Abstract: Objective To investigate the effect of prohibitin（PHB） over-expression on proliferation and apoptosis of human hepatocellular carcinoma cell line HepG2 cells. Methods The eukaryotic expression plasmid （pEGFP-N1-PHB） had been constructed and the HepG2 cells were transiently transfected with recombinant plasmid. Measurement of cell proliferation was performed by using MTT assay. Flow cytometry was carried out to detect cell cycle alterations and apoptosis. Results The cell growth curves showed that the proliferation of HepG2 cells were significantly decreased after transfection with pEGFP-N1-PHB as compared with pEGFP-N1 or controls（P<0.05）;At 48 hours after transfection,the proportion of G2/M phase of HepG2 cells in pEGFP-N1-PHB-transfected group was（27.84±0.47）%,significantly higher than in pEGFP-N1-transfected group[（17.21± 0.64）%] or in the non-transfected group[（22.67±0.33）%,P<0.001];The percentage of apoptotic cells in pEGFP-N1-PHB-transfected group was（31.72±0.35）%,much higher than（18.66±0.56） % in pEGFP-N1-transfected or non-transfected cells [（13.47±0.94）%,P<0.001]. Conclusion PHB overexpression might inhibit the proliferation, induce G2/M phase arrest and apoptosis of HepG2 cells.

Key words: Hep G₂ Cells, Prohibitin, Apoptosis, Cell cycle