ATAD2 knockdown suppresses cell migration and invasion. (A) Representative images and the average number of migrated cells per field, as determined by migration assay. (B) Representative images and the average number of invaded cells per field, as determined by invasion assay. Three independent experiments were performed, and the data are expressed as the mean ± standard deviation. *P<0.05 vs. Ctrl. ATAD2, ATPase family AAA domain containing protein 2; siRNA, small interfering RNA; Ctrl, control.