hTERT启动子调控caspase3基因的特异性表达及其抑癌作用  

Specific expression of hTERT promoter driving caspase 3 gene and its anticancer activity

作　　者：杨义军[1] 朱捷[1] 付汉江[1] 孙志贤[1] 郑晓飞[1] 

机构地区：[1]军事医学科学院放射医学研究所

出　　处：《军事医学科学院院刊》2005年第2期116-119,181,共5页Bulletin of the Academy of Military Medical Sciences

基　　金：国家自然科学基金资助项目(30070859);国家重点基础研究发展规划资助项目(G2000057001)

摘　　要：目的:探讨端粒酶催化亚基(hTERT)启动子调控caspase3(半胱天冬酶3)基因在端粒酶阳性肿瘤细胞中表达的特异性及在体内外的抑癌作用。方法:构建hTERT启动子调控的caspase3基因的真核表达载体,通过RT PCR、瞬时转染、MTT法、流式细胞术和动物实验方法,检测hTERT启动子调控caspase3基因表达对肿瘤细胞生长的影响。结果:hTERT启动子调控caspase3基因在端粒酶阳性肿瘤细胞HepG2中有明显表达,而在正常人胚肺成纤维细胞(humanembryoniclungfibroblast,HEL)中未见表达;caspase3表达能对端粒酶阳性肿瘤细胞HepG2、HeLa、Glc和A549细胞的增殖产生明显抑制作用,抑制率为10.5%～37.9%;同时也可以诱导HepG2、HeLa、Glc和A549细胞发生凋亡,凋亡率为15.39%～35.19%;而对端粒酶阴性的正常细胞HEL没有明显的影响。动物实验结果显示,hTERT启动子调控的caspase3基因转染对HepG2细胞的体内增殖具有抑制作用。结论:hTERT启动子调控的caspase3基因表达载体是一种有应用潜力的肿瘤基因治疗载体。Objective: To study the expression specificity of casapse 3 gene driven by hTERT gene promoter in tumor cells with telomerase activity and its effect on the proliferation of telomerase positive tumor cells.Methods:The expression vector of caspase 3 gene driven by the hTERT promoter was constructed and its effect on tumors in vitro and in vivo investigated using RT-PCR,transient transfection,MTT assays,flow cytometry and nude mice experiment. Results:Expression of extrinsic caspase 3 gene under control of the hTERT gene promoter was detected in HepG2 cells, and not in HEL cells. After transfection of phTERT-casapse 3, the proliferation of HepG2,HeLa,Glc and A549 cells was significantly inhibited.The inhibitory rate was 10.5%-37.9% and the apoptosis rate was 15.39%-35.19%, while no effect on HEL cells and the growth of subcutaneous HepG2 tumors in nude mice transfected by caspase 3 gene under hTERT promoter was inhibited. Conclusion: The expression of caspase 3 gene under the control of hTERT gene promoter can restrict toxic effect to telomerase-positive tumor cells, and alleviate the toxic effect on normal cells without telomerase.

关 键 词：基因表达 细胞凋亡 转染 端粒酶催化亚基 启动子 基因治疗 

分 类 号：Q786[生物学—分子生物学]