Fig. 6.

Rival oncogene-induced growth suppression is rescued by SPRY4 silencing in vitro. a Western blot analysis and quantitative densitometry of the protein expression in SK- MEL-119^NRAS* + iBRAF*cells that ectopically express rival oncogenes and siRNA SPRY4 constructs. Total cell lysate extracts at 48 h were probed with antibodies for BRAF(V600E), BRAF(WT), NRAS(Q61R), NRAS(WT), SPRY4 and internal loading control GAPDH. b Silencing of SPRY4 abrogates the growth inhibition effect of rival oncogene expression in SK-MEL-119^NRAS* cells as compared to siRNA nontarget control (siNTC) vector. c Differential regulation of SPRY4 and p21 proteins upon second oncogene induction. d SPRY4 overexpression and (e) SPRY4 silencing effect on p21 protein expression in the presence of rival oncogene, among suppressive (Red) and nonsuppressive (Green) cell lines was confirmed by western blotting. Student’s t test, doxycycline vs. no-doxycycline, ^◇p ≤ 0.05. The data presented are representative of three independent experiments