MAFB and leukemia: In agreement with previous reports [15], we show that depletion of MYB reverses the leukaemia-associated cellular phenotypes in MLL-rearranged AML, which is accompanied by de-repression of MAFB. However, we find that AML with complex karyotypic lesions does not undergo the conventional transcriptional and morphological alterations that are associated with MYB suppression.