Pretreatment with EPZ004777 profoundly decreased the in vivo spleen-colony-forming ability of MLL-AF10 or CALM-AF10 transformed bone marrow cells.     ///    Targeted disruption of Dot1l using a conditional knockout mouse model abolished in vitro transformation of murine bone marrow cells and in vivo initiation and maintenance of MLL-AF10 or CALM-AF10 leukemia.     ///    Abrogation of MLL-AF10 and CALM-AF10-mediated transformation through genetic inactivation or pharmacological inhibition of the H3K79 methyltransferase Dot1l..     ///    "Here, we demonstrate that MLL-AF10 and CALM-AF10-mediated transformation is dependent on the H3K79 methyltransferase Dot1l using genetic and pharmacological approaches in mouse models. "    ///    "The treatment of MLL-AF10 and CALM-AF10 transformed cells with EPZ004777, a specific small-molecule inhibitor of Dot1l, suppressed expression of leukemogenic genes such as Hoxa cluster genes and Meis1, and selectively impaired proliferation of MLL-AF10 and CALM-AF10 transformed cells. "