重组腺相关病毒介导MDA-7基因表达抑制肝癌形成的体内实验研究  

rAAV-PEG-MDA-7 inhibits the growth of hepatocellular carcinoma in vivo

作　　者：徐波[1] 李书华[2] 蔡文松[1] 翁杰锋[1] 朱光辉[1] 夏金堂[1] 

机构地区：[1]广州医学院附属广州市第一人民医院普外科,510180 [2]广州医学院病理教研室

出　　处：《中华普通外科杂志》2008年第12期928-931,共4页Chinese Journal of General Surgery

基　　金：广东省社会发展领域科技计划资助项目（53056）,（63089）

摘　　要：目的探讨含PEG启动子的腺相关病毒介导的黑色素瘤分化相关基因MDA-7（rAAV-PEG-MDA-7）在裸鼠体内的抗肝癌作用及机制。方法构建肝癌细胞HepG2裸鼠皮下移植瘤模型，尾静脉注射编码重组可溶性MDA-7蛋白的重组腺相关病毒载体rAAV—PEG—MDA-7，观察对肝癌生长的抑制作用。采用RT—PCR、免疫组化、Western blot及ELISA方法分析MDA-7的体内表达情况；Tunnel法和免疫组化检测MDA-7对肿瘤细胞的诱导凋亡和微血管生成抑制效应。结果荷瘤裸鼠尾静脉注射rAAV—PEG—MDA-7后，裸鼠肝细胞中有MDA-7表达，其他组织中无MDA-7表达；血清中MDA-7蛋白持续表达，注射2w后蛋白表达达高峰（200ng／ml）；裸鼠皮下瘤生长受抑制，抑瘤率为62％；Tunnel及免疫组化分析显示，rAAV—PEG—MDA-7可诱导肿瘤细胞凋亡及抑制肿瘤微血管形成。结论含PEG启动子的重组腺相关病毒表达系统rAAV—PEG—MDA-7具有良好的肿瘤靶向性和肝向性，MDA-7在裸鼠肝脏中高效表达，可抑制肝癌生长，其抗肿瘤机制可能为通过诱导肿瘤细胞凋亡及抑制肿瘤血管生成的协同作用。Objective To investigate the anti-tumor effect of the recombined adeno-associated virus encoding melanoma differentiation -associated gene-7 （MDA-7） regulated by progression-elevated gene （PEG） promotor on human hepatocellular carcinoma （HCC） in nude mice. Methods A nude mouse model of subcutaneously implanted HCC cell line HepG2 tumor was established. AAV-PEG-MDA-7 was injected from the tail vain after tumor cell innoculation. RT-PCR, Western blot and immunohistochemical analysis were employed to detect MDA-7 expression in mice; MDA-7 plasma concentration was detected by ELISA assay. Tumor growth was observed, tumor cell apoptosis and angiogenesis in tumor tissues were measured by TUNEL and immunohistochemical analysis. Results Seven days after tumor cell innoculation RT-PCR, Western blot, and immunohistochemistry showed that MDA-7 was only expressed in the liver. ELISA assay showed that the concentration of MDA-7 in plasma was gradually increased to reach the plateau （200 ng/ml）. Tumor growth was significantly inhibited in mice injected with rAAV-PEG-MDA-7, and the tumor growth-inhibiting rate was 62%. TUNEL and immunohistochemical analysis demonstrated significant induction of tumor cell specific apoptosis and reduction of vascular formation in tumor tissues. Conclusions rAAV-PEG-MDA-7 exhibits tumor-specific cytotoxicity and liver tendency, inhibiting tumor growth possibly by tumor cell apoptosis-inducing effect and antiangiogenesis.

关 键 词：癌 肝细胞 细胞凋亡 黑色素瘤分化相关基因 血管形成 

分 类 号：R686[医药卫生—骨科学]