In preclinical models, for example, an LSD1 inhibitor synergistically reduced AML cell viability in combination with cytarabine (Ara-C), a DNA-damaging agent widely used with daunorubicin as standard care for AML.10 LSD1 inhibitors also showed synergistic antileukemic effects in combination with an HDAC inhibitor or all-trans retinoic acid in AML cell lines.12, 13. This evidence concerns the gene HDAC9 and acute myeloid leukemia.