Trametes versicolor
Common & Other Names: (PSK, PSP, VPS, Turkey Tail, Yun Zhi, Kawaratake, Krestin, Coriolus versicolor, Polyporus versicolor, Polystictus versicolor)
Trametes versicolor is a mushroom of the Basidiomycetes class. It is used in traditional Chinese medicine as a tonic, and recent studies suggest that it has immunostimulant and anti-tumor properties. Polysaccharide-K (PSK), a proprietary product derived from Trametes, has been developed and approved for cancer treatment in Japan and is extensively used in Japan as an adjuvant to chemotherapy. When used this way, PSK appears to improve survival rates in patients with gastric and colorectal cancers. It may also benefit patients with esophageal cancer. Other Trametes extracts, such as polysaccharide-peptide (PSP) and VPS, are available as dietary supplements. One clinical study demonstrated that when used in conjunction with chemotherapy, PSP may benefit patients with advanced non-small cell lung cancer. Other clinical studies using Trametes extract alone or in combination with other botanicals also suggest positive immunomodulatory effects.
Trametes extracts are generally well tolerated but minor adverse effects have been reported.
Mechanisms of Action
Trametes versicolor is thought to be a biological response modifier. PSK has been found to induce cytokine expression in human peripheral blood mononuclear cells in vitro. In other studies, PSP, as well as a Coriolus extract, selectively induced apoptosis of human promyelocytic leukemia HL-60 cells. PSP also increased apoptotic cell death in cells that had been treated with camptothecin. In these cells, PSP reduced cellular proliferation, inhibited cell progression through both the S and G2 phases of DNA replication, reduced 3H - thymidine uptake, and prolonged DNA synthesis time. An additional in vitro study showed that a medicinal mushroom blend that included Trametes inhibited cell proliferation and induced cell cycle arrest at the G2/M phase in the invasive human breast cancer cell line MDA-MB-231. DNA-microarray analysis indicated that the mushroom extract inhibited the expression of cell cycle regulatory genes and suppressed metastatic behavior through the inhibition of cell adhesion, cell migration, and cell invasion. The inhibition of metastatic behavior was linked to the suppression of urokinase plasminogen activator (uPA). PSP has also been shown to inhibit the interaction between HIV-1 gp120 and CD4 receptor, HIV-1 transcriptase activity, and glycohydrolase enzyme activity associated with viral glycosylation.
Several animal studies report of synergism between PSK and biologic therapies, including a concanavalin A-bound L1210 vaccine and the IgG2a monoclonal antibody against human colon cancer cells. PSP induces cytokine production and T-cell proliferation, and prevents immune suppression due to cyclophosphamide in animal models. Peritoneal macrophages isolated from mice that were fed PSP show increased production of reactive nitrogen intermediates, superoxide anions, and tumor necrosis factor.
Non-small cell lung cancer patients have increased leukocyte and neutrophil counts, and increased serum IgG and IgM after consumption of PSP. Healthy volunteers as well as breast cancer patients who used a formula containing Trametes and Salvia were found to have elevated counts of T-helper lymphocytes (CD4+), a high ratio of CD4+/CD8+, and elevated absolute counts of B-lymphocytes. TNF-alpha and IL-8 gene expression were also found to be significantly induced after PSK administration in healthy volunteers and gastric cancer patients, although individual response varied. PSK was shown to induce apoptosis in promyelomonocytic leukemia HL-60 cells, and p38 MAPK (mitogen-activated protein kinas) was found to play an important role in this process.
Dosage
The typical dose of Trametes used in clinical trails during cancer treatment is 4 to 6 gm. For general immuno-support and cancer prevention, a formula containing several mushroom species (which may contain 25-50mg of Trametes) may be reasonable.
Safety
Trametes appears to be well tolerated, and the weight of the available evidence supports its safety with rare reported side affects. Up to 9 grams of Trametes daily for 6 months in women with Breast Cancer has failed to note any significant side effects and was deemed well tolerated.