(A) T24 cells were transfected with Gab1 siRNA, treated with LY294002 (20 μM) for 60 min, stimulated with 100 ng/ml EGF for 10 min and then immunoblotted to detect mTOR-pS2448, mTOR-pS2481, p70S6K-pT389, AKT-pS473, ERK-pT202/Y204 and Gab1. (B) E6 cells transfected with Myc-Gab1wt were serum-starved, and the treatment was performed in a similar manner to that described in A. Immunoblotting was performed to detect mTOR-pS2448, mTOR-pS2481, p70S6K-pT389, AKT-pS473, ERK-pT202/Y204, Gab1 and myc. (C) E6 cells were transfected with Myc-Gab1wt and Myc-Gab1ΔPH, treated with 100 ng/ml EGF for 10 min and then immunoblotted to detect mTOR-pS2448, mTOR-pS2481, p70S6K-pT389, AKT-pS473 and Gab1. (D) T24 cells were transfected with raptor siRNA, rictor siRNA and Myc-Gab1wt, treated with 100 ng/ml EGF for 10 min and then immunoblotted to detect mTOR-pS2448, mTOR-pS2481, raptor, rictor, p70S6K-pT389, AKT-pS473, Gab1 and myc. For all experiments, n = 3.