GMI, an Immunomodulatory Protein from Ganoderma microsporum, Potentiates Cisplatin-Induced Apoptosis via Autophagy 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.

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 fungal immunomodulatory protein, ameliorates SARS-CoV-2 envelope protein-induced inflammation in macrophages via inhibition of MAPK pathway

Clinically, COVID-19 is often accompanied by a severe immune response (cytokine storm) which produces a large number of cytokines, such as TNF-α, IL-6 and IL-12, and consequently causes acute respiratory distress syndrome (ARDS). GMI is a type of fungal immunomodulatory protein that is cloned from Ganoderma microsporum and acts as modulating immunocyte for various inflammatory diseases. This study identifies GMI as a potential anti-inflammatory agent and determines the effects of GMI on the inhibition of SARS-CoV-2-induced cytokine secretion. Functional studies showed that SARS-CoV-2 envelop (E) protein induces inflammatory process in murine macrophages RAW264.7 and MH-S cells and in phorbol 12-myristate 13-acetate (PMA)-stimulated human THP-1 cells. GMI exhibits a strong inhibitory effect for SARS-CoV-2-E-induced pro-inflammatory mediators, including NO, TNF-α, IL-6, and IL-12 in macrophages. GMI reduces SARS-CoV-2-E-induced intracellular inflammatory molecules, such as iNOS and COX-2, and inhibits SARS-CoV-2-E-stimulated phosphorylation of ERK1/2 and P38. GMI also downregulates pro-inflammatory cytokine levels in lung tissue and serum after the mice inhale SARS-CoV-2-E protein. In conclusion, this study shows that GMI acts as an agent to alleviate SARS-CoV-2-E-induced inflammation.

The Phytochemistry of Ganoderma Species and their Medicinal Potentials

The Ganoderma genus is known for its diverse use as a functional food and therapeutic agent. This fungus has over 428 species, with Ganoderma lucidum being the most studied. The Ganoderma species produce several secondary metabolites and bioactive compounds like polysaccharides, phenols, and triterpenes, which are largely responsible for their therapeutic properties. Throughout this review, several extracts obtained from Ganoderma species have been studied to delve into their therapeutic characteristics and mechanisms. Such properties like immunomodulation, antiaging, antimicrobial, and anticancer activities have been demonstrated by several Ganoderma species and are supported by a large body of evidence. Although its phytochemicals play a vital role in its therapeutic properties, identifying the therapeutic potentials of fungal-secreted metabolites for human health-promoting benefits is a challenging task. Identification of novel compounds with distinct chemical scaffolds and their mechanism of action could help suppress the spread of rising pathogens. Thus, this review provides an updated and comprehensive overview of the bioactive components in different Ganoderma species and the underlying physiological mechanisms.

Nephroprotective Effects of Two Ganoderma Species Methanolic Extracts in an In Vitro Model of Cisplatin Induced Tubulotoxicity

Although cisplatin is used as a first-line therapy in many cancers, its nephrotoxicity remains a real problem. Acute kidney injuries induced by cisplatin can cause proximal tubular necrosis, possibly leading to interstitial fibrosis, chronic dysfunction, and finally to a cessation of chemotherapy. There are only a few nephroprotective actions that can help reduce cisplatin nephrotoxicity. This study aims to identify new prophylactic properties with respect to medicinal mushrooms. Among five Ganoderma species, the methanolic extracts of Ganoderma tuberculosum Murill., Ganoderma parvigibbosum Welti & Courtec. (10 µg/mL), and their association (5 + 5 µg/mL) were selected to study respective in vitro effects on human proximal tubular cells (HK-2) intoxicated by cisplatin. Measurements were performed after a pretreatment of 1 h with the extracts before adding cisplatin (20 µM). A viability assay, antioxidant activity, intracytoplasmic β-catenin, calcium, caspase-3, p53, cytochrome C, IL-6, NFκB, membranous KIM-1, and ROS overproduction were studied. Tests showed that both methanolic extracts and their association prevented a loss of viability, apoptosis, and its signaling pathway. G. parvigibbosum and the association prevented an increase in intracytoplasmic β-catenin. G. parvigibbosum prevented ROS overproduction and exhibited scavenger activity. None of the extracts could interfere with pro-inflammatory markers or calcium homeostasis. Our in vitro data demonstrate that these mushroom extracts have interesting nephroprotective properties. Finally, the chemical content was investigated through a phytochemical screening, and the determination of the total phenolic and triterpenoid content. Further studies about the chemical composition need to be conducted.

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.

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.

Circ-PKD2 promotes Atg13-mediated autophagy by inhibiting miR-646 to increase the sensitivity of cisplatin in oral squamous cell carcinomas

Autophagy is an evolutionally conserved catabolic process that degrades cells to maintain homeostasis. Cisplatin-activated autophagy promotes the expression of circ-PKD2, which plays a role as a tumor suppressor gene in the proliferation, migration, and invasion in oral squamous cell carcinoma (OSCC). However, the role of circ-PKD2 in regulating the sensitivity of OSCC patients to cisplatin remains to be elucidated. Overexpression of circ-PKD2 increased the formation of autophagosomes in OSCC cells and activation of proteins, such as LC3 II/I. Its activation effect on autophagy was, however, alleviated by 3-MA. Bioinformatics analyses and double luciferases reporter assays conducted in this study confirmed the existence of targeted relationships between circ-PKD2 and miR-646 and miR-646 and Atg13. Functional experiments further revealed that miR-646 reversed the autophagy and apoptosis effects of circ-PKD2 in OSCC cells treated with cisplatin. In addition, circ-PKD2 promoted the expression of ATG13 by adsorption of miR-646. Its interference with Atg13 alleviated the activation effects of circ-PKD2 on autophagy and apoptosis of miR-646. Notably, the in vivo animal experiments also confirmed that circ-PKD2 inhibited tumor proliferation and activated autophagy in OSCC cells. This study provides a theoretical basis for using circ-PKD2 as a target to regulate the sensitivity of OSCC patients to cisplatin, thus increasing its chemotherapeutic effects.

The first copper(I) complex of anthrahydrazone with potential ROS scavenging activity showed significant in vitro anticancer activity by inducing apoptosis and autophagy

Based on the anticancer pharmacophore of anthrahydrazone and quinoline, a new quinolylanthrahydrazone ligand, 9-AQH (anthracene-9-quinolylhydrazone), was synthesized to further afford four metal complexes, [Co^II(9-AQH)(NO₃)₂(H₂O)] (1), [Ni^II(9-AQH)₂(H₂O)₂]·2NO₃ (2), [Cu^I(9-AQH)₂]·NO₃ (3), [Zn^II(9-AQH)₂(NO₃)]·NO₃ (4), determined by X-ray single crystal diffraction analysis. The reaction of Cu(NO₃)₂ with 9-AQH formed the stable and repeatable copper(I) complex 3. In vitro screening demonstrated only 3 showed significant and broad-spectrum anticancer activity, indicating that Cu(I) played a key role in exerting the anticancer activity. In solution, Cu(I) was not naturally oxidized to Cu(II) suggested by ¹H-NMR (Nuclear Magnetic Resonance) and EPR (Electron Paramagnetic Resonance) analysis. The presence of 3 could also catalyze the H₂O₂ system to give hydroxyl free radicals, suggested by further EPR and electrophoresis assay. At the cellular level, although no obvious Cu(II) signals were detected and the total ROS (Reactive Oxygen Species) scavenging in the tumor cells treated with 3, the potential redox property between Cu(I)/Cu(II), as a key role, should not be denied for the significant anticancer activity of 3, considering the much complicated circumstance and other reductive substances in cells. The anticancer mechanism of 3 on the most sensitive MGC-803 cells pointed to significant cell apoptosis through mitochondrial pathway, rather than cell cycle arrest. While the autophagy observed in tumor cells treated by 3 suggested its complicated anticancer mechanism, and whether there was an intrinsic correlation still needed to be further investigated.

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.

Autophagy modulating agents as chemosensitizers for cisplatin therapy in cancer

Although cisplatin is one of the most common antineoplastic drug, its successful utilisation in cancer treatment is limited by the drug resistance. Multiple attempts have been made to find potential cisplatin chemosensitisers which would overcome cancer cells resistance thus improving antineoplastic efficacy. Autophagy modulation has become an important area of interest regarding the aforementioned topic. Autophagy is a highly conservative cellular self-digestive process implicated in response to multiple environmental stressors. The high basal level of autophagy is a common phenomenon in cisplatin-resistant cancer cells which is thought to grant survival benefit. However current evidence supports the role of autophagy in either promoting or limiting carcinogenesis depending on the context. This encourages the search of substances modulating the process to alleviate cisplatin resistance. Such a strategy encompasses not only simple autophagy inhibition but also harnessing the process to induce autophagy-dependent cell death. In this paper, we briefly describe the mechanism of cisplatin resistance with a special emphasis on autophagy and we give an extensive literature review of potential substances with cisplatin chemosensitising properties related to autophagy modulation.

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.

Germacrone Induces Apoptosis as Well as Protective Autophagy in Human Prostate Cancer Cells

Background

Germacrone, a natural product isolated from the traditional Chinese medicine Rhizoma Curcuma, has been reported to exhibit antitumor activities in vitro. To further understand the antitumor mechanism of germacrone, we investigated the growth inhibitory effect of germacrone on the human prostate cancer cell lines PC-3 (androgen independent) and 22RV1 (androgen dependent).

Materials and Methods

Prostate cancer cells were cultured with different concentrations of germacrone, and cell viability was measured by MTT assay. The levels of proteins were measured by Western blotting. Cell apoptosis was assessed by flow cytometry. Images of autophagy-related protein staining were captured by fluorescence microscopy. Autophagic flux was assessed by detecting the LC3B-II level.

Results

Our results indicated that germacrone treatment significantly inhibited cell proliferation by inducing apoptosis in a dose-dependent manner, with IC50 values of 259 μM for PC-3 cells and 396.9 μM for 22RV1 cells. Germacrone-treated cells also exhibited induction of autophagy, as evidenced by elevated LC3B-II protein expression levels and punctuate patterns. Additionally, an autophagy inhibitor enhanced the growth inhibitory effect of germacrone. Moreover, the phosphorylation of Akt and mTOR was inhibited in germacrone-treated prostate cancer cells.

Conclusion

Germacrone induced apoptosis and autophagy in prostate cancer cells by inhibiting the Akt/mTOR signaling pathway. Germacrone treatment also led to the activation of protective autophagy. These findings suggest that germacrone may potentially contribute to the development of a new therapeutic agent for prostate cancer treatment.

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 Antiproliferation Activity of Ganoderma formosanum Extracts on Prostate Cancer Cells

Androgen-independent prostate cancer accounts for mortality in the world. In this study, various extracts of a medical fungus dubbed Ganoderma formosanum were screened for inhibition of DU145 cells, an androgen-independent prostate cancer cell line. Results demonstrated that both hexane (GF-EH) and butanol (GF-EB) fraction of G. formosanum ethanol extract inhibited DU145 cell viability in a dose-dependent manner. GF-EH induced cell-cycle arrest in G1 phase of DU145 cells via downregulation of cyclin E2 protein expression. In addition, GF-EB triggered extrinsic apoptosis of DU145 cells by activating caspase 3 gene expression resulting in programed cell death. Above all, both GF-EH and GF-EB show lower toxicity to normal human fibroblast cell line compared to DU145 cell, implying that they possess specific drug action on cancer cells. This study provides a molecular basis of G. formosanum extract as a potential ingredient for treatment of androgen-independent prostate cancer.

Natural Bioactive Compounds from Fungi as Potential Candidates for Protease Inhibitors and Immunomodulators to Apply for Coronaviruses

The inhibition of viral protease is an important target in antiviral drug discovery and development. To date, protease inhibitor drugs, especially HIV-1 protease inhibitors, have been available for human clinical use in the treatment of coronaviruses. However, these drugs can have adverse side effects and they can become ineffective due to eventual drug resistance. Thus, the search for natural bioactive compounds that were obtained from bio-resources that exert inhibitory capabilities against HIV-1 protease activity is of great interest. Fungi are a source of natural bioactive compounds that offer therapeutic potential in the prevention of viral diseases and for the improvement of human immunomodulation. Here, we made a brief review of the current findings on fungi as producers of protease inhibitors and studies on the relevant candidate fungal bioactive compounds that can offer immunomodulatory activities as potential therapeutic agents of coronaviruses in the future.

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.

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.

Inhibition of proliferation and migration of melanoma cells by ketoconazole and Ganoderma immunomodulatory proteins

Ketoconazole, an antifungal agent, has been used to inhibit hormone synthesis in types of prostate and breast cancer. Immunomodulatory proteins of Ganoderma microsporum (GMI) inhibit the tumor necrosis factor-α- and epidermal growth factor-induced metastatic ability of lung cancer cells. Cutaneous malignant melanoma is a highly invasive and metastatic skin cancer. However, to the best of our knowledge, there is limited understanding regarding the effects of ketoconazole and GMI on melanoma. The current study aimed to investigate the inhibitory effects of GMI combined with ketoconazole on melanoma survival and metastasis. The effects of GMI combined with ketoconazole on the viability, migration and protein expression of melanoma cells were determined by MTT assay, Boyden chamber assay and western blot analysis, respectively. The expression of monocyte chemoattractant protein-1 (MCP-1) was investigated by enzyme-linked immunoabsorbent assay. The present results indicate that ketoconazole enhances the GMI-induced decrease in proliferation and migration of A375.S2 melanoma cells in a concentration-dependent manner. Ketoconazole was identified to reduce the level of GMI-induced phosphorylated-adenosine monophosphate-activated protein kinase (p-AMPK)-α and autophagy; however, ketoconazole did not affect p-AMPK-β levels in A375.S2 cells. In addition, ketoconazole and dorsomorphin dihydrochloride, an AMPK inhibitor, were revealed to reduce MCP-1 secretion in A375.S2 cells. In summary, the present study revealed that ketoconazole enhances GMI-inhibited proliferation and migration of A375.S2 melanoma cancer cells, and inhibits the secretion of MCP-1.

The Effect of Ganoderma Microsporum immunomodulatory proteins on alleviating PM2.5-induced inflammatory responses in pregnant rats and fine particulate matter-induced neurological damage in the offsprings

Fine particulate matter 2.5 (PM_2.5) induces free radicals and oxidative stress in animals, leading to a range of illnesses. In this study, Ganoderma Microsporum immunomodulatory (GMI) proteins were administered to alleviate PM_2.5-induced inflammatory responses in mother rats, and PM_2.5-induced inflammatory responses and neurological damage in their offspring. The results suggested that GMI administration decreased the risk of neurological disorders in mother rats and their offspring by reducing the white blood cell count, lessening inflammatory responses and PM_2.5-induced memory impairment, and preventing dendritic branches in the hippocampi from declining and microRNAs from PM_2.5-induced modulation.

Ganoderma immunomodulatory protein and chidamide down-regulate integrin-related signaling pathway result in migration inhibition and apoptosis induction

BACKGROUND

In terms of melanoma, recent advances have been made in target therapies and immune checkpoint inhibitors, but durable remission is rare. Ganoderma immunomodulatory proteins (GMI) induce a cytotoxic effect in cancer cells via autophagy. However, the role of GMI in melanoma is not clear.

PURPOSE

The aims of this study are to investigate the inhibiting effects of GMI combined with chidamide on survival and metastases of melanoma cells via integrin-related signaling pathway and to propose strategies for combining GMI and chidamide using animal model.

METHODS

Cell viability was measured by cell CCK-8. The activities of apoptosis- and migration-related proteins were detected on Western blot. Flow cytometry was used to analyze cell cycle distribution and sub-G1 fraction in treated melanoma cells. To evaluate the activity of combination GMI and chidamide treatment, an in vivo anti-tumor metastasis study was performed.

RESULTS

GMI combined with chidamide additively induced apoptosis. GMI inhibited the expressions of Integrin α5, αV, β1, and β3. The level of p-FAK was inhibited by GMI. Combination treatment of GMI and chidamide decreased survivin and increased cleaved caspase-7 and LC3 II/I. Integrin-αV overexpression activated p-FAK pathways in A375.S2 cells. GMI significantly inhibited cell growth and migration of A375.S2 cells on wound healing assay. In vivo, GMI combined with chidamide suppressed distal tumor metastasis.

CONCLUSION

GMI inhibits the migration and growth of melanoma cells via integrin-related signaling pathway. GMI and chidamide induces apoptosis. In vivo, GMI and chidamide additively reduce distant metastases. GMI and chidamide are potential immunotherapeutic adjuvant for metastatic melanoma.

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.

MicroRNA-125b Interacts with Foxp3 to Induce Autophagy in Thyroid Cancer

Thyroid cancer is rapidly increasing in incidence worldwide. Although most thyroid cancer can be cured with surgery, radioactive iodine, and/or chemotherapy, thyroid cancers still recur and may become chemoresistant. Autophagy is a complex self-degradative process that plays a dual role in cancer development and progression. In this study, we found that miR-125b was downregulated in tissue samples of thyroid cancer as well as in thyroid cancer cell lines, and the expression of Foxp3 was upregulated. Further, we demonstrated that miR-125b could directly act on Foxp3 by binding to its 3' UTR and inhibit the expression of Foxp3. A negative relationship between miR-125b and Foxp3 was thus revealed. Overexpression of miR-125b markedly sensitized thyroid cancer cells to cisplatin treatment by inducing autophagy through an Atg7 pathway in vitro and in vivo. Taken together, our findings demonstrate a novel mechanism by which miR-125b has the potential to negatively regulate Foxp3 to promote autophagy and enhance the efficacy of cisplatin in thyroid cancer. miR-125 may be of therapeutic significance in thyroid cancer.

Mechanisms of autophagy and relevant small-molecule compounds for targeted cancer therapy

Autophagy is an evolutionarily conserved, multi-step lysosomal degradation process for the clearance of damaged or superfluous proteins and organelles. Accumulating studies have recently revealed that autophagy is closely related to a variety of types of cancer; however, elucidation of its Janus role of either tumor-suppressive or tumor-promoting still remains to be discovered. In this review, we focus on summarizing the context-dependent role of autophagy and its complicated molecular mechanisms in different types of cancer. Moreover, we discuss a series of small-molecule compounds targeting autophagy-related proteins or the autophagic process for potential cancer therapy. Taken together, these findings would shed new light on exploiting the intricate mechanisms of autophagy and relevant small-molecule compounds as potential anti-cancer drugs to improve targeted cancer therapy.

NTF3 Is a Novel Target Gene of the Transcription Factor POU3F2 and Is Required for Neuronal Differentiation

POU-homeodomain transcription factor POU3F2 is a critical transcription factor that participates in neuronal differentiation. However, little is known about its downstream mediators. Here genome-wide analyses of a human neuronal differentiation cell model, NT2D1, suggested neurotrophin-3 (NTF3), a key mediator of neuronal development during the early neurogenic period, as a putative regulatory target of POU3F2. Western blot, cDNA microarray, and real-time quantitative PCR analyses showed that POU3F2 and NTF3 were upregulated during neuronal differentiation. Next-generation-sequence-based POU3F2 chromatin immunoprecipitation-sequencing and genome-wide in silico prediction demonstrated that POU3F2 binds to the NTF3 promoter during neuronal differentiation. Furthermore, unidirectional deletion or mutation of the binding site of POU3F2 in the NTF3 promoter decreased promoter-driven luciferase activity, indicating that POU3F2 is a positive regulator of NTF3 promoter activity. While NTF3 knockdown resulted in decreased viability and differentiation of NT2D1 cells, and POU3F2 knockdown downregulated NTF3 expression, recombinant NTF3 significantly rescued viable neuronal cells from NTF3- or POU3F2-knockdown cell cultures. Moreover, immunostaining showed colocalization of POU3F2 and NTF3 in developing mouse neurons. Thus, our data suggest that NTF3 is a novel target gene of POU3F2 and that the POU3F2/NTF3 pathway plays a role in the process of neuronal differentiation.

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.

Andrographolide enhances cisplatin-mediated anticancer effects in lung cancer cells through blockade of autophagy

Lung cancer is the most common cause of cancer-related death worldwide and the platinum-based drugs such as cisplatin have been used as the first line of the treatment. However, the clinical effectiveness of such chemotherapy is limited by intrinsic or acquired resistance. In this study, we found that cisplatin induced autophagy that attenuated the sensitivity of both A549 and Lewis lung cancer (LLC) cells to cisplatin. In contrast, the clinical drug andrographolide (Andro) suppressed autophagy and enhanced cisplatin-mediated apoptosis in these cells. Using two murine lung cancer models, including a subcutaneously inoculated LLC model and an orthotopic LLC implantation model, we investigated the therapeutic efficacy of the combined treatment of cisplatin and Andro. Compared with the sole cisplatin treatment, combining cisplatin with Andro potentially inhibited tumor growth, reduced the incidence of lung metastases, and relieved renal tubular damage. Moreover, the combined treatment prolonged the life span of tumor-bearing mice. TUNEL and immunohistochemistry assays showed the increase in apoptotic cells and the decrease in both conversion of LC3B-I to LC3B-II and Atg5 protein expression in the tumor tissues from mice with the combined treatment. These results suggest that Andro offers an ideal candidate of autophagy inhibitors in clinical application, and combination of cisplatin with Andro could be a promising strategy for the treatment of lung cancer.

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.

Apoptosis induction of colorectal cancer cells HTL-9 in vitro by the transformed products of soybean isoflavones by Ganoderma lucidum

Soybean isoflavones have been one of the potential preventive candidates for antitumor research in recent years. In this paper, we first studied the transformation of soybean isoflavones with the homogenized slurry of Ganoderma lucidum. The resultant transformed products (TSI) contained (703.21±4.35) mg/g of genistein, with transformed rates of 96.63% and 87.82% of daidzein and genistein, respectively, and TSI also could enrich the bioactive metabolites of G. lucidum. The antitumor effects of TSI on human colorectal cancer cell line HTL-9, human breast cancer cell line MCF-7, and human immortalized gastric epithelial cell line GES-1 were also studied. The 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) assay showed that TSI could dramatically reduce the viability rates of HTL-9 cells and MCF-7 cells without detectable cytotoxicity on GES-1 normal cells when the TSI concentration was lower than 100 μg/ml. With 100 μg/ml of TSI, HTL-9 cells were arrested in the G1 phase, and late-apoptosis was primarily induced, accompanied with partial early-apoptosis. TSI could induce primarily early-apoptosis by arresting cells in the G1 phase of MCF-7 cells. For HTL-9 cells, Western-blot and reverse-transcriptase polymerase chain reaction (RT-PCR) analysis showed that TSI (100 μg/ml) can up-regulate the expression of Bax, Caspase-3, Caspase-8, and cytochrome c (Cyto-c), indicating that TSI could induce cell apoptosis mainly through the mitochondrial pathway. In addition, the expression of p53 was up-regulated, while the expression of Survivin and nuclear factor κB (NF-κB) was down-regulated. All these results showed that TSI could induce apoptosis of HTL-9 cells by the regulation of multiple apoptosis-related genes.

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.

[Advances in the Research of the Regulation of Chinese Traditional Medicine Monomer and Its Derivatives on Autophagy in Non-small Cell Lung Cancer]

The high morbidity and mortality of non-small cell lung cancer (NSCLC) did influence the quality of life of tumor patients world-wide. There is an urgent need to develop new therapies that have high anti-tumor activity and low toxicity side effects. It is widely accepted that autophagy can play diverse roles in carcinogenesis, such as induces pro-death of lung cancer cells or helps the escape from cell death, making it become a proper anticancer target. It's believed that various monomers of Chinese traditional medicine closely correlates to anti-NSCLC activities, and that even could affect the acquired multiple drug resistance (MDR). Furthermore, autophagy might be the underling mechanisms which could play a role as the candidate targets of natural active compounds. Recent studies of terpenoids, alkaloid, dietary polyphenols, saponins and other active ingredients that extracted from a large variety of herbs suggest that different monomer compounds could either regulate the activity of pro-death autophagy or influence the level of protective autophagy of NSCLC cells, thus changing their drug sensitivity and cell viability. This paper aims to give a systemic description of the latest advances about natural compounds and their derivatives that involved in tumorigenesis of NSCLC via inducing the autophagy.

Antioxidant activities of ginsenoside Rg1 against cisplatin-induced hepatic injury through Nrf2 signaling pathway in mice

Oxidative stress is mainly caused by reactive oxygen species (ROS). The damage causes a net stress on normal organs, leading to a gradual loss of vital physiological function. ROS, such as free radicals, represent a class of molecules which are derived from the metabolism of oxygen and exist inherently. However, excessive produced ROS can damage all aerobic organisms. Ginseng is one of the most commonly used alternative herbal medicines, also as a traditional Chinese medicine. The aim of this study is to investigate the antioxidant potential function of ginsenoside Rg1 against cisplatin-caused hepatic damage. Male mice were treated with cisplatin to induce oxidative stress to mimic the side effect of anti-cancer drug cisplatin. Ginsenoside Rg1 effectively prevented against cisplatin-induced hepatotoxicity, alleviating histological lesions. Antioxidant functions of Rg1 were restrained by the activation of p62-Keap1-Nrf2 signaling pathway, simultaneously accompanied with expression of protein products. Accumulative p62 and increased activation of JNK in hepatocytes promoted the activation of Nrf2. For the other, degradation of Nrf2 was guided by tyrosine phosphorylation, ubiquitin, and Keap1. In summary, Rg1 prevents hepatotoxicity mainly by inhibiting the binding of Keap1 and Nrf2, partly by p62 accumulation, and more importantly by increasing the production of antioxidative proteins associated to Nrf2. Pharmacological activation of Nrf2 is an effective way in combating against liver injury.

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.

AKT/mTOR signaling pathway is involved in salvianolic acid B-induced autophagy and apoptosis in hepatocellular carcinoma cells

Chinese medicines are emerging as an attractive new generation of anticancer drugs. Here, we explored the impact of salvianolic acid B (Sal B), the major water-soluble compounds of Danshen, on apoptosis and autophagy of human hepatocellular carcinoma cells (HCC). We also investigated the related molecular mechanisms. We found that Sal B exhibits potent ability to inhibit HCC cells viability in a concentration-dependent manner, and to induce apoptosis via the mitochondrial apoptosis pathway. Additionally, Sal B could also induce autophagy. Furthermore, pretreatment with the autophagy inhibitor chloroquine or 3-methyladenine showed the potential in attenuating the apoptosis rate induced by Sal B. Mechanistically, Sal B treatment inhibited the AKT/mTOR signaling cascade in vitro. Overexpression of AKT abolished the effects of Sal B on HCC cells, suggesting a critical role of the AKT/mTOR signaling pathway in Sal B-induced biological effects. Our results indicated that the mitochondrial pathway was involved in Sal B-induced apoptosis of HCC cells. Moreover, the AKT/mTOR signaling pathway was involved in Sal B-induced autophagy, which promoted apoptosis. This study may provide a promising strategy for using Sal B as a chemotherapeutic agent for patients with HCC.