Characterization of select BL- and DLBCL-derived cell lines. (A) Western blotting for prosurvival proteins, proapoptotic BIM, and TP53 in human B-cell lymphoma lines. Probing for HSP70 was used as a loading control. Note that high TP53 protein levels in unstressed cells are indicative of tumor-driving mutations in the TP53 gene. (B) Quantification of BCL-W protein expression from representative western blotting experiments, normalized to the loading control, HSP70. (C) BCL-W gene expression measured by qRT-PCR. Data were normalized to HMBS housekeeping gene expression. (D) Flow cytometry gating strategy to determine cell viability. Live cells were Annexin V and DAPI double-negative. (E) Sensitivity profile of each cell line to 5 μM BH3-mimetic drugs: S63845 (MCL-1 inhibitor), ABT-199 (BCL-2 inhibitor), ABT-737 (BCL-2, BCL-XL, BCL-W inhibitor), and A-1331852 (BCL-XL inhibitor). Cell viability was measured as in panel D, and normalized to a DMSO-treated control sample. Error bars represent the SD for 3 independent experiments. Significance is indicated for comparisons to DMSO-treated control cells (1-way analysis of variance with Dunnett’s post hoc test, *P < .05, **P < .01, ***P < .001, ****P < .0001).