Folk Remedy, Food Spice May Fight Cancer

FRIDAY, June 10, 2005 (HealthDay News) -- Cancer researchers have been given a million-dollar grant to investigate the therapeutic value of the folk medicine propolis and the food spice turmeric.

The U.S. National Cancer Institute grant is earmarked for the study of the two alternative remedies, each of which has shown promise in reducing risks for breast, prostate and colorectal malignancies, and in enhancing cancer treatment.

Propolis and turmeric are rich in plant polyphenolic compounds that exhibit potent antitumor activities, the researchers said.

"A very interesting property of these compounds is that they have been shown to cause cell death in tumor cells but not in normal cells," study lead investigator Costas Koumenis, assistant professor of radiation oncology at Wake Forest University Baptist Medical Center, in Winston-Salem, N.C., said in a prepared statement.

Propolis is a resinous substance collected by bees from the bark and leaves of trees and plants. Since ancient times, propolis extracts have been used as antibacterial and anti-inflammatory treatments. The major active ingredient in propolis is caffeic acid phenethyl ester (CAPE). Recent research has found CAPE protecting mice against radiation-induced inflammation and skin damage, and also protecting rats against certain forms of heart muscle damage after they were given chemotherapy drugs.

Turmeric, a spice found in curries, contains the compound curcumin. Previous studies found an association between diets rich in curcumin and greatly reduced rates of colon cancer, the researchers said.

"Based on these interesting properties of CAPE and curcumin and their good safety profile, our lab has carried out studies in cell cultures and experimental animal tumor, showing that the compounds can make tumor cells more susceptible to chemotherapy and radiation, while having little effect or even reducing some of the toxic effects of radiation on normal cells," Koumenis said.

For the next four years, he and his team will study if CAPE and curcumin enhance radiation therapy in deadly brain tumors called gliomas and other tumors in animals. They'll also attempt to learn how the two compounds make tumor cells more sensitive to radiation, while protecting normal cells.

"The differential effects of this class of compounds on normal and tumor cells are well-documented, but still remains a mystery," Koumenis said. "Discovering how they are able to do this may open the way to design drugs with similar properties but are even more potent."

More information

The U.S. National Cancer Institute has more about cancer prevention.