Web Extra: Ratting on Prostate Cancer

Author: John Monczunski

Notre Dame’s Lobund-Wistar rats have a few suggestions for men who hope to lower their risk for prostate cancer: Eat a diet rich in soy-based foods and eat moderately. Those findings were confirmed in recent studies conducted by Morris Pollard, professor emeritus of biological sciences, using the unique germfree animals he first developed 28 years ago at the University.

While 30 percent of all Lobund-Wistar rats spontaneously develop prostate cancer by age 2, Pollard found that only 3 percent of those fed a diet rich in soy protein exhibited the disease at that age. The finding verifies other studies and epidemiological surveys that have shown fewer cases of prostate cancer among Japanese and Chinese men who maintain diets rich in soy foods. Soybeans have been found to contain estrogenlike compounds called isoflavones, which exhibit many anticancer mechanisms.

Earlier studies by Pollard revealed that Lobund-Wistar rats fed a restricted-calorie diet were less likely to develop prostate cancer than their “eat-drink-and-be-merry” brothers.

Pollard’s Lobund-Wistar rats have been hailed as one of the best available animal model systems for studying prostate cancer in man, particularly drug-treatment studies. The journal The Prostate called the animals “a powerful model to delineate mechanisms within the pathobiology of prostate cancer.”

The Lobund Lab director, who is overseer of the longest running medical research program at Notre Dame, has been using germfree animals to study disease mechanisms for more than 40 years. This spring the 85-year-old scientist, who has published more than 300 journal articles in his career, began a study to determine the effect of the anti-inflammatory drug Celebrex on prostate cancer.

Preliminary research by others suggests that the drug, which has been widely used for arthritis and recently was approved to prevent polyps that might lead to colon cancer, also may help reduce prostate cancer. While there is as yet no conclusive evidence, it is believed that nonsteroidal anti-inflammatory drugs such as Celebrex inhibit the growth of the arteries that feed tumors.

John Monczunski is an associate editor of this magazine.