Overexpression miR-211-5p hinders the proliferation, migration, and invasion of thyroid tumor cells by downregulating SOX11.

PURPOSE: This study was aimed to investigate the relationship between miR-211-5p and SOX11, and the effects of their interaction on the proliferation, viability, and invasion of human thyroid cancer (TC) cells.

METHODS: We used quantitative real-time PCR (qRT-PCR) to determine the expression of miR-211-5p and SOX11mRNA in the thyroid tumorous and the adjacent tissues. The target relationship between miR-211-5p and SOX11 was confirmed using dual luciferase reporter gene assay. Flow cytometry, colony formation assay, Transwell assay, and MTT assay were performed to determine the cell-cycle progression, cell apoptosis, proliferation and invasion, respectively. In addition, the tumor formation assay in nude mice was done to assess the effect of miR-211-5p on TC development in vivo.

RESULTS: MiR-211-5p was underexpressed, whereas SOX11 was overexpressed in TC. The overexpression of miR-211-5p inhibited the expression of SOX11. The cell cycle was arrested and the proliferation as well as invasiveness was suppressed by exogenous miR-211-5p in TC cell line. The antitumor role of miR-211-5p was proved by the animal experiment.

CONCLUSION: MiR-211-5p affected the viability, proliferation and invasion of TC by negatively regulating SOX11 expression.