Furthermore, other key hematopoietic regulators have notable roles in RUNX1/ETO driven leukemia—interaction with the ETS factors ERG and FLI1 influences targeting of RUNX1/ETO to chromatin as part of the AETFC complex [13,59], whilst the function of the myeloid-specific PU.1 is impaired by RUNX1/ETO, due to displacement of the AP-1 factor c-JUN [54,60]. This evidence concerns the gene JUN and leukemia.