腺病毒介导MDA-7/IL-24选择性促进肝癌细胞的凋亡和增殖阻滞

目的 观察MDA-7／IL-24基因对不同p53状态人肝癌细胞HepG2、MHCC97L以及Hep3B和正常的肝细胞L02的选择性杀伤作用，为肝癌的基因治疗提供理论基础。方法 将携带人MDA-7／IL-24基因的腺病毒Ad．mda-7感染人正常肝细胞L02和不同p53状态的肝癌细胞HepG2，MHCC97L、Hep3B。通过逆转录聚合酶链反应方法观察MDA7／IL24基因的表达，酶联免疫吸附法检测细胞培养上清液中MDA-7／IL-24蛋白的浓度，通过四甲基偶氮唑盐染色法及Hoechst染色观察MDA-7／IL-24对肝癌细胞的生长抑制和杀伤作用，Annexin-V和碘化丙啶双染后流式细胞仪检测细胞的凋亡，应用流式细胞仪检测细胞周期。结果 复制缺陷型腺病毒能介导外源基因MDA-7／IL-24在肝癌细胞株HepG2，MHCC97L和Hep3B以及正常细胞L02中高效表达。细胞培养上清液中有MDA-7／IL-24蛋白表达。MDA-7／IL-24能明显抑制各种肝癌细胞的生长，Hoechst染色提示MDA-7／IL-24促进肝癌细胞的凋亡，流式细胞仪提示MDA-7能选择性杀伤肝癌细胞而对正常的肝细胞无影响，细胞周期分析提示MDA-7／IL-24阻滞肝癌细胞在G2／M期，同时对正常的肝细胞没有促凋亡作用和增殖阻滞作用。结论 复制缺陷型重组腺病毒载体Ad．mda-7能介导MDA-7／IL-24基因在人肝癌细胞中高效表达，选择性地杀伤肝癌细胞HepG2、MHCC97L和Hep3B，促进细胞增殖阻滞及诱导肿瘤细胞凋亡而与肿瘤细胞的P53基因的状态无关，同时对正常的肝细胞L02无任何毒性作用。

Adenovirus vector expressing MDA-7/IL-24 selectively induces growth arrests and apoptosis in human hepatocellular carcinoma cell lines independent of the state of p53 gene

Objective To investigate the effect of melanoma differentiation associated gene-7/interleukin 24 (MDA/IL-24) on human hepatocellular carcinoma cell lines HepG2, MHCC97L and Hep3B and normal liver cell line L02 with a different p53 state. Methods The MDA-7/IL-24 gene was transfected into human hepatocellular carcinoma cell lines HepG2, MHCC97L and Hep3B and hepatocyte line L02 with a replication-incompetent adenovirus vector. The mRNA expression of MDA7/IL-24 in HepG2, MHCC97L, Hep3B and L02 cells was confirmed using RT-PCR. Protein expression was confirmed using ELISA assay. MTT assay and flow cytometry were used to study tumor cell proliferation and cell cycle in vitro. Hoecnst and flow cytometry assay after annexin-V and PI staining were performed to indicate the apoptosis effect. Results Exogenous MDA-7/IL-24 gene was expressed in HepG2, MHCC97L, Hep3B and L02 cells. The protein product of MDA-7/IL-24 was confirmed in the supernatant. MTT assay and apoptosis test indicated MDA-7/IL-24 could induce growth suppression and apoptosis of HepG2, MHCC97L and Hep3B but could not in L02. Cell cycle test revealed MDA-7/IL-24 could block those cancer cells in G2/M but not in the normal cell L02. Conclusion M0A-7/IL-24 selectively induces growth suppression and apoptosis in hepatocellular carcinoma lines HepG2, MHCC97L and Hep3B in vitro independent of the state of p53 gene but not in normal liver cell L02. This indicates MDA-7/IL-24 can be a perfect gene for gene therapy in hepatocellular carcinoma.