Somatic cell mutations and chromosomal abnormalities, including those of RUNX1, are observed in myelodysplastic syndrome, acute myeloid leukemia, acute lymphoblastic leukemia, and chronic myelomonocytic leukemia at a high frequency.
Here we demonstrate that runx1 deletion in mice induces the persistence of MYH10 in platelets, and a similar persistence was observed in platelets of patients with constitutional (familial platelet disorder/acute myeloid leukemia) or acquired (chronic myelomonocytic leukemia) RUNX1 mutations.
RUNX1 mutations are frequent in chronic myelomonocytic leukemia and mutations at the C-terminal region might predict acute myeloid leukemia transformation.
Studies on the regulation of Evi-1 expression in CD34+ cells will elucidate its function in progenitor cells and clarify its possible role in the pathogenesis of JMML.
Overall, our results suggest that the EVI-1 gene may be normally expressed in early hematopoietic progenitor cells and that in JMML patients an expansion of the EVI-1 positive cell population can be revealed within the clonogenic progenitor pool.