Chemoprevention, Naturally: Findings On Plant-derived Cancer Medicines

ScienceDaily (Dec. 7, 2007) — The next cancer-fighting therapeutic could be growing in your garden. For example, a black raspberry-based gel might offer a means of stopping oral lesions from turning into a particularly dangerous and disfiguring form of cancer. And new studies show that cancer prevention might come in drinkable form: green tea extract, a powerful antioxidant, shows efficacy against colorectal cancer; and a new berry-rich beverage, made from a combination of known plant-based antioxidants, could prevent or slow the growth of prostate cancer.

That is, according to research presented December 6, at the American Association for Cancer Research's Sixth Annual International Conference on Frontiers in Cancer Prevention Research, being held in Philadelphia, Pennsylvania.

Topically applied black raspberry gel applied on oral premalignant tumors

Oral squamous cell carcinoma is a deadly cancer that, even when treated successfully, often leaves patients permanently disfigured. Other than radical surgery, there are few known treatments. Researchers at Ohio State University, however, report a Phase I/II trial demonstrating that a gel made from black raspberries shows promise in preventing or slowing the malignant transformation of precancerous oral lesions.

"Black raspberries are full of anthocyanins, potent antioxidants that give the berries their rich, dark color, and our findings show these compounds have a role in silencing cancerous cells," said Susan Mallery, D.D.S., Ph.D., professor in the Department of Oral Maxillofacial Surgery and Pathology at Ohio State University's College of Dentistry. "This gel appears to be a valid means of delivering anthocyanins and other cancer-preventing compounds directly to precancerous cells, since it slowed or reduced lesion progression in about two-thirds of study participants."

According to American Cancer Society statistics, oral cancer is one of the deadliest of all cancers, with about 35,000 new cases each year in the United States and 7,500 deaths annually. These cancers generally begin as small, often unnoticed, lesions inside the mouth. "More than a third of untreated precancerous oral lesions will undergo malignant transformation into squamous cell cancer, but we do not have the capability to predict which lesions will progress," Mallery said.

The National Cancer Institute-funded trial included 30 participants, 20 of whom had identifiable precancerous lesions, and 10 normal controls. Each of the participants was instructed to gently dry the lesion sites (or a pre-selected control site for the normal participants) and rub the gel into the area four times a day, once after each meal and at bedtime.

After six weeks, about 35 percent of the trial participants' lesions showed an improvement in their microscopic diagnosis, while another 45 percent showed that their lesions had stabilized. About 20 percent showed an increase in their lesional microscopic diagnoses. Importantly, none of the participants experienced any side effects from the gel.

"The trial was designed to test the safety of the gel and detect any possible toxicity, but the next obvious step is a multicenter, double-blind, placebo-controlled Phase II study," Mallery said. "Such a study would enable us to determine that the black raspberries are the active factor and not just the gel base or the act of drying and rubbing the lesions...."

http://www.sciencedaily.com/releases...1206124856.htm