NOTCH and NF-κB interplay in chronic lymphocytic leukemia is independent of genetic lesion

Int J Hematol. 2013 Aug;98(2):153-7. doi: 10.1007/s12185-013-1368-y. Epub 2013 May 21.

Abstract

The NOTCH and nuclear factor kappa B (NF-κB) pathways are both constitutively activated in Chronic Lymphocytic Leukemia (CLL). We first described the NOTCH1 PEST domain mutation in a CLL subgroup, but the activation of the NOTCH pathway in NOTCH1-unmutated cases remains unexplained. Here, we investigated whether genetic lesions in the NF-κB/NOTCH loop might support the NOTCH activation status by sequencing negative (TNFAIP3/A20) and positive (TRAF2, TRAF5, TNFRSF11A/RANK, MAP3K7/TAK1, and CARD11) regulators of NF-κB together with NF-κB targets on the NOTCH pathway, the NOTCH ligands Jagged1 and Jagged2, in CLL patients. The sequence analysis revealed four missense mutations for A20, TRAF2, TRAF5 and RANK1 genes, all causing a change in amino acid group from polar to non-polar, but functional domains were not involved. Specific predictive software analyses confirmed that the amino acid changes have a low-functional impact on the protein. Our results show that in CLL, NF-κB regulators and Jagged are both unmutated, suggesting that the Jagged-mediated interplay between NF-κB and NOTCH is independent of genetic lesions.

Publication types

  • Clinical Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Amino Acid Substitution
  • Female
  • Humans
  • Leukemia, Lymphocytic, Chronic, B-Cell* / genetics
  • Leukemia, Lymphocytic, Chronic, B-Cell* / metabolism
  • Leukemia, Lymphocytic, Chronic, B-Cell* / pathology
  • Male
  • Middle Aged
  • Mutation, Missense*
  • NF-kappa B* / genetics
  • NF-kappa B* / metabolism
  • Neoplasm Proteins* / genetics
  • Neoplasm Proteins* / metabolism
  • Protein Structure, Tertiary
  • Receptors, Notch* / genetics
  • Receptors, Notch* / metabolism

Substances

  • NF-kappa B
  • Neoplasm Proteins
  • Receptors, Notch