MiR-125a-5p inhibits the proliferation and invasion of breast cancer cells and induces apoptosis by targeting GAB2

Abstract

Objective: To investigate whether miR-125a-5p can inhibit the proliferation and invasion of breast cancer cells and induce apoptosis by targeting GAB2. Methods: qRT-PCR was used to detect the expression of miR-125a-5p in normal mammary epithelial cells and breast cancer cell lines; The miR-125a-5p overexpression plasmid was transiently transfected into MDA-MB-157 cells, and the proliferation, invasion and apoptosis of breast cancer cells were detected by CCK8 kit, Transwell chamber and flow cytometry, respectively; Gene silencing was used to knock down GAB2 gene in MDA-MB-157 cells, and the changes of proliferation, invasion, apoptosis and apoptosis-related proteins in breast cancer cells were detected by CCK8 kit, Transwell chamber, flow cytometry and western blot, respectively; The direct interaction between miR-125a-5p and GAB2 was detected by dual-luciferase reporter assay. The miR-125a-5p overexpression plasmid was transiently transfected into MDA-MB-157 cells, and the expression levels of GAB2 and apoptosis-related proteins were detected by western blot. Results: The expression of miR-125a-5p in breast cancer cell lines, MDA-MB-157 cells, MDA-MB-361 cells and MDA-MB-415 cells, was significantly lower than that in normal breast epithelial cells, MCF-10A cells; The proliferation and invasion ability of MDA-MB-157 cells transfected with miR-125a-5p were significantly inhibited, and the apoptosis rate was significantly increased; Since GAB2 knocked down, the proliferation and invasion ability of MDA-MB-157 cells were significantly inhibited, while the apoptosis rate was significantly increased, the Bax protein expression was significantly down-regulated, and the Bcl-2 protein expression was significantly up-regulated; The dual-luciferase reporter assay demonstrated that miR-125a-5p can specifically target GAB2. Transfected with miR-125a-5p, the GAB2 protein expression and Bax protein expression were significantly down-regulated, but the Bcl-2 protein expression was significantly up-regulated. Conclusion: miR-125a-5p inhibits the proliferation and invasion of breast cancer cells and induces their apoptosis by negatively regulating GAB2.

Keywords: Breast cancer; GAB2; apoptosis; invasion; miR-125a-5p; proliferation.