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1.
J Fungi (Basel) ; 9(11)2023 Nov 06.
Article in English | MEDLINE | ID: mdl-37998890

ABSTRACT

Rhizoctonia solani is a significant pathogen affecting various crops, including tobacco. In this study, a bacterial strain, namely Y246, was isolated from the soil of healthy plants and exhibited high antifungal activity. Based on morphological identification and DNA sequencing, this bacterial strain was identified as Bacillus safensis. The aim of this investigation was to explore the antifungal potential of strain Y246, to test the antifungal stability of Y246 by adjusting different cultivation conditions, and to utilize gas chromatography-mass spectrometry (GC-MS) to predict the volatile compounds related to antifungal activity in Y246. In vitro assays demonstrated that strain Y246 exhibited a high fungal inhibition rate of 76.3%. The fermentation broth and suspension of strain Y246 inhibited the mycelial growth of R. solani by 66.59% and 63.75%, respectively. Interestingly, treatment with volatile compounds derived from the fermentation broth of strain Y246 resulted in abnormal mycelial growth of R. solani. Scanning electron microscopy analysis revealed bent and deformed mycelium structures with a rough surface. Furthermore, the stability of antifungal activity of the fermentation broth of strain Y246 was assessed. Changes in temperature, pH value, and UV irradiation time had minimal impact on the antifungal activity, indicating the stability of the antifungal activity of strain Y246. A GC-MS analysis of the volatile organic compounds (VOCs) produced by strain Y246 identified a total of 34 compounds with inhibitory effects against different fungi. Notably, the strain demonstrated broad-spectrum activity, exhibiting varying degrees of inhibition against seven pathogens (Alternaria alternata, Phomopsis. sp., Gloeosporium musarum, Dwiroopa punicae, Colletotrichum karstii, Botryosphaeria auasmontanum, and Botrytis cinerea). In our extensive experiments, strain Y246 not only exhibited strong inhibition against R. solani but also demonstrated remarkable inhibitory effects on A. alternata-induced tobacco brown spot and kiwifruit black spot, with impressive inhibition rates of 62.96% and 46.23%, respectively. Overall, these findings highlight the significant antifungal activity of B. safensis Y246 against R. solani. In addition, Y246 has an excellent antifungal stability, with an inhibition rate > 30% under different treatments (temperature, pH, UV). The results showed that the VOCs of strain Y246 had a strong inhibitory effect on the colony growth of R. solani, and the volatile substances produced by strain Y246 had an inhibitory effect on R. solani at rate of 70.19%. Based on these results, we can conclude that Y246 inhibits the normal growth of R. solani. These findings can provide valuable insights for developing sustainable agricultural strategies.

2.
Oncotarget ; 8(46): 80358-80372, 2017 Oct 06.
Article in English | MEDLINE | ID: mdl-29113309

ABSTRACT

Macrophage migration inhibitory factor (MIF) is over-expressed and secreted in various cancer cells in particular in response to hypoxia. Recent studies have shown that, under hypoxic conditions, glioblastoma (GBM) cells display the ability to drive blood-perfused vasculogenic mimicry (VM). The aim of this study was to investigate the underlying mechanism of MIF in the regulation of hypoxia-induced VM in GBM cells. By analyzing clinical specimens, we observed the co-localization of MIF, C-X-C motif chemokine receptor 4 (CXCR4) and VM in hypoxic regions of gliomas. In vitro, the exposure of GBM cells (U87 and U251) to hypoxia increased the expression of MIF and CXCR4 and induced VMs. Other data demonstrated that ectogenic rhMIF promoted VMs in GBM cells and knock-down endogenous MIF attenuated hypoxia-induced VMs. In addition, we demonstrated that MIF augmented VM formation ability by enhancing the epithelial mesenchymal transition (EMT) through the CXCR4-AKT pathway. Moreover, in vivo, the subcutaneous injection of rhMIF resulted in the progression of EMT and VMs formation. On the contrary, CXCR4-AKT pathway inhibitors blocked the effects of rhMIF on EMT and VMs formation. Collectively, our results support a critical role for the MIF-CXCR4 signaling axis in regulating hypoxia-induced VMs formation, indicating the potential usefulness of MIF as a notable target for the anti-vascularization treatment of GBM.

3.
Int J Oncol ; 49(5): 2105-2115, 2016 Nov.
Article in English | MEDLINE | ID: mdl-27666391

ABSTRACT

Macrophage migration inhibitory factor (MIF) is highly expressed in glioblastoma, promoting malignant progression and suppresses immune surveillance. However, the mechanism underlying its biological roles in human glioblastoma and the capability of MIF to escape dendritic cell (DC) surveillance remain poorly understood. In the present study, we found that recombinant human MIF (rhMIF) activated the RhoA­ROCK1 pathway and simultaneously upregulated F­actin fibre formation. Additionally, we showed that rhMIF increased autophagy in glioblastoma cells, and knockdown of endogenic MIF suppressed autophagy. In glioma specimens, MIF expression was significantly correlated with LC3B levels. Moreover, we confirmed that the activity of Rho­associated coiled­coil containing kinase (ROCK)1 played a crucial role in MIF­induced autophagy. Y26736, a ROCK1 inhibitor, blocked the MIF­mediated increase in migration and colony formation in glioblastoma multiforme (GBM) cells. Furthermore, exogenous rhMIF suppressed the migration of both immature DCs (iDCs) and mature DCs (mDCs). Addition of rhMIF during the maturation process of iDCs impaired the expression of co­stimulatory markers. Taken together, our results identified ROCK1 as a critical mediator of MIF­induced autophagy and the immunosuppressive effect of MIF on DC surveillance in glioblastoma.


Subject(s)
Autophagy , Dendritic Cells/immunology , Gene Expression Regulation, Neoplastic , Glioblastoma/immunology , Intramolecular Oxidoreductases/metabolism , Macrophage Migration-Inhibitory Factors/metabolism , rho-Associated Kinases/metabolism , Blotting, Western , Dendritic Cells/metabolism , Dendritic Cells/pathology , Glioblastoma/metabolism , Glioblastoma/pathology , Humans , Immunoenzyme Techniques , Intramolecular Oxidoreductases/genetics , Macrophage Migration-Inhibitory Factors/genetics , Real-Time Polymerase Chain Reaction , Reverse Transcriptase Polymerase Chain Reaction , Tumor Cells, Cultured , rho-Associated Kinases/genetics
4.
Oncotarget ; 7(49): 80521-80542, 2016 Dec 06.
Article in English | MEDLINE | ID: mdl-27602954

ABSTRACT

Tumor-associated macrophages (TAMs) are enriched in gliomas and help create a tumor-immunosuppressive microenvironment. A distinct M2-skewed type of macrophages makes up the majority of glioma TAMs, and these cells exhibit pro-tumor functions. Gliomas contain large hypoxic areas, and the presence of a correlation between the density of M2-polarized TAMs and hypoxic areas suggests that hypoxia plays a supportive role during TAM recruitment and induction. Here, we investigated the effects of hypoxia on human macrophage recruitment and M2 polarization. We also investigated the influence of the HIF inhibitor acriflavine (ACF) on M2 TAM infiltration and tumor progression in vivo. We found that hypoxia increased periostin (POSTN) expression in glioma cells and promoted the recruitment of macrophages. Hypoxia-inducible POSTN expression was increased by TGF-α via the RTK/PI3K pathway, and this effect was blocked by treating hypoxic cells with ACF. We also demonstrated that both a hypoxic environment and hypoxia-treated glioma cell supernatants were capable of polarizing macrophages toward a M2 phenotype. ACF partially reversed the M2 polarization of macrophages by inhibiting the upregulation of M-CSFR in macrophages and TGF-ß in glioma cells under hypoxic conditions. Administering ACF also ablated tumor progression in vivo. Our findings reveal a mechanism that underlies hypoxia-induced TAM enrichment and M2 polarization and suggest that pharmacologically inhibiting HIFs may reduce M2-polarized TAM infiltration and glioma progression.


Subject(s)
Brain Neoplasms/metabolism , Cell Adhesion Molecules/metabolism , Cell Plasticity , Chemotaxis , Glioma/metabolism , Macrophages/metabolism , Receptors, Granulocyte-Macrophage Colony-Stimulating Factor/metabolism , Transforming Growth Factor beta/metabolism , Tumor Hypoxia , Tumor Microenvironment , Acriflavine/pharmacology , Animals , Antineoplastic Agents/pharmacology , Brain Neoplasms/drug therapy , Brain Neoplasms/genetics , Brain Neoplasms/pathology , Cell Adhesion Molecules/genetics , Cell Communication , Cell Proliferation , Cytokines/metabolism , ErbB Receptors/metabolism , Glioma/drug therapy , Glioma/genetics , Glioma/pathology , Humans , Hypoxia-Inducible Factor 1, alpha Subunit/antagonists & inhibitors , Hypoxia-Inducible Factor 1, alpha Subunit/genetics , Hypoxia-Inducible Factor 1, alpha Subunit/metabolism , Macrophages/drug effects , Macrophages/pathology , Male , Mice, Inbred BALB C , Mice, Nude , Phosphatidylinositol 3-Kinase/metabolism , RNA Interference , Signal Transduction , THP-1 Cells , Time Factors , Transfection , Transforming Growth Factor alpha/metabolism , Tumor Burden , Up-Regulation
5.
World Neurosurg ; 96: 612.e1-612.e7, 2016 Dec.
Article in English | MEDLINE | ID: mdl-27613496

ABSTRACT

BACKGROUND: Intracranial schwannomas usually arise from sensory nerves with a predilection for the trigeminal nerve and the vestibular component of the eighth cranial nerve (VIII). Schwannoma arising in the sella and extending into the suprasellar region is exceedingly rare and easily misdiagnosed as pituitary macroadenoma. Only 26 cases of intrasellar schwannomas have been reported in the literature. CASE DESCRIPTION: A patient with an intrasellar schwannoma and suprasellar extension was presurgically diagnosed as having pituitary macroadenoma. Subtotal excision of the lesion was performed via an endoscopic endonasal transsphenoidal approach. Histopathology showed schwannoma. His symptoms improved after surgery. Magnetic resonance imaging 6 months after surgery showed a remnant schwannoma in the sella. CONCLUSIONS: Although schwannoma in the sellar region is rare, it remains an important differential diagnosis because of different surgical approaches.


Subject(s)
Adenoma/diagnosis , Adenoma/surgery , Diagnostic Errors , Neurilemmoma/diagnosis , Neurilemmoma/surgery , Pituitary Neoplasms/diagnosis , Pituitary Neoplasms/surgery , Sella Turcica/surgery , Adenoma/pathology , Endoscopy , Humans , Magnetic Resonance Imaging , Male , Middle Aged , Neurilemmoma/pathology , Pituitary Neoplasms/pathology , Sella Turcica/pathology
6.
Int J Oncol ; 49(2): 519-28, 2016 Aug.
Article in English | MEDLINE | ID: mdl-27278737

ABSTRACT

Hypoxia induces protective autophagy in advanced glioblastoma cells, and targeting this process may improve the outcome for glioblastoma patients. Recent studies have suggested that the autophagic process is upregulated in glioblastoma cells in response to extensive hypoxia. Here, we describe a novel tumor suppressor in glioblastoma cells, whereby hypoxia downregulated CREBRF expression and acts as a potent inhibitor of autophagy in glioblastoma cells via the CREB3/ATG5 pathway. Our results demonstrate that CREBRF expression negatively correlates with autophagic and HIF-1α levels in different grade gliomas. Given that CREBRF is a negative regulator of CREB3, CREB3 knockdown also repressed hypoxia-induced autophagy in glioblastoma cells in vitro. Collectively, our findings provide new insight into the molecular mechanisms underlying hypoxia-induced glioblastoma cell autophagy and indicate that the hypoxia/CREBRF/CREB3/ATG5 pathway plays a central role in malignant glioma progression.


Subject(s)
Autophagy-Related Protein 5/metabolism , Brain Neoplasms/metabolism , Cell Hypoxia/physiology , Cyclic AMP Response Element-Binding Protein/metabolism , Glioblastoma/metabolism , Tumor Suppressor Proteins/metabolism , Autophagy/genetics , Autophagy/physiology , Autophagy-Related Protein 5/genetics , Brain Neoplasms/genetics , Brain Neoplasms/pathology , Cell Line, Tumor , Cyclic AMP Response Element-Binding Protein/genetics , Down-Regulation , Glioblastoma/genetics , Glioblastoma/pathology , Humans
7.
Autophagy ; 12(7): 1129-52, 2016 07 02.
Article in English | MEDLINE | ID: mdl-27163161

ABSTRACT

Hypoxia induces protective autophagy in glioblastoma cells and new therapeutic avenues that target this process may improve the outcome for glioblastoma patients. Recent studies have suggested that the autophagic process is upregulated in glioblastomas in response to extensive hypoxia. Hypoxia also induces the upregulation of a specific set of proteins and microRNAs (miRNAs) in a variety of cell types. IL6 (interleukin 6), an inflammatory autocrine and paracrine cytokine that is overexpressed in glioblastoma, has been reported to be a biomarker for poor prognosis because of its tumor-promoting effects. Here, we describe a novel tumor-promoting mechanism of IL6, whereby hypoxia-induced IL6 acts as a potent initiator of autophagy in glioblastoma via the phosphorylated (p)-STAT3-MIR155-3p pathway. IL6 and p-STAT3 levels correlated with the abundance of autophagic cells and HIF1A levels in human glioma tissues and with the grade of human glioma, whereas inhibition of exogenous or endogenous IL6 repressed autophagy in glioblastoma cells in vitro. Knockdown of endogenous MIR155-3p inhibited IL6-induced autophagy, and enforced expression of MIR155-3p restored the anti-autophagic activity of IL6 inhibitors. We show that the hypoxia-IL6-p-STAT3-MIR155-3p-CREBRF-CREB3-ATG5 pathway plays a central role in malignant glioma progression, with blockade of the IL6 receptor by tocilizumab demonstrating a certain level of therapeutic efficacy in a xenograft model in vivo, especially in combination with temozolomide. Moreover, tocilizumab inhibits autophagy by promoting tumor apoptosis. Collectively, our findings provide new insight into the molecular mechanisms underlying hypoxia-induced glioma cell autophagy and point toward a possible efficacious adjuvant therapy for glioblastoma patients.


Subject(s)
Antibodies, Monoclonal, Humanized/pharmacology , Autophagy/drug effects , Autophagy/physiology , Glioblastoma/metabolism , Interleukin-6/metabolism , Apoptosis Regulatory Proteins/drug effects , Apoptosis Regulatory Proteins/metabolism , Brain Neoplasms/pathology , Carcinogens/metabolism , Cell Hypoxia/drug effects , Cell Line, Tumor , Glioblastoma/pathology , Humans , MicroRNAs/metabolism , STAT3 Transcription Factor/metabolism , Signal Transduction , Tumor Suppressor Proteins/metabolism
8.
Oncol Rep ; 35(3): 1771-7, 2016 Mar.
Article in English | MEDLINE | ID: mdl-26750768

ABSTRACT

The present study was the first to examine the effect of microRNA-Let-7f (miR-Let-7f) inhibiting vasculogenic mimicry (VM) of human glioma cells. The postoperative survival time was significantly poor in VM-positive glioma patients compared with those without VM. Thus, it is reasonable to postulate that miR-Let-7f functions as a potent tumor suppressor by inhibiting glioma VM. However, the molecular mechanisms involved remain poorly clarified. Our preliminary studies revealed that miR-Let-7f suppressed VM by disturbing periostin (POSTN)-induced migration of glioma cells. Our results clearly demonstrated that inhibiting the pro-migratory function of POSTN by the overexpression of miR-Let-7f significantly reduced the formation of VM. Our findings suggest that miR-Let-7f may serve as a potential complementary therapeutic target in the anti­angiogenesis treatment of gliomas via suppressing VM.


Subject(s)
Cell Adhesion Molecules/genetics , Cell Movement/genetics , Glioma/genetics , MicroRNAs/genetics , Adolescent , Adult , Aged , Cell Line, Tumor , Cell Proliferation/genetics , Cell Survival , Child , Child, Preschool , Female , Genes, Tumor Suppressor , Glioma/pathology , Humans , Male , Middle Aged , Neovascularization, Pathologic/genetics , Neovascularization, Pathologic/pathology , Transfection
9.
Oncotarget ; 7(4): 4785-805, 2016 Jan 26.
Article in English | MEDLINE | ID: mdl-26715733

ABSTRACT

Here, we report that microRNA-584-3p (miR-584-3p) is up-regulated in hypoxic glioma cells and in high-grade human glioma tumors (WHO grades III-IV) relative to normoxic cells and to low-grade tumors (WHO grades I-II), respectively. The postoperative survival time was significantly prolonged in the high-grade glioma patients with high miR-584-3p expression compared with those with low miR-584-3p expression. miR-584-3p may function as a potent tumor suppressor and as a prognostic biomarker for malignant glioma. However, the molecular mechanisms underlying these properties remain poorly understood. Our mechanistic studies revealed that miR-584-3p suppressed the migration and invasion of glioma cells by disrupting hypoxia-induced stress fiber formation. Specifically, we have found that ROCK1 is a direct and functionally relevant target of miR-584-3p in glioma cells. Our results have demonstrated a tumor suppressive function of miR-584-3p in glioma, in which it inhibits the migration and invasion of tumor cells by antagonizing hypoxia-induced, ROCK1-dependent stress fiber formation. Our findings have potential implications for glioma gene therapy and suggest that miR-584-3p could represent a prognostic indicator for glioma.


Subject(s)
Biomarkers, Tumor/metabolism , Brain Neoplasms/pathology , Cell Movement , Cell Proliferation , Glioma/pathology , MicroRNAs/genetics , rho-Associated Kinases/metabolism , Adolescent , Adult , Aged , Animals , Apoptosis , Biomarkers, Tumor/genetics , Blotting, Western , Brain Neoplasms/genetics , Brain Neoplasms/metabolism , Cell Cycle , Child , Child, Preschool , Female , Follow-Up Studies , Glioma/genetics , Glioma/metabolism , Humans , Immunoenzyme Techniques , Male , Mice , Mice, Inbred BALB C , Mice, Nude , Middle Aged , Neoplasm Grading , Neoplasm Invasiveness , Prognosis , RNA, Messenger/genetics , Real-Time Polymerase Chain Reaction , Reverse Transcriptase Polymerase Chain Reaction , Survival Rate , Tumor Cells, Cultured , Xenograft Model Antitumor Assays , Young Adult , rho-Associated Kinases/genetics
10.
Oncotarget ; 6(39): 41620-37, 2015 Dec 08.
Article in English | MEDLINE | ID: mdl-26536662

ABSTRACT

Human glioblastoma multiforme (GBM) is a malignant solid tumor characterized by severe hypoxia. Autophagy plays a protective role in cancer cells under hypoxia. However, the microRNA (miRNA)-related molecular mechanisms underlying hypoxia-reduced autophagy remain poorly understood in GBM. In this study, we performed a miRNA microarray analysis on GBM cells and found that numerous miRNAs were differentially expressed under hypoxic conditions. Further research showed that miR224-3p, one of the significantly down-regulated miRNAs, was involved in regulating hypoxia-induced autophagy in GBM cells. Overexpression of miR224-3p abolished hypoxia-induced autophagy, whereas knocking down endogenous miR224-3p increased autophagic activity under normoxia. In addition, we demonstrated that miR224-3p inhibited autophagy by directly suppressing the expression of two autophagy-related genes (ATGs), ATG5 and FAK family-interacting protein of 200 kDa (FIP200). Furthermore, in vitro, miR224-3p attenuated cell proliferation and promoted hypoxia-induced apoptosis, and in vivo, overexpression of miR224-3p inhibited tumorigenesis of GBM cells. Collectively, our study identified a novel hypoxia-down-regulated miRNA, miR224-3p, as a key modulator of autophagy by inhibiting ATGs in GBM cells.


Subject(s)
Autophagy/genetics , Glioblastoma/genetics , MicroRNAs/genetics , Tumor Microenvironment , 3' Untranslated Regions , Animals , Apoptosis , Autophagy-Related Protein 5 , Autophagy-Related Proteins , Cell Hypoxia , Cell Line, Tumor , Cell Proliferation , Gene Expression Profiling/methods , Gene Expression Regulation, Neoplastic , Glioblastoma/metabolism , Glioblastoma/pathology , Heterografts , Humans , Male , Mice, Nude , MicroRNAs/metabolism , Microtubule-Associated Proteins/genetics , Microtubule-Associated Proteins/metabolism , Oligonucleotide Array Sequence Analysis , Protein Binding , Protein-Tyrosine Kinases/genetics , Protein-Tyrosine Kinases/metabolism , RNA Interference , Signal Transduction , Time Factors , Transfection , Tumor Burden
11.
Acta Crystallogr Sect E Struct Rep Online ; 67(Pt 12): m1776-7, 2011 Dec 01.
Article in English | MEDLINE | ID: mdl-22199568

ABSTRACT

The title compound, [Co(C(2)H(8)N(2))(3)](2)[SiMo(8)V(4)O(40)(VO)(2)]·6H(2)O, was prepared under hydro-thermal conditions. The asymmetric unit consists of a transition metal complex [Co(en)(3)](3+) cation (en is ethyl-enediamine), one half of an [SiMo(8)V(4)O(40)(VO)(2)](6-) heteropolyanion, two solvent water mol-ecules in general positions and two half-mol-ecules of water located on a mirror plane. In the complex cation, the Co(3+) ion is in a distorted octa-hedral coordination environment formed by six N atoms of the three chelating en ligands. One of the en ligands exhibits disorder of its aliphatic chain over two sets of sites of equal occupancy. The [SiMo(8)V(4)O(40)(VO)(2)](6-) heteropolyanion is a four-electron reduced bivanadyl-capped α-Keggin-type molybdenum-vanadium-oxide cluster. In the crystal, it is located on a mirror plane, which results in disorder of the central tetra-hedral SiO(4) group: the O atoms of this group occupy two sets of sites related by a mirror plane. Furthermore, all of the eight µ(2)-oxide groups are also disordered over two sets of sites with equal occupancy. There are extensive inter-molecular N-H⋯O hydrogen bonds between the complex cations and inorganic polyoxidoanions, leading to a three-dimensional supra-molecular network.

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