Figure 5

AZD1480 induces G2/M cell cycle arrest by inhibition of Aurora A in HL cell lines. (a) Cells were incubated with AZD1480 (1 or 5 μm) for 24 h, and the cell cycle was analyzed by flow cytometry. AZD1480 induced an increase in the G2/M fraction only when a high concentration (5 μm) was used. (b) Bar graphs summarizing cell cycle analysis results; each value is the mean of three independent experiments. (c) Baseline expression status of Aurora kinases and histone H3 in HL cell lines. Whole-cell lysates of untreated HL cells were examined by western blotting for Aurora A, Aurora B, histone H3 and p-histone H3 (Ser10). (d) Representative western blot assay showing the effect of treatment with 1 and 5 μm AZD1480 (with or without MG132 20μm) for 3 h on Aurora A, Aurora B and histone H3 phosphorylation (Ser 10) in HL cells. Cells were pretreated with nocodazole 400 ng/ml for 18 h to achieve a mitotic block.