Chloroquine or 3-methyladenine selectively augments SAHA-induced apoptosis. (A) Time-dependent induction of DNA fragmentation. Ba/F3 cells engineered to express wild-type (p210) or imatinib-resistant (E255K, M351T, T315I) Bcr-Abl were treated with 25 μM CQ, 2 mM 3-MA, 1 μM SAHA, or the indicated combinations for 24 or 48 hours. K562 and LAMA 84 cells were treated with 25 μM CQ, 5 mM 3-MA, 2 μM SAHA, or the indicated combinations also for 24 hours and 48 hours. Percentages of cells with subdiploid DNA were determined by PI/FACS. Results shown represent the mean of 3 independent experiments. Error bars indicate the standard error of the mean (SEM). (B) Targeting autophagy selectively enhances SAHA-induced apoptosis in Bcr-Abl–expressing cells. Ba/F3 vector control cells and Ba/F3 p210 and T315I cells, cultured in the presence of 20 units/mL of IL-3, were treated with 25 μM CQ, 2 mM 3-MA, 1 μM SAHA, or the indicated combinations for 48 hours. Percentages of apoptotic cells were quantified by PI/FACS. n = 3; error bars represent the SEM. *P < .05.