Knockdown of Survivin expression with RNA interference induces bladder carcinoma cells apoptosis

Objective To investigate the influence to the biological behavior of bladder cancer cells after downregulation of Survivin and the anti-apoptotic mechanisms of Survivin.Methods One pair of Survivin target sequence-specific small interfering RNA(siRNA)was designed and synthesized,then siRNA/liposome complex was used to transfect bladder cancer cell line-T24 with increasing concentra- tions(50-200 nmol/L).By using MTT assay the proliferation of T24 cells was tested.Apoptosis rate was evaluated by flow cytometric analysis.The expression of Survivin mRNA and Caspase-3 mRNA was de- tected by real-time quantitive PCR.Results SiRNA-Survivin efficiently down-regulated he Survivin ex- pression(mRNA)in a dose-and time-dependent manner.Its maximum effect was achieved at the con- centration of 100 nmol/L,at which Survivin expression level was down regulated by 75.91%.The similar results were found in the inhibition ratio of cell growth,which was 55.29%(P＜0.05).At the same time,Caspase-3 expression level(mRNA)was markedly increased by 239.80% and apoptotie rate by 45.70%,respectively(P＜0.05).Conclusion The application of RNA interfering technology could markedly inhibit the Survivin expression in bladder cancer cell line-T24 and induce apoptosis and inhibit cell proliferation.Survivin inhibits apoptosis through down-regulation of Caspase3 expression.