Figure 5.

ARQ531 treatment results in oncogenic program dysregulation in acute myeloid leukemia cells. (A) Western blot analysis of cells treated with ARQ531 (1 mM) after the indicated hours. Time-dependent effects demonstrate early inhibition of BTK activity and MYC downregulation followed by a reduction of MYB with associated PARP and caspase 3 cleavage. (B) Treatment of HL60 cells with BET bromodomain inhibitor JQ1 (400 nM), ibrutinib (30 mM) or their combination, which resulted in a synergistic effect. Bars and error bars are means and standard deviation of three independent experiments. ***P<0.001 (relative to dimethylsulfoxide controls), one-sample t-test. (C) Western blot showing that ibrutinib, JQ1, and their combination result in appearance of apoptotic features, including caspase 3 and PARP cleavage in HL60 cells.