RUNX1 is generally considered a tumor suppressor in myeloid neoplasms. Inactivating RUNX1 mutations have frequently been found in patients with myelodysplastic syndrome (MDS) and cytogenetically normal acute myeloid leukemia (AML). However, no somatic RUNX1 alteration was found in AMLs with leukemogenic fusion proteins, such as core-binding factor (CBF) leukemia and MLL fusion leukemia, raising the possibility that RUNX1 could actually promote the growth of these leukemia cells. Using normal human cord blood cells and those expressing leukemogenic fusion proteins, we discovered a dual role of RUNX1 in myeloid leukemogenesis. RUNX1 overexpression inhibited the growth of normal cord blood cells by inducing myeloid differentiation, whereas a certain level of RUNX1 activity was required for the growth of AML1-ETO and MLL-AF9 cells. Using a mouse genetic model, we also showed that the combined loss of
Susumu Goyama, Janet Schibler, Lea Cunningham, Yue Zhang, Yalan Rao, Nahoko Nishimoto, Masahiro Nakagawa, Andre Olsson, Mark Wunderlich, Kevin A. Link, Benjamin Mizukawa, H. Leighton Grimes, Mineo Kurokawa, P. Paul Liu, Gang Huang, James C. Mulloy
RUNX1 inhibits the growth of human CB cells by inducing myeloid maturation.