumor effects in various types of malignancy. However, the precise mechanisms responsible for the effects of curcumin on retinoblastoma (RB) cells have not been fully explored. In the present study, the molecular mechanisms by which curcumin exerts its anticancer effects in RB Y79 cells were investigated. The results showed that curcumin reduced cell viability in Y79 cells. Curcumin induced G1 phase arrest through downregulating the expression of cyclin D3 and cyclin-dependent kinase (CDK)2/6 and upregulating the expression of CDK inhibitor proteins p21 and p27. Curcumin-induced apoptosis of Y79 cells occurred through the activation of caspases-9/-3. Moreover, flow cytometric analysis showed that curcumin induced mitochondrial membrane potential (∆Ψm) collapse in Y79 cells. We also found that curcumin induced the phosphorylation of c-Jun N-terminal kinase (JNK) and p38 mitogen-activated protein kinase (MAPK). JNK and p38 MAPK inhibitors significantly suppressed curcumin‑induced activation of caspases-9/-3 and inhibited the apoptosis of Y79 cells. Taken together, our results suggest that curcumin induced the apoptosis of Y79 cells through the activation of JNK and p38 MAPK pathways. These findings provide a novel treatment strategy for human RB.

Int J Mol Med. 2016 Jul 13. Epub 2016 Jul 13. PMID: 27432244


Rosehip extracts are a powerful antioxidant that produces an antiproliferative effect in Caco-2 cells.

The in vitro antiproliferative and antioxidant effects of different fractions of Rosa canina hips on human colon cancer cell lines (Caco-2) was studied. The compounds tested were total extract (fraction 1), vitamin C (fraction 2), neutral polyphenols (fraction 3) and acidic polyphenols (fraction 4). All the extracts showed high cytotoxicity after 72 h, both low and high concentrations. The flow cytometric analysis revealed that all the fractions produce disturbances in the cell cycle resulting in a concomitant cell death by an apoptotic pathway. Changes in the redox status of Caco-2 cells in response to Rosa canina hips were determined. Cells were exposed to hydrogen peroxide in presence of plant fractions and the production of Reactive Oxygen Species (ROS) was significantly decreased. Therefore, our data demonstrate that rosehip extracts are a powerful antioxidant that produces an antiproliferative effect in Caco-2 cells. Therefore, these results predict a promising future for Rosa canina as a therapeutic agent. Thus, this natural plant could be an effective component of functional foods addressed towards colorectal carcinoma.

PLoS One. 2016 ;11(7):e0159136. Epub 2016 Jul 28. PMID: 27467555


Cocoa catechins and procyanidins are cytotoxic to epithelial ovarian cancer cells.

Over the last four centuries, cocoa and chocolate have been described as having potential medicinal value. As of today, Theobroma cacao L. (Sterculiaceae) and its products are consumed worldwide. They are of great research interest because of the concentration dependent antioxidant as well as pro-oxidant properties of some of their polyphenolic constituents, specially procyanidins and flavan-3-ols such as catechin. This study was aimed at investigating the cellular and molecular changes associated with cytotoxicity, caused due pro-oxidant activity of cocoa catechins and procyanidins, in ovarian cancer cell lines. Extract of non-alkalized cocoa powder enriched with catechins and procyanidins was used to treat human epithelial ovarian cancer cell lines OAW42 and OVCAR3 at various concentrations≤1000μg/mL. The effect of treatment on intracellular reactive oxygen species (ROS) levels was determined. Apoptotic cell death, post treatment, was evaluated microscopically and using flow cytometry by means of annexin-propidium iodide (PI) dual staining. Levels of active caspase-3 as a pro-apoptotic marker and matrix metalloproteinase 2 (MMP2) as an invasive potential marker were detected using Western blotting and gelatin zymography. Treatment with extract caused an increase in intracellular ROS levels in OAW42 and OVCAR3 cell lines. Bright field and fluorescence microscopy of treated cells revealed apoptotic morphology and DNA damage. Increase in annexin positive cell population and dose dependent upregulation of caspase-3 confirmed apoptotic cell death. pro-MMP2 was found to be downregulated in a dose dependent manner in cells treated with the extract. Treated cells also showed areduction in MMP2 activity. Our data suggests that cocoa catechins and procyanidins are cytotoxic to epithelial ovarian cancer, inducing apoptotic morphological changes, DNA damage and caspase-3 mediated cell death. Downregulation of pro-MMP2 and reduction in active MMP2 levels imply a decrease in invasive potential of the cells. Apoptosis and MMP2 downregulation appear to be linked to the increase in intracellular ROS levels, caused due to the prooxidant effect of cocoa procyanidin extract.

Biomed Pharmacother. 2016 Jun 24 ;83:130-140. Epub 2016 Jun 24. PMID: 27470560


Curcumin as a MicroRNA Regulator in Cancer: A Review.

Curcumin is a natural dietary polyphenol for which anti-tumor effects have been documented. Anti-inflammatory and antioxidant properties of curcumin, along with its immunomodulatory, proapoptotic, and antiangiogenic properties, are often referred to as the main mechanisms underlying the anti-tumor effects. At the molecular level, inhibition of NF-kB, Akt/PI3K, and MAPK pathways and enhancement of p53 are among the most important anticancer alterations induced by curcumin. Recent evidence has suggested that epigenetic alterations are also involved in the anti-tumor properties of curcumin. Among these curcumin-induced epigenetic alterations is modulation of the expression of several oncogenic and tumor suppressor microRNAs (miRNAs). Suppression of oncomiRs such as miR-21, miR-17-5p, miR-20a, and miR-27a and over-expression of miR-34 a/c and epithelial-mesenchymal transition-suppressor miRNAs are among the most important effects of curcumin on miRNA homeostasis. The present review will summarize the findings of in vitro and experimental studies on the impact of curcumin and its analogues on the expression of miRNAs involved in different stages of tumor initiation, growth, metastasis, and chemo-resistance.

Rev Physiol Biochem Pharmacol. 2016 Jul 23. Epub 2016 Jul 23. PMID: 27457236


There is strong evidence from cell models which demonstrates that olive polyphenols may inhibit the progression and development of cancer.

The traditional Mediterranean diet (MD) is associated with long life and lower prevalence of cardiovascular disease and cancers. The main components of this diet include high intake of fruit, vegetables, red wine, extra virgin olive oil (EVOO) and fish, low intake of dairy and red meat. Olive oil has gained support as a key effector of health benefits and there is evidence that this relates to the polyphenol content. Olive leaf extract (OLE) contains a higher quantity and variety of polyphenols than those found in EVOO. There are also important structural differences between polyphenols from olive leaf and those from olive fruit that may improve the capacity of OLE to enhance health outcomes. Olive polyphenols have been claimed to play an important protective role in cancer and other inflammation-related diseases. Both inflammatory and cancer cell models have shown that olive leaf polyphenols are anti-inflammatory and protect against DNA damage initiated by free radicals. The various bioactive properties of olive leaf polyphenols are a plausible explanation for the inhibition of progression and development of cancers. The pathways and signaling cascades manipulated include the NF-κB inflammatory response and the oxidative stress response, but the effects of these bioactive components may also result from their action as a phytoestrogen. Due to the similar structure of the olive polyphenols to oestrogens, these have been hypothesized to interact with oestrogen receptors, thereby reducing the prevalence and progression of hormone related cancers. Evidence for the protective effect of olive polyphenols for cancer in humans remains anecdotal and clinical trials are required to substantiate these claims idea. This review aims to amalgamate the current literature regardingbioavailability and mechanisms involved in the potential anti-cancer action of olive leaf polyphenols.

Nutrients. 2016;8(8). Epub 2016 Aug 19. PMID: 27548217


Salvianolic Acid A is a novel anti-cancer candidate through targeting ETAR.

Endothelin-1 (ET-1) autocrine and paracrine signaling modulate cell proliferation of tumor cells by activating its receptors, endothelin A receptor (ETAR) and endothelin B receptor (ETBR). Dysregulation of ETAR activation promotes tumor development and progression. The potential of ETAR antagonists and the dual-ETAR and ETBR antagonists as therapeutic approaches are under preclinical and clinical studies. Salvianolic acid A (Sal A) is a hydrophilic polyphenolic derivative isolated from Salvia miltiorrhiza Bunge (Danshen), which has been reported as an anti-cancer and cardio-protective herbal medicine. In this study, we demonstrate that Sal A inhibits ETAR activation induced by ET-1 in both recombinant and endogenous ETAR expression cell lines. The IC50 values were determined as 5.7µM in the HEK293/ETAR cell line and 3.14 µM in HeLa cells, respectively. Furthermore, our results showed that Sal A suppressed cell proliferation and extended the doubling times of multiple cancer cells, including HeLa, DU145, H1975, and A549 cell lines. In addition, Sal A inhibited proliferationof DU145 cell lines stimulated by exogenous ET-1 treatment. Moreover, the cytotoxicity and cardio-toxicity of Sal A were assessed in human umbilical vein endothelial cells (HUVEC) and Human-induced pluripotent stem cell-derived cardiomyocytes (hiPS-CMs), which proved that Sal A demonstrates no cytotoxicity or cardiotoxicity. Collectively, our findings indicate that Sal A is a novel anti-cancer candidate through targeting ETAR.

Int J Mol Sci. 2016 ;17(8). Epub 2016 Aug 2. PMID: 27490540


Polyphenols have been shown to be effective against multiple targets in cancer development and progression.

Polyphenols, found abundantly in plants, display many anticarcinogenic properties including their inhibitory effects on cancer cell proliferation, tumor growth, angiogenesis, metastasis, and inflammation as well as inducing apoptosis. In addition, they can modulate immune system response and protect normal cells against free radicals damage. Most investigations on anticancer mechanisms of polyphenols were conducted with individual compounds. However, several studies, including ours, have indicated that anti-cancer efficacy and scope of action can be further enhanced by combining them synergistically with chemically similar or different compounds. While most studies investigated the anti-cancer effects of combinations of two or three compounds, we used more comprehensive mixtures of specific polyphenols and mixtures of polyphenols with vitamins, amino acids and other micronutrients. The mixture containing quercetin, curcumin, green tea, cruciferex, and resveratrol (PB) demonstrated significant inhibition of the growth of Fanconi anemia head and neck squamous cell carcinoma and dose-dependent inhibition of cell proliferation, matrix metalloproteinase (MMP)-2 and -9 secretion, cell migration and invasion through Matrigel. PB was found effective in inhibition of fibrosarcoma HT-1080 and melanoma A2058 cell proliferation, MMP-2 and -9 expression, invasion through Matrigel and inducing apoptosis, important parameters for cancer prevention. A combination of polyphenols (quercetin and green tea extract) with vitamin C, amino acids and other micronutrients (EPQ) demonstrated significant suppression of ovarian cancer ES-2 xenograft tumor growth and suppression of ovarian tumor growth and lung metastasis from IP injection of ovarian cancer A-2780 cells. The EPQ mixture without quercetin (NM) also has shown potent anticancer activity in vivo and in vitro in a few dozen cancer cell lines by inhibiting tumor growth and metastasis, MMP-2 and -9 secretion, invasion, angiogenesis, and cell growth as well as induction of apoptosis. The presence of vitamin C, amino acids and other micronutrients could enhance inhibitory effect of epigallocatechin gallate (EGCG) on secretion of MMPs. In addition, enrichment of NM with quercetin (EPQ mix) enhanced anticancer activity of NM in vivo. In conclusion, polyphenols, especially in combination with other polyphenols or micronutrients, have been shown to be effective against multiple targets in cancer development and progression, and should be considered as safe and effective approaches in cancer prevention and therapy.

Nutrients. 2016;8(9). Epub 2016 Sep 9. PMID: 27618095


These observations thus demonstrated anti-adipogenic effect of EGCG with a possibility of its role in the therapeutic intervention of obesity.

Epigallocatechin gallate (EGCG) is a major component of green tea polyphenols having a potent anti-oxidant potential. Besides inhibiting the growth of many cancer cell types and inducing proliferation and differentiation in keratinocytes, it has been shown to promote reduction of body fat. The fact that mesenchymal stem cells (MSCs) have ability to self-renew and differentiate into the cells of mesodermal lineages, such as fat and bone, it is, thus, possible that EGCG may directly be involved in affecting fat metabolism through its effect on mesenchymal stem cells. Hence, with this aim, the present study was designed to determine the effect of EGCG on mouse mesenchymal stem cells, C3H10T1/2 cells differentiation into adipocytes. To understand this process, the cells were incubated with varying concentrations of EGCG (1μM, 5 μM, 10 μM, 50 μM) in the presence and /or absence of adipogenic medium for 9 days. The results demonstrated that, EGCG inhibited the cells proliferation, migration and also prevented their differentiation to adipogenic lineage. These effects were analyzed through the inhibition of wound healing activity, reduction in Oil red O stained cells, together with decrease in the expression of Adipisin gene following EGCG treatment. These observations thus demonstrated anti-adipogenic effect of EGCG with a possibility of its role in the therapeutic intervention of obesity.

J Stem Cells Regen Med. 2016 ;12(1):16-24. Epub 2016 May 30. PMID: 27397998


At least five servings of vegetables and fruit daily appear protective against breast cancer recurrence.

Evidence from numerous observational and clinical studies suggest that polyphenolic phytochemicals such as phenolic acids in olive oil, flavonols in tea, chocolate and grapes, and isoflavones in soy products reduce the risk of breast cancer. A dietary food pattern naturally rich in polyphenols is the Mediterranean diet and evidence suggests those of Mediterranean descent have a lower breast cancer incidence. Whilst dietary polyphenols have been the subject of breast cancer risk-reduction, this review will focus on the clinical effects of polyphenols on reducing recurrence. Overall, we recommend breast cancer patients consume a diet naturally high in flavonol polyphenols including tea, vegetables (onion, broccoli), and fruit (apples, citrus). At least five servings of vegetables and fruit daily appear protective. Moderate soy protein consumption (5-10 g daily) and the Mediterranean dietary pattern show the most promise for breast cancer patients. In this review, we present an overview of clinical trials on supplementary polyphenols of dietary patterns rich in polyphenols on breast cancer recurrence, mechanistic data, and novel delivery systems currently being researched.

Nutrients. 2016 ;8(9). Epub 2016 Sep 6. PMID: 27608040


Quercus Suber L. Cork Extracts Induce Apoptosis in Human Myeloid Leukaemia HL-60 Cells.

Quercus suber L. cork contains a diversity of phenolic compounds, mostly low molecular weight phenols. A rising number of reports support with convergent findings that polyphenols evoke pro-apoptotic events in cancerous cells. However, the literature related to the anti-cancer bioactivity of Q. suber L. cork extractives (QSE) is still limited. Herein, we aim to describe the antitumor potential displayed by cork extractives obtained by different extraction methods in the human promyelocytic leukaemia cells. In order to quantify the effects of QSE on cancer cells viability, phosphatidylserine exposure, caspase-3 activity, mitochondrial membrane potential and cell cycle were evaluated. The results indicated that the QSE present a time-dependent and dose-dependent cytotoxicity in the human promyelocytic leukaemia cells. Such a noxious effect leads these leukaemia cells to their deaththrough apoptotic processes by altering the mitochondrial outer membrane potential, activating caspase-3 and externalizing phosphatidylserine. However, cells cycle progression was not affected by the treatments. This study contributes to open a new way to use this natural resource by exploiting itsanti-cancer properties. Moreover, it opens new possibilities of application of cork by-products, being more efficient in the sector of cork-based agriculture. Copyright © 2015 John Wiley&Sons, Ltd.

Phytother Res. 2015 Aug ;29(8):1180-7. Epub 2015 Jun 5. PMID: 26052936


Theaflavins suppress the growth and metastasis of human hepatocellular carcinoma.

Theaflavins, the major black tea polyphenols, have been reported to exhibit promising antitumor activities in several human cancers. However, the role of theaflavins in hepatocellular carcinoma (HCC) is still unknown. In this study, we found that theaflavins could significantly inhibit proliferation, migration, and invasion, and induce apoptosis in HCC cells in vitro. Furthermore, we found that theaflavins inhibited the growth and metastasis of HCC in an orthotopic model and a lung metastasis model. Immunohistochemical analyses and terminal deoxynucleotidyl transferase dUTP nick end-labeling assays showed that theaflavins could suppress proliferation and induce apoptosis in vivo. Theaflavins also suppressed constitutive and inducible signal transducer and activator of transcription 3 (STAT3) phosphorylation. The downstream proteins regulated by STAT3, including the antiapoptotic proteins (Bcl-2 and Survivin) and the invasion-related proteins (MMP-2, MMP-9), were also downregulated after theaflavins treatment. Theaflavins induced apoptosis by activating the caspase pathway. Together, our results suggest that theaflavins suppress the growth and metastasis of human HCC through the blockage of the STAT3 pathway, and thus may act as potential therapeutic agents for HCC.

Onco Targets Ther. 2016 ;9:4265-75. Epub 2016 Jul 14. PMID: 27478384


This study highlights the chemo-preventive and chemo-sensitizing role of curcumin in leukemia cells.

Curcumin, a polyphenolic compound isolated from the rhizomes of an herbaceous perennial plant, Curcuma longa, is known to possess anticancerous activity. However, the mechanism of apoptosis induction in cancers differs. In this study, we have (1) investigated the anticancerous activity of curcumin on REH and RS4;11 leukemia cells and (2) studied the chemo-sensitizing potential of curcumin for doxorubicin, a drug presently used for leukemia treatment. It was found that curcumin induced a dose dependent decrease in cell viability because of apoptosis induction as visualized by annexin V-FITC/ PI staining. Curcumin-induced apoptosis of leukemia cells was mediated by PARP-1 cleavage. An increased level of caspase-3, apoptosis inducing factor (AIF), cleaved PARP-1 and decreased level of Bcl2 was observed in leukemia cells after 24h of curcumin treatment. In addition, curcumin at doses lower than the IC50 value significantly enhanced doxorubicin induced cell death. Therefore, we conclude that curcumin induces apoptosis in leukemia cells via PARP-1 mediated caspase-3 dependent pathway and further may act as a potential chemo-sensitizing agent for doxorubicin. Our study highlights the chemo-preventive and chemo-sensitizing role of curcumin.

Asian Pac J Cancer Prev. 2016 ;17(8):3865-9. PMID: 27644631


This review summarizes the epigenetic mechanisms by which active compounds from Chinese herbs exert their anti-cancer effect.

Epigenetic modifications include DNA methylation, histone modification, and other patterns. These processes are associated with carcinogenesis and cancer progression. Thus, epigenetic modification-related enzymes, such as DNA methyltransferases (DNMTs), histone methyltransferases (HMTs), histone demethylases (HDMTs), histone acetyltransferases (HATs), and histone deacetylases (HDACs), as well as some related proteins, including methyl-CpG binding proteins (MBPs) and DNMT1-associated protein (DMAP 1), are considered as potential targets for cancer prevention and therapy. Numerous natural compounds, mainly derived from Chinese herbs and chemically ranging from polyphenols and flavonoids to mineral salts, inhibit the growth and development of various cancers by targeting multiple genetic and epigenetic alterations. This review summarizes the epigenetic mechanisms by which active compounds from Chinese herbs exert their anti-cancer effect. A subset of these compounds, such as curcumin and resveratrol, affect multiple epigenetic processes, including DNMT inhibition, HDAC inactivation, MBP suppression, HAT activation, and microRNA modulation. Other compounds also regulate epigenetic modification processes, but the underlying mechanisms and clear targets remain unknown. Accordingly, further studies are required.

Pharmacol Res. 2016 Sep 30. Epub 2016 Aug 30. PMID: 27697644


Punicalagin may have cancer-chemopreventive as well as cancer-chemotherapeutic effects against human ovarian cancer.

AIM: The aim of this study was to investigate the effects of punicalagin, a polyphenol isolated from Punica granatum, on human A2780 ovarian cancer cells in vitro.METHODS: The viability of human A2780 ovarian cells was evaluated using Cell Counting Kit-8 assay. Cell cycle was detected with flow cytometry analysis. The protein expression levels of Bcl-2, Bax,β-catenin, cyclin D1, survivin, tissue inhibitor of metalloproteinase (TIMP)-2, and TIMP-3 were measured using Western blot analysis. Matrix metalloproteinase (MMP)-2 and MMP-9 activity was determined with gelatin zymography. Wound healing assay was used to determine cell migration.RESULTS: Punicalagin inhibited the cell viability of A2780 cells in a dose- and time-dependent manner, and the cell cycle of A2780 cells was arrested in G1/S phase transition. The treatment also induced apoptosis as shown by the up-regulation of Bax and down-regulation of Bcl-2. On the other hand, punicalagin treatment increased the expressions of TIMP-2 and TIMP-3, decreased the activities of MMP-2 and MMP-9, and inhibited cell migration. In addition, theβ-catenin pathway was suppressed as shown by the down-regulations of β-catenin and its downstream factors including cyclin D1 and survivin.CONCLUSIONS: Punicalagin may have cancer-chemopreventive as well as cancer-chemotherapeutic effects against human ovarian cancer in humans through the inhibition ofβ-catenin signaling pathway.This is an open-access article distributed under the terms of the Creative Commons Attribution-Non Commercial-No Derivatives License 4.0 (CCBY-NC-ND), where it is permissible to download and share the work provided it is properly cited. The work cannot be changed in anyway or used commercially.

Int J Gynecol Cancer. 2016 Aug 19. Epub 2016 Aug 19. PMID: 27540692


A review of the absorption and metabolism process of EGCG and its anti-cancer effect in vitro and in vivo.

Green tea is one of the most popular beverages in the world, especially in Asian countries. Consumption of green tea has been demonstrated to possess many health benefits, which mainly attributed to the main bioactive compound epigallocatechin gallate (EGCG), a flavone-3-ol polyphenol, in green tea. EGCG is mainly absorbed in the intestine, and gut microbiota play a critical role in its metabolism prior to absorption. EGCG exhibits versatile bioactivities, with its anti-cancer effect most attracting due to the cancer preventive effect of green tea consumption, and a great number of studies intensively investigated its anti-cancer effect. In this review, we therefore, first stated the absorption and metabolism process of EGCG, and then summarized its anti-cancer effect in vitro and in vivo, including its manifold anti-cancer actions and mechanisms, especially its anti-cancer stem cell effect, and next highlighted its various molecular targets involved in cancer inhibition. Finally, the anti-cancer effect of EGCG analogs and nanoparticles, as well as the potential cancer promoting effect of EGCG were also discussed. Understanding of the absorption, metabolism, anti-cancer effect and molecular targets of EGCG can be of importance to better utilize it as a chemopreventive and chemotherapeutic agent.

Crit Rev Food Sci Nutr. 2016 Sep 19:0. Epub 2016 Aug 19. PMID: 27645804


Activation of autophagic flux by epigallocatechin gallate mitigates TRAIL-induced tumor cell apoptosis.

Epigallocatechin gallate (EGCG) is a major polyphenol in green tea. Recent studies have reported that EGCG can inhibit TRAIL-induced apoptosis and activate autophagic flux in cancer cells. However, the mechanism behind these processes is unclear. The present study found that EGCG prevents tumor cell death by antagonizing the TRAIL pathway and activating autophagy flux. Our results indicate that EGCG dose-dependently inhibits TRAIL-induced apoptosis and decreases the binding of death receptor 4 and 5 (DR4 and 5) to TRAIL. In addition, EGCG activates autophagy flux, which is involved in the inhibition of TRAIL cell death. We confirmed that the protective effect of EGCG can be reversed using genetic and pharmacological tools through re-sensitization to TRAIL. The inhibition of autophagy flux affects not only the re-sensitization of tumor cells to TRAIL, but also the restoration of death receptor proteins. This study demonstrates that EGCG inhibits TRAIL-induced apoptosis through the manipulation of autophagic flux and subsequent decrease in number of death receptors. On the basis of these results, we suggest further consideration of the use of autophagy activators such as EGCG in combination anti-tumor therapy with TRAIL.

Oncotarget. 2016 Aug 25. Epub 2016 Aug 25. PMID: 27582540


Ellagic acid may exert a broader spectrum of health benefits than has been demonstrated to date.

Ellagic acid (EA) is a naturally occurring polyphenol found in some fruits and nuts, including berries, pomegranates, grapes, and walnuts. EA has been investigated extensively because of its antiproliferative action in some cancers, along with its anti-inflammatory effects. A growing body of evidence suggests that the intake of EA is effective in attenuating obesity and ameliorating obesity-mediated metabolic complications, such as insulin resistance, type 2 diabetes, nonalcoholic fatty liver disease, and atherosclerosis. In this review, we summarize how intake of EA regulates lipid metabolism in vitro and in vivo, and delineate the potential mechanisms of action of EA on obesity-mediated metabolic complications. We also discuss EA as an epigenetic effector, as well as a modulator of the gut microbiome, suggesting that EA may exert a broader spectrum of health benefits than has been demonstrated to date. Therefore, this review aims to suggest the potential metabolic benefits of consumption of EA-containing fruits and nuts against obesity-associated health conditions.

Adv Nutr. 2016 Sep ;7(5):961-72. Epub 2016 Aug 15. PMID: 27633111


Gallic acid is effective in the inhibition of proliferation and induction of apoptosis in Jurkat cell line.

Leukemia is known as the world's fifth most prevalent cancer. New cytotoxic drugs have created considerable progress in the treatment, but side effects are still the important cause of mortality. Plant derivatives have been recently considered as important sources for the treatment of various diseases, including cancer. Gallic acid (GA) is a polyhydroxyphenolic compound with a wide range of biological functions. The aim of the present study was to evaluate the effect of GA on proliferation inhibition and apoptosis induction of a lymphoblastic leukemia cell line. Jurkat cell (C121) line was cultured in RPMI 1640 supplemented with 10% heat-inactivated fetal bovine serum (FBS) with different concentrations of GA (10, 20, 30, 40, 50, 60, 70, 80, 90, and 100μM) for 24, 48 and 72 hours. The effect of GA on cell viability was measured using MTS assay. Induction of apoptosis was evaluated with Annexin V-FITC/PI kit and flow cytometry. Data were analyzed by SPSS version 20 using Kruskal-Wallis and Dunn's multiple comparison tests. Decline of cell viability to less than 50% was observed at 60.3±1.6, 50.9±1.5, and 30.9±2.8 μM concentration after 24, 48, and 72 hours incubation, respectively. All concentrations of GA (10, 30, 50 and 80 μM) enhanced apoptosis compared to the control (P

Iran J Med Sci. 2016 Nov ;41(6):525-530. PMID: 27853333


These results demonstrate the existence of two conflicting pathways in silibinin-induced death of MCF-7 cells.

Reactive oxygen species (ROS) and reactive nitrogen species (RNS) play important roles in regulating cell survival and death. Silibinin is a natural polyphenolic flavonoid isolated from milk thistle with anti-tumor activities, but it was found to induce cytoprotective ROS/RNS in human breast cancer MCF-7 cells. Furthermore, treatment with silibinin down-regulates ERα expression in MCF-7 cells, and inducing both autophagy and apoptosis. In this study we explored the relationship between ER-associated pathways and RNS/ROS in MCF-7 cells. We also investigated the molecular mechanisms underlying the reciprocal regulation between ROS/RNS levels and autophagy in the death signaling pathways in silibinin-treated MCF-7 cells. Silibinin (100-300 μmol/L) dose-dependently increased ROS/RNS generation in MCF-7 cells (with high expression of ERα and low expression of ERβ) and MDA-MB-231 cells (with low expression of ERα and high expression of ERβ). Scavenging ROS/RNS significantly enhanced silibinin-induced death of MCF-7 cells, but not MDA-MB231 cells. Pharmacological activation or blockade of ERα in MCF-7 cells significantly enhanced or decreased, respectively, silibinin-induced ROS/RNS generation, whereas activation or block of ERβ had no effect. Insilibinin-treated MCF-7 cells, exposure to the ROS/RNS donators decreased the autophagic levels, whereas inhibition of autophagy with 3-MA significantly increased ROS/RNS levels. We further showed that increases in ROS/RNS generation, ERα activation or autophagy down-regulation had protective rolesin silibinin-treated MCF-7 cells. Under a condition of ERα activation, scavenging ROS/RNS or stimulating autophagy enhanced the cytotoxicity of silibinin. These results demonstrate the existence of two conflicting pathways in silibinin-induced death of MCF-7 cells: one involves the down-regulationof ERα and thereby augmenting the pro-apoptotic autophagy downstream, leading to cell death; the other involves the up-regulation of pro-survival ROS/RNS; and that the generation of ROS/RNS and autophagy form a negative feedback loop whose balance is regulated by ERα.

Acta Pharmacol Sin. 2016 Nov 21. Epub 2016 Nov 21. PMID: 27867187


The indirect removal of UVB damaged keratinocytes by herbal tea extracts via apoptosis may find application in the prevention of photo-induced inflammation.

Ultraviolet B (UVB) radiation is one of the major predisposing risk factors of skin cancer. The anticancer and photoprotective effects of unoxidized rooibos (Aspalathus linearis) and honeybush (Cyclopia) herbal teas, containing high levels of dihydrochalones and xanthones, respectively, have been demonstrated in skin cancer models in vivo. In the current study, the anti-inflammatory effects of methanol and aqueous extracts of these herbal teas were investigated in a UVB/HaCaT keratinocyte model with intracellular interleukin-1α (icIL-1α) accumulation as a biomarker. Extracts of green tea (Camellia sinensis) served as benchmark. Both extracts of green tea and rooibos, as well as the aqueous extract of C. intermedia, enhanced UVB-induced inhibition of cell viability, proliferation and induction of apoptosis, facilitatingthe removal of icIL-1α. The underlying mechanisms may involve mitochondrial dysfunction exhibiting pro-oxidant responses via polyphenol-iron interactions. The methanol extracts of honeybush, however, protected against UVB-induced reduction of cell growth parameters, presumably via antioxidant mechanisms that prevented the removal of highly inflamed icIL-1α-containing keratinocytes via apoptosis. The dual antioxidant and/or pro-oxidant role of the polyphenolic herbal tea constituents should be considered in developing preventive strategies against UVB-induced skin carcinogenesis. The indirect removal of UVB damaged keratinocytes by herbal tea extracts via apoptosis may find application in the prevention of photo-induced inflammation.

Molecules. 2016 Oct 2 ;21(10). Epub 2016 Oct 2. PMID: 27706097


A review of curcumin as a multifaceted compound against human papilloma virus infection and cervical cancers

Curcumin, the bioactive polyphenolic ingredient of turmeric, has been extensively studied for its effects on human papilloma virus (HPV) infection as well as primary and malignant squamous cervical cancers. HPV infections, especially those related to HPV 16 and 18 types, have been established as the leading cause of cervical cancer; however, there are also additional contributory factors involved in the etiopathogenesis of cervical cancers. Curcumin has emerged as having promising chemopreventive and anticancer effects against both HPV-related and nonrelated cervical cancers. In this review, we first discuss the biological relevance of curcumin and both its pharmacological effects and pharmaceutical considerations from a chemical point of view. Next, the signaling pathways that are modulated by curcumin and are relevant to the elimination of HPV infection and treatment of cervical cancer are discussed. We also present counter arguments regarding the effects of curcumin on signaling pathways and molecular markers dysregulated by benzo(a)pyrene (Bap), a carcinogen found in pathological cervical lesions of women who smoke frequently, and estradiol, as two important risk factors involved in persistent HPV-infection and cervical cancer. Finally, various strategies to enhance the pharmacological activity and pharmacokinetic characteristics of curcumin are discussed with examples of studies in experimental models of cervical cancer.© 2016 BioFactors, 2016.

Biofactors. 2016 Nov 29. Epub 2016 Nov 29. PMID: 27896883


EGCG exerts significant anti-proliferative effects against renal cell cancer and malignant melanoma cells in vitro.

: e22101 Background: GTE and Epigallocatechin 3-gallate (EGCG), the most abundant polyphenol in GTE, have been shown to exert inhibitory effects on carcinogenesis; modulatory effects on tumor proliferation and differentiation; and immunomodulatory effects on tumor immunity in different pre-clinical models. These pluripotent effects suggest that GTE may have clinical activity that could be exploited for treatment of chemo-insensitive but immunologically responsive tumors. Thus, the present study investigated the effects of EGCG on the proliferation and immunologic sensitivity of human renal cell cancer (RCC) and malignant melanoma (MM) cell lines.METHODS: Human RCC (769-P) and MM (A375) cell lines were tested following incubation in media± 21.8μM EGCG, a pharmacologically-achievable concentration produced by 8, 200mg capsules GTE daily. Tumor proliferation was assessed by MTS assay; lytic sensitivity to IL2-activated human peripheral blood lymphocytes (IL2PBL) by (51)Chromium release assay; and gene expression by quantitative RT-PCR assay.RESULTS: EGCG produced significant inhibition of proliferation of both RCC and MM cells (61.5% and 67.3% of media control values respectively; p

J Clin Oncol. 2009 May 20 ;27(15_suppl):e22101. PMID: 27963498


A pinecone water extract induced apoptosis associated with caspase-3 activation in A549, H1264, H1299, and Calu-6 lung cancer cells.

Pinecones from Pinus koraiensis Siebold&Zucc. (Pinaceae), which have historically been treated as an undesired waste by-product in the processing of seeds, have recently been shown to contain ingredients with potent biological activities, such as polyphenols exhibiting anti-tumor activity. With this study, we seek to broaden our understanding of anti-tumor compounds contained in these pinecones beyond just polyphenols. We found that the water extract of P. koraiensis pinecones exhibits significant anti-cancer activity, with IC50 values ranging from 0.62 to 1.73 mg/mL in four human lung cancer cell lines, A549, H1264, H1299, and Calu-6, irrespective of their p53 status. We also demonstrate that pinecone water extract induces apoptosis associated with caspase-3 activation in the same cancer cell lines. Chemical investigation of the pinecone water extract revealed eight main components (1-8), and their structures were identified as dehydroabietic acid (1), 15-hydroxy-7-oxodehydroabietic acid (2), 7β,15-dihydroxydehydroabietic acid (3), β-D-glucopyranosyl labda-8(17,13)-diene-(15,16)-lactone-19-oate (4), 7α,15-dihydroxydehydroabietic acid (5), (1S,2S,4R)-(+)-limonene-1,2-diol (6), sobrerol (7), and 4-hydroxy-benzoic acid (8). These findings suggest a novel biological application of P. koraiensis pinecones in combatting human lung cancer, and further identify the major compounds that could contribute to this anti-cancer activity. This article is protected by copyright. All rights reserved.

Chem Biodivers. 2016 Dec 27. Epub 2016 Dec 27. PMID: 28027428


P. eldarica could be considered as a potential cytotoxic candidate.

Several attempts have so far been made in the search of new anticancer agents of plant origin. Some studies have reported that different species of Pine genus possess cytotoxic activities against various cancer cell lines. In the present study, we evaluated the cytotoxic effects of Pinus eldarica bark and leaf extracts or leaf essential oil on HeLa and MCF-7 tumor cell lines. Hydroalcoholic and phenolic extracts and the essential oil of plant were prepared. Total phenolic contents of the extracts were measured using Folin-Ciocalteu reagent. Essential oil components were determined by gas chromatography-mass spectroscopy (GC-MS). Cytotoxic activity of the extracts and essential oil against HeLa and MCF-7 tumor cell lines were assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay. The polyphenolic content of hydroalcoholic and phenolic extracts of the bark and hydroalcoholic extract of the leaf were 48.31%, 47.2%, and 8.47%, respectively. According to the GC-MS analysis, the major components of the leaf oil of P. eldarica were:β -caryophyllene (14.8%), germacrene D (12.9%), α-terpinenyl acetate (8.15%), α -pinene (5.7%), and -α humulene (5.9%). Bark extracts and leaf essential oil of P. eldarica significantly reduced the viability of both HeLa and MCF-7 cells in a concentration dependent manner. However, leaf extractshowed less inhibitory effects against both cell lines. The essential oil of P. eldarica was more cytotoxic than its hydroalcoholic and phenolic extracts. The terpenes and phenolic compounds were probably responsible for cytotoxicity of P. eldarica. Therefore, P. eldarica might have a good potentialfor active anticancer agents.

Res Pharm Sci. 2016 Dec ;11(6):476-483. PMID: 28003841


Curcumin is a potentially powerful tool to reverse cisplatin-induced toxicity.

Curcumin is a naturally occurring polyphenol isolated from Curcuma longa that has gained considerable interest over the last decades due to its beneficial effects for human health. Moreover, the usage of cisplatin, a platinum-based chemotherapeutic, is associated with several adverse effects affecting the quality of life of the patients. Also, cisplatin therapy is jeopardized by a great challenge of resistance which reduces the efficacy of this drug. In order to conquer these dark sides of cisplatin therapy, curcumin has been widely used to fight against cisplatin-resistant cancer cells and decrease its unwanted side effects (e.g. ototoxicity, nephrotoxicity and neurotoxicity). In this review, we provide a summary of the studies done to show the protective effects of curcumin against cisplatin failure and toxicity.

Pharmacol Res. 2016 Dec 29. Epub 2016 Dec 29. PMID: 28042086


Lotus leaf extract might be useful for treatment in therapy-resistance triple negative breast cancer.

ETHNOPHARMACOLOGICAL RELEVANCE: Nelumbo nucifera Gaertn (Nymphaeaceae) has been recognized as a medicinal plant, which was distributed throughout the Asia. The aqueous extract of Nelumbo nucifera leaves extract (NLE) has various biologically active components such as polyphenols, flavonoids, oligomeric procyanidines. However, the role of NLE in breast cancer therapy is poorly understood.THE AIM OF THIS STUDY: The purpose of this study was to identify the hypothesis that NLE can suppress tumor angiogenesis and metastasis through CTGF (connective tissue growth factor), which has been implicated in tumor angiogenesis and progression in breast cancer MDA-MB-231 cells.RESULTS: We examined the effects of NLE on angiogenesis in the chicken chorioallantoic membrane (CAM) model. The data showed that NLE could reduce the chorionic plexus at day 17 in CAM and the duration of this inhibition was dose-dependent. In Xenograft model, NLE treatment significantly reduced tumor weight and CD31 (capillary density) over control, respectively. We examined the role of angiogenesis involved restructuring of endothelium using human umbilical vein endothelial cell (HUVEC) in Matrigel angiogenesis model. The results indicated that vascular-like structure formation was further blocked by NLE treatment. Moreover, knockdown of CTGF expression markedly reduced the expression of MMP2 as well as VEGF, and attenuated PI3K-AKT-ERK activation, indication that these signaling pathways are crucial in mediating CTGF function.CONCLUSION: The present results suggest that NLE might be useful for treatment in therapy-resistance triple negative breast cancer.

J Ethnopharmacol. 2016 Jul 21 ;188:111-22. Epub 2016 May 10. PMID: 27178635


High altitude saxicolous lichens can be an interesting source of new antioxidative substrates.

Fourteen saxicolous lichens from trans-Himalayan Ladakh region were identified by morpho-anatomical and chemical characteristics. The n-hexane, methanol and water extracts of the lichens were evaluated for their antioxidant capacities. The lichen extracts showing high antioxidant capacities and rich phenolic content were further investigated to determine their cytotoxic activity on human HepG2 and RKO carcinoma cell lines. The ferric reducing antioxidant power (FRAP), 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS), 1,1-diphenyl-2-picrylhydrazyl (DPPH) and nitric oxide (NO) radical scavenging capacities andβ-carotene-linoleic acid bleaching property exhibited analogous results where the lichen extracts showed high antioxidant action. The lichen extracts were also found to possess good amount of total proanthocyanidin, flavonoid and polyphenol. The methanolic extract of Lobothallia alphoplaca exhibited highest FRAP value. Methanolic extract of Xanthoparmelia stenophylla showed the highest ABTS radical scavenging capacity. The n-hexane extract of Rhizoplaca chrysoleuca exhibited highest DPPH radical scavenging capacity. Highest antioxidant capacity in terms of β-carotene linoleic acid bleachingproperty was observed in the water extract of Xanthoria elegans. Similarly, Melanelia disjuncta water extract showed highest NO scavenging capacity. Among n-hexane, methanol and water extracts of all lichens, the methanolic extract of Xanthoparmelia mexicana showed highest total proanthocyanidin, flavonoid and polyphenol content. From cytotoxic assay, it was observed that the methanolic extracts of L. alphoplaca and M. disjuncta were exhibiting high cytotoxic effects against cancer cell growth. Similarly, the water extract of Dermatocarpon vellereum, Umbilicaria vellea, X. elegans and M. disjuncta and the methanolic extract of M. disjuncta and X. stenophylla were found to possess high antioxidant capacities and were non-toxic and may be used as natural antioxidants for stress related problems. Our studies go on to prove that the unique trans-Himalayan lichens are a hitherto untapped bioresource with immense potential for discovery of new chemical entities, and this biodiversity needs to be tapped sustainably.

PLoS One. 2014 ;9(6):e98696. Epub 2014 Jun 17. PMID: 24937759


Physodic acid and acetone extract from H. physodes displayed cytotoxic effects in the breast cancer cell lines.

CONTEXT: Lichens produce specific secondary metabolites with different biological activity. OBJECTIVE: This study investigated the cytotoxic effects of physodic acid, in addition to the total phenolic content and cytotoxic and antioxidant activity of acetone extract from Hypogymnia physodes (L.) Nyl. (Parmeliaceae). MATERIALS AND METHODS: Cytotoxicity of physodic acid (0.1-100 μM) was assessed in MDA-MB-231, MCF-7 and T-47D breast cancer cell lines and a nontumorigenic MCF-10A cell line using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, neutral red uptake and crystal violet assays during 72 h of incubation. An MTT assay was also used to assess the cytotoxic effects of the acetone extract (0.1-100 μg/mL) in the MDA-MB-231, MCF-7, T-47D breast cancer cell lines after 72 h. The total phenolic content of the acetone extract, expressed as the gallic acid equivalent, was investigated using Folin-Ciocalteu reagent. The antioxidant activity of the extract was assessed by 2,2-diphenyl-1-picrylhydrazyl and ferric-reducing antioxidant power assays. RESULTS: The cytotoxic activity of physodic acid appeared to be strong in the tumorigenic cell lines (IC50 46.0-93.9 μM). The compound was inactive against the nontumorigenic MCF-10A cell line (IC50 >100 μM). The acetone extract showed cytotoxicity in the breast cancer cell lines (IC50 46.2-110.4 μg/mL). The acetone extract was characterized by a high content of polyphenols, and it had significant antioxidant activity. DISCUSSION AND CONCLUSION: Physodic acid and acetone extract from H. physodes displayed cytotoxic effects in the breast cancer cell lines. Furthermore, acetone extract from H. physodes possessed significant antioxidant properties.

Pharm Biol. 2016 Nov ;54(11):2480-2485. Epub 2016 Apr 6. PMID: 27049956


Many dietary phytochemicals are shown to modify and reverse aberrant epigenetic changes, potentially leading to cancer prevention or treatment.

Oxidative stress occurs when cellular reactive oxygen species levels exceed the self-antioxidant capacity of the body. Oxidative stress induces many pathological changes, including inflammation and cancer. Chronic inflammation is believed to be strongly associated with the major stages of carcinogenesis. The nuclear factor erythroid 2-related factor 2 (Nrf2) pathway plays a crucial role in regulating oxidative stress and inflammation by manipulating key antioxidant and detoxification enzyme genes via the antioxidant response element. Many dietary phytochemicals with cancer chemopreventive properties, such as polyphenols, isothiocyanates, and triterpenoids, exert antioxidant and anti-inflammatory functions by activating the Nrf2 pathway. Furthermore, epigenetic changes, including DNA methylation, histone post-translational modifications, and miRNA-mediated post-transcriptional alterations, also lead to various carcinogenesis processes by suppressing cancer repressor gene transcription. Using epigenetic research tools, including next-generation sequencing technologies, many dietary phytochemicals are shown to modify and reverse aberrant epigenetic/epigenome changes, potentially leading to cancer prevention/treatment. Thus, the beneficial effects of dietary phytochemicals on cancer development warrant further investigation to provide additional impetus for clinical translational studies.

Chem Res Toxicol. 2016 Dec 19 ;29(12):2071-2095. Epub 2016 Dec 5. PMID: 27989132


P. sidoides has cancer cell type-specific anti-proliferative effects and may be a source of novel anticancer molecules.

Context Pelargonium sidoides DC (Geraniaceae) is an important medicinal plant indigenous to South Africa and Lesotho. Previous studies have shown that root extracts are rich in polyphenolic compounds with antibacterial, antiviral and immunomodulatory activities. Little is known regarding the anticancer properties of Pelargonium sidoides extracts. Objective This study evaluates the anti-proliferative effects of a Pelargonium sidoides radix mother tincture (PST). Materials and methods The PST was characterized by LC-MS/MS. Anti-proliferative activity was evaluated in the pre-screen panel of the National Cancer Institute (NCI-H460, MCF-7 and SF-268) and the Jurkat leukaemia cell line at concentrations of 0-150 μg/mL. The effect on cell growth was determined with sulphorhodamine B and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assays after 72 h. The effect on cell cycle and apoptosis induction in Jurkat cells was determined by flow cytometry with propidium iodide and Annexin V: fluorescein isothiocyanate staining. Results Dihydroxycoumarin sulphates, gallic acid as well as gallocatechin dimers and trimers were characterized in PST by mass spectrometry. Moderate anti-proliferative effects with GI50 values between 40 and 80 μg/mL were observed in the NCI-pre-screen panel. Strong activity observed with Jurkat cells with a GI50 value of 6.2 μg/mL, significantly better than positive control 5-fluorouracil (GI50 value of 9.7 μg/mL). The PST arrested Jurkat cells at the G0/G1 phase of the cell cycle and increased the apoptotic cells from 9% to 21%, while the dead cellsincreased from 4% to 17%. Conclusion We present evidence that P. sidoides has cancer cell type-specific anti-proliferative effects and may be a source of novel anticancer molecules.

Pharm Biol. 2016 Sep ;54(9):1831-40. Epub 2016 Jan 21. PMID: 26794080


Delphinidin has a potentially new role in anti angiogenic action by inhibiting HIF-1α and VEGF expression.

Delphinidin, a polyphenol that belongs to the group of anthocyanidins and is abundant in many pigmented fruits and vegetables, possesses important antioxidant, anti‑inflammatory, anti-mutagenic and anticancer properties. In the present study, we investigated the inhibitory effects of delphinidin on vascular endothelial growth factor (VEGF) expression, an important factor involved in angiogenesis and tumor progression, in A549 human lung cancer cells. Delphinidin inhibited CoCl2- and epidermal growth factor (EGF)-induced VEGF mRNA expression and VEGF protein production. Delphinidin also decreased CoCl2- and EGF-stimulated expression of hypoxia‑inducible factor (HIF)‑1α, which is a transcription factor of VEGF. Delphinidin suppressed CoCl2- and EGF-induced hypoxia‑response element (HRE) promoter activity, suggesting that the inhibitory effects of delphinidin on VEGF expression are caused by the suppression of the binding of HIF-1 to the HRE promoter. We also found that delphinidin specifically decreased the CoCl2- and EGF-induced HIF-1α protein expression by blocking the ERK and PI3K/Akt/mTOR/p70S6K signaling pathways, whereas the p38-mediated pathways were not involved. In animal models, EGF-induced new blood vessel formation was significantly inhibited by delphinidin. Therefore, our results indicate that delphinidin has a potentially new role in anti‑angiogenic action by inhibiting HIF-1α and VEGF expression.

Oncol Rep. 2016 Dec 7. Epub 2016 Dec 7. PMID: 27959445


Peels and flesh extract of Sour-YRP significantly inhibited the proliferation of HepG2 and Hela cancer cells lines.

Plant polyphenols derived from pomegranates are natural health-promoting components, and their bioactivities are well proved. However, the systematic studies of polyphenols constituents and cytotoxic ability in fruit parts of pomegranates derived from different Chinese cultivars have not been studied yet. In this report, a validated and sensitive HPLC-DAD method and fluorescence spectrophotometric method was established for quantitative analysis of four polyphenols and total phenolic content (TPC) in fruit parts of pomegranates (including peels, flesh, seeds, juices and leaves) derived from five Chinese cultivars, respectively. HPLC analysis was performed on the YMC ODS-A C18 column with gradient elution of MeOH and 0.1 % TFA. Four polyphenols including gallic acid, ellagic acid, punicalagin A&B and punicalin A&B exhibited satisfactory linearity in the concentration ranges of 20-320, 39-624, 74-1184 and 38-608 μg/mL, respectively. The results demonstrated that the amounts of TPC and four polyphenols in different fruit parts of pomegranates varied significantly. Peels of Sour-YRP possessed the highest content of punicalagin A&B (125.23 mg/g), whereas other three polyphenols exhibited only trace. Among the five Chinese cultivars, Sour-YRP contained the highest content of TPC (688.61 mg/g) and could be considered as the desirable botanical source to obtain polyphenols. It is also discovered that low-maturity pomegranate might possessed much higher TPC than high-maturity pomegranate. The optimized HPLC-DAD method could be used for quality control of different pomegranates by identification and quantification of its main polyphenolic components. Furthermore, the in vitro cytotoxicity of different pomegranates fruit parts to cancer cells was evaluated. We discovered that peels and flesh extract of Sour-YRP significantly inhibited the proliferation of HepG2 and Hela cancer cells lines. The results of this work are promising for further investigation and development of pomegranates as therapeutic agent for the treatment ofcancer.

Springerplus. 2016 ;5(1):914. Epub 2016 Jun 29. PMID: 27386358


Resveratrol and piceatannol selectively trigger death in cancer but not somatic cells.

BACKGROUND/AIMS: Resveratrol and its derivate piceatannol are known to induce cancer cell-specific cell death. While multiple mechanisms of actions have been described including the inhibition of ATP synthase, changes in mitochondrial membrane potential and ROS levels, the exact mechanisms of cancer specificity of these polyphenols remain unclear. This paper is designed to reveal the molecular basis of the cancer-specific initiation of cell death by resveratrol and piceatannol.METHODS: The two cancer cell lines EA.hy926 and HeLa, and somatic short-term cultured HUVEC were used. Cell viability and caspase 3/7 activity were tested. Mitochondrial, cytosolic and endoplasmic reticulum Ca2+ as well as cytosolic and mitochondrial ATP levels were measured using single cell fluorescence microscopy and respective genetically-encoded sensors. Mitochondria-ER junctions were analyzed applying super-resolution SIM and ImageJ-based image analysis.RESULTS: Resveratrol and piceatannol selectively trigger death in cancer but not somatic cells. Hence, these polyphenols strongly enhanced mitochondrial Ca2+ uptake in cancer exclusively. Resveratrol and piceatannol predominantly affect mitochondrial but not cytosolic ATP content that yields in a reduced SERCA activity. Decreased SERCA activity and the strongly enriched tethering of the ER and mitochondria in cancer cells result in an enhanced MCU/Letm1-dependent mitochondrial Ca2+ uptake upon intracellular Ca2+ release exclusively in cancer cells. Accordingly, resveratrol/piceatannol-induced cancer cell death could be prevented by siRNA-mediated knock-down of MCU and Letm1.CONCLUSIONS: Because their greatly enriched ER-mitochondria tethering, cancer cells are highly susceptible for resveratrol/piceatannol-induced reduction of SERCA activity to yield mitochondrial Ca2+ overload and subsequent cancer cell death.

Cell Physiol Biochem. 2016 ;39(4):1404-20. Epub 2016 Sep 9. PMID: 27606689


Animal experimentation and cocoa interventions in humans support the anti-inflammatory effect of cocoa compounds.

Chronic inflammation has been identified as a necessary step to mediate atherosclerosis and cardiovascular disease and as a relevant stage in the onset and progression of several types of cancer. Considerable attention has recently been focused on the identification of dietary bioactive compounds with anti-inflammatory activities as an alternative natural source for prevention of inflammation-associated diseases. The remarkable capacity of cocoa flavanols as antioxidants, as well as to modulate signaling pathways involved in cellular processes, such as inflammation, metabolism and proliferation, has encouraged research on this type of polyphenols as useful bioactive compounds for nutritional prevention of cardiovascular disease and cancer. Data from numerous studies suggest that cocoa and cocoa-derived flavanols can effectively modify the inflammatory process, and thus potentially provide a benefit to individuals with elevated risk factors for atherosclerosis/cardiovascular pathology and cancer. The present overview will focus on the most recent findings about the effects of cocoa, its main constituents and cocoa derivatives on selected biomarkers of the inflammatory process in cell culture, animal models and human cohorts.

Nutrients. 2016 Apr 9 ;8(4):212. Epub 2016 Apr 9. PMID: 27070643


Baicalein and luteolin could inhibit proliferation and induce apoptosis in colon cancer cells.

Due to the type-specific diversity of cancer cells, an analysis and elucidation of molecular mechanisms responsible for anticancer properties of biologically active compounds are essential. Plant-derived polyphenolic compounds such as flavonoids may be useful in cancer chemoprevention or treatment because they influence diverse molecular pathways in cancer cells. In these studies anticancer activity of natural occurring flavones, baicalein and luteolin was investigated in colon cancer cells LoVo and in their drug resistant subline LoVo/Dx. Inhibitory activity of these flavones on cells growth and their ability to induce apoptosis were observed. A less pronounced influence of studied flavones on proliferation and apoptosis of LoVo/Dx as compared with LoVo cells well correlated with significantly lower cytotoxicity of these compounds in drug-resistant cells. These effects may be related to overexpression of multidrug transporter P-glycoprotein in drug-resistant LoVo/Dx cells. Our studies indicated that baicalein could be a substrate of this drug transporter.

Biomed Pharmacother. 2017 Jan 19 ;88:232-241. Epub 2017 Jan 19. PMID: 28110189


The present knowledge on the role of flavonoids in chemoprevention can be used in developing effective dietary strategies.

Carcinogenesis is a multistage process that involves a series of events comprising of genetic and epigenetic changes leading to the initiation, promotion and progression of cancer. Chemoprevention is referred to as the use of nontoxic natural compounds, synthetic chemicals or their combinations to intervene in multistage carcinogenesis. Chemoprevention through diet modification, i.e., increased consumption of plant-based food, has emerged as a most promising and potentially cost-effective approach to reducing the risk of cancer. Flavonoids are naturally occurring polyphenols that are ubiquitous in plant-based food such as fruits, vegetables and teas as well as in most medicinal plants. Over 10,000 flavonoids have been characterized over the last few decades. Flavonoids comprise of several subclasses including flavonols, flavan-3-ols, anthocyanins, flavanones, flavones, isoflavones and proanthocyanidins. This review describes the most efficacious plant flavonoids, including luteolin, epigallocatechin gallate, quercetin, apigenin and chrysin; their hormetic effects; and the molecular basis of how these flavonoids contribute to the chemoprevention with a focus on protection against DNA damage caused by various carcinogenic factors. The present knowledge on the role of flavonoids in chemoprevention can be used in developing effective dietary strategies and natural health products targeted for cancer chemoprevention.

J Nutr Biochem. 2016 Nov 28 ;45:1-14. Epub 2016 Nov 28. PMID: 27951449


Fermented chamomile with Lactobacillus plantarum has improved antioxidative and cytotoxic activities.

Antioxidative and cytotoxic effects of chamomile (Matricaria chamomilla) fermented by Lactobacillus plantarum were investigated to improve their biofunctional activities. Total polyphenol (TP) content was measured by the Folin-Denis method, and the antioxidant activities were assessed by the 1,1-diphenyl-2-picrylhydrazyl (DPPH) method andβ-carotene bleaching method. AGS, HeLa, LoVo, MCF-7, and MRC-5 (normal) cells were used to examine the cytotoxic effects by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium (MTT) assay. The TP content of fermented chamomile reduced from 21.75 to 18.76 mg gallic acid equivalent (mg GAE)/g, but the DPPH radical capturing activity of fermented chamomile was found to be 11.1% higher than that of nonfermented chamomile after 72 h of fermentation. Following the β-carotene bleaching, the antioxidative effect decreased because of a reduction in pH during fermentation. Additionally, chamomile fermented for 72 h showed a cytotoxic effect of about 95% against cancer cells at 12.7 mg solid/ml of broth, but MRC-5 cells were significantly less sensitive against fermented chamomile samples. These results suggest that the fermentation of chamomile could be applied to develop natural antioxidativeand anticancer products.

J Zhejiang Univ Sci B. 2017 Feb.;18(2):152-160. PMID: 28124843


Quercetin induces MiR-200b-3p which could inhibit cancer stem cells self-renewal and proliferation.

BACKGROUND: Cancer stem cells are suggested to contribute to the extremely poor prognosis of pancreatic ductal adenocarcinoma and dysregulation of symmetric and asymmetric stem cell division may be involved. Anticancer benefits of phytochemicals like the polyphenol quercetin, present in many fruits, nuts and vegetables, could be expedited by microRNAs, which orchestrate cell-fate decisions and tissue homeostasis. The mechanisms regulating the division mode of cancer stem cells in relation to phytochemical-induced microRNAs are poorly understood.METHODS: Patient-derived pancreas tissue and 3 established pancreatic cancer cell lines were examined by immunofluorescence and time-lapse microscopy, microRNA microarray analysis, bioinformatics and computational analysis, qRT-PCR, Western blot analysis, self-renewal and differentiation assays.RESULTS: We show that symmetric and asymmetric division occurred in patient tissues and in vitro, whereas symmetric divisions were more extensive. By microarray analysis, bioinformatics prediction and qRT-PCR, we identified and validated quercetin-induced microRNAs involved in Notch signaling/cell-fate determination. Further computational analysis distinguished miR-200b-3p as strong candidate for cell-fate determinant. Mechanistically, miR-200b-3p switched symmetric to asymmetric cell division by reversing the Notch/Numb ratio, inhibition of the self-renewal and activation of the potential to differentiate to adipocytes, osteocytes and chondrocytes. Low miR-200b-3p levels fostered Notch signaling and promoted daughter cells to become symmetric while high miR-200b-3p levels lessened Notch signaling and promoted daughter cells to become asymmetric.CONCLUSIONS: Our findings provide a better understanding of the cross talk between phytochemicals, microRNAs and Notch signaling in the regulation of self-renewing cancer stem cell divisions.

Mol Cancer. 2017 Jan 31 ;16(1):23. Epub 2017 Jan 31. PMID: 28137273


Phytochemicals which inhibit cancer stem cells may prove to be promising agents for the prevention and treatment of pancreatic cancers.

Pancreatic ductal adenocarcinoma is one of the deadliest cancers worldwide and the fourth leading cause of cancer-related deaths in United States. Regardless of the advances in molecular pathogenesis and consequential efforts to suppress the disease, this cancer remains a major health problem in United States. By 2030, the projection is that pancreatic cancer will be climb up to be the second leading cause of cancer-related deaths in the United States. Pancreatic cancer is a rapidly invasive and highly metastatic cancer, and does not respond to standard therapies. Emerging evidence support that the presence of a unique population of cells called cancer stem cells (CSCs) as potential cancer inducing cells and efforts are underway to develop therapeutic strategies targeting these cells. CSCs are rare quiescent cells, and has the capacity to self-renew through asymmetric/symmetric cell division, as well as differentate into various lineages of cells in the cancer. Studies have been shown that CSCs are highly resistant to standard therapy and also responsible for drug resistance, cancer recurrence and metastasis. To overcome of this problem, we need novel preventive agents that target these CSCs. Natural compounds or phytochemicals have ability to target for these CSCs and their signaling pathways. Therefore, in the present review article, we summarize our current understanding of pancreatic CSCs and their signaling pathways, and the phytochemicals that target these cells including curcumin, resveratrol, tea polyphenol EGCG (epigallocatechin-3-gallate), crocetinic acid, sulforaphane, genistein, indole-3-carbinol, vitamin Eδ-tocotrienol, Plumbagin, quercetin, triptolide, Licofelene and Quinomycin. These natural compounds or phytochemicals, which inhibit cancer stem cells may prove to be promising agents for the prevention and treatment of pancreatic cancers.

Curr Med Chem. 2017 Jan 26. Epub 2017 Jan 26. PMID: 28137215


The anthocyanins, proanthocyanidins, and flavonol glycosides within the cranberry extract have a synergistic or additive antiproliferative effect.

Cranberries (Vaccinium macrocarpon Ait.) are an excellent dietary source of phytochemicals that include flavonol glycosides, anthocyanins, proanthocyanidins (condensed tannins), and organic and phenolic acids. Using C-18 and Sephadex Lipophilic LH-20 column chromatography, HPLC, and tandem LC-ES/MS, the total cranberry extract (TCE) has been analyzed, quantified, and separated into fractions enriched in sugars, organic acids, total polyphenols, proanthocyanidins, and anthocyanins (39.4, 30.0, 10.6, 5.5, and 1.2% composition, respectively). Using a luminescent ATP cell viability assay, the antiproliferative effects of TCE (200 microg/mL) versus all fractions were evaluated against human oral (KB, CAL27), colon (HT-29, HCT116, SW480, SW620), and prostate (RWPE-1, RWPE-2, 22Rv1) cancer cell lines. The total polyphenol fraction was the most active fraction against all cell lines with 96.1 and 95% inhibition of KB and CAL27 oral cancer cells, respectively. For the colon cancer cells, the antiproliferative activity of this fraction was greater against HCT116 (92.1%) than against HT-29 (61.1%), SW480 (60%), and SW620 (63%). TCE and all fractions showed>/=50% antiproliferative activity against prostate cancer cells with total polyphenols being the most active fraction (RWPE-1, 95%; RWPE-2, 95%; 22Rv1, 99.6%). Cranberry sugars (78.8 microg/mL) did not inhibit the proliferation of any cancer cell lines. The enhanced antiproliferative activity of total polyphenols compared to TCE and its individual phytochemicals suggests synergistic or additive antiproliferative interactions of the anthocyanins, proanthocyanidins, and flavonol glycosides within the cranberry extract.

J Agric Food Chem. 2004 May 5 ;52(9):2512-7. PMID: 15113149


Ellagic acid inhibits the proliferation of human pancreatic carcinoma PANC-1 cells.

Ellagic aicd (EA), a dietary polyphenolic compound found in plants and fruits, possesses various pharmacological activities. This study investigated the effect of EA on human pancreatic carcinoma PANC-1 cells both in vitro and in vivo; and defined the associated molecular mechanisms. In vitro, the cell growth and repairing ability were assessed by CCK-8 assay and wound healing assay. The cell migration and invasion activity was evaluated by Tanswell assay. In vivo, PANC-1 cell tumor-bearing mice were treated with different concentrations of EA. We found that EA significantly inhibited cell growth, cell repairing activity, and cell migration and invasion in a dose-dependent manner. Treatment of PANC-1 xenografted mice with EA resulted in significant inhibition in tumor growth and prolong mice survival rate. Furthermore, flow cytometric analysis showed that EA increased the percentage of cells in the G1 phase of cell cycle. Western blot analysis revealed that EA inhibited the expression of COX-2 and NF-κB. In addition, EA reversed epithelial to mesenchymal transition by up-regulating E-cadherin and down-regulating Vimentin. In summary, the present study demonstrated that EA inhibited cell growth, cell repairing activity, cell migration and invasion in a dose-dependent manner. EA also effectivelyinhibit human pancreatic cancer growth in mice. The anti-tumor effect of EA might be related to cell cycle arrest, down-regulating the expression of COX-2 and NF-κB, reversing epithelial to mesenchymal transition by up-regulating E-cadherin and down-regulating Vimentin. Our findings suggest that the use of EA would be beneficial for the management of pancreatic cancer.

Oncotarget. 2017 Jan 25. Epub 2017 Jan 25. PMID: 28135203


Caffeic acid and caffeic acid phenethyl ester Induction of cell cycle arrest and apoptotic response of head and neck squamous carcinoma cells.

Natural polyphenols have been observed to possess antiproliferative properties. The effects, including apoptotic potential of bioactive phenolic compounds, caffeic acid (CA) and its derivative caffeic acid phenethyl ester (CAPE), on cell proliferation and apoptosis in human head and neck squamous carcinoma cells (HNSCC) line (Detroit 562) were investigated and compared. Cancer cells apoptosis rates and cell cycle arrests were analysed by flow cytometry. Exposure to CA and CAPE was found to result in a dose-dependent decrease in the viability of Detroit 562 cells at different levels. CA/CAPE treatment did significantly affect the viability of Detroit 562 cells (MTT results). CAPE-mediated loss of viability occurred at lower doses and was more pronounced, with the concentrations which inhibit the growth of cells by 50% estimated at 201.43 μM (CA) and 83.25 μM (CAPE). Dead Cell Assay with Annexin V labelling demonstrated that CA and CAPE treatment of Detroit 562 cells resulted in an induction of apoptosis at 50 μM and 100 μM doses. The rise of mainly late apoptosis was observed for 100 μM dose and CA/CAPE treatment didaffect the distribution of cells in G0/G1 phase. A combination of different phenolic compounds, potentially with chemotherapeutics, could be considered as an anticancer drug.

Evid Based Complement Alternat Med. 2017 ;2017:6793456. Epub 2017 Jan 12. PMID: 28167973


Pomegranate has demonstrated anti-proliferative, anti-metastatic and anti-invasive effects on various cancer cell lines.

Cancer is a pathological condition where excessive and abnormal cell growth leads to widespread invasion within the body to affect various organ functions. It is known that chemotherapeutic agents are themselves possible candidate of cancer generation as they can kill normal cells. So, therapeutic approach for cancer treatment and prevention is weighed in terms of benefit to risk ratio. Nowadays, there is an immense interest for the search herbal formulation with cancer preventive effect because of the problems, generated with existing chemotherapeutic regimens. Research interest in fruits rich in polyphenols is increasing because of their anticancer potential. In this review, we highlight the potential health benefits of pomegranate (Punica granatum) fruit and the underlying mechanism of its inhibition of cancer progression. Pomegranate has demonstrated anti-proliferative, anti-metastatic and anti-invasive effects on various cancer cell line in vitro as well as in vivo animal model or human clinical trial. Although several clinical trials are in progress for identifying the pomegranate as a candidate for various cancer treatment. It is necessary to replicate and validate its therapeutic efficacy by multiple clinical studies in order to formulate pomegranate products as an integral part of the dietary and pharmacological intervention in anticancer therapy. Copyright© 2017 John Wiley&Sons, Ltd.

Phytother Res. 2017 Feb 10. Epub 2017 Feb 10. PMID: 28185340


Ellagic acid can be considered as a potent agent that decreases cell proliferation.

OBJECTIVE: One of the most common malignancies among men is prostate cancer. Ellagic acid (EA), a polyphenol antioxidant, has many pharmacological actions, especially anticancer effects. The purpose of this study was to evaluate the effect of EA treatment on interleukin-6 (IL-6) gene expression, cell viability, IL-6 secretion, phosphorylated STAT3, ERK, and AKT cellular signaling proteins in human prostate cancer cells (PC3).MATERIALS AND METHODS: The cytotoxic effects of the EA (0-100µM) on PC3 cells were determined by 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide assay. IL-6 gene expression was down, using real-time quantitative polymerase chain reaction. The cellular concentration of phosphorylated ERK1/2, AKT, and STAT3 signaling pathways was assessed by Western blotting technic.RESULTS: EA treatment of PC3 cells resulted in a reduction of cell viability and phosphorylated STAT3, ERK, and AKT signaling proteins after 72 h in a dose-dependent manner. IL-6 gene expression and IL-6 levels significantly increased (P

J Cancer Res Ther. 2016 Oct-Dec;12(4):1266-1271. PMID: 28169238


Grape seed proanthocyanidins, honokiol and EGCG appear to be promising bioactive phytochemicals for the management of head and neck cancer.

Despite the development of more advanced medical therapies, cancer management remains a problem. Head and neck squamous cell carcinoma (HNSCC) is a particularly challenging malignancy and requires more effective treatment strategies and a reduction in the debilitating morbidities associated with the therapies. Phytochemicals have long been used in ancient systems of medicine, and non-toxic phytochemicals are being considered as new options for the effective management of cancer. Here, we discuss the growth inhibitory and anti-cell migratory actions of proanthocyanidins from grape seeds (GSPs), polyphenols in green tea and honokiol, derived from the Magnolia species. Studies of these phytochemicals using human HNSCC cell lines from different sub-sites have demonstrated significant protective effects against HNSCC in both in vitro and in vivo models. Treatment of human HNSCC cell lines with GSPs, (-)-epigallocatechin-3-gallate (EGCG), a polyphenolic component of green tea or honokiol reduced cell viability and induced apoptosis. These effects have been associated with inhibitory effects of the phytochemicals on the epidermal growth factor receptor (EGFR), and cell cycle regulatory proteins, as well as other major tumor-associated pathways. Similarly, the cell migration capacity of HNSCC cell lines was inhibited. Thus, GSPs, honokiol and EGCG appear to be promising bioactive phytochemicals for the management of head and neck cancer.

Molecules. 2016 Nov 24 ;21(12). Epub 2016 Nov 24. PMID: 27886147


Curcumin exerts anticancer effects and induces apoptosis in p53 mutated COLO 320DM human colon adenocarcinoma cells.

Curcumin, a natural polyphenolic compound and it is isolated from the rhizome of Curcuma longa, have been reported to possess anticancer effect against stage I and II colon cancer. However, the effect of curcumin on colon cancer at Dukes' type C metastatic stage III remains still unclear. In the present study, we have investigated the anticancer effects of curcumin on p53 mutated COLO 320DM human colon adenocarcinoma cells derived from Dukes' type C metastatic stage. The cellular viability and proliferation were assessed by trypan blue exclusion assay and MTT assay, respectively. The cytotoxicity effect was examined by lactate dehydrogenase (LDH) cytotoxicity assay. Apoptosis was analyzed by DNA fragmentation analysis, Hoechst and propidium iodide double fluorescent staining and confocal microscopy analysis. Cell cycle distribution was performed by flow cytometry analysis. Here we have observed that curcumin treatment significantly inhibited the cellular viability and proliferation potential of p53 mutated COLO 320DM cells in a dose- and time-dependent manner. In addition, curcumin treatment showed no cytotoxic effects to the COLO 320DM cells. DNA fragmentation analysis, Hoechst and propidium iodide double fluorescent staining and confocal microscopy analysis revealed that curcumin treatment induced apoptosis in COLO 320DM cells. Furthermore, curcumin caused cell cycle arrest at the G1 phase, decreased the cell population in the S phase and induced apoptosis in COLO 320DM colon adenocarcinoma cells. Together, these data suggest that curcumin exerts anticancer effects and induces apoptosis in p53 mutated COLO 320DM human colon adenocarcinoma cells derived from Dukes' type C metastatic stage.

Biomed Pharmacother. 2017 Feb ;86:373-380. Epub 2016 Dec 21. PMID: 28011386


Curcumin exposure reduced BPA-induced apoptosis evasion and rapid growth kinetics in all cell lines to varying degrees.

Widespread distribution of bisphenol-A (BPA) complicates epidemiological studies of possible carcinogenic effects on the breast because there are few unexposed controls. To address this challenge, we previously developed non-cancerous human high-risk donor breast epithelial cell (HRBEC) cultures, wherein BPA exposure could be controlled experimentally. BPA consistently induced activation of the mammalian target of rapamycin (mTOR) pathway--accompanied by dose-dependent evasion of apoptosis and increased proliferation--in HRBECs from multiple donors. Here, we demonstrate key molecular changes underlying BPA-induced cellular reprogramming. In 3/3 BPA-exposed HRBEC cell lines, and in T47D breast cancer cells, proapoptotic negative regulators of the cell cycle (p53, p21(WAF1) and BAX) were markedly reduced, with concomitant increases in proliferation-initiating gene products (proliferating cell nuclear antigen, cyclins, CDKs and phosphorylated pRb). However, simultaneous exposure to BPA and the polyphenol, curcumin, partially or fully reduced the spectrum of effects associated with BPA alone, including mTOR pathway proteins (AKT1, RPS6, pRPS6 and 4EBP1). BPA exposure induced an increase in the ERα (Estrogen Receptor): ERβ ratio--an effect also reversed by curcumin (analysis of variance, P

Carcinogenesis. 2013 Mar ;34(3):703-12. Epub 2012 Dec 7. PMID: 23222814


H. rosa-sinesis flower extract contains compounds that inhibit melanoma cell growth.

Skin cancer is extremely common, and melanoma causes about 80% of skin cancer deaths. In fact, melanoma kills over 50 thousand people around the world each year, and these numbers are rising. Clearly, standard treatments are not effectively treating melanoma, and alternative therapies are needed to address this problem. Hibiscus tea has been noted to have medicinal properties, including anticancer effects. Extracts from Hibiscus have been shown to inhibit the growth of a variety of cancer cells. In particular, recent studies found that polyphenols extracted from Hibiscus sabdariffa by organic solvents can inhibit melanoma cell growth. However, effects of aqueous extracts from Hibiscus rosa-sinesis flowers, which are commonly used to make traditional medicinal beverages, have not been examined on melanoma cells. Here, we report that aqueous H. rosa-sinesis flower extract contains compounds that inhibit melanoma cell growth in a dose dependent manner at concentrations that did not affect the growth of nontransformed cells. In addition, these extracts contain low molecular weight growth inhibitory compounds below 3 kD in size that combine with larger compounds to more effectively inhibit melanoma cell growth. Future work should identify these compounds, and evaluate their potential to prevent and treat melanoma and other cancers.

J Tradit Complement Med. 2017 Jan ;7(1):45-49. Epub 2016 Feb 23. PMID: 28053887


Carvacrol could be a novel and strong anticancer agent against the human gastric adenocarcinoma.

Gastric cancer (GC) is the most common cause of morbidity and mortality because of cancer. Medicinal plants containing polyphenolic compounds have gained importance in anticancer treatment. In this context, carvacrol is a main component of many plants in the family Lamiaceae that are frequently used in folk medicine and a good candidate to investigate for GC treatment. The present study aimed to explore the cytotoxic, genotoxic, apoptotic, and reactive oxygen species (ROS)-generating effects of carvacrol on gastric adenocarcinoma in vitro. For these purposes, human gastric adenocarcinoma (AGS) cells were used and analyzed after 24 h of exposure to carvacrol with different concentrations. The cytotoxicity, ROS generation, glutathione (GSH) level, and genotoxicity were investigated by the ATP cell viability assay, 2',7'-dichlorodihydrofluorescein-diacetate assay, GSH/GSSG-Glo assay, and comet assay, respectively. Apoptosis induction was detected by acridine orange/ethidium bromide staining and western blotting at below the half-maximal growth inhibitory concentration value. Carvacrol showed cytotoxic, genotoxic, apoptotic, ROS generating, and GSH-reducing effects on AGS cells in a dose-dependent manner. There was a close negative relationship between cell viability and ROS level. Carvacrol inhibited the proliferation of AGS cells, suggesting that it could be a novel and strong anticancer agent against the human gastric adenocarcinoma. These results support the interest of natural diet components in the development of therapeutic products for diseases.

Anticancer Drugs. 2017 Feb 27. Epub 2017 Feb 27. PMID: 28244942


This evaluated the antioxidant and antiproliferative effects of polyphenolic extracts obtained from old twelve varieties of endemic bean.

Beans are important dietary components with versatile health benefits. We analysed the extracts of twelve ecotypes of Phaseolus vulgaris in order to determine their phenolic profiles, antioxidant activity, and the in vitro antiproliferative activity. Ultra-performance liquid chromatography with diode array detector (UPLC-DAD) admitted us to detect and quantify some known polyphenols, such as gallic acid, chlorogenic acid, epicatechin, myricetin, formononetin, caffeic acid, and kaempferol. The antioxidant activity (AA) ranged from 1.568± 0.041 to 66.572 ± 3.197 mg necessary to inhibit the activity of the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical by 50% (EC50). The extracts, except those obtained from the nonpigmented samples, were capable of inhibiting the proliferation of the human epithelial colorectal adenocarcinoma (Caco-2) cells, human breast cancer cells MCF-7, and A549 NSCLC cell line. Cultivars differed in composition and concentration of polyphenols including anthocyanins; cooking affected the antioxidant activity only marginally. Qualitative and quantitative differences in phenolic composition between the groups of beans influenced the biological activities; on the other hand, we did not find significant differences on the biological activities within the same variety, before and after cooking.

Oxid Med Cell Longev. 2016 ;2016:1398298. Epub 2016 Dec 25. PMID: 28105248


Phenolic fractions from Muscadine grape "Noble" pomace can inhibit breast cancer cell MDA-MB-231 better than those from European grape.

Tons of grape pomace which still contained a rich amount of plant polyphenols, is discarded after winemaking. Plant polyphenols have multi-functional activities for human body. In this study, polyphenols of pomaces from Muscadinia rotundifolia"Noble"and Vitis vinifera"Cabernet Sauvignon"were extracted and fractionated, and then they were analyzed with LC-MS and the inhibitory effects on breast cancer cells were compared. The inhibition on MDA-MB-231 cells of fractions from"Noble"was further evaluated. The results showed that polyphenols from 2 grape pomaces could be separated into 3 fractions, and ellagic acid and/or ellagitannins were only detected in fractions from"Noble"pomace. All 3 fractions from"Noble"pomace inhibited MDA-MB-231 better than MCF-7. But fraction 2 from"Cabernet Sauvignon"inhibited MCF-7 better while fraction 1 and fraction 3 inhibited both 2 cells similarly. Moreover, the fractions from"Noble"pomace rather than"Cabernet Sauvignon"can inhibit MDA-MB-231 better. Finally, fractions from"Noble"pomace can induce S-phase arrest and apoptosis on MDA-MB-231. These findings suggested the extracts from grape pomace especially those from"Noble,"are potential to be utilized as health beneficial products or even anti-breast cancer agents.

J Food Sci. 2017 Mar 22. Epub 2017 Mar 22. PMID: 28329437


Polyphenols of Pinus koraiensis pinecone could be a promising natural antitumor agents.

In this study, an efficient purification method for the polyphenols of Pinus koraiensis pinecone (PPP) has been developed. AB-8 resin was verified to offer good adsorption and desorption ratio for PPP. Response surface methodology (RSM) indicated that the optimized purification parameters for PPP were 1.70 mg GAE/mL phenolic sample concentration, 22.00 mL sample volume, and 63.00% ethanol concentration. Under these conditions, the experimental purity of PPP was 27.93± 0.14% (n = 3), which matched well with the predicted purity of 28.17%. Next, the antiproliferative effects of PPP on seven cancer cell lines, including A375 (human skin melanoma cancer cell line), A549 (human lung cancer cell line), SH-SY5Y (human neuroblastoma cell line), LOVO (human colon cancer stem cell line), MCF-7 (human breast cancer cell line), HeLa (human cervical cancer line), and HT29 (human colon cancer line), were examined by MTT assays. The results indicated that PPP had the highest capacity for inhibiting LOVO cells growth with an EC50 value of 0.317 ± 0.0476 mg/mL. Finally,Ultra-high performance liquid chromatography- tandem mass spectrometry (UPLC-MS) was used to tentatively identify twenty-four peaks in the purified PPP, of which five representative peaks were identified as catechin, methyl quercetin, o-vanillin, luteolin and coronaric acid. Our results demonstratethat Pinus koraiensis pinecone is a readily available source of polyphenols, and the purified PPP could be a promising natural antitumor agent for applications in functional foods.

Molecules. 2015 Jun 5 ;20(6):10450-67. Epub 2015 Jun 5. PMID: 26056816


Recent studies have documented that pharmacological effects of curcumin in lung cancer are also mediated by modulation of several miRNAs.

BACKGROUND: Lung cancer is one of the most common types of cancer worldwide and is characterized by a poor prognosis, related both to late diagnosis and lack of effective treatments. In the last years, microRNAs (miRNAs) have been demonstrated to have an important role in tumor microenvironment and immune regulation. These RNAs can be categorized into tumor-suppressor genes, such as let-7 family and miR-34, and oncogenes such as miR-221 and miR-222. Curcumin is a bioactive polyphenol that is documented to have promising anti-cancer activity, and to be well tolerated in humans.METHODS: The present review aims to gather available evidence on the involvement of mRNAs in the therapeutic effects of curcumin against lung cancer.RESULTS: The anti-cancer properties of curcumin against lung cancer have been shown in both cellular and experimental models and are mediated by modulation of several molecular targets that regulate the expression of transcription factors, inflammatory cytokines, enzymes, growth factors, receptors, adhesion molecules, antiapoptotic proteins, and cell cycle proteins, leading to cell apoptosis, inhibition of cell proliferation and migration, and also chemo- and radio-sensitization of lung cancer cells. Recent studies have documented that pharmacological effects of curcumin in lung cancer are also mediated by modulation of several miRNAs, such as downregulation of oncogenic miR-21 and upregulation of oncosuppressive miR-192-5p and miR-215.CONCLUSION: Further studies are necessary to explore this very promising field and the link between regulation of oncogenic and tumor-suppressive miRNAs and putative anti-cancer properties of curcumin.

Curr Pharm Des. 2017 Jan 9. Epub 2017 Jan 9. PMID: 28067164


Proliferation of hepatic and colon cancer cells, HepG2 and Caco-2, were shown to be sensitive to olive leaf extract.

Olea europaea L. has been widely used as an advantageous rich source of bioactive compounds of high economic value leading to its use in pharmaceutical, cosmetic, and agriculture industries. Ethanolic extracts of olive fruits from three different cultivars (OFE) were studied for their phytochemical contents and were investigated for antioxidant activities and anticancer potential. Major polyphenols detected in these extracts were tyrosol, hydroxytyrosol, oleuropein, rutin, quercetin and glucoside forms of luteolin and apigenin. All these compounds have shown to significantly contribute to the antioxidant activity of OFE, which was evaluated by DPPH and ABTS assays. Proliferation of hepatic and colon cancer cells, HepG2 and Caco-2, were shown to be sensitive to OFE with IC50 less than 1.6mg/ml for all tested extracts. Moreover, flow cytometry analysis showed that OFE induced cell cycle arrest in the S-phase within both HepG2 and Caco-2 cells. This has triggered a cell death mechanism as shown by DNA fragmentation, expression of p53 and phosphorylation level of Akt and Erk proteins. Interestingly, these extracts could be further used as a potential source of natural compounds with both antioxidant and anticancer effects.

Biomed Pharmacother. 2017 Mar 27 ;90:179-186. Epub 2017 Mar 27. PMID: 28360012


New insights into therapeutic activity and anticancer properties of curcumin.

Natural compounds obtained from plants are capable of garnering considerable attention from the scientific community, primarily due to their ability to check and prevent the onset and progress of cancer. These natural compounds are primarily used due to their nontoxic nature and the fewer side effects they cause compared to chemotherapeutic drugs. Furthermore, such natural products perform even better when given as an adjuvant along with traditional chemotherapeutic drugs, thereby enhancing the potential of chemotherapeutics and simultaneously reducing their undesired side effects. Curcumin, a naturally occurring polyphenol compound found in the plant Curcuma longa, is used as an Indian spice. It regulates not only the various pathways of the immune system, cell cycle checkpoints, apoptosis, and antioxidant response but also numerous intracellular targets, including pathways and protein molecules controlling tumor progression. Many recent studies conducted by major research groups around the globe suggest the use of curcumin as a chemopreventive adjuvant molecule to maximize and minimize the desired effects and side effects of chemotherapeutic drugs. However, low bioavailability of a curcumin molecule is the primary challenge encountered in adjuvant therapy. This review explores different therapeutic interactions of curcumin along with its targeted pathways and molecules that are involved in the regulation of onset and progression of different types of cancers, cancer treatment, and the strategies to overcome bioavailability issues and new targets of curcumin in the ever-growing field of cancer.

J Exp Pharmacol. 2017 ;9:31-45. Epub 2017 Mar 31. PMID: 28435333


The results support a role for dietary polyphenols in protecting against benzo[a]pyrene induced carcinogenesis.

While dietary polyphenols are widely recognized for cancer-preventing characteristics, the relative effectiveness and mechanisms of action of different polyphenols is not clear. In the present study, we investigated the protective effects of six different polyphenols against benzo[a]pyrene (B[a]P)-induced oxidative stress and neoplastic transformation in the Bhas 42 cell carcinogenesis assay. All of the polyphenols completely prevented the increased intracellular ROS generation by B[a]P at 12 h, and most inhibited after 3 days. B[a]P increased mitochondrial superoxide generation at 12 h, which was inhibited by the anthocyanins and berberine. B[a]P increasedexpression of genes related to oxidative stress and inflammation (Nrf2, UCP2, and TNF-α) after 24 h. Polyphenols strongly inhibited the increase in TNF-α and also several polyphenols inhibited the increase in UCP2. At 21 days after 72 h treatment, B[a]P produced a large increase in the number of neoplastic colonies. This transformation was inhibited by most polyphenols, and strongly by resveratrol. In summary, all tested polyphenols were able to inhibit B[a]P-induced increases in markers of oxidative stress and inflammation, and to inhibit cellular transformation, with resveratrol being notable for the strongest preventive effect on cell transformation. The results support a role for dietary polyphenols in protecting against B[a]P-induced carcinogenesis.

Food Chem Toxicol. 2017 May 19. Epub 2017 May 19. PMID: 28533128


Rosmarinus officinalis L. extracts markedly inhibited the proliferation of two tested cancer cells.

Rosmarinus officinalis L., a medicinal herb from the labiates family, has been reported to have potential benefit in the treatment and prevention of several diseases. In particular its phenolics have demonstrated protective effects on various types of cancer through several mechanisms. The present study aimed to determine the effects of rosemary phenolic extracts on human cell functions, with particular regard to their anti-proliferative properties in three cell types U937, CaCo-2 and the peripheral blood mononuclear cells (PBMCs). The radical scavenging and Ferric reducing abilities of the extracts have been assessed as well as their cyto-toxicity and effects on cell cycle distribution and apoptosis. About 13 compounds were identified with dominance of rosmarinic acid in the methanolic extract and phenolic diterpens in the ethyl acetate fraction (Carnosol, Carnosic acid and methyl Carnosate). The total polyphenolic content was important in the first extract with 2.589± 0.005 g/100 g in gallic acid equivalent compared to 0.763 ± 0.005 g/100 g. The methanolic fraction displayed higher antioxidant activity (DPPHIC50: 0.510 mg/mL and FRAP: 1.714 ± 0.068 mmol Fe(2+)/g) while ethyl acetate showed pronounced antiproliferative effects (IC50: 14.85 ± 0.20µg/mL and 14.95 ± 2.32 µg/mL respectively for U937 and CaCo-2 cells). The anti-proliferative effect was associated with a cell cycle arrest in S phase for U937 (62% of the population at 5 µg/mL) with a concomitant decrease in G1 and G2/M phases. Tested extracts displayed in addition early apoptotic effectsin U937 and late apoptosis in CaCo-2 cells. The obtained data indicate that the identified phenolics are at least partially responsible for the observed cytotoxicity.

Iran J Pharm Res. 2017 ;16(1):315-327. PMID: 28496485

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