Up-regulated IDH1 suppressed cell migration and invasion. (A) The cell migration activity showed in wound healing assay was decreased in 143B OE cells and MG63 OE cells, compared with EV cells. KD cells showed significantly higher migration activities. Double headed arrows indicate wound edges. Representative results were shown ((a and b) magnification, ×100). The scale bar represents relative healing rate at 24 h vs. 0 h (c and d). (B) The effect of IDH1 on cell invasion in 143B and MG63 has the same tendency as cell migration. (Magnification, ×200). (C) Up-regulated IDH1 reduced expression of MMP-9, ICAM-1 and VEGF expression in both 143B and MG63 cells, whereas down-regulated IDH1 showed reverse result. Representative western blotting result was shown (**P < 0.01, *P < 0.05).