Study on inhibition of expression of cyclin E1 in hepatocellular carcinoma via RNA interference mediated by siRNA expressing vector

Objective To explore the inhibition of expression of cyclin E1 in hepatocellular carcinoma via RNA interference mediated by siRNA expressing vector. Methods A RNA interference DNA template targeting cyclin El gene was designed and synthesized. By ligation, the fragment was inserted into pSileucer1. 0-U6 to construct the recombinant plasmid pSileucer1. 0-U6-cyc-lin E1. The identified recombinant plasmid was introduced into BEL-7402 cells with lipofactamine. The inhibition of cyclin E1 expression was analyzed by RT-PCR and the ratios of S phase and of apoptotic cell were assessed by flow cytometric detection. The viable cells were counted by MTT colorimetry and a cell growth curve was drew to analyze the inhibition of cell proliferation. Results The inhibition of expression of cyclin E1 in BEL-7402 was up to 62% when mediated by pSileucer1. 0-U6-cyclin E1. Thirty-two hours after transfection with recombinant or vector control, the ratio of S phase cells was 19% and 27% , respectively. The apoptotic ratio at 96 hours after recombinant or vector transfection was 13. 1 % and 6. 6%. The cell growth curves indicated that the proliferation of cell transfected with recombinant plasmid was inhibited significantly when compared with control. Conclusion The expression of cyclin E1 could be inhibited successfully by RNA interference induced by siRNA expressing vector. This in turn inhibits the cell growth and induces apoptosis. Our study provided a preliminary resuls in searching of a RNAi therapy of hepatocellular carcinoma.