A new immunomodulatory protein from Ganoderma microsporum inhibits epidermal growth factor mediated migration and invasion in A549 lung cancer cells

Ganoderma microsporum immunomodulatory protein combined with KRASG12C inhibitor impedes intracellular AKT/ERK network to suppress lung cancer cells with KRAS mutation

KRAS mutations are tightly associated with lung cancer progression. Despite the unprecedented clinical success of KRASG12C inhibitors, recurrent mechanisms of resistance and other KRAS mutations require further therapeutic approaches. GMI, a protein from the medicinal mushroom Ganoderma microsporum, possesses antitumor activity; whereas, the biological function of GMI on regulating KRAS mutant lung cancer cells remains unknown. Herein, RNA-sequencing and bioinformatics showed that GMI may regulate KRAS-modulated MAPK and PI3K-AKT pathways in A549 (KRASG12S) cells. Further experiments demonstrated that GMI inhibited KRAS activation and suppressed ERK1/2 and AKT signaling in A549 cells. Intriguingly, GMI inhibited AKT signaling but increased phosphorylation of ERK in H358 (KRASG12C) cells. GMI significantly suppressed tumor growth in LLC1 cells-allograft and H358 cells-xenograft mice. GMI showed a synergistic effect with KRASG12C inhibitors in inhibiting cell growth, KRAS activation and KRAS-mediated downstream signaling, leading to apoptosis in H358 cells. Combination of GMI and KRASG12C inhibitor, AMG 510, resulted in more durable inhibition of tumor growth and KRAS activity in H358 cells-xenograft mice. This study highlights the potential of GMI, a dietary fungal protein, as a viable therapeutic avenue for KRAS-mutant lung cancer in combination with KRASG12C inhibitors.

Identification a novel Ganoderma FIP gene from Ganoderma capense and its functional expression in Pichia pastoris

Ganoderma capense is a precious medicinal fungus in China. In this study, a novel fungal immunomodulatory protein gene, named as FIP-gca, was cloned from G. capense by homologous cloning. Sequencing analysis indicated that FIP-gca was composed of 336 bp, which encoded a polypeptide of 110 amino acids. Protein sequence blasting and phylogenetic analysis showed that FIP-gca shared homology with other Ganoderma FIPs. FIP-gca was effectively expressed in Pichia pastoris GS115 at an expression level of 166.8 mg/L and purified using HisTrap™ fast-flow prepack columns. The immunomodulation capacity of rFIP-gca was demonstrated by that rFIP-gca could obviously stimulate cell proliferation and increase IL-2 secretion of murine spleen lymphocytes. Besides, antitumor activity of rFIP-gca towards human stomach cancer AGS cell line was evaluated in vitro. Cell wound scratch assay proved that rFIP-gca could inhibit migration of AGS cells. And flow cytometry assay revealed that rFIP-gca could significantly induce apoptosis of AGS cells. rFIP-gca was able to induce 18.12% and 22.29% cell apoptosis at 0.3 μM and 0.6 μM, respectively. Conclusively, the novel FIP-gca gene from G. capense has been functionally expressed in Pichia and rFIP-gca exhibited ideal immunomodulation and anti-tumour activities, which implies its potential application and study in future.

GMI, a Ganoderma microsporum protein, abolishes focal adhesion network to reduce cell migration and metastasis of lung cancer

BACKGROUND

Cancer metastasis is a major cause of cancer-related deaths, emphasizing the urgent need for effective therapies. Although it has been shown that GMI, a fungal protein from Ganoderma microsporum, could suppress primary tumor growth in a wide spectrum of cancer types, it is still unclear whether GMI exhibits anti-metastasis properties, particularly in lung cancers. Further investigation is needed.

AIMS AND OBJECTIVES

The objective of this study is to investigate the potential inhibitory effects of GMI on lung cancer metastasis in vivo. Utilizing systematic and comprehensive approaches, our research aims to elucidate the underlying molecular mechanisms responsible for the anti-metastatic effects.

MATERIALS AND METHODS

In vitro migration and cell adhesion assays addressed the epithelial-to-mesenchymal transition (EMT)-related phenotype. Proteomic and bioinformatic analyses identified the GMI-regulated proteins and cellular responses. GMI-treated LLC1-bearing mice were analyzed using IVIS Spectrum to assess the anti-metastatic effect.

KEY FINDINGS

GMI inhibits EMT as well as cell migration. GMI disrupts cell adhesion and downregulates integrin, resulting in inhibition of phosphorylated FAK. GMI induces macropinocytosis and lysosome-mediated degradation of integrin αv, α5, α6 and β1. GMI downregulates Slug via inhibition of FAK activity, which in turn enhances expressions of epithelial-related markers and decreases cell mobility. Mechanistically, GMI-induced FAK inhibition engenders MDM2 expression and enhances MDM2/p21/Slug complex formation, leading to Slug degradation. GMI treatment reduces the metastatic pulmonary lesion and prolongs the survival of LLC1-bearing mice.

SIGNIFICANCE

Our findings highlight GMI as a promising therapeutic candidate for metastatic lung cancers, offering potential avenues for further research and drug development.

Ganoderma microsporum immunomodulatory protein as an extracellular epidermal growth factor receptor (EGFR) degrader for suppressing EGFR-positive lung cancer cells

Epidermal growth factor receptor (EGFR) abnormalities relevant to tumor progression. A newly developed strategy for cancer therapy is induction of EGFR degradation. GMI, an immunomodulatory protein from the medicinal mushroom Ganoderma microsporum, exhibits anticancer activity. However, its role in the intracellular trafficking and degradation of EGFR remains unclear. In this study, we discovered that GMI inhibits the phosphorylation of multiple tyrosine kinases. Specifically, GMI was discovered to suppress lung cancer cells harboring both wild-type and mutant EGFR by inhibiting EGFR dimerization and eliminating EGFR-mediated signaling. Functional studies revealed that GMI binds to the extracellular segment of EGFR. GMI interacts with EGFR to induce phosphorylation of EGFR at tyrosine1045, which triggers clathrin-dependent endocytosis and degradation of EGFR. Furthermore, in the mouse models, GMI was discovered to suppress tumor growth. Knockdown of EGFR in lung cancer cells abolishes GMI's anticancer activity in vivo and in vitro. Our results reveal the interaction mechanisms through which GMI induces EGFR degradation and abolishes EGFR-mediated intracellular pathway. Our study indicates that GMI is an EGFR degrader for inhibiting EGFR-expressing tumor growth.

Characterization, Recombinant Production, and Bioactivity of a Novel Immunomodulatory Protein from Hypsizygus marmoreus

A novel fungal immunomodulatory protein (FIP), identified as FIP-hma, was discovered in the genome of an edible mushroom Hypsizygus marmoreus. Bioinformatics analysis suggested FIP-hma contained the cerato-platanin (CP) conserved domain and was categorized into Cerato-type FIP. In phylogenetic analysis, FIP-hma was clustered into a new branch of the FIP family, displaying large system divergence from most of the other FIPs. The higher gene expression of FIP-hma was observed during the vegetative growth stages than that during the reproductive growth stages. In addition, the cDNA sequence of FIP-hma was cloned and successfully expressed in Escherichia coli (E. coli) BL21(DE3). The recombinant protein of FIP-hma (rFIP-hma) was neatly purified and isolated by Ni-NTA and SUMO-Protease. The iNOS, IL-6, IL-1β, and TNF-α levels of RAW 264.7 macrophages were upregulated by rFIP-hma, indicating its activation of an immune response by regulating central cytokines. No cytotoxic effects were observed in an MTT test. The findings of this work discovered a novel immunoregulatory protein from H. marmoreus, provided a systematic bioinformatic profile, suggested an effective approach for its heterologous recombinant production, and reported its potent immunoregulatory activity in macrophages. This study sheds light on the physiological function research of FIPs and their further industrial utilization.

Isolation, Purification, and Antitumor Activity of a Novel Active Protein from Antrodia cinnamomea Liquid Fermentation Mycelia

Antrodia cinnamomea, a rare medicinal fungus endemic to Taiwan, contains numerous active components and displays strong antitumor and anti-inflammatory effects. We isolated and purified a novel A. cinnamomea active protein (termed ACAP) from liquid fermentation mycelia and evaluated its antitumor activity. A homogeneous protein-eluted fraction was obtained by anion exchange chromatography and gel filtration chromatography, and ACAP was identified based on the antitumor activity screening of this fraction. An in vitro assay of three tumor cell lines (HeLa, Hep G2, and Hepa 1-6) revealed significant antiproliferative effects of ACAP at low concentrations, with IC50 values of 13.10, 10.70, and 18.69 µg/mL, respectively. Flow cytometric analysis showed that ACAP induced late apoptosis of Hep G2 cells. The apoptosis rate of 50 µg/mL ACAP-treated cells (60%) was significantly (p < 0.01) more than that of the control. A Western blotting assay of apoptotic pathway proteins showed that ACAP significantly upregulated p53 and downregulated caspase-3 expression levels. Our findings indicate that ACAP has strong antitumor activity and the potential for development as a therapeutic agent and/or functional food.

Pathogen-derived peptides in drug targeting and its therapeutic approach

Peptides, short stretches of amino acids or small proteins that occupy a strategic position between proteins and amino acids, are readily accessible by chemical and biological methods. With ideal properties for forming high-affinity and specific interactions with host target proteins, they have established an important niche in the drug development spectrum complementing small molecule and biological therapeutics. Among the most successful biomedicines in use today, peptide-based drugs show great promise. This, coupled with recent advances in synthetic and nanochemical biology, has led to the creation of tailor-made peptide therapeutics for improved biocompatibility. This review presents an overview of the latest research on pathogen-derived, host-cell-interacting peptides. It also highlights strategies for using peptide-based therapeutics that address cellular transport challenges through the introduction of nanoparticles that serve as platforms to facilitate the delivery of peptide biologics and therapeutics for treating various inflammatory diseases. Finally, this paper describes future perspectives, specific pathogen-based peptides that can enhance specificity, efficiency, and capacity in functional peptide-based therapeutics, which are in the spotlight as new treatment alternatives for various diseases, and also presents verified sequences and targets that can increase chemical and pharmacological value.

GMI, Ganoderma microsporum protein, suppresses cell mobility and increases temozolomide sensitivity through induction of Slug degradation in glioblastoma multiforme cells

Glioblastoma multiforme (GBM), which is a malignant primary brain tumor, is the cancer that spreads most aggressively into the adjacent brain tissue. Patients with metastatic GBM have a poor chance of survival. In this study, we examined the anti-GBM mobility effect of small protein, called GMI, which is cloned and purified from Ganoderma microsporum. Proteomic profiles showed that GMI-mediated proteins were involved in cell motility and cell growth functions. Specifically, we demonstrated that GMI significantly suppressed cell migration and invasion of GBM cells. GMI combined with temozolomide (TMZ), which is a traditional chemotherapeutic agent for GBM treatment, synergistically inhibited motility in GBM cells. Mechanistically, we demonstrated that GMI induced proteasome-dependent degradation of Slug, which is a critical transcription factor, is frequently linked to metastasis and drug resistance in GBM. Knockdown of Slug reduced cell viability and colony formation of GBM cells but enhanced TMZ-suppressed cell migration and viability. The results of this study show that targeting Slug degradation is involved in GMI-suppressed mobility of GBM cells. Moreover, GMI may be a potential supplementary agent for the suppression of GBM.

GMI, a protein from Ganoderma microsporum, induces ACE2 degradation to alleviate infection of SARS-CoV-2 Spike-pseudotyped virus

BACKGROUND

Severe Acute Respiratory Syndrome Coronavirus Type 2 (SARS-CoV-2) induces a global serious pandemic and is responsible for over 4 million human deaths. Currently, although various vaccines have been developed, humans can still get SARS-CoV-2 infection after being vaccinated. Therefore, the blocking of SARS-CoV-2 infection may be potential therapeutic strategies. Ganoderma microsporum immunomodulatory protein (GMI), a small fungal protein, is cloned from Ganoderma microsporum. It exhibits anti-cancer and immunomodulatory functions. Currently, it is still unclear whether GMI involves in interfering with viral infection.

PURPOSE

This study aimed to examine the potential functions and mechanisms of GMI on inhibiting SARS-CoV-2 pseudovirus infection.

METHODS

The effects of GMI were examined in vitro on ACE2 overexpressing HEK293T (HEK293T/ACE2) cells exposed to SARS-CoV-2 Spike lentiviral pseudovirus encoding a green fluorescent protein (GFP) gene. The infection efficacy was determined using fluorescence microscopy and flow cytometry. The protein level of ACE2 was verified by Western blot. The effects of GMI on cell viability of HEK293T/ACE2 and lung epithelial WI38-2RA cells were determined by MTT assay. Mice received GMI via nebulizer.

RESULTS

GMI did not affect the cell viability of HEK293T/ACE2, WI38-2RA and macrophages. Functional studies showed that GMI inhibited GFP expressing SARS-CoV-2 pseudovirus from infecting HEK293T/ACE2 cells. GMI slightly interfered the interaction between ACE2 and Spike protein. GMI interacted with S2 domain of Spike protein. Specifically, GMI dramatically reduced ACE2 expression in HEK293T/ACE2 and WI38-2RA cells. Mechanistically, GMI induced ACE2 degradation via activating protein degradation system, including proteasome and lysosome. Abolishing proteasome and lysosome by MG132 and bafilomycin A1, respectively, rescued GMI-reduced ACE2 levels. In addition, GMI triggered dynamin and lipid raft-mediated ACE2 endocytosis. ACE2 levels were downregulated in the lung tissue after the mice inhaling GMI.

CONCLUSIONS

GMI prevents SARS-CoV-2 pseudovirus infection via induction of ACE2 degradation in host cells. Our findings suggest that GMI will be a potential prevention agent to alleviate SARS-CoV-2 infection.

Immunomodulatory protein from ganoderma microsporum protects against oxidative damages and cognitive impairments after traumatic brain injury

A traumatic brain injury (TBI) causes abnormal proliferation of neuroglial cells, and over-release of glutamate induces oxidative stress and inflammation and leads to neuronal death, memory deficits, and even death if the condition is severe. There is currently no effective treatment for TBI. Recent interests have focused on the benefits of supplements or natural products like Ganoderma. Studies have indicated that immunomodulatory protein from Ganoderma microsporum (GMI) inhibits oxidative stress in lung cancer cells A549 and induces cancer cell death by causing intracellular autophagy. However, no evidence has shown the application of GMI on TBI. Thus, this study addressed whether GMI could be used to prevent or treat TBI through its anti-inflammation and antioxidative effects. We used glutamate-induced excitotoxicity as in vitro model and penetrating brain injury as in vivo model of TBI. We found that GMI inhibits the generation of intracellular reactive oxygen species and reduces neuronal death in cortical neurons against glutamate excitotoxicity. In neurite injury assay, GMI promotes neurite regeneration, the length of the regenerated neurite was even longer than that of the control group. The animal data show that GMI alleviates TBI-induced spatial memory deficits, expedites the restoration of the injured areas, induces the secretion of brain-derived neurotrophic factors, increases the superoxide dismutase 1 (SOD-1) and lowers the astroglial proliferation. It is the first paper to apply GMI to brain-injured diseases and confirms that GMI reduces oxidative stress caused by TBI and improves neurocognitive function. Moreover, the effects show that prevention is better than treatment. Thus, this study provides a potential treatment in naturopathy against TBI.

Mushrooms as Potential Sources of Active Metabolites and Medicines

Background

Mushrooms exist as an integral and vital component of the ecosystem and are very precious fungi. Mushrooms have been traditionally used in herbal medicines for many centuries.

Scope and Approach

There are a variety of medicinal mushrooms mentioned in the current work such as Agaricus, Amanita, Calocybe, Cantharellus, Cordyceps, Coprinus, Cortinarius, Ganoderma, Grifola, Huitlacoche, Hydnum, Lentinus, Morchella, Pleurotus, Rigidoporus, Tremella, Trametes sp., etc., which play a vital role in various diseases because of several metabolic components and nutritional values. Medicinal mushrooms can be identified morphologically on the basis of their size, color (white, black, yellow, brown, cream, pink and purple-brown, etc.), chemical reactions, consistency of the stalk and cap, mode of attachment of the gills to the stalk, and spore color and mass, and further identified at a molecular level by Internal Transcribed Spacer (ITS) regions of gene sequencing. There are also other methods that have recently begun to be used for the identification of mushrooms such as high-pressure liquid chromatography (HPLC), nuclear magnetic resonance spectroscopy (NMR), microscopy, thin-layer chromatography (TLC), DNA sequencing, gas chromatography-mass spectrometry (GC-MS), chemical finger printing, ultra-performance liquid chromatography (UPLC), fourier transform infrared spectroscopy (FTIR), liquid chromatography quadrupole time-of-flight mass spectrometry (LCMS-TOF) and high-performance thin-layer chromatography (HPTLC). Lately, the matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) technique is also used for the identification of fungi.

Key Finding and Conclusion

Medicinal mushrooms possess various biological activities like anti-oxidant, anti-cancer, anti-inflammatory, anti-aging, anti-tumor, anti-viral, anti-parasitic, anti-microbial, hepatoprotective, anti-HIV, anti-diabetic, and many others that will be mentioned in this article. This manuscript will provide future direction, action mechanisms, applications, and the recent collective information of medicinal mushrooms. In addition to many unknown metabolites and patented active metabolites are also included.

Ganoderma immunomodulatory proteins: mushrooming functional FIPs

Fungal immunomodulatory protein (FIP) is a novel functional protein family with specific immunomodulatory activity identified from several macro-fungi. A variety of biological activities of FIPs have been reported, such as anti-allergy, anti-tumor, mitogenic activity, and immunomodulation. Among all known FIPs, the firstly discovered FIP was isolated from Ganoderma lucidum, and most FIP members were from Ganoderma genus. Compared with other FIPs, Ganoderma FIPs possess some advantageous bioactivities, like stronger anti-tumor activity. Therein, gene sequences, protein structural features, biofunctions, and recombinant expression of Ganoderma FIPs were summarized and addressed, focusing on elucidating their anti-tumor activity and molecular mechanisms. Combined with current advances, development potential and application of Ganoderma FIPs were also prospected. KEY POINTS: • More than a dozen of reported FIPs are identified from Ganoderma species. • Ganoderma immunomodulatory proteins have superior anti-tumor activity with promising prospects and application. • Current review comprehensively addresses characterization, biofunctions, and anti-tumor mechanisms of Ganoderma FIPs.

Pro-Health and Anti-Cancer Activity of Fungal Fractions Isolated from Milk-Supplemented Cultures of Lentinus (Pleurotus) Sajor-caju

The present study aimed to demonstrate Lentinus (formerly Pleurotus) sajor-caju (PSC) as a good source of pro-health substances. It has also shown that supplementation of its culture medium with cow milk may further improve its beneficial properties. Intracellular fractions from fungi grown on a medium supplemented with cow milk were analyzed using various biochemical methods for determination of the nutrient composition. Furthermore, anti-cancer properties of selected extracts were investigated on colorectal cancer cell lines (HT-29, LS 180, and SW948) in vitro. Biochemical analysis showed enrichment in health-enhancing compounds, such as proteins or polysaccharides (about 3.5- and 4.5-fold increase in concentration of proteins and carbohydratesin extracts of mycelia cultured on whole milk (PSC2-I), respectively), with a decrease in the level of free radicals (10-fold decrease in extract grown on milk and medium mixture (1:1) (PSC3-II)), which was related to increased catalase and superoxide dismutase activity (7.5-fold increase in catalase activity and 5-fold in SOD activity in PSC3-II compared to the control). Moreover, the viability of the cancer cells was diminished (to 60.0 ± 6.8% and 40.0 ± 8.6% of the control, on HT-29 and SW948 cells, respectively), along with pro-apoptotic (to 18.8 ± 11.8 and 14.7 ± 8.0% towards LS 180 and SW948 cells, respectively) and NO-secreting effects (about 2-fold increase) of the extracts. This study suggests that PSC has multiple nutritional and anti-cancer properties and can be used as a source of healthy biomolecules in modern medicine or functional foods.

GMI, an Immunomodulatory Peptide from Ganoderma microsporum, Restrains Periprosthetic Joint Infections via Modulating the Functions of Myeloid-Derived Suppressor Cells and Effector T Cells

Periprosthetic joint infections (PJIs) caused by Staphylococcus aureus infection are difficult to treat due to antibiotic resistance. It is known that the biofilms from methicillin-resistant S. aureus (MRSA) promote expansion of myeloid-derived suppressor cells (MDSCs) to suppress T-cell proliferation and benefit bacterial infections. This study finds that GMI, a fungal immunomodulatory peptide isolated from Ganoderma microsporum, suppresses MDSC expansion to promote the proliferation of cytotoxic T cells. The enhancement is likely attributed to increased expression of IL-6 and TNF-α and reduction in ROS expression. Similar beneficial effects of GMI on the suppression of MDSC expansion and IL-6 expression are also observed in the whole blood and reduces the accumulation of MDSCs in the infected bone region in a mouse PJI infection model. This study shows that GMI is potentially useful for treating S. aureus-induced PJIs.

Identification and Functional Characterization of a Novel Immunomodulatory Protein From Morchella conica SH

A novel fungal immunomodulatory protein (FIP) was found in the precious medical and edible mushroom Morchella conica SH, defined as FIP-mco, which belongs to the FIP family. Phylogenetic analyses of FIPs from different origins were performed using Neighbor-Joining method. It was found that FIP-mco belonged to a new branch of the FIP family and may evolved from a different ancestor compared with most other FIPs. The cDNA sequence of FIP-mco was cloned and expressed in the yeast Pichia Pastoris X33. The recombinant protein of FIP-mco (rFIP-mco) was purified by agarose Ni chromatography and determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and Western blot analysis. The protein rFIP-mco could significantly suppress the proliferation of A549 and HepG2 cells at the concentration of 15 and 5 μg/ml, respectively, and inhibited the migration and invasion of human A549 and HepG2 cells at the concentration of 15 and 30 μg/ml respectively in vitro. Further, rFIP-mco can significantly reduce the expression levels of TNF-α, IL-1β, and IL-6 in the THP1 cells (human myeloid leukemia mononuclear cells). In order to explore the potential mechanism of the cytotoxicity effect of rFIP-mco on A549 and HepG2 cells, cell cycle and apoptosis assay in the two cancer cells were conducted. The results demonstrated that G0/G1 to S-phase arrest and increased apoptosis may contribute to the proliferation inhibition by rFIP-mco in the two cancer cells. Molecular mechanism of rFIP-mco's reduction effect on the inflammatory cytokines was also studied by suppression of the NF-κB signaling pathway. It showed that suppression of NF-κB signaling is responsible for the reduction of inflammatory cytokines by rFIP-mco. The results indicated the prospect of FIP-mco from M. conica SH as an effective and feasible source for cancer therapeutic studies and medical applications.

New advances and potentials of fungal immunomodulatory proteins for therapeutic purposes

Fungal immunomodulatory proteins (FIPs) are fascinating small and heat-stable bioactive proteins in a distinct protein family due to similarities in their structures and sequences. They are found in fungi, including the fruiting bodies producing fungi comprised of culinary and medicinal mushrooms. Structurally, most FIPs exist as homodimers; each subunit consisting of an N-terminal α-helix dimerization and a C-terminal fibronectin III domain. Increasing numbers of identified FIPs from either different or same fungal species clearly indicates the growing research interests into its medicinal properties which include immunomodulatory, anti-inflammation, anti-allergy, and anticancer. Most FIPs increased IFN-γ production in peripheral blood mononuclear cells, potentially exerting immunomodulatory and anti-inflammatory effects by inhibiting overproduction of T helper-2 (Th2) cytokines common in an allergy reaction. Recently, FIP from Ganoderma microsporum (FIP-gmi) was shown to promote neurite outgrowth for potential therapeutic applications in neuro-disorders. This review discussed FIPs' structural and protein characteristics, their recombinant protein production for functional studies, and the recent advances in their development and applications as pharmaceutics and functional foods.

Current Understanding of the Structure and Function of Fungal Immunomodulatory Proteins

Fungal immunomodulatory proteins (FIPs) are a group of proteins found in fungi, which are extensively studied for their immunomodulatory activity. Currently, more than 38 types of FIPs have been described. Based on their conserved structure and protein identity, FIPs can be classified into five subgroups: Fve-type FIPs (Pfam PF09259), Cerato-type FIPs (Pfam PF07249), PCP-like FIPs, TFP-like FIPs, and unclassified FIPs. Among the five subgroups, Fve-type FIPs are the most studied for their hemagglutinating, immunomodulating, and anti-cancer properties. In general, these small proteins consist of 110–125 amino acids, with a molecular weight of ~13 kDa. The other four subgroups are relatively less studied, but also show a noticeable influence on immune cells. In this review, we summarized the protein modifications, 3-dimensional structures and bioactivities of all types of FIPs. Moreover, structure-function relationship of FIPs has been discussed, including relationship between carbohydrate binding module and hemagglutination, correlation of oligomerization and cytokine induction, relevance of glycosylation and lymphocyte activation. This summary and discussion may help gain comprehensive understanding of FIPs' working mechanisms and scope future studies.

Combination treatment of Src inhibitor Saracatinib with GMI, a Ganoderma microsporum immunomodulatory protein, induce synthetic lethality via autophagy and apoptosis in lung cancer cells

Saracatinib is an oral Src-kinase inhibitor and has been studied in preclinical models and clinical trials of cancer therapy. GMI, a fungal immunomodulatory protein from Ganoderma microsporum, possesses antitumor capacity. The aim of this study is to evaluate the cytotoxic effect of combination treatment with saracatinib and GMI on parental and pemetrexed-resistant lung cancer cells. Cotreatment with saracatinib and GMI induced synergistic and additive cytotoxic effect in A549 and A400 cells by annexin V/propidium iodide assay and combination index. Using western blot assay, saracatinib, and GMI combined treatment synergistically induced caspase-7 activation in A549 cells. Different from A549 cells, saracatinib and GMI cotreatment markedly increased LC3B-II in A400 cells. ATG5 silencing abolished the caspase-7 activation and reduced cell death in A549 cells after cotreatment. This is the first study to provide a novel strategy of treating lung cancer with or without drug resistance via combination treatment with GMI and saracatinib.

The Protective Role of GMI, an Immunomodulatory Protein From Ganoderma microsporum, on 5-Fluorouracil-Induced Oral and Intestinal Mucositis

5-Fluorouracil (5-FU) is used in the treatment of head and neck cancer patients. However, adverse effects experienced such as mucositis and poor appetite may lead to interruption in chemotherapy. The aim of this study is to evaluate the efficacy of GMI, one fungal immunomodulatory protein found in Ganoderma microsporum, for mucositis induced by 5-FU in a mouse model. Mice were administered 5-FU intraperitoneally for 4 days per cycle for a total of 2 chemotherapy cycles. In addition, mice were pretreated with GMI or phosphate-buffered saline 3 days before 5-FU intraperitoneal injection and daily until day 14. On histological analysis, GMI prevented 5-FU-induced damage to the intestinal mucosa and tongue epithelium. We also demonstrated that GMI enhanced the cytotoxicity of 5-FU in 2 oral cancer cell lines, while GMI could not promote this effect in an oral normal cell. In conclusion, GMI alleviates 5-FU-induced damage and decelerates cell death in normal alimentary tract tissue.

Nutritional and antioxidant potential of some wild edible mushrooms of Nagaland, India

Mushrooms are known to mankind since early human civilization and are gaining importance because of their nutritional and medicinal properties. Till date 37 wild edible mushrooms are reported from Nagaland. In this study, nutritional analysis including total phenolics, flavonoids and antioxidant activity was done for ten popular WEM species. Total protein content was found to be high which ranged from 62.27 g/100 g (Lentinus sajor-caju) to 18.77 g/100 g (Lentinus squarrosulus var. squarrosulus); total carbohydrate content ranged from 38.44 g/100 g (Lentinula edodes) to 5.31 g/100 g (Schizophyllum commune); reducing sugar content ranged from 7.81 g/100 g (Termitomyces heimii) to 2.33 g/100 g (S. commune). Crude fiber ranged from 11.1% (A. auricula-judae) to 1.71% (L. squarrosulus) and ash content ranged from 10.66% (L. squarrosulus) to 3.12% (L. squarrosulus var. squarrosulus). The highest phenolic content was observed in L. squarrosulus (18.7 g/100 g) and highest flavonoid content was observed in L. sulphureus (9.3 g/100 g). All the ten mushroom species exhibited antioxidant activity against DPPH free radical, but highest activity was recorded in L. tigrinus (47.5 μg/ml, IC50). Hence, mushrooms are valuable natural resource to mankind and should be exploited judiciously for the betterment of society.

Ganoderma: A Cancer Immunotherapy Review

Ganoderma is a significant source of natural fungal medicines and has been used for the treatment of various diseases for many years. However, the use of Ganoderma in cancer immunotherapy is poorly elucidated. In this study, we have analyzed 2,398 English-language papers and 6,968 Chinese-language papers published between 1987 and 2017 by using bibliometrics. A steady growth in the number of publications was observed before 2004, followed by an exponential increase between 2004 and 2017. The most common category for publications about Ganoderma was "Pharmacology & Pharmacy," in which immunomodulation (25.60%) and cancer treatment (21.40%) were the most popular subcategories. Moreover, we have provided an overview of the bioactive components and combinatorial immunomodulatory effects for the use of Ganoderma in the treatment of cancer, including the major pathways of immune cells. Immunomodulatory protein and polysaccharides are the key bioactive factors responsible for cancer immunotherapy, and the NF-κB and MAPK pathways are the most comprehensively investigated major pathways. Our results indicate that Ganoderma has a broad-spectrum application for the treatment of cancer through the regulation of the immune system. This review provides guidance for future research into the role of Ganoderma in cancer immunotherapy.

GMI, a fungal immunomodulatory protein from Ganoderma microsporum, induce apoptosis via β-catenin suppression in lung cancer cells

β-catenin is important in development of lung cancer. In our previous study, GMI, a fungal immunomodulatory protein, inhibits lung cancer cell survival. The aim of this study is to evaluate the effect of GMI on β-catenin inhibition and apoptosis induction. GMI induced apoptosis in lung cancer cells bearing wild-type and mutated EGFR. GMI did not reduce the β-catenin mRNA expression but suppressed the protein expressions of β-catenin that resulted in the transcriptional downregulation of its target genes: survivin and cyclin-D1. The transcriptional activation activity of β-catenin was demonstrated by TOPFLASH/FOPFLASH luciferase reporter assay. Inhibition of GSK-3β and proteasome blocked the inhibiting effect of GMI on β-catenin and its target genes. β-catenin silencing increased activation of apoptosis in GMI-treated H1355 cells. This is the first study to reveal the novel function of GMI in inducing apoptosis via β-catenin inhibition. These results provide a new potential of GMI in against lung cancer.

Anticancer, antioxidant, and antibacterial activities of low molecular weight bioactive subfractions isolated from cultures of wood degrading fungus Cerrena unicolor

The aim of this study is to investigate in vitro the anticancer, antioxidant, and antibacterial activities of three low molecular weight subfractions I, II and III isolated from secondary metabolites produced by the wood degrading fungus Cerrena unicolor. The present study demonstrated that the low molecular weight subfractions III exhibited the strongest inhibitory activity towards breast carcinoma cells MDA-MB-231, prostatic carcinoma cells PC3, and breast cancer cells MCF7 with the half-maximal inhibitory concentration (IC₅₀) value of 52,25 μg/mL, 60,66 μg/mL, and 54,92 μg/mL, respectively. The highest percentage of inhibition was noted at a concentration of 300 μg/mL in all the examined tumor lines. A significant percentage (59.08%) of ex-LMSIII inhibition of the MDA-MB-231 tumor line was reached at a concentration of 15 μg/ml, while the concentration applied did not affect normal human fibroblast cells. The low molecular weight subfraction III was the most effective and additionally showed the highest free radical 1,1-diphenyl-2-picryl-hydrazyl scavenging activity (IC₅₀ 20.39 μg/mL) followed by the low molecular weight subfraction I (IC₅₀ 64.14 μg/mL) and II (IC₅₀ 49.22 μg/mL). The antibacterial activity of the tested preparations was evaluated against three microorganisms: Bacillus subtilis, Staphylococcus aureus, and Escherichia coli. The MIC minimal inhibitory concentration (MIC) values for the low molecular weight subfraction I, II, and III showed a stronger inhibition effect on S. aureus than on B. subtilis and E. coli cells. The MIC values for the low molecular weight subfraction II against S. aureus, B. subtilis, and E. coli were 6.25, 12.5, and 100 mg/mL, respectively.

Anti-invasive and antiproliferative effects of Pleurotus ostreatus extract on acute leukemia cell lines

BACKGROUND

Currently, mushrooms have been used in traditional and folk medicines for their therapeutic activities, such as antibiotic, antitumor, anti-inflammatory, anticancer, antileukemic and immunomodulatory actions. This investigation evaluates the anti-invasive, antiproliferative and cytotoxic effects of Pleurotus ostreatus (Pleurotaceae) on leukemia cell lines.

METHODS

The proliferation of KG-1 cells was measured by using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay after treatment with gradient dilutions of P. ostreatus extract. Then, the minimum inhibitory concentration (MIC) of the extract was determined. Moreover, the proliferation of Jurkat cells and bone marrow mesenchymal stem cells (BMSCs), a cancerous cell line and normal body cells, respectively, was considered. The apoptotic morphology of treated KG-1 cells was evaluated with Giemsa staining. The invasion and migration of cells were evaluated using transwell invasion assay. Thereafter, the rates of apoptosis and necrosis were measured by using flow cytometry, and BAX and MMP-9 gene expression were evaluated using quantitative reverse transcription-polymerase chain reaction as apoptotic and metastatic genes, respectively.

RESULTS

The MIC of the extract was determined to be 1 mg/mL after 48 h. According to the results, the extract decreased the proliferation of leukemia cell lines (KG-1 and Jurkat cells) but had no antiproliferative effects on BMSCs. Moreover, KG-1 cell migration and MMP-9 gene expression decreased after the treatment, and the rate of apoptosis and BAX gene expression increased significantly.

CONCLUSIONS

According to the efficient therapeutic properties of P. ostreatus on leukemia cell lines, this mushroom could be introduced as a natural medicine to cure leukemic patients who suffer from the harmful side effects and enormous costs of chemotherapy.

Inhibitory effect of GMI, an immunomodulatory protein from Ganoderma microsporum, on myofibroblast activity and proinflammatory cytokines in human fibrotic buccal mucosal fibroblasts

Oral submucous fibrosis (OSF) has been indicated as one of the oral potentially malignant disorders. Epidemiological studies have attributed this pathological fibrosis to the habit of areca nuts chewing, which causes chronic inflammation and persistent activation of myofibroblasts in the oral cavity. Hence, it is crucial to find an effective intervention to ameliorate inflammation in order to prevent the malignant progression of OSF. In this study, we assessed the anti-inflammatory effect of the immunomodulatory protein, GMI, extracted from Ganoderma microsporum on the expression proinflammatory cytokines and the myofibroblast characteristics in human fibrotic buccal mucosal fibroblasts (fBMFs). Our results demonstrated that the expression level of interleukin (IL)-6 and IL-8 were decreased after exposure of GMI and the myofibroblast activities, including collagen gel contraction, migration, invasion, and wound healing abilities were inhibited as well. Furthermore, we confirmed these findings in the arecoline-stimulated BMFs. Consistent with the above findings, the expression of the myofibroblast marker α-smooth muscle actin and other fibrogenic markers, such as type I collagen, fibronectin, and vimentin in fBMFs were all reduced in a dose-dependent manner. Collectively, our data suggested that GMI suppressed the proinflammatory cytokines and myofibroblast features in fBMFs, and could serve as a promising and natural antifibrosis agent.

Purification and characterization of a novel ubiquitin-like antitumour protein with hemagglutinating and deoxyribonuclease activities from the edible mushroom Ramaria botrytis

A novel ubiquitin-like antitumour protein (RBUP) was isolated from fruiting bodies of the edible mushroom Ramaria botrytis. The protein was isolated with a purification protocol involving ion exchange chromatography on DEAE-Sepharose fast flow and gel filtration on Sephadex G-75. SDS-PAGE, Native-PAGE and ultracentrifugation analysis disclosed that RBUP was a monomeric protein with a molecular weight of 18.5 kDa. ESI-MS/MS demonstrated that it shared 69% amino acid sequence similarity with Coprinellus congregates ubiquitin (gi|136667). The protein exhibiting strong anticancer activity towards A549 cells. Analysis by employing AO/EB staining and Annexin V-FITC/PI detection indicated that the cytotoxic effect of RBUP was mediated through induction of apoptosis. Furthermore, RBUP displayed hemagglutinating and deoxyribonuclease activities. A temperature of 40 °C and pH of 7.0 were required for optimal DNase activity. Therefore, it was estimated that RBUP exerted its antitumour effect by inducing apoptosis, and its hemagglutinating and DNase activities were also thought to participate in this effect. These results demonstrated that RBUP was a multifunctional protein with potential medicinal applications.

Mushrooms: from nutrition to mycoremediation

Mushrooms are well known as important food items. The uses of mushrooms in the cuisine are manifolds and are being utilized for thousands of years in both Oriental and Occidental cultures. Medicinal properties of mushrooms show an immense potential as drugs for the treatment of various diseases as they are rich in a great variety of phytochemicals. In this review, we attempted to encompass the recent knowledge and scientific advancement about mushrooms and their utilization as food or curative properties, along with their natural ability to accumulate (heavy) metals/radionuclides, which leads to an important aspect of bioremediation. However, accumulation of heavy metals and radionuclides from natural or anthropogenic sources also involves potential nutritional hazards upon consumption. These hazards have been pointed out in this review incorporating a selection of the most recently published literature.

GMI ablates cancer stemness and cisplatin resistance in oral carcinomas stem cells through IL-6/Stat3 signaling inhibition

Cancer stem cells (CSCs) have been identified to exert tumor-initiating ability, resulting in the recurrence, metastasis and chemoresistance of oral squamous cell carcinomas. In the present study, we showed that GMI, an immunomodulatory protein from Ganoderma microsporum, induc ed a cytotoxic effect in oral carcinomas stem cells (OCSCs). Treatment of GMI dose-dependently inhibited the expression of CSC markers, including ALDH1 activity and CD44 positivity. Moreover, GMI suppressed the self-renewal property, colony formation, migration, and invasion abilities as well as potentiated chemo-sensitivity in OCSCs. Our results suggested that the tumor suppressive effect of GMI was mediated through inhibition of IL-6/Stat3 signaling pathway. Furthermore, tumor growth was reduced in mice bearing xenograft tumors after oral administration of GMI. Taken together, we demonstrated the anti-CSC effect of GMI in oral cancer and GMI may serve as a natural cisplatin adjuvant to prevent cancer recurrence.

Ganoderma lucidum targeting lung cancer signaling: A review

Lung cancer causes huge mortality to population, and pharmaceutical companies require new drugs as an alternative either synthetic or natural targeting lung cancer. The conventional therapies cause side effects, and therefore, natural products are used as a therapeutic candidate in lung cancer. Chemical diversity among natural products highlights the impact of evolution and survival of fittest. One such neglected natural product is Ganoderma lucidum used for promoting health and longevity for a longer time. The major bioconstituents of G. lucidum are mainly terpenes, polysaccharides, and proteins, which were explored for various activities ranging from apoptosis to autophagy. The bioconstituents of G. lucidum activate plasma membrane receptors and initiate various downstream signaling leading to nuclear factor-κB, phosphoinositide 3-kinase, Akt, and mammalian target of rapamycin in cancer. The bioconstituents regulate the expression of various genes involved in cell cycle, immune response, apoptosis, and autophagy in lung cancer. This review highlights the inextricable role of G. lucidum and its bioconstituents in lung cancer signaling for the first time.

Breaking the sporoderm of Ganoderma lucidum spores by combining chemical reaction with physical actuation

The hard and indissolvable sporoderm of Ganoderma lucidum spore (GLS) hinders the release of bioactive components that are significant to disease treatment and vitality enhancement. In this paper, a strategy to break sporoderm was proposed, in which the chemical reaction was cooperated with physical actuation (ultrasonication and refrigeration). Dealing with this chemicophysical treatment, the porous sporoderm of GLS was formed, which was confirmed by scanning electron microscope (SEM). The effect factors and mechanism of breaking sporoderm were discussed, and the efficiency of breaking sporoderm was evaluated by detecting the dissolution behaviour of inner triterpenoids in GLS. In addition, aiming to improve the solubility and stability of GLS product, the β-cyclodextrin was used to seal the holes on sporoderm of GLS product. The results show that the developed method is effective and feasible in producing high-bioactive and stable GLS product.

FIP-sch2, a new fungal immunomodulatory protein from Stachybotrys chlorohalonata, suppresses proliferation and migration in lung cancer cells

Fungal immunomodulatory protein (FIP)-sch2, an immunomodulatory protein identified in the ascomycete Stachybotrys chlorohalonata by a sequence similarity search, is a novel member of the FIP family. FIP-sch2 shares high sequence identity, structure, and evolutionary conservation with previously reported FIPs. It was satisfactorily expressed in Escherichia coli with a glutathione S-transferase (GST) tag and purified by GST-affinity magnetic beads. To characterize the direct antitumor effects, human lung adenocarcinoma A549 cells were treated with different concentrations of recombinant FIP (rFIP)-sch2 in vitro, and the results showed that rFIP-sch2 could reduce cell viability dose-dependently with a half-maximal inhibitory concentration (IC₅₀) of 9.48 μg/mL. Furthermore, rFIP-sch2 at 8 μg/mL could significantly induce apoptosis and interrupt migration in A549 cells. Notably, the antitumor effect of rFIP-sch2 was equivalent to that of rLZ-8 but was obviously increased compared to rFIP-fve. In addition, the exploration of the antitumor mechanism suggested that rFIP-sch2 induced lung cancer cell death by activating apoptosis and inhibiting migration. Our results indicated that rFIP-sch2 was a promising candidate for use in future cancer therapy.

Identification and Characterisation of a Novel Protein FIP-sch3 from Stachybotrys chartarum

In this study, a novel FIP named FIP-sch3 has been identified and characterised. FIP-sch3 was identified in the ascomycete Stachybotrys chartarum, making it the second FIP to be identified outside the order of Basidiomycota. Recombinant FIP-sch3 (rFIP-shc3) was produced in Escherichia coli and purified using GST-affinity magnetic beads. The bioactive characteristics of FIP-sch3 were compared to those of well-known FIPs LZ-8 from Ganoderma lucidum and FIP-fve from Flammulina velutipes, which were produced and purified using the same method. The purified rFIP-sch3 exhibited a broad spectrum of anti-tumour activity in several types of tumour cells but had no cytotoxicity in normal human embryonic kidney 293 cells. Assays that were implemented to study these properties indicated that rFIP-sch3 significantly suppressed cell proliferation, induced apoptosis and inhibited cell migration in human lung adenocarcinoma A549 cells. The anti-tumour effects of rFIP-sch3 in A549 cells were comparable to those of rLZ-8, but they were significantly greater than those of rFIP-fve. Molecular assays that were built on real-time PCR further revealed potential mechanisms related to apoptosis and migration and that underlie phenotypic effects. These results indicate that FIP-shc3 has a unique anti-tumour bioactive profile, as do other FIPs, which provide a foundation for further studies on anti-tumour mechanisms. Importantly, this study also had convenient access to FIP-sch3 with potential human therapeutic applications.

Immunomodulatory proteins FIP-gts and chloroquine induce caspase-independent cell death via autophagy for resensitizing cisplatin-resistant urothelial cancer cells

BACKGROUND

Chloroquine, a lysosomal inhibitor, is used for malaria, rheumatoid arthritis, and lupus erythematosus therapy. In our previous study, FIP-gts, an immunomodulatory protein from Ganoderma tsugae, inhibited cell viability in lung cancer cells and urothelial cancer cells. Urothelial carcinoma is the most common type of bladder cancer. Cisplatin resistance is an important issue in urothelial carcinoma therapy.

PURPOSE

The aim of this study is to investigate the effect of combination treatment with FIP-gts and chloroquine on cytotoxicity to resensitize the cisplatin-resistant cells.

METHODS

FIP-gts and chloroquine cytotoxicity were determined by evaluating CCK-8 assay. Cell death pathways, ROS and cell cycle arrested were analysed through flow cytometry and Western blot. ShRNA targeting to autophagy-related genes were tested to evaluate their autophagic cell death for resistant urothelial cells.

RESULTS

Using CCK-8 assay, chloroquine increased FIP-gts-induced cytotoxicity in parental and cisplatin-resistant urothelial cancer cell lines. On flow cytometry, chloroquine enhanced FIP-gts-mediated sub-G1 accumulation, annexin V positive signal and mitochondrial membrane potential loss. Caspase-3/PARP cascade and z-VAD-fmk were performed to prove that FIP-gts and chloroquine induced caspase-independent cell death. Using H2DCFDA staining and flow cytometry, FIP-gts and chloroquine did not induce ROS production. N-acetyl cysteine, a ROS scavenger, inhibited the cytotoxicity and LC3-II accumulation in FIP-gts and chloroquine-treated N/P cells. To elucidate the role of autophagy in caspase-independent cell death by FIP-gts and chloroquine, LC3 shRNA were used to inhibit autophagy in N/P cells. The capabilities of FIP-gts and chloroquine to induce cytotoxicity and sub-G1 phase accumulation were abolished in autophagy-defective cells. This is the first study to reveal the novel function of FIP-gts in triggering caspase-independent cell death in cisplatin-resistant urothelial cancer cells.

CONCLUSION

Chloroquine enhanced FIP-gts-induced autophagy dependent caspase-independent cell death via abundant autophagosome accumulation. Combination treatment with FIP-gts and chloroquine may provide a new strategy for urothelial cancer therapy.

Characterisation of a New Fungal Immunomodulatory Protein from Tiger Milk mushroom, Lignosus rhinocerotis

Lignosus rhinocerotis (Tiger milk mushroom) is an important folk medicine for indigenous peoples in Southeast Asia. We previously reported its de novo assembled 34.3 Mb genome encoding a repertoire of proteins including a putative bioactive fungal immunomodulatory protein. Here we report the cDNA of this new member (FIP-Lrh) with a homology range of 54–64% to FIPs from other mushroom species, the closest is with FIP-glu (LZ-8) (64%) from Ganoderma lucidum. The FIP-Lrh of 112 amino acids (12.59 kDa) has a relatively hydrophobic N-terminal. Its predicted 3-dimensional model has identical folding patterns to FIP-fve and contains a partially conserved and more positively charged carbohydrates binding pocket. Docking predictions of FIP-Lrh on 14 glycans commonly found on cellular surfaces showed the best binding energy of −3.98 kcal/mol to N-acetylgalactosamine and N-acetylglucosamine. Overexpression of a 14.9 kDa soluble 6xHisFIP-Lrh was achieved in pET-28a(+)/BL21 and the purified recombinant protein was sequence verified by LC-MS/MS (QTOF) analysis. The ability to haemagglutinate both mouse and human blood at concentration ≥0.34 μM, further demonstrated its lectin nature. In addition, the cytotoxic effect of 6xHisFIP-Lrh on MCF-7, HeLa and A549 cancer cell lines was detected at IC₅₀ of 0.34 μM, 0.58 μM and 0.60 μM, respectively.

Immunomodulatory Protein from Ganoderma microsporum Induces Pro-Death Autophagy through Akt-mTOR-p70S6K Pathway Inhibition in Multidrug Resistant Lung Cancer Cells

Chemoresistance in cancer therapy is an unfavorable prognostic factor in non-small cell lung cancer (NSCLC). Elevation of intracellular calcium level in multidrug resistant (MDR) sublines leads to sensitization of MDR sublines to cell death. We demonstrated that a fungal protein from Ganoderma microsporum, GMI, elevates the intracellular calcium level and reduces the growth of MDR subline via autophagy and apoptosis, regardless of p-glycoprotein (P-gp) overexpression, in mice xenograft tumors. In addition, we examined the roles of autophagy in the death of MDR A549 lung cancer sublines by GMI, thapsigargin (TG) and tunicamycin (TM) in vitro. Cytotoxicity of TG was inhibited by overexpressed P-gp. However, TM-induced death of MDR sublines was independent of P-gp level. Combinations of TG and TM with either docetaxel or vincristine showed no additional cytotoxic effects on MDR sublines. TG- and TM-mediated apoptosis of MDR sublines was demonstrated on Annexin-V assay and Western blot and repressed by pan-caspase inhibitor (Z-VAD-FMK). Treatment of MDR sublines with TG and TM also augmented autophagy with accumulation of LC3-II proteins, breakdown of p62 and formation of acidic vesicular organelles (AVOs). Inhibition of ATG5 by shRNA silencing significantly reduced autophagy and cell death but not apoptosis following TG or TM treatment. GMI treatment inhibited the phosphorylation of Akt/S473 and p70S6K/T389. Interestingly, the phosphorylation of ERK was not associated with GMI-induced autophagy. We conclude that autophagy plays a pro-death role in acquired MDR and upregulation of autophagy by GMI via Akt/mTOR inhibition provides a potential strategy for overcoming MDR in the treatment of lung cancers.