Pilot study is first U.S. human trial of Japanese nutritional supplement
(SACRAMENTO, Calif.) - Investigators at UC Davis are studying a nutritional supplement derived from mushrooms to see if it can reduce tumor activity in men with prostate cancer.
The six-month pilot study is the first human trial outside of Japan using the substance known as activated hexose-containing compound, an active fraction found in shiitake mushrooms which has shown anti-cancer properties in some studies in Japan. Activated hexose-containing compound is also known as 1,3-beta glucan.
The compound is sold in Japan, Europe and the United States as a nutritional supplement.
The urology department at the UC Davis Medical Center is looking for men in the Sacramento area who have been treated for prostate cancer yet show rising levels of prostate specific antigen (PSA), a protein secreted by the prostate gland. In men who have been treated for prostate cancer, an elevated PSA almost always signifies recurrence.
Results of the study, UC Davis Cancer Center's first complementary medicine trial, will be used to help decide whether a double blind, placebo-controlled study is warranted.
"We decided to go ahead with the study because the company which manufactures the mushroom extract has intriguing data," says Ralph deVere White, director of the UC Davis Cancer Center and co-principal investigator of the study. "At the same time, we are treating it with the proper scientific oversight."
Prostate cancer patients were selected for the first study because of the ease of measuring the tumor marker - elevated PSA, which shows up in a simple blood test. The men who participate will have their PSA, weight, blood chemistry and other factors monitored monthly. Testing will be done on an outpatient basis at either the UC Davis Cancer Center, 4501 X Street, or the urology clinic at the Lawrence J. Ellison Ambulatory Care Center, 4860 Y Street in Sacramento.
The fungi extract is used in more than 400 hospitals in Japan and Asia as a complementary therapy for different cancers. According to data compiled by Amino Up Chemical Co. Ltd. in Sapporo, Japan - the company which makes activated hexose-containing compound - almost 10,000 cancer patients take the supplement every day.
"We don't see it as a replacement for medical care, but if it works, it could offer patients and their physicians more options," says Robert Hackman, executive director of the Center for Complementary and Alternative Medicine Research at UC Davis. Hackman is also co-principal investigator of the study.
An article published in the April 1998 issue of the journal Anti Cancer Drugs outlined animal studies at Hokkaido University School of Medicine which indicated that the compound may reduce tumor activity and lessen the side-effects of cancer treatment.
"The substance seems to act like a natural biological response modifier, because it may increase the activity of natural killer cells and cytokines, which boost the immune system," says deVere White, who is also chair of the urology department.
Men in the study will take six grams of the nutritional supplement per 50 kilograms of body weight. For the average man, this works out to be anywhere from 16 to 25 gel caps of activated hexose-containing compound daily with meals.
But don't try this at home - activated hexose-containing compound doesn't come from the shiitake mushrooms that you can buy in the grocery store, according to Hackman. Spores of shiitake and other mushrooms are cultivated in a high-tech factory in Sapporo until they sprout. The partially mature mushroom spores are treated in liquid broth with an enzyme which breaks down the cell wall and releases activated hexose-containing compound. This substance is in turn dried and harvested.
To be eligible for the study, men must have been diagnosed with adenocarcinoma of the prostate and have had either a radical prostatectomy or radiation therapy with rising PSA; metastatic prostate cancer with no hormone treatment therapy; or metastatic prostate cancer that has failed hormone therapy. It is also open to men with elevated PSAs who do not want to pursue conventional medical therapy.
The study will begin in mid-to-late January. Results should be known within the year. For information, call Stephanie Soares, research manager for the urology department, at (916) 734-7524.
For a copy of the article which appeared in the journal Anti Cancer Drugs or other research papers, call Laurie Slothower at (916) 734-9023.
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CONTACT: Laurie Slothower
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