Natural Polyphenols and Apoptosis Induction in Cancer Therapy

Abstract

Natural polyphenols are secondary metabolites of plants involved in the defense against different types of stress. Due to their potent antioxidant properties, polyphenols have shown potential health benefits in various oxidative stress-associated diseases such as cancer. Polyphenols can induce tumor cell death and interfere with carcinogenesis, tumor growth, and dissemination. Understanding of tumor biology, identification of novel molecular targets, development of specific antitumor agents, and increase the susceptibility of tumor cells to conventional/ targeted treatments are key points for the achievement of effective anticancer therapies. This review focuses on the antitumor effect of four well known natural polyphenols targeting apoptosis pathways: (-)-Epigallocatechin-3-gallate, resveratrol, curcumin and pterostilbene. In vitro and in vivo studies involving effects and mechanisms of polyphenols-induced apoptosis are discussed, as well as different strategies to improve their bioavailability, which is a main problem, limiting their therapeutic use.