Figure 5
Effect of gefitinib treatment on mTOR signalling.
Cells were treated with DMSO vehicle and 5 nM or 50 nM of gefitinib for 24 hours. Lysates were prepared and run on gels for Western blot with phosphorylation-specific antibodies. Actin was used as the loading control. (a) Effect of gefitinib on P-mTOR and P-p70S6K in PC-9 and H3255 sensitive cells. Inactivation of P-mTOR on the Ser2448 site and of P-p70S6K on the Thr389 was observed. (b) Effect of gefitinib on P-mTOR and P-p70S6K in the less gefitinib-sensitive 11–18 and the gefitinib-resistant H1975 and H1650 cells. Maintenance of P-mTOR on the Ser2448 site and of P-p70S6K on the Thr389 was observed after gefitinib treatment in 11–18 and H1975 cells, while suppression of phosphorylation was achieved with the 50nM of gefitinib in H1650 cells.
