Bmi-1与miR-221-3P在乳腺癌组织和细胞中的表达及相互调控关系

摘要

目的:探讨Bmi-1与miR-221-3P在乳腺癌组织及细胞中的表达水平及相互调控关系.方法:运用RT-PCR检测Bmi-1与miR-221-3P在乳腺癌组织、癌旁组织及MCF-7、MCF-10a细胞中的相对表达水平.运用统计学方法探讨两者的相关性.运用Targetscan软件分析Bmi-1与miR-221-3P存在的结合位点,构建双荧光报告基因载体验证Bmi-1与miR-221-3P的相互结合作用.Western-blotting检测乳腺癌组织及细胞中Bmi-1蛋白的相对表达水平.结果:Bmi-1在乳腺癌组织及MCF-7细胞中呈高表达,而miR-221-3P的表达水平明显下调,两者呈负相关性,相关系数为r= -0.826.在转染克隆有Bmi-1基因3'UTR质粒的实验中,miR-221-3P组与空白组、miR-221-3P抑制剂组、NC组、NC抑制剂相比较, P<0.05,差异极显著.降低Bmi-1的表达水平之后,miR-221-3P的表达水平显著上调.结论:Bmi-1在乳腺癌组织和细胞中呈高表达,miR-221 -3P在乳腺癌组织和细胞中呈低表达,miR-221 -3P负性调控Bmi-1的表达,为阐明乳腺癌的发病机制指明方向.%Objective:To investigate the expression level of Bmi-1 and miR-221-3P in breast cancer tissues and cells and regulatory interaction.Methods:The relative expression levels of Bmi-1 and miR-221-3P in breast cancer tissues,adjacent tissues and MCF-7,MCF-10a cells were detected by RT-PCR.Use the statistical methods to explore their correlation.The binding sites between Bmi-1 and miR-221-3P were analyzed by argetscan soft-ware.Constructe the luciferase vector to verifiy the interaction between Bmi-1 and miR-221-3P.The relative ex-pression level of protein in breast cancer tissues and cells were detected by Western-blotting.Results:The expres-sion of Bmi-1 in breast cancer tissue and MCF-7 cells was high,and the expression level of miR-221-3P de-creased significantly.There was a negative correlation between miR-221-3P and Bmi-1,the correlation coefficient was r= -0.826.The co-transfection of MCF-7 cells with miR-221-3P mimics and psiCHECK-2-Bmi-1 3'UTR significantly inhibited luciferase activity(P<0.05),when compared with control,miR-221-3P inhibitor,neg-ative control,NC inhibitor group.After decreasing the expression level of Bmi-1,the expression level of miR-221-3P increased significantly.Conclusion:The expression of Bmi-1 in breast cancer was high,the expression of miR-221-3P was low in breast cancer,the miR-221-3P negatively regulates the expression of Bmi-1,which indicates the direction for clarifying the pathogenesis of breast cancer.