Mitotic defects in XRCC3 variants T241M and D213N and their relation to cancer susceptibility

Hum Mol Genet. 2006 Apr 1;15(7):1217-24. doi: 10.1093/hmg/ddl037. Epub 2006 Feb 27.

Abstract

The XRCC3 variant T241M, but not D213N, has been reported to be associated with an increased risk of some cancers. XRCC3 is one out of five RAD51 paralogues and is involved in homologous recombination, as are the BRCA1 and BRCA2 proteins. However, in contrast to mutations in BRCA1 and BRCA2, the XRCC3(T241M) protein is proficient in homologous recombination and reverts sensitivity to mitomycin C found in XRCC3-deficient cells, whereas XRCC3(D213N) is defective in homologous recombination. Here, we report that both the XRCC3 D213N and T241M alleles are associated with an increase in centrosome number and binucleated cells. However, only the D213N allele gives an increase in spontaneous levels of apoptosis. We suggest that the inability of XRCC3 T241M to apoptotically eliminate aberrant cells with mitotic defects could increase cancer susceptibility in individuals carrying this variant. In contrast, cells carrying the XRCC3 D213N variant are able to eliminate aberrant cells by apoptosis, and consistent with this observation, this variant does not seem to be associated with cancer susceptibility.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Alleles
  • Animals
  • Apoptosis / genetics
  • CHO Cells
  • Cell Line
  • Cells, Cultured
  • Centrosome / metabolism
  • Cricetinae
  • DNA-Binding Proteins / genetics*
  • DNA-Binding Proteins / metabolism
  • Disease Susceptibility / embryology
  • Disease Susceptibility / metabolism*
  • Fluorescent Antibody Technique
  • Genetic Variation
  • Humans
  • Mitosis* / genetics
  • Neoplasms / genetics*
  • Neoplasms / metabolism

Substances

  • DNA-Binding Proteins
  • X-ray repair cross complementing protein 3