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1.
Virology ; 548: 49-58, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32838946

RESUMO

Human cytomegalovirus (HCMV) is a widespread herpesvirus that establishes latency in myeloid cells and persists by manipulating immune signaling. Chemokine receptor CXCR4 and its ligand CXCL12 regulate movement of myeloid progenitors into bone marrow and out into peripheral tissues. HCMV amplifies CXCL12-CXCR4 signaling through viral chemokine receptor US27 and cmvIL-10, a viral cytokine that binds the cellular IL-10 receptor (IL-10R), but precisely how these viral proteins influence CXCR4 is unknown. We used the proximity ligation assay (PLA) to examine association of CXCR4, IL-10R, and US27 in both transfected and HCMV-infected cells. CXCR4 and IL-10R colocalized to discrete clusters, and treatment with CXCL12 and cmvIL-10 dramatically increased receptor clustering and calcium flux. US27 was associated with CXCR4 and IL-10R in PLA clusters and further enhanced cluster formation and calcium signaling. These results indicate that CXCR4, IL-10R, and US27 form a novel virus-host signaling complex that enhances CXCL12 signaling during HCMV infection.


Assuntos
Infecções por Citomegalovirus/metabolismo , Citomegalovirus/metabolismo , Receptores CXCR4/metabolismo , Receptores de Quimiocinas/metabolismo , Receptores de Interleucina-10/metabolismo , Proteínas Virais/metabolismo , Quimiocina CXCL12/genética , Quimiocina CXCL12/metabolismo , Citomegalovirus/genética , Infecções por Citomegalovirus/genética , Infecções por Citomegalovirus/virologia , Interações Hospedeiro-Patógeno , Humanos , Ligação Proteica , Receptores CXCR4/genética , Receptores de Quimiocinas/genética , Receptores de Interleucina-10/genética , Transdução de Sinais , Proteínas Virais/genética
2.
Am J Physiol Cell Physiol ; 319(3): C579-C588, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32608990

RESUMO

Identification of specific biomarkers for ischemic stroke is necessary due to their abilities to improve treatment outcomes. Many studies have demonstrated the involvement of microRNAs (miRNAs) in the pathogenesis and complications of ischemic stroke and patient outcomes. We found that the expression of miR-874-3p was downregulated in clinical samples of ischemic stroke. Thus the present study explored the potential role of miR-874-3p in ischemic stroke and related mechanisms. A mouse model of ischemic stroke was constructed by middle cerebral artery occlusion. The relationship among miR-874-3p, C-X-C motif chemokine ligand 12 (CXCL12), and the Wnt/ß-catenin pathway was explored by dual luciferase reporter assay and Western blot analysis. Angiogenesis and brain tissue apoptosis were evaluated by immunofluorescence staining and TUNEL staining, respectively. ELISA was introduced to measure levels of inflammatory factors, including tumor necrosis factor-α (TNF-α), interleukin (IL)-1, IL-6, IL-8, and IL-10 in brain tissues. Primary hippocampal neuronal cells were isolated from the mouse model of ischemic stroke and incubated with human umbilical vein endothelial cells (HUVECs) for HUVEC tube formation. High expression of CXCL12 and low expression of miR-874-3p were confirmed in ischemic stroke. In addition, miR-874-3p was found to target and downregulate CXCL12, thus reducing TNF-α, IL-1, IL-6, and IL-8 levels, but enhancing IL-10 level. Collectively, upregulating miR-874-3p inhibits CXCL12 expression to promote angiogenesis and inhibit inflammation in ischemic stroke mice by activating the Wnt/ß-catenin pathway, which may provide a new direction of ischemic stroke treatment.


Assuntos
Quimiocina CXCL12/metabolismo , Inflamação/metabolismo , MicroRNAs/genética , Acidente Vascular Cerebral/metabolismo , Animais , Apoptose/fisiologia , Isquemia Encefálica/genética , Isquemia Encefálica/metabolismo , Camundongos , Neurônios/metabolismo , Acidente Vascular Cerebral/genética , Fator de Necrose Tumoral alfa/metabolismo , Regulação para Cima
3.
PLoS One ; 15(7): e0236622, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32730361

RESUMO

BACKGROUND: Increased attention is being paid to the relationship between the immune status of the tumor microenvironment and tumor prognosis. The application of immune scoring in evaluating the clinical prognosis of liver cancer patients has not yet been explored. This study sought to clarify the association between immune score and prognosis and construct a clinical nomogram to predict the survival of patients with liver cancer. METHODS: A total of 346 patients were included in our analysis datasets downloaded from The Cancer Genome Atlas (TCGA) dataset. A Cox proportional-hazards regression model was used to estimate the adjusted hazard ratios (HRs). A nomogram was built based on the results of multivariate analysis and was subjected to bootstrap internal validation. The predictive accuracy and discriminative ability were measured by the concordance index (C-index) and the calibration curve. Through the functional analysis of differential expression of genes with different immune scores, the target genes were screened out. RESULTS: In comparison with patients with low immune scores, those with intermediate and high immune scores had significantly improved survival time [HR and 95% confidence interval (CI): 0.54 (0.30-0.97) and 0.51 (0.27-0.97), respectively]. The C-index for survival time prediction was 0.66 (95% CI: 0.60-0.71). The calibration plot for the probability of survival at three or five years showed good agreement between prediction by the nomogram and actual observations. The top 10 hub genes were CXCL8(chemokine (C-X-C motif) ligand 8), SYK(spleen tyrosine kinase), CXCL12(chemokine (C-X-C motif) ligand 12), CXCL10 (chemokine (C-X-C motif) ligand10), CXCL1(chemokine (C-X-C motif) ligand1), CCL5(chemokine (C-C motif) ligand 5), CCL20(chemokine (C-C motif) ligand 20), LCK, CXCL11(chemokine (C-X-C motif) ligand 11), CCR5(chemokine (C-C motif) receptor 5). More importantly, we found that the high expression of CXCL8 and CXCL1 were related to the prognosis. CONCLUSIONS: High and/or intermediate immune scores are significantly correlated with better survival time in patients with liver cancer. Moreover, nomograms for predicting prognosis may help to estimate the survival of patients. We also propose that CXCL8 and CXCL1 may be a potential therapeutic target for liver cancer treatment.


Assuntos
Neoplasias Hepáticas/patologia , Nomogramas , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Quimiocina CXCL12/genética , Quimiocina CXCL12/metabolismo , Bases de Dados Factuais , Feminino , Humanos , Interleucina-8/genética , Interleucina-8/metabolismo , Estimativa de Kaplan-Meier , Neoplasias Hepáticas/imunologia , Neoplasias Hepáticas/mortalidade , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Modelos de Riscos Proporcionais , Quinase Syk/genética , Quinase Syk/metabolismo , Adulto Jovem
4.
Mol Pharmacol ; 98(2): 72-87, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32474443

RESUMO

G protein-coupled receptors (GPCRs) are biologic switches that transduce extracellular stimuli into intracellular responses in the cell. Temporally resolving GPCR transduction pathways is key to understanding how cell signaling occurs. Here, we investigate the kinetics and dynamics of the activation and early signaling steps of the CXC chemokine receptor (CXCR) 4 in response to its natural ligands CXC chemokine ligand (CXCL) 12 and macrophage migration inhibitory factor (MIF), using Förster resonance energy transfer-based approaches. We show that CXCR4 presents a multifaceted response to CXCL12, with receptor activation (≈0.6 seconds) followed by a rearrangement in the receptor/G protein complex (≈1 seconds), a slower dimer rearrangement (≈1.7 seconds), and prolonged G protein activation (≈4 seconds). In comparison, MIF distinctly modulates every step of the transduction pathway, indicating distinct activation mechanisms and reflecting the different pharmacological properties of these two ligands. Our study also indicates that CXCR4 exhibits some degree of ligand-independent activity, a relevant feature for drug development. SIGNIFICANCE STATEMENT: The CXC chemokine ligand (CXCL) 12/CXC chemokine receptor (CXCR) 4 axis represents a well-established therapeutic target for cancer treatment. We demonstrate that CXCR4 exhibits a multifaceted response that involves dynamic receptor dimer rearrangements and that is kinetically embedded between receptor-G protein complex rearrangements and G protein activation. The alternative endogenous ligand macrophage migration inhibitory factor behaves opposite to CXCL12 in each assay studied and does not lead to G protein activation. This detailed understanding of the receptor activation may aid in the development of more specific drugs against this target.


Assuntos
Quimiocina CXCL12/metabolismo , Oxirredutases Intramoleculares/metabolismo , Fatores Inibidores da Migração de Macrófagos/metabolismo , Receptores CXCR4/química , Receptores CXCR4/metabolismo , Transferência Ressonante de Energia de Fluorescência , Células HEK293 , Humanos , Cinética , Ligação Proteica , Multimerização Proteica , Transdução de Sinais
5.
Anticancer Res ; 40(6): 3221-3229, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32487616

RESUMO

BACKGROUND/AIM: Chemokines are cytokines involved not only in inflammatory but also in inappropriate response of the immune system in breast cancer (BC) progression. We examined the diagnostic usefulness of CXCL12, CXCR4 and CA 15-3 in BC patients, based on ROC curve analysis. MATERIALS AND METHODS: The study group consisted of 100 patients with BC; the control group consisted of 35 women with benign breast disease and 35 healthy patients. The median concentration of chemokines was measured by ELISA and that of CA 15-3 by chemiluminescent microparticle immunoassay. RESULTS: The concentrations of CXCL12 and CXCR4 in the BC group were significantly higher than those in the control groups. The AUC value of CXCL12 (0.7502) was the highest of all the chemokines measured in the BC patients. CONCLUSION: There may be a link between CXCL12, CXCR4 and BC that can assist in the diagnosis, markedly when combined with CA 15-3.


Assuntos
Neoplasias da Mama/genética , Quimiocina CXCL12/genética , Receptores CXCR4/genética , Biomarcadores Tumorais/genética , Neoplasias da Mama/metabolismo , Quimiocina CXCL12/metabolismo , Feminino , Humanos , Receptores CXCR4/metabolismo , Transdução de Sinais
6.
Anticancer Res ; 40(5): 2725-2737, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32366418

RESUMO

BACKGROUND/AIM: Glioblastoma (GB) is the most aggressive type of tumor in the central nervous system and is characterized by resistance to therapy and abundant vasculature. Tumor vessels contribute to the growth of GB, and the tumor microenvironment is thought to influence tumor vessels. We evaluated the molecular communication between human GB cells and human brain microvascular endothelial cells (HBMEC) in vitro. MATERIALS AND METHODS: We investigated whether GB-conditioned media (GB-CM) influenced HBMEC proliferation and migration, as well as the levels of MMP-9, CXCL12, CXCR4, CXCR7, VEGFs, VEGFR-2, and WNT5a in HBMEC. RESULTS: Although HBMEC proliferation was not modified, increased HBMEC migration was detected after GB-CM treatment. Furthermore, treatment of HBMEC with GB-CM resulted in increased levels of MMP-9 and CXCR4. The levels of WNT5a, VEGFs and VEGFR-2 were not affected. CONCLUSION: GB-secreted factors lead to increased endothelial cell migration and to increased levels of MMP-9 and CXCR4.


Assuntos
Neoplasias Encefálicas/patologia , Encéfalo/patologia , Movimento Celular , Células Endoteliais/patologia , Glioblastoma/patologia , Metaloproteinase 9 da Matriz/metabolismo , Receptores CXCR4/metabolismo , Neoplasias Encefálicas/genética , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Quimiocina CXCL12/metabolismo , Meios de Cultivo Condicionados/farmacologia , Células Endoteliais/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Glioblastoma/genética , Humanos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores CXCR/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Proteína Wnt-5a/genética , Proteína Wnt-5a/metabolismo
7.
Cell Prolif ; 53(5): e12819, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32372504

RESUMO

OBJECTIVE: The objective of this study was to explore characteristics of bone marrow mesenchymal stromal cells (BM-MSCs) derived from patients with myelodysplastic syndrome (MDS) and multiple myeloma (MM). METHODS: BM-MSCs were recovered from 17 of MDS patients, 23 of MM patients and 9 healthy donors and were passaged until proliferation stopped. General characteristics and gene expression profiles of MSCs were analysed. In vitro, ex vivo coculture, immunohistochemistry and knockdown experiments were performed to verify gene expression changes. RESULTS: BM-MSCs failed to culture in 35.0% of patients and 50.0% of recovered BM-MSCs stopped to proliferate before passage 6. MDS- and MM-MSCs shared characteristics including decreased osteogenesis, increased angiogenesis and senescence-associated molecular pathways. In vitro and ex vivo experiments showed disease-specific changes such as neurogenic tendency in MDS-MSCs and cardiomyogenic tendency in MM-MSCs. Although the age of normal control was younger than patients and telomere length was shorter in patient's BM-MSCs, they were not different according to disease category nor degree of proliferation. Specifically, poorly proliferation BM-MSCs showed CDKN2A overexpression and CXCL12 downregulation. Immunohistochemistry of BM biopsy demonstrated that CDKN2A was intensely accumulation in perivascular BM-MSCs failed to culture. Interestingly, patient's BM-MSCs revealed improved proliferation activity after CDKN2A knockdown. CONCLUSION: These results collectively indicate that MDS-MSCs and MM-MSCs have common and different alterations at various degrees. Hence, it is necessary to evaluate their alteration status using representative markers such as CDKN2A expression.


Assuntos
Medula Óssea/patologia , Células-Tronco Mesenquimais/patologia , Mieloma Múltiplo/patologia , Síndromes Mielodisplásicas/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Medula Óssea/metabolismo , Células da Medula Óssea/metabolismo , Células da Medula Óssea/patologia , Diferenciação Celular/fisiologia , Proliferação de Células/fisiologia , Células Cultivadas , Quimiocina CXCL12/metabolismo , Feminino , Humanos , Masculino , Células-Tronco Mesenquimais/metabolismo , Pessoa de Meia-Idade , Mieloma Múltiplo/metabolismo , Síndromes Mielodisplásicas/metabolismo , Osteogênese/fisiologia , Adulto Jovem
8.
PLoS One ; 15(4): e0232536, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32353075

RESUMO

Sperm migration towards an oocyte in the female reproductive tract is an important step for successful fertilization. Although several sperm-chemotactic factors have been identified in mammals, it is unclear whether these chemoattractants contribute to sperm migration towards an oocyte that is the final destination for sperm. Furthermore, chemoattractants for bovine sperm are still undiscovered even though the follicular fluid attracts sperm in cattle. Here, we demonstrated that a single bovine cumulus-oocyte complex (COC) had the ability to attract sperm, suggesting that the COC secreted sperm chemoattractants. We identified stromal cell-derived factor 1 (SDF1), which was expressed in COCs, and its receptor CXCR4 in sperm, as a candidate. Our results showed that bovine sperm preferentially migrated to the area with a high SDF1 concentration and occasionally showed turn movements by asymmetric flagellar bends during the migration. We also demonstrated that increasing the intracellular Ca2+ concentration via Ca2+ channels was related to SDF1-induced sperm chemotaxis. Finally, a CXCR4 inhibitor significantly suppressed the in vitro bovine sperm migration towards a COC. Taken together, we propose that SDF1 is a chemotactic factor for bovine sperm to regulate their migration towards an oocyte via the CXCR4 receptor.


Assuntos
Quimiocina CXCL12/metabolismo , Quimiotaxia/fisiologia , Receptores CXCR4/metabolismo , Motilidade Espermática/fisiologia , Animais , Bovinos , Células do Cúmulo/metabolismo , Feminino , Fertilização In Vitro/veterinária , Microscopia Intravital , Masculino , Oócitos/metabolismo , Espermatozoides/fisiologia
9.
PLoS One ; 15(5): e0232965, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32384110

RESUMO

Fibroblasts as key components of tumor microenvironment show different features in the interaction with cancer cells. Although, Normal fibroblasts demonstrate anti-tumor effects, cancer associated fibroblasts are principal participant in tumor growth and invasion. The ambiguity of fibroblasts function can be regarded as two heads of its behavioral spectrum and can be subjected for mathematical modeling to identify their switching behavior. In this research, an agent-based model of mutual interactions between fibroblast and cancer cell was created. The proposed model is based on nonlinear differential equations which describes biochemical reactions of the main factors involved in fibroblasts and cancer cells communication. Also, most of the model parameters are estimated using hybrid unscented Kalman filter. The interactions between two cell types are illustrated by the dynamic modeling of TGFß and LIF pathways as well as their crosstalk. Using analytical and computational approaches, reciprocal effects of cancer cells and fibroblasts are constructed and the role of signaling molecules in tumor progression or prevention are determined. Finally, the model is validated using a set of experimental data. The proposed dynamic modeling might be useful for designing more efficient therapies in cancer metastasis treatment and prevention.


Assuntos
Fibroblastos Associados a Câncer/metabolismo , Modelos Biológicos , Microambiente Tumoral/fisiologia , Células A549 , Comunicação Celular/fisiologia , Quimiocina CXCL12/metabolismo , Simulação por Computador , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Fator Inibidor de Leucemia/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Dinâmica não Linear , Transdução de Sinais/fisiologia , Análise de Sistemas , Fator de Crescimento Transformador beta/metabolismo
10.
Nat Immunol ; 21(6): 649-659, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32424359

RESUMO

Efficient generation of germinal center (GC) responses requires directed movement of B cells between distinct microenvironments underpinned by specialized B cell-interacting reticular cells (BRCs). How BRCs are reprogrammed to cater to the developing GC remains unclear, and studying this process is largely hindered by incomplete resolution of the cellular composition of the B cell follicle. Here we used genetic targeting of Cxcl13-expressing cells to define the molecular identity of the BRC landscape. Single-cell transcriptomic analysis revealed that BRC subset specification was predetermined in the primary B cell follicle. Further topological remodeling of light and dark zone follicular dendritic cells required CXCL12-dependent crosstalk with B cells and dictated GC output by retaining B cells in the follicle and steering their interaction with follicular helper T cells. Together, our results reveal that poised BRC-defined microenvironments establish a feed-forward system that determines the efficacy of the GC reaction.


Assuntos
Escuridão , Células Dendríticas Foliculares/imunologia , Células Dendríticas Foliculares/metabolismo , Centro Germinativo/imunologia , Centro Germinativo/metabolismo , Imunomodulação/efeitos da radiação , Luz , Animais , Linfócitos B/imunologia , Linfócitos B/metabolismo , Biomarcadores , Comunicação Celular , Quimiocina CXCL12/metabolismo , Camundongos , Camundongos Transgênicos , Fenótipo , Análise de Célula Única , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo
11.
PLoS One ; 15(5): e0233751, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32470079

RESUMO

Mesenchymal stromal cells are an important component of the bone marrow hematopoietic niche. Prior studies showed that signaling from members of the transforming growth factor (TGF) superfamily in mesenchymal stromal cells is required for normal niche development. Here, we assessed the impact of TGF family signaling on niche maintenance and stress responses by deleting Smad4 in mesenchymal stromal cells at birth, thereby abrogating canonical TGF signaling. No alteration in the number or spatial organization of CXCL12-abundant reticular (CAR) cells, osteoblasts, or adipocytes was observed in Osx-Cre, Smad4fl/fl mice, and expression of key niche factors was normal. Basal hematopoiesis and stress erythropoiesis responses to acute hemolytic anemia were normal. TGF-ß potently inhibits stromal CXCL12 expression in vitro; however, G-CSF induced decreases in bone marrow CXCL12 expression and subsequent hematopoietic stem/progenitor cell mobilization were normal in Osx-Cre, Tgfbr2fl/fl mice, in which all TGF-ß signaling in mesenchymal stromal is lost. Finally, although a prior study showed that TGF-ß enhances recovery from myeloablative therapy, hematopoietic recovery following single or multiple doses of 5-flurauracil were normal in Osx-Cre, Tgfbr2fl/fl mice. Collectively, these data suggest that TGF family member signaling in mesenchymal stromal cells is dispensable for hematopoietic niche maintenance under basal and stress conditions.


Assuntos
Anemia Hemolítica/metabolismo , Eritropoese , Células-Tronco Hematopoéticas , Células-Tronco Mesenquimais , Fator de Crescimento Transformador beta/fisiologia , Fatores de Crescimento Transformadores/fisiologia , Doença Aguda , Anemia Hemolítica/patologia , Animais , Medula Óssea/metabolismo , Medula Óssea/patologia , Células Cultivadas , Quimiocina CXCL12/metabolismo , Feminino , Fator Estimulador de Colônias de Granulócitos/farmacologia , Mobilização de Células-Tronco Hematopoéticas , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/patologia , Masculino , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/patologia , Camundongos , Camundongos Endogâmicos C57BL , Nicho de Células-Tronco
12.
PLoS Biol ; 18(4): e3000656, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32271748

RESUMO

Chemokines and their receptors are orchestrators of cell migration in humans. Because dysregulation of the receptor-chemokine system leads to inflammation and cancer, both chemokines and receptors are highly sought therapeutic targets. Yet one of the barriers for their therapeutic targeting is the limited understanding of the structural principles behind receptor-chemokine recognition and selectivity. The existing structures do not include CXC subfamily complexes and lack information about the receptor distal N-termini, despite the importance of the latter in signaling, regulation, and bias. Here, we report the discovery of the geometry of the complex between full-length CXCR4, a prototypical CXC receptor and driver of cancer metastasis, and its endogenous ligand CXCL12. By comprehensive disulfide cross-linking, we establish the existence and the structure of a novel interface between the CXCR4 distal N-terminus and CXCL12 ß1-strand, while also recapitulating earlier findings from nuclear magnetic resonance, modeling and crystallography of homologous receptors. A cross-linking-informed high-resolution model of the CXCR4-CXCL12 complex pinpoints the interaction determinants and reveals the occupancy of the receptor major subpocket by the CXCL12 proximal N terminus. This newly found positioning of the chemokine proximal N-terminus provides a structural explanation of CXC receptor-chemokine selectivity against other subfamilies. Our findings challenge the traditional two-site understanding of receptor-chemokine recognition, suggest the possibility of new affinity and signaling determinants, and fill a critical void on the structural map of an important class of therapeutic targets. These results will aid the rational design of selective chemokine-receptor targeting small molecules and biologics with novel pharmacology.


Assuntos
Quimiocina CXCL12/química , Quimiocina CXCL12/metabolismo , Receptores CXCR4/química , Receptores CXCR4/metabolismo , Animais , Sítios de Ligação , Western Blotting , Quimiocina CXCL12/genética , Cisteína/química , Cisteína/genética , Dissulfetos/química , Citometria de Fluxo , Células HEK293 , Humanos , Insetos/citologia , Modelos Moleculares , Mutação , Conformação Proteica , Domínios e Motivos de Interação entre Proteínas , Receptores CXCR4/genética , beta-Arrestinas/metabolismo
13.
Am J Respir Cell Mol Biol ; 63(2): 244-254, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32275835

RESUMO

Delayed lung repair leads to alveolopleural fistulae, which are a major cause of morbidity after lung resections. We have reported that intrapleural hypercapnia is associated with delayed lung repair after lung resection. Here, we provide new evidence that hypercapnia delays wound closure of both large airway and alveolar epithelial cell monolayers because of inhibition of epithelial cell migration. Cell migration and airway epithelial wound closure were dependent on Rac1-GTPase activation, which was suppressed by hypercapnia directly through the upregulation of AMP kinase and indirectly through inhibition of injury-induced NF-κB-mediated CXCL12 (pleural CXC motif chemokine 12) release, respectively. Both these pathways were independently suppressed, because dominant negative AMP kinase rescued the effects of hypercapnia on Rac1-GTPase in uninjured resting cells, whereas proteasomal inhibition reversed the NF-κB-mediated CXCL12 release during injury. Constitutive overexpression of Rac1-GTPase rescued the effects of hypercapnia on both pathways as well as on wound healing. Similarly, exogenous recombinant CXCL12 reversed the effects of hypercapnia through Rac1-GTPase activation by its receptor, CXCR4. Moreover, CXCL12 transgenic murine recipients of orthotopic tracheal transplantation were protected from hypercapnia-induced inhibition of tracheal epithelial cell migration and wound repair. In patients undergoing lobectomy, we found inverse correlation between intrapleural carbon dioxide and pleural CXCL12 levels as well as between CXCL12 levels and alveolopleural leak. Accordingly, we provide first evidence that high carbon dioxide levels impair lung repair by inhibiting epithelial cell migration through two distinct pathways, which can be restored by recombinant CXCL12.


Assuntos
Dióxido de Carbono/efeitos adversos , Lesão Pulmonar/fisiopatologia , Pulmão/efeitos dos fármacos , Cicatrização/efeitos dos fármacos , Células Epiteliais Alveolares/efeitos dos fármacos , Células Epiteliais Alveolares/metabolismo , Animais , Movimento Celular/efeitos dos fármacos , Quimiocina CXCL12/metabolismo , Feminino , Humanos , Hipercapnia/metabolismo , Pulmão/metabolismo , Lesão Pulmonar/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , NF-kappa B/metabolismo , Receptores CXCR4/metabolismo , Transdução de Sinais/efeitos dos fármacos
14.
Nat Commun ; 11(1): 1631, 2020 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-32242005

RESUMO

In the developing cortex, postmigratory neurons accumulate in the cortical plate (CP) to properly differentiate consolidating subtype identities. Microglia, despite their extensive surveying activity, temporarily disappear from the midembryonic CP. However, the mechanism and significance of this absence are unknown. Here, we show that microglia bidirectionally migrate via attraction by CXCL12 released from the meninges and subventricular zone and thereby exit the midembryonic CP. Upon nonphysiological excessive exposure to microglia in vivo or in vitro, young postmigratory and in vitro-grown CP neurons showed abnormal differentiation with disturbed expression of the subtype-associated transcription factors and genes implicated in functional neuronal maturation. Notably, this effect is primarily attributed to interleukin 6 and type I interferon secreted by microglia. These results suggest that "sanctuarization" from microglia in the midembryonic CP is required for neurons to appropriately fine-tune the expression of molecules needed for proper differentiation, thus securing the establishment of functional cortical circuit.


Assuntos
Córtex Cerebral/embriologia , Microglia/metabolismo , Neurogênese , Neurônios/citologia , Animais , Movimento Celular , Córtex Cerebral/metabolismo , Quimiocina CXCL12/metabolismo , Interferon Tipo I/metabolismo , Interleucina-6/metabolismo , Camundongos , Neurônios/metabolismo
15.
Breast Cancer Res ; 22(1): 30, 2020 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-32188473

RESUMO

BACKGROUND: Breast cancer is rare in men, but management is focused on tumor characteristics commonly found in female breast cancer. The tumor microenvironment of male breast cancer is less well understood, and insight may improve male breast cancer management. The hepatocyte growth factor (HGF)/c-MET axis and the stromal cell-derived factor-1 (CXCL12)/C-X-C chemokine receptor type 4 (CXCR4) axis are prognostic in women with breast cancer. We aimed to investigate these factors in male breast cancer and correlate them with patient survival. METHODS: From 841 Dutch males with breast cancer who were enrolled in the EORTC 10085/TBCRC/BIG/NABCG International Male Breast Cancer Program (NCT01101425) and diagnosed between 1990 and 2010, archival primary tumor samples were collected. Tissue microarrays were constructed with 3 cores per sample and used for immunohistochemical analysis of HGF, c-MET, CXCL12, and CXCR4. Overall survival (OS) of the patients without metastases (M0) was analyzed using the Kaplan-Meier method. The value of the markers regarding OS was determined using univariable and multivariable Cox regression analyses, providing hazard ratios (HRs) and 95% confidence intervals (95% CIs). RESULTS: Of 720 out of 841 patients, sufficient tissue was available for analysis; 487 out of 720 patients had M0 disease. Patients with high HGF expression and high CXCL12 expression had a superior OS (low vs high expression of both markers, 7.5 vs 13.0 years, hazard ratio [HR] 0.64, 95% CI 0.49-0.84, P = 0.001 [HGF]; 9.1 vs 15.3 years, HR 0.63, 95% CI 0.45-0.87, P = 0.005 [CXCL12]). Multivariate analysis identified HGF as an independent predictor for OS (HR 0.64, 95% CI 0.47-0.88, P = 0.001). CONCLUSIONS: HGF and CXCL12 tumor expression appear to identify male breast cancer patients with a relatively good prognosis. Possibly, this could support male breast cancer-specific management strategies in the future.


Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias da Mama Masculina/mortalidade , Quimiocina CXCL12/metabolismo , Fator de Crescimento de Hepatócito/metabolismo , Microambiente Tumoral , Idoso , Neoplasias da Mama Masculina/metabolismo , Neoplasias da Mama Masculina/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Transdução de Sinais , Taxa de Sobrevida
16.
Immunity ; 52(3): 542-556.e13, 2020 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-32187520

RESUMO

Fibrosis is an incurable disorder of unknown etiology. Segregated-nucleus-containing atypical monocytes (SatMs) are critical for the development of fibrosis. Here we examined the mechanisms that recruit SatMs to pre-fibrotic areas. A screen based on cytokine expression in the fibrotic lung revealed that the chemokine Cxcl12, which is produced by apoptotic nonhematopoietic cells, was essential for SatM recruitment. Analyses of lung tissues at fibrosis onset showed increased expression of Rbm7, a component of the nuclear exosome targeting complex. Rbm7 deletion suppressed bleomycin-induced fibrosis and at a cellular level, suppressed apoptosis of nonhematopoietic cells. Mechanistically, Rbm7 bound to noncoding (nc)RNAs that form subnuclear bodies, including Neat1 speckles. Dysregulated expression of Rbm7 resulted in the nuclear degradation of Neat1 speckles, the dispersion of the DNA repair protein BRCA1, and the triggering of apoptosis. Thus, Rbm7 in epithelial cells plays a critical role in the development of fibrosis by regulating ncRNA decay and thereby the production of chemokines that recruit SatMs.


Assuntos
Apoptose/imunologia , Núcleo Celular/imunologia , Exossomos/imunologia , Fibrose Pulmonar/imunologia , Proteínas de Ligação a RNA/imunologia , Animais , Apoptose/genética , Núcleo Celular/genética , Núcleo Celular/metabolismo , Quimiocina CXCL12/imunologia , Quimiocina CXCL12/metabolismo , Exossomos/genética , Exossomos/metabolismo , Regulação da Expressão Gênica/imunologia , Células HEK293 , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Monócitos/imunologia , Monócitos/metabolismo , Células NIH 3T3 , Fibrose Pulmonar/genética , Fibrose Pulmonar/metabolismo , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo
17.
Life Sci ; 249: 117534, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-32156548

RESUMO

Tumors are dynamic tissue masses, so requiring continuous exposure to the host cells, nurturing them into pave a path for tumor growth and metastasis. C-X-C chemokine ligand 12 (CXCL12)/C-X-C chemokine receptor type 4 (CXCR4) is the key signaling for such aim. Gathering knowledge about the activity within this axis would deepen our insight into the utmost importance this signaling taken to attract and cross-connect multiple cells within the tumor microenvironment (TME) aiming for tumor progression and metastasis. The concept behind this review is to underscore the multi-tasking roles taken by CXCL12/CXCR4 signaling in tumor metastasis, and to also suggest some strategies to target the activities within this axis.


Assuntos
Quimiocina CXCL12/metabolismo , Metástase Neoplásica , Neoplasias/patologia , Receptores CXCR4/metabolismo , Microambiente Tumoral , Humanos , Neoplasias/metabolismo , Transdução de Sinais
18.
Mol Carcinog ; 59(4): 390-398, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32037613

RESUMO

Brain metastasis is a leading cause of death worldwide, but the mechanism involved remains unclear. Stromal cell-derived factor-1 (SDF-1)/C-X-C motif chemokine receptor 4 (CXCR4) signaling has been reported to induce the directed metastasis of cancers, and adenosine A2A receptor activation suppresses the SDF-1/CXCR4 interaction. However, whether A2A receptor activation implicates the SDF-1/CXCR4 signaling pathway and thus modulates brain metastasis remains unclear. In this study, Western blot was performed to evaluate the protein levels. Cell invasion and migration assays were used to estimate the metastasis ability of PC-9 cells. The viability of cells was demonstrated by lactate dehydrogenase and cell proliferation assays. And the findings in vitro were further identified in nude mice. Notably, adenosine A2A receptor activation inhibited the proliferation and viability of PC-9 cells and thus suppressed the brain metastasis. A2A receptor stimulation protected the function of blood-brain barrier (BBB). The suppression of brain metastasis and the protection of BBB by A2A receptor relied on SDF-1/CXCR4 signaling, and treatment using A2A receptor agonist and CXCR4 antagonist protected the nude mice from malignancy metastasis in vivo. Adenosine A2A receptor activation suppressed the brain metastasis by implicating the SDF-1/CXCR4 axis and protecting the BBB.


Assuntos
Agonistas do Receptor A2 de Adenosina/farmacologia , Barreira Hematoencefálica/efeitos dos fármacos , Neoplasias Encefálicas/prevenção & controle , Quimiocina CXCL12/metabolismo , Neoplasias Pulmonares/prevenção & controle , Receptor A2A de Adenosina/metabolismo , Receptores CXCR4/antagonistas & inibidores , Adenosina/análogos & derivados , Adenosina/farmacologia , Animais , Barreira Hematoencefálica/metabolismo , Neoplasias Encefálicas/secundário , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Compostos Heterocíclicos/farmacologia , Humanos , Neoplasias Pulmonares/patologia , Camundongos Endogâmicos BALB C , Camundongos Nus , Fenetilaminas/farmacologia , Receptores CXCR4/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto/métodos
19.
Nat Cell Biol ; 22(3): 266-273, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32042179

RESUMO

Chemoattractant gradients frequently guide migrating cells. To achieve the most directional signal, such gradients should be maintained with concentrations around the dissociation constant (Kd)1-6 of the chemoreceptor. Whether this actually occurs in animals is unknown. Here we investigate whether a moving tissue, the zebrafish posterior lateral line primordium, buffers its attractant in this concentration range to achieve robust migration. We find that the Cxcl12 (also known as Sdf1) attractant gradient ranges from 0 to 12 nM, values similar to the 3.4 nM Kd of its receptor Cxcr4. When we increase the Kd of Cxcl12 for Cxcr4, primordium migration is less directional. Furthermore, a negative-feedback loop between Cxcl12 and its clearance receptor Ackr3 (also known as Cxcr7) regulates the Cxcl12 concentrations. Breaking this negative feedback by blocking the phosphorylation of the cytoplasmic tail of Ackr3 also results in less directional primordium migration. Thus, directed migration of the primordium is dependent on a close match between the Cxcl12 concentration and the Kd of Cxcl12 for Cxcr4, which is maintained by buffering of the chemokine levels. Quantitative modelling confirms the plausibility of this mechanism. We anticipate that buffering of attractant concentration is a general mechanism for ensuring robust cell migration.


Assuntos
Movimento Celular , Quimiocinas/metabolismo , Animais , Animais Geneticamente Modificados , Linhagem Celular , Quimiocina CXCL12/metabolismo , Retroalimentação Fisiológica , Humanos , Receptores CXCR/metabolismo , Receptores CXCR4/metabolismo , Peixe-Zebra/embriologia , Peixe-Zebra/genética , Peixe-Zebra/metabolismo , Proteínas de Peixe-Zebra/metabolismo
20.
Am J Physiol Renal Physiol ; 318(3): F741-F753, 2020 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-32068458

RESUMO

Glomerular parietal epithelial cell (PEC) activation, as revealed by de novo expression of CD44 and cell migration toward the injured filtration barrier, is a hallmark of podocyte injury-driven focal segmental glomerulosclerosis (FSGS). However, the signaling pathway that mediates activation of PECs in response to podocyte injury is unknown. The present study focused on CD44 signaling, particularly the roles of two CD44-related chemokines, migration inhibitory factor (MIF) and stromal cell-derived factor 1 (SDF1), and their common receptor, chemokine (C-X-C motif) receptor 4 (CXCR4), in the NEP25/LMB2 mouse podocyte-toxin model of FSGS. In the early phase of the disease, CD44-positive PECs were locally evident on the opposite side of the intact glomerular tuft and subsequently increased in the vicinity of synechiae with podocyte loss. Expression of MIF and SDF1 was first increased in injured podocytes and subsequently transferred to activated PECs expressing CD44 and CXCR4. In an immortalized mouse PEC (mPEC) line, recombinant MIF and SDF1 (rMIF and rSDF1, respectively) individually increased CD44 and CXCR4 mRNA and protein levels. rMIF and rSDF1 stimulated endogenous MIF and SDF1 production. rMIF- and rSDF1-induced mPEC migration was suppressed by CD44 siRNA. However, MIF and SDF1 inhibitors failed to show any impact on proteinuria, podocyte number, and CD44 expression in NEP25/LMB2 mice. Our data suggest that injured podocytes upregulate MIF and SDF1 that stimulate CD44 expression and CD44-mediated migration, which is enhanced by endogenous MIF and SDF1 in PECs. This biphasic expression pattern of the chemokine-CD44 axis in podocytes and PECs may be a novel mechanism of "podocyte-PEC cross-talk" signaling underlying podocyte injury-driven FSGS.


Assuntos
Antígenos de Diferenciação de Linfócitos B/metabolismo , Quimiocina CXCL12/metabolismo , Antígenos de Histocompatibilidade Classe II/metabolismo , Receptores de Hialuronatos/metabolismo , Proteínas Associadas aos Microtúbulos/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Podócitos/fisiologia , Receptores CXCR4/metabolismo , Animais , Antígenos de Diferenciação de Linfócitos B/genética , Cápsula Glomerular , Movimento Celular , Células Cultivadas , Quimiocina CXCL12/genética , Antígenos de Histocompatibilidade Classe II/genética , Receptores de Hialuronatos/genética , Camundongos , Camundongos Endogâmicos , Proteínas Associadas aos Microtúbulos/genética , Proteínas do Tecido Nervoso/genética , Interferência de RNA , Receptores CXCR4/genética , Regulação para Cima
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