Antitumor effect of tumor necrosis factor-related apoptosis-inducing ligand gene transfection mediated by adenovirus in human pancreatic carcinoma cell

Objective To investigate the antitumor effect of tumor necrosis factor-related apoptosis-inducing ligand(TRAIL) gene transfection mediated by adenovirus into human pancreatic carcinoma cell line Panc-1,and the mechanisms involved in this effect.Methods TRAIL gene was transfected into pancreatic cancer cell line Panc-1 by an adenovirus vector(Ad-TRAIL).Level of TRAIL mRNA expression was determined using RT-PCR,and TRAIL protein synthesis was evaluated with Western blot.Cell-growth activities were determined by MTT assay.The bystander effect was observed by co-culturing the Panc-1 cells with and without the transfected TRAIL gene at different ratios.Apoptosis in pancreatic cancer cells was detected by flow cytometry.Proaspase-8 and procaspase-3 proteins were determined by Western blot.Results The stable overexpression of TRAIL was detected in Panc-1 cells transfected by Ad-TRAIL.Ad-TRAIL significantly inhibited cell viability of Panc-1 cells.Furthermore,co-culture of cancer cells transfected with TRAIL resulted in the nontransfected cell inhibition by bystander effect.Moreover,the percentage of apoptotic cells was significantly higher in the Ad-TRAIL-treatment group compared to the control groups(P0.01),and there was a diminished amount of procaspase-8 and procaspase-3 after infection with Ad-TRAIL transfection.Conclusions The overexpression of TRAIL gene in Panc-1 cells by Ad-TRAIL exerts a marked antitumor effect,and the mechanisms involved in this effect may be related to proapoptosis and bystander effect.