HUNTSVILLE - A new study by a national network of genetic laboratories including Huntsville's HudsonAlpha Institute for Biotechnology is being called a step toward individualized treatment for women fighting the most deadly form of ovarian cancer.
The study, reported in the June 30 issue of the scientific journal Nature, created the broadest and clearest portrait yet of serous adenocarcinoma, the most prevalent form of ovarian cancer responsible for 86 percent of all ovarian cancer deaths.
By identifying four specific "sub-types" of this cancer, the study will help doctors predict the response of patients to specific drugs, according to HudsonAlpha's Dr. Devin Absher. Absher is one of the authors of the study.
"The immediate effect will be to change the treatment regimen for some patients," Absher said.
Among the findings was that mutations in a single gene, TP53, were present in more than 96 percent of cases of serous adenocarcinoma.
Similar genetic analysis of breast cancer has led to better-targeted treatment of that disease, and Absher said some of the same genes are active in both hormonally regulated cancers.
Mutations in two genes, BRCA1 and BRCA2, are already associated with some forms of breast cancer, and the new study found approximately 21 percent of the ovarian tumors analyzed also had mutations in these genes.
In this case, the mutations were good. Analysis found that patients with mutated BRCA1 or BRCA2 genes have better survival odds than those without the mutations.
"It's probably like that because they are key regulators of cell growth," Absher said, "It's likely they play a specific role in hormonally regulated cancers."
Absher also speculated that the genes may be involved in even more forms of cancer. "It makes them good drug targets," Absher said.
The study followed a new model first used last year in studying a kind of brain tumor. Scientists at different institutes, all members of the Cancer Genome Atlas Research Network, performed different tests on samples of the same tumors.
"It's the same set of individuals with a very highly controlled set of clinical data -- what drugs have they been on, how have they progressed, how long have they survived, recurrence after surgery, all sorts of data like that ," Absher said.
HudsonAlpha's role was what is called "copy number analysis" or looking at what parts of DNA are missing or multiplied in the tumor samples.
"First, we learned that up to 50 percent of ovarian tumors may be responsive to a type of drug called PARP inhibitors, which are already approved and ready for use," said Dr. Chris Gunter, Ph.D, director of research affairs at HudsonAlpha. "Second, HudsonAlpha's research ... suggested new regions to be investigated as potential drug targets in ovarian cancer overall, as well as in specific subtypes of ovarian cancer."
Gunter confirmed this is a step closer to individualized treatments for women fighting the disease.
"It is exciting to be part of such a large study...," HudsonAlpha President Dr. Rick Myers said Tuesday. "We now know more about ovarian cancer than ever before. This voluminous data set that HudsonAlpha has helped to compile is an invaluable resource for basic and clinical researchers who are working to improve methods for diagnosing and treating ovarian cancer."
The study was coordinated by the National Cancer Institute and the National Human Genome Research Institute, both part of the National Institutes of Health.
Similar studies will be conducted beginning next year on other kinds of cancer tumors, Absher said, but HudsonAlpha is not scheduled to participate in the next round. The institute is involved in other research projects studying breast, prostate and pancreatic cancer.