The effects of short interfering RNAs on E2F-1 gene expression and biological behaviors of gastric cancer ceIl line MGC803

Objective To investigate the effects of RNA interference(RNAi)targeting E2F-1 on biological behaviors of gastric cancer cell line MGC803.Methods E2F-1-siRNA or negative control-siRNA was transfected into gastric cancer cell line MGC803 cells.Forty-eight h later,the expression of E2F-1 mRNA and protein in gastric cancer cell fine MGC803 was detected by real-time quantitative PCR and Western blot respectivelv.Cell cycle was examined by flow cytometry,and the proliferative rate of MGC803 cells tegted by MTT assay.Results E2F-1-siRNA effectively inhibited the expression of E2F-1 mRNA and Drotein and influenced proliferation of MGC803 cells.As compared with negative control and nontmsfected groups,the expression levels of E2F-1 mRNA and protein were decreased by 84.8%,85.3%(P＜0.05),and 77.2%,79.6%,and proliferation of MGC803 cells was suppressed by 69.0%and 81.6%(P＜0.05)in E2F-1-siRNA transfection group,respectively.E2F-1-siRNA promoted accumulation of more DNA of MGC803 cells at G2/M phase,and the rate of DNA content in G2/M phase in E2F-1-siRNA trailsfection group was(54.98±3.46)%,which was significantly higher than(43.07±3.82)% in negative control group,and(31.47±2.12)%in non-transfection group(P＜0.05).Conclusion E2F-1 gene repression by RNAi can decrease the DNA content in G1 phase of MGC803 cells,which can arrest the cells in G2/M phase and inhibit the proliferation of MGC803 cells. Key words: Gastric carcinoma; Small interfering RNA; Cell cycle; Proliferation