Effect of down-regulation of astrocyte elevated gene-1 expression by small interfering RNA inhibits cell proliferation and induces apoptosis in human hepatocellular carcinoma HepG2 cells

Objective To investigate the effect of small interfering RNA (siRNA)-induced astro-cyte elevated gene-1 (AEG-1) down-regulation on the proliferation,apoptosis and cell cycle of human hep-atocellular carcinoma cells and its mechanism.Methods siRNA and AEG-1 siRNA were transfected to Human hepatocellular carcinoma HepG2 cells,respectively.The expression of AEG-1 mRNA was detected by real-time fluorescent quantitative reverse transcription-polymerase chain reaction (FQ-PCR).The cell proliferation was detected by methyl thiazol tetrazolium (MTT) method.The apoptosis and cell cycle were analyzed by flow cytometry.Results Expression of AEG-1 mRNA in AEG-1 siRNA group (0.43 ±0.04)was significantly lower than that in control siRNA group (0.94 ± 0.08) and control group (0.96 ± 0.09)(P ＜0.01),respectively.After treated with AEG-1 siRNA for 72 h,the absorbance values of AEG-1 siRNA group (1.25 ± 0.08) was significantly lower than that in control siRNA group (2.49 ± 0.14) and control group (2.64 ± 0.14) (P ＜ 0.01),respectively.The cell rate in G0/G1 phase (61.38 ± 2.31) ％ was significantly higher than that in control siRNA group (42.15 ± 1.64)％ and control group (41.24 ± 1.97)％(P ＜ 0.01),and the cell rates in S phase (25.36 ± 1.21) ％,G2/M phase (13.26 ± 0.97) ％ were lower than those in control siRNA group (32.52 ± 1.23) ％,(25.33 ± 0.86) ％ and control group (33.60 ±1.24) ％,(25.16 ± 0.79) ％ (P ＜ 0.01),respectively.Conclusion The mRNA expression of AEG-1 is down-regulated by AEG-1 siRNA in human hepatocellular carcinoma cells.Knockdown of AEG-1 expres-sion in human hepatocellular carcinoma cells significantly inhibits cell proliferation and apoptosis,and induces cell arrest in G0/G1 phase of the cell cycle. Key words: Astrocyte elevated gene-1 ;  Cancer, hepatocellular;  Small interfering RNA ;  Apoptotic