Microenvironment survival signals induce patient-specific changes in expression of Bcl-2 family proteins that was prevented by sunitinib but not ibrutinib or idelalisib. Comparison of protein levels for unstimulated CLL cells (−) and 2S- or IL4-stimulated cells (+) before and after treatment with 1 µM sunitinib (SUN), idelalisib (IDE), and ibrutinib (IBR). Protein lysates for stimulated patient cells (n = 13 for 2S stimulation, n = 6 for IL4 stimulation) collected 18 to 20 hours after drug treatment were analyzed by immunoblotting using antibodies to the antigens indicated. (A) Representative results for patients P20, P25, and P19. (B) Quantification of relative protein levels for Bcl-xl (i-ii), Mcl-1 (iii), A1 (iv), Bcl-2 (v), and Bax (vi) by analysis of chemiluminescence signals recorded using a CCD camera corrected to the intensities obtained with the β-actin antibody using NIH ImageJ 1.48p software. Data are for 13 patients in subpanels i, iii, iv, v, and vi and 6 patients in subpanel ii; boxes indicate 25th to 75th percentile with the mean indicated as a line. For sunitinib treatment in 2S-stimulated cells, 21 patients were analyzed by immunoblotting (data not shown, significance tests in supplemental Table 2).