RUNX1 and acute myeloid leukemia: In support of this view, the expression of RUNX1-ETO, a related RUNX1 gene fusion that occurs in acute myeloid leukemias, also upregulates MDM2 and thereby represses p53 signaling in hematopoietic stem cells.45 Moreover, treatment of these transduced cells with Nutlin-3 reversed the observed increased proliferation and self-renewal.