【摘要】 目的：靶向沉默人乳腺癌细胞Survivin与雌激素受体-α(ER-α) 36双基因的表达，探讨其对乳腺癌MDA-MB-231细胞增殖与凋亡的影响。方法：采用生物信息学技术设计并构建RNAi片段（siRNA-ER-α36），转染乳腺癌MDA-MB-231细胞株。采用噻唑蓝染色法检测细胞增殖情况。采用RT-PCR、Western blot方法检测细胞中Survivin、ER-α36与凋亡蛋白Caspase-3的mRNA及蛋白表达情况；流式细胞术检测转染细胞凋亡率。结果：RNAi片段成功转染MDA-MB-231细胞，24 h转染率的平均值为68%,48 h转染效率可达76%(P<0.01)。与空白对照组比较，RNAi片段转染后MDA-MB-231细胞Survivin和ER-α36基因的mRNA和蛋白含量明显下降（P<0.05），而上调Caspase-3凋亡蛋白的表达；MDA-MB-231细胞增殖能力降低（P<0.05），凋亡率升高（P<0.05）。结论：RNAi靶向沉默并下调Survivin与ER-α36基因的表达，上调Caspase-3凋亡蛋白的表达，从而抑制乳腺癌MDA-MB-231细胞增殖，促进细胞凋亡，提示RNAi沉默可成为对乳腺癌相关基因功能研究的主要技术之一。更多还原

【Abstract】 Objective:To explore the effect of RNA interference on human breast cancer MDA-MB-231 cell proliferation and apoptosis by inhibiting Survivin and ER-α36 double expression. Methods:RNAi fragment(siRNA-ER-α36)was designed and constructed by bioinformatics technology and transfected into breast cancer MDA-MB-231 cell line. Cell proliferation was detected by thiazol blue staining. RT-PCR and Western blot were used to detect the mRNA and protein expression of Survivin, ER-α36 and apoptosis protein Caspase-3. The apoptosis rate of transfected cells was detected by flow cytometry. Results:RNAi fragments were successfully transfected into MDA-MB-231 cells, the average transfection rate of 24 h was 68%, and the transfection efficiency of 48 h was 76%(P<0.01). Compared with the blank control group, the mRNA and protein contents of Survivin and ER-α36 genes in MDA-MB-231cells transfected with RNAi fragment were significantly decreased(P<0.05), while the expression of Caspase-3 apoptosis protein was up-regulated. The proliferation ability of MDA-MB-231 cells was decreased(P<0.05), and the apoptosis rate was increased(P<0.05).Conclusion:RNAi targeted silencs and down-regulats the expression of Survivin and ER-α36 genes, up-regulats the expression of Caspase-3 apoptosis protein, thereby inhibits the proliferation of breast cancer MDA-MB-231 cells and promots cell apoptosis, suggesting that RNAi silencing can become one of the main technologies for the study of breast cancer related gene function.更多还原