miR-200c对三阴性乳腺癌细胞系上皮间质转化的影响*
Effects of miR-200c on epithelial-mesenchymal transition of triple negative breast cancer cell lines

目的:探讨miR-200c对三阴性乳腺癌细胞系上皮间质转化的影响。方法:选取三阴性人乳腺癌细胞系BT549、MDA-MB-231和非三阴性人乳腺癌细胞系MCF-7、SK-BR-3为研究对象,各细胞系按转染情况分为A组(miR-200c模拟物/Lipo2000组)、B组(miR-200c阴性对照物/Lipo2000组)、C组(miR阴性对照物/Lipo2000组)、D组(Lipo2000组)、E组(空白对照组)。分别提取各组细胞的总RNA和蛋白,通过RT-PCR检测Slug和E-cadherin mRNA表达水平,通过Western blot检测Slug和E-cadherin蛋白表达水平。采用划痕实验检测BT549和MDA-MB-231的迁移能力。结果:三阴性细胞系与非三阴性细胞系相比,E组Slug、E-cadherin在mRNA与蛋白水平的表达量,差异有统计学意义(P<0.05)。转染miR-200c后,三阴性细胞系BT549、MDA-MB-231 Slug在mRNA和蛋白水平表达量均降低(P<0.05),E-cadherin在mRNA和蛋白水平表达量均增高(P<0.05),细胞迁移能力下降(P<0.05)。结论:miR-200c可通过下调三阴性乳腺癌细胞系Slug的表达,进而抑制上皮间质转化,降低细胞迁移能力。
Aim: To investigate the role of miR-200c in the epithelial-mesenchymal transition(EMT)of triple negative breast cancer(TNBC).Methods: Human breast cancer lines TNBC cells(BT549 and MDA-MB-231), and non-TNBC cells(MCF-7 and SK-BR-3)were chosen in this study. Each cell line was transient transfected with miR-200c mimic and Lipo2000(group A), miR-200c-control and Lipo2000(group B), miR-negative control and Lipo2000(group C),reagent control(group D)and blank control(group E). Then total RNA and protein were extracted and determined by RT-RCR and Western blot, respectively. Wound healing assay was applied to determine the migratory ability of each group in BT549 and MDA-MB-231.Results: Compared with non-TNBC cells,the expression levels of Slug mRNA and protein were significantly increased,while those of E-cadherin mRNA and protein were decreased(P<0.05). In TNBC cells BT549 and MDA-MB-231, the cells transfected with miR-200c showed significant down-regulation of Slug(P<0.05), up-regulation of E-cadherin(P<0.05), and cell migratory ability was significantly decreased(P<0.05).Conclusion: miR-200c might inhibit the EMT and decrease the migratory ability of TNBC cell lines by down-regulating the expression of Slug