Enhanced induction of lymphokine-activated killer activity after lentinan administration in patients with gastric carcinoma

Immunomodulatory Properties of Polysaccharides from Lentinula edodes

Lentinula edodes (Berk.) Pegler, also known as shiitake mushroom, is a popular edible macrofungus and a source of numerous bioactive substances with multiple beneficial health effects. L. edodes-derived polysaccharides are the most valuable compounds, with anticancer, antioxidant, antimicrobial, and immunomodulatory properties. It has been demonstrated that their biological activity depends on the extraction method, which affects monosaccharide composition, molecular weight, branching degrees, and helical conformation. In this review, we discuss the immunomodulatory properties of various polysaccharides from L. edodes in animal models and in humans.

Preparation, characterisation and anti-tumour activity of Ganoderma lucidum polysaccharide nanoparticles

OBJECTIVES

The aim was to prepare novel Ganoderma lucidum polysaccharide nanoparticles and to evaluate the physicochemical properties and anti-tumour activity in in-vitro cytotoxicity studies using HepG2, HeLa and A549 cancer cell lines, and growth promotion effects on mouse spleen cells.

METHODS

Chitosan nanoparticles loaded with G. lucidum polysaccharide were prepared using the ion-revulsion method. The diameter distribution of the particles and the surface charge were measured using a zetasizer analyser. The entrapment efficiency and drug loading capacity were examined by the diethylaminoethanol weak anion exchange method. The cytotoxic effects of nanoparticles on tumour cells and the growth promotion effects on mouse spleen cells were tested using the MTT assay.

KEY FINDINGS

Nanoparticles loaded with G. lucidum polysaccharide at 6 microg/ml and chitosan/sodium tripolyphosphate (mass) ratio of 5.5 had significantly greater cytotoxic effects on tumour cells and growth promotion effects on mouse spleen cells than empty nanoparticles.

CONCLUSIONS

G. lucidum polysaccharide nanoparticles showed significant anti-tumour efficacy, having both cytotoxic effects on tumour cells and growth promotion effects on spleen cells, making it a promising candidate in the clinical setting.

Dietary supplementation with white button mushroom enhances natural killer cell activity in C57BL/6 mice

Mushrooms are reported to possess antitumor, antiviral, and antibacterial properties. These effects of mushrooms are suggested to be due to their ability to modulate immune cell functions. However, a majority of these studies evaluated the effect of administering extracts of exotic mushrooms through parental routes, whereas little is known about the immunological effect of a dietary intake of white button mushrooms, which represent 90% of mushrooms consumed in the U.S. In this study, we fed C57BL/6 mice a diet containing 0, 2, or 10% (wt/wt) white button mushroom powder for 10 wk and examined indices of innate and cell-mediated immunity. Mushroom supplementation enhanced natural killer (NK) cell activity, and IFNgamma and tumor necrosis factor-alpha (TNFalpha) production, but only tended to increase IL-2 (P = 0.09) and did not affect IL-10 production by splenocytes. There were significant correlations between NK activity and production of IFNgamma (r = 0.615, P < 0.001) and TNFalpha (r = 0.423, P = 0.032) in splenocytes. Mushroom supplementation did not affect macrophage production of IL-6, TNFalpha, prostaglandin E(2), nitric oxide, and H(2)O(2), nor did it alter the percentage of total T cells, helper T cells (CD4(+)), cytotoxic or suppressive T cells (CD8(+)), regulatory T cells (CD4(+)/CD25(+)), total B cells, macrophages, and NK cells in spleens. These results suggest that increased intake of white button mushrooms may promote innate immunity against tumors and viruses through the enhancement of a key component, NK activity. This effect might be mediated through increased IFNgamma and TNFalpha production.

Herbs or natural products that decrease cancer growth part one of a four-part series

PURPOSE/OBJECTIVES

To provide evidence-based research information about 31 herbs and natural products that have shown potential in early research to decrease cancer growth or as adjuncts with cancer treatment.

DATA SOURCES

Names of herbs and natural products with potential to decrease cancer growth have been selected from listings in the Natural Medicines Comprehensive Database and Lawrence Review of Natural Products-Monograph System. Information about these herbs has been found in evidence-based studies cited in references.

DATA SYNTHESIS

In preliminary studies, 31 herbs and natural products appear to have potential for cancer treatment.

CONCLUSIONS

This preliminary evidence may be useful to healthcare professionals and patients with cancer.

IMPLICATIONS FOR NURSING

The information in this article is designed to provide quick access for healthcare professionals working in clinical oncology. Oncology nurses who have this information can become resources for patients and other healthcare professionals.

Pilot study of a specific dietary supplement in tumor-bearing mice and in stage IIIB and IV non-small cell lung cancer patients

Previously, a specific dietary supplement, selected vegetables (SV), was found to be associated with prolonged survival of stage III and IV non-small cell lung cancer (NSCLC) patients. In this study, several anticancer components in SV were measured; the anticancer activity of SV was assessed using a lung tumor model, line 1 in BALB/c mice. SV was also used in conjunction with conventional therapies by stage IIIB and IV NSCLC patients whose survival and clinical responses were evaluated. A daily portion (283 g) of SV was found to contain 63 mg of inositol hexaphosphate, 4.4 mg of daidzein, 2.6 mg of genistein, and 16 mg of coumestrol. Mouse food containing 5% SV (wt/wt) was associated with a 53-74% inhibition of tumor growth rate. Fourteen of the 18 patients who ingested SV daily for 2-46 months were included in the analyses; none showed evidence of toxicity. The first lead case remained tumor free for > 133 months; the second case showed complete regression of multiple brain lesions after using SV and radiotherapy. The median survival time of the remaining 12 patients was 33.5 months, and one-year survival was > 70%. The median survival time of the 16 "intent-to-treat" patients (including ineligible patients) was 20 months, and one-year survival was 55%. The Karnofsky performance status of eligible patients was 55 +/- 13 at entry but improved to 92 +/- 9 after use of SV for five months or longer (p < 0.01). Five patients had stable lesions for 30, 30, 20, 12, and 2 months; two of them, whose primary tumor was resected, used SV alone and demonstrated an objective response of their metastatic tumors. In addition to the two lead cases, eight patients had no new metastases after using SV. Three patients had complete regression of brain metastases after using radiotherapy and SV. In this study, daily ingestion of SV was associated with objective responses, prolonged survival, and attenuation of the normal pattern of progression of stage IIIB and IV NSCLC. A large randomized phase III clinical trial is needed to confirm the results observed in this pilot study.

Phase I/II study of stage III and IV non-small cell lung cancer patients taking a specific dietary supplement

This phase I/II study evaluates the influence of selected vegetables (SV) that contain known antitumor components on the survival of stage III-IV non-small cell lung cancer (NSCLC) patients. All patients were treated with conventional therapies. SV was added to the daily diet of 5 stage I patients in the toxicity study group (TG) and 6 stage III and IV patients in the treatment group (SVG), but not to the diet of 13 stage III and IV patients in the control group (CG). Age, Karnofsky performance status (KPS), and body mass index of SVG and CG patients were comparable at entry. KPS declined in the CG patients (79 +/- 8 to 55 +/- 11) but improved in the SVG patients (75 +/- 8 to 80 +/- 13) one to three months after entry. Weight change in the CG, SVG, and TG patients was -12 +/- 5%, -2 +/- 2%, and +4 +/- 4%, respectively. The median survival time and mean survival of the CG patients were 4 and 4.8 months, but in the SVG patients they were 15.5 and 15 months (p < 0.01). No clinical signs of toxicity were found in the TG patients in the 24-month study period. Adding SV to the daily diet of NSCLC patients was found to be nontoxic and associated with improved weight maintenance, KPS, and survival of stage III and IV NSCLC patients.

The preoperative administration of lentinan ameliorated the impairment of natural killer activity after cardiopulmonary bypass

The aim of this study was to determine whether the preoperative administration of lentinan, which is used clinically to activate T cell function in cancer patients, prevents the impairment of lymphocyte function after cardiopulmonary bypass (CPB). A total of 25 adults undergoing coronary artery bypass grafting were enrolled in this study. Lentinan (2 mg) was given to 10 randomly selected patients 7 d before surgery, while the other 15 patients were considered as a control. The white blood cell count, percentage of lymphocytes, subsets of lymphocytes, and natural killer cell activity were measured preoperatively, immediately after CPB and 1, 3, and 6 d after surgery. The white blood cell counts and the percentage of lymphocytes were not significantly different between the two groups; however, the percentage of CD4-positive cells in the lentinan group recovered to normal more rapidly than in the control group. Although natural killer cell activity was impaired in the control group after CPB, it maintained a nearly normal level in the lentinan group. The preoperative administration of lentinan for patients undergoing CPB ameliorated the impairment of natural killer activity and promoted the rapid recovery of CD4-positive cells.

Monocyte function associated with intermittent lentinan therapy after resection of gastric cancer

The effect of lentinan administration on monocyte function in the peripheral blood were examined in 33 patients who underwent resection of gastric cancer. As parameters of monocyte function, IL-1 production, C3b receptor, Fc gamma receptor and monocyte ratio were determined every 4 weeks for a maximum of 24 weeks. Among patients who were taking combined therapy with lentinan, an increase in IL-1 beta production of more than 50% was found 8 weeks (2 months) after the initiation of therapy in 8 of 12 patients given 2 mg at 2-week intervals, and in 11 of 16 patients given the same dose at 4-week intervals. This increase was particularly clear in stage II or more advanced cases. There were no significant changes in the other parameters studied. It has been considered that lentinen is effective when administered once a week. The results of the present study, however, suggest that lentinan given every 4 weeks also stimulates monocyte function enough to maintain immunological activity.

Effects of intraportal administration of chemoimmunotherapeutic agents on natural killer cell activity in the rat liver

To evaluate the effects of continuous intraportal chemotherapy on tumor immunity of the liver, natural killer (NK) cell activity was estimated in the rat liver. In an in vitro study, NK-enriched mononuclear cells collected from rat liver were incubated with 5-fluorouracil (5-FU) alone and with a 5-fluorouracil/mitomycin C (5-FU/MMC) combination at different concentrations. NK activity was measured after 24-hour incubation. In an in vivo study, the continuous intraportal administration of chemotherapeutic (5-FU/MMC) and chemoimmunotherapeutic (5-FU/MMC/lentinan) agents was carried out in rats for 5 days, and NK-enriched mononuclear cells were then collected from the liver for the measurement of NK activity. Neither 5-FU alone nor the 5-FU/MMC combination affected NK activity in vitro. In the in vivo study, however, the 5-FU/MMC combination significantly decreased NK activity, and the addition of lentinan recovered the activity to the control level. It can thus be concluded that the intraportal administration of chemotherapeutic agents reduces NK activity in the liver and the addition of an immunostimulator to such agents prevents this reduction.

Application of chemical immunomodulators to the treatment of cancer and AIDS

A number of potential advantages, development of promising new agents, and the discovery of synergy with cytokines or cell products continue to spur research into the application of chemical immunomodulators for the treatment of cancer and AIDS. In preclinical in vitro and in vivo systems, chemical immunomodulators definitely modulate the immune system and have therapeutic efficacy. Although clinical trials have shown the ability of these agents to modulate the human immune system, thus far chemical immunomodulators have generally not fulfilled the therapeutic promise generated in animal models for the treatment of human diseases. While the discrepancy in results between animal models and human trials is obvious, the basis is not apparent. Species differences in elimination kinetics, presentation of active drug at the site of action, and the development of tachyphylaxis have been postulated as reasons for the minimal activity of these agents in humans. In addition, the use of investigational techniques established for cytotoxic agents may not be appropriate for immunomodulators. As with any immunomodulator, determining an optimal immunostimulatory dose and schedule and applying the therapy to patients with minimal tumor burden would perhaps be more appropriate than use of a maximally tolerated dose in patients with advanced disease. A dose-immunological effect relationship has recently been demonstrated for levamisole at doses higher than those used for many years in levamisole trials (99). While research and clinical investigation have identified several potentially useful chemical immunomodulators, the elementary understanding of the biochemical mechanisms involved in immunoregulation remains basic. Future research must elucidate these mechanisms, particularly in humans, to maximize the benefits of chemical immunomodulators as single agents or combined with cytotoxic chemotherapeutic agents, surgery, radiation therapy, other immunomodulators, and antiviral agents.