Li Li-Ping, Liang Nian-Ci, Luo Chao-Quan
Department of Biochemistry, Zhongshan Medical College, Sun Yat-sen University, Guangzhou, Guangdong, 510089, P.R.China.
Ai Zheng. 2004 Jul;23(7):742-8.
BACKGROUND & OBJECTIVE: Survivin is specifically overexpressed in tumor tissues. Many reports have shown that the abrogation of its functions is useful for tumor therapy. RNA interference is a new technique that proved to be effective for suppressing gene expression. The aim of this study was to construct a siRNA expression plasmid against gene survivin, and then to assess its functions on breast cancer cells MCF-7.
A survivin siRNA plasmid was constructed using a mU6pro vector contained U6 promotor, the expression change of survivin was examined by semi-quantitative reverse transcription polymerase chain reaction (RT-PCR) and Western blot analysis after the plasmid had been transfected into MCF-7 cells, and the effect of the plasmid on the cell cycle and cell proliferation was analyzed by flow cytometry and MTT method,respectively.
Survivin siRNA plasmid knocked down survivin expression in MCF-7 cells obviously, arrested the cell cycle in G1 phase, inhibited the cell proliferation significantly, and promoted cell apoptosis in a tendency.
Survivin expression was knocked down at mRNA and protein levels by RNAi.
生存素在肿瘤组织中特异性过表达。许多报道表明,消除其功能对肿瘤治疗有益。RNA干扰是一种已被证明对抑制基因表达有效的新技术。本研究旨在构建针对生存素基因的小干扰RNA(siRNA)表达质粒,然后评估其对乳腺癌细胞MCF-7的作用。
使用含U6启动子的mU6pro载体构建生存素siRNA质粒,将该质粒转染MCF-7细胞后,采用半定量逆转录聚合酶链反应(RT-PCR)和蛋白质免疫印迹分析检测生存素的表达变化,分别通过流式细胞术和MTT法分析该质粒对细胞周期和细胞增殖的影响。
生存素siRNA质粒明显下调了MCF-7细胞中生存素的表达,使细胞周期阻滞于G1期,显著抑制细胞增殖,并呈促进细胞凋亡的趋势。
RNA干扰在mRNA和蛋白质水平下调了生存素的表达。