Mitogenic effect of FRS3 over-expression and functional redundancy. A: Immunoblot analysis showing FRS3-Myc protein over-expression in DU145 cell line compared to empty vector control cell line following stable transfection with FRS3. B: FRS3 over-expression enhances cell proliferation in DU145 in response to full media and different FGFs. C: FRS2 knock down is compensated for by FRS3 over-expression in proliferation assay in response to different FGF stimulation. Inset image shows immunoblot representative of FRS2 down-regulation following siRNA transfection in DU145 cells. D: FRS3 over-expression reverses the inhibitory effect of FRS2 suppression by siRNA on pERK activation. *p < 0.005.