Effect Of EGCG-Induced Autophagy On Bladder Urothelial Cells Carcinoma And The Underlying Mechanis

Objectives:To investigate the effect of epigallocatechin 3-gallate(EGCG)on autophagy in bladder urothelial cells carcinoma and its related mechanism.Methods:1.Bladder cancer 5637?T24 cells were screened for optimal concentration of EGCG by MTT assay.2.Bladder cancer 5637?T24 cells were treated with three different concentrations of EGCG for 24 h,and the effect of apoptosis was detected by flow double staining.3.Two bladder cancer 5637 and T24 cells were treated with different concentrations of EGCG,and the expression levels of apoptosis and autophagic proteins Caspase3,Caspase9,Bax,Bcl2,Beclin1 and LC3 B were detected by Western Blot.4.After the two bladder cancer 5637 and T24 cells were treated with EGCG,the autophagy of each cell group was detected by transmission electron microscopy.5.Western Blot was used to detect the expression of p-AKT and p-mTOR in bladder cancer 5637 and T24 cells after EGCG treatment.6.Bladder cancer T24 cells were screened for optimal growth concentration of PI3K/AKT inhibitor LY294002 and mTOR inhibitor RAPA by MTT assay.7.Bladder cancer cell line T24 was treated with PI3K/AKT inhibitor LY294002,mTOR inhibitor RAPA and EGCG for 24 h,and the effect of cell apoptosis was detected by flow double staining.Select LY294002,RAPA concentrations T24 based pretreatment 24 h,removed LY294002,after RAPA,select low concentrations of EGCG(9mg / L)Cells were treated 24 h,detected by Western Blot autophagy-related factor Beclin1,the level of expression of LC3 B.Results:In this study,after treatment of bladder cancer 5637 and T24 cells by EGCG,it was found that EGCG induced the proliferation of bladder cancer cell lines(T24 and 5637cells),and the expression of apoptosis-related protein(caspase 9?caspase 3 and BAX)was observed.The dose-dependent increase and increased expression of autophagy-associated proteins(LC3B and Beclin1);by TEM,we found that EGCG treatment significantly increased autophagosome formation in T24 and 5637 cells,especially at low doses.In addition,EGCG can also reduce the expression of p-AKT and p-mTOR.After synergistically interacting with PI3K/AKT inhibitor and mTOR inhibitor in bladder cancer T24 cells,flow cytometry showed that the apoptosis rate of bladder cancer T24 cells increased,and Western Blot suggested that the expression of autophagy-related proteins was enhanced.Conclusions:1.EGCG can inhibit the growth of bladder cancer cells and promote the apoptosis of bladder cancer cells.2.EGCG may up-regulate autophagy-related proteins and induce autophagy in bladder cance cellsr.3.EGCG may induce autophagy and promote apoptosis of bladder cancer cells by down-regulating the PI3K/AKT/mTOR pathway.