野生型p53基因转染对人HCC-9204细胞端粒酶活性影响

Influence of wild-type p53 gene tranfection on telomerase activity in human HCC-9204 cell

Purpose:To investigate the effects of tumor suppressor gene p53 on the activity of telomerase/hTERT in human HCC-9204 cell line.Methods:Lipofection-mediated gene transfection method was used to transfect wild-type p53(wt-p53) gene into HCC 9204 cell which expresses telomerse /hTERT and carries mutant-type p53 gene. The expression of p53 was confirmed by Western blot. Both the telomerase activity and hTERT mRNA expression were detected by PCR-ELISA,TRAP-silver staining,in-situ hybridization and RT-PCR methods. The apoptotic appearance was examined by FCM.Results:Higher telomerase activity and hTERT mRNA level were detected in HCC-9204,and they were markedly inhibited after transfection with wt-p53. Meanwhile,decreasing level of bcl-2 protein and appearance of apoptosis were also shown in the transfected cells.Conclusions:Over expression of the exogenous wt-p53 gene does suppress both telomrease activity and hTERT mRNA expression in HCC cell line. There is a p53-dependent regulatory pathway for activation and expression of telomerase/hTERT in HCC.