Cranberries May Help with Ovarian Cancer Treatment

[August 2007] Improving the effect of chemotherapy against ovarian cancer may soon be as simple as drinking a glass of cranberry juice, suggests new research.

In laboratory experiments, pre-treating ovarian tumor cells with the juice gave a six-fold boost to the cancer-killing power of medications, researchers say.

The study results were presented this week at the national meeting of the American Chemical Society being held in Boston.

Ovarian cancer is the seventh most common cancer in the United States and the fifth leading cause of cancer death among American women, according to the US Centers for Disease Control (CDC). The American Cancer Society estimates that 22,430 new cases of ovarian cancer will be diagnosed in the US in 2007.

Initial Lab Studies Promising

Chemotherapy using platinum drugs, including cisplatin and paraplatin, is a mainstay treatment for ovarian cancer. However, cancer cells tend to develop resistance to platinum therapy and higher doses of the drugs can cause unwanted side-effects, including nerve damage and kidney failure.

Although preliminary, the cranberry boost related findings have the potential to save lives and reduce the harmful side effects associated with using high doses of platinum medications for the treatment of ovarian cancer. The researchers add that human studies are still needed. The new study adds to a growing number of potential health benefits linked to cranberries.

The study authors stress that the finding is still experimental and preliminary, but it could offer a new option for patients whose ovarian cancer has become resistant to treatment.

Focusing on Cranberries' Health Benefits

The new study focused on cranberry juice because of past research suggesting that the juice has a wide range of potential health benefits, including the ability to fight urinary tract infections, stomach ulcers, and cancer.

Ajay P. Singh, Ph.D., from Rutgers University, and his associates used ovarian cancer cells that were relatively resistant to platinum.

They treated the cells with various doses of a purified extract of commercially available cranberry drink (containing 27 percent pure juice), exposed the cells to the platinum drug paraplatin, and compared them to cells that were not exposed to the extract.

Paraplatin killed six times more cancer cells that were pre-treated with juice extract compared to cells that were exposed to the cancer drug alone, the researchers say.

The extract also slowed the growth and spread of some cancer cells. The maximum amount of juice extract given to the cells was the human equivalent of about a cup of cranberry juice, according to the researchers.

"Encouraging" Results

"This was surprising and encouraging," notes Dr. Singh, lead author on the study and a research associate and natural products chemist in the department of plant biology and plant pathology at Rutgers.

"We don't consider them to be a drug, but cranberries are already very well known to have antioxidants that boost the immune system and body strength, prevent urinary tract infection and help fight cardiovascular disease. So, we knew that cranberries would certainly not harm cancer patients. And now, we found that they actually increase sensitivity to chemo several-fold," he says.

The research team believes that the active compounds in the cranberry extract are powerful antioxidants called ‘A-type’ proanthocyanidins that are unique to cranberries and not found in other fruits.

The researchers add that they do not understand exactly how the cranberry compounds work. However, based on research by other groups, these compounds appear to bind to and block certain tumor promoter proteins found in the ovarian cancer cells. The result is that the cancer cells become more vulnerable to attack from the platinum drugs, the scientists say, noting that the cranberry compounds are not a cure for cancer.

Animal studies will begin soon and a new therapy could one day be available to consumers if further testing proves successful, Dr. Singh says.

For now, the researchers recommend that those with ovarian and other types of cancer seek their physician’s advice for the most effective treatment options.

Always consult your physician for more information.