目的:探讨survivin基因启动子调控的siRNA真核表达载体对HeLa细胞中stathmin基因表达的肿瘤特异性封闭作用。方法:合成针对人stathmin基因的siRNAcDNA寡核苷酸链退火形成双链,连接入经BamHI和HindIII双酶切后的pSilencer4.1-CMVneo真核表达载体。PCR扩增suvivin基因启动子并测序,用EcoRI和BamHl分别双酶切,连接至经相同内切酶消化的载体,获得survivin启动子调控的siRNA真核表达载体,酶切及测序鉴定。脂质体法转染重组质粒人HeLa细胞,G418筛选。RT-PCR扩增stathmin基因,检测其对stathmin基因表达的干涉效果;流式细胞仪分析转染后HeLa细胞增殖周期的改变。结果:经酶切及测序鉴定,成功构建重组质粒;RT—PCR结果显示所构建的干涉载体可有效封闭stathmin基因表达;流式细胞仪分析结果显示,Hale细胞在stathminsiRNA作用下G2/M期细胞的比例明显增加。结论:survivin基因启动子调控的siRNA真核表达载体可有效地封闭HeLa细胞中stathmin基因表达并使HeLa细胞阻断于G2/M期,为以stathmin基因为靶点的恶性肿瘤生物治疗奠定了理论基础。
Objective:To evaluate the interferencing effects of stathmin gene siRNA driven by survivin gene promoter in HeLa cell line. Methods: Double chain siRNA for stathmin gene were obtained through annealing of ohgonucleotide of siRNA, then cloned into pSilencer4.1 - CMV vector together with PCR derived survivin gene promoter to construct the recombinant eukaryotic expression vectors : pSilencer4.1 - surp neo. The recombinant vectors were identified by enzyme digestion analysis and DNA sequencing. Then HeLa cells were transfected with pSilencer4.1 - surp neo and pSilencer4.1 -CMV negtive control ,then subjected to G418 selection. In G418 -resistant cells, the interferencing effect was detected by RT - PCR and cell cycle was detected by flow cytometry. Results : Enzyme digestion analysis and DNA sequencing showed that survivin promoter - directed siRNA on stathmin gene were cloned into pSilencer4.1 - CMV neo vector. The result of RT - PCR indicated that the transcription of stathmin gene was suppressed by siRNA. Flow cytometry test found that cells of G2/M stage increased significantly. Conclusion: The transcription of stathmin gene is inhibited effectively by the constructed RNAi eukaryotic expression vectors in HeLa cells.