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Leukemia

Induction of cell cycle changes and modulation of apoptogenic/anti-apoptotic and extracellular signaling regulatory protein expression by water extracts of I’m-Yunity™ (PSP)

Aqueous extracts of I’m-Yunity™ (PSP) induces cell cycle arrest and alterations in the
expression of apoptogenic/anti-apoptotic and extracellular signaling regulatory proteins in human leukemia
cells, the net result being suppression of proliferation and increase in apoptosis. These findings may
contribute to the reported clinical and overall health effects of I’m-Yunity™ (PSP). […]

Enhanced induction of immune resistance by concanavalin A-bound L1210 vaccine and an immunopotentiator prepared from Coriolus versicolor.

Combined administration of a vaccine consisting of a small number (2 X 10(6)) of L1210 murine leukemic cells treated with glutaraldehyde and concanavalin A and a protein-bound polysaccharide preparation of Coriolus versicolor induced synergistic resistance to L1210 leukemia in BALB/c X DBA/2CrF1 mice. This effect was dependent on the dose and timing of the administration of the protein-bound polysaccharide preparation, being most effective at the time of or 1 day after the second vaccination. Induced resistance was not cross-reactive with P388 murine leukemia, indicating specificity of resistance. This immunopotentiation by the protein-bound polysaccharide did not occur when L1210 cells treated with glutaraldehyde, but not with concanavalin A, were used as a vaccine.[…]

Anticancer effects and mechanisms of polysaccharide-K (PSK): implications of cancer immunotherapy.

Polysaccharide-K (polysaccharide-Kureha; PSK), also known as krestin, is a unique protein-bound polysaccharide, which has been used as a chemoimmunotherapy agent in the treatment of cancer in Asia for over 30 years. PSK and Polysaccharopeptide (PSP) are both protein-bound polysaccharides which are derived from the CM-101 and COV-1 strains of the fungus Coriolus versicolor by Japanese and Chinese researchers, respectively. Both polysaccharide preparations have documented anticancer activity in vitro, in vivo and in human clinical trials, though PSK has been researched longer and has therefore undergone more thorough laboratory, animal and clinical testing. Several randomized clinical trials have demonstrated that PSK has great potential as an adjuvant cancer therapy agent, with positive results seen in the adjuvant treatment of gastric, esophageal, colorectal, breast and lung cancers. These studies have suggested the efficacy of PSK as an immunotherapy or biological response modifier (BRM). BRMs potentially have the ability to improve the “host versus tumor response,” thereby increasing the ability of the host to defend itself from tumor progression. The mechanisms of biological response modification by PSK have yet to be clearly and completely elucidated. Some studies suggest that PSK may act to increase leukocyte activation and response through up-regulation of key cytokines. Indeed, natural killer (NK) and lymphocyte-activated killer (LAK) cell activation has been demonstrated in vivo and in vitro, and recent genetic studies reveal increased expression of key immune cytokines in response to treatment with PSK. An antimetastatic action of PSK has also been demonstrated and is perhaps attributed to its potential to inhibit metalloproteinases and other enzymes involved in metastatic activity. PSK has also been shown to cause differentiation of leukemic cells in vitro, and this effect has been attributed to induction of differentiation cytokines. PSK has further been shown to have antioxidant capacity which may allow it to play a role as a normal tissue chemo- and radio-protector when used in combination with adjuvant or definitive chemotherapy and/or radiotherapy in the treatment of cancer, while it may also enable it to defend the host from oxidative stress. Interestingly, studies have also shown that PSK may actually inhibit carcinogenesis by inhibiting the action of various carcinogens on vulnerable cell lines. This action of PSK may play a role in preventing second primary tumors when an inducing agent, such as tobacco or asbestos, is suspected and may also prevent second malignancies due to the carcinogenic effects of radiotherapy and cytotoxic chemotherapy. Another very important aspect of chemoimmunotherapy, in general is that it may be used on debilitated patients such as those with AIDS and the elderly who might otherwise be denied potentially helpful adjuvant cytotoxic chemotherapy. Further determination of the mechanisms of these anti-cancer, immunostimulating and biological response modifying effects of PSK as well as of other protein-bound polysaccharides is certainly warranted. Indeed, with modern cellular and molecular biology techniques, a better understanding of the specific molecular effects of PSK on tumor cells as well as leukocytes may be determined. Much of the research that has been done on PSK is outlined in this paper and may serve as a foundation toward determining the mechanisms of action of this and other protein-bound polysaccharides in the treatment of cancer. This information may open new doors in the development of novel strategies for the treatment of malignancies using adjuvant immunotherapy in combination with surgery, chemotherapy and/or radiotherapy.[…]

The cell death process of the anticancer agent polysaccharide-peptide (PSP) in human promyelocytic leukemic HL-60 cells.

The polysaccharide peptide (PSP) isolated from the mycelia of Chinese Medicinal fungus Coriolus versicolor has proven benefits in clinical trials in China but the mechanism of action has not been elucidated. In this study, HL-60 cell line was used to investigate the anti-proliferation and cell death process of PSP. The cytotoxicity of PSP on normal human T-lymphocytes was also evaluated. We show that PSP induced apoptosis of human promyelocytic leukemia HL-60 cells but not of normal human T-lymphocytes. The apoptotic machinery induced by PSP was associated with a decrease in Bcl-2/Bax ratio, drop in mitochondrial transmembrane potential, cytochrome c release, and activation of caspase-3, -8 and -9. Activation of the cellular apoptotic program is a current strategy for the treatment of human cancer, and the selectivity of PSP to induce apoptosis in cancerous and not on normal cells supports its development as a novel anticancer agent.[…]

Differential effect of Coriolus versicolor (Yunzhi) extract on cytokine production by murine lymphocytes in vitro

Being one of the commonly used Chinese medicinal herbs, Coriolus versicolor (CV), also named as Yunzhi, was known to possess both anti-tumor and immunopotentiating activities. The present study aimed to investigate the in vitro immunomodulatory effect of a standardized ethanol–water extract prepared from CV on the proliferation of murine splenic lymphocytes using the MTT assay, and the production of six T helper (Th)-related cytokines using the enzyme-linked immunosorbent assay (ELISA) technique. The results showed that the CV extract significantly augmented the proliferation of murine splenic lymphocytes in a time- and dose-dependent manner, maximally by 2.4-fold. Moreover […]

Cytotoxic activities of Coriolus versicolor (Yunzhi) extract on human leukemia and lymphoma cells by induction of apoptosis

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. […]

Coriolus versicolor (Yunzhi) extract attenuates growth of human leukemia xenografts and induces apoptosis through the mitochondrial pathway

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 […]

Chemoimmunotherapy with Krestin in acute leukemia

The purpose of this study was to determine if immunotherapy with Krestin can prolong the durations of complete remission and survival. The patients were placed at random in the chemotherapy and chemoimmunotherapy groups. The median durations of complete remission and survival were […]

Molecular characterization of Coriolus versicolor PSP-induced apoptosis in human promyelotic leukemic HL-60 cells using cDNA microarray.

Proteins and peptide bound polysaccharides (PSP) extracted from Basidiomycetous fungi are widely used in cancer immunotherapy and recently demonstrated to induce apoptosis in cancer cells in vitro. In order to provide the molecular pharmacological mechanisms of PSP on human cancer cells, we investigated the gene expression profiles of PSP-treated apoptotic human promyelotic leukemic HL-60 cells using ResGen 40k IMAGE printed cDNA microarray. In total 378 and 111 transcripts were identified as differentially expressed in the apoptotic cells by at least a factor of 2 or 3, respectively. Our data show that PSP-induced apoptosis in HL-60 cells might be mediated by up-regulation of early transcription factors such as AP-1, EGR1, IER2 and IER5, and down-regulation of NF-kappaB transcription pathways. Other gene expression changes, including the increase of several apoptotic or anti-proliferation genes, such as GADD45A/B and TUSC2, and the decrease of a batch of phosphatase and kinase genes, may also provide further evidences in supporting the process of PSP induced apoptosis in cancer cells. Some of the well-characterized carcinogenesis-related gene transcripts such as SAT, DCT, Melan-A, uPA and cyclin E1 were also alternated by PSP in the HL-60 cells. These transcripts can be employed as markers for quality control of PSP products on functional levels. The present study provides new insight into the molecular mechanisms involved in PSP-induced apoptosis in leukemic HL-60 cells analyzed by cDNA microarray.[…]

Coriolus versicolor (Yunzhi) extract attenuates growth of human leukemia xenografts and induces apoptosis through the mitochondrial pathway.

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.[…]