Green Tea Components: In Vitro and In Vivo Evidence for Their Anticancer Potential in Colon Cancer

Abstract

Green tea consumption has been implicated in various biological activities, with particular emphasis on its anticancer properties. The antineoplastic effects of green tea are primarily attributed to its rich polyphenol content, among which, epigallocatechin-3-gallate (EGCG) is recognized as the most bioactive and potent catechin, responsible for the majority of its anticancer activity. This review provides a detailed examination of the in vitro and in vivo effects of green tea components, focusing on their potential therapeutic implications in colorectal cancer. The molecular mechanisms of action and bioactive constituents of green tea are systematically discussed, alongside an evaluation of experimental evidence supporting their efficacy. Furthermore, insights into the relationship between green tea dietary intake and colorectal cancer risk are analyzed, with a particular emphasis on clinical data and findings from meta-analyses involving patients diagnosed with colon cancer. The aggregated evidence underscores the necessity for well-designed randomized controlled trials and longitudinal cohort studies to substantiate the role of green tea as a chemopreventive agent. Additionally, future investigations should prioritize determining the optimal dosages, the appropriate durations of consumption, and the potential modulatory effects of dietary or lifestyle factors on green tea’s anticancer efficacy.