Target directed identification of natural bioactive compounds from filamentous fungi.

Some of the most powerful natural antimicrobial compounds originate from filamentous fungi. However, due to the diversity of compounds from plant and fungal origin, separation, isolation, and identification of bioactive constituents can be a long and tedious process. This study explores the effectiveness of thin layer chromatography (TLC) in combination with bioautography in the separation and identification of bioactive compounds from several filamentous fungi. Ultra-performance liquid chromatography coupled to photodiode array detector (UPLC-DAD) was employed to quantitatively identify phenolic composition. The total phenolic content of the selected filamentous fungi ranged from 31.85 mg g-1 to 101.77 mg g-1. Additionally, liquid chromatography mass spectrometry (LC/MS) determined the most abundant fatty acids were linoleic, palmitic, oleic, and stearic acid. Submerged cultivation of Grifola frondosa, Monascus purpureus, Lentinula edodes, Trametes versicolor and Pleurotus ostreatus proved to be an effective method to produce natural antimicrobial compounds.

Metabolomic comparison between natural Huaier and artificial cultured Huaier.

Vanderbylia robiniophila (Murrill) B.K. (Huaier) is a kind of higher fungal fruiting body that is parasitic on the trunk of Sophora japonica and Robinia pseudoacacia L.. As a traditional Chinese medicine with a history of more than 1,600 years, Huaier has attracted wide attention for its excellent anticancer activity. A systematic study on the metabolome differences between natural Huaier and artificial cultured Huaier was conducted using liquid chromatography-mass spectrometry in this study. Principal component analysis and orthogonal projection on latent structure-discriminant analysis results showed that cultured Huaier evidently separated and individually separated from natural Huaier, indicating metabolome differences between natural and cultured Huaier. Hierarchical clustering analysis was further performed to cluster the differential metabolites and samples based on their metabolic similarity. The higher contents of amino acids, alkaloids and terpenoids in natural Huaier make it an excellent choice as a traditional Chinese medicine for anticancer or nutritional supplementation. The results of the Bel-7,402 and A549 cell cytotoxicity tests showed that the anticancer activity of natural Huaier was better than that of cultured Huaier. This may be due to the difference in chemical composition, which makes the anticancer activities of natural and cultured Huaier different.

Biochemical characterization and biological properties of mycelium extracts from Lepista sordida GMA-05 and Trametes hirsuta GMA-01: new mushroom strains isolated in Brazil.

The objective of this study was to evaluate the antioxidant activity, determine and quantify the phenolic compounds and other compounds, and evaluate the cellular cytotoxicity of mycelium extracts of two new Basidiomycete mushrooms strains isolated in Brazil and identified as Lepista sordida GMA-05 and Trametes hirsuta GMA-01. Higher amounts of proteins, free amino acids, total and reducing carbohydrates, and phenolic compounds as chlorogenic, ferulic, caffeic, and gallic acids were found in extracts of T. hirsuta and L. sordida. Protocatechuic acid was found only in aqueous extracts of L. sordida. The TLC of the extracts showed the predominance of glucose and smaller amounts of xylose. It was observed through UPLC-MS higher amounts of phenolic compounds. The aqueous extract from T. hirsuta had the most noteworthy results in the antioxidant assays, especially the ABTS test. The cytotoxic activity was evaluated using two different cell lineages and showed higher toxicity for L. sordida in macrophages J774-A1. However, in Vero cells, it was 12.6-fold less toxic when compared to T. hirsuta. Thus, both mushrooms show potential as functional foods or additives, presenting phenolic content, antioxidant activity, and low cytotoxic activity in the tested cells.

Purification and Characterization Laccase from Trametes versicolor (L.) Lloyd in Submerged Fermentation.

<b>Background and Objective:</b> Laccase is classified as an oxidoreductase enzyme that catalyzes oxidation reactions of phenolic groups by using oxygen as its electron acceptor. Laccase isolated from <i>Trametes versicolor</i> (L.) Lloyd has a wide range of applications in the industrial sector. The use of enzymes in the industrial sector requires pure enzyme conditions from impurities so that the enzyme can maximize its ability in converting the substrate. This study aims to obtain enzyme activity and the characteristic of purified laccase enzymes isolated from <i>Trametes versicolor</i> (L.) Lloyd. <b>Materials and Methods:</b> This study was conducted with an experimental method followed by descriptive analysis. The steps of this research consist of a qualitative assay of laccase enzyme, crude laccase extract desalting by Sephadex G-25, laccase purification by Sephadex G-100 and laccase optimum pH characterization. <b>Results:</b> The result of this study showed that purification of laccase from <i>Trametes versicolor </i>(L.) Lloyd with Sephadex G-25 increases laccase enzyme-specific activity which is 10.966 U mg¹ and reaches 2.93-fold purity. The highest laccase enzyme activity was achieved at pH 4 with a value of laccase activity 62.39 U L¹. <b>Conclusion:</b> Based on current results, purifying laccase from <i>Trametes versicolor </i>(L.) Lloyd with Sephadex G-25 was recommended which resulting higher enzyme specific activity.

Differential effects of Huaier aqueous extract on human CD4+T lymphocytes from patients with primary immune thrombocytopenia.

Huaier, a traditional Chinese medicine, is currently used to treat certain types of cancer in the clinic and is also regarded as an immune-modulating and immune-enhancing agent that regulates immune cells. Emerging evidence indicates that an imbalance of immune cells, such as CD4+ T helper (Th) lymphocytes, contributes to the progression of immune thrombocytopenia (ITP), but the effects of Huaier on the regulation of CD4+ T cells are not yet fully elucidated. In the present study, Jurkat cells and peripheral blood mononuclear cells (PBMCs) from patients with ITP and healthy volunteers were treated with Huaier aqueous extract (HR). The CCK-8 assay revealed that HR suppressed the proliferation of Jurkat cells in a dose-dependent manner, whereas 3 mg/mL could decrease cell viability by 50%. At the latter concentration, the activation of CD4+ T cells from patients with ITP was partially attenuated. In addition, HR could correct the unbalanced Th1/Th2 polarization and inhibit the secretion of pro-inflammatory factors interleukin (IL)-2, tumor necrosis factor-α, and interferon-γ. It also suppressed Treg and facilitated Th17 differentiation, but did not change the levels of IL-10 and transforming growth factor-ß. Thus, this study provides more information on how Huaier regulates cellular immunity and improves our understanding of the use of Huaier in ITP.

Huaier extract restrains pancreatic cancer by suppressing Wnt/ß-catenin pathway.

Pancreatic cancer is a lethal disease, and new treatments need to be explored. Huaier extract is a traditional Chinese medicine that has been found to exert antitumor properties in some cancers. However, the role of Huaier extract in pancreatic cancer has not been examined. In this study, we found that the proliferation, migration, invasion and EMT (epithelial-mesenchymal transition) of pancreatic cancer cells were suppressed by treatment with Huaier extract and that apoptosis increased. We also observed that expression of ß-catenin was inhibited by Huaier extract. Furthermore, an animal study showed that Huaier extract slowed tumor growth in pancreatic cancer. Our results reveal that Huaier extract suppresses pancreatic cancer by inhibiting Wnt/ß-catenin pathway both in vitro and in vivo.

Elucidation of the decolorization of Congo Red by Trametes versicolor laccase in presence of ABTS through cyclic voltammetry.

The azo dye Congo red is heavily used in textile industries and is actively present in the wastewater run-offs. Its structural complexity and physical characteristics make it resistant to the physicochemical treatments employed by the industry. Over time, application of the enzyme laccase has proved to be quite useful due to its ability to oxidize and eventually decolorize the dye. Moreover, the use of ABTS as the electron mediator also helps in enhancing the oxidizing capability of the enzyme with congo red. The present study involves establishing the role of the individual components i.e. laccase, ABTS and the dye, in the LMS electrochemically. Congo red doesn't have any form of electrochemical activity by itself, but the enzyme brings about a substantial change by increasing the rate of reduction. The effect of ABTS, though same, is concentration-dependent. For LMS, laccase helps in bringing about the rate of reduction much faster in the presence of the mediator, initiating the decolorization of the dye.

Synthesis and Structure-Activity Relationship Studies of Hydrazide-Hydrazones as Inhibitors of Laccase from Trametes versicolor.

A series of hydrazide-hydrazones 1-3, the imine derivatives of hydrazides and aldehydes bearing benzene rings, were screened as inhibitors of laccase from Trametes versicolor. Laccase is a copper-containing enzyme which inhibition might prevent or reduce the activity of the plant pathogens that produce it in various biochemical processes. The kinetic and molecular modeling studies were performed and for selected compounds, the docking results were discussed. Seven 4-hydroxybenzhydrazide (4-HBAH) derivatives exhibited micromolar activity Ki = 24-674 µM with the predicted and desirable competitive type of inhibition. The structure-activity relationship (SAR) analysis revealed that a slim salicylic aldehyde framework had a pivotal role in stabilization of the molecules near the substrate docking site. Furthermore, the presence of phenyl and bulky tert-butyl substituents in position 3 in salicylic aldehyde fragment favored strong interaction with the substrate-binding pocket in laccase. Both 3- and 4-HBAH derivatives containing larger 3-tert-butyl-5-methyl- or 3,5-di-tert-butyl-2-hydroxy-benzylidene unit, did not bind to the active site of laccase and, interestingly, acted as non-competitive (Ki = 32.0 µM) or uncompetitive (Ki = 17.9 µM) inhibitors, respectively. From the easily available laccase inhibitors only sodium azide, harmful to environment and non-specific, was over 6 times more active than the above compounds.

Enhancement of the anti-inflammatory properties of grape pomace treated by Trametes versicolor.

The application of solid-state fermentation for the production of value-added products from the agro- and food-industry residues has been recently investigated greatly. The white-rot basidiomycete Trametes versicolor is a widely used fungi for the degradation lignocellulosic material in solid-state conditions. Grape pomace constitutes the major by-product of Vitis vinifera L. and is a source of compounds with recognized health benefits. In this study, a process for treating grape pomace with Trametes versicolor for 15 days under solid-state conditions was developed, and the phenolic profile and anti-inflammatory potential of the grape pomace extracts before and after treatment was studied. The anti-inflammatory potential of the grape pomace extracts was studied via tests based on the inhibition of 5-lipoxygenase and hyaluronidase, two key enzymes in inflammatory processes. A total of 24 phenolic compounds were identified and quantified by HPLC methods. With the exception of anthocyanins, an increase in phenolic acids, flavan-3-ols and the flavonol rutin was observed after a treatment period of 1-4 days with T. versicolor. Moreover, the increase in the phenolic content was accompanied by an enhancement in the anti-inflammatory activity of the grape pomace extracts, which was confirmed by the strong correlation between them. This is the first study providing evidence of the benefits of the application of fungal-based solid-state fermentation as an environmentally friendly process for the enhancement of the phenolic composition and anti-inflammatory potential of grape pomace, increasing the possibility of profiting from the great waste produced by the grape-processing industry.

A first report on competitive inhibition of laccase enzyme by lignin degradation intermediates.

Laccases have been widely explored for their ligninolytic capability in bioethanol production and bioremediation of industrial effluents. However, low reaction rates have posed a major challenge to commercialization of such processes. This study reports the first evidence of laccase inhibition by two types of lignin degradation intermediates - fungal-solubilized lignin and alkali-treated lignin - thus offering a highly plausible explanation for low reaction rates due to buildup of inhibitors during the actual process. Reversed-phase high-performance liquid chromatography revealed the presence of similar polar compounds in both lignin samples. A detailed kinetic study on laccase, using 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) as the substrate, was used to calculate the Michaelis constant (Km) and maximum reaction rate (Vmax). With an increase in the concentration of lignin degradation intermediates, Vmax remained nearly constant, while Km increased from 1.3 to 4.0 times that of pure laccase, revealing that the inhibition was competitive in nature. The kinetic studies reported here and the insight gained into the nature of inhibition can help design process strategies to mitigate this effect and improve overall process efficiency. This work is applicable to processes that employ laccase for delignification of biomass, such as second-generation biofuels processes, as well as for industrial effluent treatment in paper and pulp industries.

The mycelium of the Trametes versicolor (Turkey tail) mushroom and its fermented substrate each show potent and complementary immune activating properties in vitro.

BACKGROUND: The medicinal mushroom Trametes versicolor (Tv, Turkey Tail) is often prepared for consumption as a powder from the fungal mycelium and the fermented substrate on which it grew. The goal for this study was to evaluate the immune-modulating properties of the mycelium versus the fermented substrate, to document whether an important part of the immune-activating effects resides in the metabolically fermented substrate. METHODS: Tv mycelium was cultured on rice flour. The mycelium and the fermented substrate were mechanically separated, dried, and milled. The initial substrate served as a control. Aqueous fractions were extracted and passed through 0.22-µm filters. The remaining solids were passed through homogenization spin columns without filtration. The aqueous and solid fractions of the initial substrate (IS), the fermented substrate (FS), and the Trametes versicolor mycelium (TvM) were tested for immune-activating and modulating activities on human peripheral blood mononuclear cell cultures, to examine expression of the CD69 activation marker on lymphocytes versus monocytes, and on the T, NKT, and NK lymphocyte subsets. Culture supernatants were tested for cytokines using Luminex arrays. RESULTS: Both aqueous and solid fractions of TvM triggered robust induction of CD69 on lymphocytes and monocytes, whereas FS only triggered minor induction of CD69, and IS had no activating effect. The aqueous extract of TvM had stronger activating effects than the solid fraction. In contrast, the solid fraction of IS triggered a reduction in CD69, below levels on untreated cells. Both aqueous and solid fractions of FS triggered large and dose-dependent increases in immune-activating pro-inflammatory cytokines (IL-2, IL-6), anti-inflammatory cytokines Interleukin-1 receptor antagonist (IL-1ra) and Interleukin-10 (IL-10), anti-viral cytokines interferon-gamma (IFN-γ) and Macrophage Inflammatory Protein-alpha (MIP-1α), as well as Granulocyte-Colony Stimulating Factor (G-CSF) and Interleukin-8 (IL-8). TvM triggered more modest cytokine increases. The aqueous extract of IS showed no effects, whereas the solid fraction showed modest effects on induction of cytokines and growth factors. CONCLUSION: The results demonstrated that the immune-activating bioactivity of a mycelial-based medicinal mushroom preparation is a combination of the mycelium itself (including insoluble beta-glucans, and also water-soluble components), and the highly bioactive, metabolically fermented substrate, not present in the initial substrate.

Trametes orientalis polysaccharide alleviates PM2.5-induced lung injury in mice through its antioxidant and anti-inflammatory activities.

This paper examined the molecular conformation of Trametes orientalis polysaccharide (TOP-2) and evaluated the ameliorative effects of TOP-2 on PM2.5-induced lung injury in mice. The Congo red test and transmission electron microscopy (TEM) showed that TOP-2 had a triple-helical structure. PM2.5-induced pulmonary edema was ameliorated by TOP-2 intervention. PM2.5 notably increased the number of inflammatory cells and percentages of neutrophils in bronchoalveolar lavage fluid (BALF), and notably reduced the percentages of macrophages in BALF, while TOP-2 abolished these effects. The increased levels of total protein, albumin, C-reactive protein (CRP), myeloperoxidase (MPO), lactate dehydrogenase (LDH), alkaline phosphatase (AKP), acid sphingomyelinase (ASM), TNF-α, IL-1ß and IL-6 in BALF after PM2.5 exposure were inhibited by TOP-2. In addition, TOP-2 could not only remarkably promote the activities of antioxidant enzymes, but also reduce the levels of malondialdehyde (MDA), protein carbonyl group (PCG) and 8-hydroxy-2'-deoxyguanosine (8-OHdG). Furthermore, TOP-2 up-regulated the expressions of nuclear factor-erythroid 2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1) and inhibited the activation of NLR family pyrin domain-containing 3 (NLRP3) inflammasome in the lung tissue. These results hint that TOP-2 could alleviate PM2.5-induced lung injury in mice via its antioxidant and anti-inflammatory activities, and the underlying mechanisms, at least partly, depended on activation of the Nrf2/HO-1 pathway and inhibition of NLRP3 inflammasome.

A polysaccharide from Huaier ameliorates cisplatin nephrotoxicity by decreasing oxidative stress and apoptosis via PI3K/AKT signaling.

Cisplatin (CP), a common chemotherapy drug used in treatment of malignant tumors. Due to various side effects such as nephrotoxicity (kidney damage), it's efficiency and therapeutic application are limited. This study focuses on finding a suitable drug that would attenuate the side effects like kidney damage, caused by CP. Huaier polysaccharide (HP-1), an extraction of Trametes robiniophila Murr, with a molecular weight of 3 × 104 Da. Previous studies have shown that HP-1, exhibits anti-tumor potential and immunomodulatory effects. We hypothesized that HP-1 has the effect of attenuating the nephrotoxicity caused by CP chemotherapy and protecting renal function. Through our experiments, we observed that HP-1 can attenuate the level of oxidative stress, inflammation and mitochondrial dysfunction, thereby reducing kidney damage. In vitro, we observed that HP-1 significantly inhibits CP-induced renal tubular cell apoptosis and cell cycle arrest. In addition, HP-1 also affects the expression level of the protein by regulating the PI3K/Akt/mTOR signaling pathway and thus attenuates the side effects induced by cisplatin. Therefore, HP-1 may be a potential drug for preventing CP-induced renal damage.

Structural characterization and anti-alcoholic liver injury activity of a polysaccharide from Coriolus versicolor mycelia.

Polysaccharopeptide (PSP) from the medicinal mushroom Coriolus versicolor has been widely used in Asia as an adjunctive immunotherapy for treating cancers and liver diseases. However, the composition and structure of bioactive components in PSP remain elusive. Herein, we purified a hepatoprotective polysaccharide (PSP-1b1) with a molecular weight of 21.7 kDa from C. versicolor mycelia in submerged culture. PSP-1b1 consists of fucose, galactose, xylose, mannose, glucuronic acid and glucose at a relative molar ratio of 0.16:0.60:0.02:0.55:0.04:1.00. Structural features were investigated by methylation and gas chromatography-mass spectrometry, Fourier transform infrared spectroscopy and nuclear magnetic resonance spectroscopy. The PSP-1b1 backbone consists of →4)-α-Galp-(1 → 4)-α-Galp-(1 → 2)-α-Manp-(1 → 4)-α-Galp-(1 → 2)-α-Manp-(1 → 4)-α-Galp-(1 → 4)-α-Galp-(1 → 2)-α-Manp-(1 → 4)-α-Galp-(1 → 2)-α-Manp-(1 → 4)→, with branches of α-1,6-Manp, ß-1,6-Glcp, ß-1,3,6-Glcp, α-1,3-Manp, α-1,6-Galp, α-1,3-Fucp, T-α-Glcp and T-α-Galp on the O-6 position of α-Manp of the main chain, and secondary branches linked to the O-6 position of ß-Glcp of the major branch. Treatment with PSK-1b1 (80 and 160 mg/kg/day) resulted in hepatoprotective effects against alcohol-induced liver injury in mice by reducing oxidative stress and modulating immunity.

Mechanical, physical and chemical characterisation of mycelium-based composites with different types of lignocellulosic substrates.

The current physical goods economy produces materials by extracting finite valuable resources without taking their end of the life and environmental impact into account. Mycelium-based materials offer an alternative fabrication paradigm, based on the growth of materials rather than on extraction. Agricultural residue fibres are inoculated with fungal mycelium, which form an interwoven three-dimensional filamentous network binding the feedstock into a lightweight material. The mycelium-based material is heat-killed after the growing process. In this paper, we investigate the production process, the mechanical, physical and chemical properties of mycelium-based composites made with different types of lignocellulosic reinforcement fibres combined with a white rot fungus, Trametes versicolor. This is the first study reporting the dry density, the Young's modulus, the compressive stiffness, the stress-strain curves, the thermal conductivity, the water absorption rate and a FTIR analyse of mycelium-based composites by making use of a fully disclosed protocol with T. versicolor and five different type of fibres (hemp, flax, flax waste, softwood, straw) and fibre processings (loose, chopped, dust, pre-compressed and tow). The thermal conductivity and water absorption coefficient of the mycelium composites with flax, hemp, and straw have an overall good insulation behaviour in all the aspects compared to conventional materials such as rock wool, glass wool and extruded polystyrene. The conducted tests reveal that the mechanical performance of the mycelium-based composites depends more on the fibre processing (loose, chopped, pre-compressed, and tow), and size than on the chemical composition of the fibres. These experimental results show that mycelium-composites can fulfil the requirements of thermal insulation and have the potential to replace fosile-based composites. The methology used to evaluate the suitability and selection of organic waste-streams proved to be effective for the mycelium-material manufacturing applications.

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.

Antifungal Activity against Botrytis cinerea of 2,6-Dimethoxy-4-(phenylimino)cyclohexa-2,5-dienone Derivatives.

In this work the enzyme laccase from Trametes versicolor was used to synthetize 2,6-dimethoxy-4-(phenylimino)cyclohexa-2,5-dienone derivatives. Ten products with different substitutions in the aromatic ring were synthetized and characterized using ¹H- and 13C-NMR and mass spectrometry. The 3,5-dichlorinated compound showed highest antifungal activity against the phytopathogen Botrytis cinerea, while the p-methoxylated compound had the lowest activity; however, the antifungal activity of the products was higher than the activity of the substrates of the reactions. Finally, the results suggested that these compounds produced damage in the fungal cell wall.

Microbial Asymmetric Functionalization of ß-Cyclocitral-Derived Tetramethyl-Substituted γ-Lactone.

Searching for the new anticancer compounds we prepared three new ß-cyclocitral-derived hydroxyl-γ-lactones by microbial hydroxylation of tetramethyl-substituted bicyclic γ-lactone. The substrate was transformed by the enzymatic system of filamentous fungi. Three out of fifteen strains were selected as effective biocatalysts (Fusarium culmorum AM10, Armillaria mellea AM296, Trametes versicolor AM536). The hydroxylation processes were not only regioselective but also stereoselective. The hydroxylation products of each secondary carbon atom in the cyclohexane ring were obtained by the application of the selected fungal strains. The Fusarium culmorum AM10 introduced the hydroxy function at C-3 and C-4, Armillaria mellea AM296 incorporated the hydroxy function at C-3 and C-5 and Trametes versicolor AM536 transformed the substrate to the mixture of C-3, C-4 and C-5 hydroxylactones. The hydroxylactones obtained were enantiomericaly enriched (ee values in the range 17⁻99%). The in vitro antiproliferative activities of the functionalization products were also evaluated. Regardless of the hydroxy substituent location all tested lactones exhibited similar, significant activity towards selected cancer cell lines (IC50 in the range 22.8⁻33.9 µg/mL).

Huaier n-butanol extract suppresses proliferation and metastasis of gastric cancer via c-Myc-Bmi1 axis.

Gastric cancer (GC) ranks as the third leading cause of cancer-related mortality worldwide, and approximately 42% of all cases diagnosed each year worldwide are diagnosed in China. A large number of clinical applications have revealed that Trametes robiniophila Μurr. (Huaier) exhibits an anti-tumour effect. However, loss of the bioactive components of Huaier during the extraction procedure with water is unavoidable, and the underlying mechanism of the anti-cancer effect of Huaier remains poorly understood. In this study, we investigated the anti-cancer effect of Huaier n-butanol extract, which contained 51.4% total flavonoids, on HGC27, MGC803, and AGS human GC cell lines in vitro. At a low concentration, Huaier n-butanol extract inhibited the growth of these GC cell types, induced cell cycle arrest and reduced cell metastasis. Moreover, Huaier n-butanol extract suppressed the c-Myc-Bmi1 signalling pathway, and overexpression of Bmi1 reversed the effects of Huaier n-butanol extract on GC cells. Thus, our findings indicate that Huaier n-butanol extract suppresses the proliferation and metastasis of GC cells via a c-Myc-Bmi1-mediated approach, providing a new perspective for our understanding of the anti-tumour effects of Huaier. These results suggest that Huaier n-butanol extract could be an attractive therapeutic adjuvant for the treatment of human GC.

An immune-stimulating proteoglycan from the medicinal mushroom Huaier up-regulates NF-κB and MAPK signaling via Toll-like receptor 4.

Trametes robiniophila Murr. (Huaier) is a mushroom with a long history of use as a medicinal ingredient in China and exhibits good clinical efficacy in cancer management. However, the antitumor components of Huaier and the underlying molecular mechanisms remain poorly understood. Here, we isolated a proteoglycan with a molecular mass of ∼5.59 × 104 Da from Huaier aqueous extract. We named this proteoglycan TPG-1, and using FTIR and additional biochemical analyses, we determined that its total carbohydrate and protein compositions are 43.9 and 41.2%, respectively. Using biochemical assays and immunoblotting, we found that exposing murine RAW264.7 macrophages to TPG-1 promotes the production of nitric oxide (NO), tumor necrosis factor α (TNFα), and interleukin-6 (IL-6) through Toll-like receptor 4 (TLR4)-dependent activation of NF-κB and mitogen-activated protein kinase (MAPK) signaling. Of note, the TPG-1 treatment significantly inhibited the tumorigenesis of human hepatoma HepG2 cells likely at least in part by increasing serum levels of TNFα and promoting leukocyte infiltration into tumors in nude mice. TPG-1 also exhibited good antitumor activity in hepatoma H22-bearing mice and had no obvious adverse effects in these mice. We conclude that TPG-1 exerts antitumor activity partially through an immune-potentiating effect due to activation of the TLR4-NF-κB/MAPK signaling cassette. Therefore, TPG-1 may be a promising candidate drug for cancer immunotherapy. This study has identified the TPG-1 proteoglycan as an antitumor agent and provided insights into TPG-1's molecular mechanism, suggesting a potential utility for applying this agent in cancer therapy.