Effects of silencing SIRT1 gene expression on proliferation and apoptosis of pancreatic cancer cell line PANC1

Abstract

Objective To investigate the effects of SIRT1 gene expression inhibited by shRNA on proliferation and apoptosis of pancreatic carcinoma PANC1 cells. Methods The eukaryotic expression plasmid of short hairpin RNA (shRNA) targeting SIRT1 gene (SIRT1-shRNA) was constructed as pGC-shRNA and transfected into PANC1 cells. There were shRNA-control transfection group and untransfectian control group. The expressions of SIRT1 mRNA and protein were detected with real-time PCR and immunocytochemistry assay, respectively. The growth rate of PANC1 cells was detected by MTT. Activity of caspase-3 and caspase-9 were detected by ELASA. Expressions of Bax, Bcl-2 proteins were determined by Western blotting. ResultsCompared with untransfected group, the inhibition rate of expressions of SIRT1 mRNA and protein were (76.2 ± 10.4) % and (80.1 ± 11.6) %, cytostasis rate was (45.1 ± 6.5) %, caspase-3 and caspase-9 activity was significantly increased, Bax protein was up-regulated, while Bcl-2 protein was down-regulated 48h after transfection. Conclusions Recombinant expression plasmid SIRT1 shRNA could significantly inhibit the expression of SIRT1 gene, and the mechanism may include increased caspase-3 and caspase-9 activity and Bax protein up-regulation, as well as Bcl-2 down-regulation. Key words: Pancreatic neoplasms; SIRT1; Small interfering RNA,Cell proliferation; Apoptosis