Earth's First Foods – Turkey Tail

Turkey Tail (Trametes versicolor)

mushrooms-turkeytail Other Names

Karwaratake (Japanese), Yun Zhi (Chinese).

Natural Habitat

Throughout North America, and worldwide in boreal, temperate, subtropical and tropical regions

Key Components

Polysaccharides (PSK and PSP), triterpenes, ergosterol (vitamin D precursor).

Overview

Turkey Tail is among the most widely researched medicinal mushrooms^¹. Used in the treatment of cancer in Asia for over 30 years, numerous in vitro, in vivo, and clinical studies have demonstrated marked anti-cancer effects^². Turkey Tail appears to exert direct apoptic and anti-proliferative actions on cancer cells, augments immune status, and to work synergistically with radio- and chemotherapy, as well as with several anti-cancer drugs^³. In numerous clinical trials, Turkey Tail extended survival times in a range of cancer types^⁴. Because of its very low toxicity, the mushroom has been of particular interest in cancer research. Turkey Tail extract has also been found active against HIV and herpes, and is a potent antibacterial against Candida albicans^{^5,6,7}. The mushroom demonstrates significant antioxidant activity and is liver protective^⁸. In traditional Chinese medicine, Turkey Tail is considered to clear dampness, increase energy, strengthen the physic, reduce phlegm, benefit chronic disease, and invigorate the spirit^⁹.

Two substances found in Turkey Tail have been widely studied for their evident anti-cancer properties: PSK and PSP. PSK is also known as Krestin and is an approved anti-cancer drug in Asia^¹⁰. Tested against tumors in animal studies, PSK restored immune response, augmented killer T cell activity, and blocked immunosuppressive substances^¹¹. PSK has also been shown to exert direct anti-cancer action against a number of tumors types, destroying cancerous cells and inhibiting tumor proliferation^¹².

PSK tested in combination with several anti-cancer drugs was found to augment their effects. Separate studies with the chemotherapy drugs cisplatin for ovarian cancer and docetaxel for pancreatic cancer showed supplementation with PSK increased the drugs’ effectiveness^{^13,14,15}.

In clinical trials with a number of cancers, Turkey Tail decreased reoccurrence rates and increased survival times^¹⁶. In stomach cancer, PSK in combination with surgery and chemotherapy doubled 2- and 5-year survival and extended 15-year survival, even in patients with advanced cases^¹⁷. In lung cancer patients, PSK increased 5-year survival by 2–4 times in all cancer stages^¹⁸. Similar remarkable increases in survival times were seen with PSK given in colorectal, esophageal, breast, and cervical/uterine cancer^¹⁹.

PSK appears to have a chemoprotective effect on healthy cells while sensitizing cancerous cells to chemo treatment^²⁰. Its ability to protect healthy cells from radio- and chemotherapy may be due to its high antioxidant activity^²¹. Turkey Tail can be used with debilitated patients, such as the elderly or those with AIDS, who might otherwise be unable to undergo chemotherapy treatment^²².

Several clinical studies have found Turkey Tail supplementation reduced chemotherapy side effects^²³. In double blind trials, it improved quality of life, provided substantial pain relief, and enhanced immune status among patients with a range of cancer types^²⁴.

PSP, another anti-cancer substance isolated from Turkey Tail, is a biological response modifier, meaning it activates the body’s response to infections. It is used as a supplementary cancer treatment in Asia^²⁵. PSP counteracts depressive effects on white blood cells and increases the production of immune defense cells^²⁶. Its also directly destroys tumors and prevents their proliferation. In human leukemia, pretreatment with PSP increased the response of cancerous cells to the anti-cancer agent Camptothecin^²⁷. Clinical studies with patients undergoing radio- or chemotherapy for esophageal, gastric, and lung cancer found PSP helped alleviate symptoms and improve immune status^²⁸. In lung cancer patients, PSP was associated with improved immune response and slower deterioration compared to a control group not given the extract^²⁹.

A powerful antioxidant, Turkey Tail increases the body’s levels of superoxide dismutase (SOD) and glutathione, two of the most important antioxidant defense enzymes^³⁰.

PSK’s anti-HIV properties combined with its immunostimulatory effects make it a potential candidate for the treatment of AIDS^³¹. PSK inhibits HIV from binding with lymphocytes³². It furthermore interferes with the reverse transcriptase process necessary for the disease’s replication, and blocks certain proteases key to the HIV life cycle^³³. A small clinical study reported remission of Kaposi’s Sarcoma, increased CD4 counts, and better energy in HIV patients while taking Turkey Tail supplement^³⁴.

PSK inactivates herpes virus in vitro, and may be useful in herpes treatment^³⁵.

PSK is protective against Candida bacterial infection. In animal studies, mice given a lethal infection of Candida albicans were protected by pre-treatment with Turkey Tail PSK^³⁶.

Turkey Tail has shown liver-protective properties, with PSK significantly inhibiting the growth of liver cancer in vitro, and helping to stimulate the recovery of healthy liver cells^³⁷. The antioxidant effects of PSP and its ability to promote glutathione may help prevent liver damage from toxins and carcinogens^³⁸.

^¹ Powell, M., 2010. Medicinal Mushrooms: A Clinical Guide, Mycology Press, East Sussex U.K. 76.

² Kidd, Parris M. The use of mushroom glucans and proteoglycans in cancer treatment. Alternative Medicine Review 5.1 (2000): 4-27.

^³ Fisher, Monte, and Li-Xi Yang. Anticancer effects and mechanisms of polysaccharide-K (PSK): implications of cancer immunotherapy. Anticancer research 22.3 (2001): 1737-1754.

^⁴ Powell, M., 2010. Medicinal Mushrooms: A Clinical Guide, Mycology Press, East Sussex U.K. 76-77

^⁵ Hirose, Kunitaka, et al. A biological response modifier, PSK, inhibits reverse transcriptase in vitro. Biochemical and biophysical research communications 149.2 (1987): 562-567.

^⁶ Monma, Yuko, Takashi Kawana, and Fumio Shimizu. In vitro inactivation of herpes simplex virus by a biological response modifier, PSK. Antiviral research 35.3 (1997): 131-138.

^⁷ Ohmura, Yoshio, et al. Protective effects of a protein-bound polysaccharide, PSK, on Candida albicans infection in mice via tumor necrosis factor-α induction. International immunopharmacology 1.9 (2001): 1797-1811.

^⁸ Ohmura, Yoshio, et al. Protective effects of a protein-bound polysaccharide, PSK, on Candida albicans infection in mice via tumor necrosis factor-α induction. International immunopharmacology 1.9 (2001): 1797-1811.

^⁹ Hobbs, Christopher. Medicinal mushrooms: an exploration of tradition, healing & culture. No. Ed. 2. Botanica Press, 1995. 165.

^¹⁰ Stamets, Paul, and C. Dusty Wu Yao. Mycomedicinals: An informational treatise on mushrooms. MycoMedia, 2002. 42.

^¹¹ Tsukagoshi, S., et al. Krestin (Psk).”Cancer Treatment Reviews 11.2 (1984): 131-155.

^¹² Maruyama, Shinjiro, et al. Protein-bound polysaccharide-K (PSK) directly enhanced IgM production in the human B cell line BALL-1. Biomedicine & Pharmacotherapy 63.6 (2009): 409-412.

^¹³ Kobayashi, Yuuki, et al. Enhancement of anti-cancer activity of cisdiaminedichloroplatinum by the protein-bound polysaccharide of Coriolus versicolor QUEL (PS-K) in vitro. Cancer Biotherapy & Radiopharmaceuticals 9.4 (1994): 351-358.

^¹⁴ Sohma, M., et al. Two cases of unresectable pancreatic cancer responding to combined chemotherapy with cisplatin, PSK and UFT]. Gan to kagaku ryoho. Cancer & Chemotherapy 14.6 Pt 1 (1987): 1926.

^¹⁵ PSK-mediated NF-kappaB inhibition augments docetaxel-induced apoptosis in human pancreatic cancer cells NOR-P1.

^¹⁶ Hobbs, Christopher. Medicinal Value of Turkey Tail fungus Trametes versicolor (L.: Fr.) Pilát (Aphyllophoromycetideae). A literature review. International Journal of Medicinal Mushrooms 6.3 (2004).

^¹⁷ Powell, M., 2010. Medicinal Mushrooms: A Clinical Guide, Mycology Press, East Sussex U.K.76-77.

^¹⁸ Powell, M., 2010. Medicinal Mushrooms: A Clinical Guide, Mycology Press, East Sussex U.K.76-77

^¹⁹ Kidd, Parris M. The use of mushroom glucans and proteoglycans in cancer treatment. Alternative Medicine Review 5.1 (2000): 4-27.

^²⁰ Stamets, Paul, and C. Dusty Wu Yao. Mycomedicinals: An informational treatise on mushrooms. MycoMedia, 2002. 43.

^²¹ Fisher, Monte, and Li-Xi Yang. Anticancer effects and mechanisms of polysaccharide-K (PSK): implications of cancer immunotherapy. Anticancer Research 22.3 (2001): 1737-1754.

^²² Fisher, Monte, and Li-Xi Yang. Anticancer effects and mechanisms of polysaccharide-K (PSK): implications of cancer immunotherapy. Anticancer Research 22.3 (2001): 1737-1754.

^²³ Kidd, Parris M. The use of mushroom glucans and proteoglycans in cancer treatment. Alternative Medicine Review 5.1 (2000): 4-27.

^²⁴ Kidd, Parris M. The use of mushroom glucans and proteoglycans in cancer treatment. Alternative Medicine Review 5.1 (2000): 4-27.

^²⁵ Wai-Hung, Sit, et al. Polysaccharopeptides derived from Coriolus versicolor potentiate the S-phase specific cytotoxicity of Camptothecin (CPT) on human leukemia HL-60 cells. Chinese Medicine 5.

^²⁶ Ng, T. B. A review of research on the protein-bound polysaccharide (polysaccharopeptide, PSP) from the mushroom Coriolus versicolor (Basidiomycetes: Polyporaceae). General Pharmacology 30.1 (1998): 1-4.

^²⁷ Wai-Hung, Sit, et al. Polysaccharopeptides derived from Coriolus versicolor potentiate the S-phase specific cytotoxicity of Camptothecin (CPT) on human leukemia HL-60 cells. Chinese Medicine 5.

^²⁸ Ng, T. B. A review of research on the protein-bound polysaccharide (polysaccharopeptide, PSP) from the mushroom Coriolus versicolor (Basidiomycetes: Polyporaceae). General Pharmacology 30.1 (1998): 1-4.

^²⁹ Tsang, K. W., et al. Coriolus versicolor polysaccharide peptide slows progression of advanced non-small cell lung cancer. Respiratory Medicine 97.6 (2003): 618-624.

^³⁰ Pang, Zhan-Jun, Yuan Chen, and Mei Zhou. Polysaccharide Krestin enhances manganese superoxide dismutase activity and mRNA expression in mouse peritoneal macrophages. The American Journal of Chinese Medicine 28.03n04 (2000): 331-341.

^³¹ Ng, Tzi Bun, Hexiang Wang, and D. C. C. Wan. Polysaccharopeptide from the Turkey Tail fungus Trametes versicolor (L.: Fr.) Pilát inhibits human immunodeficiency virus type 1 reverse transciptase and protease. International Journal of Medicinal Mushrooms 8.1 (2006): 39.

^³² Hirose, Kunitaka, et al. A biological response modifier, PSK, inhibits reverse transcriptase in vitro. Biochemical and Biophysical Research Communications 149.2 (1987): 562-567.

^³³ Hirose, Kunitaka, et al. A biological response modifier, PSK, inhibits reverse transcriptase in vitro. Biochemical and Biophysical Research Communications 149.2 (1987): 562-567.

^³⁴ Hirose, Kunitaka, et al. A biological response modifier, PSK, inhibits reverse transcriptase in vitro. Biochemical and Biophysical Research Communications 149.2 (1987): 562-567.

³⁵ Monma, Yuko, Takashi Kawana, and Fumio Shimizu. In vitro inactivation of herpes simplex virus by a biological response modifier, PSK. Antiviral Research 35.3 (1997): 131-138.

^³⁶ Ohmura, Yoshio, et al. Protective effects of a protein-bound polysaccharide, PSK, on Candida albicans infection in mice via tumor necrosis factor-α induction. International Immunopharmacology 1.9 (2001): 1797-1811.

^³⁷ Cai, Xinzhong, et al. Hepatoma cell growth inhibition by inducing apoptosis with polysaccharide isolated from Turkey Tail medicinal mushroom, Trametes versicolor (L.: Fr.) Lloyd (Aphyllophoromycetideae). International Journal of Medicinal Mushrooms 12.3 (2010): 257.

^³⁸ Ooi, Vincent Eng Choo. Pharmacological studies on certain mushrooms from China. International Journal of Medicinal Mushrooms 3.4 (2001).

Research

1. Anticancer effects and mechanisms of polysaccharide-K (PSK): implications of cancer immunotherapy

Fisher, M., and Yang, L.X. Anticancer Research. 2002. 22 (3), 1737-1754.

In this review article, the authors reviewed the anti-cancer effects of a polysaccharide (PSK) from Turkey Tail mushroom. Clinical trials show that PSK enhances the effects of drug treatments and boosts immune function in gastric, breast, colon, and lung cancers. Studies show that PSK stimulates immune system cytokines and natural killer cell activity. Research also shows that PSK not only inhibits the spread of cancer by influencing the enzymes associated with metastasis, but also inhibits the formation of cancer by blocking the effects of certain carcinogens. It also has antioxidant effects and ameliorates some of the side effects of chemotherapy.

2. The immunomodulator PSK induces in vitro cytotoxic activity in tumour cell lines via arrest of cell cycle and induction of apoptosis

Jimenez-Medina, E., et al. BMC Cancer. 2008. 8 (78).

In this in vitro study, researchers investigated the mechanism of action for an anti-cancer compound in Turkey Tail mushroom. The compound is a protein-bound polysaccharide and has shown anti-cancer properties in various experiments. Researchers looked at the compound’s effects on a number of tumor cell lines from different kinds of cancer. Testing revealed that the polysaccharide from Turkey Tail suppressed cancer cell proliferation by 22% to 84%. The polysaccharide induced cell cycle arrest at the G0/G1 phase, increased apoptosis (cell death), and increased caspase-3 activity (a protein associated with apoptosis).

3. Trametes versicolor mushroom immune therapy in breast cancer

Standish, L.J., et al. Journal of the Society of Integrative Oncology. 2008. 6 (3), 122-128.

In this review article, the authors discuss the large body of evidence supporting the use of Trametes versicolor (Turkey Tail mushroom) to boost immune activity against cancer. Of particular note are two proteoglycan compounds that have been shown to be effective against lung, gastric, colorectal, and breast cancers. They have been shown to ease chemotherapy side effects, boost immune activity, and improve survival rates. The authors believe that further clinical trials are warranted to test the efficacy of Turkey Tail compounds against breast cancer.

4. Medicinal value of Turkey Tail fungus Trametes versicolor (L.:Fr.) Pilát (Aphyllophoromycetideae). A literature review

Hobbs, C. International Journal of Medicinal Mushrooms. 2004. 6 (3).

In this review article, the author looked at the health benefits of Turkey Tail mushroom. PSK, or polysaccharide Krestin, is one of the most studied fractions of this mushroom. A large body of research shows that it boosts immune function, exhibits anti-viral effects, helps regulate cholesterol, improves quality of life for cancer patients, and prolongs cancer survival rates for certain types of cancer. No side effects from this mushroom fraction have been observed.

5. A biological response modifier, PSK, inhibits reverse transcriptase in vitro

Hirose, K., et al. Biochemical and Biophysical Research Communications. 1987. 149 (2), 562-567.

In this in vitro study, researchers tested the anti-viral effects of PSK, a polysaccharide compound from Turkey Tail mushroom. They tested PSK against HIV and made two key discoveries. First, PSK suppresses the ability of the HIV virus to bind with lymphocytes. Second, PSK suppresses reverse transcriptase, an enzyme that is necessary for a virus to replicate itself.

6. Polysaccharopeptide from the Turkey Tail fungus Trametes versicolor (L.:Fr.) Pilát inhibits human immunodeficiency virus type 1 reverse transcriptase and protease

Ng, T. B., et al. International Journal of Medicinal Mushrooms. 2006. 8 (1), 39-43.

In this series of experiments, researchers looked at the effects of a polysaccharopeptide from Turkey Tail mushroom on the HIV virus. They found that it blocks reverse transcriptase, an enzyme that is necessary for the virus to replicate itself. They also found that it inhibits protease, another enzyme needed for virus replication. Researchers conclude that this polysaccharopeptide has therapeutic value in treating AIDS patients.

7. In vitro inactivation of herpes simplex virus by a biological response modifier, PSK

Monma, Y., et al. Antiviral Research. 1997. 35 (3), 131-138.

In this series of in vitro experiments, researchers looked at the effects of PSK, a compound in Turkey Tail mushroom, on the Herpes simplex virus (HSV). They tested it against several strains of HSV. Results indicated that, in a dose dependent manner, PSK was effective against some strains of HSV but not others. Based on their data, the researchers conclude that PSK may be able to inactivate the virus in lesions in some cases of recurring herpes outbreaks.

8. Effects of a hot-water extract of Trametes versicolor (L.: Fr.) Lloyd (Aphyllophoromycetideae) on the recovery of rat liver function

Kim, B.K., et al. International Journal of Medicinal Mushrooms. 2000. 2 (1).

In a series of in vitro experiments, researchers looked at the effects of fractions of Turkey Tail mushroom on liver cells. They tested three different fractions for their ability to suppress the growth of liver cancer cells as well as their ability to improve function of normal liver cells. All three fractions effectively suppressed liver cancer cell growth. Two of the fractions also helped to promote healthy functioning of normal liver cells. Based on their data, researchers conclude that one fraction in particular, a hot water extract, is the best candidate for possible development as a therapeutic liver treatment.

9. Polysaccharopeptide from Coriolus versicolor has potential for use against human immunodeficiency virus type 1 infection

Collins, R.A., and Ng, T.B. Life Sciences. 1997. 60 (25), 383-387.

In this series of in vitro experiments, researchers evaluated a polysaccharopeptide from Turkey Tail mushroom for its effects on HIV type 1. It was effective against the virus in several ways. It blocked GP120 (a protein on the HIV virus that gains entry into cells) from harming the receptors on CD4 immune cells. It also blocked reverse transcriptase, an enzyme needed to replicate the virus. The Turkey Tail polysaccharopeptide is heat stable and does not harm healthy cells. Researchers believe it is a good candidate for an anti-viral agent against HIV.

10. Polysaccharopeptides derived from Coriolus versicolor potentiate the S-phase specific cytotoxicity of Camptothecin (CPT) on human leukemia HL-60 cells

Wan, J.M.F., et al. Chinese Medicine. 2010.

doi:10.1186/1749-8546-5-16

In this study, researchers looked at the ability of polysaccharopeptide from Turkey Tail mushroom to boost apoptosis in human leukemia cells treated with Camptothecin, a natural anti-cancer compound. Researchers observed decreased cell proliferation and increased effectiveness of the Camptothecin. The polysaccharopeptide induced cell death in the S-phase of the cell cycle (when DNA is replicated). This is significant because fast-growing tumors have a high percentage of cells in the S-phase. Nearby non-cancerous cells were not adversely affected by the treatment.

11. Enhancement of anti-cancer activity of cisdiaminedichloroplatinum by the protein-bound polysaccharide of Coriolus versicolor QUEL (PS-K) in vitro

Kobayashi, Y., et al. Cancer Biotherapy and Radiopharmaceuticals. 1994. 9 (4), 351-358.

Researchers looked at the effects of a polysaccharide from Turkey Tail mushroom used in combination with cisplatin (a chemotherapy drug) against cancer in vitro. Several cancer cell lines were treated with cisplatin and results measured; an increase in cancer cells was inhibited to varying degrees, depending on the cell line. When polysaccharide was added to normal rat kidney cells, it prevented cellular damage from the cisplatin. When added to rat liver cancer cells and human ovarian cancer cells, the polysaccharide enhanced the effects of cisplatin and increased cell death. Researchers conclude that it may be helpful to combine the polysaccharide with cisplatin treatment.

12. Coriolus versicolor (Yunzhi) extract attenuates growth of human leukemia xenografts and induces apoptosis through the mitochondrial pathway

Ho, C.Y., et al. Oncology Reports. 2006. 16 (3), 609-616.

In this study, researchers investigated the mechanism of action for apoptosis when cancer cells were treated with an extract from Turkey Tail mushroom. The extract inhibited multiplication of leukemia cells in vitro. It also stimulated the activity of the Bax protein, which induced apoptosis (cell death). The activity of the Bcl-2 protein, which blocks apoptosis, was suppressed. The extract also increased the activity of cytochrome c, another protein involved in apoptosis. In a related experiment, researchers used a xenograft model (in which human leukemia cells were implanted in mice). In this in vivo experiment the extract once again inhibited proliferation of the leukemia cells.

13. Cytotoxic activities of Coriolus versicolor (Yunzhi) extract on human leukemia and lymphoma cells by induction of apoptosis

Lau, C.B., et al. Life Sciences. 2004. 75 (7), 797-808.

In this in vitro study, researchers investigated the effects of an extract from Turkey Tail mushroom on several cancer cell lines (one lymphoma and two leukemia). The extract inhibited cancer cell proliferation by 90% in all the cell lines tested; the effects were dose dependent. They also compared the effects of the extract with a chemotherapy drug (mitomycin c) on healthy liver cells; the extract had no adverse effect on the healthy cells. Researchers conclude that the Turkey Tail extract can block proliferation of cancer cells; the mechanism of action involves apoptosis.

14. Coriolus versicolor polysaccharide peptide slows progression of advanced non-small cell lung cancer

Tsang, K.W., et al. Respiratory Medicine. 2003. 97 (6), 618-624.

In this double-blind, placebo-controlled trial, the effects of polysaccharide peptides from Turkey Tail mushroom were tested in patients with lung cancer. Patients were divided into two groups: a treatment group and a control group. The Turkey Tail compound was administered to those in the treatment group for 28 days and results were measured. Compared to the control group, those receiving treatment showed improved leukocyte and neutrophil counts (immune system cells) and had more body fat. There were no side effects from the treatment. More patients in the control group dropped out because their cancer worsened. Researchers conclude that the Turkey Tail compound can slow the progression of advanced non-small cell lung cancer.

15. Protective effects of a protein-bound polysaccharide, PSK, on Candida albicans infection in mice via tumor necrosis factor-alpha induction

Ohmura, Y., et al. International Immunopharmacology. 2001. 1 (9-10), 1797-1811.

In this in vivo study, researchers looked at the effects of a polysaccharide from Turkey Tail mushroom on life-threatening fungal infection in mice. They tested a variety of variables to find what worked best. Mice treated with the polysaccharide and then infected with Candida albicans 24 hours later had the greatest survival rates (60%). Mice who were also treated with cyclophosphamide (an anti-cancer drug) or carrageenan (a polysaccharide from seaweed) did not fare as well. Researchers found that the mushroom polysaccharide boosted immune activity; the mechanism of action was believed to be via tumor necrosis factor alpha activity.

16. Protective effects of a protein-bound polysaccharide, PSK, against Candida albicans infection in syngeneic tumor-bearing mice via Th1 cell functions

Ohmura, Y., et al. Cancer Biotherapy & Radiopharmaceuticals. 2003. 18 (5), 769-780.

In this in vivo study, researchers examined the effects of a polysaccharide from Turkey Tail mushroom on Candida albicans infection. Cancerous mice were divided into two groups: a group infected with Candida (the control group), and a group infected with Candida and given the mushroom polysaccharide. The mushroom group survived longer than the control group, and had less evidence of fungal infection. The mushroom group also showed other signs of enhanced immune function, including increased intracellular interferon gamma productivity and interleukin-12 activity. Researchers theorize that the Turkey Tail polysaccharide works via host immunity (Th1 cell function).

17. Antitumor effect of PSK and its combined effect with CDDP on ovarian serous adenocarcinoma-bearing nude mice

Ishii, K., et al. Nihon Sanka Fujinka Gakkai Zasshi. 1993. 45 (4), 333-339.

In this in vivo study involving mice, researchers looked at the effects of polysaccharide from Turkey Tail mushroom to enhance the effects of chemotherapy drug Cisplatin. Human ovarian cancer cells were implanted in mice and the mice were given the polysaccharide along with Cisplatin. Data indicated that the polysaccharide inhibited tumor growth and somewhat increased survival rates. It also stimulated natural killer cell activity. Mice who received Cisplatin plus the polysaccharide had lower blood levels of immunosuppressive acid protein; mice who received just the polysaccharide had higher levels. Researchers conclude that combining the polysaccharide from Turkey Tail mushroom with Cisplatin has a greater antitumor effect.

18. Protein-bound polysaccharide-K (PSK) directly enhanced IgM production in the human B cell line BALL-1

Maruyama, S., et al. Biomedicine & Pharmacotherapy. 2009. 63 (6), 409-412.

In this in vitro study, researchers examined the effects of polysaccharide from Turkey Tail mushroom on immune system B cells. They found that it boosted production of immunoglobulin M (antibodies which are produced by B cells) in a human B-cell line. Researchers conclude that the polysaccharide likely directly affects B cells and boosts both humoral (involving antibodies) and cellular immunity.

19. PSK-mediated NF-kappaB inhibition augments docetaxel-induced apoptosis in human pancreatic cancer cells NOR-P1

Zhang, H., et al. Oncogene. 2003. 22 (14), 2088-2096.

In this in vitro study, researchers looked at the ability of a polysaccharide from Turkey Tail mushroom to boost the effects of docetaxel (a chemotherapy drug). Human pancreatic cells were treated with docetaxel and the polysaccharide. Researchers found that this treatment suppressed the activity of nuclear factor kappa B (which, when dysregulated, is associated with cancer); in turn, the activity of a protein that blocks apoptosis (cell death) was also suppressed. The polysaccharide boosted the activity of caspase 3, a protein involved in apoptosis. Docetaxel has serious and damaging side effects; by combining small doses of docetaxel with the mushroom polysaccharide, researchers theorize that treatment of pancreatic cancer may be less harmful to patients while remaining effective.

20. Antimetastatic effects of PSK (Krestin), a protein-bound polysaccharide obtained from basidiomycetes: an overview

Kobayashi, H., et al. Cancer Epidemiology, Biomarkers & Prevention. 1995. 4 (3), 275-281.

In this review article, the authors discuss the effects of a polysaccharide from Turkey Tail mushroom on cancer metastasis. It has been show to inhibit some human lung cancer and prostate cancers. It has also been shown to prolong survival rates. In rodent models, the polysaccharide inhibits the spread of liver cancer, colon cancer, and leukemia. It works by suppressing tumor cell migration, tumor invasion and adhesion, suppression of angiogenesis (formation of new blood vessels), influencing various enzymes, and through antioxidant activity.