Mechanism of tmor necrosis factor related apoptosis inducing ligand induced apoptosis in colon carcinoma cells

Objective To explore the mechanism of tmor necrosis factor related apoptosis inducing ligand (TRAIL)-induced apoptosis in colon carcinoma cells. Methods Apoptosis, changes of mitochondrial membrane potential, cardiolipin and generation of ROS, activity of Caspase-3, in colon carcinoma cells with treatment of 500 μg/L TRAIL + /-Z-VAD. fmk, were detected by means of flowcytornetry, ELISA and flurometer methods at different time points (0,2,4,6 and 24 h). Results TRAIL could induce apoptosis in colon carcinoma cells significantly. At 4th h, the apoptosis index was 32.98% . Mitochondrial △ψm and cardiolipin were decreased and activity of Caspase-3 increased after treated with TRAIL.The Caspase-3 activity at 4th h was (37.56 ±2.572) μmol/L·h-1·mg-1 protein.But these effects could be inhibited by Caspase inhibitor Z-VAD. fmk. The apoptosis induced by TRAIL was not related with the generation of ROS. Conclusion TRAIL induced apoptosis in the Caspase-dependent manner and damage of mitochondrial inner membrane in colon carcinoma cells.