The multiple and complex mechanisms of action of Coriolus Versicolor PSP have been demonstrated through in vitro and animal studies. Coriolus PSP has suppressed the growth of human cancer cell lines in mice (sarcoma 180, lung adenocarcinoma and Lewis lung cancer).
It has also inhibited incorporation of two structural units of DNA (uridine and thymidine) in Ehrlich ascites tumor cells, inhibited the growth of P388 leukemia cells, and demonstrated anti-proliferative activity against cell lines of human gastric cancer, lung cancer, lymphoma, and mononuclear leukemia.
Coriolus PSP has reversed tumor-induced immunodeficiencies in sarcoma-bearing mice by increasing immunoglobulin G and C3 complement levels9. It has also been associated with increases in white blood cell count, serum IgG, CD4, CD8, B-lymphocytes, and neutrophils, along with a higher survival rate of tumor bearing mice3. Many of these effects have been attributed to PSP being a strong scavenger of superoxide and hydroxyl radicals. Coriolus Versicolor PSP has also been found to restrict the cell cycle of HL-60 leukemic cells through apoptosis.
These and other immune effects of PSK and PSP are described in reviews by Fisher and Yang, Ooi and Liu and Chu, Ho and Chow.