Aurora B kinase selective inhibitor, AZD1152-HQPA, shows antiproliferative effects in HCC cells. (A) Concentration-dependent inhibitory effects of AZD1152-HQPA on cell viability in Huh-7 and Hep3B cell lines. Cells were treated with AZD1152-HQPA at 1, 5, 25, and 125 nM in 10% FBS-supplemented medium for 72 hours; cell viability was determined by trypan blue assay. Columns: means; bars: SD (n = 3). §, p < 0.05; *, p < 0.01 (compared with untreated controls). The changes in cell counts and morphologic features are shown in the lower panels (magnification, × 100). (B) Huh-7 and Hep3B cells were treated with AZD1152-HQPA for 24 hours. The cell lysates were then immunoblotted. Histone H3 (Ser10) phosphorylation, the key substrate of Aurora B signaling, was downregulated in a concentration-dependent manner. Aurora A (T288) phosphorylation, the key substrate of Aurora A signaling, was not repressed by AZD1152-HQPA treatments.