ASXL2 is essential for haematopoiesis and acts as a haploinsufficient tumour suppressor in leukemia

Nat Commun. 2017 May 18;8:15429. doi: 10.1038/ncomms15429.


Additional sex combs-like (ASXL) proteins are mammalian homologues of additional sex combs (Asx), a regulator of trithorax and polycomb function in Drosophila. While there has been great interest in ASXL1 due to its frequent mutation in leukemia, little is known about its paralog ASXL2, which is frequently mutated in acute myeloid leukemia patients bearing the RUNX1-RUNX1T1 (AML1-ETO) fusion. Here we report that ASXL2 is required for normal haematopoiesis with distinct, non-overlapping effects from ASXL1 and acts as a haploinsufficient tumour suppressor. While Asxl2 was required for normal haematopoietic stem cell self-renewal, Asxl2 loss promoted AML1-ETO leukemogenesis. Moreover, ASXL2 target genes strongly overlapped with those of RUNX1 and AML1-ETO and ASXL2 loss was associated with increased chromatin accessibility at putative enhancers of key leukemogenic loci. These data reveal that Asxl2 is a critical regulator of haematopoiesis and mediates transcriptional effects that promote leukemogenesis driven by AML1-ETO.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Bone Marrow Transplantation
  • Core Binding Factor Alpha 2 Subunit / genetics*
  • Core Binding Factor Alpha 2 Subunit / metabolism
  • Disease Models, Animal
  • Gene Expression Regulation, Leukemic*
  • Haploinsufficiency
  • Hematopoiesis / genetics
  • Hematopoietic Stem Cells / cytology
  • Hematopoietic Stem Cells / metabolism
  • Humans
  • Integrases / genetics
  • Integrases / metabolism
  • Leukemia, Myeloid, Acute / genetics*
  • Leukemia, Myeloid, Acute / metabolism
  • Leukemia, Myeloid, Acute / pathology
  • Mice
  • Mice, Knockout
  • Myxovirus Resistance Proteins / genetics
  • Myxovirus Resistance Proteins / metabolism
  • Oncogene Proteins, Fusion / genetics*
  • Oncogene Proteins, Fusion / metabolism
  • Repressor Proteins / deficiency
  • Repressor Proteins / genetics*
  • Signal Transduction
  • Survival Analysis


  • AML1-ETO fusion protein, mouse
  • ASXL2 protein, mouse
  • Asxl1 protein, mouse
  • Core Binding Factor Alpha 2 Subunit
  • Mx1 protein, mouse
  • Myxovirus Resistance Proteins
  • Oncogene Proteins, Fusion
  • Repressor Proteins
  • Runx1 protein, mouse
  • Cre recombinase
  • Integrases