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1.
BMC Bioinformatics ; 21(1): 346, 2020 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-32778050

RESUMO

BACKGROUND: While technological advances have made it possible to profile the immune system at high resolution, translating high-throughput data into knowledge of immune mechanisms has been challenged by the complexity of the interactions underlying immune processes. Tools to explore the immune network are critical for better understanding the multi-layered processes that underlie immune function and dysfunction, but require a standardized network map of immune interactions. To facilitate this we have developed ImmunoGlobe, a manually curated intercellular immune interaction network extracted from Janeway's Immunobiology textbook. RESULTS: ImmunoGlobe is the first graphical representation of the immune interactome, and is comprised of 253 immune system components and 1112 unique immune interactions with detailed functional and characteristic annotations. Analysis of this network shows that it recapitulates known features of the human immune system and can be used uncover novel multi-step immune pathways, examine species-specific differences in immune processes, and predict the response of immune cells to stimuli. ImmunoGlobe is publicly available through a user-friendly interface at www.immunoglobe.org and can be downloaded as a computable graph and network table. CONCLUSION: While the fields of proteomics and genomics have long benefited from network analysis tools, no such tool yet exists for immunology. ImmunoGlobe provides a ground truth immune interaction network upon which such tools can be built. These tools will allow us to predict the outcome of complex immune interactions, providing mechanistic insight that allows us to precisely modulate immune responses in health and disease.


Assuntos
Comunicação Celular , Curadoria de Dados , Espaço Extracelular/metabolismo , Sistema Imunitário/metabolismo , Mapas de Interação de Proteínas , Software , Biologia de Sistemas , Animais , Humanos , Camundongos , Modelos Imunológicos
2.
PLoS One ; 15(7): e0235546, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32609743

RESUMO

Resistin and resistin-like molecules are pleiotropic cytokines that are involved in inflammatory diseases. Our previous work suggested that resistin has the potential to be used as a biomarker and therapeutic target for human pulmonary arterial hypertension. However, data are limited on the distribution of resistin in healthy human organs. In this study, we used our newly developed anti-human resistin (hResistin) antibody to immunohistochemically detect the expression, localization, and intracellular/extracellular compartmentalization of hResistin in a full human tissue panel from healthy individuals. The potential cross reactivity of this monoclonal anti-hResistin IgG1 with normal human tissues also was verified. Results showed that hResistin is broadly distributed and principally localized in the cytoplasmic granules of macrophages scattered in the interstitium of most human tissues. Bone marrow hematopoietic precursor cells also exhibited hResistin signals in their cytoplasmic granules. Additionally, hResistin labeling was observed in the cytoplasm of nervous system cells. Notably, the cytokine activity of hResistin was illustrated by positively stained extracellular material in most human tissues. These data indicate that our generated antibody binds to the secreted hResistin and support its potential use for immunotherapy to reduce circulating hResistin levels in human disease. Our findings comprehensively document the basal expression patterns of hResistin protein in normal human tissues, suggest a critical role of this cytokine in normal and pathophysiologic inflammatory processes, and offer key insights for using our antibody in future pharmacokinetic studies and immunotherapeutic strategies.


Assuntos
Anticorpos Monoclonais/imunologia , Regulação da Expressão Gênica , Resistina/imunologia , Resistina/metabolismo , Espaço Extracelular/metabolismo , Células HEK293 , Humanos , Imuno-Histoquímica , Espaço Intracelular/metabolismo , Especificidade de Órgãos , Transporte Proteico
3.
Nature ; 584(7820): 291-297, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32728216

RESUMO

The majority of therapies that target individual proteins rely on specific activity-modulating interactions with the target protein-for example, enzyme inhibition or ligand blocking. However, several major classes of therapeutically relevant proteins have unknown or inaccessible activity profiles and so cannot be targeted by such strategies. Protein-degradation platforms such as proteolysis-targeting chimaeras (PROTACs)1,2 and others (for example, dTAGs3, Trim-Away4, chaperone-mediated autophagy targeting5 and SNIPERs6) have been developed for proteins that are typically difficult to target; however, these methods involve the manipulation of intracellular protein degradation machinery and are therefore fundamentally limited to proteins that contain cytosolic domains to which ligands can bind and recruit the requisite cellular components. Extracellular and membrane-associated proteins-the products of 40% of all protein-encoding genes7-are key agents in cancer, ageing-related diseases and autoimmune disorders8, and so a general strategy to selectively degrade these proteins has the potential to improve human health. Here we establish the targeted degradation of extracellular and membrane-associated proteins using conjugates that bind both a cell-surface lysosome-shuttling receptor and the extracellular domain of a target protein. These initial lysosome-targeting chimaeras, which we term LYTACs, consist of a small molecule or antibody fused to chemically synthesized glycopeptide ligands that are agonists of the cation-independent mannose-6-phosphate receptor (CI-M6PR). We use LYTACs to develop a CRISPR interference screen that reveals the biochemical pathway for CI-M6PR-mediated cargo internalization in cell lines, and uncover the exocyst complex as a previously unidentified-but essential-component of this pathway. We demonstrate the scope of this platform through the degradation of therapeutically relevant proteins, including apolipoprotein E4, epidermal growth factor receptor, CD71 and programmed death-ligand 1. Our results establish a modular strategy for directing secreted and membrane proteins for lysosomal degradation, with broad implications for biochemical research and for therapeutics.


Assuntos
Espaço Extracelular/metabolismo , Lisossomos/metabolismo , Proteínas de Membrana/metabolismo , Proteólise , Proteínas Recombinantes de Fusão/metabolismo , Animais , Anticorpos/química , Anticorpos/metabolismo , Antígenos CD/metabolismo , Apolipoproteína E4/metabolismo , Antígeno B7-H1/metabolismo , Sistemas CRISPR-Cas , Linhagem Celular , Receptores ErbB/metabolismo , Feminino , Glicopeptídeos/síntese química , Glicopeptídeos/metabolismo , Humanos , Ligantes , Proteínas de Membrana/química , Camundongos , Domínios Proteicos , Transporte Proteico , Receptor IGF Tipo 2/metabolismo , Receptores da Transferrina/metabolismo , Proteínas Recombinantes de Fusão/síntese química , Proteínas Recombinantes de Fusão/química , Solubilidade , Especificidade por Substrato
4.
Nature ; 584(7821): 410-414, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32641833

RESUMO

In metazoans, the secreted proteome participates in intercellular signalling and innate immunity, and builds the extracellular matrix scaffold around cells. Compared with the relatively constant intracellular environment, conditions for proteins in the extracellular space are harsher, and low concentrations of ATP prevent the activity of intracellular components of the protein quality-control machinery. Until now, only a few bona fide extracellular chaperones and proteases have been shown to limit the aggregation of extracellular proteins1-5. Here we performed a systematic analysis of the extracellular proteostasis network in Caenorhabditis elegans with an RNA interference screen that targets genes that encode the secreted proteome. We discovered 57 regulators of extracellular protein aggregation, including several proteins related to innate immunity. Because intracellular proteostasis is upregulated in response to pathogens6-9, we investigated whether pathogens also stimulate extracellular proteostasis. Using a pore-forming toxin to mimic a pathogenic attack, we found that C. elegans responded by increasing the expression of components of extracellular proteostasis and by limiting aggregation of extracellular proteins. The activation of extracellular proteostasis was dependent on stress-activated MAP kinase signalling. Notably, the overexpression of components of extracellular proteostasis delayed ageing and rendered worms resistant to intoxication. We propose that enhanced extracellular proteostasis contributes to systemic host defence by maintaining a functional secreted proteome and avoiding proteotoxicity.


Assuntos
Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/microbiologia , Espaço Extracelular/metabolismo , Agregados Proteicos , Proteostase , Envelhecimento/metabolismo , Animais , Caenorhabditis elegans/citologia , Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Sistema de Sinalização das MAP Quinases , Agregação Patológica de Proteínas/prevenção & controle , Proteoma/genética , Proteoma/metabolismo , Interferência de RNA
5.
Nat Commun ; 11(1): 3440, 2020 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-32651387

RESUMO

In recent years, exploration of the brain extracellular space (ECS) has made remarkable progress, including nanoscopic characterizations. However, whether ECS precise conformation is altered during brain pathology remains unknown. Here we study the nanoscale organization of pathological ECS in adult mice under degenerative conditions. Using electron microscopy in cryofixed tissue and single nanotube tracking in live brain slices combined with super-resolution imaging analysis, we find enlarged ECS dimensions and increased nanoscale diffusion after α-synuclein-induced neurodegeneration. These animals display a degraded hyaluronan matrix in areas close to reactive microglia. Furthermore, experimental hyaluronan depletion in vivo reduces dopaminergic cell loss and α-synuclein load, induces microgliosis and increases ECS diffusivity, highlighting hyaluronan as diffusional barrier and local tissue organizer. These findings demonstrate the interplay of ECS, extracellular matrix and glia in pathology, unraveling ECS features relevant for the α-synuclein propagation hypothesis and suggesting matrix manipulation as a disease-modifying strategy.


Assuntos
Encéfalo/metabolismo , Espaço Extracelular/metabolismo , Ácido Hialurônico/metabolismo , Sinucleinopatias/metabolismo , Animais , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microglia/metabolismo , Microglia/ultraestrutura , Microscopia Eletrônica , Doença de Parkinson/metabolismo , Espectroscopia de Luz Próxima ao Infravermelho
6.
Anticancer Res ; 40(7): 3931-3937, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32620634

RESUMO

BACKGROUND/AIM: Extracellular water-to-total body water ratio (ECW/TBW) measured by bioelectrical impedance analysis (BIA) reportedly predicts clinical outcomes of various diseases. The aim of this retrospective study was to examine the association between ECW/TBW and therapeutic durability of chemotherapy and/or immune checkpoint inhibitors in advanced lung cancer. PATIENTS AND METHODS: Patients with advanced lung cancer underwent BIA before chemotherapy and/or treatment with immune checkpoint inhibitors at our hospital between June 2018 and November 2019. RESULTS: Of 75 patients, 18 with ECW/TBW ≥0.4 were assigned to the overhydrated group (OH-G) and 57 patients ECW/TBW <0.4 were assigned to the non-overhydrated group (NOH-G). The median time-to-treatment failure was significantly shorter in the OH-G than in the NOH-G (p=0.003). Multivariate analysis revealed that ECW/TBW ≥0.4 predicted treatment failure [hazard ratio (HR)=2.508, 95% confidence interval (CI)=1.19-5.27; p=0.01]. CONCLUSION: The ECW/TBW may be an objective parameter for predicting therapeutic durability in advanced lung cancer.


Assuntos
Antineoplásicos/uso terapêutico , Água Corporal/metabolismo , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/metabolismo , Água/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos Imunológicos/uso terapêutico , Composição Corporal , Impedância Elétrica , Espaço Extracelular/metabolismo , Humanos , Neoplasias Pulmonares/patologia , Pessoa de Meia-Idade , Estudos Retrospectivos , Taxa de Sobrevida
7.
PLoS Biol ; 18(6): e3000722, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32569301

RESUMO

Inflammation and infection can trigger local tissue Na+ accumulation. This Na+-rich environment boosts proinflammatory activation of monocyte/macrophage-like cells (MΦs) and their antimicrobial activity. Enhanced Na+-driven MΦ function requires the osmoprotective transcription factor nuclear factor of activated T cells 5 (NFAT5), which augments nitric oxide (NO) production and contributes to increased autophagy. However, the mechanism of Na+ sensing in MΦs remained unclear. High extracellular Na+ levels (high salt [HS]) trigger a substantial Na+ influx and Ca2+ loss. Here, we show that the Na+/Ca2+ exchanger 1 (NCX1, also known as solute carrier family 8 member A1 [SLC8A1]) plays a critical role in HS-triggered Na+ influx, concomitant Ca2+ efflux, and subsequent augmented NFAT5 accumulation. Moreover, interfering with NCX1 activity impairs HS-boosted inflammatory signaling, infection-triggered autolysosome formation, and subsequent antibacterial activity. Taken together, this demonstrates that NCX1 is able to sense Na+ and is required for amplifying inflammatory and antimicrobial MΦ responses upon HS exposure. Manipulating NCX1 offers a new strategy to regulate MΦ function.


Assuntos
Macrófagos/metabolismo , Trocador de Sódio e Cálcio/metabolismo , Sódio/metabolismo , Processamento Alternativo/genética , Animais , Cálcio/metabolismo , Espaço Extracelular/metabolismo , Inativação Gênica/efeitos dos fármacos , Ativação do Canal Iônico/efeitos dos fármacos , Íons , Lipopolissacarídeos/farmacologia , Macrófagos/efeitos dos fármacos , Camundongos , Óxido Nítrico/biossíntese , Células RAW 264.7 , Cloreto de Sódio/farmacologia
8.
Nat Commun ; 11(1): 2092, 2020 04 29.
Artigo em Inglês | MEDLINE | ID: mdl-32350252

RESUMO

Small extracellular vesicles called exosomes affect multiple autocrine and paracrine cellular phenotypes. Understanding the function of exosomes requires a variety of tools, including live imaging. Our previous live-cell reporter, pHluorin-CD63, allows dynamic subcellular monitoring of exosome secretion in migrating and spreading cells. However, dim fluorescence and the inability to make stably-expressing cell lines limit its use. We incorporated a stabilizing mutation in the pHluorin moiety, M153R, which now exhibits higher, stable expression in cells and superior monitoring of exosome secretion. Using this improved construct, we visualize secreted exosomes in 3D culture and in vivo and identify a role for exosomes in promoting leader-follower behavior in 2D and 3D migration. Incorporating an additional non-pH-sensitive red fluorescent tag allows visualization of the exosome lifecycle, including multivesicular body (MVB) trafficking, MVB fusion, exosome uptake and endosome acidification. This reporter will be a useful tool for understanding both autocrine and paracrine roles of exosomes.


Assuntos
Movimento Celular , Exossomos/metabolismo , Sequência de Aminoácidos , Linhagem Celular Tumoral , Sobrevivência Celular , Exossomos/ultraestrutura , Espaço Extracelular/metabolismo , Proteínas de Fluorescência Verde/metabolismo , Humanos , Corpos Multivesiculares/metabolismo , Corpos Multivesiculares/ultraestrutura , Nanopartículas/química , Nanopartículas/ultraestrutura , Tetraspanina 30/química , Tetraspanina 30/metabolismo , Fatores de Tempo
9.
Nat Commun ; 11(1): 2058, 2020 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-32345973

RESUMO

Anaerobic ammonium oxidation (anammox) bacteria contribute significantly to the global nitrogen cycle and play a major role in sustainable wastewater treatment. Anammox bacteria convert ammonium (NH4+) to dinitrogen gas (N2) using intracellular electron acceptors such as nitrite (NO2-) or nitric oxide (NO). However, it is still unknown whether anammox bacteria have extracellular electron transfer (EET) capability with transfer of electrons to insoluble extracellular electron acceptors. Here we show that freshwater and marine anammox bacteria couple the oxidation of NH4+ with transfer of electrons to insoluble extracellular electron acceptors such as graphene oxide or electrodes in microbial electrolysis cells. 15N-labeling experiments revealed that NH4+ was oxidized to N2 via hydroxylamine (NH2OH) as intermediate, and comparative transcriptomics analysis revealed an alternative pathway for NH4+ oxidation with electrode as electron acceptor. Complete NH4+ oxidation to N2 without accumulation of NO2- and NO3- was achieved in EET-dependent anammox. These findings are promising in the context of implementing EET-dependent anammox process for energy-efficient treatment of nitrogen.


Assuntos
Compostos de Amônio/metabolismo , Bactérias/metabolismo , Espaço Extracelular/metabolismo , Anaerobiose , Eletroquímica , Eletrólise , Transporte de Elétrons , Oxirredução , Fatores de Tempo
10.
Nature ; 580(7803): 402-408, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32296183

RESUMO

Global insights into cellular organization and genome function require comprehensive understanding of the interactome networks that mediate genotype-phenotype relationships1,2. Here we present a human 'all-by-all' reference interactome map of human binary protein interactions, or 'HuRI'. With approximately 53,000 protein-protein interactions, HuRI has approximately four times as many such interactions as there are high-quality curated interactions from small-scale studies. The integration of HuRI with genome3, transcriptome4 and proteome5 data enables cellular function to be studied within most physiological or pathological cellular contexts. We demonstrate the utility of HuRI in identifying the specific subcellular roles of protein-protein interactions. Inferred tissue-specific networks reveal general principles for the formation of cellular context-specific functions and elucidate potential molecular mechanisms that might underlie tissue-specific phenotypes of Mendelian diseases. HuRI is a systematic proteome-wide reference that links genomic variation to phenotypic outcomes.


Assuntos
Proteoma/metabolismo , Espaço Extracelular/metabolismo , Humanos , Especificidade de Órgãos , Mapeamento de Interação de Proteínas
11.
PLoS Comput Biol ; 16(4): e1007780, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32298259

RESUMO

Metabolism plays an essential role in cell fate decisions. However, the methods used for metabolic characterization and for finding potential metabolic regulators are still based on characterizing cellular metabolic steady-state which is dependent on the extracellular environment. In this work, we hypothesized that the response dynamics of intracellular metabolic pools to extracellular stimuli is controlled in a cell type-specific manner. We applied principles of process dynamics and control to human induced pluripotent stem cells (hiPSC) and human neural stem cells (hNSC) subjected to a sudden extracellular glutamine step. The fold-changes of steady-states and the transient profiles of metabolic pools revealed that dynamic responses were reproducible and cell type-specific. Importantly, many amino acids had conserved dynamics and readjusted their steady state concentration in response to the increased glutamine influx. Overall, we propose a novel methodology for systematic metabolic characterization and identification of potential metabolic regulators.


Assuntos
Células-Tronco Pluripotentes Induzidas , Redes e Vias Metabólicas/fisiologia , Células-Tronco Neurais , Reatores Biológicos , Células Cultivadas , Biologia Computacional , Espaço Extracelular/química , Espaço Extracelular/metabolismo , Glutamina/metabolismo , Glutamina/farmacologia , Humanos , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Pluripotentes Induzidas/efeitos dos fármacos , Células-Tronco Pluripotentes Induzidas/metabolismo , Células-Tronco Neurais/citologia , Células-Tronco Neurais/efeitos dos fármacos , Células-Tronco Neurais/metabolismo
12.
J Cancer Res Clin Oncol ; 146(7): 1647-1658, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32335720

RESUMO

BACKGROUND: Additional prognostic factors and personalized therapeutic alternatives for vulvar squamous cell carcinoma (VSCC), especially for advanced stages with poor prognosis, are urgently needed. OBJECTIVES: To review and assess literature regarding underlying molecular mechanisms of VSCC target therapeutic and prognostic approaches. METHODS: We performed a narrative literature review from the inception of the database up to January 2020 limited to English language, organizing knowledge in five main fields: extracellular and intracellular cell cycle deregulation, tumor immune microenvironment, tumor angiogenesis and hormones. RESULTS: EGFR immunohistochemical overexpression/gene amplification, representing early events in VSCC carcinogenesis, have been correlated with a worse prognosis and led to inclusion of erlotinib in cancer guidelines. p16 expression and HPV positivity are linked to a better prognosis, while p53 overexpression is linked to a worse prognosis; thus, biomarkers could help tailoring conventional treatment and follow-up. The implications of PD-L1 positivity in reference to HPV status and prognosis are still not clear, even though pembrolizumab is part of available systemic therapies. The role of tumor angiogenesis emerges through data on microvessel density, immunohistochemical VEGF staining and evaluation of serum VEGF concentrations. Few data exist on hormonal receptor expression, even though hormonal therapy showed great manageability. CONCLUSIONS: We suggest adding p16, p53 and HPV status to routine hystopathological examination of vulvar biopsies or surgical specimens. Predictive biomarkers for anti-EGFR and anti-PD-1/PD-L1 drugs are needed. Enough preclinical data supporting anti-angiogenic target therapies in clinical trials are existing. Hormonal receptor expression deserves further investigation.


Assuntos
Biomarcadores Tumorais , Carcinoma de Células Escamosas/etiologia , Carcinoma de Células Escamosas/metabolismo , Regulação Neoplásica da Expressão Gênica , Transdução de Sinais , Neoplasias Vulvares/etiologia , Neoplasias Vulvares/metabolismo , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/patologia , Ciclo Celular/genética , Tomada de Decisão Clínica , Suscetibilidade a Doenças , Espaço Extracelular/metabolismo , Feminino , Humanos , Espaço Intracelular/metabolismo , Terapia de Alvo Molecular , Neovascularização Patológica/genética , Neovascularização Patológica/imunologia , Neovascularização Patológica/metabolismo , Microambiente Tumoral/efeitos dos fármacos , Microambiente Tumoral/genética , Microambiente Tumoral/imunologia , Neoplasias Vulvares/tratamento farmacológico , Neoplasias Vulvares/patologia
13.
PLoS One ; 15(4): e0230903, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32267858

RESUMO

Magnetic resonance electrical properties tomography (MREPT) uses the B1 mapping technique to provide the high-frequency conductivity distribution at Larmor frequency that simultaneously reflects the intracellular and extracellular effects. In biological tissues, the electrical conductivity can be described as the concentration and mobility of charge carriers. For the water molecule diffusivity, diffusion weighted imaging (DWI) measures the random Brownian motion of water molecules within biological tissues. The DWI data can quantitatively access the mobility of microscopic water molecules within biological tissues. By measuring multi-b-value DWI data and the recovered high-frequency conductivity at Larmor frequency, we propose a new method to decompose the conductivity into the total ion concentration and mobility in the extracellular space (ECS) within a routinely applicable MR scan time. Using the measured multi-b-value DWI data, a constrained compartment model is designed to estimate the extracellular volume fraction and extracellular mean diffusivity. With the extracted extracellular volume fraction and water molecule diffusivity, we directly reconstruct the low-frequency electrical properties including the extracellular mean conductivity and extracellular conductivity tensor. To demonstrate the proposed method by comparing the ion concentration and the ion mobility, we conducted human experiments for the proposed low-frequency conductivity imaging. Human experiments verify that the proposed method can recover the low-frequency electrical properties using a conventional MRI scanner.


Assuntos
Imagem de Difusão por Ressonância Magnética , Condutividade Elétrica , Espaço Extracelular/diagnóstico por imagem , Espaço Extracelular/metabolismo , Humanos , Processamento de Imagem Assistida por Computador
14.
Mutat Res ; 849: 503128, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-32087849

RESUMO

A physiological decrease in extracellular pH (pHe) alters the efficiency of DNA repair and increases formation of DNA double-strand breaks (DSBs). Whether this could translate into genetic instability and variations, was investigated using the TK6 cell model, in which positive selection of the TK1 gene loss-of-function mutations can be achieved from resistance to trifluorothymidine. Cell exposure to suboptimal pH (down to 6.9) for 3 weeks resulted in the 100 % frequency of a stronger frameshift mutation that has spread to both TK1 alleles, whereas weaker frameshift mutations within the 3'exon were eliminated during the selection. Suboptimal pHe values were also found to alter the proportion of the TK1 splicing variant expressed as percent spliced in index values and promote selection of truncated exons as well as intron retention. Although recovery at pH 7.4 did not reverse the selected frameshift mutation, reversal of splice variants and exon truncation towards control values were observed. Hence, suboptimal pHe can induce a combination of mutational events and splicing alterations within the same gene in the resistant clones. This model of positive selection for loss-of-function clearly demonstrates that suboptimal pHe may confer a similar growth advantage when such instability occurs within tumor suppressor genes.


Assuntos
Processamento Alternativo , Mutação da Fase de Leitura , Linfócitos/metabolismo , Modelos Genéticos , Mutagênese , Timidina Quinase/genética , Antimetabólitos/farmacologia , Linhagem Celular Tumoral , DNA/genética , DNA/metabolismo , Quebras de DNA de Cadeia Dupla , Reparo do DNA/efeitos dos fármacos , Éxons , Espaço Extracelular/química , Espaço Extracelular/metabolismo , Humanos , Concentração de Íons de Hidrogênio , Íntrons , Linfócitos/citologia , Linfócitos/efeitos dos fármacos , Timidina Quinase/metabolismo , Trifluridina/farmacologia
15.
Nat Commun ; 11(1): 758, 2020 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-32029728

RESUMO

We test the hypothesis that the frequency and cost of extracellular proteins produced by bacteria, which often depend on cooperative processes, vary with habitat structure and community diversity. The integration of the environmental distribution of bacteria (using 16S datasets) and their genomes shows that bacteria living in more structured habitats encode more extracellular proteins. In contrast, the effect of community diversity depends on protein function: it's positive for proteins implicated in antagonistic interactions and negative for those involved in nutrient acquisition. Extracellular proteins are costly and endure stronger selective pressure for low cost and for low diffusivity in less structured habitats and in more diverse communities. Finally, Bacteria found in multiple types of habitats, including host-associated generalists, encode more extracellular proteins than niche-restricted bacteria. These results show that ecological variables, notably habitat structure and community diversity, shape the evolution of the repertoires of genes encoding extracellular proteins and thus affect the ability of bacteria to manipulate their environment.


Assuntos
Bactérias/metabolismo , Proteínas de Bactérias/metabolismo , Microbiota/fisiologia , Bactérias/genética , Proteínas de Bactérias/genética , Biodiversidade , Ecossistema , Espaço Extracelular/metabolismo , Genes Bacterianos , Microbiota/genética , Modelos Biológicos , Filogenia , RNA Bacteriano/genética , RNA Ribossômico 16S/genética
16.
PLoS One ; 15(1): e0228093, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31971961

RESUMO

Multiple organ dysfunction induced by sepsis often involves kidney injury. Extracellular histones released in response to damage-associated molecular patterns are known to facilitate sepsis-induced organ dysfunction. Recombinant human soluble thrombomodulin (rhTM) and its lectin-like domain (D1) exert anti-inflammatory effects and neutralize damage-associated molecular patterns. However, the effects of rhTM and D1 on extracellular histone H3 levels and kidney injury remain poorly understood. Our purpose was to investigate the association between extracellular histone H3 levels and kidney injury, and to clarify the effects of rhTM and D1 on extracellular histone H3 levels, kidney injury, and survival in sepsis-induced rats. Rats in whom sepsis was induced via cecal ligation and puncture were used in this study. Histone H3 levels, histopathology of the kidneys, and the survival rate of rats at 24 h after cecal ligation and puncture were investigated. Histone H3 levels increased over time following cecal ligation and puncture. Histopathological analyses indicated that the distribution of degeneration foci among tubular epithelial cells of the kidney and levels of histone H3 increased simultaneously. Administration of rhTM and D1 significantly reduced histone H3 levels compared with that in the vehicle-treated group and improved kidney injury. The survival rates of rats in rhTM- and D1-treated groups were significantly higher than that in the vehicle-treated group. The results of this study indicated that rhTM and its D1 similarly reduce elevated histone H3 levels, thereby reducing acute kidney injury. Our findings also proposed that rhTM and D1 show potential as new treatment strategies for sepsis combined with acute kidney injury.


Assuntos
Espaço Extracelular/metabolismo , Histonas/metabolismo , Rim/patologia , Proteínas Recombinantes/uso terapêutico , Sepse/tratamento farmacológico , Trombomodulina/uso terapêutico , Animais , Ceco/patologia , Creatinina/sangue , Histonas/sangue , Humanos , Rim/efeitos dos fármacos , Ligadura , Masculino , Domínios Proteicos , Punções , Ratos Wistar , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/farmacologia , Sepse/sangue , Análise de Sobrevida , Trombomodulina/administração & dosagem , Trombomodulina/química
17.
Cancer Lett ; 473: 90-97, 2020 03 31.
Artigo em Inglês | MEDLINE | ID: mdl-31904485

RESUMO

Triple negative breast cancer (TNBC) is a breast cancer subtype which is particularly aggressive and invasive. The treatment of TNBC has been limited due to the lack of well-defined molecular targets. Exosomes are nano-sized extracellular vesicles that are released from virtually all cell types into the extracellular space. Due to their endocytic origin, exosomes carry valuable information from their cells of origin. Exosomes were first thought to serve as "garbage disposals" that eliminate unwanted cellular components. Later, they were found to be involved in the pathology of many diseases including cancer. Despite their established roles in multiple diseases, only a small number of studies have focused on the role of exosomes in TNBC. In this review, we outline the roles of exosomes in cancer progression, metastasis and drug resistance in this breast cancer subtype. We then further illustrate the potential roles of exosomes as diagnostic tools, therapeutic targets and delivery systems.


Assuntos
Antineoplásicos/farmacologia , Biomarcadores Tumorais/metabolismo , Sistemas de Liberação de Medicamentos , Exossomos/metabolismo , Neoplasias de Mama Triplo Negativas/patologia , Antineoplásicos/uso terapêutico , Biomarcadores Tumorais/antagonistas & inibidores , Progressão da Doença , Resistencia a Medicamentos Antineoplásicos , Exossomos/efeitos dos fármacos , Espaço Extracelular/metabolismo , Feminino , Humanos , Metástase Neoplásica/patologia , Neoplasias de Mama Triplo Negativas/diagnóstico , Neoplasias de Mama Triplo Negativas/tratamento farmacológico
18.
Redox Biol ; 28: 101337, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31622846

RESUMO

Cellular senescence may contribute to aging and age-related diseases and senolytic drugs that selectively kill senescent cells may delay aging and promote healthspan. More recently, several categories of senolytics have been established, namely HSP90 inhibitors, Bcl-2 family inhibitors and natural compounds such as quercetin and fisetin. However, senolytic and senostatic potential of nanoparticles and surface-modified nanoparticles has never been addressed. In the present study, quercetin surface functionalized Fe3O4 nanoparticles (MNPQ) were synthesized and their senolytic and senostatic activity was evaluated during oxidative stress-induced senescence in human fibroblasts in vitro. MNPQ promoted AMPK activity that was accompanied by non-apoptotic cell death and decreased number of stress-induced senescent cells (senolytic action) and the suppression of senescence-associated proinflammatory response (decreased levels of secreted IL-8 and IFN-ß, senostatic action). In summary, we have shown for the first time that MNPQ may be considered as promising candidates for senolytic- and senostatic-based anti-aging therapies.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Compostos Férricos , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Nanopartículas , Oxidantes/farmacologia , Quercetina/metabolismo , Apoptose , Biomarcadores , Células Cultivadas , Senescência Celular , Espaço Extracelular/metabolismo , Compostos Férricos/química , Compostos Férricos/metabolismo , Humanos , Peróxido de Hidrogênio/metabolismo , Concentração de Íons de Hidrogênio , Imunofenotipagem , Modelos Biológicos , Nanopartículas/química , Nanopartículas/metabolismo , Estresse Oxidativo , Quercetina/química
19.
Dev Cell ; 52(1): 104-117.e5, 2020 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-31866204

RESUMO

Ephrins can elicit either contact-mediated cell-cell adhesion or repulsion, depending on the efficiency of the removal of their ligand-receptor complexes from the cell surface, thus controlling tissue morphogenesis and oncogenic development. However, the dynamic of the turnover of newly assembled ephrin-Eph complexes during cell-cell interactions remains mostly unexplored. Here, we show that ephrin-A1-EphA2 complexes are locally formed at the tip of the filopodia, at cell-to-cell contacts. Clusters of ephrin-A1 from donor cells surf on filopodia associated to EphA2-bearing subdomains of acceptor cells. Full-length ephrin-A1 is transferred to acceptor cells by trans-endocytosis through a proteolysis-independent mechanism. Trans-endocytosed ephrin-A1 bound to its receptor enables signaling to be emitted from endo-lysosomes of acceptor cells. Localized trans-endocytosis of ephrin-A1 sustains contact-mediated repulsion on cancer cells. Our results uncover the essential role played by local concentration at the tip of filopodia and the trans-endocytosis of full-length ephrin to maintain long-lasting ephrin signaling.


Assuntos
Comunicação Celular , Membrana Celular/metabolismo , Endocitose , Efrina-A1/metabolismo , Efrina-A2/metabolismo , Pseudópodes/fisiologia , Adesão Celular , Efrina-A1/genética , Efrina-A2/genética , Espaço Extracelular/metabolismo , Humanos , Ligação Proteica , Transporte Proteico , Proteólise , Transdução de Sinais
20.
Sci Adv ; 5(12): eaaw3851, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31840053

RESUMO

Efforts to decipher chronic lung disease and to reconstitute functional lung tissue through regenerative medicine have been hampered by an incomplete understanding of cell-cell interactions governing tissue homeostasis. Because the structure of mammalian lungs is highly conserved at the histologic level, we hypothesized that there are evolutionarily conserved homeostatic mechanisms that keep the fine architecture of the lung in balance. We have leveraged single-cell RNA sequencing techniques to identify conserved patterns of cell-cell cross-talk in adult mammalian lungs, analyzing mouse, rat, pig, and human pulmonary tissues. Specific stereotyped functional roles for each cell type in the distal lung are observed, with alveolar type I cells having a major role in the regulation of tissue homeostasis. This paper provides a systems-level portrait of signaling between alveolar cell populations. These methods may be applicable to other organs, providing a roadmap for identifying key pathways governing pathophysiology and informing regenerative efforts.


Assuntos
Conectoma , Pulmão/citologia , Mamíferos/metabolismo , Análise de Célula Única , Animais , Linhagem Celular , Espaço Extracelular/metabolismo , Genes , Homeostase , Humanos , Ligantes , Alvéolos Pulmonares/metabolismo , Receptores de Superfície Celular/metabolismo , Semaforinas/metabolismo , Transdução de Sinais , Especificidade da Espécie , Fator A de Crescimento do Endotélio Vascular/metabolismo
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