DNA-PKcs失活对c-Myc蛋白表达的影响  

Effect of inactivation of DNA-PKcs on c-Myc protein expression

作　　者：安静[1] 徐勤枝[1] 隋建丽[1] 白贝[1] 臧远胜[2] 周平坤[1] 

机构地区：[1]军事医学科学院放射医学研究所,北京100850 [2]第二军医大学长海医院呼吸内科,上海200433

出　　处：《军事医学科学院院刊》2005年第4期312-315,320,共5页Bulletin of the Academy of Military Medical Sciences

基　　金：国家高技术研究发展计划("863"计划)资助项目(2004AA221160);国家自然科学基金资助项目(30371232)

摘　　要：目的:通过DNA-PKcs表达抑制的细胞模型,研究DNA-PKcs与癌基因c-myc表达调控的关系。方法:利用siRNA技术或抑制剂建立DNA-PKcs表达抑制细胞模型,Western印迹检测DNA-PKcs和c-Myc蛋白表达变化,Northern印迹检测癌基因c-myc的mRNA表达,SEAP检测系统检测c-myc转录活性变化。结果:稳定表达DNA-PKcssiRNA的细胞DNA-PKcs蛋白和c-Myc蛋白表达明显降低,同时c-myc转录活性也被抑制,但c-myc在mRNA水平无明显变化。渥曼青霉素(wortmannin,0.2μmol/L)同样也可抑制c-Myc蛋白表达和转录活性,而对c-myc的mRNA表达无影响。结论:DNA-PKcs参与c-myc基因的表达调控,DNA-PKcs是一个潜在的肿瘤治疗靶分子。Objective： To construct the stable cell models of suppressed DNA-PKcs expression and to study the relationship between DNA-PKcs and oncogene c-myc. Methods： RNAi and inhibitor were used to silence the expression of DNA-PKcs in HeLa cells. The expression of DNA-PKcs and c-Myc protein was tested using Western blotting. At the same time the c-myc mRNA expression was assayed by Northern blotting. SEAP assay was used to estimate the c-myc transcription activity. Results： DNA-PKcs siRNA caused remarkable suppression of DNA-PKcs expression in HeLa cells and these siRNAs also inhibited the oncoprotein c-Myc protein expression and transcription activity. However, the siRNAs had no effect on the c-myc mRNA. Wortmannin （0.2 μmol/L） also could suppress the expression of c-Myc protein and its transcription activity, but had no influence on c-myc mRNA. Conclusion：DNA-PKcs plays an important role in the expression and activity of oncogene c-myc and DNA-PKcs is a potential anticancer target.

关 键 词：原癌基因蛋白质类c-Myc 基因表达 DNA-PKCS RNA干扰(siRNA) 渥曼青霉素 转录活性 

分 类 号：R73-3[医药卫生—肿瘤]