存活素siRNA表达质粒mU6/survivin的抑癌机制研究  

Anti-cancer mechanism of survivin siRNA plasmid mU6/survivin

作　　者：李莉萍[1] 梁念慈[1] 张志珍[1] 罗超权[2] 

机构地区：[1]广东医学院生物化学与分子生物学研究所,广东湛江524023 [2]中山大学中山医学部生物化学教研室,广东广州510080

出　　处：《现代肿瘤医学》2009年第11期2063-2067,共5页Journal of Modern Oncology

基　　金：广东省教育厅重点学科建设项目(GX0301);广东省自然科学基金(7009923)

摘　　要：目的:在本课题组报导存活素siRNA表达质粒(mU6/survivin质粒)能高效剔降乳腺癌细胞MCF-7中存活素表达的基础上,进一步探讨其抑癌机制。方法:采用MTT法、流式细胞术、Hoechst细胞形态染色和Western blotting等检测mU6/survivin质粒对乳腺癌MCF-7细胞多项生物学指标的影响。结果:mU6/survivin质粒作用后,MCF-7细胞的增殖明显地受到抑制;细胞周期被阻滞在G1期,细胞呈现多核化、巨核化;caspase-3被激活,表达升高;IκBα、Cyt C和P21WAF1蛋白表达升高,NF-κB(p65)蛋白表达无明显改变。结论:mU6/survivin质粒沉默MCF-7细胞中存活素表达后,DNA受损细胞停滞在G1期,细胞增殖受到抑制,此过程与Caspase级联放大、线粒体凋亡通路以及细胞周期调控等有关。细胞逃逸有丝分裂关卡的检查,阻断有丝分裂导致的细胞裂亡是其死亡的主要方式。Objective：To study inhibitory effects of survivin siRNA plasmid（mU6/survivin）constructed and reported on proliferation of breast cancer cells MCF - 7 and its mechanism. Methods： Effect of plasmid mU6/survivin on the cell proliferation was analysed by MTT assay, on the cell cycle by flow cytometry, on the cell morphology by Hoechst staining, and then the activity of caspase - 3 change was determined by its substrate Ac - DEVD - pNA, and some related proteins expression were detected by Western blot. Results： After transfected with plasmid mU6/survivin, the proliferation of MCF - 7 cells were inhibited significantly, cell cycle arrested in G1 phase during 36 h, cells turned to be multinuclear and macronucleus. Protein caspase -3 expressed increasely and was activated, proteins I κBα ,Cyt C and p21^wafl expressed increasely, however, no changes were found in expression of protein NF - κB （ p65 ）. Conclusion： RNA interference of survivin on MCF - 7 cells played a crucial role in cell proliferation and cell cycle progression,and its mechanisms might be related to the caspase cascade, mitochondria apoptosis pathway and cell cycle regulation process, and mitotic cell death might be the main cause of the cell death.

关 键 词：存活素 SIRNA表达质粒 乳腺癌细胞 细胞裂亡 

分 类 号：R730.3[医药卫生—肿瘤]