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1.
Cell ; 155(4): 793-806, 2013 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-24209618

RESUMO

The eukaryotic biological clock involves a negative transcription-translation feedback loop in which clock genes regulate their own transcription and that of output genes of metabolic significance. While around 10% of the liver transcriptome is rhythmic, only about a fifth is driven by de novo transcription, indicating mRNA processing is a major circadian component. Here, we report that inhibition of transmethylation reactions elongates the circadian period. RNA sequencing then reveals methylation inhibition causes widespread changes in the transcription of the RNA processing machinery, associated with m(6)A-RNA methylation. We identify m(6)A sites on many clock gene transcripts and show that specific inhibition of m(6)A methylation by silencing of the m(6)A methylase Mettl3 is sufficient to elicit circadian period elongation and RNA processing delay. Analysis of the circadian nucleocytoplasmic distribution of clock genes Per2 and Arntl then revealed an uncoupling between steady-state pre-mRNA and cytoplasmic mRNA rhythms when m(6)A methylation is inhibited.


Assuntos
Relógios Circadianos , Metiltransferases/metabolismo , Processamento Pós-Transcricional do RNA , RNA/metabolismo , Translocador Nuclear Receptor Aril Hidrocarboneto/metabolismo , Linhagem Celular , Linhagem Celular Tumoral , Técnicas de Silenciamento de Genes , Humanos , Metilação/efeitos dos fármacos , Metiltransferases/genética , Proteínas Circadianas Period/metabolismo , Tubercidina/farmacologia
2.
Proc Natl Acad Sci U S A ; 117(25): 14365-14375, 2020 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-32513690

RESUMO

Proper resolution of inflammation is vital for repair and restoration of homeostasis after tissue damage, and its dysregulation underlies various noncommunicable diseases, such as cardiovascular and metabolic diseases. Macrophages play diverse roles throughout initial inflammation, its resolution, and tissue repair. Differential metabolic reprogramming is reportedly required for induction and support of the various macrophage activation states. Here we show that a long noncoding RNA (lncRNA), lncFAO, contributes to inflammation resolution and tissue repair in mice by promoting fatty acid oxidation (FAO) in macrophages. lncFAO is induced late after lipopolysaccharide (LPS) stimulation of cultured macrophages and in Ly6Chi monocyte-derived macrophages in damaged tissue during the resolution and reparative phases. We found that lncFAO directly interacts with the HADHB subunit of mitochondrial trifunctional protein and activates FAO. lncFAO deletion impairs resolution of inflammation related to endotoxic shock and delays resolution of inflammation and tissue repair in a skin wound. These results demonstrate that by tuning mitochondrial metabolism, lncFAO acts as a node of immunometabolic control in macrophages during the resolution and repair phases of inflammation.


Assuntos
Ácidos Graxos/metabolismo , Inflamação/imunologia , Macrófagos/imunologia , Subunidade beta da Proteína Mitocondrial Trifuncional/genética , RNA Longo não Codificante/metabolismo , Animais , Modelos Animais de Doenças , Técnicas de Silenciamento de Genes , Humanos , Lipopolissacarídeos/imunologia , Ativação de Macrófagos/genética , Macrófagos/metabolismo , Masculino , Camundongos , Subunidade beta da Proteína Mitocondrial Trifuncional/metabolismo , Oxirredução , Cultura Primária de Células , RNA Longo não Codificante/genética , Pele/imunologia , Pele/lesões , Cicatrização/imunologia
3.
Int J Mol Sci ; 22(5)2021 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-33652591

RESUMO

Repressor element-1 (RE-1) or neural restrictive silencer element (NRSE) bound with a zinc finger transcription repressor, RE-1 silencing transcription factor (REST, also known as neural restrictive silencer factor, NRSF) has been identified as a fundamental repressor element in many genes, including neuronal genes. Genes regulated by REST/NRSF regulate multifaceted neuronal phenotypes, and their defects in the machinery cause neuropathies, disorders of neuron activity), autism and so on. In REST repressions, the N-terminal repressor domain recruits Sin3B via its paired amphipathic helix 1 (PAH1) domain, which plays an important role as a scaffold for histone deacetylase 1 and 2. This machinery has a critical role in maintaining neuronal robustness. In this study, in order to establish protein-protein interaction assays mimicking a binding surface between Sin3B and REST, we selected important amino acids from structural information of the PAH1/REST complex and then tried to reconstitute it using recombinant short peptides derived from PAH1/REST. Initially, we validated whether biotinylated REST interacts with glutathione S-transferase (GST)-tagged PAH1 and whether another PAH1 peptide (PAH1-FLAG) competitively binds with biotinylated REST using surface plasmon resonance (SPR). We observed a direct interaction and competitive binding of two PAH1 peptides. Secondly, in order to establish a high-throughput and high-dynamic-range assay, we utilized an easily performed novel time-resolved fluorescence energy transfer (TR-FRET) assay, and closely monitored this interaction. Finally, we succeeded in establishing a novel high-quality TR-FRET assay and a novel interaction assay based on SPR.


Assuntos
Transferência Ressonante de Energia de Fluorescência , Proteínas Repressoras/química , Ressonância de Plasmônio de Superfície , Humanos , Ligação Proteica , Proteínas Repressoras/metabolismo
4.
Mar Drugs ; 18(3)2020 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-32183121

RESUMO

Toxoplasma gondii is a major protozoan parasite and infects human and many other warm-blooded animals. The infection leads to Toxoplasmosis, a serious issue in AIDS patients, organ transplant recipients and pregnant women. Neospora caninum, another type of protozoa, is closely related to Toxoplasma gondii. Infections of the protozoa in animals also causes serious diseases such as Encephalomyelitis and Myositis-Polyradiculitis in dogs or abortion in cows. Both Toxoplasma gondii and Neospora caninum have similar nucleoside triphosphate hydrolases (NTPase), NcNTPase and TgNTPase-I in Neospora caninum and Toxoplasma gondii, respectively. These possibly play important roles in propagation and survival. Thus, we targeted the enzymes for drug discovery and tried to establish a novel high-standard assay by a combination of original biochemical enzyme assay and fluorescent assay to determine ADP content. We then validated whether or not it can be applied to high-throughput screening (HTS). Then, it fulfilled criterion to carry out HTS in both of the enzymes. In order to identify small molecules having inhibitory effects on the protozoan enzyme, we also performed HTS using two synthetic compound libraries and an extract library derived from marine bacteria and then, identified 19 compounds and 6 extracts. Nagasaki University collected many extracts from over 18,000 marine bacteria found in local Omura bay, and continues to compile an extensive collection of synthetic compounds from numerous drug libraries established by Japanese chemists.


Assuntos
Medições Luminescentes , Neospora/enzimologia , Nucleosídeo-Trifosfatase/análise , Toxoplasma/enzimologia , Animais , Humanos
5.
Mar Drugs ; 18(1)2020 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-31963531

RESUMO

Very recently, the immunotherapies against cancer, autoimmune diseases, and infection have been feasible and promising. Thus, we have examined the possibility whether or not human gamma delta T cells can be applied for the novel immunotherapies. We previously established the cells stably maintaining NFkB-driven human secreted embryonic alkaline phosphatase (SEAP) expression. The cells can be used to determine the transcription activity of NFkB with high-standard dynamic range and accuracy. Because IL-18 is a kind of cytokines that enhances cytotoxicity and activity of human gamma delta T cells through NFkB activation, we have focused on the activity and signaling of IL-18. In this study, we modified the previous reporter cell that can determine the transcription activity of NFkB to express two subunits consisted of human IL-18 receptor. The modified cells secreted SEAP in response to treatment with human recombinant IL-18 in a concentration-dependent manner. We also observed the concentration-dependently enhancement of NFkB activity in the cells treated with mouse recombinant IL-18 although the affinity was lower compared to human recombinant IL-18. We also previously established the cells stably expressing and secreting human recombinant IL-18 and then validated whether or not the conditioned medium from the cells activate NFkB transcription activity using this assay. Our university has kept collecting many extracts from over 18,000 marine bacteria in our local sea around Omura bay-fungi, plants for Chinese herbal medicine, and so on-and also have kept gathering synthetic compounds from many Japanese chemists as drug libraries. Finally, in order to identify drugs mimicking IL-18 biological activity or possessing inhibitory effects on IL-18-induced NFkB, we demonstrated drug screening using number of extracts derived from marine bacteria and synthetic compounds.


Assuntos
Interleucina-18/metabolismo , Transdução de Sinais/fisiologia , Organismos Aquáticos/metabolismo , Bactérias/metabolismo , Bioensaio/métodos , Avaliação Pré-Clínica de Medicamentos/métodos , Ensaios de Triagem em Larga Escala/métodos , Humanos , NF-kappa B/metabolismo
6.
J Pharmacol Sci ; 141(1): 56-63, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31611176

RESUMO

Concomitant heart failure is associated with poor clinical outcome in dialysis patients. The arteriovenous shunt, created as vascular access for hemodialysis, increases ventricular volume-overload, predisposing patients to developing cardiac dysfunction. The integral function of mitochondrial respiration is critically important for the heart to cope with hemodynamic overload. The involvement, however, of mitochondrial activity or reactive oxygen species (ROS) in the pathogenesis of ventricular-overload-induced heart failure has not been fully elucidated. We herein report that disorganization of mitochondrial respiration increases mitochondrial ROS production in the volume-overloaded heart, leading to ventricular dysfunction. We adopted the murine arteriovenous fistula (AVF) model, which replicates the cardinal features of volume-overload-induced ventricular dysfunction. Enzymatic assays of cardiac mitochondria revealed that the activities of citrate synthase and NADH-quinone reductase (complex Ⅰ) were preserved in the AVF heart. In contrast, the activity of NADH oxidase supercomplex was significantly compromised, resulting in elevated ROS production. Importantly, the antioxidant N-acetylcysteine prevented the development of ventricular dilatation and cardiac dysfunction, suggesting a pathogenic role for ROS in dialysis-related cardiomyopathy. A cardioprotective effect was also observed in metformin-treated mice, illuminating its potential use in the management of heart failure complicating diabetic patients on dialysis.


Assuntos
Acetilcisteína/uso terapêutico , Antioxidantes/uso terapêutico , Cardiomiopatias/tratamento farmacológico , Cardiomiopatias/etiologia , Mitocôndrias/metabolismo , Terapia de Alvo Molecular , Miócitos Cardíacos/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Acetilcisteína/farmacologia , Animais , Antioxidantes/farmacologia , Cardiomiopatias/metabolismo , Modelos Animais de Doenças , Insuficiência Cardíaca/etiologia , Insuficiência Cardíaca/prevenção & controle , Masculino , Camundongos Endogâmicos C57BL
7.
Int Heart J ; 60(4): 958-963, 2019 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-31308330

RESUMO

Myocardial infarction (MI) occurs when the heart muscle is severely damaged due to a decrease in blood flow from the coronary arteries. During recovery from an MI, cardiac fibroblasts become activated and produce extracellular matrices, contributing to the wound healing process in the damaged heart. Inappropriate activation of the fibroblasts leads to excessive fibrosis in the heart. However, the molecular pathways by which cardiac fibroblasts are activated have not yet been fully elucidated.Here we show that serum deprivation, which recapitulates the cellular microenvironment of the MI area, strikingly induces collagen production in C3H/10T1/2 cells. Based on transcriptomic and pharmacological studies, we found that cell cycle perturbation is directly linked to collagen production in fibroblasts. Importantly, collagen synthesis is increased independently of the transcriptional levels of type I collagen genes. These results reveal a novel mode of fibroblast activation in the ischemic area, which will allow us to gain insights into the molecular mechanisms underlying cardiac fibrosis and establish a basis for anti-fibrotic therapy.


Assuntos
Colágeno/biossíntese , Infarto do Miocárdio/metabolismo , Miócitos Cardíacos/metabolismo , Animais , Ciclo Celular , Células Cultivadas , Fibroblastos/metabolismo , Camundongos , Infarto do Miocárdio/patologia , Miócitos Cardíacos/patologia , Transdução de Sinais
8.
BMC Genomics ; 17(1): 899, 2016 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-27829362

RESUMO

BACKGROUND: Cancer microenvironment plays a vital role in cancer development and progression, and cancer-stromal interactions have been recognized as important targets for cancer therapy. However, identifying relevant and druggable cancer-stromal interactions is challenging due to the lack of quantitative methods to analyze whole cancer-stromal interactome. RESULTS: We present CASTIN (CAncer-STromal INteractome analysis), a novel framework for the evaluation of cancer-stromal interactome from RNA-Seq data using cancer xenograft models. For each ligand-receptor interaction which is derived from curated protein-protein interaction database, CASTIN summarizes gene expression profiles of cancer and stroma into three evaluation indices. These indices provide quantitative evaluation and comprehensive visualization of interactome, and thus enable to identify critical cancer-microenvironment interactions, which would be potential drug targets. We applied CASTIN to the dataset of pancreas ductal adenocarcinoma, and successfully characterized the individual cancer in terms of cancer-stromal relationships, and identified both well-known and less-characterized druggable interactions. CONCLUSIONS: CASTIN provides comprehensive view of cancer-stromal interactome and is useful to identify critical interactions which may serve as potential drug targets in cancer-microenvironment. CASTIN is available at: http://github.com/tmd-gpat/CASTIN .


Assuntos
Comunicação Celular , Neoplasias/etiologia , Neoplasias/metabolismo , Células Estromais/metabolismo , Microambiente Tumoral , Animais , Comunicação Celular/genética , Linhagem Celular Tumoral , Biologia Computacional , Modelos Animais de Doenças , Feminino , Perfilação da Expressão Gênica/métodos , Xenoenxertos , Humanos , Camundongos , Neoplasias/patologia , Mapeamento de Interação de Proteínas/métodos , Células Estromais/patologia , Transcriptoma , Microambiente Tumoral/genética , Fluxo de Trabalho
9.
Cancer Sci ; 107(10): 1527-1538, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27418196

RESUMO

YAP1, the main Hippo pathway effector, is a potent oncogene and is overexpressed in non-small-cell lung cancer (NSCLC); however, the YAP1 expression pattern in small-cell lung cancer (SCLC) has not yet been elucidated in detail. We report that the loss of YAP1 is a special feature of high-grade neuroendocrine lung tumors. A hierarchical cluster analysis of 15 high-grade neuroendocrine tumor cell lines containing 14 SCLC cell lines that depended on the genes of Hippo pathway molecules and neuroendocrine markers clearly classified these lines into two groups: the YAP1-negative and neuroendocrine marker-positive group (n = 11), and the YAP1-positive and neuroendocrine marker-negative group (n = 4). Among the 41 NSCLC cell lines examined, the loss of YAP1 was only observed in one cell line showing the strong expression of neuroendocrine markers. Immunostaining for YAP1, using the sections of 189 NSCLC, 41 SCLC, and 30 large cell neuroendocrine carcinoma (LCNEC) cases, revealed that the loss of YAP1 was common in SCLC (40/41, 98%) and LCNEC (18/30, 60%), but was rare in NSCLC (6/189, 3%). Among the SCLC and LCNEC cases tested, the loss of YAP1 correlated with the expression of neuroendocrine markers, and a survival analysis revealed that YAP1-negative cases were more chemosensitive than YAP1-positive cases. Chemosensitivity test for cisplatin using YAP1-positive/YAP1-negative SCLC cell lines also showed compatible results. YAP1-sh-mediated knockdown induced the neuroendocrine marker RAB3a, which suggested the possible involvement of YAP1 in the regulation of neuroendocrine differentiation. Thus, we showed that the loss of YAP1 has potential as a clinical marker for predicting neuroendocrine features and chemosensitivity.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/deficiência , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Tumores Neuroendócrinos/genética , Tumores Neuroendócrinos/patologia , Fosfoproteínas/deficiência , Animais , Antineoplásicos/farmacologia , Biomarcadores Tumorais , Linhagem Celular Tumoral , Cisplatino/farmacologia , Análise por Conglomerados , Modelos Animais de Doenças , Resistencia a Medicamentos Antineoplásicos/genética , Feminino , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Estudos de Associação Genética , Xenoenxertos , Humanos , Imuno-Histoquímica , Neoplasias Pulmonares/tratamento farmacológico , Masculino , Camundongos , Gradação de Tumores , Tumores Neuroendócrinos/tratamento farmacológico , Fatores de Transcrição , Transcriptoma , Proteínas de Sinalização YAP
10.
J Biol Chem ; 289(45): 30925-36, 2014 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-25124037

RESUMO

Antibody responses have been classified as being either T cell-dependent or T cell-independent (TI). TI antibody responses are further classified as being either type 1 (TI-1) or type 2 (TI-2), depending on their requirement for B cell-mediated antigen receptor signaling. Although the mechanistic basis of antibody responses has been studied extensively, it remains unclear whether different antibody responses share similarities in their transcriptional regulation. Here, we show that mice deficient in IκB-ζ, specifically in their B cells, have impaired TI-1 antibody responses but normal T cell-dependent and TI-2 antibody responses. The absence of IκB-ζ in B cells also impaired proliferation triggered by Toll-like receptor (TLR) activation, plasma cell differentiation, and class switch recombination (CSR). Mechanistically, IκB-ζ-deficient B cells could not induce TLR-mediated induction of activation-induced cytidine deaminase (AID), a class-switch DNA recombinase. Retroviral transduction of AID in IκB-ζ-deficient B cells restored CSR activity. Furthermore, acetylation of histone H3 in the vicinity of the transcription start site of the gene that encodes AID was reduced in IκB-ζ-deficient B cells relative to IκB-ζ-expressing B cells. These results indicate that IκB-ζ regulates TLR-mediated CSR by inducing AID. Moreover, IκB-ζ defines differences in the transcriptional regulation of different antibody responses.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Linfócitos B/metabolismo , Regulação da Expressão Gênica , Proteínas Nucleares/metabolismo , Linfócitos T/imunologia , Receptores Toll-Like/metabolismo , Alelos , Animais , Formação de Anticorpos/imunologia , Antígenos CD40/metabolismo , Diferenciação Celular , Linhagem Celular , Proliferação de Células , Citidina Desaminase/metabolismo , Histonas/química , Switching de Imunoglobulina , Lipopolissacarídeos/química , Camundongos , Receptores de Antígenos de Linfócitos B/metabolismo , Recombinases/metabolismo , Recombinação Genética , Transdução de Sinais , Baço/citologia , Receptores Toll-Like/imunologia
11.
Genome Res ; 22(2): 208-19, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22156295

RESUMO

Whole-exome sequencing (Exome-seq) has been successfully applied in several recent studies. We here sequenced the exomes of 15 pancreatic tumor cell lines and their matched normal samples. We captured 162,073 exons of 16,954 genes and sequenced the targeted regions to a mean coverage of 56-fold. This study identified a total of 1517 somatic mutations and validated 934 mutations by transcriptome sequencing. We detected recurrent mutations in 56 genes. Among them, 41 have not been described. The mutation rates varied widely among cell lines. The diversity of the mutation rates was significantly correlated with the distinct MLH1 copy-number status. Exome-seq revealed intensive genomic instability in a cell line with MLH1 homozygous deletion, indicated by a dramatically elevated rate of somatic substitutions, small insertions/deletions (indels), as well as indels in microsatellites. Notably, we found that MLH1 expression was decreased by nearly half in cell lines with an allelic loss of MLH1. While these cell lines were negative in conventional microsatellite instability assay, they showed a 10.5-fold increase in the rate of somatic indels, e.g., truncating indels in TP53 and TGFBR2, indicating MLH1 haploinsufficiency in the correction of DNA indel errors. We further analyzed the exomes of 15 renal cell carcinomas and confirmed MLH1 haploinsufficiency. We observed a much higher rate of indel mutations in the affected cases and identified recurrent truncating indels in several cancer genes such as VHL, PBRM1, and JARID1C. Together, our data suggest that MLH1 hemizygous deletion, through increasing the rate of indel mutations, could drive the development and progression of sporadic cancers.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Exoma , Instabilidade Genômica , Haploinsuficiência , Proteínas Nucleares/genética , Neoplasias Pancreáticas/genética , Alelos , Linhagem Celular Tumoral , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Perda de Heterozigosidade , Proteína 1 Homóloga a MutL , Mutação , Taxa de Mutação , Reprodutibilidade dos Testes
12.
J Biol Chem ; 288(52): 36948-56, 2013 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-24214985

RESUMO

Post-translational histone methylation is a dynamic and reversible process that is involved in the spatio-temporal regulation of gene transcription and contributes to various cellular phenotypes. Methylation of histone H3 at lysine 9 (H3K9), which is generally a transcriptional repression mark, is demethylated by H3K9-specific demethylases, leading to transcriptional activation. However, how multiple demethylases with the same substrate specificity differ in their chromatin targeting mechanisms has not been well understood. Unlike other H3K9-specific demethylases, it has been reported that JMJD1A likely forms a homodimer, but a detailed mode of dimerization and the possible link between structure and enzymatic activity have remained unresolved. Here, we report the structure-function relationship of JMJD1A in detail. First, JMJD1A forms a homodimer through its catalytic domains, bringing the two active sites close together. Second, increasing the concentration of JMJD1A facilitates efficient production of unmethylated product from dimethyl-H3K9 and decreases the release of the monomethylated intermediate. Finally, substituting one of the two active sites with an inactive mutant results in a significant reduction of the demethylation rate without changing the affinity to the intermediate. Given this evidence, we propose a substrate channeling model for the efficient conversion of dimethylated H3K9 into the unmethylated state. Our study provides valuable information that will help in understanding the redundancy of H3K9-specific demethylases and the complementary activity of their unique structures and enzymatic properties for appropriate control of chromatin modification patterns.


Assuntos
Histonas/metabolismo , Histona Desmetilases com o Domínio Jumonji/metabolismo , Modelos Biológicos , Multimerização Proteica/fisiologia , Domínio Catalítico , Linhagem Celular , Histonas/genética , Humanos , Histona Desmetilases com o Domínio Jumonji/genética , Metilação , Mutação , Relação Estrutura-Atividade
13.
Biochim Biophys Acta Mol Basis Dis ; 1870(6): 167249, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38768929

RESUMO

RET fusion is an oncogenic driver in 1-2 % of patients with non-small cell lung cancer (NSCLC). Although RET-positive tumors have been treated with multikinase inhibitors such as vandetanib or RET-selective inhibitors, ultimately resistance to them develops. Here we established vandetanib resistance (VR) clones from LC-2/ad cells harboring CCDC6-RET fusion and explored the molecular mechanism of the resistance. Each VR clone had a distinct phenotype, implying they had acquired resistance via different mechanisms. Consistently, whole exome-seq and RNA-seq revealed that the VR clones had unique mutational signatures and expression profiles, and shared only a few common remarkable events. AXL and IGF-1R were activated as bypass pathway in different VR clones, and sensitive to a combination of RET and AXL inhibitors or IGF-1R inhibitors, respectively. SMARCA4 loss was also found in a particular VR clone and 55 % of post-TKI lung tumor tissues, being correlated with higher sensitivity to SMARCA4/SMARCA2 dual inhibition and shorter PFS after subsequent treatments. Finally, we detected an increased number of damaged mitochondria in one VR clone, which conferred sensitivity to mitochondrial electron transfer chain inhibitors. Increased mitochondria were also observed in post-TKI biopsy specimens in 13/20 cases of NSCLC, suggesting a potential strategy targeting mitochondria to treat resistant tumors. Our data propose new promising therapeutic options to combat resistance to RET inhibitors in NSCLC.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Resistencia a Medicamentos Antineoplásicos , Neoplasias Pulmonares , Mitocôndrias , Piperidinas , Inibidores de Proteínas Quinases , Proteínas Proto-Oncogênicas c-ret , Humanos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Proteínas Proto-Oncogênicas c-ret/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-ret/genética , Proteínas Proto-Oncogênicas c-ret/metabolismo , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/genética , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Mitocôndrias/metabolismo , Mitocôndrias/efeitos dos fármacos , Piperidinas/farmacologia , Piperidinas/uso terapêutico , Inibidores de Proteínas Quinases/uso terapêutico , Inibidores de Proteínas Quinases/farmacologia , Linhagem Celular Tumoral , Quinazolinas/farmacologia , Quinazolinas/uso terapêutico , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Fatores de Transcrição/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos , Proteínas de Fusão Oncogênica/genética , Proteínas de Fusão Oncogênica/metabolismo , Proteínas de Fusão Oncogênica/antagonistas & inibidores , DNA Helicases/genética , DNA Helicases/metabolismo , DNA Helicases/antagonistas & inibidores , Proteínas do Citoesqueleto
14.
Cell Mol Gastroenterol Hepatol ; 17(5): 745-767, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38309455

RESUMO

BACKGROUND & AIMS: Colorectal cancer (CRC) is the third most common cancer in the world. Gut microbiota has recently been implicated in the development of CRC. Actinomyces odontolyticus is one of the most abundant bacteria in the gut of patients with very early stages of CRC. A odontolyticus is an anaerobic bacterium existing principally in the oral cavity, similar to Fusobacterium nucleatum, which is known as a colon carcinogenic bacterium. Here we newly determined the biological functions of A odontolyticus on colonic oncogenesis. METHODS: We examined the induction of intracellular signaling by A odontolyticus in human colonic epithelial cells (CECs). DNA damage levels in CECs were confirmed using the human induced pluripotent stem cell-derived gut organoid model and mouse colon tissues in vivo. RESULTS: A odontolyticus secretes membrane vesicles (MVs), which induce nuclear factor kappa B signaling and also produce excessive reactive oxygen species (ROS) in colon epithelial cells. We found that A odontolyticus secretes lipoteichoic acid-rich MVs, promoting inflammatory signaling via TLR2. Simultaneously, those MVs are internalized into the colon epithelial cells, co-localize with the mitochondria, and cause mitochondrial dysfunction, resulting in excessive ROS production and DNA damage. Induction of excessive DNA damage in colonic cells by A odontolyticus-derived MVs was confirmed in the gut organoid model and also in mouse colon tissues. CONCLUSIONS: A odontolyticus secretes MVs, which cause chronic inflammation and ROS production in colonic epithelial cells, leading to the initiation of CRC.


Assuntos
Colo , Células-Tronco Pluripotentes Induzidas , Camundongos , Animais , Humanos , Colo/microbiologia , Espécies Reativas de Oxigênio , Composição de Bases , Filogenia , RNA Ribossômico 16S , Análise de Sequência de DNA , Células Epiteliais , Bactérias/genética
15.
Nat Metab ; 6(6): 1108-1127, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38822028

RESUMO

Oxygen is critical for all metazoan organisms on the earth and impacts various biological processes in physiological and pathological conditions. While oxygen-sensing systems inducing acute hypoxic responses, including the hypoxia-inducible factor pathway, have been identified, those operating in prolonged hypoxia remain to be elucidated. Here we show that pyridoxine 5'-phosphate oxidase (PNPO), which catalyses bioactivation of vitamin B6, serves as an oxygen sensor and regulates lysosomal activity in macrophages. Decreased PNPO activity under prolonged hypoxia reduced an active form of vitamin B6, pyridoxal 5'-phosphate (PLP), and inhibited lysosomal acidification, which in macrophages led to iron dysregulation, TET2 protein loss and delayed resolution of the inflammatory response. Among PLP-dependent metabolism, supersulfide synthesis was suppressed in prolonged hypoxia, resulting in the lysosomal inhibition and consequent proinflammatory phenotypes of macrophages. The PNPO-PLP axis creates a distinct layer of oxygen sensing that gradually shuts down PLP-dependent metabolism in response to prolonged oxygen deprivation.


Assuntos
Lisossomos , Macrófagos , Fosfato de Piridoxal , Lisossomos/metabolismo , Macrófagos/metabolismo , Animais , Camundongos , Fosfato de Piridoxal/metabolismo , Hipóxia/metabolismo , Hipóxia Celular , Vitamina B 6/metabolismo , Oxigênio/metabolismo , Inflamação/metabolismo
16.
Carcinogenesis ; 34(10): 2380-8, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23698634

RESUMO

Alterations in genes coding for histone modifiers are found in human cancers, suggesting that histone modification is involved in malignant features of neoplastic cells. This study showed that a histone demethylase KDM4C is significant for colonosphere formation by mediating the cross talk between oncogenic pathways through a feed-forward mechanism. The expression of KDM4C gene was increased in spheres from colorectal cancer (CRC) cells and the knockdown (KD) of KDM4C eliminated colonosphere formation. We found that the KD of ß-catenin, an important oncogenic factor in CRC, resulted in not only decreased sphere formation but also impaired upregulation of KDM4C gene in spheres. ß-Catenin bound to the KDM4C promoter, suggesting that KDM4C is involved in the sphere-forming ability downstream of ß-catenin in CRC cells. Microarray analysis identified the JAG1 gene that codes for a notch ligand Jagged1 responsible for sphere formation as a target of KDM4C. KDM4C KD decreased the expression of JAG1 gene, and the downregulation of JAG1 gene recapitulated the impaired colonosphere formation. JAG1 is also a target of ß-catenin, and chromatin immunoprecipitation analysis showed the binding of ß-catenin and KDM4C onto the JAG1 promoter during colonosphere formation. Importantly, KDM4C KD ruined the recruitment of ß-catenin onto the JAG1 promoter independently of the H3-K9 methylation status and blunted JAG1 expression during sphere formation. These data indicate that KDM4C maintains the sphere-forming capacity in CRCs by mediating the ß-catenin-dependent transcription of JAG1 in a feed-forward manner.


Assuntos
Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Histona Desmetilases com o Domínio Jumonji/genética , Receptores Notch/metabolismo , Transdução de Sinais , Proteínas Wnt/metabolismo , Animais , Proteínas de Ligação ao Cálcio/genética , Proteínas de Ligação ao Cálcio/metabolismo , Linhagem Celular Tumoral , Neoplasias Colorretais/patologia , Regulação Neoplásica da Expressão Gênica , Xenoenxertos , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/genética , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Proteína Jagged-1 , Histona Desmetilases com o Domínio Jumonji/metabolismo , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Camundongos , Modelos Biológicos , Regiões Promotoras Genéticas , Ligação Proteica , Proteínas Serrate-Jagged , Esferoides Celulares , Carga Tumoral/genética , Células Tumorais Cultivadas , beta Catenina/genética , beta Catenina/metabolismo
17.
Hum Mol Genet ; 20(14): 2710-21, 2011 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-21505077

RESUMO

Epigenetic regulation is essential in determining cellular phenotypes during differentiation. Although tissue-specific DNA methylation has been studied, the significance of methylation variance for tissue phenotypes remains unresolved, especially for CpG-poor promoters. Here, we comprehensively studied methylation levels of 27 578 CpG sites among 21 human normal tissues from 12 anatomically different regions using an epigenotyping beadarray system. Remarkable changes in tissue-specific DNA methylation were observed within CpG-poor promoters but not CpG-rich promoters. Of note, tissue-specific hypomethylation is accompanied by an increase in gene expression, which gives rise to specialized cellular functions. The hypomethylated regions were significantly enriched with recognition motifs for transcription factors that regulate cell-type-specific differentiation. To investigate the dynamics of hypomethylation events, we analyzed methylation levels of the entire APOA1 gene locus during in vitro differentiation of embryonic stem cells toward the hepatic lineage. A decrease in methylation was observed after day 13, coinciding with alpha-fetoprotein detection, in the vicinity of its transcription start sites (TSSs), and extends up to ∼200 bp region encompassing the TSS at day 21, equivalent to the hepatoblastic stage. This decrease is even more pronounced in the adult liver, where the entire APOA1 gene locus is hypomethylated. Furthermore, when we compared the methylation status of induced pluripotent stem (iPS) cells with their parental cell, IMR-90, we found that fibroblast-specific hypomethylation is restored to a fully methylated state in iPS cells after reprogramming. These results illuminate tissue-specific methylation dynamics in CpG-poor promoters and provide more comprehensive views on spatiotemporal gene regulation in terminal differentiation.


Assuntos
Diferenciação Celular/fisiologia , Ilhas de CpG/fisiologia , Metilação de DNA/fisiologia , Regiões Promotoras Genéticas/fisiologia , Adulto , Células-Tronco Embrionárias/citologia , Células-Tronco Embrionárias/metabolismo , Feminino , Estudo de Associação Genômica Ampla , Humanos , Masculino , Especificidade de Órgãos/fisiologia
18.
Nat Commun ; 14(1): 8031, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-38052804

RESUMO

Cancer cells inevitably interact with neighboring host tissue-resident cells during the process of metastatic colonization, establishing a metastatic niche to fuel their survival, growth, and invasion. However, the underlying mechanisms in the metastatic niche are yet to be fully elucidated owing to the lack of methodologies for comprehensively studying the mechanisms of cell-cell interactions in the niche. Here, we improve a split green fluorescent protein (GFP)-based genetically encoded system to develop secretory glycosylphosphatidylinositol-anchored reconstitution-activated proteins to highlight intercellular connections (sGRAPHIC) for efficient fluorescent labeling of tissue-resident cells that neighbor on and putatively interact with cancer cells in deep tissues. The sGRAPHIC system enables the isolation of metastatic niche-associated tissue-resident cells for their characterization using a single-cell RNA sequencing platform. We use this sGRAPHIC-leveraged transcriptomic platform to uncover gene expression patterns in metastatic niche-associated hepatocytes in a murine model of liver metastasis. Among the marker genes of metastatic niche-associated hepatocytes, we identify Lgals3, encoding galectin-3, as a potential pro-metastatic factor that accelerates metastatic growth and invasion.


Assuntos
Neoplasias Hepáticas , Humanos , Camundongos , Animais , Neoplasias Hepáticas/metabolismo , Hepatócitos/metabolismo , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Matriz Extracelular/metabolismo , Comunicação Celular
19.
J Vis Exp ; (185)2022 07 22.
Artigo em Inglês | MEDLINE | ID: mdl-35938815

RESUMO

Protozoan parasites infect humans and many warm-blooded animals. Toxoplasma gondii, a major protozoan parasite, is commonly found in HIV-positive patients, organ transplant recipients and pregnant women, resulting in the severe health condition, Toxoplasmosis. Another major protozoan, Neospora caninum, which bears many similarities to Toxoplasma gondii, causes serious diseases in animals, as does Encephalomyelitis and Myositis-Polyradiculitis in dogs and cows, resulting in stillborn calves. All these exhibited similar nucleoside triphosphate hydrolases (NTPase). Neospora caninum has a NcNTPase, while Toxoplasma gondii has a TgNTPase-I. The enzymes are thought to play crucial roles in propagation and survival. In order to establish compounds and/or extracts preventing protozoan infection, we targeted these enzymes for drug discovery. The next step was to establish a novel, highly sensitive, and highly accurate assay by combining a conventional biochemical enzyme assay with a fluorescent assay to determine ADP content. We also validated that the novel assay fulfills the criteria to carry out high-throughput screening (HTS) in the two protozoan enzymes. We performed HTS, identified 19 compounds and six extracts from two synthetic compound libraries and an extract library derived from marine bacteria, respectively. In this study, a detailed explanation has been introduced on how to carry out HTS, including information about the preparation of reagents, devices, robot arm, etc.


Assuntos
Coccidiose , Neospora , Robótica , Toxoplasma , Animais , Anticorpos Antiprotozoários , Bovinos , Coccidiose/parasitologia , Coccidiose/veterinária , Cães , Feminino , Ensaios de Triagem em Larga Escala , Humanos , Hidrolases , N-Glicosil Hidrolases , Nucleosídeos , Polifosfatos , Gravidez
20.
Cell Stem Cell ; 29(10): 1459-1474.e9, 2022 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-36113462

RESUMO

Fibrosis is the final path of nearly every form of chronic disease, regardless of the pathogenesis. Upon chronic injury, activated, fibrogenic fibroblasts deposit excess extracellular matrix, and severe tissue fibrosis can occur in virtually any organ. However, antifibrotic therapies that target fibrogenic cells, while sparing homeostatic fibroblasts in healthy tissues, are limited. We tested whether specific immunization against endogenous proteins, strongly expressed in fibrogenic cells but highly restricted in quiescent fibroblasts, can elicit an antigen-specific cytotoxic T cell response to ameliorate organ fibrosis. In silico epitope prediction revealed that activation of the genes Adam12 and Gli1 in profibrotic cells and the resulting "self-peptides" can be exploited for T cell vaccines to ablate fibrogenic cells. We demonstrate the efficacy of a vaccination approach to mount CD8+ T cell responses that reduce fibroblasts and fibrosis in the liver and lungs in mice. These results provide proof of principle for vaccination-based immunotherapies to treat fibrosis.


Assuntos
Fibroblastos , Pulmão , Animais , Epitopos/metabolismo , Fibroblastos/metabolismo , Fibrose , Imunoterapia , Fígado/patologia , Pulmão/metabolismo , Camundongos , Vacinação , Proteína GLI1 em Dedos de Zinco/metabolismo
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