The humble grape could tackle a painful side effect of breast cancer radiotherapy for which there is currently no effective treatment.

A clinical trial funded by Cancer Research UK and conducted by The Royal Marsden Hospital and The Institute of Cancer Research, will investigate the healing properties of grape seed on a potentially distressing side effect of high dose radiotherapy called radiation fibrosis.

Thousands of breast cancer patients worldwide are affected by the condition in the years after radiotherapy. The changes result in breast tissue becoming harder and sometimes tender. This can cause patients inconvenience, and in some women the changes are severe and have a major impact on day-to-day life.

The latest radiotherapy techniques are safer and more effective against cancer, but the possibility of permanent side effects cannot be eliminated.

Radiation fibrosis is a type of scarring that causes tissue to become hard and stiff. In addition, it is thought that a build up of fluid escaping from tiny blood vessels into the spaces between cells adds to hardness.

"Radiotherapy is followed over the years by tissue hardening and tenderness in the breast and underlying muscles in some women. We aim to test if grape seed extract reverses these changes and improves patients' quality of life," says Royal Marsden consultant Professor John Yarnold, the principal investigator for the trial.

"If successful, we aim to conduct further clinical trials in radiotherapy patients cured of other cancers where fibrosis may cause other serious medical problems."

Yarnold points out that it is not clear how fibrosis develops, but the most likely mechanism involves the continuous release of free radicals, triggered by radiotherapy.

These highly aggressive molecules are generated by many cell reactions in response to stress. They spread a kind of biological rust and can cause havoc in cells - damaging anything in their path, including DNA.

If free radicals are involved in breast tissue hardening, antioxidants could put a halt to this cellular blight by mopping up these molecules.

"Grape seeds contain a mixture of compounds called flavanoids, also found in other fruits and vegetables," says Yarnold. "They have antioxidant properties that may be superior to known antioxidants like vitamin E or C. There have already been promising small scale trials with antioxidants, but I believe grape seed extract has interesting potential."

He adds that the trial will also involve taking tissue biopsies so that researchers can understand the molecular mechanisms of any process observed.

SOURCE:
Cancer Research UK (http://www.cancerresearchuk.org)