目的：探讨新城疫病毒HN基因对肝癌细胞SMMC7721的杀伤作用及其机制。方法： 以脂质体介导方法在体外转染含新城疫病毒HN基因的质粒pVHN 于细胞SMMC7721 24 h后，采用MTT法检测细胞活性；3,5 二羟基甲苯测定其唾液酸含量的变化；丫啶橙/溴化乙锭（AO/EB）染色，荧光显微镜观察细胞形态学改变；以及FCM检测病毒HN基因和HLA-A,B,C的表达。结果： 体外转染pVHN能显著地降低细胞表面唾液酸含量（P<0.05），有效地杀伤肿瘤细胞SMMC7721；荧光显微镜观察可见典型的细胞死亡形态学改变；实验组细胞与对照组比较HN表达差异显著, HLA-A,B,C表达上调。结论： HN基因在体外能够显著降低肿瘤细胞表面唾液酸含量，同时，使其高表达HN抗原，上调HLA-A,B,C表达，从而，可能增强了肿瘤细胞的抗原性和免疫识别，诱导了细胞SMMC7721死亡。

Objective : To investigate the mechanism on cytotoxicity of human hepatoma cells SMMC7721 induced by NDV HN gene. Methods: 24 h after transfected with the mixture of NDV HN gene and liposome in vitro, SMMC7721 cell mortality rate was measured through MTT staining; the content of cell surface sialic acid was measured; the death pattern of SMMC7721 cells was detected by staining with AO/EB; expressions of HN gene and HLA-A,B,C was measured by FCM. Results: Transfected into SMMC7721 cells 24 h later, pVHN reduced the surface sialic acid of SMMC7721 cells（P<0.05）and killed the cells significantly in vitro; the difference of HN gene expression was significantly between experimental groups and control groups, and the HLA-A,B,C expression was upregulated. Conclusions: The HN gene plays an important role in the reduction of sialic acid of SMMC7721 cells and caused the cell death. The expressions of HN gene was significant and HLA-A,B,C expression was upregulated after HN gene tansfected into SMMC7721 in virto. Therefore, immunogenicity and immunoregonization of tumor cells might be increased, so the SMMC7721 cells was killed.

国家973项目（G199011902）