miR-206抑制SDF-1/CXCR4信号活化诱导的乳腺癌细胞迁移和增殖

MiR-206 Suppresses Breast Cancer Cell Migration and Proliferation Induced by SDF-1/CXCR4 Signaling

目的研究miR-206在乳腺癌细胞中的作用及其机制。方法 MDA-MB-231细胞分别转染miRNA-NC和miR-206 mimic后,荧光显微镜观察转染效率。同时,细胞添加不同剂量(20 ng·m L^(-1)和40 ng·m L^(-1))基质细胞衍生因子1(SDF-1)处理,利用Transwell法检测细胞迁移,噻唑蓝(MTT)法检测细胞增殖,qRT-PCR法检测细胞中CXC趋化因子受体4(CXCR4)mRNA表达水平,Western blot检测细胞中CXCR4蛋白表达水平。结果 miRNA-NC组和miR-206 mimic组细胞转染效率分别为(83.4±6.3)%和(87.6±8.3)%。与对照组比较,SDF-1显著促进细胞迁移和增殖(P<0.05)。miR-206 mimic转染明显抑制细胞迁移和增殖(P<0.05)。SDF-1处理促进细胞中CXCR4 mRNA和蛋白的表达水平(P<0.05)。miR-206 mimic转染则抑制CXCR4蛋白表达水平(P<0.05),但不影响CXCR4 mRNA表达(P>0.05)。结论miR-206通过抑制CXCR4表达拮抗SDF-1诱导乳腺癌细胞迁移和增殖作用。

Objective To explore the role of miR-206 in the breast cancer cells as well as its mechanism. Meth-ods Following the transfection of miRNA-NC and miR-206 mimic into MDA-MB-231 cells,the transfection effi-ciency was observed with a fluorescent microscope. Meanwhile,these cells were conditioned with different doses（20 ng·mL - 1 and 40 ng·mL - 1 ）of stromal-derived factor-1（SDF-1）. Cell migration was evaluated by Transwell as-say. Cell proliferation was determined by MTT assay. The mRNA expression of CXC chemokine receptor 4（CXCR4） was analyzed by qRT-PCR method. Protein expression of CXCR4 was analyzed by Western blot. Results The trans-fection efficiency of the miRNA-NC group and the miR-206 mimic group was（83. 4 ± 6. 3）% and（87. 6 ± 8. 3）% . Compared with the control group,SDF-1 significantly promoted cancer cells migration and proliferation（P ﹤0. 05）. Transfection of miR-206 mimic markedly inhibited cancer cells migration and proliferation（P ﹤ 0. 05）. SDF-1 conditioning enhanced the mRNA and protein expression of CXCR4 in cancer cells（P ﹤ 0. 05）. Transfection of miR-206 mimic constrained CXCR4 protein expression（P ﹤ 0. 05）,but did not influence its mRNA expression（P ﹥0. 05）. Conclusion miR-206 counteracted the role of SDF-1 in inducing breast cancer cell migration and prolifera-tion through regression of CXCR4 expression.