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1.
Nat Immunol ; 23(2): 287-302, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35105987

RESUMO

The volume-regulated anion channel (VRAC) is formed by LRRC8 proteins and is responsible for the regulatory volume decrease (RVD) after hypotonic cell swelling. Besides chloride, VRAC transports other molecules, for example, immunomodulatory cyclic dinucleotides (CDNs) including 2'3'cGAMP. Here, we identify LRRC8C as a critical component of VRAC in T cells, where its deletion abolishes VRAC currents and RVD. T cells of Lrrc8c-/- mice have increased cell cycle progression, proliferation, survival, Ca2+ influx and cytokine production-a phenotype associated with downmodulation of p53 signaling. Mechanistically, LRRC8C mediates the transport of 2'3'cGAMP in T cells, resulting in STING and p53 activation. Inhibition of STING recapitulates the phenotype of LRRC8C-deficient T cells, whereas overexpression of p53 inhibits their enhanced T cell function. Lrrc8c-/- mice have exacerbated T cell-dependent immune responses, including immunity to influenza A virus infection and experimental autoimmune encephalomyelitis. Our results identify cGAMP uptake through LRRC8C and STING-p53 signaling as a new inhibitory signaling pathway in T cells and adaptive immunity.


Assuntos
Ânions/metabolismo , Fosfatos de Dinucleosídeos/metabolismo , Canais Iônicos/metabolismo , Proteínas de Membrana/metabolismo , Linfócitos T/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Animais , Cálcio/metabolismo , Feminino , Camundongos , Camundongos Endogâmicos C57BL , Nucleotídeos Cíclicos/metabolismo , Transdução de Sinais/fisiologia
3.
Nature ; 627(8004): 586-593, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38355797

RESUMO

Over half of hepatocellular carcinoma (HCC) cases diagnosed worldwide are in China1-3. However, whole-genome analysis of hepatitis B virus (HBV)-associated HCC in Chinese individuals is limited4-8, with current analyses of HCC mainly from non-HBV-enriched populations9,10. Here we initiated the Chinese Liver Cancer Atlas (CLCA) project and performed deep whole-genome sequencing (average depth, 120×) of 494 HCC tumours. We identified 6 coding and 28 non-coding previously undescribed driver candidates. Five previously undescribed mutational signatures were found, including aristolochic-acid-associated indel and doublet base signatures, and a single-base-substitution signature that we termed SBS_H8. Pentanucleotide context analysis and experimental validation confirmed that SBS_H8 was distinct to the aristolochic-acid-associated SBS22. Notably, HBV integrations could take the form of extrachromosomal circular DNA, resulting in elevated copy numbers and gene expression. Our high-depth data also enabled us to characterize subclonal clustered alterations, including chromothripsis, chromoplexy and kataegis, suggesting that these catastrophic events could also occur in late stages of hepatocarcinogenesis. Pathway analysis of all classes of alterations further linked non-coding mutations to dysregulation of liver metabolism. Finally, we performed in vitro and in vivo assays to show that fibrinogen alpha chain (FGA), determined as both a candidate coding and non-coding driver, regulates HCC progression and metastasis. Our CLCA study depicts a detailed genomic landscape and evolutionary history of HCC in Chinese individuals, providing important clinical implications.


Assuntos
Carcinoma Hepatocelular , Genoma Humano , Sequenciamento de Nucleotídeos em Larga Escala , Neoplasias Hepáticas , Mutação , Sequenciamento Completo do Genoma , Humanos , Ácidos Aristolóquicos/metabolismo , Carcinogênese , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/virologia , China , Cromotripsia , Progressão da Doença , DNA Circular/genética , População do Leste Asiático/genética , Evolução Molecular , Genoma Humano/genética , Vírus da Hepatite B/genética , Mutação INDEL/genética , Fígado/metabolismo , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/virologia , Mutação/genética , Metástase Neoplásica/genética , Fases de Leitura Aberta/genética , Reprodutibilidade dos Testes
4.
Nature ; 618(7967): 1017-1023, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37316672

RESUMO

The discovery and application of genome editing introduced a new era of plant breeding by giving researchers efficient tools for the precise engineering of crop genomes1. Here we demonstrate the power of genome editing for engineering broad-spectrum disease resistance in rice (Oryza sativa). We first isolated a lesion mimic mutant (LMM) from a mutagenized rice population. We then demonstrated that a 29-base-pair deletion in a gene we named RESISTANCE TO BLAST1 (RBL1) caused broad-spectrum disease resistance and showed that this mutation caused an approximately 20-fold reduction in yield. RBL1 encodes a cytidine diphosphate diacylglycerol synthase that is required for phospholipid biosynthesis2. Mutation of RBL1 results in reduced levels of phosphatidylinositol and its derivative phosphatidylinositol 4,5-bisphosphate (PtdIns(4,5)P2). In rice, PtdIns(4,5)P2 is enriched in cellular structures that are specifically associated with effector secretion and fungal infection, suggesting that it has a role as a disease-susceptibility factor3. By using targeted genome editing, we obtained an allele of RBL1, named RBL1Δ12, which confers broad-spectrum disease resistance but does not decrease yield in a model rice variety, as assessed in small-scale field trials. Our study has demonstrated the benefits of editing an LMM gene, a strategy relevant to diverse LMM genes and crops.


Assuntos
Diacilglicerol Colinofosfotransferase , Resistência à Doença , Edição de Genes , Oryza , Melhoramento Vegetal , Doenças das Plantas , Resistência à Doença/genética , Edição de Genes/métodos , Genoma de Planta/genética , Oryza/enzimologia , Oryza/genética , Oryza/microbiologia , Fosfatidilinositóis/metabolismo , Melhoramento Vegetal/métodos , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Alelos , Fosfatidilinositol 4,5-Difosfato/metabolismo , Diacilglicerol Colinofosfotransferase/genética , Diacilglicerol Colinofosfotransferase/metabolismo
5.
Genes Dev ; 35(15-16): 1093-1108, 2021 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-34266887

RESUMO

Abnormal numerical and structural chromosome content is frequently found in human cancer. To test the role of aneuploidy in tumor initiation and progression, we generated mice with random aneuploidies by transient induction of polo-like kinase 4 (Plk4), a master regulator of centrosome number. Short-term chromosome instability (CIN) from transient Plk4 induction resulted in formation of aggressive T-cell lymphomas in mice with heterozygous inactivation of one p53 allele and accelerated tumor development in the absence of p53. Transient CIN increased the frequency of lymphoma-initiating cells with a specific karyotype profile, including trisomy of chromosomes 4, 5, 14, and 15 occurring early in tumorigenesis. Tumor development in mice with chronic CIN induced by an independent mechanism (through inactivation of the spindle assembly checkpoint) gradually trended toward a similar karyotypic profile, as determined by single-cell whole-genome DNA sequencing. Overall, we show how transient CIN generates cells with random aneuploidies from which ones that acquire a karyotype with specific chromosome gains are sufficient to drive cancer formation, and that distinct CIN mechanisms can lead to similar karyotypic cancer-causing outcomes.


Assuntos
Aneuploidia , Instabilidade Cromossômica , Animais , Transformação Celular Neoplásica/genética , Centrossomo , Instabilidade Cromossômica/genética , Evolução Clonal , Instabilidade Genômica/genética , Camundongos
6.
Nat Immunol ; 17(1): 95-103, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26523864

RESUMO

Aerobic glycolysis regulates T cell function. However, whether and how primary cancer alters T cell glycolytic metabolism and affects tumor immunity in cancer patients remains a question. Here we found that ovarian cancers imposed glucose restriction on T cells and dampened their function via maintaining high expression of microRNAs miR-101 and miR-26a, which constrained expression of the methyltransferase EZH2. EZH2 activated the Notch pathway by suppressing Notch repressors Numb and Fbxw7 via trimethylation of histone H3 at Lys27 and, consequently, stimulated T cell polyfunctional cytokine expression and promoted their survival via Bcl-2 signaling. Moreover, small hairpin RNA-mediated knockdown of human EZH2 in T cells elicited poor antitumor immunity. EZH2(+)CD8(+) T cells were associated with improved survival in patients. Together, these data unveil a metabolic target and mechanism of cancer immune evasion.


Assuntos
Regulação Neoplásica da Expressão Gênica/imunologia , MicroRNAs , Neoplasias/imunologia , Complexo Repressor Polycomb 2/imunologia , Linfócitos T/imunologia , Evasão Tumoral/imunologia , Animais , Separação Celular , Imunoprecipitação da Cromatina , Proteína Potenciadora do Homólogo 2 de Zeste , Feminino , Citometria de Fluxo , Imunofluorescência , Glicólise , Humanos , Immunoblotting , Melanoma Experimental/imunologia , Camundongos Endogâmicos C57BL , Neoplasias Ovarianas/imunologia , Reação em Cadeia da Polimerase em Tempo Real , Análise Serial de Tecidos , Transfecção
7.
Plant Cell ; 2024 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-39422240

RESUMO

Plants bearing double flowers have long been cultivated as ornamental plants. Hose-in-hose flowers, bearing 2-whorled corolla tubes in whorls 1 and 2, are uncommon but recur in Sinningia (Gesnerioideae, Gesneriaceae). In this study, we selected 15 hose-in-hose cultivars as materials to explore the underlying molecular and genetic mechanisms of this floral architecture. We found that they originated from different hybridization events within the Dircaea clade. Three B-class MADS-box genes were globally expressed in all floral whorls, but only GLOBOSA1 (GLO1) has accumulated a dominant mutation, i.e., the insertion of a hAT-like miniature inverted-repeat transposable element (MITE) into its promoter, that co-segregated with the hose-in-hose phenotype. In addition, all 15 hose-in-hose cultivars contained the same dominant GLO1 allele. Transient gene expression assays confirmed the role of this MITE insertion in up-regulating the promoter activity of GLO1 by providing several cis-regulatory elements. Genetic transformation in heterologous Chirita pumila (Didymocarpoideae, Gesneriaceae) verified that this dominant GLO1 allele is sufficient to confer the hose-in-hose phenotype. We further demonstrated that both the GLO1 allele and the hAT-like MITE descended from wild S. cardinalis with single flowers. This study highlights the significance of wide hybridization in frequent gains of the dominant GLO1 allele and thereafter repeated occurrence of hose-in-hose flowers in Sinningia.

8.
Proc Natl Acad Sci U S A ; 121(10): e2320859121, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38412130

RESUMO

Well-controlled repair mechanisms are involved in the maintenance of genomic stability, and their failure can precipitate DNA abnormalities and elevate tumor risk. In addition, the tumor microenvironment, enriched with factors inducing oxidative stress and affecting cell cycle checkpoints, intensifies DNA damage when repair pathways falter. Recent research has unveiled associations between certain bacteria, including Mycoplasmas, and various cancers, and the causative mechanism(s) are under active investigation. We previously showed that Mycoplasma fermentans DnaK, an HSP70 family chaperone protein, hampers the activity of proteins like PARP1 and p53, crucial for genomic integrity. Moreover, our analysis of its interactome in human cancer cell lines revealed DnaK's engagement with several components of DNA-repair machinery. Finally, in vivo experiments performed in our laboratory using a DnaK knock-in mouse model generated by our group demonstrated that DnaK exposure led to increased DNA copy number variants, indicative of genomic instability. We present here evidence that expression of DnaK is linked to increased i) incidence of tumors in vivo upon exposure to urethane, a DNA damaging agent; ii) spontaneous DNA damage ex vivo; and iii) expression of proinflammatory cytokines ex vivo, variations in reactive oxygen species levels, and increased ß-galactosidase activity across tissues. Moreover, DnaK was associated with increased centromeric instability. Overall, these findings highlight the significance of Mycoplasma DnaK in the etiology of cancer and other genetic disorders providing a promising target for prevention, diagnostics, and therapeutics.


Assuntos
Proteínas de Bactérias , Proteínas de Choque Térmico HSP70 , Mycoplasma , Neoplasias , Animais , Humanos , Camundongos , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , DNA , Dano ao DNA , Proteínas de Escherichia coli/metabolismo , Proteínas de Choque Térmico HSP70/genética , Proteínas de Choque Térmico HSP70/metabolismo , Mycoplasma/fisiologia , Neoplasias/metabolismo , Neoplasias/microbiologia , Neoplasias/patologia , Microambiente Tumoral
9.
Nat Methods ; 20(7): 1010-1020, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37202537

RESUMO

The Cell Tracking Challenge is an ongoing benchmarking initiative that has become a reference in cell segmentation and tracking algorithm development. Here, we present a significant number of improvements introduced in the challenge since our 2017 report. These include the creation of a new segmentation-only benchmark, the enrichment of the dataset repository with new datasets that increase its diversity and complexity, and the creation of a silver standard reference corpus based on the most competitive results, which will be of particular interest for data-hungry deep learning-based strategies. Furthermore, we present the up-to-date cell segmentation and tracking leaderboards, an in-depth analysis of the relationship between the performance of the state-of-the-art methods and the properties of the datasets and annotations, and two novel, insightful studies about the generalizability and the reusability of top-performing methods. These studies provide critical practical conclusions for both developers and users of traditional and machine learning-based cell segmentation and tracking algorithms.


Assuntos
Benchmarking , Rastreamento de Células , Rastreamento de Células/métodos , Aprendizado de Máquina , Algoritmos
10.
Plant Cell ; 35(8): 2799-2820, 2023 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-37132634

RESUMO

Actinomorphic flowers usually orient vertically (relative to the horizon) and possess symmetric nectar guides, while zygomorphic flowers often face horizontally and have asymmetric nectar guides, indicating that floral symmetry, floral orientation, and nectar guide patterning are correlated. The origin of floral zygomorphy is dependent on the dorsoventrally asymmetric expression of CYCLOIDEA (CYC)-like genes. However, how horizontal orientation and asymmetric nectar guides are achieved remains poorly understood. Here, we selected Chirita pumila (Gesneriaceae) as a model plant to explore the molecular bases for these traits. By analyzing gene expression patterns, protein-DNA and protein-protein interactions, and encoded protein functions, we identified multiple roles and functional divergence of 2 CYC-like genes, i.e. CpCYC1 and CpCYC2, in controlling floral symmetry, floral orientation, and nectar guide patterning. CpCYC1 positively regulates its own expression, whereas CpCYC2 does not regulate itself. In addition, CpCYC2 upregulates CpCYC1, while CpCYC1 downregulates CpCYC2. This asymmetric auto-regulation and cross-regulation mechanism might explain the high expression levels of only 1 of these genes. We show that CpCYC1 and CpCYC2 determine asymmetric nectar guide formation, likely by directly repressing the flavonoid synthesis-related gene CpF3'5'H. We further suggest that CYC-like genes play multiple conserved roles in Gesneriaceae. These findings shed light on the repeated origins of zygomorphic flowers in angiosperms.


Assuntos
Magnoliopsida , Néctar de Plantas , Néctar de Plantas/genética , Filogenia , Magnoliopsida/genética , Flores/genética , Genes de Plantas/genética
11.
PLoS Biol ; 21(5): e3002062, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37134086

RESUMO

Members of the gasdermin (GSDM) family are pore-forming effectors that cause membrane permeabilization and pyroptosis, a lytic proinflammatory type of cell death. To reveal the functional evolution of GSDM-mediated pyroptosis at the transition from invertebrates to vertebrates, we conducted functional characterization of amphioxus GSDME (BbGSDME) and found that it can be cleaved by distinct caspase homologs, yielding the N253 and N304 termini with distinct functions. The N253 fragment binds to cell membrane, triggers pyroptosis, and inhibits bacterial growth, while the N304 performs negative regulation of N253-mediated cell death. Moreover, BbGSDME is associated with bacteria-induced tissue necrosis and transcriptionally regulated by BbIRF1/8 in amphioxus. Interestingly, several amino acids that are evolutionarily conserved were found to be important for the function of both BbGSDME and HsGSDME, shedding new lights on the functional regulation of GSDM-mediated inflammation.


Assuntos
Anfioxos , Piroptose , Animais , Piroptose/fisiologia , Anfioxos/genética , Anfioxos/metabolismo , Morte Celular , Necrose , Caspase 3/metabolismo
12.
Nucleic Acids Res ; 52(D1): D972-D979, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-37831083

RESUMO

Leveraging genetics insights to promote drug repurposing has become a promising and active strategy in pharmacology. Indeed, among the 50 drugs approved by FDA in 2021, two-thirds have genetically supported evidence. In this regard, the increasing amount of widely available genome-wide association studies (GWAS) datasets have provided substantial opportunities for drug repurposing based on genetics discoveries. Here, we developed PharmGWAS, a comprehensive knowledgebase designed to identify candidate drugs through the integration of GWAS data. PharmGWAS focuses on novel connections between diseases and small-molecule compounds derived using a reverse relationship between the genetically-regulated expression signature and the drug-induced signature. Specifically, we collected and processed 1929 GWAS datasets across a diverse spectrum of diseases and 724 485 perturbation signatures pertaining to a substantial 33609 molecular compounds. To obtain reliable and robust predictions for the reverse connections, we implemented six distinct connectivity methods. In the current version, PharmGWAS deposits a total of 740 227 genetically-informed disease-drug pairs derived from drug-perturbation signatures, presenting a valuable and comprehensive catalog. Further equipped with its user-friendly web design, PharmGWAS is expected to greatly aid the discovery of novel drugs, the exploration of drug combination therapies and the identification of drug resistance or side effects. PharmGWAS is available at https://ngdc.cncb.ac.cn/pharmgwas.


Assuntos
Bases de Dados de Produtos Farmacêuticos , Reposicionamento de Medicamentos , Estudo de Associação Genômica Ampla , Reposicionamento de Medicamentos/métodos , Estudo de Associação Genômica Ampla/métodos
13.
Nano Lett ; 24(8): 2661-2670, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38345313

RESUMO

Nanomaterial-assisted chemodynamic therapy (CDT) has received considerable attention in recent years. It outperforms other modalities by its distinctive reactive oxygen species (ROS) generation through a nonexogenous stimulant. However, CDT is limited by the insufficient content of endogenous hydrogen peroxide (H2O2). Herein, a biodegradable MnS@HA-DOX nanocluster (MnS@HA-DOX NC) was constructed by in situ biomineralization from hyaluronic acid, to enlarge the ROS cascade and boost Mn2+-based CDT. The acid-responsive NCs could quickly degrade after internalization into endo/lysosomes, releasing Mn2+, H2S gas, and anticancer drug doxorubicin (DOX). The Fenton-like reaction catalyzed by Mn2+ was amplified by both H2S and DOX, producing a mass of cytotoxic ·OH radicals. Through the combined action of gas therapy (GT), CDT, and chemotherapy, oxidative stress would be synergistically enhanced, inducing irreversible DNA damage and cell cycle arrest, eventually resulting in cancer cell apoptosis.


Assuntos
Peróxido de Hidrogênio , Neoplasias , Humanos , Espécies Reativas de Oxigênio , Peróxido de Hidrogênio/farmacologia , Doxorrubicina/farmacologia , Apoptose , Biomineralização , Gases , Linhagem Celular Tumoral , Microambiente Tumoral
14.
Am J Physiol Cell Physiol ; 326(6): C1563-C1572, 2024 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-38586879

RESUMO

Atherosclerosis is an inflammatory disease of blood vessels involving the immune system. Natural killer T (NKT) cells, as crucial components of the innate and acquired immune systems, play critical roles in the development of atherosclerosis. However, the mechanism and clinical relevance of NKT cells in early atherosclerosis are largely unclear. The study investigated the mechanism influencing NKT cell function in apoE deficiency-induced early atherosclerosis. Our findings demonstrated that there were higher populations of NKT cells and interferon-gamma (IFN-γ)-producing NKT cells in the peripheral blood of patients with hyperlipidemia and in the aorta, blood, spleen, and bone marrow of early atherosclerotic mice compared with the control groups. Moreover, we discovered that the infiltration of CD80+ macrophages and CD1d expression on CD80+ macrophages in atherosclerotic mice climbed remarkably. CD1d expression increased in CD80+ macrophages stimulated by oxidized low-density lipoprotein (ox-LDL) ex vivo and in vitro. Ex vivo coculture of macrophages with NKT cells revealed that ox-LDL-induced CD80+ macrophages presented lipid antigen α-Galcer (alpha-galactosylceramide) to NKT cells via CD1d, enabling NKT cells to express more IFN-γ. Furthermore, a greater proportion of CD1d+ monocytes and CD1d+CD80+ monocytes were found in peripheral blood of hyperlipidemic patients compared with that of healthy donors. Positive correlations were found between CD1d+CD80+ monocytes and NKT cells or IFN-γ+ NKT cells in hyperlipidemic patients. Our findings illustrated that CD80+ macrophages stimulated NKT cells to secrete IFN-γ via CD1d-presenting α-Galcer, which may accelerate the progression of early atherosclerosis. Inhibiting lipid antigen presentation by CD80+ macrophages to NKT cells may be a promising immune target for the treatment of early atherosclerosis.NEW & NOTEWORTHY This work proposed the ox-LDL-CD80+ monocyte/macrophage-CD1d-NKT cell-IFN-γ axis in the progression of atherosclerosis. The proinflammatory IFN-γ+ NKT cells are closely related to CD1d+CD80+ monocytes in hyperlipidemic patients. Inhibiting CD80+ macrophages to present lipid antigens to NKT cells through CD1d blocking may be a new therapeutic target for atherosclerosis.


Assuntos
Antígenos CD1d , Aterosclerose , Antígeno B7-1 , Hiperlipidemias , Lipoproteínas LDL , Macrófagos , Células T Matadoras Naturais , Animais , Humanos , Células T Matadoras Naturais/imunologia , Células T Matadoras Naturais/metabolismo , Antígenos CD1d/metabolismo , Antígenos CD1d/imunologia , Antígenos CD1d/genética , Aterosclerose/imunologia , Aterosclerose/metabolismo , Aterosclerose/patologia , Hiperlipidemias/imunologia , Hiperlipidemias/metabolismo , Lipoproteínas LDL/imunologia , Lipoproteínas LDL/metabolismo , Macrófagos/imunologia , Macrófagos/metabolismo , Masculino , Camundongos , Antígeno B7-1/metabolismo , Antígeno B7-1/imunologia , Interferon gama/metabolismo , Interferon gama/imunologia , Camundongos Endogâmicos C57BL , Feminino , Pessoa de Meia-Idade
15.
J Cell Mol Med ; 28(8): e18217, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38520208

RESUMO

CircRNAs represent a new class of non-coding RNAs which show aberrant expression in diverse cancers, such as gastric cancer (GC). circSTRBP, for instance, is suggested to be overexpressed in GC cells and tissues. However, the biological role of circSTRBP in the progression of GC and the potential mechanisms have not been investigated. circSTRBP levels within GC cells and tissues were measured by RT-qPCR. The stability of circSTRBP was assessed by actinomycin D and Ribonuclease R treatment. Cell proliferation, migration, invasion and in vitro angiogenic abilities after circSTRBP knockdown were analysed through CCK-8 assay, transwell culture system and the tube formation assay. The interaction of circSTRBP with the predicted target microRNA (miRNA) was examined by RNA immunoprecipitation and luciferase reporter assays. Xenograft tumour model was established to evaluate the role of exosomal circSTRBP in the tumour formation of GC cells. circSTRBP was upregulated in GC cells and tissues, and there was an increased level of circSTRBP in GC-derived exosomes. circSTRBP in the exosomes enhanced GC cell growth and migration in vitro, which modulates E2F Transcription Factor 2 (E2F2) expression through targeting miR-1294 and miR-593-3p. Additionally, exosomal circSTRBP promoted the tumour growth of GC cells in the xenograft model. Exosomal circSTRBP is implicated in the progression of GC by modulating the activity of miR-1294/miR-593-3p/E2F2 axis.


Assuntos
MicroRNAs , Neoplasias Gástricas , Humanos , Animais , Neoplasias Gástricas/genética , Transformação Celular Neoplásica , MicroRNAs/genética , Bioensaio , Proliferação de Células/genética , Modelos Animais de Doenças , Linhagem Celular Tumoral , Fator de Transcrição E2F2
16.
Antimicrob Agents Chemother ; 68(1): e0119323, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38084952

RESUMO

The chromosomally encoded AmpC beta-lactamase is widely distributed throughout the Enterobacterales. When expressed at high levels through transient induction or stable de-repression, resistance to ceftriaxone, a commonly used antibiotic, can develop. Recent clinical guidance suggests, based on limited evidence, that resistance may be less likely to develop in Serratia marcescens compared to the better-studied Enterobacter cloacae and recommends that ceftriaxone may be used if the clinical isolate tests susceptible. We sought to generate additional data relevant to this recommendation. AmpC de-repression occurs predominantly because of mutation in the ampD peptidoglycan amidohydrolase. We find that, in contrast to E. cloacae, where deletion of ampD results in high-level ceftriaxone resistance (with ceftriaxone MIC = 96 µg/mL), in S. marcescens deletion of two amidohydrolases (ampD and amiD2) is necessary for AmpC de-repression, and the resulting ceftriaxone MIC is 1 µg/mL. Two mechanisms for this difference were identified. We find both a higher relative increase in ampC transcript level in E. cloacae ΔampD compared to S. marcescens ΔampDΔamiD2, as well as higher in vivo efficiency of ceftriaxone hydrolysis by the E. cloacae AmpC enzyme compared to the S. marcescens AmpC enzyme. We also observed higher relative levels of transient AmpC induction in E. cloacae vs S. marcescens when exposed to ceftriaxone. In time-kill curves, this difference translates into the survival of E. cloacae but not S. marcescens at clinically relevant ceftriaxone concentrations. In summary, our findings can explain the decreased propensity for on-treatment ceftriaxone resistance development in S. marcescens, thereby supporting recently issued clinical guidance.


Assuntos
Enterobacter cloacae , Serratia marcescens , Ceftriaxona/farmacologia , beta-Lactamases/genética , Antibacterianos/farmacologia , Proteínas de Bactérias/genética
17.
Gastroenterology ; 165(3): 746-761.e16, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37263311

RESUMO

BACKGROUND & AIMS: Liver fibrosis is an intrinsic wound-healing response to chronic injury and the major cause of liver-related morbidity and mortality worldwide. However, no effective diagnostic or therapeutic strategies are available, owing to its poorly characterized molecular etiology. We aimed to elucidate the mechanisms underlying liver fibrogenesis. METHODS: We performed a quantitative proteomic analysis of clinical fibrotic liver samples to identify dysregulated proteins. Further analyses were performed on the sera of 164 patients with liver fibrosis. Two fibrosis mouse models and several biochemical experiments were used to elucidate liver fibrogenesis. RESULTS: We identified cathepsin S (CTSS) up-regulation as a central node for extracellular matrix remodeling in the human fibrotic liver by proteomic screening. Increased serum CTSS levels efficiently predicted liver fibrosis, even at an early stage. Secreted CTSS cleaved collagen 18A1 at its C-terminus, releasing endostatin peptide, which directly bound to and activated hepatic stellate cells via integrin α5ß1 signaling, whereas genetic ablation of Ctss remarkably suppressed liver fibrogenesis via endostatin reduction in vivo. Further studies identified macrophages as the main source of hepatic CTSS, and splenectomy effectively attenuated macrophage infiltration and CTSS expression in the fibrotic liver. Pharmacologic inhibition of CTSS ameliorated liver fibrosis progression in the mouse models. CONCLUSIONS: CTSS functions as a novel profibrotic factor by remodeling extracellular matrix proteins and may represent a promising target for the diagnosis and treatment of liver fibrosis.


Assuntos
Endostatinas , Proteômica , Camundongos , Animais , Humanos , Endostatinas/metabolismo , Endostatinas/farmacologia , Fígado/metabolismo , Cirrose Hepática/metabolismo , Fibrose , Modelos Animais de Doenças , Células Estreladas do Fígado/metabolismo , Matriz Extracelular , Macrófagos/metabolismo
18.
Anal Chem ; 96(15): 5852-5859, 2024 04 16.
Artigo em Inglês | MEDLINE | ID: mdl-38556977

RESUMO

A multicolor electrochemiluminescence (ECL) biosensor based on a closed bipolar electrode (BPE) array was proposed for the rapid and intuitive analysis of three prostate cancer staging indicators. First, [Irpic-OMe], [Ir(ppy)2(acac)], and [Ru(bpy)3]2+ were applied as blue, green, and red ECL emitters, respectively, whose mixed ECL emission colors covered the whole visible region by varying the applied voltages. Afterward, we designed a simple Mg2+-dependent DNAzyme (MNAzyme)-driven tripedal DNA walker (TD walker) to release three output DNAs. Immediately after, three output DNAs were added to the cathodic reservoirs of the BPE for incubation. After that, we found that the emission colors from the anode of the BPE changed as a driving voltage of 8.0 V was applied, mainly due to changes in the interfacial potential and faradaic currents at the two poles of the BPE. Via optimization of the experimental parameters, cutoff values of such three indicators at different clinical stages could be identified instantly with the naked eye, and standard precision swatches with multiple indicators could be prepared. Finally, in order to precisely determine the prostate cancer stage, the multicolor ECL device was used for clinical analysis, and the resulting images were then compared with standard swatches, laying the way for accurate prostate cancer therapy.


Assuntos
Técnicas Biossensoriais , Neoplasias da Próstata , Masculino , Humanos , Medições Luminescentes/métodos , Fotometria , Neoplasias da Próstata/diagnóstico , Antígeno Prostático Específico , DNA , Técnicas Biossensoriais/métodos , Eletrodos , Técnicas Eletroquímicas/métodos
19.
Genome Res ; 31(1): 146-158, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33272935

RESUMO

As the most complex organ of the human body, the brain is composed of diverse regions, each consisting of distinct cell types and their respective cellular interactions. Human brain development involves a finely tuned cascade of interactive events. These include spatiotemporal gene expression changes and dynamic alterations in cell-type composition. However, our understanding of this process is still largely incomplete owing to the difficulty of brain spatiotemporal transcriptome collection. In this study, we developed a tensor-based approach to impute gene expression on a transcriptome-wide level. After rigorous computational benchmarking, we applied our approach to infer missing data points in the widely used BrainSpan resource and completed the entire grid of spatiotemporal transcriptomics. Next, we conducted deconvolutional analyses to comprehensively characterize major cell-type dynamics across the entire BrainSpan resource to estimate the cellular temporal changes and distinct neocortical areas across development. Moreover, integration of these results with GWAS summary statistics for 13 brain-associated traits revealed multiple novel trait-cell-type associations and trait-spatiotemporal relationships. In summary, our imputed BrainSpan transcriptomic data provide a valuable resource for the research community and our findings help further studies of the transcriptional and cellular dynamics of the human brain and related diseases.


Assuntos
Encefalopatias , Encéfalo , Perfilação da Expressão Gênica , Humanos , Fenótipo , Transcriptoma
20.
Small ; 20(25): e2309557, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38705855

RESUMO

This review focuses on the advanced design and optimization of nanostructured zinc-air batteries (ZABs), with the aim of boosting their energy storage and conversion capabilities. The findings show that ZABs favor porous nanostructures owing to their large surface area, and this enhances the battery capacity, catalytic activity, and life cycle. In addition, the nanomaterials improve the electrical conductivity, ion transport, and overall battery stability, which crucially reduces dendrite growth on the zinc anodes and improves cycle life and energy efficiency. To obtain a superior performance, the importance of controlling the operational conditions and using custom nanostructural designs, optimal electrode materials, and carefully adjusted electrolytes is highlighted. In conclusion, porous nanostructures and nanoscale materials significantly boost the energy density, longevity, and efficiency of Zn-air batteries. It is suggested that future research should focus on the fundamental design principles of these materials to further enhance the battery performance and drive sustainable energy solutions.

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