Bim silencing protects Karpas707 cells from drug-induced apoptosis. (A-B) Silencing of Bim in the Karpas707 cells. (A) Comparison of the Bim expression of the ShScrambled (control) and ShBim Karpas707 cell lines with the use of quantitative RT-PCR analysis. The mean value ± SD of 3 independent experiments is given (*P < .05). (B) Comparison of the Bim expression of the ShScrambled (lane 1) and ShBim (lane 2) Karpas707 cell lines by Western blot analysis. Equivalent amounts of lysates were immunoblotted with anti-Bim and anti-actin to confirm equal loading. One experiment representative of 3 is shown. The numbers below refer to the optical density of the BimEL, BimL, and BimS bands as measured with the NIH1.62 image program. Variation between experiments was below 10%. (C-E) Cells were treated with 10nM bortezomib, 15μM melphalan, and 15nM LBH589 for (C) 24 and (D) 48 hours. Viability was measured by the Celltiter-Glo luminescent cell viability assay. Caspase-3 activity after 24 hours of treatment (E) was measured with the Caspase-Glo 3/7 assay. Experiments were performed 4 times, and the results are given as the percentage of control (untreated) viability or caspase-3 activity (mean value ± SD; *P < .05).