构建Rb、p16、p53、H-ras反义RNA的逆转录病毒载体,利用脂质体介导和病毒感染的方法将其分别转入—存在Rb基因部分缺失、p16低表达、p53缺失和H-ras点突变的胃癌细胞系.观察这些基因对该细胞生长及致癌性的影响,探讨肿瘤相关基因在人胃癌发生、发展过程中的作用.结果表明,通过基因重组技术将多种基因分别重组至逆转录病毒载体PLXSN中,经鉴定获得正插及反插有该基因的重组质粒.将这些质粒分别用脂质体介导和病毒感染的方法转染BGC823细胞,G418筛选2～3周后,获得较高的转染效率.对转染后细胞DNA、RNA进行分析,证明外源性基因已整合人BGC823细胞并获稳定表达.表达有外源性p16、p53基因和H-ras反义RNA的裸鼠致癌性均有明显的抑制作用,而Rb基因对BGC823的恶性增殖能力没有明显抑制.这一结果表明p16、p53、H-ras几个基因的异常可能是导致这一个细胞癌变及最终发展成胃癌的主要原因.本实验进一步明确了胃癌的发生、发展是多基因变异累积的结果.

Our previous investigation have demonstrated that multiple genes alterations, such as deletion of Rb, p53 and p16 gene, point mutation of H-ras gene were detected in cell line and solid tumor of human gastric cancer. We have transfect-ed the independent construct containing Rb, p53, p16 and expression of H-ras antisense RNA respectively into human gastric cancer cell line, and we have analyzed the biological properties of several independent transfectant cell lines, which express exogenous Rb, p53, p16 and H-ras antisense RNA respectively. The cell growth ability was inhibited by introduction of p53 and H-ras antisense RNA, and tumorigenicity also suppressed significantly by p53, p16 and H-ras antisense RNA. These results indicated that alterations of p53, p16 and H-ras gene were involved in human gastric car-cinogenesis.