ABT-737 Treatment induces autophagy in SCLC cell lines. A. Cell lines were treated with doses of ABT-737, CQ, or the combination at doses indicated in Figure 1 for 72 hrs. Protein lysates were harvested and western blots performed using antibodies for LC3 and β-actin. B. LC3-II band intensities from the Western blots shown in A of cells treated with CQ vs. ABT & CQ, normalized to Actin as a loading control. C. H209 and H345 cells were vehicle treated with DMSO (left panels) or treated with ABT-737 (H209, 0.1 μM ABT-737, H345 0.5 μM ABT-737, right panels) for 72 hrs and harvested for electron microscopy. Block arrows indicate autophagosomes. D. The number of autophagosomes per cell prolife was counted for 25 randomly chosen profiles from each sample and averaged. * p < 0.05 relative to DMSO vehicle.