RNA Interference Mediates Livin Gene Silencing to Enhance Chemosensitivity of Pancreatic Adenocarcinoma in Vitro

Abstract Purpose RNA interference (RNAi) was used to silence the expression of Livin gene in human pancreatic adenocarcinoma cell line (PANC1), and to investigate the chemosensitivity of PANC1on gemcitabine after the Livin gene knockdown.Methods Using LipofectamineTM2000 as a carrier, a small interfering RNA (siRNA) targeting Livin gene was transfected into PANC1 cells. The mRNA and protein expression of Livin, cleaved PARP (cPARP) and caspase-3 (cCaspase-3) in PANC1 cells were measured by RT-PCR and Western Blot. The protein bands density was analyzed by Image J software, and expressed by the density ratio with the corresponding internal control protein (β-actin). The density ratios of the cPARP and cCaspase-3 protein bands were analyzed by one-way analysis of variance and Student's t-test for comparison of multiple or two groups. A p < 0.05 was considered statistically significant.Results Livin mRNA expression of PANC1 cells significantly decreased after transfection with Livin-siRNA # 1. The cPARP and cCaspase-3 induced by 50 nM gemcitabine were stronger than those induced by 25 nM after 48 hours and 72 hours in PANC1 cells.But the cPARP and cCaspase-3 induced by 100 nM gemcitabine did not significantly change compared with 50 nM. After transfection of Livin-siRNA # 1, cPARP and cCaspase-3 induced by both 25 nM and 50 nM gemcitabine were enhanced. This indicated that the apoptosis of PANC1 cells induced by gemcitabine was enhanced after Livin knockdown.Conclusions RNAi-targeted Livin promotes apoptosis of PANCl cells in vitro through PARP and caspase-3 pathways, and enhances its chemosensitivity to gemcitabine.