The reduced dependency of the leukaemia phenotype on MYB levels in complex karyotype AML cells, represented in our study by FUJIOKA and KG1A cells, is mirrored by a smaller number of changes in gene expression upon MYB depletion, including no change in the levels of MAFB or known MYB targets such as GFI1, FLT3, and PIM1, which are seen to be affected in the MLL-driven AML cells. The gene discussed is PIM1; the disease is acute myeloid leukemia.