Inflammation-mediated notch signaling skews fanconi anemia hematopoietic stem cell differentiation

J Immunol. 2013 Sep 1;191(5):2806-17. doi: 10.4049/jimmunol.1203474. Epub 2013 Aug 7.

Abstract

Hematopoietic stem cells (HSCs) can either self-renew or differentiate into various types of cells of the blood lineage. Signaling pathways that regulate this choice of self-renewal versus differentiation are currently under extensive investigation. In this study, we report that deregulation of Notch signaling skews HSC differentiation in mouse models of Fanconi anemia (FA), a genetic disorder associated with bone marrow failure and progression to leukemia and other cancers. In mice expressing a transgenic Notch reporter, deletion of the Fanca or Fancc gene enhances Notch signaling in multipotential progenitors (MPPs), which is correlated with decreased phenotypic long-term HSCs and increased formation of MPP1 progenitors. Furthermore, we found an inverse correlation between Notch signaling and self-renewal capacity in FA hematopoietic stem and progenitor cells. Significantly, FA deficiency in MPPs deregulates a complex network of genes in the Notch and canonical NF-κB pathways. Genetic ablation or pharmacologic inhibition of NF-κB reduces Notch signaling in FA MPPs to near wild type level, and blocking either NF-κB or Notch signaling partially restores FA HSC quiescence and self-renewal capacity. These results suggest a functional crosstalk between Notch signaling and NF-κB pathway in regulation of HSC differentiation.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cell Differentiation / physiology*
  • Disease Models, Animal
  • Fanconi Anemia / metabolism*
  • Flow Cytometry
  • Hematopoietic Stem Cells / metabolism*
  • Immunoblotting
  • Inflammation / metabolism
  • Mice
  • Mice, Knockout
  • NF-kappa B / metabolism*
  • Oligonucleotide Array Sequence Analysis
  • Real-Time Polymerase Chain Reaction
  • Receptor Cross-Talk / physiology
  • Receptors, Notch / metabolism*
  • Signal Transduction / physiology*

Substances

  • NF-kappa B
  • Receptors, Notch