Smurf2 knockdown impairs cell motility. (A) Wound healing assay was done to evaluate the migration potential of MDA-MB-231 cells after silencing Smurf2 expression. Fifty-six hours after the transfection of siRNA, cells were wounded and monitored with a microscope every 6 hours. (B) The migration was determined by the rate of cells filling the scratched area and the result represented as mean ± standard deviation (n = 3). NC-Negative control without siRNA.