One of many studies:
Comparsion of Anti-cancer Effect between two kinds of Polysaccharide Peptide of Coriolus versicolor on Human Tumor Cell Lines in Vitro.
Cloud mushroom contains several saccharides including polysaccharide peptide (PSP) and polysaccharide-K (PSK, krestin). The protein bound polysaccharides have been found to be immune-modulating and anti-tumor, and their polypeptide moieties are rich in aspartic acid and glutamic acid. By gas chromatography and HPLC, PSP has proved that in addition to glucose, it also contains five other monosaccharides – mannose, xylose, galactose, rhamnose and arabinose. The polysaccharide peptides can be found in the mycelium, while the fruiting body mainly contains polysaccharides
ScienceDaily (May 24, 2011) — A mushroom used in Asia for its medicinal benefits has been found to be 100 percent effective in suppressing prostate tumour development in mice during early trials, new Queensland University of Technology (QUT) research shows.
The compound, polysaccharopeptide (PSP), which is extracted from the ‘turkey tail’ mushroom, was found to target prostate cancer stem cells and suppress tumour formation in mice, according to an article written by senior research fellow Dr Patrick Ling in the online journal PLoS ONE, published by the Public Library of Science.
Dr Ling, from the Australian Prostate Cancer Research Centre-Queensland and Institute for Biomedical Health & Innovation (IHBI) at QUT, said the results could be an important step towards fighting a disease that kills 3,000 Australian men a year.
“The findings are quite significant,” Dr Ling said.
“What we wanted to demonstrate was whether that compound could stop the development of prostate tumours in the first place.
“In the past, other inhibitors tested in research trials have been shown to be up to 70 percent effective, but we’re seeing 100 percent of this tumour prevented from developing with PSP.
“Importantly, we did not see any side effects from the treatment.”
Dr Ling said conventional therapies were only effective in targeting certain cancer cells, not cancer stem cells, which initiated cancer and caused the disease to progress.
During the research trial, which was done in collaboration with The University of Hong Kong and Provital Pty Ltd, transgenic mice that developed prostate tumours were fed PSP for 20 weeks.
Dr Ling said no tumours were found in any of the mice fed PSP, whereas mice not given the treatment developed prostate tumours. He said the research suggested that PSP treatment could completely inhibit prostate tumour formation.
“Our findings support that PSP may be a potent preventative agent against prostate cancer, possibly through targeting of the prostate cancer stem cell population,” he said.
He said PSP had been previously shown to possess anti-cancer properties, and ‘turkey tail’ mushrooms (known as Coriolus versicolor or Yun-zhi) had been widely used in Asia for medicinal benefits.
However, Dr Ling said it was the first time it had been demonstrated that PSP had anti-cancer stem cell effects.
Although ‘turkey tail’ mushrooms had valuable health properties, Dr Ling said it would not be possible to get the same benefit his research showed from simply eating them.
A fundraiser has been organised in September to support further tests for the therapeutic potential of PSP against prostate tumours either alone or in combination with other anti-cancer compounds.
C.B.S. Laua, C.Y. Hoa, C.F. Kima, K.N. Leungb, K.P. Fungb, T.F. Tsec, H.H.L. Chanc, M.S.S. Chowa
Coriolus versicolor (CV), also known as Yunzhi, is one of the commonly used Chinese medicinal herbs. Although recent studies have demonstrated its antitumour activities on cancer cells in vitro and in vivo, the exact mechanism is not fully elucidated. Hence, the objective of this study was to examine the in vitro cytotoxic activities of a standardized aqueous ethanol extract prepared from Coriolus versicolor on a B-cell lymphoma (Raji) and two human promyelocytic leukemia (HL-60, NB-4) cell lines using a MTT cytotoxicity assay, and to test whether the mechanism involves induction of apoptosis. Cell death ELISA was employed to quantify the nucleosome production resulting from nuclear DNA fragmentation during apoptosis. The present results demonstrated that CV extract at 50 to 800 Ag/ml dose-dependently suppressed the proliferation of Raji, NB-4, and HL-60 cells by more than 90% (p < 0.01), with ascending order of IC50 values: HL-60 (147.3 F 15.2 Ag/ml), Raji (253.8 F 60.7 Ag/ml) and NB-4 (269.3 F 12.4 Ag/ml). The extract however did not exert any significant cytotoxic effect on normal liver cell line WRL (IC50 > 800 Ag/ml) when compared with a chemotherapeutic anticancer drug, mitomycin C (MMC), confirming the tumour-selective cytotoxicity. Nucleosome productions in HL-60, NB-4 and Raji cells were significantly increased by 3.6-, 3.6- and 5.6-fold respectively upon the treatment of CV extract, while no significant nucleosome production was detected in extract-treated WRL cells. The CV extract was found to selectively and dose-dependently inhibit the proliferation of lymphoma and leukemic cells possibly via an apoptosis-dependent pathway.
CHEONG-YIP HO, CHI-FAI KIM, KWOK-NAM LEUNG, KWOK-PUI FUNG, TAK-FU TSE, HELEN CHAN and CLARA BIK-SAN LAU
Coriolus versicolor (CV), also called Yunzhi, has been demonstrated to exert anti-tumor effects on various types of cancer cells. Our previous studies have demonstrated that a standardized aqueous ethanol extract prepared from CV inhibited the proliferation of human leukemia cells via induction of apoptosis. The present study aimed to evaluate the underlying mechanisms of apoptosis through modulation of Bax, Bcl-2 and cytochrome c protein expressions in a human pro-myelocytic leukemia (HL-60) cell line, as well as the potential of the CV extract as anti-leukemia agent using the athymic mouse xenograft model. Our results demonstrated that the CV extract dose-dependently suppressed the proliferation of HL-60 cells (IC50=150.6 ?g/ml), with increased nucleosome production from apoptotic cells. Expression of pro-apoptotic protein Bax was significantly up-regulated in HL-60 cells treated with the CV extract, especially after 16 and 24 h. Meanwhile, expression of anti-apoptotic protein Bcl-2 was concomitantly down-regulated, as reflected by the increased Bax/Bcl-2 ratio. The CV extract markedly, but transiently, promoted the release of cytochrome c from mitochondria to cytosol after 24-h incubation. In vivo studies in the athymic nude mouse xenograft model also confirmed the growth-inhibitory activity of the CV extract on human leukemia cells. In conclusion, the CV extract attenuated the human leukemia cell proliferation in vivo, and in vitro possibly by inducing apoptosis through the mitochondrial pathway. The CV extract is likely to be valuable for the treatment of some forms of human leukemia.
Full article: http://mushroomstudies.co/wp-content/uploads/2010/09/Coriolus-versicolor-Yunzhi-extract-attenuates-growth-of-human-leukemia-xenografts-and-induces-apoptosis-through-the-mitochondrial-pathway.pdf