BRCA1/2 mutations and expression: response to platinum chemotherapy in patients with advanced stage epithelial ovarian cancer

Gynecol Oncol. 2012 Jun;125(3):677-82. doi: 10.1016/j.ygyno.2012.03.006. Epub 2012 Mar 8.

Abstract

Objective: Our objective was to determine the rate of BRCA1/2 deficiency in platinum-sensitive and platinum-resistant tumors from a cohort of unselect patients with advanced epithelial ovarian cancer (EOH).

Methods: BRCA1/2 mutation analysis was performed in 29 patients with platinum-sensitive EOC and 24 patients with platinum-resistant disease. Germline DNA was analyzed in mutation carriers when normal tissue was available. BRCA expression was ascertained by quantitative rt-PCR. Associations between BRCA mutation status and expression levels and parameters of platinum response were analyzed.

Results: Fifteen of 53 (28.3%) EOC tumors had BRCA1/2 mutations. Twelve mutations were in BRCA1, while 3 involved BRCA2. Of the 12 mutation-carriers with normal tissue available for DNA analyses, 33.3% of the mutations were found to be somatic. Three mutations were novel. The majority of BRCA mutations (73%) were identified in patients with platinum-sensitive disease. In total, 38% of platinum-sensitive tumors were found to have a BRCA mutation, compared to 17% of the platinum-resistant patients. A statistical trend toward platinum-sensitive disease was seen in BRCA mutation carriers (p=0.079). Nineteen (36%) study patients had some form of BRCA deficiency, and these patients were less likely to have platinum-resistant tumors (OR=0.29; p value=0.048).

Conclusions: BRCA mutations occurred more frequently in platinum-sensitive EOC than platinum-resistant disease. The high overall frequency of BRCA deficiency in EOC underscores the importance of tumor profiling as therapies targeting the DNA repair pathway are being investigated.

MeSH terms

  • Adult
  • Aged
  • BRCA1 Protein / biosynthesis
  • BRCA1 Protein / deficiency
  • BRCA1 Protein / genetics
  • BRCA2 Protein / biosynthesis
  • BRCA2 Protein / deficiency
  • BRCA2 Protein / genetics
  • Carcinoma, Ovarian Epithelial
  • Disease-Free Survival
  • Drug Resistance, Neoplasm
  • Female
  • Gene Expression
  • Genes, BRCA1*
  • Genes, BRCA2*
  • Germ-Line Mutation*
  • Humans
  • Middle Aged
  • Neoplasm Staging
  • Neoplasms, Glandular and Epithelial / drug therapy*
  • Neoplasms, Glandular and Epithelial / genetics*
  • Neoplasms, Glandular and Epithelial / metabolism
  • Neoplasms, Glandular and Epithelial / pathology
  • Organoplatinum Compounds / therapeutic use*
  • Ovarian Neoplasms / drug therapy*
  • Ovarian Neoplasms / genetics*
  • Ovarian Neoplasms / metabolism
  • Ovarian Neoplasms / pathology

Substances

  • BRCA1 Protein
  • BRCA1 protein, human
  • BRCA2 Protein
  • BRCA2 protein, human
  • Organoplatinum Compounds