13q14 deletions in CLL involve cooperating tumor suppressors

Blood. 2010 May 13;115(19):3916-22. doi: 10.1182/blood-2009-10-249367. Epub 2010 Jan 13.

Abstract

B-cell chronic lymphocytic leukemia (CLL) is the most common human leukemia. 13q14 deletions are most common chromosomal alterations in CLL. We previously reported that miR-15/16 is a target of 13q14 deletions and plays a tumor suppressor role by targeting BCL2. Because DLEU7 is located near miR-15/16 and is also positioned within a minimal deleted region, we investigated whether DLEU7 could also play a tumor suppressor role. Recent studies of transgenic mouse models demonstrated the importance of the nuclear factor-kappaB (NF-kappaB) pathway in CLL. To examine the possible role of DLEU7 in CLL, we investigated the effect of DLEU7 expression on NF-kappaB and nuclear factor of activated T cells (NFAT) activity. We found that DLEU7 functions as a potent NF-kappaB and NFAT inhibitor by physically interacting and inhibiting TACI and BCMA, members of the tumor necrosis factor (TNF) receptor family involved in B-CLL. In addition, DLEU7 expression in A549 lung cancer cells resulted in a decrease in S phase and increased apoptosis. The results suggest that loss of DLEU7 may cooperate with the loss of miR-15/16 in the pathogenesis of CLL.

Publication types

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

MeSH terms

  • Apoptosis
  • B-Cell Maturation Antigen / genetics
  • B-Cell Maturation Antigen / metabolism
  • Blotting, Western
  • Chromosomes, Human, Pair 13 / genetics*
  • Fluorescent Antibody Technique
  • Genes, Tumor Suppressor*
  • Humans
  • Immunoprecipitation
  • Leukemia, Lymphocytic, Chronic, B-Cell / genetics*
  • Leukemia, Lymphocytic, Chronic, B-Cell / metabolism
  • Leukemia, Lymphocytic, Chronic, B-Cell / pathology
  • Luciferases / metabolism
  • MicroRNAs / physiology
  • NF-kappa B / genetics
  • NF-kappa B / metabolism
  • NFATC Transcription Factors / metabolism
  • Neoplasm Proteins
  • S Phase
  • Sequence Deletion*
  • Transfection
  • Transmembrane Activator and CAML Interactor Protein / genetics
  • Transmembrane Activator and CAML Interactor Protein / metabolism
  • Tumor Suppressor Proteins / genetics
  • Tumor Suppressor Proteins / metabolism

Substances

  • B-Cell Maturation Antigen
  • DLEU7 protein, human
  • MIRN16 microRNA, human
  • MicroRNAs
  • NF-kappa B
  • NFATC Transcription Factors
  • Neoplasm Proteins
  • TNFRSF13B protein, human
  • TNFRSF17 protein, human
  • Transmembrane Activator and CAML Interactor Protein
  • Tumor Suppressor Proteins
  • Luciferases