Combination of 56 with inhibitors of AURKB but not MAP2K1/2 or ABL1 reduces cell viability. HEK293T cells were treated with (A) DMSO, 56 (30 nM, 90 nM, and 270 nM), AZD-1152-HQPA (40 nM) without and with 56, or 5 (300 nM); (B) DMSO, 56 (30 nM, 90 nM, and 270 nM), MLN-8054 (40 nM) without and with 56, or 5 (300 nM); (C) DMSO, 56 (30 nM, 90 nM, and 270 nM), MK-5108 (3 μM) without and with 56, or 5 (300 nM); (D) DMSO, 56 (90 nM), TAK-733 (10 μM) without and with 56, or 5 (300 nM); (E) DMSO, 56 (90 nM), AS-703026 (10 μM) without and with 56, or 5 (300 nM); and (F) DMSO, 56 (90 nM), Imatinib (3 μM) without and with 56, or Dasatinib (1 μM) without and with 56. Cells were treated for 48 hrs, fixed, stained, counted, and cell number plotted as a percentage of untreated wells. Error bars indicate standard deviation (n = 4-16, ****,p<0.0001; ***, 0.0001<p<0.001; **, 0.00<p<0.01; *, 0.01<p<0.05; NS, p>0.05).