Figure 5. Heightened proliferation in UM-CLL subgroup is BTK-dependent.

(A) Correlation between p-BTK and CLL proliferation. Linear regression of total and statistical analysis was conducted using GraphPad Prism 6. (B) Efficiency of BTK knock-down assayed by immunoblotting. CLL cells were transfected with either siBTK or scrambled control siRNAs (N = 2). Amounts of BTK were analyzed after 4 days of transfection. (C) Efficiency of BTK knock-down assayed by flow cytometry (N = 8). Amounts of total BTK were analyzed with anti-BTK antibody after 4 days of transfection. (D) Mean fluorescence intensity (MFI) of total BTK were plotted for unmutated (N = 4) and mutated CLL patients (N = 4). (E) Proliferative responses of siBTK- and scrambled RNA-transfected UM- and M-CLL were measured by 7-AAD/BrdU incorporation after 8 days of transfection (n = 8). (F) Proliferative responses were analyzed with Paired t test to compare unmutated and mutated CLL subgroups. Scr, scrambled control siRNAs. siBTK, siRNA against BTK. P-values are indicated.