Moffitt Cancer Center researchers have helped identify six new regions of the genome that increase the risk of epithelial ovarian cancer.
The collaborative study, which examined DNA from nearly 70,000 women (including 18,000 with ovarian cancer), was published Monday in Nature Genetics.
An estimated 22,000 new cases of ovarian cancer are diagnosed each year in the United States. It is the fifth most common cause of cancer-related death in women, with approximately 14,000 deaths each year and a 5-year survival rate of only 44 percent.
Ovarian cancer has been called the "silent killer" because its symptoms often go unnoticed until the disease is so advanced it is virtually untreatable. Epithelial ovarian cancer originates in the layer of cells that cover the ovary and the entire abdominal cavity. It's the most common ovarian cancer type, accounting for roughly 90 percent of all cases, according to cancercenter.com.
The study is unique in that it includes a combined analysis of two groups of women who had their genetic profiles completed as part of a large international collaboration. The first group included women with and without ovarian cancer who had inherited a mutation in BRCA1 or BRCA2, which are gene mutations already known to increase risk of ovarian cancer.
The women were recruited to 54 studies in 27 countries. The second group included ovarian cancer cases without BRCA mutations and cancer-free controls who were part of the Ovarian Cancer Association Consortium that included 26 individual studies.
DNA was extensively analyzed for genetic changes called single-nucleotide polymorphisms (SNPs). SNPs found on six different regions on chromosomes 1, 4, 6, 9 and 17 are linked to epithelial ovarian cancer.
With this most recent investigation, the number of SNPs that influence ovarian cancer risk has increased to 18. This information can be used to stratify patients according to their risk of developing cancer and enable primary prevention efforts.
“This study gets us closer to the ability to identify women with a 10 percent lifetime risk of ovarian cancer, which is the generally accepted target for clinical intervention to lower risk," said Dr. Thomas Sellers, the center director at Moffitt. "Given that there is no early detection test, most women are diagnosed at late stage and outcomes are less than optimal. Thus, identification of women at high risk to try and prevent the disease is really appealing and an important goal to pursue.”
Seven Moffitt researchers participated in this international study, including Sellers, Catherine M. Phelan, Ph.D., M.D., M.M.S.; Jenny Permuth-Wey, Ph.D.; Alvaro N.A. Monteiro, Ph.D.; Y. Ann Chen, Ph.D.; Hui-Yi Lin, Ph.D.; and Zhihua Chen.
Blood-sugar levels important for pregnancy
If you are planning a pregnancy, it's important to have your blood sugar levels in control before conceiving.
When a woman becomes pregnant, a glucose screening test is done. If those results reveal elevated blood-glucose levels, a glucose tolerance test can help determine if both mom and baby could be at risk.
"If a woman develops gestational diabetes throughout their pregnancy or has diabetes going into a pregnancy, that high blood sugar, if it's not controlled, can lead to complications, both for the mom and the baby," said Dr. Sharon Bergquist, assistant professor of medicine at Emory University.
"For the mom, the biggest risks are that you can have a disease or development of preeclampsia. That's when the blood pressures get very high. You can have a premature delivery, meaning you would have the baby at 37 weeks or earlier. Stillbirths become a concern. Your chance of having a C-section increases."