학술논문

ASXL2 regulates hematopoiesis in mice and its deficiency promotes myeloid expansion
Document Type
article
Source
Haematologica. 103(12)
Subject
Rare Diseases
Human Genome
Childhood Leukemia
Cancer
Pediatric
Hematology
Pediatric Cancer
Genetics
2.1 Biological and endogenous factors
Aetiology
Acute Disease
Animals
Cell Differentiation
Cell Proliferation
Gene Expression Profiling
Hematopoiesis
Humans
Leukemia
Myeloid
Mice
129 Strain
Mice
Inbred C57BL
Mice
Knockout
Myeloid Cells
Myelopoiesis
Repressor Proteins
Immunology
Language
Abstract
Chromosomal translocation t(8;21)(q22;q22) which leads to the generation of oncogenic RUNX1-RUNX1T1 (AML1-ETO) fusion is observed in approximately 10% of acute myelogenous leukemia (AML). To identify somatic mutations that co-operate with t(8;21)-driven leukemia, we performed whole and targeted exome sequencing of an Asian cohort at diagnosis and relapse. We identified high frequency of truncating alterations in ASXL2 along with recurrent mutations of KIT, TET2, MGA, FLT3, and DHX15 in this subtype of AML. To investigate in depth the role of ASXL2 in normal hematopoiesis, we utilized a mouse model of ASXL2 deficiency. Loss of ASXL2 caused progressive hematopoietic defects characterized by myeloid hyperplasia, splenomegaly, extramedullary hematopoiesis, and poor reconstitution ability in transplantation models. Parallel analyses of young and >1-year old Asxl2-deficient mice revealed age-dependent perturbations affecting, not only myeloid and erythroid differentiation, but also maturation of lymphoid cells. Overall, these findings establish a critical role for ASXL2 in maintaining steady state hematopoiesis, and provide insights into how its loss primes the expansion of myeloid cells.