(A) Bone marrow mononuclear cells harvested from four untreated T-ALL patients were treated with JQ1 at the indicated concentrations for 72 hours, at which point viable cell number was determined by ATP-dependent bioluminescence. (B) Bone marrow mononuclear cells harvested from patient 1 with TALL patients were treated with JQ1 (0.125μM), JAK inhibitor 1 (1 μM), or the combination for 72 hours, after which viable cell number was quantitated by ATP-dependent bioluminescence. (C) Isobologram analysis was performed based on loss of cell viability for 14 different combinations of JQ1 and JAKi. Data points below the line indicate synergistic effects. (D) Mononuclear cells from umbilical cord blood (n=4), or ALL-SIL or DU528 T lymphocytic leukemia cells were treated for 72 hours with JQ1 (0.25 μM) or TKIs (imatinib 0.125 μM or JAKi 0.5 μM), alone or in combination, and viable cell number was quantitated by ATP-dependent bioluminescence.