PHA-739358 induces apoptosis, accumulation of cells with more than or equal to 4N DNA content, and G2/M arrest in BCR-ABL–positive BaF3 cells. BaF3, BaF3-p210, BaF3-M351T, and BaF3-T315I cells were exposed for 48 hours to indicated concentrations of PHA-739358. Cell-cycle analysis and apoptotic fraction of propidium iodide-stained cells were assessed by flow cytometry. Numbers on the plots are means (± SD) of the apoptotic fraction.