The effect of p53mut,P53wt and p16 on the expression of Smad4 in lung cancer H1299 cells / 临床外科杂志

ABSTRACT

Objective To investigate the influence of exogenous p53mut, p53wt and p16 on the expression of Smad4 in lung cancer H1299 cells. Methods Target genes (p53mut, p53wtand p16) were amplified by PCR and inserted into effective eukaryotic expression vector pIRES2-EGFP, respectively. These recombinant plasmids were transfected into H1299 cells by lipofectamine. The fluorescence microscope was employed to observe the transfected cells and the expression of EGFP. RT-PCR was used to validate the transfection efficiency. Western blot assay was used to detect the change of the Smad4 expression in H1299, Results Green fluorescence was observed under fluorescence microscope in the transfected H1299 cells at 72 hour post transfection. RT-PCR indicated that p53mut, p53wt and p16 genes were highly expressed in H1299 cell. There was no significant difference in Samd4 expression between the empty plasmid group and control group(P＞0.05). But the expression of Samd4 in p53mut transfected group was decreased(P＜0.05). On the contrary, the expression of Smad4 was increased in the p53wt transfected group and P53wt and p16 co-transfected group. Moreover, the increase was more obvious in the P53wt and p16 cotransfected group(P＜ 0.05). Conclusion P53mut gene transfection reduces the expression of Smad4 and P53wt. The co-infection of p53mut and p16 increases the expression of Smad4 in the H1299 cells. The tumor promoting effect of p53mut and the antitumor effect of p53