Two genes linked to deadly ovarian cancer
Genes linked to a riskier type of ovarian cancer
U.S. researchers have identified genetic mutations in two genes that are associated with a hardest-to-treat ovarian cancer, according to two studies published in the New England Journal of Medicine. The finding may help doctors understand how ovarian cancer develops and how they can be better treated.
The genes are associated with ovarian clear cell carcinoma, one most aggressive form of ovarian cancer, which does not respond to chemotherapy and accounts for about 12 percent of all cases of ovarian cancer.
Dr. Bert Vogelstein, Nickolas Papadopoulos and colleagues at Johns Hopkins University in Baltimore named one gene as ARID1A and the other as PPP2R1A. Genetic testing tools may be developed to identify the genetic mutations.
But it remains unknown how likely it could be for a woman with the mutations to develop ovarian cancer.
Another study led by Dr. David Huntsman of the British Columbia Cancer Agency focused on ARID1A found that the gene mutation is present not only in ovarian clear cell carcinoma, but also in an ovarian tumor linked to endometriosis, which is implicated in some cases in development of the hardest-to-treat ovarian cancer.
ARID1A is found to be a tumor suppressor gene and a mutation can permanently turn on the gene leading to a improper biological function. This mutation is found also in some cases of lung and breast cancer.
What is ovarian cancer?
Ovarian cancer is a malignant tumor that grows in tissues of the ovary - a female reproductive gland in which eggs are produced. The disease is hard to be diagnosed early and it is the fifth leading cause of cancer death among women.
The disease is expected to be diagnosed in 21,800 women and to kill 13,850 in 2010, according to the U.S. National Cancer Institute.
The risk factors for ovarian cancer include being older, having a family history of ovarian cancer, taking hormone replacement therapy after menopause, using fertility drugs, being obese, having increased blood levels of cancer antigen 125, and having some genetic conditions, according to American Institute for Cancer Research.
Some factors that may decrease the risk of ovarian cancer include giving birth, breastfeeding, having had a tubal ligation or hysterectomy.
A healthy diet is believed to help prevent or treat ovarian cancer
One new study in the March 2010 issue of the Journal of American Dietetic Association suggests that eating lots of fruit and vegetables prior to diagnosis may better ovarian cancer survival.
Dolecek T.A. and colleagues from the University of Illinois at Chicago analyzed data from 341 women diagnosed with epithelial ovarian cancer and found those who consumed highest amounts of fruit and vegetables were 39 percent less likely to die in a period of 7 to 11 years. Survival is defined as having lived more than five years of diagnosis.
Those who had highest intake of vegetables prior to diagnosis were 34 percent less likely to die from the cancer, the study found.
In contrast, those who had highest amounts of meats were 128 percent more likely to die from ovarian cancer compared to those who ate lowest amounts of meats, particularly the red and cured or processed meats.
Additionally, those who ate highest amounts of all types of milk products were at 115 percent increased risk of dying from ovarian cancer compared to those who ate the lowest amounts.
Dy David Liu