Black Raspberries Reduce Colon Cancer Risk

CHICAGOBlack raspberries may be highly effective in preventing colorectal tumors in two mouse models of the disease, according to a new study published in the November issue of Cancer Prevention Research.

Building on previous research that found black raspberries have antioxidant, anti-cancer, anti-neurodegenerative and anti-inflammatory properties, researchers at the University of Illinois at Chicago investigated the fruit's ability to prevent colon cancer.

Researchers used two strains of mice, Apc1638 and Muc2, which each have a specific gene knocked out, causing the mice to develop either intestinal tumors (in the case of Apc1638) or colitis in the case of Muc2. Colitis is an inflammation of the large intestine that can contribute to the development of colorectal cancer. Both mouse strains were randomized to be fed either a Western-style, high-risk diet or the same diet supplemented with 10 percent freeze-dried black raspberry powder for 12 weeks.

The researchers found that in both mouse strains the black raspberry-supplemented diet produced a broad range of protective effects in the intestine, colon and rectum and inhibited tumor formation.

In the Apc1638 mice, tumor incidence was reduced by 45 percent and the number of tumors by 60 percent. The researchers found that black raspberries inhibited tumor development by suppressing a protein, known as beta-catenin, which binds to the APC gene.

In the Muc2 mice, tumor incidence and the number of tumors were both reduced by 50 percent, and black raspberries inhibited tumor development by reducing chronic inflammation associated with colitis.