Knockdown effect of Smurf2 siRNA in MDA-MB-231 and MCF-7 cells. (A) MDA-MB-231 cells were transfected with Smurf2 siRNA (siSmurf2) and control siRNA (siControl) at a concentration of 80 pmols. Cells were harvested 36 hours after the transfection, and the silencing effect at the Smurf2 mRNA level was determined using real-time RT-PCR. (B) MCF-7 cells were transfected with Smurf2 siRNA, and control siRNA. The silencing effect at the Smurf2 mRNA level was measured using real-time RT-PCR. The silencing effect of Smurf2 siRNA at the protein level was determined 48 hours post-transfection using western blot in (C) MDA-MB-231 cells and (D) MCF-7 cells.