PHA-739358 reduces phosphorylation of histone H3 at Ser10. K562 cells were exposed to 5 μM PHA-739358 or 5 μM IM for 2 hours. Flow cytometric analysis of cells double stained with specific phospho-H3-(Ser10) antibody and propidium iodide (DNA content) was performed. The gates indicate phospho-histone H3-(Ser10)-positive cells in untreated control cells (A), IM-treated cells (B), or cells exposed to PHA-739358 (C).