A study on the immunomodulation of polysaccharopeptide through the TLR4-TIRAP/MAL-MyD88 signaling pathway in PBMCs from breast cancer patients

MyD88 signaling pathways: role in breast cancer

MyD88 plays a central role in breast cancer, exerting a multitude of effects that carry substantial implications. Elevated MyD88 expression is closely associated with aggressive tumor characteristics, suggesting its potential as a valuable prognostic marker and therapeutic target. MyD88 exerts influence over several critical aspects of breast cancer, including metastasis, recurrence, drug resistance, and the regulation of cancer stem cell properties. Furthermore, MyD88 modulates the release of inflammatory and chemotactic factors, thereby shaping the tumor's immune microenvironment. Its role in immune response modulation underscores its potential in influencing the dynamic interplay between tumors and the immune system. MyD88 primarily exerts intricate effects on tumor progression through pathways such as Phosphoinositide 3-kinases/Protein kinase B (PI3K/Akt), Toll-like Receptor/Nuclear Factor Kappa B (TLR/NF-κB), and others. Nevertheless, in-depth research is essential to unveil the precise mechanisms underlying the diverse roles of MyD88 in breast cancer. The translation of these findings into clinical applications holds great promise for advancing precision medicine approaches for breast cancer patients, ultimately enhancing prognosis and enabling the development of more effective therapeutic strategies.

COVID-19 and Cancer Diseases-The Potential of Coriolus versicolor Mushroom to Combat Global Health Challenges

Coriolus versicolor (CV) is a common species from the Polyporaceae family that has been used in traditional Chinese herbal medicine for over 2000 years. Among well-described and most active compounds identified in CV are polysaccharopeptides, such as polysaccharide peptide (PSP) and Polysaccharide-K (PSK, krestin), which, in some countries, are already used as an adjuvant agent in cancer therapy. In this paper, research advances in the field of anti-cancer and anti-viral action of CV are analyzed. The results of data obtained in in vitro and in vivo studies using animal models as well as in clinical research trials have been discussed. The present update provides a brief overview regarding the immunomodulatory effects of CV. A particular focus has been given to the mechanisms of direct effects of CV on cancer cells and angiogenesis. A potential use of CV compounds in anti-viral treatment, including therapy against COVID-19 disease, has also been analyzed based on the most recent literature. Additionally, the significance of fever in viral infection and cancer has been debated, providing evidence that CV affects this phenomenon.

Polysaccharide-Peptide from Trametes versicolor: The Potential Medicine for Colorectal Cancer Treatment

The incidence and mortality of colorectal cancer have shown an upward trend in the past decade. Therefore, the prevention, diagnosis, and treatment of colorectal cancer still need our continuous attention. Finding compounds with strong anticancer activity and low toxicity is a good strategy for colorectal cancer (CRC) therapy. Trametes versicolor is a traditional Chinese medicinal mushroom with a long history of being used to regulate immunity and prevent cancer. Its extractions were demonstrated with strong cell growth inhibitory activity on human colorectal tumor cells, while the anticancer activity of them is not acted through a direct cytotoxic effect. However, the intricacy and high molecular weight make mechanistic research difficult, which restricts their further application as a medication in clinical cancer treatment. Recent research has discovered a small molecule polysaccharide peptide derived from Trametes versicolor that has a distinct structure after decades of Trametes versicolor investigation. Uncertain molecular weight and a complex composition are problems that have been solved through studies on its structure, and it was demonstrated to have strong anti-proliferation activity on colorectal cancer in vitro and in vivo via interaction with EGFR signaling pathway. It opens up new horizons for research in this field, and these low molecular weight polysaccharide peptides provide a new insight of regulation of colorectal cancer proliferation and have great potential as drugs in the treatment of colorectal cancer.

Trametes versicolor (Synn. Coriolus versicolor) Polysaccharides in Cancer Therapy: Targets and Efficacy

Coriolus versicolor (L.) Quél. is a higher fungi or mushroom which is now known by its accepted scientific name as Trametes versicolor (L.) Lloyd (family Polyporaceae). The polysaccharides, primarily two commercial products from China and Japan as PSP and PSK, respectively, have been claimed to serve as adjuvant therapy for cancer. In this paper, research advances in this field, including direct cytotoxicity in cancer cells and immunostimulatory effects, are scrutinised at three levels: in vitro, in vivo and clinical outcomes. The level of activity in the various cancers, key targets (both in cancer and immune cells) and pharmacological efficacies are discussed.

Astragalus polysaccharides (PG2) Enhances the M1 Polarization of Macrophages, Functional Maturation of Dendritic Cells, and T Cell-Mediated Anticancer Immune Responses in Patients with Lung Cancer

Background: Recently, we demonstrated that Astragalus polysaccharide (PG2), the active ingredient in dried roots of astragalus membranaceus, ameliorates cancer symptom clusters and improves quality of life (QoL) in patients with metastatic disease by modulating inflammatory cascade against the background roles of inflammatory cells, including macrophages, dendritic cells (DCs), and cytotoxic T lymphocytes (CTLs) in tumor initiation, metastasis, and progression. Nevertheless, the role of PG2 in the modulation of anticancer immunogenicity and therapeutic response remains relatively underexplored and unclear. Purpose: The present study investigates how and to what extent PG2 modulates cellular and biochemical components of the inflammatory cascade and enhances anticancer immunity, as well as the therapeutic implication of these bio-events in patients with lung cancer. Methods and Results: Herein, we demonstrated that PG2 significantly increased the M1/M2 macrophage polarization ratio in non-small cell carcinoma (NSCLC) H441 and H1299 cells. This PG2-induced preferential pharmacologic up-regulation of tumoral M1 population in vitro positively correlated with the downregulation of tumor-promoting IL-6 and IL-10 expression in NSCLC cell-conditioned medium, with concomitant marked inhibition of cell proliferation, clonogenicity, and tumorsphere formation. Our ex vivo results, using clinical sample from our NSCLC cohort, demonstrated that PG2 also promoted the functional maturation of DCs with consequent enhancement of T cell-mediated anticancer immune responses. Consistent with the in vitro and ex vivo results, our in vivo studies showed that treatment with PG2 elicited significant time-dependent depletion of the tumor-associated M2 population, synergistically enhanced the anti-M2-based anticancer effect of cisplatin, and inhibited xenograft tumor growth in the NSCLC mice models. Moreover, in the presence of PG2, cisplatin-associated dyscrasia and weight-loss was markedly suppressed. Conclusion: These results do indicate a therapeutically-relevant role for PG2 in modulating the M1/M2 macrophage pool, facilitating DC maturation and synergistically enhancing the anticancer effect of conventional chemotherapeutic agent, cisplatin, thus laying the foundation for further exploration of the curative relevance of PG2 as surrogate immunotherapy and/or clinical feasibility of its use for maintenance therapy in patients with lung cancer.

Astragalus polysaccharide (PG2) Ameliorates Cancer Symptom Clusters, as well as Improves Quality of Life in Patients with Metastatic Disease, through Modulation of the Inflammatory Cascade

Background: Improving patients' quality of life (QoL) is a principal objective of all treatment in any clinical setting, including oncology practices. Cancer-associated inflammation is implicated in disease progression and worsening of patients' QoL. Conventional anticancer therapeutics while selectively eliminating cancerous cells, are evaded by stem cell-like cells, and associated with varying degrees of adverse effects, thus reducing patients' QoL. This necessitates novel therapeutic approaches with enhanced efficacy, minimal or no treatment-related adverse effects, and improved QoL in patients with cancer, especially those with metastatic/advance stage disease. Methods: Sequel to our team's previous publication, the present study explores probable effects of Astragalus polysaccharides (PG2) on cancer-related inflammatory landscape and known determinants of QoL, as well as the probable link between the two to provide mechanistic insight. In an exploratory double blind randomized controlled trial using patients with metastatic disease (n = 23), we comparatively evaluated the therapeutic efficacy of high (500 mg) or low (250 mg) dose PG2 administered intravenously (i.v.), with particular focus on its suggested anti-inflammatory function and the probable effect of same on QoL indices at baseline, then at weeks 4 and 8 post-PG2 treatment. Results: All 23 patients with metastatic disease treated with either low or high PG2 experienced reduced pain, nausea, vomiting, and fatigue, as well as better appetite and sleep, culminating in improved global QoL. This was most apparent in the high dose group, with significant co-suppression of pro-inflammatory interleukin (IL)-1β, IL-4, IL-6, IL-13, IL-17, monocytes chemotactic protein (MCP)1, granulocyte-macrophage colony-stimulating factor (GM-CSF), vascular endothelial growth factor (VEGF), tumor growth factor (TGF)-β1, interferon (IFN)-γ, and immune suppressors IL-10 and IL-12. Univariate and multivariate analyses revealed that IL-1β, IL-13 and GM-CSF are independent prognosticators of improved QoL. Conclusion: This proof-of-concept study provides premier evidence of functional association between PG2 anti-inflammatory effects and improved QoL in patients with advanced stage cancers, laying the groundwork for future larger cohort blinded controlled trials to establish the efficacy of PG2 as adjuvant anticancer therapy in metastatic or advanced stage clinical settings.

Extract from Coriolus versicolor fungus partially prevents endotoxin tolerance development by maintaining febrile response and increasing IL-6 generation

Endotoxin tolerance is defined as a reduced endotoxin-induced fever following repeated injections of lipopolysaccharide (LPS). Clinical examples of endotoxin tolerance include sepsis or cystic fibrosis. This state is characterized by inhibition of pro-inflammatory cytokines production and decrease in nuclear factor-kappa B (NF-κB) activation. Extract from Coriolus versicolor (CV) fungus is classified as a biological response modifier, which exhibits various biological activities, including immunopotentiating properties. The aim of study was to examine the effect of CV extract injection on body core temperature of Wistar rats during LPS-induced endotoxin tolerance. Body temperature was measured using biotelemetry. CV extract was injected intraperitoneally (100 mg kg^-1) 2 h prior to the first LPS peritoneal administration (50 μg/kg). Endotoxin tolerance was induced by three consecutive daily injections of LPS at the same dose. We also investigated the influence of CV extract pre-injection on the properties of peripheral blood mononuclear cells (PBMCs) isolated from LPS-treated rats in response to LPS stimulation ex vivo. PBMCs were isolated 2 h after the first LPS injection. After 24 h pre-incubation, the cells were stimulated with LPS (1 μg ml^-1) for 4 h. Our results revealed that CV extract partially prevents endotoxin tolerance through maintaining febrile response in rats following consecutive exposure to LPS. This state was accompanied by the ability of PBMCs isolated from rats injected with CV extract and LPS to release larger amounts of interleukin 6 and greater NF-κB activation in response to LPS stimulation ex vivo compared with the cells derived from rats injected only with LPS. Data also showed that CV extract augmented mitogenic effect of LPS on PBMCs and caused increase in reactive oxygen species generation. We concluded that CV extract, by a modifying effect on body temperature during endotoxin tolerance, can be consider as the immunostimulating agent, which prevents the non-specific refractoriness described in patients with sepsis or ischemia.

TLR4/MyD88 signaling determines the metastatic potential of breast cancer cells

The influence of Toll-like receptor (TLR)4/myeloid differentiation factor (MyD)88 signaling on the invasion and metastasis of cancer cells has been previously reported. The purpose of the present study was to determine the role of TLR4/MyD88 in breast cancer cell migration and invasion, and to discover novel therapeutic targets for breast cancer treatment. TLR4, MyD88 and high mobility group box 1 (HMGB1) mRNA expression levels were assessed in highly invasive human MDA-MB-231 breast cancer cells, breast cancer cells with a low rate of invasion (MCF-7) and normal human MDA-Kb2 mammary gland cells by reverse transcription-quantitative polymerase chain reaction. The protein expression levels of these markers were detected by western blotting and immunofluorescence. Randomly selected breast cancer and paracarcinoma tissues were used to measure TLR4 and MyD88 protein expression levels by immunohistochemistry. The mRNA and protein expression levels of TLR4 and MyD88 were significantly higher in MDA-MB-231 cells compared with either MCF-7 cells or MDA-Kb2 cells. The mRNA and protein expression levels of HMGB1 were comparable in the two breast cancer cell lines, with no statistical difference (P>0.05). TLR4 and MyD88 protein expression levels were also significantly higher in breast cancer tissues compared with paracarcinoma tissues (P<0.05). TLR4 and MyD88 protein expression levels were positively correlated with axillary lymph node metastasis and histological grade (P<0.05). TLR4/MyD88 expression levels were positively correlated with the metastasis of breast cancer cells. TLR4/MyD88 may be useful as a novel biomarker to evaluate the prognosis and treatment of patients with breast cancer.

Naturally Derived Anti-HIV Polysaccharide Peptide (PSP) Triggers a Toll-Like Receptor 4-Dependent Antiviral Immune Response

Aim

Intense interest remains in the identification of compounds to reduce human immunodeficiency virus type 1 (HIV-1) replication. Coriolus versicolor's polysaccharide peptide (PSP) has been demonstrated to possess immunomodulatory properties with the ability to activate an innate immune response through Toll-like receptor 4 (TLR4) showing insignificant toxicity. This study sought to determine the potential use of PSP as an anti-HIV agent and whether its antiviral immune response was TLR4 dependent.

Materials and Methods

HIV-1 p24 and anti-HIV chemokine release was assessed in HIV-positive (HIV+) THP1 cells and validated in HIV+ peripheral blood mononuclear cells (PBMCs), to determine PSP antiviral activity. The involvement of TLR4 activation in PSP anti-HIV activity was evaluated by inhibition.

Results

PSP showed a promising potential as an anti-HIV agent, by downregulating viral replication and promoting the upregulation of specific antiviral chemokines (RANTES, MIP-1α/β, and SDF-1α) known to block HIV-1 coreceptors in THP1 cells and human PBMCs. PSP produced a 61% viral inhibition after PSP treatment in HIV-1-infected THP1 cells. Additionally, PSP upregulated the expression of TLR4 and TLR4 inhibition led to countereffects in chemokine expression and HIV-1 replication.

Conclusion

Taken together, these findings put forward the first evidence that PSP exerts an anti-HIV activity mediated by TLR4 and key antiviral chemokines. Elucidating these new molecular mediators may reveal additional drug targets and open novel therapeutic avenues for HIV-1 infection.

Medicinal mushrooms as an attractive new source of natural compounds for future cancer therapy

Medicinal mushrooms have been used throughout the history of mankind for treatment of various diseases including cancer. Nowadays they have been intensively studied in order to reveal the chemical nature and mechanisms of action of their biomedical capacity. Targeted treatment of cancer, non-harmful for healthy tissues, has become a desired goal in recent decades and compounds of fungal origin provide a vast reservoir of potential innovational drugs. Here, on example of four mushrooms common for use in Asian and Far Eastern folk medicine we demonstrate the complex and multilevel nature of their anticancer potential, basing upon different groups of compounds that can simultaneously target diverse biological processes relevant for cancer treatment, focusing on targeted approaches specific to malignant tissues. We show that some aspects of fungotherapy of tumors are studied relatively well, while others are still waiting to be fully unraveled. We also pay attention to the cancer types that are especially susceptible to the fungal treatments.

Hepatoprotective Effects of a Functional Formula of Three Chinese Medicinal Herbs: Experimental Evidence and Network Pharmacology-Based Identification of Mechanism of Action and Potential Bioactive Components

Various Chinese herbal medicines (CHMs) have shown beneficial liver protection effects. Jian-Gan-Bao (JGB), a functional herbal formula, consists of three famous CHMs, including Coriolus versicolor, Salvia miltiorrhiza and Schisandra chinensis, which has been used as a folk medicine for several chronic liver diseases. In the present study, we aim systemically to evaluate the effects of JGB on acute and chronic alcoholic liver diseases (ALD) as well as non-alcoholic fatty liver disease (NAFLD) in mouse models, and identify its potential bioactive components and mechanism of action. JGB showed preventive effects for acute and chronic ALD as well as NAFLD, while post-treatment of JGB showed no significant effect, suggesting the nature of JGB as a health supplement rather than a drug. Furthermore, a compound-target network was constructed to identify the potential bioactive compounds and pathways that regulate its hepatoprotective effects. There are 40 bioactive compounds and 15 related targets that have been identified via this network pharmacology study. Among them are miltirone, neocryptotanshinone II and deoxyshikonin, with desirable pharmaceutical properties. Pathways relating to inflammation, fatty acid oxidation, tumor necrosis factor (TNF) production and cell proliferation were predicted as bioactive compounds and potential underlying mechanisms, which should be the focus of study in this field in the future.

A novel synthetic ursolic acid derivative inhibits growth and induces apoptosis in breast cancer cell lines

The present study investigated the anticancer functions of ursolic acid (UA) and its novel derivatives, with a nitrogen-containing heterocyclic scaffold and the privileged fragment at the C-28 position on apoptosis induction, cell proliferation and cell cycle in human BC lines. UA was chemically modified in the present study to increase its antitumor activity and bioavailability. A novel UA derivative, FZU3010, was synthesized using a nitrogen-containing heterocyclic scaffold and a privileged fragment at the C-28 position. Sulforhodimine B assays were used to measure the effect of UA and different concentrations of FZU3010 on the viability of breast cancer (BC) SUM149PT and HCC1937 cells. FZU3010 significantly repressed the proliferation of the two cancer cell lines in a dose-dependent manner, with a half-maximal inhibitory concentration of 4-6 µM, and exhibited decreased cytotoxicity compared with vehicle-treated cell lines. The effect of FZU3010 on cell cycle distribution and cellular apoptosis was also investigated. The results of this investigation indicated that FZU3010 significantly increased the number of SUM149PT and breast cancer HCC1937 cells in the G₀/G₁ phase in a dose-dependent manner. Additionally, at a concentration of 5 µM, the capability of FZU3010 to induce BC apoptosis was significantly higher than the capability of UA. Thus, the results of the current study indicated that FZU3010 induced apoptosis in BC cells, together with induction of cell cycle arrest at the S and G₀/G₁ phase. FZU3010 may therefore be considered as a potential therapeutic agent for the treatment of BC.

Immunomodulatory Properties of Coriolus versicolor: The Role of Polysaccharopeptide

Traditional uses of herbal medicine have depended mostly on anecdotal evidence for much of history. The increasing application of scientific rigor to the study some of these traditional therapies in recent years has revealed potent bioactivity, notably demonstrated by the 2015 Nobel Prize for the discovery of an antimalarial compound from traditional Chinese herbs. Given the recent successes of immunotherapy and checkpoint blockade, there is a renewed interest in identifying new drugs with immunomodulatory effects. As an estimated 45-60% of cancer patients worldwide are reported to use complementary alternative medicine alongside traditional therapy, this review will highlight the literature on the immunomodulatory effects of one of these compounds. We report on the induction of a largely pro-inflammatory cytokine profile by the polysaccharopeptide (PSP) isolated from the Coriolus versicolor (Yun zhi) mushroom, as well as its effects on various immune subsets, and the clinical data that have led to its widespread adoption as an adjunct cancer therapeutic in many Eastern cultures. Particular focus is given to the potential mechanisms underlying the bioactivity of PSP and reports of its ability to promote antitumor immunity by helping overcome tolerogenic tumor microenvironments.

Fever-range hyperthermia inhibits cells immune response to protein-bound polysaccharides derived from Coriolus versicolor extract

The aim of the study was to explore whether fever-range hyperthermia (FRH) might enhance the anticancer and immunoregulatory activities of protein-bound polysaccharides (PBP), a class of fungus derived immunomodifiers used in the cancer adjuvant therapy. Blood lymphocytes and breast cancer cells (MCF-7) were cultured at 39.5°C in humidified atmosphere containing 5% CO₂ for 2h. After rested at 37°C for 6h, the cells were treated with PBP extract at 100- and 300μg/ml concentration. After indicated time, the proliferative response was analyzed and cytokine mRNA expression assessment was performed by qRT-PCR. In animal model, the FRH was induced by placing rats in the Homeothermic Controller with heating blanket. Animals were heated until Tb reached 39.5°C (±0.2°C) and were maintained at this temperature for 30min. The protein-bound polysaccharides solution was injected i.p. at a dose of 100 mg/kg 6h post FRH. Twenty four hours after treatment, the blood was collected and cytokines expression analysis were performed. The results have shown that fever-range hyperthermia has an inhibitory effect on PBP extract-induced proliferative response of blood lymphocytes, as well as IL-1β and IL-6 mRNA expression. Moreover, the temperature of 39.5°C blocks PBP-induced cytotoxicity against MCF-7 cells, which correlates with significant reduction in TNF-α level. Combined treatment of rats (FRH+PBP) results in decrease of IL-1β, IL-6 and TNF-α mRNA expression in peripheral blood mononuclear cells compared to cells derived from rats treated with protein-bound polysaccharides extract alone. This study demonstrates that fever-range temperature inhibits immunostimulatory as well as anticancer effects mediated by protein-bound polysaccharides.

Immunomodulatory effect of APS and PSP is mediated by Ca2+-cAMP and TLR4/NF-κB signaling pathway in macrophage

OBJECTIVE

This study is to investigate the role of second messengers and TLR4/NF-κB signaling pathway in the immunomodulatory activities of Astragalus polysaccharide (APS) and Polysaccharopeptide (PSP) in macrophages.

METHODS

RAW 264.7 macrophage cells were treated with APS, PSP, lipopolysaccharide (LPS), or NiCl₂. Power-spectral method was used to detect protein kinase C (PKC) and Griess reaction to detect nitric oxide (NO). ELISA was conducted to detect cyclic adenosine monophosphate (cAMP), diglycerides (DAG), inositol 1, 4, 5-triphosphate (IP3), tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6). Confocal laser scanning microscopy was performed to detect calcium level. qRT-PCR and Western blot was used to detect mRNA and protein expression of NF-κB.

RESULTS

APS and PSP significantly increased the concentrations of intracellular second messengers (NO, cAMP, DAG, IP3, Ca²⁺) and the activity of PKC in macrophages (p<0.05).The intracellular NF-κB mRNA and protein levels were significantly increased in macrophages treated by APS and PSP (p<0.05), whereas those were significantly decreased after NiCl₂ incubation (p<0.05). Similarly, the secretion of TNF-α and IL-6 were significantly decreased by the treatment of NiCl₂.

CONCLUSION

Our findings strongly suggest that Ca²⁺-cAMP and TLR4/NF-κB signaling pathways are, at least partly, involved in APS and PSP mediated immunomodulatory activities in macrophages.

Protein-bound polysaccharides from Coriolus versicolor attenuate LPS-induced synthesis of pro-inflammatory cytokines and stimulate PBMCs proliferation

Protein-bound polysaccharides (PBP) isolated from Coriolus versicolor (CV) are classified as biological response modifiers capable of exhibiting various biological activities, such as anti-tumour and immunopotentiating activity. Since we have found in vivo studies that the tested PBP induced prolongation of endotoxin fever in rats, the aim of the present study was to investigate the in vitro effect of the PBP on the production of pro-inflammatory cytokines by the lipolysaccharide (LPS)-stimulated rat peripheral blood mononuclear cells (PBMCs). The results showed that the PBP affect the immunomodulating properties of the LPS-treated PBMCs by the enhancement of mitogenic activity and attenuation of the LPS-induced production of interleukin (IL)-1β and IL-6. Moreover, the tested polysaccharides peptides themselves also exhibit immunomodulatory properties manifested in the increased cell proliferation and pro-inflammatory cytokine release from PBMCs. The effect of PBP on the both phenomena was time-dependent and occurred in the U-shaped dose response manner. These findings are significant when considering the use of commercially available PBP from CV extract by cancer patients suffering from immunodeficiency, who may experience microbial infections during therapy.

Toll-like receptor 4-related immunostimulatory polysaccharides: Primary structure, activity relationships, and possible interaction models

Toll-like receptor (TLR) 4 is an important polysaccharide receptor; however, the relationships between the structures and biological activities of TLR4 and polysaccharides remain unknown. Many recent findings have revealed the primary structure of TLR4/MD-2-related polysaccharides, and several three-dimensional structure models of polysaccharide-binding proteins have been reported; and these models provide insights into the mechanisms through which polysaccharides interact with TLR4. In this review, we first discuss the origins of polysaccharides related to TLR4, including polysaccharides from higher plants, fungi, bacteria, algae, and animals. We then briefly describe the glucosidic bond types of TLR4-related heteroglycans and homoglycans and describe the typical molecular weights of TLR4-related polysaccharides. The primary structures and activity relationships of polysaccharides with TLR4/MD-2 are also discussed. Finally, based on the existing interaction models of LPS with TLR4/MD-2 and linear polysaccharides with proteins, we provide insights into the possible interaction models of polysaccharide ligands with TLR4/MD-2. To our knowledge, this review is the first to summarize the primary structures and activity relationships of TLR4-related polysaccharides and the possible mechanisms of interaction for TLR4 and TLR4-related polysaccharides.

Polysaccharide peptides from Coriolus versicolor exert differential immunomodulatory effects on blood lymphocytes and breast cancer cell line MCF-7 in vitro

The protein-bound polysaccharides (PBP), isolated from Coriolus versicolor (CV) fungus, are considered as natural compounds with potential therapeutic applications. The immunopotentiating and antitumor activity of polysaccharopeptides has been previously examined, however similar findings could not be achieved. The source of PBP, variations in extraction process as well as environmental factors seems to affect the biological properties of these active CV components. Since further analysis are needed to draw more definite conclusion, the present study aimed to investigate the immunomodulatory properties of the PBP extract, isolated from commercially available capsules of C. versicolor. Our results revealed that the effect mediated by PBP extract depends on the target cells. We reported that the polysaccharopeptides induced a significant decrease in breast cancer MCF-7 cells growth, which was TNF-α-dependent phenomenon. Interestingly, the level of two others cytokines, IL-1β and IL-6 was not affected. On the other hand, in this study we noticed that protein-bound polysaccharides extracted from CV significantly augmented the proliferative response of blood lymphocytes in a time-dependent manner, which was associated with IL-6 and IL-1β mRNA upregulation. Moreover we found that the cells response to PBP stimuli might be inversely related to its concentration.

A study on immunomodulatory mechanism of Polysaccharopeptide mediated by TLR4 signaling pathway

Background

Polysaccharopeptide (PSP), isolated from Coriolus versicolor COV-1 strain, is a protein-bound polysaccharide widely used as immunoadjuvant for cancer immunotherapy. Although the immunomodulatory activity of PSP has been well established, the precise molecule mechanisms of its biological activity have yet to be fully elucidated.

Methods

In the present study, we first investigated the immunomodulatory activity of PSP in peritoneal macrophages from C57BL/10J (TLR4^+/+) and C57BL/10ScCr (TLR4^-/-) mice carrying a defective toll-like receptor-4 (TLR4) gene and then evaluated PSP for its effect on tumor inhibition rates and the immune organ index in above two different strains of mice. In addition, PSP were also evaluated for its activation of TLR4, TLR4-downstream molecules (TRAF6, NF-κB and AP-1) in spleens of tumor-bearing C57BL/10J (TLR4^+/+) and C57BL/10ScCr (TLR4^-/-) mice.

Results

The results showed that PSP had adjuvant activities in stimulating expressions of cytokines as well as TLR4, TRAF6, phosphorylation of NF-κB p65 transcription factors and phosphorylation of c-Jun (a component of the transcription factor AP-1) in peritoneal macrophages from C57BL/10J (TLR4^+/+) mice but not from C57BL/10ScCr (TLR4^-/-) mice. In vivo PSP as well as Adriamycin (ADM) decreased the mean weights of tumors compared with normal saline and PSP increased thymus index and spleen index relative to ADM in tumor-bearing C57BL/10J (TLR4^+/+) mice but not in C57BL/10ScCr (TLR4^-/-) mice.

Conclusions

We demonstrated that PSP activates peritoneal macrophages in vitro via TLR4 signaling pathway and PSP functions its immunoregulatory effect in vivo also via TLR4 signaling pathway. These data strongly suggest TLR4 signaling pathway is involved in PSP-mediated immunomodulatory activities.