miR-519d significantly inhibits the migration and invasion of OSCC cells. (A) The expression of miR-519d in OSCC cells transfected with miR-519d mimics or miR-NC. (B) MTT experiment demonstrated that overexpression of miR-519d had no significant effect on the proliferation of OSCC cells. (C) The expression of miR-519d in OSCC cells transfected with miR-519d inhibitor or NC inhibitor. (D) MTT assay showed that silencing of miR-519d exhibited less effect on the proliferation of OSCC cells. (E, F) Dysregulation of miR-519d influenced the migration of OSCC cells, suggested by wound healing assay. (G, H) Transwell invasion assay revealed the suppressive role of miR-519d in the invasive abilities of OSCC cells. The fields of migrated and invasive cells on the membrane were captured (magnification × 100). Statistical analysis was performed using the t-tests. The data represent the mean values of three independent experiments. *, P < 0.05, **, P < 0.01. ***, P< 0.001. ****, P<0.0001.