Fig. 3.

Silencing of SPRY2 increases ERK and Akt activation, and MEK inhibitor prevents the decreased cell proliferation of SPRY2 KD. (A) U87 or GSC1 cells transduced with tet-Ctrlsh or tet-SPRY2sh were treated with or without 1 µg/mL doxycycline for 72 hours, serum- (U87) or EGF and FGF2- (GSC1) starved overnight, then treated with EGF (50 ng/mL) for the indicated times. Immunoblotting was performed with the indicated antibodies. (B) Immunoblots for the indicated proteins in U87 tet-SPRY2sh cells (± Doxy) pretreated with the indicated concentrations of PD98059 or dimethyl sulfoxide (DMSO), and stimulated with EGF (20 ng/mL) for 20 minutes. (C) Measurement of cell proliferation of U87 tet-SPRY2sh cells (± Doxy) in the presence of DMSO or 10 µM PD98059. Mean ± SEM of at least 3 independent experiments. **P < 0.01, ***P < 0.001.