Folate receptors may serve as a front door to ovarian cancer treatment

A new strategy that takes advantage of ovarian cancer’s reliance on folate appears to give relapse patients extra months of life with few side effects, researchers say.

The therapy uses the folate receptors on cancer cells as a sort of front door by pairing a substance attracted to the receptors with a chemotherapeutic agent too toxic to be given systemically, said Dr. Sharad Ghamande, Chief of the Section of Gynecologic Oncology at Georgia Health Sciences University.

Large numbers of folate receptors typically indicate the most aggressive ovarian cancers, as well as a variety of other cancers such as breast, lung and kidney.

The combination, called EC145, delivers a Vinca alkaloid directly inside cancer cells, improving effectiveness while reducing side effects particularly in women who overexpress folate receptors. A similar approach of pairing the folate ligand, which is attracted to the receptor, with a drug that makes those receptors glow, enables physicians to see how many folate receptors are present and who would be the best candidates for this treatment.

“We think this offers women with platinum-resistant disease a well-tolerated, effective treatment at a time when other drugs have failed them,” Ghamande said. “We hope it will give them more quality time to meet important milestones, such as seeing a grandson graduate from high school.” He noted that the strategy likely could enable targeted delivery of other drugs.

Folate may protect against ovarian cancer too A high dietary folate intake may play a role in reducing the risk of ovarian cancer, especially among women who consume alcohol, report Swedish researchers.

The findings add to a number of benefits attributed to the B vitamin, recommended especially for women of child-bearing age in order to reduce the risk of birth defects in newborns.

Writing in the Journal of the National Cancer Institute(vol.96, no.5, 396-402), the researchers from Stockholm's Karolinska Institute showed that women who consumed the highest amount of folate reduced their risk of ovarian cancer by 33 per cent compared to women who consumed the least amount of the vitamin.

But the benefits may be greater in women who consume more than two alcoholic beverages per week. These reduced their risk by 74 per cent compared to women consuming lesser amounts of alcohol if they also had high levels of folate.

Ovarian cancer affects more than 1,000 women a year in the UK, and is dangerous because it can often be at an advanced stage before symptoms appear and it is detected.

Ghamande is presenting findings of the phase 2 clinical trial at an Oct. 27-29 meeting in Brussels of the European Organisation for Research and Treatment of Cancer-National Cancer Institute-American Society of Clinical Oncology Annual Meeting on Molecular Markers in Cancer. The study enrolled 149 patients at 65 centers in North America and Poland; GHSU was among the top enrollers.