Fig. 3.

Downregulation of PTEN reduces sensitivity to NVP-AEW541. (A and B) PTEN siRNA leads to a significant reduction in PTEN expression and an increase in Akt phosphorylation. Akt phosphorylation was analyzed, as in Fig. 2, 48 hours after siRNA transfection. PTEN expression was analyzed in the same cell lysates by immunoblotting. (C and D) Downregulation of PTEN reduces sensitivity to NVP-AEW541. Cells were kept in 10% FCS (C) or 1% FCS (D) and treated with 3 µM (C) or indicated concentrations (D) of NVP-AEW541, and effects on growth were determined after 4 days of drug treatment. Results in A–C are derived from 3 independent experiments, and the results in D from 2 experiments. Experiments in A–D were performed in cell culture 4. Error bars indicate the standard error of the mean. P values were determined by Student's t-test.