Suppressive effects on cancer cell proliferation of the enhancement of superoxide dismutase (SOD) activity associated with the protein-bound polysaccharide of Coriolus versicolor QUEL.
The protein-bound polysaccharide of Coriolus versicolor QUEL (PS-K) expresses superoxide dismutase (SOD) mimicking activity. Examination was made of the suppressive effects of PS-K on cancer cell lines cultured in vitro. SOD activity of incorporated PS-K was 5.88 u/mg in LLC-WRC-256 (Walker 256 fibrosarcoma) cells and 4.73 u/mg in NRK-49F (rat normal kidney fibroblast) cells. SOD activity in both cell types was enhanced about 7-8 times that of the original PS-K. PS-K was not incorporated into H4-11-E or H4-11-E-C3 (rat hepatoma) cells. SOD activity of 1 mg/ml PS-K incubated with cell homogenates of LLC-WRC-256 cells for 6 hours increased from 0.68 u/mg to 1.35 u/mg. SOD activity of PS-K 1 mg/ml in 0.05 M phosphate buffer incubated with 50 microM NADPH increased from 0.68 u/mg. The consumption of NADPH at the same concentration was confirmed spectrophotometically by incubation with PS-K. The mechanism for the enhancement of SOD activity associated with PS-K is considered to be collaboration with NADPH as an electron donor in the cytoplasm of cancer cells whose SOD and coupling enzyme activities are significantly lower than in normal cells.
Kobayashi
Y
Y
Molecular Biology Laboratory, Kitasato University School of Medicine, Kanagawa, Japan.
Kariya
K
K
Saigenji
K
K
Nakamura
K
K
D000818:Animals; D002279:Carcinoma 256, Walker / Q000473:pathology*; D002455:Cell Division / Q000187:drug effects; D003864:Depression, Chemical; D004789:Enzyme Activation / Q000187:drug effects; D005347:Fibroblasts / Q000187:drug effects; D007155:Immunologic Factors / Q000494:pharmacology*; D008114:Liver Neoplasms, Experimental / Q000378:metabolism / Q000473:pathology*; D009249:NADP / Q000494:pharmacology; D009363:Neoplasm Proteins / Q000378:metabolism; D011509:Proteoglycans / Q000494:pharmacology*; D051381:Rats; D013482:Superoxide Dismutase / Q000378:metabolism*; D014407:Tumor Cells, Cultured / Q000187:drug effects
D007155:Immunologic Factors; D009363:Neoplasm Proteins; D011509:Proteoglycans; C010770:polysaccharide-K; D009249:NADP; D013482:Superoxide Dismutase