Figure 1.

(a) Adenosine triphosphate-based cell viability experiments comparing sensitivity of KPL-4 parental (black) and KPL-4PR pool cells (green) to the selective PI3K inhibitor GDC-0941, the dual PI3K/mTOR inhibitor GDC-0980 and the dual HER2/EGFR inhibitor lapatinib. (b) Phospho-protein arrays probed with lysates from KPL-4 parental and KPL-4PR cells showing elevated phosphorylation of two phospho-sites on AKT in KPL-4PR cells. (c) Western blot of lysates from cells treated with increasing concentrations of GDC-0941, showing elevated basal pAKT in KPL-4PR cells and a shift in the IC₅₀ for AKT inhibition in KPL-4PR cells.