SFPQ-ABL1–expressing cells are sensitive to BH3 mimetics. (A) Viability analysis of Pu.1/Irf4 DKO cells expressing MSCV, BCR-ABL1, or SFPQ-ABL1 treated with a dose titration of navitoclax, venetoclax, or S63845. MSCV control cells were treated in the presence of IL-7. Data are normalized to vehicle control (0.001% dimethyl sulfoxide [DMSO]; not shown on graphs), and nonlinear regression analysis was performed to fit dose–response curves and determine 50% inhibitory concentration (IC50) values (shown in table). Data are presented as mean ± standard error of the mean (n = 3). (B) western blot analysis of Pu.1/Irf4 DKO cells treated with 10 µM imatinib for 16, 24, or 48 hours. (C) western blot analysis of Ba/F3 cells treated with a dose titration of imatinib for 6 hours. (D) Viability analysis of Pu.1/Irf4 DKO cells expressing MSCV, BCR-ABL1, or SFPQ-ABL1 treated with a dose titration of ABT-263 or S63845 in the presence (100 nM or 1 µM) or absence (DMSO) of imatinib. MSCV control cells were treated in the presence of IL-7. Data are normalized to vehicle control (0.001% DMSO; not shown on graphs), and nonlinear regression analysis was performed to fit dose–response curves. Data are presented as mean ± standard error of the mean (n = 5).