Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 8 de 8
Filtrar
1.
Artigo em Inglês | MEDLINE | ID: mdl-34200176

RESUMO

Prenatal exposure to bisphenol A (BPA) may increase the risk of abnormal birth outcomes, and DNA methylation might mediate these adverse effects. This study aimed to investigate the effects of maternal BPA exposure on maternal and fetal DNA methylation levels and explore whether epigenetic changes are related to the associations between BPA and low birth weight. We collected urine and blood samples originating from 162 mother-infant pairs in a Taiwanese cohort study. We measured DNA methylation using the Illumina Infinium HumanMethylation 450 BeadChip in 34 maternal blood samples with high and low BPA levels based on the 75th percentile level (9.5 µg/g creatinine). Eighty-seven CpGs with the most differentially methylated probes possibly interacting with BPA exposure or birth weight were selected using two multiple regression models. Ingenuity pathway analysis (IPA) was utilized to narrow down 18 candidate CpGs related to disease categories, including developmental disorders, skeletal and muscular disorders, skeletal and muscular system development, metabolic diseases, and lipid metabolism. We then validated these genes by pyrosequencing, and 8 CpGs met the primer design score requirements in 82 cord blood samples. The associations among low birth weight, BPA exposure, and DNA methylation were analyzed. Exposure to BPA was associated with low birth weight. Analysis of the epigenome-wide findings did not show significant associations between BPA and DNA methylation in cord blood of the 8 CpGs. However, the adjusted odds ratio for the dehydrogenase/reductase member 9 (DHRS9) gene, at the 2nd CG site, in the hypermethylated group was significantly associated with low birth weight. These results support a role of BPA, and possibly DHRS9 methylation, in fetal growth. However, additional studies with larger sample sizes are warranted.


Assuntos
Metilação de DNA , Efeitos Tardios da Exposição Pré-Natal , Compostos Benzidrílicos/toxicidade , Peso ao Nascer , Estudos de Coortes , Feminino , Humanos , Recém-Nascido de Baixo Peso , Recém-Nascido , Exposição Materna/efeitos adversos , Fenóis , Projetos Piloto , Gravidez , Efeitos Tardios da Exposição Pré-Natal/genética , Taiwan/epidemiologia
2.
BMC Genomics ; 19(Suppl 2): 103, 2018 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-29764375

RESUMO

BACKGROUND: Aquatic animals have great economic and ecological importance. Among them, non-model organisms have been studied regarding eco-toxicity, stress biology, and environmental adaptation. Due to recent advances in next-generation sequencing techniques, large amounts of RNA-seq data for aquatic animals are publicly available. However, currently there is no comprehensive resource exist for the analysis, unification, and integration of these datasets. This study utilizes computational approaches to build a new resource of transcriptomic maps for aquatic animals. This aquatic animal transcriptome map database dbATM provides de novo assembly of transcriptome, gene annotation and comparative analysis of more than twenty aquatic organisms without draft genome. RESULTS: To improve the assembly quality, three computational tools (Trinity, Oases and SOAPdenovo-Trans) were employed to enhance individual transcriptome assembly, and CAP3 and CD-HIT-EST software were then used to merge these three assembled transcriptomes. In addition, functional annotation analysis provides valuable clues to gene characteristics, including full-length transcript coding regions, conserved domains, gene ontology and KEGG pathways. Furthermore, all aquatic animal genes are essential for comparative genomics tasks such as constructing homologous gene groups and blast databases and phylogenetic analysis. CONCLUSION: In conclusion, we establish a resource for non model organism aquatic animals, which is great economic and ecological importance and provide transcriptomic information including functional annotation and comparative transcriptome analysis. The database is now publically accessible through the URL http://dbATM.mbc.nctu.edu.tw/ .


Assuntos
Organismos Aquáticos/genética , Perfilação da Expressão Gênica/métodos , Genômica/métodos , Animais , Bases de Dados Genéticas , Redes Reguladoras de Genes , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Anotação de Sequência Molecular , Filogenia , Análise de Sequência de RNA/métodos , Software
3.
Int J Mol Sci ; 19(1)2017 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-29283424

RESUMO

Gastric cancer (GC) is the second most frequent cause of cancer-related deaths worldwide. MicroRNAs are single-stranded RNA molecules of 21-23 nucleotides that regulate target gene expression through specific base-pairing interactions between miRNA and untranslated regions of targeted mRNAs. In this study, we generated a multistep approach for the integrated analysis of miRNA and mRNA expression. First, both miRNA and mRNA expression profiling datasets in gastric cancer from the Gene Expression Omnibus (GEO) and The Cancer Genome Atlas (TCGA) identified 79 and 1042 differentially expressed miRNAs and mRNAs, respectively, in gastric cancer. Second, inverse correlations between miRNA and mRNA expression levels identified 3206 miRNA-mRNA pairs combined with 79 dysregulated miRNAs and their 774 target mRNAs predicted by three prediction tools, miRanda, PITA, and RNAhybrid. Additionally, miR-204, which was found to be down-regulated in gastric cancer, was ectopically over-expressed in the AGS gastric cancer cell line and all down-regulated targets were identified by RNA sequencing (RNA-seq) analysis. Over-expression of miR-204 reduced the gastric cancer cell proliferation and suppressed the expression of three targets which were validated by qRT-PCR and luciferase assays. For the first time, we identified that CKS1B, CXCL1, and GPRC5A are putative targets of miR-204 and elucidated that miR-204 acted as potential tumor suppressor and, therefore, are useful as a promising therapeutic target for gastric cancer.


Assuntos
Quinases relacionadas a CDC2 e CDC28/genética , Quimiocina CXCL1/genética , Regulação Neoplásica da Expressão Gênica , MicroRNAs/genética , Receptores Acoplados a Proteínas G/genética , Neoplasias Gástricas/genética , Atlas como Assunto , Sequência de Bases , Sítios de Ligação , Quinases relacionadas a CDC2 e CDC28/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Quimiocina CXCL1/metabolismo , Bases de Dados Genéticas , Perfilação da Expressão Gênica , Redes Reguladoras de Genes , Genes Reporter , Humanos , Luciferases/genética , Luciferases/metabolismo , MicroRNAs/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Análise de Sequência de RNA , Transdução de Sinais , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patologia
4.
BMC Genomics ; 17 Suppl 1: 13, 2016 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-26818233

RESUMO

BACKGROUND: Anguilla japonica (Japanese eel) is currently one of the most important research subjects in eastern Asia aquaculture. Enigmatic life cycle of the organism makes study of artificial reproduction extremely limited. Henceforth genomic and transcriptomic resources of eels are urgently needed to help solving the problems surrounding this organism across multiple fields. We hereby provide a reconstructed transcriptome from deep sequencing of juvenile (glass eels) whole body samples. The provided expressed sequence tags were used to annotate the currently available draft genome sequence. Homologous information derived from the annotation result was applied to improve the group of scaffolds into available linkage groups. RESULTS: With the transcriptome sequence data combined with publicly available expressed sequence tags evidences, 18,121 genes were structurally and functionally annotated on the draft genome. Among them, 3,921 genes were located in the 19 linkage groups. 137 scaffolds covering 13 million bases were grouped into the linkage groups in additional to the original partial linkage groups, increasing the linkage group coverage from 13 to 14%. CONCLUSIONS: This annotation provide information of the coding regions of the genes supported by transcriptome based evidence. The derived homologous evidences pave the way for phylogenetic analysis of important genetic traits and the improvement of the genome assembly.


Assuntos
Anguilla/genética , Genoma , Animais , Mapeamento Cromossômico , Peixes/genética , Ligação Genética , Sequenciamento de Nucleotídeos em Larga Escala , Filogenia , Polimorfismo de Nucleotídeo Único , Receptores Citoplasmáticos e Nucleares/classificação , Receptores Citoplasmáticos e Nucleares/genética , Análise de Sequência de RNA , Fatores de Transcrição/classificação , Fatores de Transcrição/genética
5.
Sci Rep ; 5: 10680, 2015 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-26033187

RESUMO

The purpose of this study was to identify the dysregulated genes involved in the tumorigenesis and progression of endometrial endometrioid adenocarcinoma (EEC), and their possible mechanisms. Endometrial specimens including normal endometrial tissues, atypical endometrial hyperplasia, and EEC were analyzed. The expression profiles were compared using GeneChip Array. The gene expression levels were determined by real-time RT-PCR in the training and testing sets to correlate the clinico-pathological parameters of EEC. Immunoblotting, in vitro cell migration and invasion assays were performed in human endometrial cancer cell lines and their transfectants. In microarray analysis, seven dysregulated genes were identified. Only the levels of urokinase-type plasminogen activator (uPA) were higher in EEC with deep myometrial invasion, positive lympho-vascular space invasion, lymph node metastasis, and advanced stages. After multivariate analysis, uPA was the only independent poor prognostic factor for disease-free survival in the EEC patients (hazard ratio: 4.65, p = 0.03). uPA may enhance the migratory and invasive capabilities of endometrial tumor cells by the phosphorylation of ERK1/2, Akt and p38 molecules. uPA is a dysregulated gene involved in the tumorigenesis, bio-pathological features and outcomes of EEC. uPA may be a potential molecule and target for the detection and treatment of EEC.


Assuntos
Transformação Celular Neoplásica/genética , Neoplasias do Endométrio/genética , Neoplasias do Endométrio/patologia , Ativador de Plasminogênio Tipo Uroquinase/genética , Adulto , Idoso , Linhagem Celular Tumoral , Movimento Celular , Transformação Celular Neoplásica/metabolismo , Análise por Conglomerados , Neoplasias do Endométrio/metabolismo , Neoplasias do Endométrio/mortalidade , Feminino , Perfilação da Expressão Gênica , Humanos , Sistema de Sinalização das MAP Quinases , Pessoa de Meia-Idade , Gradação de Tumores , Invasividade Neoplásica , Metástase Neoplásica , Estadiamento de Neoplasias , Pró-Colágeno-Lisina 2-Oxoglutarato 5-Dioxigenase/genética , Pró-Colágeno-Lisina 2-Oxoglutarato 5-Dioxigenase/metabolismo , Prognóstico , Proteínas Proto-Oncogênicas c-akt/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reprodutibilidade dos Testes , Transdução de Sinais , Ativador de Plasminogênio Tipo Uroquinase/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
6.
Nucleic Acids Res ; 43(Database issue): D856-61, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25398901

RESUMO

We present MethHC (http://MethHC.mbc.nctu.edu.tw), a database comprising a systematic integration of a large collection of DNA methylation data and mRNA/microRNA expression profiles in human cancer. DNA methylation is an important epigenetic regulator of gene transcription, and genes with high levels of DNA methylation in their promoter regions are transcriptionally silent. Increasing numbers of DNA methylation and mRNA/microRNA expression profiles are being published in different public repositories. These data can help researchers to identify epigenetic patterns that are important for carcinogenesis. MethHC integrates data such as DNA methylation, mRNA expression, DNA methylation of microRNA gene and microRNA expression to identify correlations between DNA methylation and mRNA/microRNA expression from TCGA (The Cancer Genome Atlas), which includes 18 human cancers in more than 6000 samples, 6548 microarrays and 12 567 RNA sequencing data.


Assuntos
Metilação de DNA , Bases de Dados Genéticas , Neoplasias/genética , Transcriptoma , Humanos , Internet , MicroRNAs/metabolismo , Neoplasias/metabolismo , RNA Mensageiro/metabolismo
7.
Cancer Med ; 3(4): 878-88, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24902858

RESUMO

Gastric cancer (GC) is the second leading cause of global cancer mortality. Most GC patients are diagnosed with advanced-stage disease and show extremely poor prognosis. All of the GC research has a common interest to search for the specific and sensitive biomarkers for early diagnosis of GC. Number of microRNAs play important role in GC. We carried out a systematic review of published miRNA profiling studies that compared the miRNA expression profiles between GC tissues and paired noncancerous gastric tissue. A vote-counting strategy was followed with the collection of information like total number of studies reporting differential expression of miRNA, total number of tissue samples used in the studies, direction of differential expression and fold change. A total of 352 differentially expressed microRNAs were reported in the 14 microRNA expression profiling studies that compared GC tissues with normal tissues with 120 microRNAs reported at least in two studies. In the group of consistently reported microRNAs, miR-21 was reported upregulated in 10 studies followed by miR-25, miR-92, and miR-223 upregulated in eight studies. MiR-375 and miR-148a were found downregulated in six and five studies, respectively, followed by miR-638 in four studies. MiR-107 and miR-103 were reported in nine and eight studies, respectively, but their expression were inconsistent. From this study, the most consistently reported upregulated microRNA was found to be miR-21. This systematic review study of human GC microRNA expression profiling studies would provide information on microRNAs with potential role as the biomarkers in gastric cancer.


Assuntos
Biomarcadores Tumorais/metabolismo , MicroRNAs/metabolismo , Neoplasias Gástricas/metabolismo , Transcriptoma , Animais , Biomarcadores Tumorais/genética , Detecção Precoce de Câncer , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , MicroRNAs/genética , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/genética
8.
BMC Bioinformatics ; 12: 300, 2011 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-21791068

RESUMO

BACKGROUND: MicroRNAs (miRNAs) are small non-coding RNA molecules that are ~22-nt-long sequences capable of suppressing protein synthesis. Previous research has suggested that miRNAs regulate 30% or more of the human protein-coding genes. The aim of this work is to consider various analyzing scenarios in the identification of miRNA-target interactions, as well as to provide an integrated system that will aid in facilitating investigation on the influence of miRNA targets by alternative splicing and the biological function of miRNAs in biological pathways. RESULTS: This work presents an integrated system, miRTar, which adopts various analyzing scenarios to identify putative miRNA target sites of the gene transcripts and elucidates the biological functions of miRNAs toward their targets in biological pathways. The system has three major features. First, the prediction system is able to consider various analyzing scenarios (1 miRNA:1 gene, 1:N, N:1, N:M, all miRNAs:N genes, and N miRNAs: genes involved in a pathway) to easily identify the regulatory relationships between interesting miRNAs and their targets, in 3'UTR, 5'UTR and coding regions. Second, miRTar can analyze and highlight a group of miRNA-regulated genes that participate in particular KEGG pathways to elucidate the biological roles of miRNAs in biological pathways. Third, miRTar can provide further information for elucidating the miRNA regulation, i.e., miRNA-target interactions, affected by alternative splicing. CONCLUSIONS: In this work, we developed an integrated resource, miRTar, to enable biologists to easily identify the biological functions and regulatory relationships between a group of known/putative miRNAs and protein coding genes. miRTar is now available at http://miRTar.mbc.nctu.edu.tw/.


Assuntos
MicroRNAs/genética , RNA Mensageiro/genética , Regiões 3' não Traduzidas , Regiões 5' não Traduzidas , Regulação da Expressão Gênica , Humanos , MicroRNAs/metabolismo , Biossíntese de Proteínas
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...