Scientists identify chemopreventive agents in black raspberries

Researchers at the Ohio State Comprehensive Cancer Center found that anthocyanins, a class of flavonoids in black raspberries, inhibited growth and stimulated apoptosis in the esophagus of rats treated with an esophageal carcinogen.

"Our data provide strong evidence that anthocyanins are important for cancer prevention," said the study's lead author, Gary D. Stoner, Ph.D., a professor in the department of internal medicine at Ohio State University.

Stoner and his team of researchers fed rats an anthocyanin-rich extract of black raspberries and found that the extract was nearly as effective in preventing esophageal cancer in rats as whole black raspberries containing the same concentration of anthocyanins. This study demonstrates the importance of anthocyanins as preventive agents in black raspberries and validated similar in vitro findings. It is among the first to look at the correlation between anthocyanins and cancer prevention in vivo.

Stoner and his colleagues have conducted clinical trials using whole berry powder, which has yielded some promising results, but required patients to take up to 60 grams of powder a day. "Now that we know the anthocyanins in berries are almost as active as whole berries themselves, we hope to be able to prevent cancer in humans using a standardized mixture of anthocyanins," said Stoner.

"The goal is to potentially replace whole berry powder with its active components and then figure out better ways to deliver these components to tissues, to increase their uptake and effectiveness. Ultimately, we hope to test the anthocyanins for effectiveness in multiple organ sites in humans," said Stoner.

American Association for Cancer Research