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1.
Nucleic Acids Res ; 52(D1): D1265-D1275, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-37953279

RESUMO

First released in 2006, DrugBank (https://go.drugbank.com) has grown to become the 'gold standard' knowledge resource for drug, drug-target and related pharmaceutical information. DrugBank is widely used across many diverse biomedical research and clinical applications, and averages more than 30 million views/year. Since its last update in 2018, we have been actively enhancing the quantity and quality of the drug data in this knowledgebase. In this latest release (DrugBank 6.0), the number of FDA approved drugs has grown from 2646 to 4563 (a 72% increase), the number of investigational drugs has grown from 3394 to 6231 (a 38% increase), the number of drug-drug interactions increased from 365 984 to 1 413 413 (a 300% increase), and the number of drug-food interactions expanded from 1195 to 2475 (a 200% increase). In addition to this notable expansion in database size, we have added thousands of new, colorful, richly annotated pathways depicting drug mechanisms and drug metabolism. Likewise, existing datasets have been significantly improved and expanded, by adding more information on drug indications, drug-drug interactions, drug-food interactions and many other relevant data types for 11 891 drugs. We have also added experimental and predicted MS/MS spectra, 1D/2D-NMR spectra, CCS (collision cross section), RT (retention time) and RI (retention index) data for 9464 of DrugBank's 11 710 small molecule drugs. These and other improvements should make DrugBank 6.0 even more useful to a much wider research audience ranging from medicinal chemists to metabolomics specialists to pharmacologists.


Assuntos
Bases de Conhecimento , Metabolômica , Espectrometria de Massas em Tandem , Bases de Dados Factuais , Interações Alimento-Droga
2.
Reprod Biol Endocrinol ; 21(1): 43, 2023 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-37170094

RESUMO

Endometrial epithelia are known to harbor cancer driver mutations in the absence of any pathologies, including mutations in PIK3CA. Insulin plays an important role in regulating uterine metabolism during pregnancy, and hyperinsulinemia is associated with conditions impacting fertility. Hyperinsulinemia also promotes cancer, but the direct action of insulin on mutated endometrial epithelial cells is unknown. Here, we treated 12Z endometriotic epithelial cells carrying the PIK3CAH1047R oncogene with insulin and examined transcriptomes by RNA-seq. While cells naively responded to insulin, the magnitude of differential gene expression (DGE) was nine times greater in PIK3CAH1047R cells, representing a synergistic effect between insulin signaling and PIK3CAH1047R expression. Interferon signaling and the unfolded protein response (UPR) were enriched pathways among affected genes. Insulin treatment in wild-type cells activated normal endoplasmic reticulum stress (ERS) response programs, while PIK3CAH1047R cells activated programs necessary to avoid ERS-induced apoptosis. PIK3CAH1047R expression alone resulted in overexpression (OE) of Viperin (RSAD2), which is involved in viral response and upregulated in the endometrium during early pregnancy. The transcriptional changes induced by insulin in PIK3CAH1047R cells were rescued by knockdown of Viperin, while Viperin OE alone was insufficient to induce a DGE response to insulin, suggesting that Viperin is necessary but not sufficient for the synergistic effect of PIK3CAH1047R and insulin treatment. We identified interferon signaling, viral response, and protein targeting pathways that are induced by insulin but dependent on Viperin in PIK3CAH1047R mutant cells. These results suggest that response to insulin signaling is altered in mutated endometriotic epithelial cells.


Assuntos
Hiperinsulinismo , Neoplasias , Feminino , Humanos , Classe I de Fosfatidilinositol 3-Quinases/genética , Classe I de Fosfatidilinositol 3-Quinases/metabolismo , Células Epiteliais/metabolismo , Insulina/farmacologia , Insulina/genética , Interferons/genética , Mutação , Endométrio/metabolismo
3.
Reprod Biol Endocrinol ; 20(1): 163, 2022 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-36424602

RESUMO

Obesity impacts fertility and is positively correlated with endometrial hyperplasia and endometrial cancer occurrence. Endometrial epithelia often harbor disease driver-mutations, while endometrial stroma are highly regulative of neighboring epithelia. Here, we sought to determine distinct transcriptome changes occurring in individual cell types in the obese mouse uterus. Outbred CD-1 mice were fed high-fat or control diets for 18 weeks, estrous cycle staged, and endometrial epithelia, macrophages, and stroma isolated for transcriptomic analysis. High-fat diet mice displayed increased body mass and developed glucose intolerance, hyperinsulinemia, and fatty liver. Obese mouse epithelia displayed differential gene expression for genes related to innate immunity and leukocyte chemotaxis. The obese mouse stroma differentially expressed factors related to circadian rhythm, and expression of these genes correlated with glucose tolerance or body mass. We observed correlations between F4/80 + macrophage numbers, Cleaved Caspase 3 (CC3) apoptosis marker staining and glucose intolerance among obese mice, including a subgroup of obese mice with high CC3 + luminal epithelia. This subgroup displayed differential gene expression among all cell types, with pathways related to immune escape in epithelia and macrophages, while the stroma dysregulated pathways related to regulation of epithelia. These results suggest an important role for differential response of both the epithelia and stroma in their response to obesity, while macrophages are dysregulated in the context of apoptotic epithelia. The obesity-related gene expression programs in cells within the uterine microenvironment may influence the ability of the endometrium to function during pregnancy and influence disease pathogenesis.


Assuntos
Intolerância à Glucose , Transcriptoma , Gravidez , Feminino , Camundongos , Animais , Camundongos Obesos , Obesidade/genética , Obesidade/metabolismo , Dieta Hiperlipídica/efeitos adversos
4.
BMC Biol ; 20(1): 209, 2022 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-36153585

RESUMO

BACKGROUND: SWI/SNF (BAF) chromatin remodeling complexes regulate lineage-specific enhancer activity by promoting accessibility for diverse DNA-binding factors and chromatin regulators. Additionally, they are known to modulate the function of the epigenome through regulation of histone post-translational modifications and nucleosome composition, although the way SWI/SNF complexes govern the epigenome remains poorly understood. Here, we investigate the function of ARID1A, a subunit of certain mammalian SWI/SNF chromatin remodeling complexes associated with malignancies and benign diseases originating from the uterine endometrium. RESULTS: Through genome-wide analysis of human endometriotic epithelial cells, we show that more than half of ARID1A binding sites are marked by the variant histone H3.3, including active regulatory elements such as super-enhancers. ARID1A knockdown leads to H3.3 depletion and gain of canonical H3.1/3.2 at ARID1A-bound active regulatory elements, and a concomitant redistribution of H3.3 toward genic elements. ARID1A interactions with the repressive chromatin remodeler CHD4 (NuRD) are associated with H3.3, and ARID1A is required for CHD4 recruitment to H3.3. ZMYND8 interacts with CHD4 to suppress a subset of ARID1A, CHD4, and ZMYND8 co-bound, H3.3+ H4K16ac+ super-enhancers near genes governing extracellular matrix, motility, adhesion, and epithelial-to-mesenchymal transition. Moreover, these gene expression alterations are observed in human endometriomas. CONCLUSIONS: These studies demonstrate that ARID1A-containing BAF complexes are required for maintenance of the histone variant H3.3 at active regulatory elements, such as super-enhancers, and this function is required for the physiologically relevant activities of alternative chromatin remodelers.


Assuntos
Cromatina , Proteínas de Ligação a DNA , Histonas , Fatores de Transcrição , Cromatina/genética , Montagem e Desmontagem da Cromatina , DNA , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Feminino , Histonas/genética , Humanos , Complexo Mi-2 de Remodelação de Nucleossomo e Desacetilase/genética , Complexo Mi-2 de Remodelação de Nucleossomo e Desacetilase/metabolismo , Nucleossomos , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
5.
J Neurosci Methods ; 378: 109643, 2022 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-35691412

RESUMO

BACKGROUND: Limitations have previously existed for the use of brain infusion catheters with extended delivery port designs to achieve larger distribution volumes using convection-enhanced delivery (CED), due to poor transmittance of materials and uncontrolled backflow. The goal of this study was to evaluate a novel brain catheter that has been designed to allow for extended delivery and larger distribution volumes with limited backflow of fluid. It was characterized using a broad range of therapeutic pore sizes both for transmittance across the membranes to address possible occlusion and for distribution in short term infusion studies, both in-vitro in gels and in-vivo in canines. METHODS: Brain catheters with pore sizes of 10, 12, 15, 20 and 30 µm were evaluated using three infusates prepared in 0.9% sterile saline with diameters approximating 2, 5, and 30 nm, respectively. Magnevist™ was chosen as the small molecule infusate to mimic low-molecular weight therapeutics. Galbumin™ served as a surrogate for an assortment of proteins used for brain cancer and Parkinson's disease. Gadoluminate™ was used to assess the distribution of large therapeutics, such as adeno-associated viral particles and synthetic nanoparticles. The transmittance of the medium and large tracer particles through catheters of different pore size (15, 20 and 30 µm) was measured by MRI and compared with the measured concentration of the control. Infusions into 0.2% agarose gels were performed in order to evaluate differences in transmittance and distribution of the small, medium, and large tracer particles through catheters with different pore sizes (10, 12, 15, 20 and 30 µm). In-vivo infusions were performed in the canine in order to evaluate the ability of the catheter to infuse the small, medium, and large tracer particles into brain parenchyma at high flow rates through catheters with different pore sizes (10, 15, and 20 µm). Two catheters were stereotactically inserted into the brain for infusion, one per hemisphere, in each animal (N = 6). RESULTS: The transmittance of Galbumin and Gadoluminate across the catheter membrane surface was 100% to within the accuracy of the measurements. There was no evidence of any blockage or retardation of any of the infusates. Catheter pore size did not appear to significantly affect transmittance or distribution in gels of any of the molecule sizes in the range of catheter pore sizes tested. There were differences in the distributions between the different tracer molecules: Magnevist produced relatively large distributions, followed by Gadoluminate and Galbumin. We observed no instances of uncontrolled backflow in a total of 12 in-vivo infusions. In addition, several of the infusions resulted in substantial amounts remaining in tissue. We expect the in-tissue distributions to be substantially improved in the larger human brain. COMPARISON WITH EXISTING METHODS: The new porous brain catheter performed well in terms of both backflow and intraparenchymal infusion of molecules of varying size in the canine brain under CED flow conditions. CONCLUSIONS: Overall, the data presented in this report support that the novel porous brain catheter can deliver therapeutics of varying sizes at high infusion rates in the brain parenchyma, and resist backflow that can compromise the efficacy of CED therapy. Additional work is needed to further characterize the brain catheter, including animal toxicity studies of chronically implanted brain catheters to lay the foundation for its use in the clinic.


Assuntos
Catéteres , Sistemas de Liberação de Medicamentos , Animais , Encéfalo/diagnóstico por imagem , Convecção , Cães , Sistemas de Liberação de Medicamentos/métodos , Géis , Humanos , Imageamento por Ressonância Magnética , Porosidade
6.
Reprod Sci ; 29(11): 3266-3277, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35616875

RESUMO

Endometriosis is a disease defined by the presence of abnormal endometrium at ectopic sites, causing pain and infertility in 10% of women. Mutations in the chromatin remodeling protein ARID1A (AT-rich interactive domain-containing protein 1A) have been identified in endometriosis, particularly in the more severe deep infiltrating endometriosis and ovarian endometrioma subtypes. ARID1A has been shown to regulate chromatin at binding sites of the Activator Protein 1 (AP-1) transcription factor, and AP-1 expression has been shown in multiple endometriosis models. Here, we describe a role for AP-1 subunit JUNB in promoting invasive phenotypes in endometriosis. Through a series of knockdown experiments in the 12Z endometriosis cell line, we show that JUNB expression in endometriosis promotes the expression of epithelial-to-mesenchymal transition genes co-regulated by ARID1A including transcription factors SNAI1 and SNAI2, cell adhesion molecules ICAM1 and VCAM1, and extracellular matrix remodelers LOX and LOXL2. In highly invasive ARID1A-deficient endometriotic cells, co-knockdown of JUNB is sufficient to suppress invasion. These results suggest that AP-1 plays an important role in the progression of invasive endometriosis, and that therapeutic inhibition of AP-1 could prevent the occurrence of deep infiltrating endometriosis.


Assuntos
Endometriose , Humanos , Feminino , Endometriose/genética , Endometriose/metabolismo , Fator de Transcrição AP-1/metabolismo , Endométrio/metabolismo , Transição Epitelial-Mesenquimal , Fenótipo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
7.
Cells ; 11(6)2022 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-35326450

RESUMO

Endometrial cancer (EC) is characterized by high estrogen levels unopposed by progesterone. Treatment with progestins is standard for early EC, but the response to progestins is dependent on progesterone receptor (PGR) expression. Here, we show that the expression of PGR in endometrial epithelial cells is dependent on ARID1A, a DNA-binding subunit of the SWI/SNF chromatin-remodeling complex that is commonly mutated in EC. In endometrial epithelial cells with estrogen receptor overexpression, we find that ARID1A promotes estrogen signaling and regulates common gene expression programs. Normally, endometrial epithelial cells expressing estrogen receptors respond to estrogen by upregulating the PGR. However, when ARID1A expression is lost, upregulation of PGR expression is significantly reduced. This phenomenon can also occur following the loss of the SWI/SNF subunit BRG1, suggesting a role for ARID1A- and BRG1-containing complexes in PGR regulation. We find that PGR is regulated by a bivalent promoter, which harbors both H3K4me3 and H3K27me3 histone tail modifications. H3K27me3 is deposited by EZH2, and inhibition of EZH2 in the context of ARID1A loss results in restoration of estrogen-induced PGR expression. Our results suggest a role for ARID1A deficiency in the loss of PGR in late-stage EC and a therapeutic utility for EZH2 inhibitors in this disease.


Assuntos
Histonas , Proteínas Nucleares , Estrogênios/farmacologia , Feminino , Humanos , Proteínas Nucleares/metabolismo , Progestinas/farmacologia , Receptores de Progesterona/metabolismo
8.
PLoS Genet ; 17(12): e1009986, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34941867

RESUMO

TP53 and ARID1A are frequently mutated across cancer but rarely in the same primary tumor. Endometrial cancer has the highest TP53-ARID1A mutual exclusivity rate. However, the functional relationship between TP53 and ARID1A mutations in the endometrium has not been elucidated. We used genetically engineered mice and in vivo genomic approaches to discern both unique and overlapping roles of TP53 and ARID1A in the endometrium. TP53 loss with oncogenic PIK3CAH1047R in the endometrial epithelium results in features of endometrial hyperplasia, adenocarcinoma, and intraepithelial carcinoma. Mutant endometrial epithelial cells were transcriptome profiled and compared to control cells and ARID1A/PIK3CA mutant endometrium. In the context of either TP53 or ARID1A loss, PIK3CA mutant endometrium exhibited inflammatory pathway activation, but other gene expression programs differed based on TP53 or ARID1A status, such as epithelial-to-mesenchymal transition. Gene expression patterns observed in the genetic mouse models are reflective of human tumors with each respective genetic alteration. Consistent with TP53-ARID1A mutual exclusivity, the p53 pathway is activated following ARID1A loss in the endometrial epithelium, where ARID1A normally directly represses p53 pathway genes in vivo, including the stress-inducible transcription factor, ATF3. However, co-existing TP53-ARID1A mutations led to invasive adenocarcinoma associated with mutant ARID1A-driven ATF3 induction, reduced apoptosis, TP63+ squamous differentiation and invasion. These data suggest TP53 and ARID1A mutations drive shared and distinct tumorigenic programs in the endometrium and promote invasive endometrial cancer when existing simultaneously. Hence, TP53 and ARID1A mutations may co-occur in a subset of aggressive or metastatic endometrial cancers, with ARID1A loss promoting squamous differentiation and the acquisition of invasive properties.


Assuntos
Proteínas de Ligação a DNA/genética , Neoplasias do Endométrio/genética , Fatores de Transcrição/genética , Proteína Supressora de Tumor p53/genética , Proteínas Supressoras de Tumor/genética , Adenocarcinoma/genética , Adenocarcinoma/patologia , Animais , Carcinogênese/genética , Carcinoma in Situ/genética , Carcinoma in Situ/patologia , Classe I de Fosfatidilinositol 3-Quinases/genética , Hiperplasia Endometrial/genética , Hiperplasia Endometrial/patologia , Neoplasias do Endométrio/patologia , Endométrio/patologia , Transição Epitelial-Mesenquimal/genética , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Camundongos , Mutação/genética
9.
PLoS One ; 16(7): e0253872, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34197511

RESUMO

Technologies and practices that reduce the environmental impacts of US agriculture are well documented. Less is known about how best to encourage their adoption. We report on the results of a large randomized controlled trial conducted with nearly 10,000 agricultural producers in the United States. The experiment was embedded in US Department of Agriculture outreach efforts to improve soil conservation practices. USDA varied the content of mailings to test two sets of competing theories about outreach to agricultural producers. Contrary to conventional wisdom, we find no evidence that acknowledging the link between climate change and agricultural production discourages conservation action. Furthermore, we find that producers who were invited to a webinar were less likely to take any action to learn more about conservation practices than producers who were not told about the webinar, a result that runs counter to the popular wisdom that offering more options leads to more action.


Assuntos
Mudança Climática , Conservação dos Recursos Naturais/métodos , Produção Agrícola/métodos , Fazendeiros/estatística & dados numéricos , Solo , Conservação dos Recursos Naturais/estatística & dados numéricos , Conservação dos Recursos Naturais/tendências , Produção Agrícola/estatística & dados numéricos , Produção Agrícola/tendências , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Inquéritos e Questionários/estatística & dados numéricos , Estados Unidos , United States Department of Agriculture/estatística & dados numéricos
10.
Nucleic Acids Res ; 49(W1): W597-W602, 2021 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-34019658

RESUMO

Comprehensive, predictive computational models have significant potential for science, bioengineering, and medicine. One promising way to achieve more predictive models is to combine submodels of multiple subsystems. To capture the multiple scales of biology, these submodels will likely require multiple modeling frameworks and simulation algorithms. Several community resources are already available for working with many of these frameworks and algorithms. However, the variety and sheer number of these resources make it challenging to find and use appropriate tools for each model, especially for novice modelers and experimentalists. To make these resources easier to use, we developed RunBioSimulations (https://run.biosimulations.org), a single web application for executing a broad range of models. RunBioSimulations leverages community resources, including BioSimulators, a new open registry of simulation tools. These resources currently enable RunBioSimulations to execute nine frameworks and 44 algorithms, and they make RunBioSimulations extensible to additional frameworks and algorithms. RunBioSimulations also provides features for sharing simulations and interactively visualizing their results. We anticipate that RunBioSimulations will foster reproducibility, stimulate collaboration, and ultimately facilitate the creation of more predictive models.


Assuntos
Simulação por Computador , Modelos Biológicos , Software , Algoritmos , Biologia Computacional , Internet
12.
Cell Rep ; 33(6): 108366, 2020 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-33176148

RESUMO

Endometriosis affects 1 in 10 women and is characterized by the presence of abnormal endometrium at ectopic sites. ARID1A mutations are observed in deeply invasive forms of the disease, often correlating with malignancy. To identify epigenetic dependencies driving invasion, we use an unbiased approach to map chromatin state transitions accompanying ARID1A loss in the endometrium. We show that super-enhancers marked by high H3K27 acetylation are strongly associated with ARID1A binding. ARID1A loss leads to H3K27 hyperacetylation and increased chromatin accessibility and enhancer RNA transcription at super-enhancers, but not typical enhancers, indicating that ARID1A normally prevents super-enhancer hyperactivation. ARID1A co-localizes with P300 at super-enhancers, and genetic or pharmacological inhibition of P300 in ARID1A mutant endometrial epithelia suppresses invasion and induces anoikis through the rescue of super-enhancer hyperacetylation. Among hyperactivated super-enhancers, SERPINE1 (PAI-1) is identified as an essential target gene driving ARID1A mutant endometrial invasion. Broadly, our findings provide rationale for therapeutic strategies targeting super-enhancers in ARID1A mutant endometrium.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Endometriose/metabolismo , Endométrio/metabolismo , Fatores de Transcrição/metabolismo , Acetilação , Animais , Endometriose/patologia , Endométrio/patologia , Feminino , Humanos , Camundongos , Mutação , Coelhos , Ratos
13.
Hum Mol Genet ; 29(20): 3412-3430, 2020 12 18.
Artigo em Inglês | MEDLINE | ID: mdl-33075803

RESUMO

Although ARID1A mutations are a hallmark feature, mutations in other SWI/SNF (SWItch/Sucrose Non-Fermentable) chromatin remodeling subunits are also observed in endometrial neoplasms. Here, we interrogated the roles of Brahma/SWI2-related gene 1 (BRG1, SMARCA4), the SWI/SNF catalytic subunit, in the endometrial epithelium. BRG1 loss affects more than one-third of all active genes and highly overlaps with the ARID1A gene regulatory network. Chromatin immunoprecipitation studies revealed widespread subunit-specific differences in transcriptional regulation, as BRG1 promoter interactions are associated with gene activation, while ARID1A binding is associated with gene repression. However, we identified a physiologically relevant subset of BRG1 and ARID1A co-regulated epithelial identity genes. Mice were genetically engineered to inactivate BRG1 specifically in the endometrial epithelium. Endometrial glands were observed embedded in uterine myometrium, indicating adenomyosis-like phenotypes. Molecular similarities were observed between BRG1 and ARID1A mutant endometrial cells in vivo, including loss of epithelial cell adhesion and junction genes. Collectively, these studies illustrate overlapping contributions of multiple SWI/SNF subunit mutations in the translocation of endometrium to distal sites, with loss of cell integrity being a common feature in SWI/SNF mutant endometrial epithelia.


Assuntos
Montagem e Desmontagem da Cromatina , DNA Helicases/fisiologia , Proteínas de Ligação a DNA/fisiologia , Endométrio/patologia , Epitélio/patologia , Regulação da Expressão Gênica , Mutação , Proteínas Nucleares/fisiologia , Fatores de Transcrição/fisiologia , Animais , Endométrio/metabolismo , Epitélio/metabolismo , Feminino , Camundongos , Camundongos Knockout
14.
Stem Cell Res ; 46: 101849, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32464345

RESUMO

The Wnt pathway co-receptor, Leucine Rich Repeat Containing G Protein-Coupled Receptor 5 (LGR5), labels tumor-prone stem cell populations in certain types of tissue. In this study, we show that ARID1A and PIK3CA mutations in LGR5+ cells result in renal angiosarcomas in adult mice. The tumors originate in the renal medulla. We further show that LGR5 labels SOX17+/CD31+/CD34+/CD133+/AQP1+/CD146+ endothelial progenitor cells within the descending vasa recta or straight arterioles of the kidney, which are specialized capillaries that maintain medullary osmotic gradients necessary for water reabsorption and the production of concentrated urine. LGR5+ endothelial progenitor cells are tightly associated with contractile pericytes within the descending vasa recta. Long-term in vivo lineage tracing revealed that LGR5+ cells give rise to renal medullary vasculature. We further show that LGR5+ cells are activated in response to ischemic kidney injury. Our findings uncover a physiologically relevant endothelial progenitor cell population within the kidney vasa recta.


Assuntos
Células Progenitoras Endoteliais , Neoplasias , Animais , Capilares , Rim , Medula Renal , Camundongos , Receptores Acoplados a Proteínas G/genética
15.
Epigenetics Chromatin ; 13(1): 22, 2020 04 22.
Artigo em Inglês | MEDLINE | ID: mdl-32321567

RESUMO

BACKGROUND: Chromatin dysregulation is associated with developmental disorders and cancer. Numerous methods for measuring genome-wide chromatin accessibility have been developed in the genomic era to interrogate the function of chromatin regulators. A recent technique which has gained widespread use due to speed and low input requirements with native chromatin is the Assay for Transposase-Accessible Chromatin, or ATAC-seq. Biologists have since used this method to compare chromatin accessibility between two cellular conditions. However, approaches for calculating differential accessibility can yield conflicting results, and little emphasis is placed on choice of normalization method during differential ATAC-seq analysis, especially when global chromatin alterations might be expected. RESULTS: Using an in vivo ATAC-seq data set generated in our recent report, we observed differences in chromatin accessibility patterns depending on the data normalization method used to calculate differential accessibility. This observation was further verified on published ATAC-seq data from yeast. We propose a generalized workflow for differential accessibility analysis using ATAC-seq data. We further show this workflow identifies sites of differential chromatin accessibility that correlate with gene expression and is sensitive to differential analysis using negative controls. CONCLUSIONS: We argue that researchers should systematically compare multiple normalization methods before continuing with differential accessibility analysis. ATAC-seq users should be aware of the interpretations of potential bias within experimental data and the assumptions of the normalization method implemented.


Assuntos
Sequenciamento de Cromatina por Imunoprecipitação/métodos , Cromatina/química , Algoritmos , Cromatina/genética , Sequenciamento de Cromatina por Imunoprecipitação/normas , Interpretação Estatística de Dados , Genoma Fúngico , Saccharomyces cerevisiae
16.
J Extracell Vesicles ; 9(1): 1706708, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32002170

RESUMO

Microvesicles (MVs), a plasma membrane-derived subclass of extracellular vesicles, are produced and released into the circulation during systemic inflammation, yet little is known of cell/tissue-specific uptake of MVs under these conditions. We hypothesized that monocytes contribute to uptake of circulating MVs and that their increased margination to the pulmonary circulation and functional priming during systemic inflammation produces substantive changes to the systemic MV homing profile. Cellular uptake of i.v.-injected, fluorescently labelled MVs (J774.1 macrophage-derived) in vivo was quantified by flow cytometry in vascular cell populations of the lungs, liver and spleen of C57BL6 mice. Under normal conditions, both Ly6Chigh and Ly6Clow monocytes contributed to MV uptake but liver Kupffer cells were the dominant target cell population. Following induction of sub-clinical endotoxemia with low-dose i.v. LPS, MV uptake by lung-marginated Ly6Chigh monocytes increased markedly, both at the individual cell level (~2.5-fold) and through substantive expansion of their numbers (~8-fold), whereas uptake by splenic macrophages was unchanged and uptake by Kupffer cells actually decreased (~50%). Further analysis of MV uptake within the pulmonary vasculature using a combined model approach of in vivo macrophage depletion, ex vivo isolated perfused lungs and in vitro lung perfusate cell-based assays, indicated that Ly6Chigh monocytes possess a high MV uptake capacity (equivalent to Kupffer cells), that is enhanced directly by endotoxemia and ablated in the presence of phosphatidylserine (PS)-enriched liposomes and ß3 integrin receptor blocking peptide. Accordingly, i.v.-injected PS-enriched liposomes underwent a redistribution of cellular uptake during endotoxemia similar to MVs, with enhanced uptake by Ly6Chigh monocytes and reduced uptake by Kupffer cells. These findings indicate that monocytes, particularly lung-marginated Ly6Chigh subset monocytes, become a dominant target cell population for MVs during systemic inflammation, with significant implications for the function and targeting of endogenous and therapeutically administered MVs, lending novel insights into the pathophysiology of pulmonary vascular inflammation.

17.
Hum Reprod ; 35(1): 58-69, 2020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31886851

RESUMO

STUDY QUESTION: Is it possible to establish a genetically engineered mouse model (GEMM) of endometriosis that mimics the natural spread of invasive endometrium? SUMMARY ANSWER: Endometriosis occurs in an ARID1A (AT-rich interactive domain-containing protein 1A) and PIK3CA (phosphatidylinositol-4,5-bisphosphate 3-kinase, catalytic subunit alpha) mutant GEMM of endometrial dysfunction following salpingectomy. WHAT IS KNOWN ALREADY: Although mouse models of endometriosis have long been established, most models rely on intraperitoneal injection of uterine fragments, steroid hormone treatments or the use of immune-compromised mice. STUDY DESIGN, SIZE, DURATION: Mice harboring the lactotransferrin-Cre (LtfCre0/+), Arid1afl, (Gt)R26Pik3ca*H1047R and (Gt)R26mTmG alleles were subject to unilateral salpingectomies at 6 weeks of age. Control (n = 9), LtfCre0/+; (Gt)R26Pik3ca*H1047R; Arid1afl/+ (n = 8) and LtfCre0/+; (Gt)R26Pik3ca*H1047R; Arid1afl/fl (n = 9) were used for the study. The (Gt)R26mTmG allele was used for the purpose of fluorescent lineage tracing of endometrial epithelium. LtfCre0/+; (Gt)R26mTmG (n = 3) and LtfCre0/+; (Gt)R26Pik3ca*H1047R/mTmG; Arid1afl/fl (n = 4) were used for this purpose. Mice were followed until the endpoint of vaginal bleeding at an average time of 17 weeks of age. PARTICIPANTS/MATERIALS, SETTING, METHODS: At 6 weeks of age, mice were subjected to salpingectomy surgery. Mice were followed until the time point of vaginal bleeding (average 17 weeks), or aged for 1 year in the case of control mice. At time of sacrifice, endometriotic lesions, ovaries and uterus were collected for the purpose of histochemical and immunohistochemical analyses. Samples were analyzed for markers of the endometriotic tissue and other relevant biomarkers. MAIN RESULTS AND THE ROLE OF CHANCE: Following salpingectomy, LtfCre0/+; (Gt)R26Pik3ca*H1047R/mTmG; Arid1afl/fl mice developed endometriotic lesions, including lesions on the ovary, omentum and abdominal wall. Epithelial glands within lesions were negative for ARID1A and positive for phospho-S6 staining, indicating ARID1A-PIK3CA co-mutation status, and expressed EGFP (enhanced green fluorescent protein), indicating endometrial origins. LARGE-SCALE DATA: N/A. LIMITATIONS, REASONS FOR CAUTION: LtfCre0/+; (Gt)R26Pik3ca*H1047R; Arid1afl/fl mice develop vaginal bleeding as a result of endometrial dysfunction at an average age of 17 weeks and must be sacrificed. Furthermore, while this model mimics the natural spread of endometriotic tissue directly from the uterus to the peritoneum, the data presented do not reject current hypotheses on endometriosis pathogenesis. WIDER IMPLICATIONS OF THE FINDINGS: The idea that endometriosis is the result of abnormal endometrial tissue colonizing the peritoneum via retrograde menstruation has gained widespread support over the past century. However, most models of endometriosis take for granted this possibility, relying on the surgical removal of bulk uterine tissue and subsequent transplantation into the peritoneum. Growing evidence suggests that somatic mutations in ARID1A and PIK3CA are present in the endometrial epithelium. The establishment of a GEMM which mimics the natural spread of endometrium and subsequent lesion formation supports the hypothesis that endometriosis is derived from mutant endometrial epithelium with invasive properties. STUDY FUNDING/COMPETING INTEREST(S): This research was supported by the American Cancer Society PF-17-163-02-DDC (M.R.W.), the Mary Kay Foundation 026-16 (R.L.C.) and the Ovarian Cancer Research Fund Alliance 457446 (R.L.C.). The authors declare no competing interests.


Assuntos
Endometriose , Idoso , Animais , Modelos Animais de Doenças , Endométrio , Feminino , Humanos , Distúrbios Menstruais , Camundongos , Peritônio
18.
Ecol Evol ; 9(22): 12858-12868, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31788220

RESUMO

Quantitative models play an increasing role in exploring the impact of global change on biodiversity. To win credibility and trust, they need validating. We show how expert knowledge can be used to assess a large number of empirical species niche models constructed for the British vascular plant and bryophyte flora. Key outcomes were (a) scored assessments of each modeled species and niche axis combination, (b) guidance on models needing further development, (c) exploration of the trade-off between presenting more complex model summaries, which could lead to more thorough validation, versus the longer time these take to evaluate, (d) quantification of the internal consistency of expert opinion based on comparison of assessment scores made on a random subset of models evaluated by both experts. Overall, the experts assessed 39% of species and niche axis combinations to be "poor" and 61% to show a degree of reliability split between "moderate" (30%), "good" (25%), and "excellent" (6%). The two experts agreed in only 43% of cases, reaching greater consensus about poorer models and disagreeing most about models rated as better by either expert. This low agreement rate suggests that a greater number of experts is required to produce reliable assessments and to more fully understand the reasons underlying lack of consensus. While area under curve (AUC) statistics showed generally very good ability of the models to predict random hold-out samples of the data, there was no correspondence between these and the scores given by the experts and no apparent correlation between AUC and species prevalence. Crowd-sourcing further assessments by allowing web-based access to model fits is an obvious next step. To this end, we developed an online application for inspecting and evaluating the fit of each niche surface to its training data.

19.
Nat Commun ; 10(1): 3554, 2019 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-31391455

RESUMO

ARID1A and PI3-Kinase (PI3K) pathway alterations are common in neoplasms originating from the uterine endometrium. Here we show that monoallelic loss of ARID1A in the mouse endometrial epithelium is sufficient for vaginal bleeding when combined with PI3K activation. Sorted mutant epithelial cells display gene expression and promoter chromatin signatures associated with epithelial-to-mesenchymal transition (EMT). We further show that ARID1A is bound to promoters with open chromatin, but ARID1A loss leads to increased promoter chromatin accessibility and the expression of EMT genes. PI3K activation partially rescues the mesenchymal phenotypes driven by ARID1A loss through antagonism of ARID1A target gene expression, resulting in partial EMT and invasion. We propose that ARID1A normally maintains endometrial epithelial cell identity by repressing mesenchymal cell fates, and that coexistent ARID1A and PI3K mutations promote epithelial transdifferentiation and collective invasion. Broadly, our findings support a role for collective epithelial invasion in the spread of abnormal endometrial tissue.


Assuntos
Transformação Celular Neoplásica/genética , Classe I de Fosfatidilinositol 3-Quinases/genética , Proteínas de Ligação a DNA/genética , Neoplasias do Endométrio/genética , Transição Epitelial-Mesenquimal/genética , Proteínas Nucleares/genética , Fosfatidilinositol 3-Quinases/genética , Fatores de Transcrição/genética , Animais , Linhagem Celular , Movimento Celular/genética , Cromatina/metabolismo , Classe I de Fosfatidilinositol 3-Quinases/metabolismo , Proteínas de Ligação a DNA/metabolismo , Modelos Animais de Doenças , Neoplasias do Endométrio/patologia , Endométrio/patologia , Feminino , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Haploinsuficiência , Humanos , Mutação com Perda de Função , Camundongos , Camundongos Transgênicos , Miométrio/patologia , Invasividade Neoplásica/genética , Proteínas Nucleares/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Transdução de Sinais/genética , Fatores de Transcrição/metabolismo
20.
Sci Rep ; 8(1): 16006, 2018 10 30.
Artigo em Inglês | MEDLINE | ID: mdl-30375484

RESUMO

Dexamethasone (Dex), co-administered to lung adenocarcinoma patients with pemetrexed chemotherapy, protects against pemetrexed cytotoxicity by inducing reversible G1 arrest, reflected by the effect of Dex on FLT-PET images of patient tumors. However, perioperative Dex treatment increases survival but the mechanism is unknown. In cells with glucocorticoid receptor-α (GR) expression corresponding to higher clinical tumor levels, Dex-induced growth arrest was followed by marked cell expansion, beta-galactosidase expression and Ki67 negativity, despite variable p53 and K-RAS status. Dex induced a transient early surge in p21Cip1. However, a progressive, irreversible loss of clonogenic growth, whose time of onset was dependent on GR level and Dex dose, was independent of p21Cip1and caused by gradual accumulation of p27Kip1 due to transcriptional activation of p27Kip1 by Dex. This effect was independent of canonical pathways of senescence or p27Kip1 regulation. The in vitro observations were reflected by growth suppression and P27Kip1 induction in GR-overexpressing tumor xenografts compared with isogenic low-GR tumors. Extended Dex treatment induces irreversible cell cycle blockade and a senescence phenotype through chronic activation of the p27Kip1 gene in GR overexpressing lung tumor cell populations and hence could improve outcome of surgery/pemetrexed chemotherapy and sensitize tumors to immunotherapy.


Assuntos
Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Inibidor de Quinase Dependente de Ciclina p27/genética , Dexametasona/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Receptores de Glucocorticoides/genética , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Senescência Celular/efeitos dos fármacos , Senescência Celular/genética , Inibidor de Quinase Dependente de Ciclina p27/metabolismo , Relação Dose-Resposta a Droga , Humanos , Imuno-Histoquímica , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Fenótipo , Estabilidade de RNA , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores de Glucocorticoides/metabolismo
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