Rescue of cellular viability and AML1-ETO gene signature with chemical antagonists. (A) Kasumi-1 cells treated with methotrexate or methylprednisolone. Rescue was performed with either 1 μM leucovorin or 1 μM RU486. Cellular viability was assessed at 72 hours with an ATP-based assay and plotted as a ratio relative to control cells. Samples were evaluated in replicates of 7. Leucovorin rescued only methotrexate, while RU486 rescued only methylprednisolone. (B) Weighted summed score for the AML1-ETO signature upon treatment of Kasumi-1 cells with 160 nM methotrexate (MTX) or 160 nM methylprednisolone (MPD) for 72 hours. Chemical rescue was performed with cotreatment of 1 μM leucovorin or 1 μM RU486 as indicated.