The role of autophagy in the epirubicin-induced apoptosis of bladder cancer T24 cells

Objective To study the relationship between apoptosis and autophagy induced by epirubicin (EPI) in the T24 human bladder cancer cell line.Methods The processing concentration of EP was screened out by methyl thiazol tetrazolium(MTT) assay.The experiment was divided into normal control group,EPI group,EPI combined with autophagy inhibitor 3-methyladenine (3-MA) group,and 3-MA group.The T24 cells were cultured and treated with EPI and 3-MA for 24 h.Inhibition of proliferation was measured by using colorimetric MTT assay.Apoptosis rate was determined by using flow cytometry.The expression of bule-associated protein light chain 3 protein (LC3 Ⅰ,Ⅱ) was detected by using immunofluorescence.Reverse transcriptase-polymerase chain reaction (RT-PCR) and Western blotting were used to detect the expression of autophagy-related genes and proteins beclin-1 and LC3 Ⅰ,Ⅱ.Results After treatment with EPI for 24 h,the expression levels of autophagy-related genes and proteins beclin-1 and LC3 were significantly higher than in other groups.As compared with EPI group,the expression of Beclin-1,LC3 and LC3-Ⅱ was significantly declined in 3-MA + EPI group,but proliferation inhibition rate was significantly increased from (36.99 0.69) ％ to (57.65 2.97) ％,and apoptosis rate was significantly increased from (22.35 ± 1.03) ％ to (36.94 ± 1.63) ％.Conclusion EPI-induced autophagy inhibited apoptosis of T24 cells,and inhibition of autophagy by 3-MA enhanced EPI-triggered apoptosis. Key words: Bladder cancer;  Epirubicin ;  Autophagy ;  Apoptosis