腺病毒介导野生型p53基因转染对人胃癌细胞系的作用

The Growth-Suppressive Effect of Adenovirus-mediated Wild-type p53 Transfection on Gastric Cancer Cell Line

目的 观察野生型p5 3基因 (wtp5 3 )对体外培养人胃癌细胞系生长的抑制作用 ,探讨野生型p5 3基因在胃癌基因治疗中的重要意义。方法 以携带有野生型p5 3基因的复制缺陷型腺病毒 (pAd -p5 3 )为载体 ,转染有p5 3基因突变的人胃癌细胞系BGC -790 1。应用生化染色 ,检测外源基因的转染效率 ;应用免疫组化、原位杂交等方法检测外源基因的表达效果 ;应用细胞计数、MTT法检测pAd -p5 3转染对胃癌细胞生长的抑制效果 ;应用流式细胞仪检测细胞周期。结果 当腺病毒在 10 0MOI以上效靶比转染人胃癌细胞系时 ,转染效率达 10 0 %。转染 3d以后 ,胃癌细胞中突变性p5 3蛋白表达开始减少 ,野生型p5 3mRNA的表达开始增多 ,BGC -790 1细胞生长受到明显抑制 ,流式细胞仪检测显示G0 /G1期细胞数增加 (未转染组 5 6 47% ,转染pAd -p5 3组 79 40 % ,P<0 0 5 ) ,S期细胞数减少 (未转染组 3 0 80 % ,转染pAd -p5 3组 13 81% ,P <0 0 1)。结论 腺病毒介导的野生型p5 3基因体外转染人胃癌细胞 ,可有效抑制胃癌细胞的生长 ,可能成为胃癌基因治疗的手段之一。

Objective To study the inhibitory effects of wild-type p53 on gastric cancer cell lines BGC-7901 and to explore the importance of wild-type p53 in gene therapy for gastric cancer. Methods Adenoviral vector with exogenous wild-type p53 gene was transfected into the gastric cancer cell line BGC-7901 which harbours a mutation in codon 204 of the p53 gene.The transfer efficiency and expression effect of p53 were examined by immunohistochemistry and in situ hybridization. The growth of BGC-7901 cells in vitro was determined by cell counting and MTT assay. Flow cytometric analysis was used for observing cell cycle.Results Transfer efficiency reached 100% in BGC-7901 cells when adenovirus infection ability was over 100MOI. 3 days after transfection, the introduction of exogenous wild-type p53 into the tumor cells resulted in decreased expression of the protein of mutant p53 and increased level of mRNA of wild-type p53 gene. The growth of the BGC-7901 cells was significantly slower after transfection with wild-type p53 gene than that before transfection. The percentage of G 1/G 0 phase of the cells with exogenous wild-type p53 gene was much higher than that of the cells without exogenous wild-type p53 gene.It was 56 47% and 79 40% respectively(P<0 05). The percentage of S phase of the transfected cells was much lower than that of the untransfected cells.It was 30 80% and 13 81% respectively(P<0 05).Conclusions Transfection of wild-type p53 gene mediated by adenoviral vector into the human gastric cancer cell line BGC-7901 could repress the cell growth and may be considered as one of the efficient means of the gene therapy for gastric cancer.