151
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Peng L, Khan N, Afaq F, Ye C, Mukhtar H. In vitro and in vivo effects of water extract of white cocoa tea (Camellia ptilophylla) against human prostate cancer. Pharm Res 2010; 27:1128-37. [PMID: 20224992 DOI: 10.1007/s11095-010-0052-7] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2009] [Accepted: 01/05/2010] [Indexed: 11/24/2022]
Abstract
PURPOSE We evaluated the chemotherapeutic effect of water extract of white cocoa tea (WCTE) against human prostate cancer (PCa) in vitro and in vivo. METHODS Cell viability and cell cycle distribution were determined by MTT assay and flow cytometry, respectively. Western blotting was performed to determine changes in levels of various proteins. Effect of WCTE was determined in athymic nude mice implanted with PC-3 cells. RESULTS Treatment with WCTE (100-150 microg/ml) inhibited cell proliferation, which correlated with G2/M phase arrest in PC-3 cells. WCTE treatment to PC-3 cells resulted in (1) induction of WAF1/p21 and KIP1/p27, (2) decrease in cyclins D1, D2 and E, (3) decrease in cyclin-dependent kinase (cdk) 2, 4 and 6, (4) induction of Bax and down-regulation of Bcl-2, (5) decrease in procaspase-3, -8, (6) inhibition of nuclear translocation and phosphorylation of NF-kappaB and activation of IKKalpha, and (7) inhibition of phosphorylation and degradation of IkappaBalpha. Oral administration of WCTE (0.1 and 0.2%, wt/vol) to athymic nude mice resulted in greater than 50% inhibition of tumor growth. There was a decrease in expressions of cyclin D1, Bcl-2 and p-NF-kappaB and an increase in WAF1/p21 and Bax in tumor tissues of mice. CONCLUSION WCTE can be a useful chemotherapeutic agent against human PCa.
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Affiliation(s)
- Li Peng
- School of Life Science, Sun Yat-sen University, Guangzhou 510275, China
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152
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Abstract
Accumulating data clearly indicate that induction of apoptosis is an important event for chemoprevention of cancer by naturally occurring dietary agents. In mammalian cells, apoptosis has been divided into two major pathways: the extrinsic pathway, activated by pro-apoptotic receptor signals at the cellular surface; and the intrinsic pathway, which involves the disruption of mitochondrial membrane integrity. This process is strictly controlled in response to integrity of pro-death signaling and plays critical roles in development, maintenance of homeostasis, and host defense in multicellular organisms. For chemoprevention studies, prostate cancer (PCa) represents an ideal disease due to its long latency, its high incidence, tumor marker availability, and identifiable preneoplastic lesions and risk groups. In this article, we highlight the studies of various apoptosis-inducing dietary compounds for prevention of PCa in vitro in cell culture, in preclinical studies in animals, and in human clinical trials.
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Affiliation(s)
- Naghma Khan
- Department of Dermatology, Medical Sciences Center, University of Wisconsin-Madison, 4385, 1300 University Avenue, Madison, Wisconsin 53706, USA
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153
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Dennis T, Fanous M, Mousa S. Natural products for chemopreventive and adjunctive therapy in oncologic disease. Nutr Cancer 2010; 61:587-97. [PMID: 19838932 DOI: 10.1080/01635580902825530] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Nutritional supplements or complementary and alternative medicines (CAM) are currently being investigated for their use in preventing, inhibiting, and reversing the progression of cancer. Natural agents and their derivatives such as vitamin A, selenium, green tea, resveratrol, aspirin, and probiotics have potential benefits in chemoprevention. There is also growing evidence for the use of natural products as adjunctive therapy alongside conventional cancer treatments. Nutritional supplements expenditures demonstrated greater growth than pharmaceuticals, with approximately 80% of cancer patients using natural products. Current issues with nutritional supplements use in cancer treatment include insufficient or conflicting evidence, poor quality control, potential interactions with chemotherapy, and potential efficacy in relation to changes in certain biomarkers, but long-term implications remain largely unresolved. Continued research is needed to lend credibility to these potentially valuable naturally driven supplements in the prevention and potentially in the treatment of cancer in conjunction with standard pharmaceuticals.
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Affiliation(s)
- Tiffany Dennis
- Albany College of Pharmacy, The Pharmaceutical Research Institute, Albany, New York, USA
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154
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Johnson JJ, Bailey HH, Mukhtar H. Green tea polyphenols for prostate cancer chemoprevention: a translational perspective. PHYTOMEDICINE : INTERNATIONAL JOURNAL OF PHYTOTHERAPY AND PHYTOPHARMACOLOGY 2010; 17:3-13. [PMID: 19959000 PMCID: PMC2789276 DOI: 10.1016/j.phymed.2009.09.011] [Citation(s) in RCA: 120] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2009] [Revised: 08/26/2009] [Accepted: 09/22/2009] [Indexed: 05/28/2023]
Abstract
Every year nearly 200,000 men in the United States are diagnosed with prostate cancer (PCa), and another 29,000 men succumb to the disease. Within certain regions of the world population based studies have identified a possible role for green tea in the prevention of certain cancers, especially PCa. One constituent in particular, epigallocatechin-3-gallate also known as EGCG has been shown in cell culture models to decrease cell viability and promote apoptosis in multiple cancer cell lines including PCa with no effect on non-cancerous cell lines. In addition, animal models have consistently shown that standardized green tea polyphenols when administered in drinking water delay the development and progression of PCa. Altogether, three clinical trials have been performed in PCa patients and suggest that green tea may have a distinct role as a chemopreventive agent. This review will present the available data for standardized green tea polyphenols in regard to PCa chemoprevention that will include epidemiological, mechanism based studies, safety, pharmacokinetics, and applicable clinical trials. The data that has been collected so far suggests that green tea may be a promising agent for PCa chemoprevention and further clinical trials of participants at risk of PCa or early stage PCa are warranted.
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Affiliation(s)
- J J Johnson
- University of Wisconsin School of Pharmacy, Division of Pharmacy Practice, 1031 Rennebohm Hall, Madison, WI, USA.
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155
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Okada N, Tanabe H, Tazoe H, Ishigami Y, Fukutomi R, Yasui K, Isemura M. Differentiation-associated alteration in sensitivity to apoptosis induced by (-)-epigallocatechin-3-O-gallate in HL-60 cells. ACTA ACUST UNITED AC 2009; 30:201-6. [PMID: 19729850 DOI: 10.2220/biomedres.30.201] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Green tea and its constituent (-)-epigallocatechin-3-O-gallate (EGCG) are known to have apoptosis-inducing activity on tumor cells including human leukemia HL-60 cells, providing an explanation for their anti-cancer effects. In the present study, we compared the sensitivity of undifferentiated cells and differentiated HL-60 cells with normal-like phenotypic characters. HL-60 cells treated with three differentiating agents were found to be resistant to EGCG-mediated apoptosis as compared with undifferentiated cells. Gene and protein expression of 67 kDa laminin receptor was down-regulated in differentiated HL-60 cells, suggesting its contribution to the difference in sensitivity in view of the fact that the receptor is a target of EGCG's action to induce apoptosis. The finding supports the view that EGCG induces apoptosis preferentially in cancer cells as compared with normal counterparts.
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156
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Morey Kinney SR, Zhang W, Pascual M, Greally JM, Gillard BM, Karasik E, Foster BA, Karpf AR. Lack of evidence for green tea polyphenols as DNA methylation inhibitors in murine prostate. Cancer Prev Res (Phila) 2009; 2:1065-75. [PMID: 19934341 DOI: 10.1158/1940-6207.capr-09-0010] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Green tea polyphenols (GTP) have been reported to inhibit DNA methylation in cultured cells. Here, we tested whether oral consumption of GTPs affects normal or cancer-specific DNA methylation in vivo, using mice. Wild-type (WT) and transgenic adenocarcinoma of mouse prostate (TRAMP) mice were given 0.3% GTPs in drinking water beginning at 4 weeks of age. To monitor DNA methylation, we measured 5-methyl-deoxycytidine (5mdC) levels, methylation of the B1 repetitive element, and methylation of the Mage-a8 gene. Each of these parameters were unchanged in prostate, gut, and liver from WT mice at both 12 and 24 weeks of age, with the single exception of a decrease of 5mdC in the liver at 12 weeks. In GTP-treated TRAMP mice, 5mdC levels and the methylation status of four loci hypermethylated during tumor progression were unaltered in TRAMP prostates at 12 or 24 weeks. Quite surprisingly, GTP treatment did not inhibit tumor progression in TRAMP mice, although known pharmacodynamic markers of GTPs were altered in both WT and TRAMP prostates. We also administered 0.1%, 0.3%, or 0.6% GTPs to TRAMP mice for 12 weeks and measured 5mdC levels and methylation of B1 and Mage-a8 in prostate, gut, and liver tissues. No dose-dependent alterations in DNA methylation status were observed. Genome-wide DNA methylation profiling using the HpaII tiny fragment enrichment by ligation-mediated PCR assay also revealed no significant hypomethylating effect of GTP. These data indicate that oral administration of GTPs does not affect normal or cancer-specific DNA methylation in the murine prostate.
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Affiliation(s)
- Shannon R Morey Kinney
- Department of Pharmacology and Therapeutics, Roswell Park Cancer Institute, Buffalo, New York, USA
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157
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Fan X, Mustafi D, Zamora M, River JN, Foxley S, Karczmar GS. Can DCEMRI assess the effect of green tea on the angiogenic properties of rodent prostate tumors? Phys Med 2009; 26:111-6. [PMID: 19648041 DOI: 10.1016/j.ejmp.2009.07.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/08/2009] [Revised: 05/31/2009] [Accepted: 07/06/2009] [Indexed: 11/30/2022] Open
Abstract
The purpose of this research was to test whether dynamic contrast enhanced MRI could assess the effect of green tea on the angiogenic properties of transplanted rodent tumors. Copenhagen rats bearing AT6.1 prostate tumors inoculated in the hind limbs were randomly assigned to cages in which they were allowed to only drink either plain water (control group) or water containing green tea extract (treated group). Assignments were made after a baseline MRI experiment (week 0) was performed on each rat at 4.7T. All the rats were subsequently imaged at day 7 (week 1) and day 14 (week 2) to follow tumor growth and vascular development. The two-compartment pharmacokinetic model was used to analyze the dynamic contrast Gd-DTPA enhanced MRI data on a pixel-by-pixel basis over the tumor area to obtain the volume transfer constant (K(trans)) and extravascular extracellular space (v(e)). An identity Chi-squared test showed that the distributions of averaged histograms (n=6) of K(trans) and v(e) were significantly different from week 0 to both weeks 1 and 2 (p<0.001) in both the control and the treated rats due to increasing areas of tumor necrosis. However, the tumor growth rate was statistically indistinguishable between control and treated rats. There was no significant difference in the distributions of K(trans) and v(e) between control and treated rats. The results showed that no effects of green tea on tumor micro-vasculature were measurable by dynamic Gd-DTPA enhanced MRI.
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Affiliation(s)
- Xiaobing Fan
- Department of Radiology, The University of Chicago, Chicago, IL 60637, USA
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158
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Cai H, Sale S, Schmid R, Britton RG, Brown K, Steward WP, Gescher AJ. Flavones as colorectal cancer chemopreventive agents--phenol-o-methylation enhances efficacy. Cancer Prev Res (Phila) 2009; 2:743-50. [PMID: 19638489 DOI: 10.1158/1940-6207.capr-09-0081] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Flavonoids occur ubiquitously in plants, and some possess preclinical cancer chemopreventive activity. Little is known about molecular features that mediate chemopreventive efficacy of flavonoids. Here, three related flavones, apigenin (4',5,7-trihydroxyflavone), tricin (4',5,7-trihydroxy-3',5'-dimethoxyflavone), and 3',4',5',5,7-pentamethoxyflavone (PMF), were compared in terms of their effects on (a) adenoma development in Apc(Min) mice, a model of human gastrointestinal malignancies; (b) growth of APC10.1 mouse adenoma cells in vitro; and (c) prostaglandin E-2 generation in HCA-7 human-derived colorectal cancer cells in vitro. Life-long consumption of PMF with the diet at 0.2% reduced Apc(Min) mouse adenoma number and burden by 43% and 61%, respectively, whereas apigenin was inactive. Tricin has previously shown activity in this model. IC50 values for murine adenoma cell growth inhibition by PMF, tricin, and apigenin were 6, 13, and 18 micromol/L, respectively. In Apc(Min) mice that received flavones (0.2%) for 4 weeks, adenoma cell proliferation as reflected by Ki-67 staining was reduced by PMF and tricin, but not by apigenin. On incubation with HCA-7 cells for 6 hours, PMF reduced prostaglandin E-2 generation with an IC50 of 0.8 micromol/L, a fraction of the respective values reported for tricin or apigenin. In silico PMF docked into the cyclooxygenase active site with greater affinity than tricin or apigenin. The results suggest that the rank order of cancer chemopreventive efficacy in Apc(Min) mice is PMF > tricin > apigenin, supporting the notion that the presence of O-methyl in the flavone molecular scaffold promotes gastrointestinal cancer chemopreventive efficacy.
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Affiliation(s)
- Hong Cai
- Department of Cancer Studies and Molecular Medicine, University of Leicester, Robert Kilpatrick Clinical Sciences Building, Leicester LE2 7LX, United Kingdom
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159
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Ahmad I, Sansom OJ, Leung HY. The role of murine models of prostate cancer in drug target discovery and validation. Expert Opin Drug Discov 2009; 4:879-88. [DOI: 10.1517/17460440903049308] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
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160
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Shamim U, Hanif S, Ullah MF, Azmi AS, Bhat SH, Hadi SM. Plant polyphenols mobilize nuclear copper in human peripheral lymphocytes leading to oxidatively generated DNA breakage: Implications for an anticancer mechanism. Free Radic Res 2009; 42:764-72. [DOI: 10.1080/10715760802302251] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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161
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Adhami VM, Mukhtar H. Polyphenols from green tea and pomegranate for prevention of prostate cancer. Free Radic Res 2009; 40:1095-104. [PMID: 17015254 DOI: 10.1080/10715760600796498] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Prostate cancer (PCa) is the most common non-cutaneous cancer diagnosed in North America with similar trends in many Western countries. Geographic, epidemiological and laboratory studies suggest a role for dietary constituents in the etiology as well as prevention of PCa. The rising incidence of PCa in several countries appears to be coincidental with adoption of western lifestyle. Increase in the incidence of PCa has also been found in Asian populations migrating to the west. These facts give numerous leads to explore testable PCa prevention strategies. There is growing evidence in support of use of dietary ingredients in prevention and treatment of PCa. While substantial data exists in favor of use of polyphenols from tea as PCa chemopreventive agent, interest in anti-cancer properties of polyphenols from pomegranate has recently emerged. This review summarizes current literature on the effects of polyphenols from green tea and pomegranate against PCa.
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Affiliation(s)
- Vaqar M Adhami
- Department of Dermatology, University of Wisconsin-Madison, Madison, WI 53706, USA
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162
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Marine Two-Headed Sphingolipid-Like Compound Rhizochalin Inhibits EGF-Induced Transformation of JB6 P+ Cl41 Cells. Lipids 2009; 44:777-85. [DOI: 10.1007/s11745-009-3322-6] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2009] [Accepted: 06/15/2009] [Indexed: 10/20/2022]
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163
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Benitez DA, Hermoso MA, Pozo-Guisado E, Fernández-Salguero PM, Castellón EA. Regulation of cell survival by resveratrol involves inhibition of NF kappa B-regulated gene expression in prostate cancer cells. Prostate 2009; 69:1045-54. [PMID: 19301309 DOI: 10.1002/pros.20953] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
BACKGROUND Polyphenols have been proposed as antitumoral agents. We have shown that resveratrol (RES) induced cell cycle arrest and promoted apoptosis in prostate cancer cells by inhibition of the PI3K pathway. The RES effects on NF kappaB activity in LNCaP cells (inducible NF kappaB), and PC-3 cells (constitutive NF kappaB) are reported. METHODS Cells were treated with 1-150 microM of RES during 36 hr. NF kappaB subcellular localization was analyzed by western blot and immunofluorescence. I kappaB alpha was evaluated by immunoprecipitation followed by Western blot. Specific DNA binding of NF kappaB was determined by EMSA assays and NF kappaB-mediated transcriptional activity by transient transfection with a luciferase gene reporter system. RESULTS RES induced a dose-dependent cytoplasmic retention of NF kappaB mediated by I kappaB alpha in PC-3 cells but not in LNCaP. RES-induced inhibition of NF kappaB specific binding to DNA was more significant in PC-3 cells. NF kappaB-mediated transcriptional activity induced by EGF and TNFalpha were inhibited by RES in both cell lines. LY294002 mimicked RES effects on NF kappaB activity. CONCLUSION Antiproliferative and apoptotic effects of RES on human prostate cancer cells may be mediated by the inhibition of NF kappaB activity. This mechanism seems to be associated to RES-induced PI3K inhibition. RES could have therapeutic potential for prostate cancer treatment.
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Affiliation(s)
- Dixan A Benitez
- Laboratorio de Andrología Celular y Molecular, PDFB, Universidad de Chile, Santiago, Chile
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164
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McCarthy S, Caporali A, Enkemann S, Scaltriti M, Eschrich S, Davalli P, Corti A, Lee A, Sung J, Yeatman TJ, Bettuzzi S. Green tea catechins suppress the DNA synthesis marker MCM7 in the TRAMP model of prostate cancer. Mol Oncol 2009; 1:196-204. [PMID: 18521193 DOI: 10.1016/j.molonc.2007.05.007] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
Green tea catechins (GTCs) exert chemopreventive effects in many cancer models. Several studies implicate the DNA synthesis marker minichromosome maintenance protein 7 (MCM7) in prostate cancer progression, growth and invasion; representing a novel therapeutic target. In this study, we investigated the effect of GTCs on MCM7 expression in the transgenic adenocarcinoma mouse prostate model (TRAMP). DNA microarray, immunohistochemistry and western blot analysis showed that GTCs significantly suppressed MCM7 in the TRAMP mice treated with GTCs. Our study indicates that the cellular DNA replication factor MCM7 is involved in prostate cancer (CaP) and MCM7 gene expression was reduced by GTCs. Together, these results suggest a possible role of GTCs in CaP chemoprevention in which MCM7 plays a critical role.
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Affiliation(s)
- Susan McCarthy
- Department of Interdisciplinary Oncology, H. Lee Moffitt Cancer Center and Research Institute, University of South Florida, Tampa, Florida, USA
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165
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Pandey M, Gupta S. Green tea and prostate cancer: from bench to clinic. Front Biosci (Elite Ed) 2009; 1:13-25. [PMID: 19482620 PMCID: PMC2728057 DOI: 10.2741/e2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Green tea, the most popular beverage next to water, is a rich source of tea catechins and has potential to be developed as a chemopreventive agent for prostate cancer. For centuries it has been used in traditional medicine in Far-East countries. Male populations in these countries where large quantities of green tea are consumed on regular basis have the lowest incidence of prostate cancer. In this review, after a description of prostate cancer and several risk factors associated with the disease, we evaluated studies reported with green tea or its major constituent, (-)-epigallocatechin-3-gallate in inhibition of prostate cancer. This review provides an in-depth overview of various biochemical and signaling pathways affected by green tea in in vivo and in vitro models of prostate cancer. This is followed by a comprehensive discussion of the epidemiological studies and some ongoing clinical trials with green tea catechins. The review concludes with a brief discussion of the future direction and development of clinical trials employing green tea catechins which could be developed for prevention and/or intervention of prostate cancer.
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Affiliation(s)
- Mitali Pandey
- Department of Urology and Nutrition, Case Western Reserve University, Clevelamd, OH 44106
- University Hospitals Case Medical Center, Case Western Reserve University, Cleveland, OH 44106
| | - Sanjay Gupta
- Department of Urology and Nutrition, Case Western Reserve University, Clevelamd, OH 44106
- University Hospitals Case Medical Center, Case Western Reserve University, Cleveland, OH 44106
- Case Comprehensive Cancer Center, Cleveland, Ohio 44106
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166
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Yang CS, Wang X, Lu G, Picinich SC. Cancer prevention by tea: animal studies, molecular mechanisms and human relevance. Nat Rev Cancer 2009; 9:429-39. [PMID: 19472429 PMCID: PMC2829848 DOI: 10.1038/nrc2641] [Citation(s) in RCA: 801] [Impact Index Per Article: 53.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Extracts of tea, especially green tea, and tea polyphenols have been shown to inhibit the formation and development of tumours at different organ sites in animal models. There is considerable evidence that tea polyphenols, in particular (-)-epigallocatechin-3-gallate, inhibit enzyme activities and signal transduction pathways, resulting in the suppression of cell proliferation and enhancement of apoptosis, as well as the inhibition of cell invasion,angiogenesis and metastasis. Here, we review these biological activities and existing data relating tea consumption to human cancer risk in an attempt to understand the potential use of tea for cancer prevention.
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Affiliation(s)
- Chung S Yang
- Susan Lehman Cullman Laboratory of Cancer Research, Department of Chemical Biology, Ernest Mario School of Pharmacy, Rutgers, The State University of New Jersey, 164 Frelinghuysen Road, Piscataway, NJ 08854-8020, USA.
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167
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Dorchies OM, Wagner S, Buetler TM, Ruegg UT. Protection of dystrophic muscle cells with polyphenols from green tea correlates with improved glutathione balance and increased expression of 67LR, a receptor for (-)-epigallocatechin gallate. Biofactors 2009; 35:279-94. [PMID: 19322813 DOI: 10.1002/biof.34] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Duchenne muscular dystrophy (DMD) is a fatal muscle wasting disease caused by the absence of the protein dystrophin. Because oxidative stress contributes to the pathogenesis of DMD, we investigated if a green tea polyphenol blend (GTP) and its major polyphenol (-)-epigallocatechin gallate (EGCg), could protect muscle cell primary cultures from oxidative damage induced by hydrogen peroxide (H(2)O(2)) in the widely used mdx mouse model. On-line fluorimetric measurements using an H(2)O(2)-sensitive probe indicated that GTP and EGCg scavenged peroxide in a concentration-dependent manner. A 48 h exposure to EGCg increased glutathione content but did not alter the expression of proteins involved in membrane stabilization and repair. Pretreatment of dystrophic cultures with GTP or EGCg 48 h before exposure to H(2)O(2) improved cell survival. Normal cultures were protected by GTP but not by EGCg. 67LR, a receptor for EGCg, was seven times more abundant in dystrophic compared with normal cultures. Altogether our results demonstrate that GTP and EGCg protect muscle cells by scavenging H(2)O(2) and by improving the glutathione balance. In addition, the higher levels of 67LR in dystrophic muscle cells compared with normal ones likely contribute to EGCg-mediated survival.
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Affiliation(s)
- Olivier M Dorchies
- Laboratory of Pharmacology, Geneva-Lausanne School of Pharmaceutical Sciences, University of Geneva, Geneva, Switzerland
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168
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Wang L, Bonorden MJL, Li GX, Lee HJ, Hu H, Zhang Y, Liao JD, Cleary MP, Lü J. Methyl-selenium compounds inhibit prostate carcinogenesis in the transgenic adenocarcinoma of mouse prostate model with survival benefit. Cancer Prev Res (Phila) 2009; 2:484-95. [PMID: 19401524 DOI: 10.1158/1940-6207.capr-08-0173] [Citation(s) in RCA: 96] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Chemoprevention of prostate cancer by second-generation selenium compounds in reference to selenomethionine holds strong promise to deal with the disease at the root. Here we used the transgenic adenocarcinoma mouse prostate (TRAMP) model to establish the efficacy of methylseleninic acid (MSeA) and methylselenocysteine (MSeC) against prostate carcinogenesis and to characterize potential mechanisms. Eight-week-old male TRAMP mice (C57B/6 background) were given a daily oral dose of water, MSeA, or MSeC at 3 mg Se/kg body weight and were euthanized at either 18 or 26 weeks of age. By 18 weeks of age, the genitourinary tract and dorsolateral prostate weights for the MSeA- and MSeC-treated groups were lower than for the control (P < 0.01). At 26 weeks, 4 of 10 control mice had genitourinary weight >2 g, and only 1 of 10 in each of the Se groups did. The efficacy was accompanied by delayed lesion progression, increased apoptosis, and decreased proliferation without appreciable changes of T-antigen expression in the dorsolateral prostate of Se-treated mice and decreased serum insulin-like growth factor I when compared with control mice. In another experiment, giving MSeA to TRAMP mice from 10 or 16 weeks of age increased their survival to 50 weeks of age, and delayed the death due to synaptophysin-positive neuroendocrine carcinomas and synaptophysin-negative prostate lesions and seminal vesicle hypertrophy. Wild-type mice receiving MSeA from 10 weeks did not exhibit decreased body weight or genitourinary weight or increased serum alanine aminotransferase compared with the control mice. Therefore, these selenium compounds may effectively inhibit this model of prostate cancer carcinogenesis.
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Affiliation(s)
- Lei Wang
- Hormel Institute, University of Minnesota, 801 16th Avenue Northeast, Austin, MN 55912, USA
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169
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El Touny LH, Banerjee PP. Identification of a biphasic role for genistein in the regulation of prostate cancer growth and metastasis. Cancer Res 2009; 69:3695-703. [PMID: 19351854 DOI: 10.1158/0008-5472.can-08-2958] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Considered a chemopreventive agent, the ability of genistein to modulate the progression of existing prostate cancer (CaP) is not clear. We show here that the consumption of genistein (250 mg/kg diet) by 12-week-old transgenic adenocarcinoma mouse prostate (TRAMP-FVB) mice harboring prostatic intraepithelial neoplasia lesions until 20 weeks of age induces an aggressive progression of CaP, as evidenced by a 16% increase in the number of well-differentiated and poorly differentiated prostates, coinciding with a 70% incidence of pelvic lymph node (LN) metastases as opposed to 0% and 10% in 0 and 1,000 mg/kg groups, concomitant with elevated osteopontin (OPN) expression in prostates and LNs. Equivalent nanomolar (500 nmol/L) concentrations of genistein recapitulated these effects in human PC3 CaP cells as evidenced by increased proliferation, invasion, and matrix metalloproteinase-9 (MMP-9) activity (approximately 2-fold), accompanied by an up-regulation of OPN expression and secretion, compared with vehicle-treated cells. A pharmacologic dose (50 micromol/L) decreased proliferation, invasion, and MMP-9 activity (>2.0-fold) concomitant with OPN reduction. Upon OPN knockdown by short hairpin RNA, genistein was no longer effective in up-regulating PC3 cell proliferation, invasion, and MMP-9 activation, which were significantly reduced in the absence of OPN, highlighting the requirement for OPN in mediating the effects of genistein. Proliferation, invasion, and OPN levels were also nonsignificantly induced by genistein in the presence of ICI 182,780 or wortmannin, indicating a dependence on phosphatidylinositol 3-kinase and estrogen signaling. Our results suggest the presence of a biphasic regulation of CaP growth and metastasis by genistein, warranting careful examination of the effects of genistein on hormone-dependent cancers in a chemotherapeutic setting.
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Affiliation(s)
- Lara H El Touny
- Department of Biochemistry and Molecular and Cellular Biology, Georgetown University Medical Center, Washington, District of Columbia 20057, USA
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170
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Adhami VM, Siddiqui IA, Sarfaraz S, Khwaja SI, Hafeez BB, Ahmad N, Mukhtar H. Effective prostate cancer chemopreventive intervention with green tea polyphenols in the TRAMP model depends on the stage of the disease. Clin Cancer Res 2009; 15:1947-53. [PMID: 19276266 DOI: 10.1158/1078-0432.ccr-08-2332] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
PURPOSE We have shown previously that oral feeding of green tea polyphenols (GTP) to transgenic adenocarcinoma of the mouse prostate mice in a purely chemopreventive setting significantly inhibits prostate cancer development. To translate this to a human situation, the present study was designed to identify the stage of prostate cancer that is most vulnerable to chemopreventive intervention by GTP. EXPERIMENTAL DESIGN GTP infusion (0.1% in drinking water) to transgenic adenocarcinoma of the mouse prostate was initiated at ages representing different stage of the disease: (a) 6 weeks (group 1, normal prostate), (b) 12 weeks (group 2, prostatic intraepithelial neoplasia), (c) 18 weeks (group 3, well-differentiated adenocarcinoma), and (b) 28 weeks (group 4, moderately differentiated adenocarcinoma). At age 32 weeks, subsets of animals were evaluated by magnetic resonance imaging, ultrasound, and prostate weight and for serum insulin-like growth factor (IGF)-I/IGF binding protein-3 and IGF signaling. RESULTS Tumor-free survival was extended to 38 weeks (P < 0.001) in group 1, 31 weeks (P < 0.01) in group 2, and 24 weeks (P < 0.05) in group 3 compared with 19 weeks in water-fed controls. Median life expectancy was 68 weeks in group 1, 63 weeks in group 2, 56 weeks in group 3, and 51 weeks in group 4 compared with 42 weeks in the control mice. IGF-I and its downstream targets including phosphatidylinositol 3-kinase, pAkt, and phosphorylated extracellular signal-regulated kinase were significantly inhibited only when intervention was initiated early when prostatic intraepithelial neoplasia lesions were common. CONCLUSIONS Our studies indicate that chemopreventive potential of GTP decreases with advancing stage of the disease and underscore the need to design appropriate chemoprevention clinical trails.
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Affiliation(s)
- Vaqar Mustafa Adhami
- Department of Dermatology, University of Wisconsin-Madison, Madison, Wisconsin, USA
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171
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Hu H, Zhang J, Lee HJ, Kim SH, Lü J. Penta-O-galloyl-beta-D-glucose induces S- and G(1)-cell cycle arrests in prostate cancer cells targeting DNA replication and cyclin D1. Carcinogenesis 2009; 30:818-23. [PMID: 19269999 DOI: 10.1093/carcin/bgp059] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
We have recently shown that penta-1,2,3,4,6-O-galloyl-beta-D-glucose (PGG), a naturally occurring hydrolyzable gallotannin, inhibited the in vivo growth of human androgen-independent p53-mutant DU145 prostate cancer (PCa) xenograft in athymic nude mice without adverse effect on their body weight. We have also shown that PGG induced caspase-mediated apoptosis in the DU145 cells and the androgen-dependent human p53-wild-type LNCaP cells. Here, we investigated the cell cycle effects of PGG in these and other PCa cells. Our data show that treatment with subapoptotic doses of PGG induced S-arrest, whereas higher doses of PGG induced not only S-arrest but also G(1) arrest. We show, for the first time, that irrespective of the p53 functional status of the PCa cell lines, PGG exerted a rapid (within 2 h) and potent inhibition (inhibitory concentration by 50% approximately 6 microM) of 5-bromo-2'-deoxyuridine incorporation into S phase cells. In isolated nuclei, PGG inhibited DNA replicative synthesis with superior efficacy than a known DNA polymerase alpha inhibitor, aphidocolin. In addition to the S-arrest action, we have found a close association of downregulation of cyclin D1 with G(1) arrest induced by PGG. Overexpressing this G(1) cyclin abolished G(1) arrest, but hastened the S-arrest induction by PGG. Together, our data indicate that PGG induced PCa S-arrest probably through DNA replicative blockage and induced G(1) arrest via cyclin D1 downregulation to contribute to anticancer activity. Our data raise the hypothesis that PGG may be a novel inhibitor of DNA polymerases.
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Affiliation(s)
- Hongbo Hu
- Hormel Institute, University of Minnesota, 801 16th Avenue NE, Austin, MN 55912, USA
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172
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Shimizu M, Shirakami Y, Sakai H, Adachi S, Hata K, Hirose Y, Tsurumi H, Tanaka T, Moriwaki H. (-)-Epigallocatechin gallate suppresses azoxymethane-induced colonic premalignant lesions in male C57BL/KsJ-db/db mice. Cancer Prev Res (Phila) 2009; 1:298-304. [PMID: 19138973 DOI: 10.1158/1940-6207.capr-08-0045] [Citation(s) in RCA: 76] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Obesity and diabetes mellitus are risk factors for colon cancer. The activation of the insulin-like growth factor (IGF)/IGF-IR axis plays a critical role in this carcinogenesis. (-)-Epigallocatechin gallate (EGCG), the major constituent of green tea, seems to have both antiobesity and antidiabetic effects. This study examined the effects of EGCG on the development of azoxymethane-induced colonic premalignant lesions in C57BL/KsJ-db/db (db/db) mice, which are obese and develop diabetes mellitus. Male db/db mice were given four weekly s.c. injections of azoxymethane (15 mg/kg body weight) and then they received drinking water containing 0.01% or 0.1% EGCG for 7 weeks. At sacrifice, drinking water with EGCG caused a significant decrease in the number of total aberrant crypt foci, large aberrant crypt foci, and beta-catenin accumulated crypts in these mice, all of which are premalignant lesions of the colon. The colonic mucosa of db/db mice expressed high levels of the IGF-IR, phosphorylated form of IGF-IR (p-IGF-IR), p-GSK-3beta, beta-catenin, cyclooxygenase-2, and cyclin D1 proteins, and EGCG in drinking water caused a marked decrease in the expression of these proteins. Treating these mice with EGCG also caused an increase in the serum level of IGFBP-3 while conversely decreasing the serum levels of IGF-I, insulin, triglyceride, cholesterol, and leptin. EGCG overcomes the activation of the IGF/IGF-IR axis, thereby inhibiting the development of colonic premalignant lesions in an obesity-related colon cancer model, which was also associated with hyperlipidemia, hyperinsulinemia, and hyperleptinemia. EGCG may be, therefore, useful in the chemoprevention or treatment of obesity-related colorectal cancer.
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Affiliation(s)
- Masahito Shimizu
- Department of Medicine, Gifu University Graduate School of Medicine, 1-1 Yanagido, Gifu 501-1194, Japan.
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173
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Bonorden MJL, Rogozina OP, Kluczny CM, Grossmann ME, Grande JP, Lokshin A, Cleary MP. Cross-sectional analysis of intermittent versus chronic caloric restriction in the TRAMP mouse. Prostate 2009; 69:317-26. [PMID: 19016490 DOI: 10.1002/pros.20878] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
BACKGROUND Previously we found that intermittent calorie restriction (ICR) delayed the age of prostate tumor detection and death in TRAMP mice in comparison to chronic calorie restricted (CCR) and ad libitum fed (AL) TRAMP mice. METHODS In the present study the same protocol was used in a cross-sectional experiment whereby mice were either ad libitum fed, intermittently calorie restricted at 50% of the consumption of AL mice for 2 weeks followed by 2 weeks of refeeding matched to AL intake or were pair-fed to the ICR. Both ICR and CCR protocols resulted in a 25% reduction in caloric intake. Mice were enrolled in the study at 7 weeks of age to be euthanized at designated time points in cycles 3, 6, and 9 with mice euthanized at the end of restriction and refeeding. RESULTS At the youngest time point in cycle 3 ICR impacted body weight, fat pad weights and serum factors the most. Additionally, the incidence of detectable prostate cancer pathology was reduced for ICR mice compared to AL and CCR mice. However, by cycle 5 when the mice were 28-30 weeks of age all mice except one ICR mouse had pathologically confirmed prostate cancer. Furthermore, at the two older time points many of the mice assigned to the study did not survive to reach their designated endpoints. CONCLUSIONS Overall these findings are consistent with other studies indicating protective effects of various interventions on the development of prostate cancer in young TRAMP mice.
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175
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The effect of green tea on oxidative damage and tumour formation in Lobund-Wistar rats. Eur J Cancer Prev 2009; 17:489-501. [PMID: 18941371 DOI: 10.1097/cej.0b013e3282f0c04e] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
A number of epidemiological studies suggest that the consumption of green tea reduces the incidence of prostate cancer. As the major catechins present in green tea are potent antioxidants, we hypothesized that genetic and cellular damage induced by oxygen free radicals could be significantly reduced by potent antioxidants in green tea, thus reducing the cumulative genetic and cellular damage with age, and slowing or preventing tumour formation. Long-term administration of a decaffeinated green tea extract to Lobund-Wistar rats for periods up to 26 months almost halved the incidence of primary tumours in the genitourinary tract when compared with an age-matched cohort receiving just water. We observed no inhibition of DNA adduct formation or lipid peroxidation in animals consuming green tea compared with animals consuming deionized water. The decrease in tumour formation was associated with an increase in 8-hydroxy-2'deoxyguanosine and 4-hydroxynonenal content (markers of DNA adduct formation and lipid peroxidation, respectively) in the epithelium of the ventral prostate in aging animals. In addition, there was an increase in 8-hydroxy-2'deoxyguanosine expression, but no change in 4-hydroxynonenal expression in the seminal vesicles of older animals. An age-associated increase in expression of the antioxidant enzymes manganese superoxide dismutase and catalase in the epithelium of the ventral prostate of aging animals was observed. Furthermore, there was also an increase in manganese superoxide dismutase expression, but no change in catalase expression in the seminal vesicles of older animals. These data demonstrate that consumption of green tea decreases the incidence of genitourinary tract tumours in the Lobund-Wistar rat, but has no effect on age-associated DNA adduct formation and lipid peroxidation in the ventral prostate and seminal vesicles of the aging rat.
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176
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Ullah MF, Shamim U, Hanif S, Azmi AS, Hadi SM. Cellular DNA breakage by soy isoflavone genistein and its methylated structural analogue biochanin A. Mol Nutr Food Res 2009; 53:1376-85. [DOI: 10.1002/mnfr.200800547] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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177
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Teichert F, Verschoyle RD, Greaves P, Thorpe JF, Mellon JK, Steward WP, Farmer PB, Gescher AJ, Singh R. Determination of 8-oxo-2'-deoxyguanosine and creatinine in murine and human urine by liquid chromatography/tandem mass spectrometry: application to chemoprevention studies. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2009; 23:258-266. [PMID: 19072863 DOI: 10.1002/rcm.3873] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Urinary 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodG) represents a non-invasive biomarker for oxidative stress and may be useful for monitoring chemotherapeutic and chemopreventive interventions associated with cancer-related alterations in oxidative stress. We describe the development and validation of two separate liquid chromatography/tandem mass spectrometry (LC/MS/MS) selected reaction monitoring (SRM) methods for the determination of 8-oxodG and creatinine in both murine and human urine using stable isotope labelled internal standards. Levels of 8-oxodG were normalised to creatinine. The LC/MS/MS methods were applied to two chemoprevention studies utilising tea polyphenols in humans and TRAMP (TRansgenic Adenocarcinoma of the Mouse Prostate) mice. Patients with benign prostatic hyperplasia received 1 g/day of green tea polyphenols (GTP), 1 g/day of black tea theaflavins (BTT) or no treatment for 4 weeks. TRAMP mice received GTP (0.05% in drinking water) for 4 or 25 weeks. Prostate pathology in TRAMP mice was not affected by GTP. Levels of 8-oxodG were not altered by tea polyphenols in either mice or humans. In TRAMP mice, urinary 8-oxodG levels were elevated with increasing age (p < 0.0001) but not changed by the presence of prostate tumours. In conclusion, the LC/MS/MS SRM methods described here are ideally suited for the accurate determination of 8-oxodG and creatinine in urine samples from both clinical and pre-clinical studies.
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Affiliation(s)
- Friederike Teichert
- Cancer Biomarkers and Prevention Group, Department of Cancer Studies and Molecular Medicine, University of Leicester, UK.
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178
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Park J, Shin DW, Ahn TY. Complementary and alternative medicine in men’s health. JOURNAL OF MENS HEALTH 2008. [DOI: 10.1016/j.jomh.2008.08.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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179
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Chuu CP, Chen RY, Kokontis JM, Hiipakka RA, Liao S. Suppression of androgen receptor signaling and prostate specific antigen expression by (-)-epigallocatechin-3-gallate in different progression stages of LNCaP prostate cancer cells. Cancer Lett 2008; 275:86-92. [PMID: 18977589 DOI: 10.1016/j.canlet.2008.10.001] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2008] [Revised: 10/01/2008] [Accepted: 10/02/2008] [Indexed: 11/25/2022]
Abstract
The green tea polyphenol, (-)-epigallocatechin-3-gallate (EGCG), inhibits the development and progression of prostate cancer in TRAMP mice and in men. We examined the effects of EGCG on LNCaP human prostate cancer sublines 104-S, 104-R1 and R1Ad representing different progression stages of prostate cancer. EGCG suppressed cell proliferation, prostate specific antigen (PSA) expression, and AR transcriptional activity in the different LNCaP sublines. Intraperitoneal administration of EGCG also suppressed the growth of relapsing R1Ad tumors and decreased tumor-derived serum PSA. Effects of EGCG on tumor PSA expression have the potential to affect accurate monitoring of patient tumor burden by serum PSA measurements.
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Affiliation(s)
- Chih-Pin Chuu
- The Ben May Department for Cancer Research, The University of Chicago, 929 East 57th Street, CIS W325F, Chicago, IL 60637, USA.
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180
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Yang CS, Sang S, Lambert JD, Lee MJ. Bioavailability issues in studying the health effects of plant polyphenolic compounds. Mol Nutr Food Res 2008; 52 Suppl 1:S139-51. [PMID: 18551457 DOI: 10.1002/mnfr.200700234] [Citation(s) in RCA: 95] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Polyphenolic compounds are common in the diet and have been suggested to have a number of beneficial health effects including prevention of cancer, cardiovascular disease, diabetes, and others. For some dietary polyphenols, certain benficial effects are suggested by epidemiological studies, some are supported by studies in animal models, and still others are extrapolated from studies in vitro. Because of the relatively poor bioavailability of many of these compounds, the molecular basis of these beneficial effects is not clear. In the present review, we discuss the potential health benefits of dietary polyphenols from the point of view of bioavailability. Tea catechins, curcumin, and proanthocyanidins are used as examples to illustrate some of the problems that need to be resolved. Further research on both the biological activity and bioavailability of dietary polyphenols is needed to properly assess their usefulness for the prevention and treatment of disease.
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Affiliation(s)
- Chung S Yang
- Department of Chemical Biology, Ernest Mario School of Pharmacy, Rutgers, The State University of New Jersey, Piscataway, NJ 08854-8020, USA.
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181
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Siddiqui IA, Shukla Y, Adhami VM, Sarfaraz S, Asim M, Hafeez BB, Mukhtar H. Suppression of NFkappaB and its regulated gene products by oral administration of green tea polyphenols in an autochthonous mouse prostate cancer model. Pharm Res 2008; 25:2135-42. [PMID: 18317887 PMCID: PMC3064432 DOI: 10.1007/s11095-008-9553-z] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2008] [Accepted: 02/01/2008] [Indexed: 10/22/2022]
Abstract
PURPOSE This study examines the role of cell survival/apoptosis related proteins involved in NFkappaB signaling pathways and its associated events in GTP-induced chemoprevention of prostate cancer in TRAMP mice. METHODS Mice were given 0.1% GTP as drinking fluid. Western blot and immunohistochemical analysis performed to examine NFkappaB and its regulated pathway in response to GTP. RESULTS Our data demonstrated increased expression of NFkappaB, IKKalpha, IKKbeta, RANK, NIK and STAT-3 in dorso-lateral prostate of TRAMP mice as a function of age and tumor growth and continuous GTP infusion for 32 weeks resulted in substantial reduction in these proteins. The levels of transcription factor osteopontin, a non-collagenous extracellular matrix protein, were also downregulated. Inhibition of NFkappaB signaling is known to activate apoptotic and inhibit anti-apoptotic proteins. Therefore, we analyzed Bax and Bcl2 levels in the dorsolateral prostate of TRAMP mice fed GTP and observed a shift in balance between Bax and Bcl2 favoring apoptosis. CONCLUSIONS Based on the data we suggest that oral consumption of GTP might inhibit osteopontin and NFkappaB signaling that may contribute to induction of apoptosis observed in GTP fed TRAMP mice.
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Affiliation(s)
- Imtiaz A. Siddiqui
- Department of Dermatology, University of Wisconsin, Madison, Wisconsin 53706, USA
| | - Yogeshwer Shukla
- Proteomics Laboratory, Indian Institute of Toxicology Research, 80 MG Marg, Lucknow, 226001, India
| | - Vaqar M. Adhami
- Department of Dermatology, University of Wisconsin, Madison, Wisconsin 53706, USA
| | - Sami Sarfaraz
- Department of Dermatology, University of Wisconsin, Madison, Wisconsin 53706, USA
| | - Mohammad Asim
- Department of Dermatology, University of Wisconsin, Madison, Wisconsin 53706, USA
| | - Bilal Bin Hafeez
- Department of Dermatology, University of Wisconsin, Madison, Wisconsin 53706, USA
| | - Hasan Mukhtar
- Department of Dermatology, University of Wisconsin, Madison, Wisconsin 53706, USA
- Department of Dermatology, Medical Sciences Center, University of Wisconsin, B-25, 1300 University Avenue, Madison, Wisconsin 53706, USA
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Li J, Li Q, Feng T, Li K. Aqueous extract of Solanum nigrum inhibit growth of cervical carcinoma (U14) via modulating immune response of tumor bearing mice and inducing apoptosis of tumor cells. Fitoterapia 2008; 79:548-56. [PMID: 18687388 DOI: 10.1016/j.fitote.2008.06.010] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2007] [Accepted: 06/06/2008] [Indexed: 01/30/2023]
Abstract
To explore the antitumor activity of aqueous extract of Solanum nigrum (SNL-AE) and its possible mechanism, we examined the effects of SNL-AE on the tumor growth in vivo, the number of CD4+, CD8+ T lymphocyte subsets of peripheral blood in tumor-bearing mice by means of FACScan flow cytometer, the expression of PCNA in U14 cervical carcinoma section by means of immunohistochemistry SP method, the cell cycle of transplanted tumor by means of FACScan flow cytometer and DNA fragmentation by means of agarose gel electrophoresis. Our results showed that SNL-AE could inhibit U14 cervical carcinoma growth and increased the number of CD4+ T lymphocyte subsets as well as the ratio of CD4+/CD8+ T lymphocyte, decreased the number of CD8+ T lymphocyte subsets of tumor-bearing mice and PCNA positive cells. Furthermore, it had the abilities to cause cell cycle arrest in G0/G1 phase and to induce apoptosis of more transplanted tumor cells in a dose-dependent manner. These results indicated that SNL-AE could suppress the cervical carcinoma via modulating immune response of the tumor-bearing mice and causing tumor cell cycle arrest in G0/G1 phase, as well as inducing apoptosis with little toxicity to the animals.
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Affiliation(s)
- Jian Li
- College of Environmental and Chemical Engineering, Yanshan University, Qinhuangdao, Hebei Province 066004, Peoples Republic of China
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183
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Teichert F, Verschoyle RD, Greaves P, Edwards RE, Teahan O, Jones DJL, Wilson ID, Farmer PB, Steward WP, Gant TW, Gescher AJ, Keun HC. Metabolic profiling of transgenic adenocarcinoma of mouse prostate (TRAMP) tissue by 1H-NMR analysis: evidence for unusual phospholipid metabolism. Prostate 2008; 68:1035-47. [PMID: 18459103 DOI: 10.1002/pros.20761] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
BACKGROUND The TRansgenic Adenocarcinoma of the Mouse Prostate (TRAMP) mouse model has frequently been used in preclinical studies with chemotherapeutic/chemopreventive rationales. Here the hypothesis was tested using (1)H-NMR-based metabolic profiling that the TRAMP tumor metabolic phenotype resembles that reported for human prostate cancer. METHODS Aqueous extracts or intact tissues of normal prostate from 8- ("young") or 28-("old") week-old C57BL/6J wild-type mice or of prostate tumor from age-matched TRAMP mice were analyzed by (1)H-NMR. Results were compared with immunohistochemical findings. Expression of choline kinase was studied at the protein and mRNA levels. RESULTS In young TRAMP mice presenting with zonal hyperplasia, the ratio of glycerophosphocholine (GPC) to phosphocholine (PC) was 22% below that in wild-type mice (P < 0.05). In old TRAMP mice with well-defined malignancy, reduced tumor levels of citrate (49%), choline (33%), PC (57%), GPC (66%), and glycerophosphoinositol (61%) were observed relative to normal prostate (P < 0.05). Hierarchical cluster analysis of metabolite levels distinguished between normal and malignant tissue in old but not young mice. While the reduction in tissue citrate resembles human prostate cancer, low levels of choline species in TRAMP tumors suggest atypical phospholipid metabolism as compared to human prostate cancer. TRAMP tumor and normal prostate tissues did not differ in expression of choline kinase, which is overexpressed in human prostate cancer. CONCLUSION Although prostate cancer in TRAMP mice shares some metabolic features with that in humans, it differs with respect to choline phospholipid metabolism, which could impact upon the interpretation of results from biomarker or chemotherapy/chemoprevention studies.
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Affiliation(s)
- Friederike Teichert
- Cancer Biomarkers and Prevention Group, University of Leicester, Leicester, UK
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184
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Hanif S, Shamim U, Ullah M, Azmi AS, Bhat SH, Hadi S. The anthocyanidin delphinidin mobilizes endogenous copper ions from human lymphocytes leading to oxidative degradation of cellular DNA. Toxicology 2008; 249:19-25. [DOI: 10.1016/j.tox.2008.03.024] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2008] [Revised: 03/29/2008] [Accepted: 03/31/2008] [Indexed: 01/27/2023]
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185
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Lee SC, Chan WK, Lee TW, Lam WH, Wang X, Chan TH, Wong YC. Effect of a Prodrug of the Green Tea Polyphenol (-)-Epigallocatechin-3-Gallate on the Growth of Androgen-Independent Prostate Cancer In Vivo. Nutr Cancer 2008; 60:483-91. [DOI: 10.1080/01635580801947674] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
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186
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Abstract
Advances in science and technology have allowed us to manipulate the mouse genome and analyse the effect of specific genetic alterations on the development of prostate cancer in vivo. We can now analyse the molecular basis of initiation, invasion and progression to metastatic disease. The current mouse models utilise knockout, knock-in or conditional regulation of expression using Cre-loxP technology. Genes that have been targeted include homeobox genes, tumour suppressors and oncogenes, growth factors (and their receptors), steroid hormones and cell-cycle regulators, as well as pro- and anti-apoptotic proteins. Bigenic models indicate that that two 'hits' are required for progression from intra-epithelial neoplasia (PIN) to invasion carcinoma, and two to five hits are needed for metastasis. Here, we discuss the numerous models that mimic various aspects of the disease process, such as PIN, locally invasive adenocarcinoma and metastatic disease. Currently the PB-Cre4 x PTEN(loxP/loxP) mouse is the only model that spans the entire continuum from initiation to local invasion and metastasis. Such mouse models increase our understanding of the disease process and provide targets for novel therapeutic approaches. Hopefully, the transgenic models will become inducible and ultimately allow both temporal and spatial gene inactivation. Compound mutational models will also develop further, with double and triple knock-in or knockout systems adding to our knowledge of the interaction between different signalling cascades.
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187
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Rad AM, Gao X, Deeb D, Gautam SC, Arbab AS. Imaging Mouse Prostate Gland by 3 Tesla Clinical MRI System. ACTA ACUST UNITED AC 2008; 1:60-63. [PMID: 19011697 DOI: 10.2174/1874769800801010060] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
In vivo detection of prostate tumor in animal model will facilitate the investigations that deal with the efficacy of different treatment strategies in different experimental settings. Recently higher field strength dedicated animal MRI system has been used successfully to detect mouse prostate glands and its lesions, however, usefulness of clinical system has not been utilized to its fullest extent. In this short communication we show the advantages and disadvantages of different in vivo imaging parameters of MRI to acquire images of the mouse prostate gland using clinical strength MRI systems.
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Affiliation(s)
- A M Rad
- Department of Radiology, Henry Ford Hospital, Detroit, Michigan
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188
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Multitargeted therapy of cancer by green tea polyphenols. Cancer Lett 2008; 269:269-80. [PMID: 18501505 DOI: 10.1016/j.canlet.2008.04.014] [Citation(s) in RCA: 240] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2008] [Revised: 02/20/2008] [Accepted: 04/09/2008] [Indexed: 12/11/2022]
Abstract
Tea ranks second only to water as a major component of fluid intake worldwide and has been considered a health-promoting beverage since ancient times. For the past two decades, we and others have been investigating the potential cancer preventive and therapeutic effects of green tea and its polyphenolic mixture termed GTP. It has become clear that much of these effects of GTP are mediated by its most abundant catechin, epigallocatechin gallate (EGCG). Large amount of encouraging data from in vitro and animal models has emerged making clear that green tea is a nature's gift molecule endowed with anticancer effects. Epidemiological and geographical observations suggest that these laboratory data may be applicable to human population. Clinical trials of GTP, especially in prostate cancer patients have yielded encouraging results. This article briefly reviews properties of GTP, especially EGCG with reference to multitargeted therapy of cancer.
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189
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Affiliation(s)
- Crissy Dudgeon
- University of Pittsburgh Cancer Institute, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
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190
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Murine prostate cancer inhibition by dietary phytochemicals--curcumin and phenyethylisothiocyanate. Pharm Res 2008; 25:2181-9. [PMID: 18437538 DOI: 10.1007/s11095-008-9574-7] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2007] [Accepted: 03/19/2008] [Indexed: 10/22/2022]
Abstract
PURPOSE Prior studies from our laboratory have demonstrated the efficacy of a combined treatment of low doses of dietary agents curcumin and phenylethylisothiocyanate in effectively suppressing prostate cancer in vitro in human prostate cancer PC3 cells as well as in vivo in immunodeficient mice implanted with PC3 cells. Hence, this study was undertaken to examine the potential chemopreventive properties of the two agents against transgenic adenocarcinoma of the mouse prostate. MATERIALS AND METHODS The efficacy of AIN-76A diet supplemented with 2% curcumin or 0.05% PEITC or a combination of 1% curcumin and 0.025% PEITC for periods of 10 and 16 weeks was tested against adenocarcinoma of the mouse prostate. Immunohistochemistry and Western blot analysis were used to examine the expression of proliferation and apoptotic biomarkers. All statistical tests were two-sided. RESULTS Supplementing AIN-76A diet with dietary phytochemicals curcumin or PEITC either alone or in combination, significantly decreased incidence of prostate tumor formation (P = 0.0064). Immunohistochemistry revealed a significant inhibition of high-grade PIN (P = 0.0006, 0.000069, 0.00029 for a treatment period of 10 weeks and P = 0.02582, 0.022179, 0.0317 for a treatment period of 16 weeks) along with decreased proliferation and increased apoptotic index in the curcumin, PEITC or curcumin and PEITC treated animals, respectively. Furthermore, Western blot analysis revealed that downregulation of the Akt signaling pathway may in part play a role in decreasing cell proliferation ultimately retarding prostate tumor formation. CONCLUSION Our data lucidly evidence the chemopreventive merits of dietary phytochemicals curcumin and PEITC in suppressing prostate adenocarcinoma.
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191
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Chemoprevention of human prostate cancer by green tea catechins: two years later. A follow-up update. Eur Urol 2008; 54:472-3. [PMID: 18406041 DOI: 10.1016/j.eururo.2008.03.100] [Citation(s) in RCA: 129] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2008] [Accepted: 03/19/2008] [Indexed: 12/23/2022]
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192
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Verschoyle RD, Greaves P, Patel K, Marsden DA, Brown K, Steward WP, Gescher AJ. Evaluation of the cancer chemopreventive efficacy of silibinin in genetic mouse models of prostate and intestinal carcinogenesis: relationship with silibinin levels. Eur J Cancer 2008; 44:898-906. [PMID: 18343654 DOI: 10.1016/j.ejca.2008.02.020] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2007] [Revised: 01/14/2008] [Accepted: 02/18/2008] [Indexed: 02/07/2023]
Abstract
Silibinin, a flavonolignan from milk thistle seeds, possesses cancer chemopreventive properties in rodent models of carcinogenesis. We tested the hypotheses that silibinin or silipide, silibinin formulated with phospholipids, delays tumour development in TRAMP or Apc(Min) mice, genetic models of prostate or intestinal malignancies, respectively. Mice received silibinin or silipide with their diet (0.2% silibinin equivalents) from weaning. Intervention with silipide reduced the size of well differentiated TRAMP adenocarcinomas by 31%. Silipide and silibinin decreased the incidence of poorly differentiated carcinomas by 61% compared to mice on control diet. Silipide decreased plasma levels of insulin-like growth factor (IGF)-1 by 36%. Levels of circulating IGF binding protein (IGFBP)-3 in mice on silipide or silibinin were 3.9- or 5.9-fold, respectively, elevated over those in control TRAMP mice. In Apc(Min) mice silibinin, but not silipide, had only a marginal adenoma number-reducing effect. The results cautiously support the advancement of silipide to the stage of clinical investigation in prostate cancer.
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Affiliation(s)
- Richard D Verschoyle
- Cancer Biomarkers and Prevention Group, Department of Cancer Studies and Molecular Medicine, RKCSB, LRI, University of Leicester, Leicester LE2 7LX, UK
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Abstract
It is estimated that nearly one-third of all cancer deaths in the United States could be prevented through appropriate dietary modification. Various dietary antioxidants have shown considerable promise as effective agents for cancer prevention by reducing oxidative stress which has been implicated in the development of many diseases, including cancer. Therefore, for reducing the incidence of cancer, modifications in dietary habits, especially by increasing consumption of fruits and vegetables rich in antioxidants, are increasingly advocated. Accumulating research evidence suggests that many dietary factors may be used alone or in combination with traditional chemotherapeutic agents to prevent the occurrence of cancer, their metastatic spread, or even to treat cancer. The reduced cancer risk and lack of toxicity associated with high intake of fruits and vegetables suggest that specific concentrations of antioxidant agents from these dietary sources may produce cancer chemopreventive effects without causing significant levels of toxicity. This review presents an extensive analysis of the key findings from studies on the effects of dietary antioxidants such as tea polyphenols, curcumin, genistein, resveratrol, lycopene, pomegranate, and lupeol against cancers of the skin, prostate, breast, lung, and liver. This research is also leading to the identification of novel cancer drug targets.
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Affiliation(s)
- Naghma Khan
- Department of Dermatology, University of Wisconsin, Madison, Wisconsin 53706, USA
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194
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195
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Verschoyle RD, Steward WP, Gescher AJ. Putative cancer chemopreventive agents of dietary origin-how safe are they? Nutr Cancer 2008; 59:152-62. [PMID: 18001209 DOI: 10.1080/01635580701458186] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
As cancer chemopreventive agents are intended for use by healthy individuals as prophylactics to prevent or retard the development of cancer, they must be amenable to ingestion over prolonged periods without toxicity. Therefore, putative chemopreventive agents need to undergo stringent testing to ensure their safety with regard to chronic exposure in humans. The diet is thought to be a source of chemopreventive agents, and dietary compounds are generally considered to be of low hazard, albeit this notion has not often been put to the test. Here the safety information available for 5 dietary putative chemopreventive compounds, indole-3-carbinol (I3C), curcumin, quercetin, epigallocatechin gallate (EGCG), and capsaicin is reviewed. For these agents, normal dietary intake, doses used in clinical trials, efficacious doses in rodents, and where available, toxic doses are compared. For curcumin, quercetin and capsaicin, toxicological data is only available from studies in rodents. Information on long-term effects in animals beyond 28 or 90 days is lacking for EGCG. Capsaicin and quercetin are suspected carcinogens. I3C and quercetin can modulate the absorption of other drugs given concomitantly. Without further investigation of their toxicology, it is difficult to recommend any of these agents for long-term use in the healthy population.
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Affiliation(s)
- Richard D Verschoyle
- Cancer Biomarkers and Prevention Group, Department of Cancer Studies and Molecular Medicine, University of Leicester, RKCSB, Leicester Royal Infirmary, Leicester LE2 7LX
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196
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Hwang C, Oetjen KA, Kosoff D, Wojno KJ, Albertelli MA, Dunn RL, Robins DM, Cooney KA, Duckett CS. X-linked inhibitor of apoptosis deficiency in the TRAMP mouse prostate cancer model. Cell Death Differ 2008; 15:831-40. [PMID: 18259199 DOI: 10.1038/cdd.2008.15] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Deregulation of apoptotic pathways plays a central role in cancer pathogenesis. X-linked inhibitor of apoptosis protein (XIAP), is an antiapoptotic molecule, whose elevated expression has been observed in tumor specimens from patients with prostate carcinoma. Studies in human cancer cell culture models and xenograft tumor models have demonstrated that loss of XIAP sensitizes cancer cells to apoptotic stimuli and abrogates tumor growth. In view of these findings, XIAP represents an attractive antiapoptotic therapeutic target for prostate cancer. To examine the role of XIAP in an immunocompetent mouse cancer model, we have generated transgenic adenocarcinoma of the mouse prostate (TRAMP) mice that lack XIAP. We did not observe a protective effect of Xiap deficiency in TRAMP mice as measured by tumor onset and overall survival. In fact, there was an unexpected trend toward more aggressive disease in the Xiap-deficient mice. These findings suggest that alternative mechanisms of apoptosis resistance are playing a significant oncogenic role in the setting of Xiap deficiency. Our study has implications for XIAP-targeting therapies currently in development. Greater understanding of these mechanisms will aid in combating resistance to XIAP-targeting treatment, in addition to optimizing selection of patients who are most likely to respond to such treatment.
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Affiliation(s)
- C Hwang
- Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, MI 48109-2200, USA
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197
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Abstract
The present paper explores the level of evidence required to justify giving dietary advice to the public. There are important practical differences between the development of public health nutrition guidelines and guidelines for clinical practice. While the gold standard for evidence for clinical practice guidelines is a meta-analysis of a number of randomised controlled trials, this is often unrealistic and sometimes unethical for the evaluation of public health nutrition interventions. Hence, epidemiological studies make up the bulk of evidence for nutrition guidelines. Tea and coffee are an interesting case study in relation to this issue. They are two of the most commonly consumed beverages worldwide, yet there is little dietary advice on their use. The evidence for a relationship between coffee or tea consumption and several diseases is discussed. The available studies, predominantly epidemiological, together with animal and in vitro studies, indicate that coffee and tea are both safe beverages. However, tea is the healthier option because it has a possible role in the prevention of several cancers and CVD. While the evidence for such relationships is not strong, the public will continue to drink both tea and coffee, and will continue to ask nutritionists to make recommendations. It is therefore argued that advice should be given on the best available data, as waiting for complete data to become available could have severe consequences for public health.
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Belguise K, Guo S, Yang S, Rogers AE, Seldin DC, Sherr DH, Sonenshein GE. Green tea polyphenols reverse cooperation between c-Rel and CK2 that induces the aryl hydrocarbon receptor, slug, and an invasive phenotype. Cancer Res 2008; 67:11742-50. [PMID: 18089804 DOI: 10.1158/0008-5472.can-07-2730] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Exposure to and bioaccumulation of lipophilic environmental pollutants, such as polycyclic aromatic hydrocarbons (PAHs), has been implicated in breast cancer. Treatment of female rats with the prototypic xenobiotic PAH 7,12-dimethylbenz(a)anthracene (DMBA) induces mammary tumors with an invasive phenotype. Here, we show that green tea prevents or reverses loss of the epithelial marker E-cadherin on the surface of DMBA-induced in situ cancers. To investigate the mechanism(s) leading to a less invasive phenotype, the effects of the green tea polyphenol epigallocatechin-3 gallate (EGCG) on mammary tumor cells were assessed. EGCG reversed epithelial to mesenchymal transition (EMT) in DMBA-treated NF-kappaB c-Rel-driven mammary tumor cells and reduced levels of c-Rel and the protein kinase CK2. Ectopic coexpression of c-Rel and CK2alpha in untransformed mammary epithelial cells was sufficient to induce a mesenchymal gene profile. Mammary tumors and cell lines derived from MMTV-c-Rel x CK2alpha bitransgenic mice displayed a highly invasive phenotype. Coexpression of c-Rel and CK2, or DMBA exposure induced the aryl hydrocarbon receptor (AhR) and putative target gene product Slug, an EMT master regulator, which could be reversed by EGCG treatment. Thus, activation of c-Rel and CK2 and downstream targets AhR and Slug by DMBA induces EMT; EGCG can inhibit this signaling.
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Affiliation(s)
- Karine Belguise
- Departments of Biochemistry, Boston University School of Public Health, Boston, Massachusetts, USA
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van Weerden WM, Schröder FH. The use of PSA as biomarker in nutritional intervention studies of prostate cancer. Chem Biol Interact 2008; 171:204-11. [DOI: 10.1016/j.cbi.2007.11.006] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2006] [Revised: 03/11/2007] [Accepted: 11/08/2007] [Indexed: 10/22/2022]
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Janle EM, Morré DM, Morré DJ, Zhou Q, Zhu Y. Pharmacokinetics of green tea catechins in extract and sustained-release preparations. J Diet Suppl 2008; 5:248-63. [PMID: 19885387 PMCID: PMC2747776 DOI: 10.1080/19390210802414279] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Catechins are a major constituent of green tea. For green tea to have cancer therapeutic benefit, catechin concentrations in the range of 100 nM are required continuously until apoptosis (programmed cell death) is induced. To prolong elevated plasma and interstitial concentrations of catechins, a sustained-release formulation of green tea extract was tested and compared to a commercial green tea extract (Tegreen97®). Sustained-release formulations are usually developed in the pharmaceutical industry to slowly deliver the compound over a period of time and increase the dosing interval. Plasma and interstitial fluid (ISF) pharmacokinetics of catechins were determined following an oral dose in the rat. The sustained-release formulation profile included multiple smaller peaks of total catechins in both plasma and ISF. Interstitial fluid profiles of green tea extract indicate that higher catechins concentration and longer duration in tissue than in blood may make a sustained-release form unnecessary.
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Affiliation(s)
- Elsa M Janle
- Botanical Center In Vivo Core, Purdue University, Department of Foods and Nutrition, West Lafayette, IN 47907, USA.
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