(A) Human T-ALL cell lines were treated with DMSO, 300 nM ABT-263, 500 nM AZD8055 or a combination of 300 nM ABT-263 and 500 nM AZD8055 for 48h, after which cells were stained with propidium iodide and Annexin-V. Apoptosis was measured by FACS analysis as percentage of cells that are Annexin-V positive. The experiment was done in triplicate and the percentage apoptosis values are shown for each treatment with mean ± SD. (B) Primary T-ALL cells from six patients were treated with DMSO, 1 μM ABT-263, 500 nM AZD8055 or a combination of 1 μM ABT-263 and 500 nM AZD8055 for 3days, after which cells were stained with propidium iodide and Annexin-V. Apoptosis was measured by FACS analysis as percentage of Annexin-V positive cells. The experiment was done in triplicate and the percentage apoptosis values are shown for each treatment with mean ± SD.