A novel GATA2 distal enhancer mutation results in MonoMAC syndrome in 2 second cousins

Prognostic significance of GATA2 in patients with MDS/AML: a systematic review and meta-analysis

GATA2 deficiency syndrome is a heterogeneous disorder characterized by a high risk of developing myelodysplastic syndrome (MDS)/acute myeloid leukaemia (AML). We conducted a meta-analysis of the literature to explore the prognostic significance of GATA2 mutations in patients diagnosed with MDS/AML, as previous studies have yielded conflicting findings regarding the impact of GATA2 mutations on patient outcomes. We conducted a comprehensive literature search of databases such as PubMed, Embase, the Cochrane Library, and the Web of Science to obtain studies on the prognostic significance of GATA2 mutations in patients with MDS/AML that were published through January 2024. We extracted the hazard ratio (HR) and 95% confidence interval (CI) for overall survival (OS), disease-free survival (DFS), and event-free survival (EFS). The meta-analysis was conducted by choosing either a fixed-effect model or a random-effect model, depending on the variability observed among the studies. A total of 13 cohort studies were included in the final meta-analysis, including 2714 patients with MDS, of whom 644 had GATA2 mutations. The results revealed that GATA2 mutations had an adverse impact on OS (HR = 1.54, 95% CI = 1.08-2.18, P = 0.02) and EFS (HR = 1.32, 95% CI = 1.01-1.72, P = 0.04), but no significant effect on DFS (HR = 1.21, 95% CI = 0.89-1.64, P = 0.23). GATA2 mutations were associated with a significantly shorter OS in MDS patients (HR = 2.56, 95% CI = 1.42-4.06, P = 0.002) but not in AML patients (HR = 1.08, 95% CI = 0.92-1.26, P = 0.37). Our meta-analysis revealed that GATA2 mutations are associated with unfavourable outcomes in patients with MDS/AML. Furthermore, patients harbouring these mutations should be prioritized for aggressive therapeutic interventions.

Pathogenic GATA2 genetic variants utilize an obligate enhancer mechanism to distort a multilineage differentiation program

Mutations in genes encoding transcription factors inactivate or generate ectopic activities to instigate pathogenesis. By disrupting hematopoietic stem/progenitor cells, GATA2 germline variants create a bone marrow failure and leukemia predisposition, GATA2 deficiency syndrome, yet mechanisms underlying the complex phenotypic constellation are unresolved. We used a GATA2-deficient progenitor rescue system to analyze how genetic variation influences GATA2 functions. Pathogenic variants impaired, without abrogating, GATA2-dependent transcriptional regulation. Variants promoted eosinophil and repressed monocytic differentiation without regulating mast cell and erythroid differentiation. While GATA2 and T354M required the DNA-binding C-terminal zinc finger, T354M disproportionately required the N-terminal finger and N terminus. GATA2 and T354M activated a CCAAT/Enhancer Binding Protein-ε (C/EBPε) enhancer, creating a feedforward loop operating with the T-cell Acute Lymphocyte Leukemia-1 (TAL1) transcription factor. Elevating C/EBPε partially normalized hematopoietic defects of GATA2-deficient progenitors. Thus, pathogenic germline variation discriminatively spares or compromises transcription factor attributes, and retaining an obligate enhancer mechanism distorts a multilineage differentiation program.

Linking GATA2 to myeloid dysplasia and complex cytogenetics in adult myelodysplastic neoplasm and acute myeloid leukemia

ABSTRACT

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), whereas acquired GATA2 mutations are reported in 3% to 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 on patient bone marrow bioosy samples, 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-positive erythroid progenitors, and megakaryocytes. In MDS, GATA2 expression correlates with bone marrow blast percentage, positively correlates with myeloid dysplasia and complex cytogenetics, and is a nonindependent negative predictor of overall survival. In acute leukemia, the percent of GATA2+ blasts closely associates with myeloid lineage, whereas a subset of lymphoblastic and undifferentiated leukemias with myeloid features also express GATA2. However, the 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.