miR-125b通过靶向结合ETV6调控Hs578T的侵袭转移

目的 研究miR-125b在乳腺癌中的表达,尤其是其对乳腺癌迁移侵袭的作用以及该过程所涉及的分子机制。 方法 (1)用实时荧光定量PCR检测23对临床组织样本中miR-125b及靶基因ETV6的表达水平;(2)用实时荧光定量PCR、双荧光报告验证靶基因;(3)在细胞中瞬时转染miR-125b mimics,并用划痕、transwell迁移、侵袭及Western blot检测体外乳腺癌细胞的迁移侵袭能力及上皮间质转化的变化;(4)用靶基因敲减实验进一步验证靶基因的准确性。 结果 (1)与正常组织相比,乳腺癌组织中miR-125b的表达显著降低(P<0.001),ETV6的表达显著增高(P<0.05);(2) ETV6为miR-125b的靶基因;(3)与对照相比,上调的miR-125b可显著抑制Hs578T的迁移和侵袭(P<0.001),并抑制EMT的发生;(4)敲减ETV6对Hs578T的作用与miR-125b过表达一致。 结论 miR-125b在乳腺癌中低表达,miR-125b通过靶向结合ETV6 3’UTR抑制该基因的表达,从而抑制Hs578T的迁移、侵袭及上皮间质转化的发生。因此,miR-125b可作为抑癌基因发挥作用。 

miR-125b regulates invasion and migration by targeting ETV6 in Hs578T breast cancer cells

Objective To analyze miR-125 b expression in breast cancer, specifically its effects on cell migration and invasion and to explore the mechanism of this process. Methods (1) Real-time PCR was used to detect the expression level of miR-125b and ETV6 in tumors and adjacent non-tumor breast cancer samples; (2) Real-time PCR and dual-luciferase reporter assay were used for target identification. (3) The migration and invasion ability in vitro and the change of epithelialmesenchymal transition were detected by wound healing assay, transwell migration and invasion assay and western blot respectively after instantaneously transfected with miR-125b mimics; (4) The knockdown assay was used for further confirmation. Results (1) As compared with adjacency non-tumor tissues, the expression level of miR-125b in breast cancer tissues was down-regulated (P < 0. 001) and ETV6 was up-regulated significantly (P < 0. 05); (2) ETV6 is the target gene of miR-125b; (3) Compared to control group, the migration and invasion of miR-125b overexpressing Hs578T cells was obviously inhibited in vitro (P < 0. 001), so was epithelial-mesenchymal transition; (4) The effect of ETV6 down-regulation was consistent with miR-125 b overexpression in Hs578T cells. Conclusion miR-125b was downregulated in breast cancer. It remarkably inhibited migration, invasion and EMT of Hs578 T cells by suppressing the expression of ETV6 through targeting its 3'UTR. In general, miR-125b possibly played a role as antioncogene in breast cancer.