Effects of Green Tea Catechins on Prostate Cancer Chemoprevention: The Role of the Gut Microbiome

Abstract

Accumulating evidence supports green tea catechins (GTCs) in chemoprevention for prostate cancer (PCa), a leading cause of cancer morbidity and mortality among men. GTCs include (−)-epigallocatechin-3-gallate, which may modulate the molecular pathways implicated in prostate carcinogenesis. Prior studies of GTCs suggested that they are bioavailable, safe, and effective for modulating clinical and biological markers implicated in prostate carcinogenesis. GTCs may be of particular benefit to those with low-grade PCas typically managed with careful monitoring via active surveillance (AS). Though AS is recommended, it has limitations including potential under-grading, variations in eligibility, and anxiety reported by men while on AS. Secondary chemoprevention of low-grade PCas using GTCs may help address these limitations. When administrated orally, the gut microbiome enzymatically transforms GTC structure, altering its bioavailability, bioactivity, and toxicity. In addition to xenobiotic metabolism, the gut microbiome has multiple other physiological effects potentially involved in PCa progression, including regulating inflammation, hormones, and other known/unknown pathways. Therefore, it is important to consider not only the independent roles of GTCs and the gut microbiome in the context of PCa chemoprevention, but how gut microbes may relate to individual responses to GTCs, which, in turn, can enhance clinical decision-making.

Potential role of gut microbiota in prostate cancer: immunity, metabolites, pathways of action?

“…In a meta-analysis of nine case-control studies, the risk of PCa was significantly reduced by 57 percent compared with those with the highest green tea intake. Similar results were observed in a recent meta-analysis of 3 case-control and 4 cohort studies, in which the probability of the highest and lowest PCa intake of green tea was significantly reduced by 55% ( 193 ). The Ellagitannins (ETs) extracted from pomegranate juice are also a kind of bioactive polyphenol with a chemoprevention effect on PCa.…”

Overview of BPH: Symptom Relief with Dietary Polyphenols, Vitamins and Phytochemicals by Nutraceutical Supplements with Implications to the Prostate Microbiome

“…Another report by Piwowarski et al in 2021 attributed the role of the microbiota via the influence of polyphenol’s postbiotic metabolites in providing protective mechanism(s) in the pathophysiology of prostate disorders [ 95 ]. Finally, in 2022, Kumar et al reviewed the protective effects of green tea catechins on prostate cancer chemoprevention, and the role the gut microbiome may play (by the metabolism of catechins by gut microbes) to make them more accessible to the body to exert their beneficial health effects [ 96 ]. Thus, examination of the prostate microbiome is an emerging area of study that warrants further investigation, where the microbial environment may improve patient outcomes with greater understanding and knowledge of the inflammatory and protective mechanisms of the microbiota within the bladder and prostate [ 86 , 87 , 88 ].…”

Agri-Food By-Products in Cancer: New Targets and Strategies

“…This might be due to the gut microbiome that acts as an important mediator in regulating the bioavailability of catechins and absorption of bioactive phenolic metabolites. Bacteria, indeed, convert ECGC in different metabolites, thus contributing to ameliorate the PC patients conditions, regulating the inflammation, the hormone levels, and other known and unknown pathways [ 146 ].…”