Fig. 4.

Mechanisms of self‐renewal. (A) Self‐renewal in normal hematopoiesis and leukemogenesis. One HSC can reconstitute the hematopoietic system, whereas 50 MPPs cannot achieve the same repopulation. The transition from HSC to MPP is a point‐of‐no return where cells lose their self‐renewing ability. Leukemic oncogenes such as MLL fusions and MOZ fusions confer self‐renewing ability to committed progenitors and induce leukemia. HSC, hematopoietic stem cell; MPP, multipotent progenitor; CMP, common myeloid progenitor; GMP, granulocyte/macrophage progenitor. (B) Self‐renewal mechanism mediated by the MLL/MOZ/AEP‐mediated transcriptional activation system. After each cell division, the MLL‐MOZ and AEP complexes activate CpG‐rich promoters that were previously transcribed in the mother cell to promote self‐renewal.