RUNX1, also known as acute myeloid leukaemia 1 protein (AML1), is a member of the core-binding factor family of transcription factors. It is essential for definitive hematopoiesis in vertebrates and modulates cell proliferation, differentiation, and survival in multiple systems, being involved in diverse signalling pathways [1,2].

RUNX1 is frequently mutated in various hematological malignancies. Germline mutations cause familial platelet disorder with associated myeloid malignancies, while somatic mutations and chromosomal rearrangements are seen in myelodysplastic syndrome and leukemias [1]. In acute myeloid leukemia (AML), the t(8;21) translocation involving RUNX1 leads to a fusion protein that disrupts normal hematopoietic differentiation [3]. Loss-of-function studies in primary human hematopoietic cells showed that RUNX1 loss decreased proliferative capacity but upregulated the IL-3 receptor, rendering cells sensitive to JAK inhibitors, potentially offering a treatment strategy for RUNX1-mutant leukemias [4].

In conclusion, RUNX1 is crucial for normal hematopoiesis and its dysregulation contributes significantly to hematological malignancies. Studies, including loss-of-function experiments, have revealed its role in leukemogenesis, offering potential therapeutic targets for treating related blood cancers.