Sustained expression of microRNA-155 in hematopoietic stem cells causes a myeloproliferative disorder

Mammalian microRNAs are emerging as key regulators of the development and function of the immune system. Here, we report a strong but transient induction of miR-155 in mouse bone marrow after injection of bacterial lipopolysaccharide (LPS) correlated with granulocyte/monocyte (GM) expansion. Demonstrating the sufficiency of miR-155 to drive GM expansion, enforced expression in mouse bone marrow cells caused GM proliferation in a manner reminiscent of LPS treatment. However, the miR-155-induced GM populations displayed pathological features characteristic of myeloid neoplasia. Of possible relevance to human disease, miR-155 was found to be overexpressed in the bone marrow of patients with certain subtypes of…

• HH
  Howard Hughes Medical Institute
• CR
  Cancer Research Institute
• AS
  American Society of Hematology
• CI
  California Institute of Technology
• NI
  National Institutes of Health