A Quarterly Publication of City of Hope | Volume 18 Number 3 | Summer 2007
If new studies at City of Hope bear fruit, though, this simple fungus might command a little more attention.
City of Hope researchers are speeding findings about mushrooms’ cancer-fighting properties from the laboratory to clinical trials. After showing that extract from the white button mushroom slows breast cancer growth in mice, the City of Hope team is moving mushrooms into human studies involving breast and prostate cancers.
They hope to offer a way to reduce cancer risk — or even stunt cancer growth — through an addition to diet. The potential is so enticing that the California Breast Cancer Research Program, the American Institute for Cancer Research and the National Institutes of Health supported the lab studies, and the Mushroom Council recently donated $560,000 to support multidisciplinary pilot clinical trials.
photo: Paula MyersShiuan Chen explains lab results on mushrooms’ properties.
“Eating mushrooms would be an easy intervention,” said Shiuan Chen, Ph.D., director of the Division of Tumor Cell Biology and leader of the mushroom project. “It could provide a cost-effective, whole-food option for cancer risk reduction.”
Chen’s initial lab studies found that ingredients in mushrooms suppressed the effects of a natural substance in the body called aromatase. Blocking aromatase is a key way that physicians reduce circulating estrogen levels in breast cancer patients after menopause. That is important because about 75 percent of postmenopausal women with breast cancer have tumors that depend on estrogen to grow.
photo: Paula MyersPrzemyslaw Twardowski (left), Melanie Palomares and Shiuan Chen are investigating mushrooms’ potential to fight cancer.
“We’ve seen that aromatase inhibiting drugs are helpful in preventing recurrence in postmenopausal women with breast cancer,” said Melanie Palomares, M.D., M.S., assistant professor of medical oncology and population sciences. “And breast cancer survivors were found to develop fewer new breast cancers, too.”
Physicians currently recommend that postmenopausal women with hormone-responsive breast cancer take these drugs for two to five years. “At the end of this period, women can feel unsure about what to do next,” Chen said. “If mushrooms can reduce risk, perhaps we can tell them to eat mushrooms instead.”
That is the idea behind a phase I clinical trial led by Palomares. She and her colleagues are studying the effects when postmenopausal breast cancer survivors take tablets containing freeze-dried white button mushrooms for 12 weeks. Specifically, they will look at aromatase activity and levels of female hormones, as well as levels of conjugated linoleic acids, a group of compounds in the mushrooms that appear to deter cancer. They also will study effects on the immune system, cholesterol and bone health.
A second planned trial, meanwhile, investigates mushrooms’ potential in prostate cancer.
Laboratory research has shown that mushroom extract can lower levels of 5-alpha reductase, an enzyme linked to male hormones involved in prostate cancer.
Przemyslaw Twardowski, M.D., assistant professor of medical oncology, explains that opinions are mixed on how to treat a specific group of prostate cancer patients: men who were treated for cancer and appear to be cancer-free, but whose prostate-specific antigen levels, commonly called PSAs, have begun to rise. Cancer usually returns in these patients.
“There is much interest in a natural product that could intervene in this early stage,” Twardowski said, “and at least delay the need for other toxic therapies.”
I would like to know if Crimini mushrooms work as well as white button mushrooms.
I know that Shitaki is good as well. . .
I am at high risk for breast cancer, was on tomoxifin for 5 years. I eat salads making sure i put crimini mushrooms in it.