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1.
J Clin Invest ; 133(6)2023 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-36919699

RESUMO

High mobility group A1 (HMGA1) chromatin regulators are upregulated in diverse tumors where they portend adverse outcomes, although how they function in cancer remains unclear. Pancreatic ductal adenocarcinomas (PDACs) are highly lethal tumors characterized by dense desmoplastic stroma composed predominantly of cancer-associated fibroblasts and fibrotic tissue. Here, we uncover an epigenetic program whereby HMGA1 upregulates FGF19 during tumor progression and stroma formation. HMGA1 deficiency disrupts oncogenic properties in vitro while impairing tumor inception and progression in KPC mice and subcutaneous or orthotopic models of PDAC. RNA sequencing revealed HMGA1 transcriptional networks governing proliferation and tumor-stroma interactions, including the FGF19 gene. HMGA1 directly induces FGF19 expression and increases its protein secretion by recruiting active histone marks (H3K4me3, H3K27Ac). Surprisingly, disrupting FGF19 via gene silencing or the FGFR4 inhibitor BLU9931 recapitulates most phenotypes observed with HMGA1 deficiency, decreasing tumor growth and formation of a desmoplastic stroma in mouse models of PDAC. In human PDAC, overexpression of HMGA1 and FGF19 defines a subset of tumors with extremely poor outcomes. Our results reveal what we believe is a new paradigm whereby HMGA1 and FGF19 drive tumor progression and stroma formation, thus illuminating FGF19 as a rational therapeutic target for a molecularly defined PDAC subtype.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Animais , Humanos , Camundongos , Carcinogênese/genética , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/patologia , Linhagem Celular Tumoral , Proliferação de Células , Fatores de Crescimento de Fibroblastos/genética , Fatores de Crescimento de Fibroblastos/metabolismo , Inativação Gênica , Proteína HMGA1a/genética , Proteína HMGA1a/metabolismo , Neoplasias Pancreáticas/patologia
2.
PLoS One ; 17(3): e0266343, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35358279

RESUMO

BACKGROUND: The "Coronavirus Disease 2019" (COVID-19) pandemic has become a major challenge for all healthcare systems worldwide, and besides generating a high toll of deaths, it has caused economic losses. Hospitals have played a key role in providing services to patients and the volume of hospital activities has been refocused on COVID-19 patients. Other activities have been limited/repurposed or even suspended and hospitals have been operating with reduced capacity. With the decrease in non-COVID-19 activities, their financial system and sustainability have been threatened, with hospitals facing shortage of financial resources. The aim of this study was to investigate the effects of COVID-19 on the revenues of public hospitals in Lorestan province in western Iran, as a case study. METHOD: In this quasi-experimental study, we conducted the interrupted time series analysis to evaluate COVID-19 induced changes in monthly revenues of 18 public hospitals, from April 2018 to August 2021, in Lorestan, Iran. In doing so, public hospitals report their earnings to the University of Medical Sciences monthly; then, we collected this data through the finance office. RESULTS: Due to COVID-19, the revenues of public hospitals experienced an average monthly decrease of $172,636 thousand (P-value = 0.01232). For about 13 months, the trend of declining hospital revenues continued. However, after February 2021, a relatively stable increase could be observed, with patient admission and elective surgeries restrictions being lifted. The average monthly income of hospitals increased by $83,574 thousand. CONCLUSION: COVID-19 has reduced the revenues of public hospitals, which have faced many problems due to the high costs they have incurred. During the crisis, lack of adequate fundings can damage healthcare service delivery, and policymakers should allocate resources to prevent potential shocks.


Assuntos
COVID-19 , COVID-19/epidemiologia , Hospitais Públicos , Humanos , Análise de Séries Temporais Interrompida , Irã (Geográfico)/epidemiologia , Admissão do Paciente
3.
Mol Biol Rep ; 49(1): 605-615, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34657251

RESUMO

OBJECTIVE: Severe acute respiratory syndrome coronavirus 2 (SARS-COV2) was first detected in Wuhan, China in December, 2019. The emerging virus causes a respiratory illness, that can trigger a cytokine storm in the body. METHOD: Cytokine storm in patient's body is associated with severe forms of disease. It is one of the main complications of coronavirus disease-2019 (COVID-19), in which immune cells play a major role. Studies have shown immune cells in the tumor environment can be effective to induce resistance to chemotherapy in cancer patients. RESULT: Therefore, considering the role of immune cells to induce cytokine storm in COVID-19 patients, and their role to cause resistance to chemotherapy, they are effective on disease progression and creation of severe form of disease. CONCLUSION: By examining the signaling pathways and inducing resistance to chemotherapy in tumor cells and the cells affect them, it is possible to prevent the occurrence of severe forms of the disease in cancer patients with COVID-19; it is applicable using target therapy and other subsequent treatment strategies.


Assuntos
COVID-19 , Síndrome da Liberação de Citocina , Neoplasias/tratamento farmacológico , Antineoplásicos/uso terapêutico , COVID-19/complicações , COVID-19/imunologia , Resistência a Medicamentos , Humanos , SARS-CoV-2/imunologia
4.
Ethiop J Health Sci ; 31(6): 1109-1114, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35392347

RESUMO

Background: In February 2020, the Ministry of Health and Medical Education in Iran announced the first case of COVID-19. The aim of this study was to investigate the impact of COVID-19 on the number of CT-Scans and MRI services in public hospitals in western Iran. Methods: We collected CT-scans and MRI services data from 18 public hospitals via Vice-Chancellor Office, Lorestan University of Medical Sciences from January 2017 to February 2021. Interrupted time series analysis (ITSA) was conducted to assess the impact of COVID-19 on CT-Scans and MRI services. More specifically, ITSA was conducted using ordinary least squares regression with the number of CT-Scans and MRI services per 1,000 registered persons per month as dependent variable. Results: At the beginning of the observation period, the monthly rate of CT-Scans was constant (p for trend = 0.267) at 291.9 (from 95%CI 240.5 to 343.4) per 1,000 registered patients. The first case of COVID-19 coincided with an abrupt increase by 211.8 (from 95%CI 102.9 to 320.7) per 1,000 patients. Thereafter, the trend of CT-Scans did not change (p=0.576) compared to the pre-pandemic period. The rate of MRI services was 363.5 per 1,000 per registered patients per month (P = <0.0001) with a slightly decreasing trend (coefficient=-5; 95%CI, -6.9 to -3.1). Conclusion: The findings of this study showed that crises such as COVID-19 can affect the service delivery process. Health policymakers and decision makers should work to prevent potential reductions in health care during events such as COVID-19.


Assuntos
COVID-19 , COVID-19/diagnóstico por imagem , COVID-19/epidemiologia , Hospitais Públicos , Humanos , Análise de Séries Temporais Interrompida , Irã (Geográfico)/epidemiologia , Imageamento por Ressonância Magnética , Tomografia Computadorizada por Raios X
5.
Gigascience ; 9(10)2020 10 20.
Artigo em Inglês | MEDLINE | ID: mdl-33079170

RESUMO

BACKGROUND: The vast ecosystem of single-cell RNA-sequencing tools has until recently been plagued by an excess of diverging analysis strategies, inconsistent file formats, and compatibility issues between different software suites. The uptake of 10x Genomics datasets has begun to calm this diversity, and the bioinformatics community leans once more towards the large computing requirements and the statistically driven methods needed to process and understand these ever-growing datasets. RESULTS: Here we outline several Galaxy workflows and learning resources for single-cell RNA-sequencing, with the aim of providing a comprehensive analysis environment paired with a thorough user learning experience that bridges the knowledge gap between the computational methods and the underlying cell biology. The Galaxy reproducible bioinformatics framework provides tools, workflows, and trainings that not only enable users to perform 1-click 10x preprocessing but also empower them to demultiplex raw sequencing from custom tagged and full-length sequencing protocols. The downstream analysis supports a range of high-quality interoperable suites separated into common stages of analysis: inspection, filtering, normalization, confounder removal, and clustering. The teaching resources cover concepts from computer science to cell biology. Access to all resources is provided at the singlecell.usegalaxy.eu portal. CONCLUSIONS: The reproducible and training-oriented Galaxy framework provides a sustainable high-performance computing environment for users to run flexible analyses on both 10x and alternative platforms. The tutorials from the Galaxy Training Network along with the frequent training workshops hosted by the Galaxy community provide a means for users to learn, publish, and teach single-cell RNA-sequencing analysis.


Assuntos
Ecossistema , Software , Biologia Computacional , RNA , Análise de Sequência de RNA
6.
J Proteome Res ; 18(2): 782-790, 2019 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-30582332

RESUMO

Next-generation sequencing technologies, coupled to advances in mass-spectrometry-based proteomics, have facilitated system-wide quantitative profiling of expressed mRNA transcripts and proteins. Proteo-transcriptomic analysis compares the relative abundance levels of transcripts and their corresponding proteins, illuminating discordant gene product responses to perturbations. These results reveal potential post-transcriptional regulation, providing researchers with important new insights into underlying biological and pathological disease mechanisms. To carry out proteo-transcriptomic analysis, researchers require software that statistically determines transcript-protein abundance correlation levels and provides results visualization and interpretation functionality, ideally within a flexible, user-friendly platform. As a solution, we have developed the QuanTP software within the Galaxy platform. The software offers a suite of tools and functionalities critical for proteo-transcriptomics, including statistical algorithms for assessing the correlation between single transcript-protein pairs as well as across two cohorts, outlier identification and clustering, along with a diverse set of results visualizations. It is compatible with analyses of results from single experiment data or from a two-cohort comparison of aggregated replicate experiments. The tool is available in the Galaxy Tool Shed through a cloud-based instance and a Docker container. In all, QuanTP provides an accessible and effective software resource, which should enable new multiomic discoveries from quantitative proteo-transcriptomic data sets.


Assuntos
Biologia Computacional/métodos , Análise de Dados , Perfilação da Expressão Gênica/métodos , Proteômica/métodos , Software , Animais , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Espectrometria de Massas
7.
Cancer Res ; 77(21): e43-e46, 2017 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-29092937

RESUMO

Proteogenomics has emerged as a valuable approach in cancer research, which integrates genomic and transcriptomic data with mass spectrometry-based proteomics data to directly identify expressed, variant protein sequences that may have functional roles in cancer. This approach is computationally intensive, requiring integration of disparate software tools into sophisticated workflows, challenging its adoption by nonexpert, bench scientists. To address this need, we have developed an extensible, Galaxy-based resource aimed at providing more researchers access to, and training in, proteogenomic informatics. Our resource brings together software from several leading research groups to address two foundational aspects of proteogenomics: (i) generation of customized, annotated protein sequence databases from RNA-Seq data; and (ii) accurate matching of tandem mass spectrometry data to putative variants, followed by filtering to confirm their novelty. Directions for accessing software tools and workflows, along with instructional documentation, can be found at z.umn.edu/canresgithub. Cancer Res; 77(21); e43-46. ©2017 AACR.


Assuntos
Biologia Computacional/métodos , Genômica/métodos , Neoplasias/genética , Software , Genoma Humano , Humanos , Proteômica/métodos , Espectrometria de Massas em Tandem , Transcriptoma/genética
8.
Gynecol Oncol ; 141(3): 580-587, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27001612

RESUMO

OBJECTIVES: Although uterine cancer is the fourth most common cause for cancer death in women worldwide, the molecular underpinnings of tumor progression remain poorly understood. The High Mobility Group A1 (HMGA1) gene is overexpressed in aggressive cancers and high levels portend adverse outcomes in diverse tumors. We previously reported that Hmga1a transgenic mice develop uterine tumors with complete penetrance. Because HMGA1 drives tumor progression by inducing MatrixMetalloproteinase (MMP) and other genes involved in invasion, we explored the HMGA1-MMP-2 pathway in uterine cancer. METHODS: To investigate MMP-2 in uterine tumors driven by HMGA1, we used a genetic approach with mouse models. Next, we assessed HMGA1 and MMP-2 expression in primary human uterine tumors, including low-grade carcinomas (endometrial endometrioid) and more aggressive tumors (endometrial serous carcinomas, uterine carcinosarcomas/malignant mesodermal mixed tumors). RESULTS: Here, we report for the first time that uterine tumor growth is impaired in Hmga1a transgenic mice crossed on to an Mmp-2 deficient background. In human tumors, we discovered that HMGA1 is highest in aggressive carcinosarcomas and serous carcinomas, with lower levels in the more indolent endometrioid carcinomas. Moreover, HMGA1 and MMP-2 were positively correlated, but only in a subset of carcinosarcomas. HMGA1 also occupies the MMP-2 promoter in human carcinosarcoma cells. CONCLUSIONS: Together, our studies define a novel HMGA1-MMP-2 pathway involved in a subset of human carcinosarcomas and tumor progression in murine models. Our work also suggests that targeting HMGA1 could be effective adjuvant therapy for more aggressive uterine cancers and provides compelling data for further preclinical studies.


Assuntos
Carcinossarcoma/genética , Cistadenocarcinoma Seroso/genética , Proteína HMGA1a/genética , Metaloproteinase 2 da Matriz/genética , Neoplasias Uterinas/genética , Animais , Carcinossarcoma/metabolismo , Imunoprecipitação da Cromatina , Cistadenocarcinoma Seroso/metabolismo , Feminino , Inativação Gênica , Proteína HMGA1a/biossíntese , Humanos , Masculino , Metaloproteinase 2 da Matriz/biossíntese , Camundongos Transgênicos , Regiões Promotoras Genéticas , Regulação para Cima , Neoplasias Uterinas/metabolismo
9.
J Proteomics Bioinform ; 72014 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-25544807

RESUMO

An increasingly common method for predicting gene activity is genome-wide chromatin immuno-precipitation of 'active' chromatin modifications followed by massively parallel sequencing (ChIP-seq). In order to understand better the relationship between developmentally regulated chromatin landscapes and regulation of early B cell development, we determined how differentially active promoter regions were able to predict relative RNA and protein levels at the pre-pro-B and pro-B stages. Herein, we describe a novel ChIP-seq quantification method (cRPKM) to identify active promoters and a multi-omics approach that compares promoter chromatin status with ongoing active transcription (GRO-seq), steady state mRNA (RNA-seq), inferred mRNA stability, and relative proteome abundance measurements (iTRAQ). We demonstrate that active chromatin modifications at promoters are good indicators of transcription and steady state mRNA levels. Moreover, we found that promoters with active chromatin modifications exclusively in one of these cell states frequently predicted the differential abundance of proteins. However, we found that many genes whose promoters have non-differential but active chromatin modifications also displayed changes in abundance of their cognate proteins. As expected, this large class of developmentally and differentially regulated proteins that was uncoupled from chromatin status used mostly post-transcriptional mechanisms. Strikingly, the most differentially abundant protein in our B-cell development system, 2410004B18Rik, was regulated by a post-transcriptional mechanism, which further analyses indicated was mediated by a micro-RNA. These data highlight how this integrated multi-omics data set can be a useful resource in uncovering regulatory mechanisms. This data can be accessed at: https://usegalaxy.org/u/thereddylab/p/prediction-of-gene-activity-based-on-an-integrative-multi-omics-analysis.

10.
Mol Genet Genomics ; 287(11-12): 867-79, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23052832

RESUMO

The HuR protein regulates the expression of thousands of cellular transcripts by modulating mRNA splicing, trafficking, translation, and stability. Although it serves as a model of RNA-protein interactions, many features of HuR's interactions with RNAs remain unknown. In this report, we deployed the cryogenic RNA immunoprecipitation technique to analyze HuR-interacting RNAs with the Affymetrix all-exon microarray platform. We revealed several thousand novel HuR-interacting RNAs, including hundreds of non-coding RNAs such as natural antisense transcripts from stress responsive loci. To gain insight into the mechanisms of specificity and sensitivity of HuR's interaction with its target RNAs, we searched HuR-interacting RNAs for composite patterns of primary sequence and secondary structure. We provide evidence that secondary structures of 66-75 nucleotides enhance HuR's recognition of its specific RNA targets composed of short primary sequence patterns. We validated thousands of these RNAs by analysis of overlap with recently published findings, including HuR's interaction with RNAs in the pathways of RNA splicing and stability. Finally, we observed a striking enrichment for members of ubiquitin ligase pathways among the HuR-interacting mRNAs, suggesting a new role for HuR in the regulation of protein degradation to mirror its known function in protein translation.


Assuntos
Proteínas ELAV/metabolismo , RNA Mensageiro/química , RNA Mensageiro/metabolismo , Ubiquitina/metabolismo , Proteínas ELAV/química , Humanos , Imunoprecipitação/métodos , RNA Antissenso/metabolismo , RNA Mensageiro/genética , Transcriptoma
11.
Retrovirology ; 6: 18, 2009 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-19220914

RESUMO

BACKGROUND: RNA interference is a gene regulatory mechanism that employs small RNA molecules such as microRNA. Previous work has shown that HIV-1 produces TAR viral microRNA. Here we describe the effects of the HIV-1 TAR derived microRNA on cellular gene expression. RESULTS: Using a variation of standard techniques we have cloned and sequenced both the 5' and 3' arms of the TAR miRNA. We show that expression of the TAR microRNA protects infected cells from apoptosis and acts by down-regulating cellular genes involved in apoptosis. Specifically, the microRNA down-regulates ERCC1 and IER3, protecting the cell from apoptosis. Comparison to our cloned sequence reveals possible target sites for the TAR miRNA as well. CONCLUSION: The TAR microRNA is expressed in all stages of the viral life cycle, can be detected in latently infected cells, and represents a mechanism wherein the virus extends the life of the infected cell for the purpose of increasing viral replication.


Assuntos
Apoptose/fisiologia , Regulação da Expressão Gênica , Repetição Terminal Longa de HIV/fisiologia , HIV-1/metabolismo , MicroRNAs/metabolismo , Sequência de Bases , Caspase 3/metabolismo , Linhagem Celular , Proteínas de Ligação a DNA/metabolismo , Endonucleases/metabolismo , Infecções por HIV/metabolismo , Infecções por HIV/virologia , Células HeLa , Interações Hospedeiro-Patógeno , Humanos , MicroRNAs/química , Ribonuclease III/metabolismo , Alinhamento de Sequência , Células U937
12.
Expert Rev Proteomics ; 5(3): 507-28, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18532916

RESUMO

Overall changes in the host cellular proteome upon retroviral infection intensify from the initial entry of the virus to the incorporation of viral DNA into the host genome, and finally to the consistent latent state of infection. The host cell reacts to both the entry of viral elements and the manipulation of host cellular machinery, resulting in a cascade of signaling events and pathway activation. Cell type- and tissue-specific responses are also characteristic of infection and can be classified based on the differential expression of genes and proteins between normal and disease states. The characterization of differentially expressed proteins upon infection is also critical in identifying potential biomarkers within infected bodily fluids. Biomarkers can be used to monitor the progression of infection, track the effectiveness of specific treatments and characterize the mechanisms of disease pathogenesis. Standard proteomic approaches have been applied to monitor the changes in global protein expression and localization in infected cells, tissues and fluids. Here we report on recent investigations into the characterization of proteomes in response to retroviral infection.


Assuntos
Sobrevivência Celular , Proteômica , Retroviridae/metabolismo , Proteínas Virais/metabolismo , Replicação Viral , Humanos , Retroviridae/fisiologia
13.
BMC Mol Biol ; 8: 63, 2007 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-17663774

RESUMO

BACKGROUND: RNA interference (RNAi) is a regulatory mechanism conserved in higher eukaryotes. The RNAi pathway generates small interfering RNA (siRNA) or micro RNA (miRNA) from either long double stranded stretches of RNA or RNA hairpins, respectively. The siRNA or miRNA then guides an effector complex to a homologous sequence of mRNA and regulates suppression of gene expression through one of several mechanisms. The suppression of gene expression through these mechanisms serves to regulate endogenous gene expression and protect the cell from foreign nucleic acids. There is growing evidence that many viruses have developed in the context of RNAi and express either a suppressor of RNAi or their own viral miRNA. RESULTS: In this study we investigated the possibility that the HIV-1 TAR element, a hairpin structure of ~50 nucleotides found at the 5' end of the HIV viral mRNA, is recognized by the RNAi machinery and processed to yield a viral miRNA. We show that the protein Dicer, the enzyme responsible for cleaving miRNA and siRNA from longer RNA sequences, is expressed in CD4+ T-cells. Interestingly, the level of expression of Dicer in monocytes is sub-optimal, suggesting a possible role for RNAi in maintaining latency in T-cells. Using a biotin labeled TAR element we demonstrate that Dicer binds to this structure. We show that recombinant Dicer is capable of cleaving the TAR element in vitro and that TAR derived miRNA is present in HIV-1 infected cell lines and primary T-cell blasts. Finally, we show that a TAR derived miRNA is capable of regulating viral gene expression and may be involved in repressing gene expression through transcriptional silencing. CONCLUSION: HIV-1 TAR element is processed by the Dicer enzyme to create a viral miRNA. This viral miRNA is detectable in infected cells and appears to contribute to viral latency.


Assuntos
RNA Helicases DEAD-box/metabolismo , Endorribonucleases/metabolismo , Repetição Terminal Longa de HIV/genética , HIV-1/genética , MicroRNAs/metabolismo , Western Blotting , Antígenos CD4/metabolismo , Linhagem Celular , Células Cultivadas , Montagem e Desmontagem da Cromatina , Imunoprecipitação da Cromatina , RNA Helicases DEAD-box/genética , Endorribonucleases/genética , Regulação Viral da Expressão Gênica , HIV-1/crescimento & desenvolvimento , HIV-1/metabolismo , Humanos , Células Jurkat , Luciferases/genética , Luciferases/metabolismo , MicroRNAs/genética , Mutação , Ligação Proteica , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , RNA Viral/genética , RNA Viral/metabolismo , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Ribonuclease III , Linfócitos T/metabolismo , Linfócitos T/virologia , Células U937
14.
Appl Environ Microbiol ; 72(7): 4638-47, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16820455

RESUMO

This study characterizes the interaction between Campylobacter jejuni and the 16 phages used in the United Kingdom typing scheme by screening spontaneous mutants of the phage-type strains and transposon mutants of the sequenced strain NCTC 11168. We show that the 16 typing phages fall into four groups based on their patterns of activity against spontaneous mutants. Screens of transposon and defined mutants indicate that the phage-bacterium interaction for one of these groups appears to involve the capsular polysaccharide (CPS), while two of the other three groups consist of flagellatropic phages. The expression of CPS and flagella is potentially phase variable in C. jejuni, and the implications of these findings for typing and intervention strategies are discussed.


Assuntos
Cápsulas Bacterianas/metabolismo , Tipagem de Bacteriófagos , Bacteriófagos/fisiologia , Campylobacter jejuni/crescimento & desenvolvimento , Campylobacter jejuni/virologia , Flagelos/metabolismo , Animais , Técnicas de Tipagem Bacteriana , Campylobacter jejuni/classificação , Campylobacter jejuni/genética , Elementos de DNA Transponíveis , Humanos , Lisogenia , Mutação , Fenótipo
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