Figure 4

Gefitinib-resistant (GR) cells have higher levels of basal autophagy. (a) Real-time RT-PCR for the expression of LC3A mRNA in parental cells and GR cells from HCC827 or HCC4006 cells. (b) Western blots examining the effects of salinomycin (1 μM) for 48 h in HCC827 parental and GR2 cells. (c) Western blots examining the effects of chloroquine (CQ; 5 μM) for 48 h in HCC4006 parental and GR3 cells. (d) Viability of HCC827 or HCC4006 parental and GR cells following CQ treatment. Cells were treated with CQ (15 μM) for 72 h under normoxic conditions (20% oxygen and 10% FCS). Cell viability was assessed by trypan blue exclusion and the results were normalized to an arbitrary unit of 1.0 for viable cell number immediately before treatment. Results are expressed as the mean (n=3) and s.d.