MiR-301b-3p Promotes the Occurrence and Development of Breast Cancer Cells via Targeting HOXA5.

It has been reported that microRNA (miRNA) is an important regulator in various cancers. In this study, it was found by analyzing The Cancer Genome Atlas (TCGA) and bioinformatics database that miR-301b-3p was highly expressed in breast cancer tissue, while HOXA5 was significantly lower expressed in breast cancer. In addition, they had targeted binding sites. The potential functions of miR-301b-3p and HOXA5 in breast cancer were further studied through a series of biological experiments. Expression levels of miR-301b-3p and HOXA5 were detected by qRT-PCR and western blot. The targeted binding relationship between them was verified by dual-luciferase assay. Cell proliferative, migratory, and invasive abilities of cells were detected by CCK-8 cell proliferation assay, wound healing assay, and transwell assay. The apoptosis of breast cancer cells was detected by flow cytometry. These assays indicated that overexpressing miR-301-3p could promote the proliferation, migration, and invasion of breast cancer cells, and inhibit cell apoptosis. It was shown that miR-301b-3p targeted and inhibited HOXA5 expression by detection of HOXA5 expression after overexpressing miR-301b-3p and the result of dual-luciferase assay. Overexpressing miR-301b-3p could decrease the inhibitory effect of overexpressing HOXA5 on cancer cell proliferation, migration, and invasion. These results proved that miR-301b-3p may promote breast cancer cell growth by inhibiting HOXA5 expression, which provided a new potential target for the prognostic treatment of breast cancer patients.