MLLT3 and acute myeloid leukemia: As determined by serial colony-forming assay, Foxm1-CKO BM cells expressing AML1-ETO9a gave rise to increased number of colonies at the first, second, and third plating as compared to control Foxm1fl/fl BM cells expressing AML1-ETO9a (Supplementary Fig. 3), suggesting that Foxm1 plays an oncogenic role in MLL-AF9-induced AML but not AML1-ETO9a-induced AML.