Green Tea Epigallocatechin-3-Gallate Regulates Autophagy in Male and Female Reproductive Cancer

Abstract

With a rich abundance of natural polyphenols, green tea has become one of the most popular and healthiest nonalcoholic beverages being consumed worldwide. Epigallocatechin-3-gallate (EGCG) is the predominant catechin found in green tea, which has been shown to promote numerous health benefits, including metabolic regulation, antioxidant, anti-inflammatory, and anticancer. Clinical studies have also shown the inhibitory effects of EGCG on cancers of the male and female reproductive system, including ovarian, cervical, endometrial, breast, testicular, and prostate cancers. Autophagy is a natural, self-degradation process that serves important functions in both tumor suppression and tumor cell survival. Naturally derived products have the potential to be an effective and safe alternative in balancing autophagy and maintaining homeostasis during tumor development. Although EGCG has been shown to play a critical role in the suppression of multiple cancers, its role as autophagy modulator in cancers of the male and female reproductive system remains to be fully discussed. Herein, we aim to provide an overview of the current knowledge of EGCG in targeting autophagy and its related signaling mechanism in reproductive cancers. Effects of EGCG on regulating autophagy toward reproductive cancers as a single therapy or cotreatment with other chemotherapies will be reviewed and compared. Additionally, the underlying mechanisms and crosstalk of EGCG between autophagy and other cellular processes, such as reactive oxidative stress, ER stress, angiogenesis, and apoptosis, will be summarized. The present review will help to shed light on the significance of green tea as a potential therapeutic treatment for reproductive cancers through regulating autophagy.

Drug repurposing: A novel strategy to target cancer stem cells and therapeutic resistance

“…The combination of anti-tumor phytochemicals can be more effective in modulating different signaling pathways associated with tumor cell growth which is the common target for anti-tumor action. Piperine, in combination with Paclitaxel, showed a synergistic anti-cancer effect in vitro in the MCF-7 cell line 242 and reduced the IC50 value of paclitaxel in vitro in the MDA MB-231 cell line. 243 Thymoquinone in combination with Gemcitabine synergizes the apoptotic activity in vitro in MCF-7 and T47D cell lines.…”

Epigallocatechin Gallate for the Treatment of Benign and Malignant Gynecological Diseases—Focus on Epigenetic Mechanisms

“…The alkaline environment causes the rapid oxidation of EGCG and is not conducive to protons on the phenolic groups, resulting in the production of a phenolate anion that acts on electrophilic agents such as free radicals in the body [ 50 ]. To prevent the breakdown of EGCG in the body, various methods of delivery are designed, e.g., the encapsulation or formation of a prodrug [ 51 ]. Pro-EGCG was shown to act as an angiogenesis inhibitor in in vitro and in vivo models of endometrial cancer [ 52 ].…”

“…Regarding endometrial cancer, the effect of the EGCC prodrug (pro-EGCG) exhibited antiproliferative, pro-apoptotic, and antitumor actions via the ERK/JNK, Akt, and PI3K/AKT/mTOR/HIF1α signaling pathways [ 51 ]. Antiproliferative, pro-apoptotic, and anticancer effects were reported to occur via the ERK/JNK, Akt, and PI3K/AKT/mTOR/HIF1α signaling pathways in EGCG-treated endometrial cancer cells [ 52 ].…”

Anticancer Mechanism of Flavonoids on High-Grade Adult-Type Diffuse Gliomas

“…Among all the catechins, EGCG is the most abundant and biologically active green tea catechin, which accounts for 50–80% of the total catechins in green tea [ 100 ]. As the structure of EGCG possesses a gallic acid, the presence of the gallate moiety and the extra phenol ring on EGCG enhances its anticancer property, which traps electrons as a scavenger of free radicals and reduces oxidative stress [ 101 ].…”