Researchers at Brigham and Women’s Hospital have found initial laboratory and epidemiological evidence that, for the first time, demonstrates that ginkgo may help lower a woman’s risk of developing ovarian cancer. The findings were presented at the American Association for Cancer Research’s annual meeting in Baltimore on Oct. 31, 2005.
In a population-based study, which involved more than 668 ovarian cancer cases and 720 healthy, matched controls, women who took ginkgo supplements for six months or longer were shown to have a 60 percent lower risk of ovarian cancer.
Daniel Cramer, MD, ScD, director of the Obstetrics and Gynecology Epidemiology Center at BWH, and colleague Bin Ye, PhD, found that ginkgo, echinacea, St. John’s wort, ginseng, and chondroitin were the most commonly used herbals among study participants. A further analysis of the data showed that ginkgo was the only herb linked to ovarian cancer prevention. The preventive effect was more pronounced in women with non- muncious ovarian cancers, with data showing that ginkgo may reduce the risk of this type of ovarian cancer by 65-70 percent.
The team then took the evidence demonstrated in the population study to the laboratory. In these experiments the researchers tested whether or not gingko, when introduced to ovarian cancer cells, may interfere with cell growth.
In vitro experiments showed that a low dosage of gingkolide caused ovarian cancer cells to stop growing. The researchers observed an 80 percent growth reduction in non-mucinious ovarian cancer cells. Gingkolides appeared to be less effective against the mucinous type of ovarian cancer cells, which paralleled the findings observed in the epidemiological study.
“Among the mixture of ginkgo chemicals,” said Ye, “we found laboratory evidence that ginkgolide A and B, terpene compounds, are the most active components contributing to this protective effect.”