Linking GATA2 to Myeloid Dysplasia and Complex Cytogenetics in Adult Myelodysplastic Neoplasm and Acute Myeloid Leukemia.

GATA Binding Protein 2 (GATA2) is a conserved zinc finger transcription factor that regulates the emergence and maintenance of complex genetic programs driving development and function of hematopoietic stem and progenitor cells (HSPCs). Patients born with monoallelic GATA2 mutations develop myelodysplastic neoplasm (MDS) and acute myeloid leukemia (AML) while acquired GATA2 mutations are reported in 3-5% of sporadic AML cases. The mechanisms by which aberrant GATA2 activity promotes MDS and AML are incompletely understood. Efforts to understand GATA2 in basic biology and disease will be facilitated by the development of broadly efficacious antibodies recognizing physiologic levels of GATA2 in diverse tissue types and assays. Here, we purified a polyclonal anti-GATA2 antibody and generated multiple highly specific anti-GATA2 monoclonal antibodies, optimized them for immunohistochemistry (IHC) on patient bone marrow biopsies, and analyzed GATA2 expression in adults with healthy bone marrow, MDS, and acute leukemia. In healthy bone marrow, GATA2 was detected in mast cells, subsets of CD34+ HSPCs, E-cadherin+ erythroid progenitors, and megakaryocytes. In MDS, GATA2 expression tracks with bone marrow blast percentage, positively correlates with myeloid dysplasia and complex cytogenetics, and is a non-independent negative predictor of overall survival. In acute leukemia, percent GATA2+ blasts closely associates with myeloid lineage, while a subset of lymphoblastic and undifferentiated leukemias with myeloid features also express GATA2. However, percent of GATA2+ blasts in AML is highly variable. Elevated GATA2 expression in AML blasts correlates with peripheral neutropenia and complex AML cytogenetics but unlike in MDS does not predict survival.