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

Integrin αV Inhibition by GMI, a Ganoderma Microsporum Immunomodulatory Protein, Abolish Stemness and Migration in EGFR-Mutated Lung Cancer Cells Resistant to Osimertinib

Integrins, the receptors of the extracellular matrix, are critical in the proliferation and metastasis of cancer cells. GMI, a Ganoderma microsporum immunomodulatory protein, possesses anticancer and antivirus abilities. The object of this study is to investigate the role of GMI in the integrins signaling pathway in lung cancer cells that harbor the EGFR L858R/T790M double mutation and osimertinib-resistance. Liquid chromatography-mass spectrometry and western blot assay were used to investigate the effect of GMI on inhibiting the protein expressions of integrins in H1975 cells. The migration ability and xenograft tumor growth of H1975 were suppressed by GMI. To elucidate the role of the integrin family in lung cancer resistant to osimertinib (AZD-9291, Tagrisso), H1975 cells were used to establish the osimertinib-resistant cells, named H1975/TR cells. The expressions of Integrin αV and stemness markers were much higher in H1975/TR cells than in H1975 cells. GMI suppressed cell viability, tumor spheroid growth, and the expressions of integrin αV and β1 in H1975/TR cells. Furthermore, GMI suppressed the expressions of stemness markers and formation of tumor spheres via blocking integrin αV signaling cascade. This is the first study to reveal the novel function of GMI in constraining cancer stem cells and migration by abolishing the integrin αV-related signaling pathway in EGFR-mutated and osimertinib-resistant lung cancer cells.

Regimen on Dnaja3 haploinsufficiency mediated sarcopenic obesity with imbalanced mitochondrial homeostasis and lipid metabolism

BACKGROUND

Sarcopenic obesity is characterized by excess fat mass and diminished muscular mass/function. DNAJA3, a mitochondrial co-chaperone protein, plays a crucial role in skeletal muscle development. GMI, an immunomodulatory protein, promotes myogenic differentiation through DNAJA3 activation. This study aims to elucidate the physiological effects of muscular Dnaja3 haploinsufficiency on mitochondrial dysfunction and dysregulated lipid metabolism and to assess the efficacy of GMI in rescuing sarcopenic obesity both in vitro and in vivo.

METHODS

We generated mouse strain with Dnaja3 heterozygosity (HSA-Dnaja3f/+) specifically in skeletal muscle. The body weight, body composition, and locomotor activity of WT and HSA-Dnaja3f/+ mice were examined. The isolated skeletal muscles and primary myoblasts from the WT and HSA-Dnaja3f/+ mice, at young or old age, were utilized to study the molecular mechanisms, mitochondrial respiration and ROS level, mitochondrial proteomes, and serological analyses, respectively. To evaluate the therapeutic efficacy of GMI, both short-term and long-term GMI treatment were administrated intraperitoneally to the HSA-Dnaja3f/+ young (4 weeks old) or adult (3 months old) mice for a duration of either 1 or 6 months, respectively.

RESULTS

Muscular Dnaja3 heterozygosity resulted in impaired locomotor activity (P < 0.05), reduced muscular cross-sectional area (P < 0.0001), and up-regulation of lipogenesis (ACC2) and pro-inflammation (STAT3) in skeletal muscles (P < 0.05). Primary myoblasts from the HSA-Dnaja3f/+ mice displayed impaired mitochondrial respiration (P < 0.01) and imbalanced mitochondrial ROS levels. A systemic proteomic analysis of the purified mitochondria from the primary myoblasts was conducted to show the abnormalities in mitochondrial function and fatty acid metabolism (P < 0.0001). At age of 13 to 14 months, the HSA-Dnaja3f/+ mice displayed increased body fat mass (P < 0.001), reduced fat-free mass (P < 0.01), and impaired glucose and insulin tolerance (P < 0.01). The short-term GMI treatment improved locomotor activity (P < 0.01) and down-regulated the protein levels of STAT3 (P < 0.05), ACC2, and mitochondrial respiratory complex III (UQCRC2) (P < 0.01) via DNAJA3 activation. The long-term GMI treatment ameliorated fat mass accumulation, glucose intolerance, and systemic inflammation (AST) (P < 0.05) in skeletal muscle, while enhancing thermogenesis (UCP1) (P < 0.01) in eWAT. GMI treatment promoted myogenesis, enhanced oxygen consumption, and ameliorated STAT3 (P < 0.01) through DNAJA3 activation (P < 0.05) in vitro.

CONCLUSIONS

Muscular Dnaja3 haploinsufficiency dysregulates mitochondrial function and lipid metabolism then leads to sarcopenic obesity. GMI emerges as a therapeutic regimen for sarcopenic obesity treatment through DNAJA3 activation.

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.

1-Monopalmitin promotes lung cancer cells apoptosis through PI3K/Akt pathway in vitro

Lung cancer is the leading cause of cancer-related death worldwide and non-small cell lung cancer (NSCLC) represents 85%. Mougeotia nummuloides and Spirulina major have been reported to possess anticancer properties. 1-Monopalmitin (1-Mono) is the principle active constituent in these natural plants. It is debating whether 1-Mono exerts antitumor effects. Therefore, we explored the role of 1-Mono in lung cancer in vitro. Results showed that 1-Mono significantly inhibited A549 and SPC-A1 cell proliferation, induced G2/M arrest and caspase-dependent apoptosis. Moreover, it suppressed the protein expression of inhibitors of apoptosis proteins (IAPs). It was further demonstrated that 1-Mono activated the PI3K/Akt pathway, suppression of PI3K/Akt activities with LY294002 and Wortmannin partially attenuated 1-Mono-mediated anticancer activities, indicating that 1-Mono-induced antitumor effects is dependent on PI3K/Akt pathway. 1-Mono induced cytoprotective autophagy since autophagy inhibitor Chloroquine dramatically enhanced 1-Mono-induced cytotoxicity. In summary, our results showed 1-Mono kills lung cancer through PI3K/Akt pathway, providing novel options for lung cancer administration.

β-catenin inhibitor ICG-001 suppress cell cycle progression and induce autophagy in endometrial cancer cells

The incidence of endometrial cancer has been rising in recent years. Gene mutation and high protein expression of β-catenin are commonly detected in endometrioid endometrial cancer. ICG-001 is a β-catenin inhibitor via blocking the complex formation of β-catenin and cAMP response element-binding protein (CREB)-binding protein (CBP). This study aims to investigate the effect of ICG-001 on endometrial cancer inhibition. First, endometrial carcinoma patient-derived xenograft (PDX)-derived organoids and primary cells were used to verify the inhibiting ability of ICG-001 on endometrial cancer. Furthermore, endometrial cancer cell lines were used to investigate the anticancer mechanism of ICG-001. Using MTT assay and tumor spheroid formation assay, ICG-001 significantly reduced the cell viability of HEC-59 and HEC-1A cells. ICG-001 enhanced cisplatin-mediated cytotoxicity. ICG-001 decreased cancer stem cell sphere formation. ICG-001 decreased the protein expressions of CD44, hexokinase 2 (HK2), and cyclin A. ICG-001 lowered the cell cycle progression by flow cytometer analysis. Autophagy, but no apoptosis, was activated by ICG-001 in endometrial cancer cells. Autophagy inhibition by ATG5 silencing enhanced ICG-001-mediated suppression of cell viability, tumor spheroid formation, and protein expression of cyclin A and CD44. This study clarified the mechanism and revealed the clinical potential of ICG-001 against endometrial cancer.

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.

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.

Suppression of PI3K/Akt/mTOR/c-Myc/mtp53 Positive Feedback Loop Induces Cell Cycle Arrest by Dual PI3K/mTOR Inhibitor PQR309 in Endometrial Cancer Cell Lines

Gene mutations in PIK3CA, PIK3R1, KRAS, PTEN, and PPP2R1A commonly detected in type I endometrial cancer lead to PI3K/Akt/mTOR pathway activation. Bimiralisib (PQR309), an orally bioavailable selective dual inhibitor of PI3K and mTOR, has been studied in preclinical models and clinical trials. The aim of this study is to evaluate the anticancer effect of PQR309 on endometrial cancer cells. PQR309 decreased cell viability in two-dimensional and three-dimensional cell culture models. PQR309 induced G1 cell cycle arrest and little cell death in endometrial cancer cell lines. It decreased CDK6 expression and increased p27 expression. Using the Proteome Profiler Human XL Oncology Array and Western blot assay, the dual inhibitor could inhibit the expressions of c-Myc and mtp53. KJ-Pyr-9, a c-Myc inhibitor, was used to prove the role of c-Myc in endometrial cancer survival and regulating the expression of mtp53. Knockdown of mtp53 lowered cell proliferation, Akt/mTOR pathway activity, and the expressions of c-Myc. mtp53 silence enhanced PQR309-inhibited cell viability, spheroid formation, and the expressions of p-Akt, c-Myc, and CDK6. This is the first study to reveal the novel finding of the PI3K/mTOR dual inhibitor in lowering cell viability by abolishing the PI3K/Akt/mTOR/c-Myc/mtp53 positive feedback loop in endometrial cancer cell lines.

Ganoderma microsporum immunomodulatory protein, GMI, promotes C2C12 myoblast differentiation in vitro via upregulation of Tid1 and STAT3 acetylation

Ageing and chronic diseases lead to muscle loss and impair the regeneration of skeletal muscle. Thus, it’s crucial to seek for effective intervention to improve the muscle regeneration. Tid1, a mitochondrial co-chaperone, is important to maintain mitochondrial membrane potential and ATP synthesis. Previously, we demonstrated that mice with skeletal muscular specific Tid1 deficiency displayed muscular dystrophy and postnatal lethality. Tid1 can interact with STAT3 protein, which also plays an important role during myogenesis. In this study, we used GMI, immunomodulatory protein of Ganoderma microsporum, as an inducer in C2C12 myoblast differentiation. We observed that GMI pretreatment promoted the myogenic differentiation of C2C12 myoblasts. We also showed that the upregulation of mitochondria protein Tid1 with the GMI pre-treatment promoted myogenic differentiation ability of C2C12 cells. Strikingly, we observed the concomitant elevation of STAT3 acetylation (Ac-STAT3) during C2C12 myogenesis. Our study suggests that GMI promotes the myogenic differentiation through the activation of Tid1 and Ac-STAT3.

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.

CD133 inhibition via autophagic degradation in pemetrexed-resistant lung cancer cells by GMI, a fungal immunomodulatory protein from Ganoderma microsporum

Background

Adaptive drug resistance is an unfavourable prognostic factor in cancer therapy. Pemetrexed-resistant lung cancer cells possess high-metastatic ability via ERK–ZEB1 pathway-activated epithelial–mesenchymal transition. GMI is a fungal immunomodulatory protein that suppresses the survival of several cancer cells.

Methods

Cell viability was analysed by MTT, clonogenic, tumour spheroid, and cancer stem cell sphere assays. Western blot assay was performed to detect the protein expression. Chemical inhibitors and ATG5 shRNA were used to inhibit autophagy. Tumour growth was investigated using xenograft mouse model.

Results

GMI decreased the viability with short- and long-term effects and induced autophagy but not apoptosis in A549/A400 cells. GMI downregulated the expression levels of CD133, CD44, NANOG and OCT4. GMI induces the protein degradation of CD133 via autophagy. CD133 silencing decreased the survival and proliferation of A549/A400 cells. GMI suppressed the growth and CD133 expression of A549/A400 xenograft tumour.

Conclusions

This study is the first to reveal the novel function of GMI in eliciting cytotoxic effect and inhibiting CD133 expression in pemetrexed-resistant lung cancer cells via autophagy. Our finding provides evidence that CD133 is a potential target for cancer therapy.

The Application of Arsenic Trioxide in Ameliorating ABT-737 Target Therapy on Uterine Cervical Cancer Cells through Unique Pathways in Cell Death

ABT-737, a B cell lymphoma-2 (Bcl-2) family inhibitor, activates apoptosis in cancer cells. Arsenic trioxide is an apoptosis activator that impairs cancer cell survival. The aim of this study was to evaluate the effect of a combination treatment with ABT-737 and arsenic trioxide on uterine cervical cancer cells. MTT (3-(4,5-dimethylthiazol-2-yl)-25-diphenyltetrazolium bromide) assay revealed that ABT-737 and arsenic trioxide induced a synergistic effect on uterine cervical cancer cells. Arsenic trioxide enhanced ABT-737-induced apoptosis and caspase-7 activation and the ABT-737-mediated reduction of anti-apoptotic protein Mcl-1 in Caski cells. Western blot assay revealed that arsenic trioxide promoted the ABT-737-mediated reduction of CDK6 and thymidylate synthetase in Caski cells. Arsenic trioxide promoted ABT-737-inhibited mitochondrial membrane potential and ABT-737-inhibited ANT expression in Caski cells. However, ABT-737-elicited reactive oxygen species were not enhanced by arsenic trioxide. The combined treatment induced an anti-apoptosis autophagy in SiHa cells. This study is the first to demonstrate that a combination treatment with ABT-737 and arsenic trioxide induces a synergistic effect on uterine cervical cancer cells through apoptosis. Our findings provide new insights into uterine cervical cancer treatment.

Historical and current perspectives on therapeutic potential of higher basidiomycetes: an overview

Mushrooms are macroscopic fungi which can be either epigeous or hypogeous and is estimated to be 140,000 on earth, yet only 10% are known. Since ancient time, it played a diverse role in human history for mycolatry, mycophagy and as medicine in folklore and religion. Many Asian and western countries consider mushrooms as panacea for a large number of diseases and utilized for consumption as a gourmet food for its taste as well as flavor. In recent years, scientific research fraternities have confirmed that various extracts and metabolites of mushrooms used traditionally are able to treat a wide range of diseases due to their balanced modulation of multiple targets thereby providing a greater therapeutic effect or equivalent curative effect to that of modern medicine. Medicinal mushrooms especially those belonging to higher basidiomycete groups are reservoir of bioactive compounds with multiple therapeutic properties. The present review provides historical importance as well as an updated information on pharmacologically relevant higher basidiomycetes belong to the genus Agaricus, Auricularia, Phellinus, Ganoderma, Pleurotus, Trametes and Lentinus and their biologically active secondary metabolites. This will help the researchers to understand various type of secondary metabolites, their therapeutic role and related in vivo or in vitro work at a glance. The mounting evidences from several scientific community across the globe, regarding various therapeutic applications of mushroom extracts, unarguably make it an advance research area worth mass attention.

Anti-inflammatory and Neuroprotective Effects of Fungal Immunomodulatory Protein Involving Microglial Inhibition

Microglia polarization of classical activation state is crucial to the induction of neuroinflammation, and has been implicated in the pathogenesis of numerous neurodegenerative diseases. Fungal immunomodulatory proteins are emerging health-promoting natural substances with multiple pharmacological activities, including immunomodulation. Herein, we investigated the anti-inflammatory and neuroprotective potential of fungal immunomodulatory protein extracted from Ganoderma microsporum (GMI) in an in vitro rodent model of primary cultures. Using primary neuron/glia cultures consisting of neurons, astrocytes, and microglia, a GMI showed an alleviating effect on lipopolysaccharide (LPS)/interferon-γ (IFN-γ)-induced inflammatory mediator production and neuronal cell death. The events of neuroprotection caused by GMI were accompanied by the suppression of Nitric Oxide (NO), Tumor Necrosis Factor-α (TNF-α), Interleukin-1β (IL-1β), and Prostaglandin E2 (PGE2) production, along with the inhibition of microglia activation. Mechanistic studies showed that the suppression of microglia pro-inflammatory polarization by GMI was accompanied by the resolution of oxidative stress, the preservation of protein tyrosine phosphatase and serine/threonine phosphatase activity, and the reduction of NF-κB, AP-1, cyclic AMP response element-binding protein (CREB), along with signal transducers and activators of transcription (Stat1) transcriptional activities and associated upstream activators. These findings suggest that GMI may have considerable potential towards the treatment of neuroinflammation-mediated neurodegenerative diseases.