Figure 4

Combination of I-BET762 with ABT-263 increases apoptosis in rituximab/chemoresistant B-cell lymphomas overexpressing Bcl-2. (a and b) Eμ-myc/Bcl-2 and human U2932-4RH lymphomas were treated with indicated concentrations of ABT-263 or I-BET762 for 48 and 240 h, respectively. Apoptosis was assessed by flow cytometry analysis of TMRE, surface exposure of phosphotidylserine (annexin V staining) and cell-cycle analysis. Each point represents the mean ±S.E. value of three individual experiments, *P<0.05. (c) Western blot analysis on whole-cell lysates prepared from the Eμ-myc/Bcl-2 and human U2932-4RH lymphomas treated for 24 and 72 h, respectively, with the single agents or in combination. The expression of indicated proteins was detected with specific antibodies and loading normalization was confirmed by GAPDH probing