Antiapoptotic protein expression was upregulated in CLL and MCL cells preincubated with agonist mix. (A-C) Expression of antiapoptotic proteins Mcl-1, Bcl-xL, survivin, and Bcl-2 in 14 CLL (Pts 1, 3, 7, 12, 19, 21, 25-27, 48, 51-52, 54, and 59) and 6 MCL (Pts 22, 45, 55, 58, 60, and 66) patient PBMCs and Mino cell line incubated with 2 doses of agonist mix at 12-hour intervals was analyzed by flow cytometry. Representative histograms showing the expression of Mcl-1, Bcl-xL, survivin, and Bcl-2 in a CLL patient sample (Pt 03) treated with agonist mix (A). Antiapoptotic protein expression in CLL patient PBMCs (B) and MCL patient PBMCs/Mino cell line (C) was determined by calculating the geometric mean of fluorescence intensity (GM-FLI) of proteins in CD5⁺/CD19⁺ cells. Agonist mix treatment significantly upregulated the expression of Mcl-1 (2.14 ± 0.51 fold in CLL; 1.874 ± 0.604 fold in MCL) and Bcl-xL (1.47 ± 0.18 fold in CLL; 1.98 ± 0.44 fold in MCL), and survivin (1.3 ± 0.43 fold in CLL; 1.173 ± 0.164 fold in MCL) but not Bcl-2 (1.16 ± 0.11 fold in CLL; 1.091 ± 0.221 fold in MCL) in CLL and MCL cells. (D) A CLL patient PBMC (Pt 25) treated with agonist mix for 12 hours was incubated with BMS-345541 (BMS) (16 μM) or bortezomib (Bortez) (0.064 μM) for 9 hours along with a second dose of agonist mix, with or without IBR (0.1 μM) + VEN (25 nM) and antiapoptotic protein expression was analyzed by calculating GM-FLI of proteins in CD5⁺/CD19⁺ cells using flow cytometry. The data were normalized to DMSO control. Data are expressed as means ± SD. The statistical significance was determined by Student t test. *P < .05, **P < .01, ****P < .0001.