Researchers from The Cancer Genome Atlas Research Network have completed what is being called the largest cancer genome study to date, according to a press release from the National Cancer Institute. The study, recently published in Nature, is a detailed analysis of the genomic changes in ovarian cancer — ovarian serous adenocarcinoma tumors from 500 patients were examined by the consortium's researchers, who performed whole-exome sequencing on 316 tumors and other genomic characterizations all 500 specimens, NCI says. Among the specific discoveries made by the TCGA team is the confirmation that mutations in the TP53 genes that disrupt the gene's ability to suppress growth of ovarian cells are present in more than 96 percent of ovarian tumors, the press release says. "TCGA researchers also established how sets of genes are expressed in a fashion that can predict patient survival — identifying patterns for 108 genes associated with poor survival and 85 genes associated with better survival," it adds. "Patients whose tumors had a gene-expression signature associated with poor survival lived for a period that was 23 percent shorter than patients whose tumors did not have such a signature." In light of this new information, the researchers also looked for existing drugs that might help treat ovarian cancer, and found several FDA-approved or experimental compounds that could affect a total of 68 genes implicated in ovarian cancer. "The investigators noted that one type of drug, a PARP inhibitor, might be able to counteract the DNA repair gene observed in half of the ovarian tumors studied," NCI says. "While researchers have known that these drugs could be effective against the disease, this study revealed that 50 percent of tumors might be responsive to drugs that exploit the genetic instability of the tumors and induce the cancer cells to die."
Analyzing Ovarian Cancer
Jun 30, 2011