MECOM and acute myeloid leukemia: In addition, CEBPA expression is suppressed by the leukaemogenic fusion proteins AML1-ETO, AML1-MDS1-EVI1, or CBFB-SMMHC in AML patients bearing the chromosomal rearrangements t(8;21), t(3;21) or inv(16) respectively (Pabst et al, 2001a; Helbling et al, 2004, 2005).