Category Archives: Why It Works

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

Kobayashi Y, Kariya K, Saigenji K, Nakamura K.

Molecular Biology Laboratory, Kitasato University School of Medicine, Kanagawa, Japan.

Abstract

The protein-bound polysaccharide of Coriolus versicolor QUEL (PS_K) expresses superoxide dismutase (SOD) mimicking activity. Examination was made of the effects of PS-K on cancer cell lines following administration of the anti-cancer drug cisdiaminedichloroplatinum (cisplatin). Cell proliferation of each cell line was inhibited markedly by cisplatin from 0.5 to 5 micrograms/0.5 ml per well. Fifty percent of the inhibitory concentration (IC50) was 0.33 micrograms/0.5 ml per well in NRK-49F and human ovarian cancer cells, and 1.5 micrograms/0.5 ml per well in H4-II-E. PS-K 50 micrograms/0.5 ml per well prevented cytotoxicity due to cisplatin toward NRK-49F, but enhanced the cytotoxicity on H4-II-E and human ovarian cancer cells. Increase in lipid peroxide and decrease in SOD activity were observed following an IC50 dose of cisplatin. With PS-K 50 micrograms/0.5 ml per well, all the above were augmented in H4-II-E and ovarian cancer cells, but diminished in NRK-49F cell line. PS-K may have effect on cancer patients through its combining with cisplatin.

PMID: 7719382 [PubMed – indexed for MEDLINE]

Suppression of cancer cell growth in vitro by the protein-bound polysaccharide of Coriolus versicolor QUEL (PS-K) with SOD mimicking activity.

Kobayashi Y, Kariya K, Saigenji K, Nakamura K.

Molecular Biology Laboratory, Kotasato University School of Medicine, Kanagawa, Japan.

Abstract

The protein-bound polysaccharide of Coriolus versicolor QUEL (PS-K) expresses the mimicking activity of superoxide dismutase (SOD). Examination was made of the suppressive effects of PS-K on cancer cell lines cultured in vitro. The SOD activity of LLC-WRC-256 (Walker 256 fibrosarcoma) cell lines was less than that of NRK-49F (rat normal kidney fibroblast), H4-II-E (rat hepatoma) and H4-II-E-C3 (rat hepatoma) cell lines. This activity in Walker 256 fibrosarcoma cells increased by 3.6 times and H2O2 concentration, by 2.56 times by PS-K 500 micrograms/ml. Cell proliferation was consequently suppressed and living cells decreased to less than 50% of the cells cultured without PS-K. Catalase and glutathione peroxidase activity changed little by PS-K. The sensitivity of cancer cells to PS-K can be predetermined based on SOD activity in tumor tissue.

PMID: 7812358 [PubMed – indexed for MEDLINE]

http://www.ncbi.nlm.nih.gov/pubmed/7812358

Suppressive effects on cancer cell proliferation of the enhancement of superoxide dismutase (SOD) activity associated with the protein-bound polysaccharide of Coriolus versicolor QUEL.

Kobayashi Y, Kariya K, Saigenji K, Nakamura K.

Molecular Biology Laboratory, Kitasato University School of Medicine, Kanagawa, Japan.

Abstract

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.

PMID: 7812365 [PubMed – indexed for MEDLINE]

http://www.ncbi.nlm.nih.gov/pubmed/7812365

Enhancement of the antitumor effect by the concurrent use of a monoclonal antibody and the protein-bound polysaccharide PSK in mice bearing a human cancer cell line.

Kanoh T, Saito K, Matsunaga K, Oguchi Y, Taniguchi N, Endoh H, Yoshimura M, Fujii T, Yoshikumi C.

Kureha Chemical Ind. Co., Ltd., Biomedical Research Laboratories, Tokyo, Japan.

Abstract

The antitumor effects of a monoclonal antibody against a human cancer cell line and a protein-bound polysaccharide, PSK, obtained from cultured mycelia of Coriolus versicolor in basidiomycetes were examined. The IgG2a monoclonal antibody against the human colon cancer cell line colo 205 induced in vitro antibody-dependent macrophage-mediated cytotoxicity against the cancer cells, but only slightly suppressed the in vivo growth of the cancer cells. Concurrent use of PSK with the antibody enhanced the in vitro antibody-dependent macrophage-mediated cytotoxicity as well as the in vivo antitumor activity. These findings suggest that the combined use of a monoclonal antibody and PSK, which have different modes of action, may be useful in the treatment of cancer.

PMID: 7919129 [PubMed – indexed for MEDLINE]

http://www.ncbi.nlm.nih.gov/pubmed/7919129

In vitro bleaching of hardwood kraft pulp by extracellular enzymes excreted from white rot fungi in a cultivation system using a membrane filter.

Kondo R, Kurashiki K, Sakai K.

Department of Forest Products, Faculty of Agriculture, Kyushu University, Fukuoka 812, Japan.

Abstract

To clarify the role of excreted extracellular enzymes during long-term incubation in a pulp biobleaching system with white rot fungi, we developed a cultivation system in which a membrane filter is used; this membrane filter can prevent direct contact between hyphae and kraft pulp, but allows extracellular enzymes to attack the kraft pulp. Phanerochaete sordida YK-624 brightened the pulp 21.4 points to 54.0% brightness after a 5-day in vitro treatment; this value was significantly higher than the values obtained with Phanerochaete chrysosporium and Coriolus versicolor after a 7-day treatment. Our results indicate that cell-free, membrane-filtered components from the in vitro bleaching system are capable of delignifying unbleached kraft pulp. Obvious candidates for filterable reagents capable of delignifying and bleaching kraft pulp are peroxidase and phenoloxidase proteins. The level of secreted manganese peroxidase activity in the filterable components was substantial during strain YK-624 in vitro bleaching. A positive correlation between the level of manganese peroxidase and brightening of the pulp was observed.

PMID: 16349219 [PubMed]PMCID: PMC201411Free PMC Article

http://www.ncbi.nlm.nih.gov/pubmed/16349219

Immunomodulatory and antitumor activities of a polysaccharide-peptide complex from a mycelial culture of Tricholoma sp., a local edible mushroom.

Wang HX, Liu WK, Ng TB, Ooi VE, Chang ST.

Department of Biology, Chinese University of Hong Kong, Shatin.

Abstract

A polysaccharide-peptide complex (PSPC) with immunomodulatory and antitumor activities was obtained from a submerged mycelial culture of Tricholoma sp., a local edible mushroom. The polysaccharide-peptide complex exhibited a molecular weight of 17 K in gel filtration and a single band after SDS-polyacrylamide gel electrophoresis. It was characterized by non-adsorption on both DEAE-Sepharose CL-6B and CM-cellulose. It could activate the macrophages, stimulate the proliferation of T-cells, and inhibit the growth of sarcoma 180 in mice. It possessed more potent immunomodulatory and antitumor activities than Coriolus versicolor polysaccharopeptide (PSP) and deserves to be studied as a potential agent for immunomodulation and cancer therapy.

PMID: 7596231 [PubMed – indexed for MEDLINE]

http://www.ncbi.nlm.nih.gov/pubmed/7596231

Antitumor effects of a refined polysaccharide peptide fraction isolated from Coriolus versicolor: in vitro and in vivo studies.

Dong Y, Kwan CY, Chen ZN, Yang MM.

Department of Physiology, Faculty of Medicine, University of Hong Kong, Pokfulam, Hong Kong.

Abstract

RPSP, a refined polysaccharide peptide fraction isolated by fast performance liquid chromatography (FPLC) from the crude powder of total peptide-bound polysaccharides of cultivated Coriolus versicolor Cov-1 dose-dependently inhibited the proliferation of a human hepatoma cell line (HEPG2). The effective dose causing 50% inhibition following 3-day exposure to RPSP was 243 +/- 36 micrograms/ml for HEPG2. However, little or no inhibitory effects were detected in normal human foetal hepatocytes. On the other hand, in the pretreatment group, in which RPSP was administered i.p. for two weeks before sarcoma 180 inoculation in nude mice, the incidence of tumor growth was less (2 out of 5 mice) than that of the control group (all 5 mice). The tumor size of the control group was about 3-5 times bigger than that of the pretreatment group. In tumor-bearing nude mice, 5 days after sarcoma 180 inoculation, i.v. administration of RPSP significantly suppressed the growth of tumor mass. The inhibition rate was 93.6% on day 13. Furthermore, administration of RPSP did not cause any pathological lesions in vital organs of rabbits such as heart, liver, spleen, lung and kidney. In conclusion, these results indicate that RPSP acts by directly suppressing tumor cell growth in vitro and the prevention of in vivo growth of tumor mass is probably mediated also via its immunomodulating effects.

PMID: 8774067 [PubMed – indexed for MEDLINE]

http://www.ncbi.nlm.nih.gov/pubmed/8774067

Effects of Coriolus versicolor polysaccharides peptides on electric activity of mediobasal hypothalamus and on immune function in rats.

Yu GD, Yin QZ, Hu YM, Yin ZW, Gu ZL, Qian ZN, Qian ZM.

Laboratory of Neurobiology, Suzhou Medical College, China.

Abstract

AIM: The nervous mechanism of the immune potentiating effect of Coriolus versicolor polysaccharides peptides (PSP) was studied in Wistar rats.

METHODS: The unit discharge of the mediobasal hypothalamus (MBH) neurons was recorded extracellularly and the lymphocyte proliferation was measured.

RESULTS: PSP 1 g.kg-1 ig for 5 d increased the T-lymphocytes and promoted T-lymphocyte proliferation in spleen and peripheral blood. This promoting effect of PSP was blocked by MBH lesion. PSP increased the discharge frequency of MBH neurons, but no increase in discharge frequency was observed after treatment of PSP plus immune inhibitor, cyclosporin A.

CONCLUSION: MBH is involved in the immune-potentiating effect of PSP.

PMID: 9812756 [PubMed – indexed for MEDLINE]

http://www.ncbi.nlm.nih.gov/pubmed/9812756

Polysaccharide peptide (PSP) restores immunosuppression induced by cyclophosphamide in rats.

Qian ZM, Xu MF, Tang PL.

Department of Applied Biology and Chemical Technology, Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong.

Abstract

Polysaccharide peptide (PSP) is a protein-bound polysaccharide extracted from an edible mushroom, Coriolus versicolor. Effects of PSP (2g/kg/day) on cyclophosphamide (CPA, 40 mg/kg/2 days)-induced immunosuppression were investigated by determining lymphocyte proliferation, Natural killer (NK) cell formation, IgG and IL-2 concentration, WBC count and the weight of organs after rats were treated with or without CPA in the presence or absence of PSP. The results demonstrated that PSP possessed immunopotentiating effect, being effective in restoring CPA-induced immunosuppression such as depressed lymphocyte proliferation, Natural Killer cell function, production on white blood cell and the growth of spleen and thymus in rats as well as in increasing both IgG and IL-2 production on which CPA did not have significant effects under the conditions of our experiments. PSP can partly restore CPA-induced immunosuppression. Based on our findings and the data accumulated so far, it was suggested that PSP should be considered as an useful adjuvant especially combined with CPA or other chemotherapy in clinical treatment of cancer patients. The mechanism by which PSP restores the immunosuppression induced by CPA is unclear.

PMID: 9166995 [PubMed – indexed for MEDLINE]

Dose intensity of uracil and tegafur in postoperative chemotherapy for patients with poorly differentiated gastric cancer.

Sugimachi K, Maehara Y, Ogawa M, Kakegawa T, Tomita M.

Department of Surgery II, Faculty of Medicine, Kyushu University, Fukuoka, Japan.

Abstract

A retrospective analysis of postoperative chemotherapy had shown the continuous administration of UFT, an oral preparation of 1-(2-tetrahydrofuryl)-5-fluorouracil (tegafur) and uracil at a molar ratio of 1:4, to be effective for poorly differentiated gastric cancer. We therefore sought to determine prospectively the effective dose of postoperative chemotherapy with UFT for patients with poorly differentiated gastric cancer following a curative resection. We determined the effect of the combined intravenous administration of mitomycin C (MMC) and oral treatment with protein-bound polysaccharide Kreha (PSK), extracted from the basidiomycete Coriolus versicolor, and UFT at a dose of either 8 mg/kg or 12 mg/kg daily for 1 year. A total of 224 patients with poorly differentiated stage II-IV gastric cancer were entered into this study after undergoing a curative resection. No differences were observed between the two treatment groups in terms of prognostic factors, the toxicity rate or the doses of the drugs prescribed, other than UFT. The higher dose of UFT in maintenance therapy led to a decrease in the recurrence rate (P < 0.05), and increases in disease-free survival and cause-specific survival (P < 0.05). UFT at 12 mg/kg in postoperative chemotherapy was thus found- to improve the postoperative results with no increase in toxicity for poorly differentiated gastric cancer, and is also cost-effective for outpatients.

PMID: 9219507 [PubMed – indexed for MEDLINE]

http://www.ncbi.nlm.nih.gov/pubmed/9219507