Inhibitory effects of tumor necrosis factor-related apoptosis-inducing ligand on human bladder carcinoma

Objective To investigate the inhibitory effects of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) gene on the apoptosis and the growth of human bladder carcinoma cells. Methods The cDNA encoding full-length human TRAIL was cloned. The eukaryotic expression vector pEGFP-N1-TRAIL containing enhanced green fluorescent protein (EGFP) gene and expressing TRAIL was constructed, then transfected into EJ cells using a liposome-mediated transfection system. EGFP gene as a report gene was detected by fluorescent microscopy. TRAIL expression was detected by RT-PCR and Western blot. The apoptosis was determined by flow cytometry, and the cell growth inhibition were assessed by MTT, cell doubling generation time and colonyforming efficiency. Results Twenty-four h after transfection, fluorescence microscopy showed great number of EJ cells that expressed green fluorescence in both the pEGFP-N1 group and pEGFP-N1-TRAIL group. The rates of green fluorescent protein positive cells were 38.4% and 35.3% respectively in these two groups (P0.05). RT-PCR and Western blot revealed TRAIL was increased significantly after transfection with TRAIL. A significantly higher rate of apoptosis was found in EJ cells transfected with TRAIL (P0.01).The proliferation of the cells transfected with TRAIL was significantly decreased (P0.01).Conclusion TRAIL may induce apoptosis and inhibit the proliferation of human bladder carcinoma cells, and may become a novel approach to treatment of cancer.