反转录病毒介导的野生型p53基因诱发人喉癌细胞凋亡的实验研究

为探讨抗癌基因在肿瘤治疗中作用的可能性，以反转录病毒N2A为载体，将p53cDNA及顺式作用元件反向插入N2A两端LTR间的XhoⅠ位点，获得了野生型p53基因反转录病毒重组体。将该病毒重组体转染单向性包装细胞系ψ－2和双向性包装细胞系PA317）筛选后扩增有抗性的细胞克隆，用其产生的新鲜病毒颗粒感染p53基因表达异常的人喉癌细胞系（Hep2）。发现有前病毒整合的受体细胞，细胞染色质浓缩周边化，细胞肿胀，出现凋亡小体，基因组DNA电泳图谱呈阶梯状改变。结果表明反转录病毒介导的野生型p53基因能不同程度地诱导人喉癌细胞凋亡。

Induction of apoptosis by expression of retroviral mediated wild type p53 gene in laryngocarcinoma cell line

The p53 gene is one of the most common targets for genetic abhormalities in human laryngocarcinoma. In this report, the ability of wild-type p53 gene to induce apoptosis of laryngocar-cinoma cell was examined. The wt-p53 gene recombinant retroviral vector was constructed and the PA3l7 packaging cell line producing virus established. The recipient cell lines of Hep2 (laryngocarci-noma) containing the abnormal p53 gene were trans fected in vitro with 1ml fresh retroviral stock pro-duced by the PA317. Southern-blot and Northern-blot were performed using the probe (1. 7Kb p53 cDNA). Assays for in vitro growth characteristics were per formed. The result showed that introduc-tion of wt-p53 greatly suppressed in vitro cellular growth of the laryngocarcinoma cell line and identi-fied that the wt-p53 gene mediated the process of cell apoptosis. In conclusion, the retroviral vector-mediated wt-p53 gene transfer appeared to be able to induce the apoptosis in human laryngocarcinoma bearing multiple genetic lesions. The observation strongly suggests that inactivation of the p53 gene plays a significant role in the pathogenesis of laryngocarcinoma.