Based on these data, we developed orthogonal approaches that revealed that CBFB::MYH11 is primarily cytoplasmic in primary murine hematopoietic cells and primary human CBFB::MYH11 AML cells, and that the fusion protein sequesters RUNX1 in cytoplasmic aggregates, probably reducing the activity of CBF in the nucleus. The gene discussed is CEBPZ; the disease is acute myeloid leukemia.