Turkey tail… what an interesting name for a mushroom, isn’t it?
Its fan shape, patterns and colours resemble the tail feather of a wild turkey, hence why its called turkey tail mushroom.
Turkey tail mushroom is also known as Coriolus versicolor/Trametes versicolor (scientific name), Yunzhi (or cloud mushroom) in Chinese and Kawaratake in Japanese. Turkey tail mushroom belongs to the Basidiomycetes class of fungi. It has been used in traditional Chinese medicine for over 2,000 years.
Turkey tail mushrooms contain several bioactive substances such as polysaccharides, proteins, peptides, amino acids, purpurins and terpenes.
The 2 commercial polysaccharide extracts used clinically in the Far East are:
- Polysaccharopeptide (PSP) derived from the COV-1 strain of turkey tail mushrooms in China
- Polysaccharide Krestin (PSK) derived from the CM-101 strain of turkey tail mushrooms in Japan
Both extracts are chemically and structurally similar.
The anti-cancer activities of PSP and PSK have been proven in cell culture, animal models and human clinical trials.
How Does Turkey Tail Mushroom Fight Cancer?
Both PSP and PSK exert immunomodulatory and anti-tumour effects.
The polysaccharides in PSP and PSK consist mainly of ß-glucans.
ß-glucans regulate immune functions by activating and/or increasing the number of various immune cells such as natural killer (NK) cells, monocyctes, macrophages, neutrophils, dendritic cells, T and B lymphocytes.
In cancer patients, the immune system is suppressed by tumour and/or chemotherapy. PSP and PSK can restore the immune response by activating immune cells to destroy cancer cells.
Direct Anti-Tumour Activity
PSP and PSP have direct cytotoxic effects on certain types of tumour cells via inhibition of proliferation, induction of apoptosis and sensitisation to various chemotherapy agents.
Advantages Of Turkey Tail Mushroom As An Immunotherapy Agent
- high tolerability, with no or minimal side effects
- improve survival and quality of life
- compatible with chemotherapy and radiation therapy
Clinical Studies of Turkey Tail Mushroom As A Cancer Adjunct Therapy
Turkey tail mushrooms are one of the most researched medicinal mushrooms.
Since 1970, trials in Japan have shown that PSK significantly extended survival at 5 years or beyond in cancers of the stomach, colon-rectum, oesophagus, nasopharynx and lung (non-small cell types), and in an HLA B40-positive breast cancer subset. In 1977, PSK was approved as a cancer therapy in Japan.
In China, PSP was developed in the 1980s and approved for clinical use in 1987. Besides cancer, it has been clinically tested to treat hepatitis, hyperlipidemia, chronic bronchitis, chemical-induced stress and other diseases.
In double-blind trials, PSP significantly extended 5-year survival in oesophagal cancer patients.
PSP significantly improved quality of life, provided substantial pain relief and boosted immune function in 70-97% of patients with cancers of the stomach, oesophagus, lung, ovary and cervix.
Turkey Tail Mushroom Alleviates Toxic Effects Of Conventional Cancer Treatment
1. PSP and PSK reduce chemotherapy side effects such as fatigue, loss of appetite, nausea, vomiting and pain.
2. PSP and PSK shorten or reduce the degree of immunosuppression due to chemotherapy or radiotherapy.
Bone marrow suppression is a serious side effect of chemotherapy. It increases the risk of neutropenia, a condition of abnormally low neutrophil (a type of white blood cell) count in the blood. Neutropenia increases a patient’s risk of infection and disrupting cancer treatment. PSP and PSK reduce bone marrow suppression, thereby increasing the tolerability and therapeutic efficacy of chemotherapy, improving quality of life and increasing overall survival.
Radiation therapy for cancer can cause lymphopenia (reduction in lymphocytes) and depressed natural killer (NK) cell function. In clinical trials, Coriolus versicolor alleviated lymphopenia in breast cancer and nasopharyngeal carcinoma (NPC) patients during and following radiotherapy. Oral administration of Coriolus versicolor elevated lymphocyte, T and B cell counts and increased NK cell anti-tumour activity.
Turkey tail mushroom extracts exert immune modulation effects on immune cells and direct cytotoxic effects on tumour cells.
They enhance the efficacy and reduce toxicity (adverse effects) of chemotherapy, and improve immunity. Consequently, cancer patients can tolerate further chemotherapy, experience improved quality of life and live longer.
Turkey tail and other medicinal mushrooms have been used in Eastern countries since ancient times. It is extensively researched in Japan and China, where it has been approved for clinical use for over 30 years.
Their health benefits are increasingly being recognised and studied in Western countries.