Figure 1

P7170 inhibited PI3K/mTOR signaling and the growth of erlotinib-resistant NSCLC cell lines. (A) Exponentially growing H460 cells were seeded in petridishes (2 × 10⁶ cells/dish) and after cell attachment overnight, cells were serum starved for 14-16 h. Cells were then treated for 1 h with P7170 followed by 0.5 h incubation in the presence of 20% fetal bovine serum. Cells were trypsinized and lysed before electrophoresis of cellular extracts for western blot analyses of proteins of interest. (B) Quantification of pS6 and p4EBP1 protein levels in H460 cells after acquisition and analyses of immunofluorescence signals in the Cellomics Array scan platform. H460 cells were seeded in 96-well plates and treated with 0.1 or 1 μM of P7170 for 16 h; drug-containing media was removed and the cells were fixed and stained with antibodies to phosphorylated form of human S6 and 4EBP1 proteins and secondary antibodies conjugated to DyLight 549. Statistical significance values are as follows: *p < 0.05, **p < 0.01, ***p < 0.001. (C) IC₅₀ of erlotinib or P7170 in various NSCLC cell lines after 48 h of treatment.