PSK has been the subject of investigation as an experimental adjunctive therapy for various types of cancers in Japan; however, sufficient data to demonstrate its efficacy for such purposes is lacking. Preliminary studies have examined PSK in conjunction with chemotherapy for colorectal cancer, non-small cell lung carcinoma,[unreliable medical source?] breast cancer,[unreliable medical source?] liver cancer, and leukemia.[original research?]
PSK is a protein polysaccharide consisting of a beta-glucan β-1,4 main chain with β-1,3 and β-1,6 side chains. The approximate molecular weight of PSK is 100,000 Da, and the protein component is reported at the β-1,6 side chain. PSK is isolated from the "CM-101" strain of Trametes versicolor. The analogous compound PSP, is derived from the "COV-1" strain of Trametes versicolor.
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- American Cancer Society's page for Trametes versicolor and Polysaccharide-K.
- Memorial Sloan-Kettering Cancer Center's page for Trametes versicolor and Polysaccharide-K.
- A "Detailed Scientific Review of Trametes versicolor and Polysaccharide-K" by the MD Anderson Cancer Center.
- Trametes versicolor and Polysaccharide-K information from Drugs.com.