Significant prolongation of disease-free period gained by oral polysaccharide K (PSK) administration after curative surgical operation of colorectal cancer

Coriolus (Trametes) versicolor mushroom to reduce adverse effects from chemotherapy or radiotherapy in people with colorectal cancer

BACKGROUND

Radiotherapy and chemotherapy are used to improve survival in colorectal cancer but adverse effects can be a problem. Severe adverse effects may result in dose reduction or cessation of treatment, which have an impact on survival. Coriolus versicolor (Trametes versicolor or 'Turkey Tail') mushroom and its extracts have been used by cancer patients to help with adverse effects.

OBJECTIVES

To assess the effects of adjunctive Coriolus versicolor (Trametes versicolor) and its extracts on adverse effects and on survival during colorectal cancer treatment (chemotherapy and radiotherapy) compared with no adjunctive treatment.

SEARCH METHODS

We searched databases including CENTRAL, MEDLINE, Embase, AMED and CINAHL, Chinese and Japanese databases, and trials registers to 12th April 2022 without restriction of language or publication status. We screened reference lists and attempted to contact researchers in the field to identify additional studies.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) investigating the efficacy and safety of Coriolus versicolor and its extracts in adult participants with a confirmed diagnosis of colorectal cancer, in addition to conventional treatment. Interventions included any preparation of Coriolus versicolor (raw, decoction, capsule, tablet, tincture, extract, injection), any part of the fungus (cap, stem, mycelium or whole), in any dose or regimen. Outcomes included adverse events rates, survival, disease progression and recurrence, response rates and quality of life.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened and selected studies, extracted outcome data, and assessed risk of bias. We evaluated the overall certainty of evidence using the GRADE approach.

MAIN RESULTS

We included seven parallel RCTs (1569 participants). Six studies (1516 participants) were conducted in Japan and one study (53 participants) in China. Studies included both male and female participants with colorectal cancer (five studies), colon cancer (one study) or rectal cancer (one study). Participants were diagnosed with cancer ranging from stage II to stage IV. Coriolus was used in the form of an extract in all seven studies and was generally used after curative resection, although in one study it was used preoperatively. Duration of treatment with the extract varied between four weeks and three years. Chemotherapeutic regimens in six studies consisted of an oral fluoropyrimidine which was preceded by weekly intravenous 5-Fluorouracil (5-FU) in one study, by mitomycin C in two studies, and which was combined with folinic acid (Leucovorin) in two studies and with radiotherapy preoperatively in one study. XELOX (oxaliplatin intravenous infusion and capecitabine) was used in the remaining study. We found very low-certainty evidence of little to no effect of adjunctive treatment with Coriolus (in the form of an extract, polysaccharide-Krestin, PSK) on withdrawal from treatment due to adverse events  (risk ratio (RR) 1.03, 95% confidence interval (CI) 0.45 to 2.34; 703 participants; 3 studies;). We are uncertain whether adjunctive Coriolus versicolor and its extracts compared to usual care alone resulted in a difference in adverse events including neutropenia (RR 0.41, 95% CI 0.24 to 0.71; 133 participants; 3 studies; very low certainty), oral cavity disorders such as oral dryness and mucositis (RR 0.37, 95% CI 0.13 to 1.03; 1022 participants; 5 studies; very low certainty), nausea (RR 0.73, 95% CI 0.44 to 1.22; 969 participants; 4 studies; very low certainty), diarrhoea (RR 0.77, 95% CI 0.32 to 1.86; 1022 participants; 5 studies; very low certainty), and fatigue (RR 0.76; 95% CI 0.33 to 1.78; 133 participants; 3 studies; very low certainty). We found low-certainty evidence of a small effect of adjunctive Coriolus on improved survival at five years compared with no adjunctive care (RR 1.08, 95% CI 1.01 to 1.15; 1094 participants; 3 studies; number needed to benefit (NNTB) = 16 (95% Cl 9 to 70). The effect at earlier time points was unclear.

AUTHORS' CONCLUSIONS

Due to the very low certainty of evidence, we were uncertain about the effect of adjunctive Coriolus (in the form of an extract PSK) on adverse events resulting from conventional chemotherapy for colorectal cancer. This includes effects on withdrawal of treatment due to adverse events and on specific adverse outcomes such as neutropenia and nausea. The uncertainty in the evidence also means that it was unclear whether any adverse events were due to the chemotherapy or to the extract itself. While there was low-certainty evidence of a small effect on overall survival at five years, the influence of reduced adverse effects on this could not be determined. In addition, chemotherapy regimens used in assessing this outcome do not reflect current preferred practice.

Immunoceuticals: Harnessing Their Immunomodulatory Potential to Promote Health and Wellness

Knowledge that certain nutraceuticals can modulate the immune system is not new. These naturally occurring compounds are known as immunoceuticals, which is a novel term that refers to products and systems that naturally improve an individual’s immuno-competence. Examples of immunoceuticals include vitamin D3, mushroom glycans, flavonols, quercetin, omega-3 fatty acids, carotenoids, and micronutrients (e.g., zinc and selenium), to name a few. The immune system is a complex and highly intricate system comprising molecules, cells, tissues, and organs that are regulated by many different genetic and environmental factors. There are instances, such as pathological conditions, in which a normal immune response is suboptimal or inappropriate and thus augmentation or tuning of the immune response by immunoceuticals may be desired. With infectious diseases, cancers, autoimmune disorders, inflammatory conditions, and allergies on the rise in both humans and animals, the importance of the use of immunoceuticals to prevent, treat, or augment the treatment of these conditions is becoming more evident as a natural and often economical approach to support wellness. The global nutraceuticals market, which includes immunoceuticals, is a multi-billion-dollar industry, with a market size value of USD 454.55 billion in 2021, which is expected to reach USD 991.09 billion by 2030. This review will provide an overview of the immune system, the importance of immunomodulation, and defining and testing for immunocompetence, followed by a discussion of several key immunoceuticals with clinically proven and evidence-based immunomodulatory properties.

Practical Application of "About Herbs" Website: Herbs and Dietary Supplement Use in Oncology Settings

The Integrative Medicine Service at Memorial Sloan Kettering Cancer Center developed and maintains About Herbs (www.aboutherbs.com), which provides summaries of research data including purported uses, adverse effects, and herb-drug interactions for about 284 dietary supplements. Using Google Analytics, we found the website registered more than 26,317,000 hits since November 2002. The 10 most searched-for herbs/supplements of 2018 are chaga mushroom, turmeric, ashwagandha, reishi mushroom, graviola, Active Hexose-Correlated Compound, boswellia, dandelion, green tea, and Coriolus versicolor. Here we discuss their safety, herb-drug interactions, and appropriate uses in the oncology setting, based on literature searches in PubMed. Over the past 16 years, the evidence for use of these supplements is based mostly on preclinical findings, with few well-designed studies and limited trials conducted in cancer patients. It is important to familiarize health care professionals about popular supplements, so patients can be informed to make decisions that maximize benefits and minimize risks.

Fungal microbiome in colorectal cancer: a systematic review

Colorectal cancer (CRC) is the third cause of cancer-related death worldwide. It has been estimated that more than one million new cases occur every year. Several studies have investigated the role of host bacteria as agents protecting against or increasing the risk of CRC, but few have assessed the fungal microbiome in patients with CRC. Fungal dysbiosis has been studied in colorectal diseases (e.g. inflammatory bowel diseases), but few researches compared the fungal microbiome of CRC patients with those of controls. The current study represents a systematic review aimed at assessing the expression and diversity of fungi in patients with CRC and non-CRC individuals. Here, we discuss the fungal species that could be implied in CRC development and alterations that can be induced by the presence of CRC, and the potential implications for future research.

Coriolus Versicolor and Ganoderma Lucidum Related Natural Products as an Adjunct Therapy for Cancers: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Background: Cancer incidence and mortality rates keep rising globally. Coriolus versicolor and Ganoderma lucidum related natural products are commonly applied as a complementary therapeutic option for different stages and types of cancers. The aim of this study is to evaluate the efficacy and safety of the products for cancer therapy. Methods: Randomized controlled trials were identified by systematic search over seven databases from inceptions to May 10, 2019. Two independent reviewers extracted data and assessed the study quality. Meta-analyses were performed to pool hazard ratio (HR), risk ratio (RR), mean differences (MD), and 95% CI using random-effects models. The sources of heterogeneity were explored by subgroup analyses and sensitivity analyses. Publication bias was detected by Funnel plots, Begg's test, and Egger's test. Results: Twenty-three trials involving 4,246 cancer patients were included in this work. C. versicolor and G. lucidum related natural products were significantly associated with lower risks of mortality (HR: 0.82; 95% CI: 0.72, 0.94) and higher total efficacy (RR: 1.30; 95% CI: 1.09, 1.55), but not associated with control rate (RR: 1.05; 95% CI: 0.96, 1.14) compared with control treatment. There was no significant difference between C. versicolor related natural products and control treatment in the effect on relapse-free survival (HR: 1.19; 95% CI: 0.91, 1.55). Compared with control treatment, C. versicolor and G. lucidum related natural products had a favorable effect on elevated levels of CD3 (MD: 9.03%; 95% CI: 2.10, 16.50) and CD4 (MD: 9.2%; 95% CI: 1.01, 17.39), but had no effect on the levels of CD8 (MD: -5.52%; 95% CI: -23.17, 12.13), CD4/CD8 (MD: 0.73; 95% CI:-0.45, 1.91), or NK(MD: 5.87%; 95% CI: -1.06, 12.8). Conclusion: In this meta-analysis, we found that C. versicolor and G. lucidum related natural products might have potential benefits on the overall survival and quality of life in cancer patients.

Poly(d,l-lactide-co-glycolide) Nanoparticles as Delivery Platforms for TLR7/8 Agonist-Based Cancer Vaccine

Targeted drug delivery can significantly influence the efficacy of a drug. In the past decades, diverse drug-delivery technologies, including nano- and microparticles, co-crystals, and microneedles have been developed to maximize therapeutic efficacy and minimize undesired side effects of therapeutics. Nanoparticles-submicron-sized drug carriers-have been actively investigated for the delivery of antibiotics, nucleic acids, peptide/proteins, and chemotherapeutics. Recently, nanoparticles have gained attention as a vaccine delivery platform for tumor-associated antigens (TAAs) and/or vaccine adjuvants. Agonists of imidazoquinoline-based Toll-like receptor (TLR) 7/8 are potent cytokine inducers that are used as cancer vaccine adjuvants to elicit robust T-cell response by activating dendritic cells (DCs). Despite their in vitro potency, the translation of TLR7 agonists as cancer vaccine adjuvants in the clinic has been limited by their poor retention at the injection site. Therefore, a formulation that could improve the availability of TLR7/8 agonists to DCs via conventional vaccine administration routes (subcutaneous, intramuscular) can broaden the application of TLR7/8 agonists for cancer immunotherapy. Polymeric nanoparticles fabricated with poly(d,l-lactide-co-glycolide) (PLGA) can be an efficient TLR7/8 agonist delivery platform. PLGA is a biocompatible polymer, and nanoparticles prepared from this polymer are stable in saline and are small enough to be administered by subcutaneous or intramuscular injections. Furthermore, nanoparticulate TLR7/8 delivery can enhance DC uptake and facilitate lymphatic drainage, both of which can enhance the adjuvanticity of TLR7/8 agonists compared with soluble forms. In this review, we discuss the use of PLGA nanoparticles with TLR7/8 agonists for improving cancer immunotherapy.

Can polysaccharide K improve therapeutic efficacy and safety in gastrointestinal cancer? a systematic review and network meta-analysis

Objective

To assess the comparative efficacy and safety of polysaccharide K (PSK), with or without chemotherapy, for patients with gastrointestinal cancer (GIC) through a systematic review and network meta-analysis.

Materials and Methods

We performed a network meta-analysis to identify evidence from randomized controlled trials. We searched PubMed, Embase and the Cochrane Library for publications up to May 2017. The prespecified primary efficacy outcomes were 1–7 year overall survival (OS), while the secondary efficacy outcomes were 1–7 year disease-free survival (DFS); we performed subgroup analyses and meta-regressions according to the cancer type (colorectal, esophagus and gastric cancer) and treatment arms (with or without chemotherapy). Safety outcomes were side effects of PSK. We conducted pairwise meta-analyses using a random-effects model and then performed random-effects network meta-analyses.

Results

A total of 23 trials were eligible, involving 10684 patients and 13 intervention arms. PSK treatment significantly increased 1–5 year OS and resulted in positive trends in 6–7 year OS; significant increases were also found in 1–7 year DFS, while no increase in side effects was observed. Significant efficacy outcomes obvious in colorectal and gastric cancer groups, as well as PSK combined with chemotherapy groups (iv, po, iv+po). Network meta-analysis revealed that PSK combined with chemotherapy was superior, with significantly increased 3-year and 5-year OS. The study is registered with PROSPERO (CRD42017065193)

Conclusions

The adjuvant immunochemotherapy agent PSK is effective and safe for patients with GIC. PSK combined with chemotherapy appears to be the preferred application of PSK.

Phase III trial comparing UFT + PSK to UFT + LV in stage IIB, III colorectal cancer (MCSGO-CCTG)

PURPOSE

Oral adjuvant uracil and tegafur plus leucovorin (UFT/LV) is not inferior to standard weekly fluorouracil and folinate for stage II/III colon cancer. However, protein-bound polysaccharide K (PSK) has been evaluated as postoperative adjuvant therapy for colorectal cancer. This report is the first of MCSGO-CCTG, which compared UFT/LV to UFT/PSK as adjuvant chemotherapy for stage IIB or III colorectal cancer in patients who had undergone Japanese D2/D3 lymph node dissection.

METHODS

The primary endpoint was the 3-year disease-free survival (DFS). A randomized non-inferiority study compared UFT/LV to UFT/PSK. The overall survival, adverse events, compliance, and quality of life were also investigated as the secondary endpoints.

RESULTS

Between March 2006 and December 2010, 357 patients were randomized to UFT/PSK (n = 178) or UFT/LV (n = 179) (median age 65 years, colon/rectum 67.4/32.6%, stage IIB/IIIA/IIIB/IIIC 11.1/15.7/55.0/18.2%). The 3-year DFS rate was 82.3% in those receiving UFT/LV and 72.1% in those receiving UFT/PSK. The non-inferiority of UFT/PSK adjuvant therapy to UFT/LV therapy was not verified (-9.06%, 90% confidence interval -17.06 to -1.06%). The 3-year overall survival rate was 95.4% in those receiving UFT/LV and 90.7% in those receiving UFT/PSK.

CONCLUSIONS

As adjuvant chemotherapy for stage IIB and III colorectal cancer patients, UFT/PSK adjuvant therapy was not non-inferior to UFT/LV therapy with respect to the DFS.

Leccinum vulpinum Watling induces DNA damage, decreases cell proliferation and induces apoptosis on the human MCF-7 breast cancer cell line

The current work aimed to study the antitumour activity of a phenolic extract of the edible mushroom Leccinum vulpinum Watling, rich essentially in hydroxybenzoic acids. In a first approach, the mushroom extract was tested against cancer cell growth by using four human tumour cell lines. Given the positive results obtained in these initial screening experiments and the evidence of some studies for an inverse relationship between mushroom consumption and breast cancer risk, a detailed study of the bioactivity of the extract was carried out on MCF-7 cells. Once the selected cell line to precede the work was the breast adenocarcinoma cell line, the human breast non-malignant cell line MCF-10A was used as control. Overall, the extract decreased cellular proliferation and induced apoptosis. Furthermore, the results also suggest that the extract causes cellular DNA damage. Data obtained highlight the potential of mushrooms as a source of biologically active compounds, particularly with antitumour activity.

Recent progress in fungus-derived bioactive agents for targeting of signaling machinery in cancer cells

It is becoming increasingly understood that tumor cells may have different mutations and dependencies on diverse intracellular signaling cascades for survival or metastatic potential. Overexpression of oncogenes, inactivation of tumor suppressor genes, genetic/epigenetic mutations, genomic instability, and loss of apoptotic cell death are some of the mechanisms that have been widely investigated in molecular oncology. We partition this multicomponent review into the most recent evidence on the anticancer activity of fungal substances obtained from in vitro and xenografted models, and these fungal substances modulate expression of oncogenic and tumor suppressor miRNAs. There are some outstanding questions regarding fungus-derived chemical-induced modulation of intracellular signaling networks in different cancer cell lines and preclinical models. Certain hints have emerged, emphasizing mechanisms via which apoptosis can be restored in TRAIL-resistant cancer cells. Reconceptualization of the knowledge obtained from these emerging areas of research will enable us to potentially identify natural agents with notable anticancer activity and minimal off-target effects. Integration of experimentally verified evidence obtained from cancer cell line gene expression with large-scale functional screening results and pharmacological sensitivity data will be helpful in identification of therapeutics with substantial efficacy. New tools and technologies will further deepen our understanding of the signaling networks that underlie the development of cancer, metastasis, and resistance to different therapeutics at both a personal and systems-wide level.

Polysaccharide K and Coriolus versicolor extracts for lung cancer: a systematic review

BACKGROUND

Polysaccharide K, also known as PSK or Krestin, is derived from the Coriolus versicolor mushroom and is widely used in Japan as an adjuvant immunotherapy for a variety of cancer including lung cancer. Despite reported benefits, there has been no English language synthesis of PSK for lung cancer. To address this knowledge gap, we conducted a systematic review of PSK for the treatment of lung cancer.

METHODS

We searched PubMed, EMBASE, CINAHL, the Cochrane Library, AltHealth Watch, and the Library of Science and Technology from inception to August 2014 for clinical and preclinical evidence pertaining to the safety and efficacy of PSK or other Coriolus versicolor extracts for lung cancer.

RESULTS

Thirty-one reports of 28 studies were included for full review and analysis. Six studies were randomized controlled trials, 5 were nonrandomized controlled trials, and 17 were preclinical studies. Nine of the reports were Japanese language publications. Fifteen of 17 preclinical studies supported anticancer effects for PSK through immunomodulation and potentiation of immune surveillance, as well as through direct tumor inhibiting actions in vivo that resulted in reduced tumor growth and antimetastatic effects. Nonrandomized controlled trials showed improvement of various survival measures including median survival and 1-, 2-, and 5-year survival. Randomized controlled trials showed benefits on a range of endpoints, including immune parameters and hematological function, performance status and body weight, tumor-related symptoms such as fatigue and anorexia, as well as survival. Although there were conflicting results for impact on some of the tumor-related symptoms and median survival, overall most randomized controlled trials supported a positive impact for PSK on these endpoints. PSK was safely administered following and in conjunction with standard radiation and chemotherapy.

CONCLUSIONS

PSK may improve immune function, reduce tumor-associated symptoms, and extend survival in lung cancer patients. Larger, more rigorous randomized controlled trials for PSK in lung cancer patients are warranted.

Immunomodulation of Fungal β-Glucan in Host Defense Signaling by Dectin-1

During the course of evolution, animals encountered the harmful effects of fungi, which are strong pathogens. Therefore, they have developed powerful mechanisms to protect themselves against these fungal invaders. β-Glucans are glucose polymers of a linear β(1,3)-glucan backbone with β(1,6)-linked side chains. The immunostimulatory and antitumor activities of β-glucans have been reported; however, their mechanisms have only begun to be elucidated. Fungal and particulate β-glucans, despite their large size, can be taken up by the M cells of Peyer's patches, and interact with macrophages or dendritic cells (DCs) and activate systemic immune responses to overcome the fungal infection. The sampled β-glucans function as pathogen-associated molecular patterns (PAMPs) and are recognized by pattern recognition receptors (PRRs) on innate immune cells. Dectin-1 receptor systems have been incorporated as the PRRs of β-glucans in the innate immune cells of higher animal systems, which function on the front line against fungal infection, and have been exploited in cancer treatments to enhance systemic immune function. Dectin-1 on macrophages and DCs performs dual functions: internalization of β-glucan-containing particles and transmittance of its signals into the nucleus. This review will depict in detail how the physicochemical nature of β-glucan contributes to its immunostimulating effect in hosts and the potential uses of β-glucan by elucidating the dectin-1 signal transduction pathway. The elucidation of β-glucan and its signaling pathway will undoubtedly open a new research area on its potential therapeutic applications, including as immunostimulants for antifungal and anti-cancer regimens.

Crude dietary polysaccharide fraction isolated from jackfruit enhances immune system activity in mice

Crude polysaccharides (PSs) were isolated from the fruit pulp of jackfruit, and their chemical composition determined and evaluated for an immune regulatory activity in mice. The PSs were isolated from water extracts of jackfruit pulp (JFP) using the ethanol precipitation method. The resulting precipitates were further purified by dialysis and protein depletion by the Sevage method. The phenol-sulfuric method was used to determine the content of the PSs. The composition of PSs was determined by the Sephadex-G200 column chromatography and high-performance liquid chromatography methods. The thymus index and macrophage phagocytic function methods in mice were used to evaluate the immune regulatory activity of JFP-PSs. The JFP-PSs content in jackfruit was about 21% (w/w) and the yield of crude PSs was 3.91%. The single molecular mass weight PS was the main constituent of JFP-PSs. The major monosaccharide residues were rhamnose, glucose, galactose, and arabinose. The JFP-PSs enhanced the thymus weight index and the phagocytic rate after 30 days of subchronic p.o. administration to mice at 4.5 mg/kg. The JFP contains single molecular PS and JFP-PS has immune-stimulating activities in mice. These data suggest that at least some of the traditional uses of JFP can be ascribed to its immunomodulatory effects.

Ganoderma lucidum spore induced CA72-4 elevation in gastrointestinal cancer: a five-case report

GANODERMA LUCIDU

spore (GLS), an over-the-counter herbal supplement, is widely used by cancer patients in China. Although preclinical studies have shown it to be safe, complete safety data on GLS is still lacking. In this article, we report 5 cases of gastrointestinal cancer that were treated with GLS plus multiple strategies between 2010 and 2011. These patients presented with increased levels of the serum tumor marker CA72-4, one of the most valuable markers for monitoring therapeutic response in patients receiving gastrointestinal cancer treatment, after oral ingestion of GLS twice a day for 1 or 2 months. Interestingly, CA72-4 rapidly returned to normal levels when the patients discontinued the supplement and no change in clinical symptoms accompanied the CA72-4 surge. Taking into consideration that the underlying mechanism of this reaction is obscure, we suggest that additional studies are urgently needed and GLS be used with caution in cancer patients.

Gamma delta T cells are activated by polysaccharide K (PSK) and contribute to the anti-tumor effect of PSK

Polysaccharide K (PSK) is a widely used mushroom extract that has shown anti-tumor and immunomodulatory effects in both preclinical and clinical studies. Therefore, it is important to understand the mechanism of actions of PSK. We recently reported that PSK can activate toll-like receptor 2 and enhances the function of NK cells. The current study was undertaken to study the effect of PSK on gamma delta (γδ) T cells, another important arm of the innate immunity. In vitro experiments using mouse splenocytes showed that γδ T cells produce IFN-γ after treatment with PSK and have up-regulated expression of CD25, CD69, and CD107a. To investigate whether the effect of PSK on γδ T cells is direct or indirect, purified γδ T cells were cultured either alone or together with bone marrow-derived DC in a co-culture or trans-well system and then stimulated with PSK. Results showed that direct cell-to-cell contact between γδ T cells and DC is required for optimal activation of γδ T cells. There was also reciprocal activation of DC by PSK-activated γδ T cells, as demonstrated by higher expression of costimulatory molecules and enhanced production of IL-12 by DC in the presence of γδ T cells. PSK can also co-stimulate γδ T cells with anti-TCR and anti-CD3 stimulation, in the absence of DC. Finally, in vivo treatment with PSK activates γδ T cells among the tumor infiltrating lymphocytes, and depleting γδ T cells during PSK treatment attenuated the anti-tumor effect of PSK. All together, these results demonstrated that γδ T cells are activated by PSK and contribute to the anti-tumor effect of PSK.

The expression of integrins is decreased in colon cancer cells treated with polysaccharide K

Polysaccharide K (PSK), a protein-bound polysaccharide used as a non-specific immunotherapeutic agent, is said to improve the prognosis of malignant tumors such as colon cancer, but there have been few in‑depth investigations of its mechanism of action. In the present study, we investigated which genes in colon cancer cells themselves are regulated by PSK and what sort of action it exerts. Colon cancer cells were exposed to PSK in vitro and changes to their morphology and adhesive capacity were investigated, as were the changes in integrin expression that occurred. Exposure to PSK caused colon cancer cells to become spherical in morphology and investigation of their adhesion rate showed that it reduced adhesion to laminin, fibrinogen, collagen IV, collagen I and fibronectin. In terms of changes to molecules on the surface of cancer cells, there was reduced expression of integrin mRNA α and β, which are ligands for the proteins of basement membrane. An investigation of the adhesiveness of PSK-stimulated colon cancer cells to vascular endothelial cells also showed that the adhesion rate decreased significantly compared with cells not exposed to PSK. Suppression of integrin expression on the cell surface and reduced adhesion to vascular endothelial cells were observed as a novel mechanism of action of PSK on colon cancer cells.

Anti-metastatic effect of polysaccharide isolated from Colocasia esculenta is exerted through immunostimulation

In the present study, an edible corm of the plant Colocasia esculenta, commonly known as Taro was extracted with cold water (4˚C). Finally, 10.44 g (1.04%) of the crude polysaccharide (Taro-0) was obtained from Taro. The purified active compound (Taro-4-I) was isolated using DEAE-Sepharose FF and Sephadex G-100. The anti-complementary activity of Taro-4-I (57.3±4.5%) was similar to that of polysaccharide K (used as the positive control). The molecular weight of Taro-4-I was 200 kDa and it was a polysaccharide composed of 64.4% neutral sugars and 35.6% uronic acid. Taro-4-I activated the complement system through the classical and alternative pathways. The treatment of peritoneal macrophages with Taro-4-I significantly increased the production of interleukin (IL)-6 and tumor necrosis factor-α (TNF-α) in a dose-dependent manner. However, IL-12 production showed maximal activity at 56 µg/ml and subsequently decreased. Splenocytes obtained from mice which were administered Taro-4-I intravenously showed a higher toxicity to Yac-1 cells compared to those obtained from untreated mice in a effector‑to‑target (E/T) ratio-dependent manner. The group treated with 50 µg/ml Taro-4-I showed a significantly increased toxicity to Yac-1 cells compared to the group treated with 500 µg/ml Taro-4-I. The administration of Taro-4-I significantly inhibited the lung metastasis of B16BL6 melanoma cells. However, the group treated with 50 µg/mouse Taro-4-I had a significantly lower number of tumors compared to the group injected with 500 µg/mouse Taro-4-I.

Polysaccharide K suppresses angiogenesis in colon cancer cells

The protein-bound polysaccharide K (PSK) is used as a non-specific immunotherapeutic agent for the treatment of colon cancer. Little research, however, has been conducted on its association with angiogenesis, which is a prognostic factor markedly correlated with hematogenous metastases. We therefore decided to investigate the action of PSK on angiogenic growth factors, angiogenesis inhibitors and angiogenesis in colon cancer cells. Reverse transcription-polymerase chain reaction (RT-PCR) was used to investigate changes in HIF-1α mRNA expression. PCR array was used to investigate changes in angiogenic growth factors and angiogenesis inhibitors, as well as the expression of related genes. Colon cancer cells were cultured with or without PSK for 48 h. The following day, cells were cultured for two days at 37°C in new complete media. The resulting culture medium was placed in the chamber of a tube formation system in order to investigate tube formation. Investigation of HIF-1α mRNA expression in colon cancer cell lines and in cells cultured under identical conditions with added PSK revealed a significant decrease in expression, as well as a decrease in angiogenic growth factors and related genes in PSK-treated colon cancer cell lines. By contrast, levels of angiogenesis inhibitors and related genes were higher in the PSK-treated colon cancer cell lines. Investigation of tube formation revealed that elongation was inhibited in the medium of the PSK-treated colon cancer cell lines in comparison to the medium of the non-treated colon cancer cell lines. PSK suppresses angiogenic growth factors and related genes, enhances angiogenesis inhibitors and related genes and ultimately suppresses angiogenesis in colon cancer cells.

Biological mechanism and clinical effect of protein-bound polysaccharide K (KRESTIN(®)): review of development and future perspectives

The mechanism of action of protein-bound polysaccharide K (PSK; KRESTIN(®)) involves the following actions: (1) recovery from immunosuppression induced by humoral factors such as transforming growth factor (TGF)-β or as a result of surgery and chemotherapy; (2) activation of antitumor immune responses including maturation of dendritic cells, correction of Th1/Th2 imbalance, and promotion of interleukin-15 production by monocytes; and (3) enhancement of the antitumor effect of chemotherapy by induction of apoptosis and inhibition of metastasis through direct actions on tumor cells. The clinical effectiveness of PSK has been demonstrated for various cancers. In patients with gastric or colorectal cancer, combined use of PSK with postoperative adjuvant chemotherapy prolongs survival, and this effect has been confirmed in multiple meta-analyses. For small-cell lung carcinoma, PSK in conjunction with chemotherapy prolongs the remission period. In addition, PSK has been shown to be effective against various other cancers, reduce the adverse effects of chemotherapy, and improve quality of life. Future studies should examine the effects of PSK under different host immune conditions and tumor properties, elucidate the mechanism of action exhibited in each situation, and identify biomarkers.

Direct inhibition of the transforming growth factor-β pathway by protein-bound polysaccharide through inactivation of Smad2 signaling

Transforming growth factor-β (TGF-β) is involved in the regulation of cell proliferation, differentiation, and apoptosis and is associated with epithelial-mesenchymal transition (EMT). Inhibition of the TGF-β pathway is an attractive strategy for the treatment of cancer. We recently screened for novel TGF-β inhibitors among commercially available drugs and identified protein-bound polysaccharide (PSK) as a strong inhibitor of the TGF-β-induced reporter activity of 3TP-lux, a TGF-β1-responsive luciferase reporter. Protein-bound polysaccharide is used as a non-specific immunostimulant for the treatment of gastric and colorectal cancers in Japan. The anticancer activity of this agent may involve direct regulation of growth factor production and enzyme activity in tumors in addition to its immunomodulatory effect. Although several clinical studies have shown the beneficial therapeutic effects of PSK on various types of tumors, its mechanism of action is not clear. In the present study, Western blot analysis showed that PSK suppressed the phosphorylation and nuclear localization of the Smad2 protein, thereby suggesting that PSK inhibits the Smad and MAPK pathways. Quantitative PCR analysis showed that PSK decreased the expression of several TGF-β pathway target genes. E-cadherin and vimentin immunohistochemistry showed that PSK suppressed TGF-β1-induced EMT, and FACS analysis showed that PSK inhibited the EMT-mediated generation of CD44(+) /CD24(-) cells. These data provide new insights into the mechanisms mediating the TGF-β-inhibiting activity of PSK and suggest that PSK can effectively treat diseases associated with TGF-β signaling.

Polymorphonuclear neutrophils and cancer: intense and sustained neutrophilia as a treatment against solid tumors

Polymorphonuclear neutrophils (PMN) are the most abundant circulating immune cells and represent the first line of immune defense against infection. This review of the biomedical literature of the last 40 years shows that they also have a powerful antitumoral effect under certain circumstances. Typically, the microenvironment surrounding a solid tumor possesses many of the characteristics of chronic inflammation, a condition considered very favorable for tumor growth and spread. However, there are many circumstances that shift the chronic inflammatory state toward an acute inflammatory response around a tumor. This shift seems to convert PMN into very efficient anticancer effector cells. Clinical reports of unexpected antitumoral effects linked to the prolonged use of granulocyte colony-stimulating factor, which stimulates an intense and sustained neutrophilia, suggest that an easy way to fight solid tumors would be to encourage the development of intense peritumoral PMN infiltrates. Specifically designed clinical trials are urgently needed to evaluate the safety and efficacy of such drug-induced neutrophilia in patients with solid tumors. This antitumoral role of neutrophils may provide new avenues for the clinical treatment of cancer.

Immunomodulatory dietary polysaccharides: a systematic review of the literature

BACKGROUND

A large body of literature suggests that certain polysaccharides affect immune system function. Much of this literature, however, consists of in vitro studies or studies in which polysaccharides were injected. Their immunologic effects following oral administration is less clear. The purpose of this systematic review was to consolidate and evaluate the available data regarding the specific immunologic effects of dietary polysaccharides.

METHODS

Studies were identified by conducting PubMed and Google Scholar electronic searches and through reviews of polysaccharide article bibliographies. Only articles published in English were included in this review. Two researchers reviewed data on study design, control, sample size, results, and nature of outcome measures. Subsequent searches were conducted to gather information about polysaccharide safety, structure and composition, and disposition.

RESULTS

We found 62 publications reporting statistically significant effects of orally ingested glucans, pectins, heteroglycans, glucomannans, fucoidans, galactomannans, arabinogalactans and mixed polysaccharide products in rodents. Fifteen controlled human studies reported that oral glucans, arabinogalactans, heteroglycans, and fucoidans exerted significant effects. Although some studies investigated anti-inflammatory effects, most studies investigated the ability of oral polysaccharides to stimulate the immune system. These studies, as well as safety and toxicity studies, suggest that these polysaccharide products appear to be largely well-tolerated.

CONCLUSIONS

Taken as a whole, the oral polysaccharide literature is highly heterogenous and is not sufficient to support broad product structure/function generalizations. Numerous dietary polysaccharides, particularly glucans, appear to elicit diverse immunomodulatory effects in numerous animal tissues, including the blood, GI tract and spleen. Glucan extracts from the Trametes versicolor mushroom improved survival and immune function in human RCTs of cancer patients; glucans, arabinogalactans and fucoidans elicited immunomodulatory effects in controlled studies of healthy adults and patients with canker sores and seasonal allergies. This review provides a foundation that can serve to guide future research on immune modulation by well-characterized polysaccharide compounds.

Polysaccharide krestin is a novel TLR2 agonist that mediates inhibition of tumor growth via stimulation of CD8 T cells and NK cells

PURPOSE

Polysaccharide krestin (PSK) is a mushroom extract that has been long used in Asia and recently in Western countries as a treatment for cancer due to its presumed immune potentiating effects. Although there have been reports of clinical responses after patients have ingested PSK, the mechanism of action of the agent remains undefined. The current study was undertaken to investigate the mechanism of the antitumor actions of PSK.

EXPERIMENTAL DESIGN

The immunostimulatory effect of PSK was first evaluated in vitro using splenocytes from neu transgenic mice and Toll-like receptor (TLR) 2 knockout (TLR2(-/-)) mice. Then the immunostimualtory and antitumor effect of PSK was determined using tumor-bearing neu transgenic mice, TLR2(-/-), and wild-type C57BL/6 mice.

RESULTS

We demonstrate that PSK is a selective TLR2 agonist, and the activation of dendritic cells (DC) and T cells by PSK is dependent on TLR2. Oral administration of PSK in neu transgenic mice significantly inhibits breast cancer growth. Selective depletion of specific cell populations suggests that the antitumor effect of PSK is dependent on both CD8(+) T cell and NK cells, but not CD4(+) T cells. PSK does not inhibit tumor growth in TLR2(-/-) mice suggesting that the antitumor effect is mediated by TLR2.

CONCLUSION

These results demonstrate that PSK, a natural product commonly used for the treatment of cancer, is a specific TLR2 agonist and has potent antitumor effects via stimulation of both innate and adaptive immune pathways.

Protective effects of water-soluble low-molecular-weight β-(1,3-1,6)D-glucan purified from Aureobasidium pullulans GM-NH-1A1 against UFT toxicity in mice

Objectives

5-Fluorouracil and its derivatives are widely used in the treatment of a variety of tumours. However, their use is associated with gastrointestinal toxicity, myelotoxicity and immune toxicity. In this study, we examined the protective effects of low-molecular-weight β-glucan isolated from Aureobasidium pullulans GM-NH-1A1 against toxicity of UFT (combination of tegafur (1-(2-tetrahydrofuryl)-5-fluorouracil) and uracil) in mice bearing colon 26 tumours.

Methods

UFT was administered orally at 50 mg/kg once daily for 14 days alone or with orally administered low-molecular-weight β-glucan, 25, 50 and 100 mg/kg twice daily.

Key findings

Tumour growth was inhibited equally in all treatment groups. Onset of diarrhoea, which started on day 9 of UFT administration, was delayed by concomitant administration of the β-glucan (50 and 100 mg/kg twice daily). Histological analysis showed that damage to small-intestine villi by UFT was inhibited by the orally administered β-glucan.

Conclusions

Oral administration of low-molecular-weight β-glucan prevents gastrointestinal mucositis associated with UFT therapy without interfering with its anti-tumour activity.

Herbs and other botanicals in cancer patient care

OPINION STATEMENT

Non-prescription herbal remedies are commonly used by cancer patients in efforts to control their disease or to manage symptoms associated with cancer and cancer treatments. We address the issues surrounding the use of herbs, herbal compounds, and other botanical agents in the oncology context. Botanicals are biologically active agents that can be useful under appropriate circumstances, but they may be counterproductive when used by patients on chemotherapy or on other prescription medications. Herbs and other botanical agents, despite common public belief, are not benign. They should be understood as unrefined pharmaceuticals, with the capacity to produce physiologic change for better or worse. Indeed, many prescription drugs, chemotherapeutic agents among them, were derived from plants and other natural agents, and the search for additional constituents of plants, animals, and minerals for use as pharmaceutical agents remains an active effort on many fronts. Cautions, appropriate application, and potential utility of botanical agents are discussed below, and sources of reliable information are provided.

Potentiation of histamine release by Microfungal (1-->3)- and (1-->6)-beta-D-glucans

(1-->3)-beta-D-Glucans, a cell wall component in most microfungi, are suggested to play a role in the development of respiratory and general symptoms in organic dust-related diseases. The mechanisms by which they induce these effects are, however, not clear. In the present study, mediator release and its potentiation by the (1-->3)-beta-D-glucan as well as by the (1-->6)-beta-D-glucan found in yeast and other fungi were therefore examined. Blood leucocytes from healthy volunteers and from patients allergic to house dust mite were incubated with (1-->3)-beta-D-glucans with increasing 1,6-branchings: curdlan [a linear (1-->3)-beta-D-glucan], laminarin and scleroglucan, and furthermore with pustulan, a linear (1-->6)-beta-D-glucan. Histamine release was not observed on exposure to the glucans only, but in the presence of anti-immunoglobulin E (IgE) antibody or specific antigens, all the glucans investigated led to an enhancement of the IgE-mediated histamine release. The glucans induced a significant potentiation of the mediator release when present at concentrations in the range of 2-5 x 10(-5) M. These results suggest that (1-->3)-beta-D-glucan as well as (1-->6)-beta-D-glucan aggravates IgE-mediated histamine release. Knowledge concerning the effects of glucans on immune responses may be of importance for understanding and treating inflammatory and allergic diseases.

In vitro and in vivo anti-tumor effects of Astragalus membranaceus

Astragalus membranaceus, a commonly used Chinese medicinal plant, has been shown to be capable of restoring the impaired T cell functions in cancer patients. In this study, the in vitro and in vivo anti-tumor effects of A. membranaceus were investigated. Five bioactive fractions were isolated from the root of A. membranaceus, the fraction designated as AI was found to be the most potent among the five fractions with respect to its mitogenicity on murine splenocytes. Besides investigating the cytostatic effect of AI, its activities on macrophage function, tumor necrosis factor production, induction of lymphokine-activated killer cell and tumor cell differentiation were also examined. The macrophage-like tumors and the myeloid tumors were found to be more sensitive to the cytostatic activity of AI, whereas the fibroblast-like tumors and the mouse Ehrlich ascites tumor appeared to be relatively resistant. Moreover, AI could effectively suppress the in vivo growth of syngeneic tumor in mice. Results showed that murine macrophage pretreated with AI had increased in vitro and in vivo cytostatic activities towards MBL-2 tumor. AI could also act as a priming agent for tumor necrosis factor production in tumor-bearing mice. Preincubation of mouse splenocytes with AI could induce in vitro lymphokine-activated killer-like activity towards WEHI-164 cell. Furthermore, AI was able to induce monocytic differentiation of both human and murine cells in vitro. AI administered in vivo could even partially restore the depressed mitogenic response in tumor-bearing mice. Collectively, the results showed that A. membranaceus could exhibit both in vitro and in vivo anti-tumor effects, which might be achieved through activating the anti-tumor immune mechanism of the host.

Polysaccharide biological response modifiers

Biological response modifiers (BRMs) are substances which augment immune response. BRMs can be cytokines which are produced endogenously in our body by immune cells or derivatives of bacteria, fungi, brown algae, Aloe vera and photosynthetic plants. Such exogeneous derivatives (exogeneous BRMs) can be nucleic acid (CpG), lipid (lipotechoic acid), protein or polysaccharide in nature. The receptors for these exogeneous BRMs are pattern recognition receptors. The binding of exogeneous BRMs to pattern recognition receptors triggers immune response. Exogenous BRMs have been reported to have anti-viral, anti-bacterial, anti-fungal, anti-parasitic, and anti-tumor activities. Among different exogeneous BRMs, polysaccharide BRMs have the widest occurrence in nature. Some polysaccharide BRMs have been tested for their therapeutic properties in human clinical trials. An overview of current understandings of polysaccharide BRMs is summarized in this review.

Efficacy of adjuvant immunochemotherapy with polysaccharide K for patients with curatively resected colorectal cancer: a meta-analysis of centrally randomized controlled clinical trials

The benefits of immunochemotherapy employing the biological response modifier polysaccharide K (PSK) for patients with curatively resected colorectal cancer was reassessed by means of a meta-analysis of data with center randomization from 1,094 patients enrolled in three clinical trials. In all three trials, patients were followed up for at least 5 years after surgery and enrollment of the last patient and outcomes for standard chemotherapy were compared with those for chemotherapy plus PSK. The endpoints were overall survival and disease-free survival; and intent-to-treat analysis was performed without patient exclusion. Data were analyzed using the weighted average of the individual log hazard ratios. The overall survival risk ratio for all eligible patients was 0.71 (95% confidence interval (CI) : 0.55-0.90; P=0.006), and the disease-free survival risk ratio was 0.72 (95% CI: 0.58-0.90; P=0.003). The results of this meta-analysis suggest that adjuvant immunochemotherapy with PSK can improve both survival and disease-free survival of patients with curatively resected colorectal cancer.

Suppressing effects of daily oral supplementation of beta-glucan extracted from Agaricus blazei Murill on spontaneous and peritoneal disseminated metastasis in mouse model

PURPOSE

The Basidiomycete fungus Agaricus blazei Murill has traditionally been used as a health food for the prevention of cancer.

METHODS

We examined whether beta-(1-6)-D: -glucan extracted from A. blazei is a potential anticancer agent in an in vitro and in vivo animal model.

RESULTS

Here we show that (1) beta-glucan had cytotoxic effect against human ovarian cancer HRA cells, but not against murine Lewis lung cancer 3LL cells, in vitro; (2) beta-glucan promotes p38 MAPK activity for suppressing HRA cell proliferation and amplifying the apoptosis cascade; (3) beta-glucan stimulates translocation of the proapoptotic protein, Bax, from the cytosol to mitochondria, cytochrome c release, and subsequent caspase-9 activation; (4) treatment with SB203580, a p38 MAPK-specific inhibitor, suppresses beta-glucan-induced effects, indicating that activation of p38 MAPK is involved in the suppression of cell proliferation and mitochondrial activation-mediated cell death pathway; (5) in mice, oral supplementation with beta-glucan reduces pulmonary metastasis of 3LL cells and peritoneal disseminated metastasis of HRA cells and inhibits the growth of these metastatic tumors in lung or peritoneal cavity, in part, by suppressing uPA expression; and (6) in an in vivo experimental metastasis assay, however, the oral supplementation with beta-glucan after i.v. tumor cell inoculation did not reduce the number of lung tumor colonies.

CONCLUSION

Treatment with beta-glucan may be beneficial for cancer patients with or at risk for metastasis. The beta-glucan-dependent signaling pathways are critical for our understanding of anticancer events and development of cancer therapeutic agents.

Protein-bound polysaccharide K induced apoptosis of the human Burkitt lymphoma cell line, Namalwa

Protein-bound polysaccharide K (PSK), which is derived from mushrooms belonging to the Basidiomycetes genus, has been clinically used as a biological response modifier (BRM) for the treatment of epithelial cancer patients in Japan and other Asian countries. There are a large number of studies on the biological activities of PSK as regards the activation of immunocompetent cells and the potential cytotoxic effects on epithelial cancer cells. However, only a few studies have been conducted to see the direct cytotoxic effects of PSK on hematological malignant cells. In this study, we investigated whether or not PSK was able to induce cellular apoptosis in hematological malignant cells. PSK was found to inhibit cell growth, and induced subsequent cellular apoptosis in the Burkkit lymphoma cell line (Namalwa), out of 33 hematological malignant cell lines tested. This PSK-induced apoptosis was neutralized by the addition of galactose to the culture medium, whereas apoptosis was augmented by treatment with beta-galactosidase, indicating the inhibitory involvement of galactose in the mechanism of action. These results provide initial evidence of the direct cytotoxic activity of PSK in a hematological malignant cell line, thus encouraging further molecular-level study of PSK-mediated apoptosis in malignant hematological cells.

Complementary and alternative therapies for cancer

Many cancer patients use therapies promoted as literal alternatives to conventional medical care. Such "alternative" modalities are unproven or were studied and found worthless. These can be harmful. An even greater proportion of cancer patients uses "complementary" therapies along with mainstream cancer treatment. Most are helpful adjunctive approaches that control symptoms and enhance quality of life. This review describes alternative as well as complementary therapies commonly used today by cancer patients. Herbal remedies also are discussed. Evidence regarding the efficacy and safety of complementary/alternative medicine (CAM) is reviewed, and implications for oncologists are discussed. To encourage open communication of CAM use by patients, oncologists should be knowledgeable about the most popular remedies and know where to find reliable information for themselves and for their patients.

Adjuvant immunochemotherapy with oral Tegafur/Uracil plus PSK in patients with stage II or III colorectal cancer: a randomised controlled study

Intravenous fluorouracil and leucovorin is the standard adjuvant treatment for stage III colon cancer. However, oral adjuvant chemotherapy is attractive because it has low toxicity and greater convenience. We investigated the benefits of oral protein-bound polysaccharide K (PSK) with tegafur/uracil (UFT) as an adjuvant in stage II and III colorectal cancer. Patients were assigned to groups that received either 3 g PSK plus 300 mg UFT, or 300 mg UFT alone orally each day for a 2-year period following intravenous mitomycin C. Of 207 registered patients, 205 with stage II (n=123) or III (n=82) were analysed. The 5-year disease-free survival was 73.0% (95% CI 65.6-80.4%) with PSK (n=137) and 58.8% (95% CI 47.1-70.5%) in the controls (n=68) (P=0.016). Polysaccharide K reduced the recurrence by 43.6% (95% CI 4.5-66.7%) and mortality by 40.2% (95% CI -12.5 to 68.3%). The 5-year survival was 81.8% (95% CI 75.3-88.2%) in the PSK group and 72.1% (95% CI 61.4-82.7%) in the control group (P=0.056). In stage III patients, disease-free and overall survivals in patients receiving PSK were increased significantly: 60.0% (95% CI 47.1-72.9%) and 74.6% (95% CI 63.0-86.1%) in the PSK group as compared with 32.1% (95% CI 14.8-49.4%) and 46.4% (95% CI 28.0-64.9%) in the controls (P=0.002 and 0.003, respectively). Polysaccharide K prevented recurrence, particularly lung metastases (P=0.02; odds ratio 0.27; 95% CI 0.09-0.77). In the models, the presence of regional metastases (relative risk, 2.973; 95% CI 1.712-5.165; P<0.001), omission of PSK (relative risk, 2.106; 95% CI 1.221-3.633; P=0.007), and higher primary tumour (relative risk, 4.398; 95% CI 1.017-19.014; P=0.047) were each significant indicators of recurrence. Adverse effects were mild and compliance was good. Oral PSK with UFT reduced recurrence in stage II and III colorectal cancer, and increased survival in stage III.

Coriolus versicolor polysaccharide peptide slows progression of advanced non-small cell lung cancer

BACKGROUND

Non-small cell lung cancer (NSCLC) is a leading cause of cancer deaths, and over 60% of patients present with advanced stages. Although polysaccharide peptides (PSP), isolated from the fungus Coriolus versicolor, have been reported to have anti-tumor effects, its clinical efficacy has not been properly evaluated.

METHODS

Double-blind placebo-controlled randomized study to evaluate the effects of 28-day administration of PSP (Windsor Pharmaceutical, Hong Kong) on patients, who had completed conventional treatment for advanced NSCLC.

RESULTS

Thirty-four patients, with no significant difference in their baseline demographic, clinical or tumor characteristics, or previous treatment regimes (P>0.05) were recruited into each of the PSP and control arms. After 28-day treatment, there was a significant improvement in blood leukocyte and neutrophil counts, serum IgG and IgM, and percent of body fat among the PSP, but not the control, patients (P<0.05). Although the evaluable PSP patients did not improve in NSCLC-related symptoms, there were significantly less PSP patients withdrawn due to disease progression, than their control counterparts (5.9 and 23.5%, respectively; P=0.04; OR 4.00). There was no reported adverse reaction attributable to the trial medications.

CONCLUSION

PSP treatment appears to be associated with slower deterioration in patients with advanced NSCLC.

Botanical medicines for the treatment of cancer: rationale, overview of current data, and methodological considerations for phase I and II trials

There appears to be exceptional and growing public enthusiasm for botanical, or "herbal", medicines, especially amongst cancer patients. This has recently begun to be matched by increasing scientific attention. Whilst it is known that plant extracts are active against cancer, the standard approach has been to isolate, synthesize and administer the single chemical compound thought responsible for this effect. However, different components in a botanical may have synergistic activities. There is also some evidence that the presence of multiple compounds in a botanical extract can buffer the toxic effects of a single constituent. Though many of the botanicals popular among patients are probably not of benefit (e.g. Mistletoe, Pau D'arco), several botanicals have shown promise in Phase III (Sho-saiko-to, PSK) or Phase II (PC-SPES) trial. Quality control of botanicals poses significant challenges: small differences in genetics, soil, temperature, moisture and time of harvesting can lead to significant differences in the concentration of important constituents. Phase I and II methodology is also problematic: botanicals have low toxicity and are unlikely to cause rapid tumor regression. There is currently minimal regulation of botanical medicines.

Bioactive polysaccharides from traditional Chinese medicine herbs as anticancer adjuvants

PURPOSE OF STUDY

To review the nature, extent, bioactivities, and clinical application of polysaccharides in Traditional Chinese Medicine (TCM) especially as adjuvants in cancer treatment.

METHODOLOGY

Literature review.

FINDINGS

Many fungal- and plant-derived bioactive polysaccharides with a broad range of immunomodulatory activities are found in TCM. Some such polysaccharides have been developed into drugs and show clinical efficacy in controlled trials while the majority of such compounds remain as nutraceuticals with only preliminary research. Such polysaccharides are generally nontoxic and possess other bioactivities such as inducing differentiation, stimulating hematopoiesis, antimetastasis, and antiangiogenesis, which make them ideal adjuvants in modern cancer therapy.

CONCLUSION

Bioactive polysaccharides occur extensively in TCM herbs and are the basis of potentially useful application of TCM as an adjuvant in cancer therapies.

Immunomodulatory effects of low dose cis-Diaminedichloroplatinum (cisplatin) combined with UFT and PSK in patients with advanced colorectal cancer

It is well known that cell-mediated immunity is suppressed in patients with neoplastic diseases. We have reported that soluble receptors for interleukin-2 (sIL-2R) and tumor necrosis factor (sTNF-R1) are elevated in the serum of patients with advanced colorectal cancer. The presence of these soluble receptors and immunosuppressive cytokines, including interleukin-10 (IL-10), might be important in the mechanisms of immunosuppression. cis-Diaminedichloroplatinum (cisplatin) has been reported to immunomodulate, especially when used in low dose in combination with 5-Fluorouracil (5-FU). In this study, cisplatin and UFT, a form of uracil and tegafur which is a prodrug of 5-FU, were administered with immunomodulator Polysaccharide K (PSK) to ten patients with colorectal cancer, who showed distant metastasis in the liver or lung, and the serum levels of sIL-2R and sTNF-R1 and the production of gamma-interferon (gamma-INF) and interleukin-10 by peripheral blood mononuclear cells were measured. The serum concentrations of sIL-2R and the production of IL-10 were reduced (p < 0.05) after 2 months of treatment. Thus, this combination appeared to have immunomodulative potential in patients with advanced colorectal cancer.

Protective effects of a protein-bound polysaccharide, PSK, on Candida albicans infection in mice via tumor necrosis factor-alpha induction

We investigated the protective mechanism of a protein-bound polysaccharide, PSK, against lethal infection with Candida albicans (C. albicans) in mice. (1) In BALB/c mice inoculated intravenously with C. albicans, the intraperitoneal (ip) administration of PSK increased survival rates and prolonged the survival period depending on the time of administration, the dosage, and the size of fungal inoculum; the maximal effect was obtained when PSK 250 mg/kg was ip administered to mice 24 h before inoculation of 1 x 10(6) C. albicans (30 days survivors showed 60% and the mean survival period of mice with fatal infection increased 209%). (2) The protective effect of PSK was significantly decreased in mice treated with cyclophosphamide or carrageenan, or in mice treated previously with anti-tumor necrosis factor-alpha (TNF-alpha) antibody. (3) The administration of PSK significantly enhanced the expression of TNF-alpha gene in spleen and increased leukocyte functions from 6 h to 1 day after inoculation. (4) When the PSK fraction subjected to hydrolysis with beta1-3 glucanase or hydrazine was used instead of PSK, the anti-fungal activities were significantly decreased. These findings suggested that the protective effect of PSK on lethal C. albicans infection in mice was mainly produced via TNF-alpha functions, and that beta 1-3 glucan and protein moiety in PSK molecule were involved in the expression of the activities.