miR-125b通过靶向结合ETV6调控Hs578T的侵袭转移

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

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。

Objective To analyze miR-125b 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 epithelial- mesenchymal transition were detected by wound healing assay, transwell migration and invasion assay and western blot respectively after instantaneously transfected with miR-125b mimics;（4）Tbe 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 overexpressiug 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-125b overexpression in Hs578T cells. Conclusion miR-125b was downregulated in breast cancer. It remarkably inhibited migration,invasion and EMT of Hs578T cells by suppressing the expression of ETV6 through targeting its 3＇ UTR. In general,miR-125b possibly played a role as antioneogene in breast cancer.