miR-205通过下调ZEB1和ZEB2表达抑制肾小管上皮细胞转分化

The MicroRNA miR-205 inhibits epithelial-messenchymal transition in HK-2 cells by downregulating ZEB1 and ZEB2 expressions

目的探讨miR-205在肾小管上皮细胞转分化的作用机制。方法将miR-205 mimics和scrambled control分别转染HK-2转分化细胞株,采用real-time q PCR检测miR-205和ZEB1、E-cadherin、α-SMA mRNA的表达水平;运用Western blotting检测ZEB1、ZEB2、E-cadherin、α-SMA的表达水平。通过细胞免疫组化检测β-catenin的异位表达情况和E-cadherin的表达情况。结果miR-205 mimics转染HK-2转分化细胞株后,ZEB1和ZEB2的表达水平较高糖组得到大幅下调(P<0.01),而E-cadherin的表达水平较高糖组显著提高(P<0.01),同时间质细胞特征分子α-SMA的表达水平显著降低(P<0.01)。miR-205 mimics也显著抑制了HK-2转分化过程中β-catenin异位表达,在维持上皮细胞的形态方面也起着重要的作用。结论 miR-205可通过下调ZEB1和ZEB2的表达,抑制了肾小管上皮间质转分化进程。

Objective To explore the role of miR-205 in regulating epithelial-messenchymal transition（EMT） in proximal tubular cell line HK-2 cells and the underlying mechanism. Methods HK-2 cells transfected with miR-205 mimics or a scrambled control sequence were examined for miR-205 expressions and mRNA levels of ZEB1, E-cadherin, and α-SMA using real-time q PCR; the protein levels of ZEB1, ZEB2, E-cadherin, and α-SMA were detected with Western blotting. Immunohistochemistry was performed to examine the ectopic expression of β-catenin and E-cadherin expression in the cells. Results The expression levels of ZEB1 and ZEB2 decreased significantly（P〈0.01） while E-cadherin expression was up-regulated（P〈0.01） in cells transfected with miR-205 mimics. Transfection with miR-205 mimics also markedly down-regulated the expression of α-SMA（P〈0.01）, a marker of mesenchymal cells that play an important role in EMT of HK-2 cells. The ectopic expression of β-catenin was inhibited by miR-205 mimics in HK-2 cells. Conclusion miR-205 inhibits EMT in HK-2 cells by down-regulating the expression levels of ZEB1 and ZEB2.