Medicinal Mushrooms and Breast Cancer: What is the latest research?

Coriolus versicolor (turkey tail)

Mushrooms have long been a delicacy in many culinary recipes, but what about their medicinal properties?  Have you walked by the typical white button mushroom in the grocery store and thought of it as a healing medicine? Not many have, but recent research is suggesting this mushroom and many others have cancer prevention properties.

A review article published December 2011 by Clinics Journal summarized the many individual mushroom studies that focused on breast cancer.  Most common mushrooms studied are Agaricus bisporus (white button), Coriolus versicolor (turkey tail), Ganoderma lucidum, Lentinus edodes (Shitake) and Grifola frondosa (Maitake).  The studies found therapeutic agents in the mushrooms such as lectin, arginine, and ergosterol.  These compounds were found to inhibit tumor growth, increase immune cell counts (particularly in patients undergoing chemotherapy and radiation treatment), and inhibit aromatase, an enzyme in breast cancer cells that will produce unwanted estrogen. 

One of the most researched mushrooms is turkey tail.  Japan extracted and approved a therapeutic compound called PSK (polysaccharide K) in 1980 and is now commonly used in Japan for adjuvant cancer therapy.  A study that was published in 2011 states that, “PSK can increase the effectiveness of monoclonal antibody therapy in breast cancer patients. Data from epidemiological and clinical studies on Coriolus versicolor [turkey tail] used as adjuvant therapy show that its use in breast cancer therapy is warranted and demonstrated its usefulness as a secondary preventative strategy.”  Although Japan’s breast cancer incidence rates have been on the rise since the mid-eighties, today their all-age mortality rate is 19.7 per 100,000 compared to the US at 22.8.  Their lower death rates may be attributed to using immune boosting and anti-tumor adjuvant therapies.

A US study recently published in May 2012 by Oncology journal found that up to 9 grams/day of turkey tail was beneficial for immune building and support in post primary cancer treatment.  The study suggested this therapy may be useful in preventing relapse. They concluded the study by stating that, “Research by our center continues to indicate that Coriolus versicolor represents a novel immune therapy with significant applications in cancer treatment.”

mushroomsThe promising research on mushrooms continues. In a 2006 study, the white button mushroom extract was used on breast cancer positive cells.  The extract greatly suppressed aromatase activity and estrogen production by the cells, thus reducing tumor growth.  When used in an animal study with mice, the oral intake of the mushroom extract significantly reduced tumor weight by 58% compared to control mice.  In addition, Ganaderma lucidum combined with green tea extract demonstrated suppression of a compound that activates breast cancer cells, thereby slowing growth and metastasis. Shitake was studied with breast cancer cells lines and authors observed anti-proliferative activity across all lines. Lastly, a study with 15 breast cancer patients taking extract from the maitake mushroom showed improved side effects during treatment.

Although these results seem conclusive to the benefits of these mushrooms, there is still wide scale human studies that need to be done before they will be widely used in the US. Fortunately, they have caught the attention of many with their seemingly positive effect on the immune system and tumor suppressing capabilities.  So next time you are at the grocery store and are admiring the abundance and variety of fungi available to you, feel free to indulge as you can feel great knowing you may be feeding your cells anti-cancer and immune building delicacies!

Alteri, Rick and Et Al. “Breast Cancer Facts & Figures 2013-2014.” Breast Cancer Facts & Figures 2013-2014. American Cancer Society, n.d. Web. 30 Sept. 2013.

Coriolus Versicolor.” Coriolus Versicolor. American Cancer Society, n.d. Web. 30 Sept. 2013.

Novaes, Maria, Fabiana Valadares, and Marilla Menezes. “The Effects of Dietary Supplementation with Agaricales Mushrooms and Other Medicinal Fungi on Breast Cancer: Evidence Based Medicine.” Clinics (Sao Paulo) 66.12 (2011): 2133-139. Print.

Thyr, Sara, ND. “Efficacy of Coriolus Versicolor (Yun Zhi) on Survival in Cancer Patients.” Natural Medicine Journal, 05 Dec. 2012. Web. 30 Sept. 2013.

Torkelson, Carolyn J., and Et Al. “Phase 1 Clinical Trial of Trametes Versicolor in Women with Breast Cancer.ISRN Oncology 251632. (2012) PubMed. Web. 30 Sept. 2013.

Written by Haylee Nye, NCNM Naturopathic Medicine Program.  Edited by Dr Elise Schroeder