Apoptosis Of Bladder Cancer Cells Induced By Tumor Necrosis Factor Related Apoptosis Inducing Ligand

Objective To evaluate the therapeutic efficiency of tumor necrosis factor related apoptosis inducing ligand(TRAIL) on human bladder cancer cells and bladder epithelial cells. How the TRAIL concentration and inducing time could be related to the apoptosis .To study whether 10-Hydroxycamptothecine(HCPT) could enhanced sensitivity of bladder cancer cells to TRAIL mediated apoptosis.Methods Human bladder cancer cells and bladder epithelial cells were induced by TRAIL at five different concentrations and incubated for 4h,8h,16h,24h,48h. It were used to assess apoptosis of human bladder cancer cells and bladder epithelial cells by Diphenylamine reagent and Flow cytometry.Results Induced by TRAIL protein at different concentrations, characteristic morphological changes related to apoptosis were observed for bladder cancer cells but weren′t observed for bladder epithelial cells ,such as entensive condensation of chromatin, dramatic cell shrinkage, concentration of cytoplasm and formation of apoptotic bodies. Agarose gel electrophoresis of DNA shows "DNA ladder" in bladder cancer cells cultured with TRAIL protein. Data of diphenylamine reaction indicated that the higher percentages of apoptotic cells were related to the treatment with higher concentration of TRAIL protein and longer incubation time. Treatment of bladder cancer cells with a combination of TRAIL protein and HCPT resulted in a synergistic cytotoxic effect. Conclusions apoptosis of human bladder cancer cells line were induced by TRAIL protein but bladder epithelial cells can escape TRAIL mediated apoptosis. TRAIL mediated apoptosis of human bladder cancer cells implies a dose-and-time dependent pattern. HCPT is able to enhance sensitivity of bladder cancer cells to TRAIL mediated apoptosis .