Wayne State study finds soybean compounds enhances effects of cancer radiotherapy

Detroit - A Wayne State University researcher has shown that compounds found in soybeans can make radiation treatment of lung cancer tumors more effective while helping to preserve normal tissue.

A team led by Gilda Hillman, Ph.D., professor of radiation oncology at Wayne State University's School of Medicine and the Barbara Ann Karmanos Cancer Institute, had shown previously that soy isoflavones, a natural, nontoxic component of soybeans, increase the ability of radiation to kill cancer cells in prostate tumors by blocking DNA repair mechanisms and molecular survival pathways, which are turned on by the cancer cells to survive the damage radiation causes.

At the same time, isoflavones act to reduce damage caused by radiation to surrounding cells of normal, noncancerous tissue. This was shown in a clinical trial conducted at WSU and Karmanos for prostate cancer patients treated with radiotherapy and soy tablets.

In results published in the journal Nutrition and Cancer in 2010, those patients experienced reduced radiation toxicity to surrounding organs; fewer problems with incontinence and diarrhea; and better sexual organ function. Hillman's preclinical studies in the prostate tumor model led to the design of that clinical trial.

Soy isoflavones can make cancer cells more vulnerable to ionizing radiation by inhibiting survival pathways that are activated by radiation in cancer cells but not in normal cells. In normal tissues, soy isoflavones also can act as antioxidants, protecting those tissues from radiation-induced toxicity.

source: EurekAlert