A KRAS-variant in Ovarian Cancer Acts as a Genetic Marker of Cancer Risk

Cancer Res. 2010 Aug 15;70(16):6509-15. doi: 10.1158/0008-5472.CAN-10-0689. Epub 2010 Jul 20.

Abstract

Ovarian cancer (OC) is the single most deadly form of women's cancer, typically presenting as an advanced disease at diagnosis in part due to a lack of known risk factors or genetic markers of risk. The KRAS oncogene and altered levels of the microRNA (miRNA) let-7 are associated with an increased risk of developing solid tumors. In this study, we investigated a hypothesized association between an increased risk of OC and a variant allele of KRAS at rs61764370, referred to as the KRAS-variant, which disrupts a let-7 miRNA binding site in this oncogene. Specimens obtained were tested for the presence of the KRAS-variant from nonselected OC patients in three independent cohorts, two independent ovarian case-control studies, and OC patients with hereditary breast and ovarian cancer syndrome (HBOC) as well as their family members. Our results indicate that the KRAS-variant is associated with more than 25% of nonselected OC cases. Further, we found that it is a marker for a significant increased risk of developing OC, as confirmed by two independent case-control analyses. Lastly, we determined that the KRAS-variant was present in 61% of HBOC patients without BRCA1 or BRCA2 mutations, previously considered uninformative, as well as in their family members with cancer. Our findings strongly support the hypothesis that the KRAS-variant is a genetic marker for increased risk of developing OC, and they suggest that the KRAS-variant may be a new genetic marker of cancer risk for HBOC families without other known genetic abnormalities.

Publication types

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

MeSH terms

  • Adult
  • Aged
  • Biomarkers, Tumor / genetics*
  • Breast Neoplasms / genetics
  • Case-Control Studies
  • Female
  • Genes, ras*
  • Genetic Markers
  • Genetic Predisposition to Disease
  • Genetic Variation
  • Humans
  • Middle Aged
  • Ovarian Neoplasms / genetics*

Substances

  • Biomarkers, Tumor
  • Genetic Markers