To assess for specific cellular functions required for fusion-oncogene driven AML and to identify oncogenic cellular functions with relevance for KMT2A-r leukemia, we performed global proteome profiling on either KMT2A::MLLT3 (MLL-AF9; MA9) or AML1-ETO9a (AE) AMLs generated by expression of the fusion oncogenes in murine HSPCs (Lineage− Sca1+ c-Kit+, LSK). The gene discussed is MLLT3; the disease is acute myeloid leukemia.