Inhibitory Effect Of Epigallocatechin-3-Gallate On Bladder Cancer Cells Via Autophagy Pathway

Despite advances in the treatment of genitourinary malignancies, no novel therapies have been approved by the US Food and Drug Administration for urothelial carcinoma, including bladder cancer, in the last 20 years. Epigallocatechin-3-gallate (EGCG), an active ingredient in green tea, is known to effectively inhibit formation and development of tumors. However, the effects and mechanisms of EGCG on bladder cancer are still unclear. In the present study, we demonstrated that low concentration of EGCG induced retarded proliferation and increased apoptosis in bladder cancer cell lines (T24 and 5637 cells) indicated by the increased expression of apoptosis related protein (caspase 9, caspase 3 and BAX). In addition, low dose of EGCG also regulated autophagy pathway associated protein (LC3B II and Beclin), which was blocked by PI3K/AKT inhibitor; moreover, knockdown of ATG5 reversed EGCG-induced apoptosis in 5637 cells, indicating that EGCG might inhibit the bladder cancer through autophagy pathway. Our findings suggest that EGCG may be a novel therapy for bladder cancer treatment by regulating autophagy pathway.