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1.
Genetics ; 227(1)2024 05 07.
Artículo en Inglés | MEDLINE | ID: mdl-38573366

RESUMEN

WormBase has been the major repository and knowledgebase of information about the genome and genetics of Caenorhabditis elegans and other nematodes of experimental interest for over 2 decades. We have 3 goals: to keep current with the fast-paced C. elegans research, to provide better integration with other resources, and to be sustainable. Here, we discuss the current state of WormBase as well as progress and plans for moving core WormBase infrastructure to the Alliance of Genome Resources (the Alliance). As an Alliance member, WormBase will continue to interact with the C. elegans community, develop new features as needed, and curate key information from the literature and large-scale projects.


Asunto(s)
Caenorhabditis elegans , Caenorhabditis elegans/genética , Animales , Bases de Datos Genéticas , Genoma de los Helmintos , Genómica/métodos
2.
Viruses ; 14(5)2022 04 24.
Artículo en Inglés | MEDLINE | ID: mdl-35632628

RESUMEN

A human betaretrovirus (HBRV) has been linked with the autoimmune liver disease, primary biliary cholangitis (PBC), and various cancers, including breast cancer and lymphoma. HBRV is closely related to the mouse mammary tumor virus, and represents the only exogenous betaretrovirus characterized in humans to date. Evidence of infection in patients with PBC has been demonstrated through the identification of proviral integration sites in lymphoid tissue, the major reservoir of infection, as well as biliary epithelium, which is the site of the disease process. Accordingly, we tested the hypothesis that patients with PBC harbor a transmissible betaretrovirus by co-cultivation of PBC patients' lymph node homogenates with the HS578T breast cancer line. Because of the low level of HBRV replication, betaretrovirus producing cells were subcloned to optimize viral isolation and production. Evidence of infection was provided by electron microscopy, RT-PCR, in situ hybridization, cloning of the HBRV proviral genome and demonstration of more than 3400 integration sites. Further evidence of viral transmissibility was demonstrated by infection of biliary epithelial cells. While HBRV did not show a preference for integration proximal to specific genomic features, analyses of common insertion sites revealed evidence of integration proximal to cancer associated genes. These studies demonstrate the isolation of HBRV with features similar to mouse mammary tumor virus and confirm that patients with PBC display evidence of a transmissible viral infection.


Asunto(s)
Betaretrovirus , Neoplasias de la Mama , Cirrosis Hepática Biliar , Animales , Femenino , Humanos , Cirrosis Hepática Biliar/etiología , Virus del Tumor Mamario del Ratón/genética , Ratones , Provirus/genética
3.
Genetics ; 220(4)2022 04 04.
Artículo en Inglés | MEDLINE | ID: mdl-35134929

RESUMEN

WormBase (www.wormbase.org) is the central repository for the genetics and genomics of the nematode Caenorhabditis elegans. We provide the research community with data and tools to facilitate the use of C. elegans and related nematodes as model organisms for studying human health, development, and many aspects of fundamental biology. Throughout our 22-year history, we have continued to evolve to reflect progress and innovation in the science and technologies involved in the study of C. elegans. We strive to incorporate new data types and richer data sets, and to provide integrated displays and services that avail the knowledge generated by the published nematode genetics literature. Here, we provide a broad overview of the current state of WormBase in terms of data type, curation workflows, analysis, and tools, including exciting new advances for analysis of single-cell data, text mining and visualization, and the new community collaboration forum. Concurrently, we continue the integration and harmonization of infrastructure, processes, and tools with the Alliance of Genome Resources, of which WormBase is a founding member.


Asunto(s)
Caenorhabditis , Nematodos , Animales , Caenorhabditis/genética , Caenorhabditis elegans/genética , Bases de Datos Genéticas , Genoma , Genómica , Humanos , Nematodos/genética
4.
Artículo en Inglés | MEDLINE | ID: mdl-33688250

RESUMEN

PURPOSE: Forkhead box Q1 (FOXQ1) has been shown to contribute to the development and progression of cancers, including ovarian and breast cancer (BC). However, research exploring FOXQ1 expression, copy number variation (CNV), and prognostic value across different BC subtypes is limited. Our purpose was to evaluate FOXQ1 mRNA expression, CNV, and prognostic value across BC subtypes. MATERIALS AND METHODS: We determined FOXQ1 expression and CNV in BC patient tumors using RT-qPCR and qPCR, respectively. We also analyzed FOXQ1 expression and CNV in BC cell lines in the CCLE database using K-means clustering. The prognostic value of FOXQ1 expression in the TCGA-BRCA database was assessed using univariate and multivariate Cox's regression analysis as well as using the online tools OncoLnc, GEPIA, and UALCAN. RESULTS: Our analyses reveal that FOXQ1 mRNA is differentially expressed between different subtypes of BC and is significantly decreased in luminal BC and HER2 patients when compared to normal breast tissue samples. Furthermore, analysis of BC cell lines showed that FOXQ1 mRNA expression was independent of CNV. Moreover, patients with low FOXQ1 mRNA expression had significantly poorer overall survival compared to those with high FOXQ1 mRNA expression. Finally, low FOXQ1 expression had a critical impact on the prognostic values of BC patients and was an independent predictor of overall survival when it was adjusted for BC subtypes and to two other FOX genes, FOXF2 and FOXM1. CONCLUSION: Our study reveals for the first time that FOXQ1 is differentially expressed across BC subtypes and that low expression of FOXQ1 is indicative of poor prognosis in patients with BC.

5.
Nucleic Acids Res ; 48(D1): D762-D767, 2020 01 08.
Artículo en Inglés | MEDLINE | ID: mdl-31642470

RESUMEN

WormBase (https://wormbase.org/) is a mature Model Organism Information Resource supporting researchers using the nematode Caenorhabditis elegans as a model system for studies across a broad range of basic biological processes. Toward this mission, WormBase efforts are arranged in three primary facets: curation, user interface and architecture. In this update, we describe progress in each of these three areas. In particular, we discuss the status of literature curation and recently added data, detail new features of the web interface and options for users wishing to conduct data mining workflows, and discuss our efforts to build a robust and scalable architecture by leveraging commercial cloud offerings. We conclude with a description of WormBase's role as a founding member of the nascent Alliance of Genome Resources.


Asunto(s)
Caenorhabditis elegans/genética , Bases de Datos Genéticas , Genes de Helminto , Animales , Minería de Datos , Genómica , Internet , Interfaz Usuario-Computador
6.
Lab Invest ; 98(6): 839, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29520053

RESUMEN

Figure 2 is incorrect in the original version of this article. The correct figure 2 is provided below.

7.
Lab Invest ; 98(4): 403-413, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29339834

RESUMEN

A variety of laboratory methods are available for the detection of deletions of tumor suppressor genes and losses of their proteins. The clinical utility of fluorescence in situ hybridization (FISH) for the identification of deletions of tumor suppressor genes has previously been limited by difficulties in the interpretation of FISH signal patterns. The first deletion FISH assays using formalin-fixed paraffin-embedded tissue sections had to deal with a significant background level of signal losses affecting nuclei that are truncated by the cutting process of slide preparation. Recently, more efficient probe designs, incorporating probes adjacent to the tumor suppressor gene of interest, have increased the accuracy of FISH deletion assays so that true chromosomal deletions can be readily distinguished from the false signal losses caused by sectioning artifacts. This mini-review discusses the importance of recurrent tumor suppressor gene deletions in human cancer and reviews the common FISH methods being used to detect the genomic losses encountered in clinical specimens. The use of new probe designs to recognize truncation artifacts is illustrated with a four-color PTEN FISH set optimized for prostate cancer tissue sections. Data are presented to show that when section thickness is reduced, the frequency of signal truncation losses is increased. We also provide some general guidelines that will help pathologists and cytogeneticists run routine deletion FISH assays and recognize sectioning artifacts. Finally, we summarize how recently developed sequence-based approaches are being used to identify recurrent deletions using small DNA samples from tumors.


Asunto(s)
Eliminación de Gen , Genes Supresores de Tumor , Hibridación Fluorescente in Situ/métodos , Neoplasias/genética , Humanos , Neoplasias/patología
8.
Nucleic Acids Res ; 46(D1): D869-D874, 2018 01 04.
Artículo en Inglés | MEDLINE | ID: mdl-29069413

RESUMEN

WormBase (http://www.wormbase.org) is an important knowledge resource for biomedical researchers worldwide. To accommodate the ever increasing amount and complexity of research data, WormBase continues to advance its practices on data acquisition, curation and retrieval to most effectively deliver comprehensive knowledge about Caenorhabditis elegans, and genomic information about other nematodes and parasitic flatworms. Recent notable enhancements include user-directed submission of data, such as micropublication; genomic data curation and presentation, including additional genomes and JBrowse, respectively; new query tools, such as SimpleMine, Gene Enrichment Analysis; new data displays, such as the Person Lineage browser and the Summary of Ontology-based Annotations. Anticipating more rapid data growth ahead, WormBase continues the process of migrating to a cutting-edge database technology to achieve better stability, scalability, reproducibility and a faster response time. To better serve the broader research community, WormBase, with five other Model Organism Databases and The Gene Ontology project, have begun to collaborate formally as the Alliance of Genome Resources.


Asunto(s)
Bases de Datos Genéticas , Genoma , Nematodos/genética , Animales , Caenorhabditis/genética , Caenorhabditis elegans/genética , Curaduría de Datos , Minería de Datos , Conjuntos de Datos como Asunto , Modelos Animales de Enfermedad , Predicción , Ontología de Genes , Humanos , Almacenamiento y Recuperación de la Información , Platelmintos/genética , Edición , Interferencia de ARN , Alineación de Secuencia , Interfaz Usuario-Computador , Navegador Web
9.
Nucleic Acids Res ; 44(D1): D774-80, 2016 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-26578572

RESUMEN

WormBase (www.wormbase.org) is a central repository for research data on the biology, genetics and genomics of Caenorhabditis elegans and other nematodes. The project has evolved from its original remit to collect and integrate all data for a single species, and now extends to numerous nematodes, ranging from evolutionary comparators of C. elegans to parasitic species that threaten plant, animal and human health. Research activity using C. elegans as a model system is as vibrant as ever, and we have created new tools for community curation in response to the ever-increasing volume and complexity of data. To better allow users to navigate their way through these data, we have made a number of improvements to our main website, including new tools for browsing genomic features and ontology annotations. Finally, we have developed a new portal for parasitic worm genomes. WormBase ParaSite (parasite.wormbase.org) contains all publicly available nematode and platyhelminth annotated genome sequences, and is designed specifically to support helminth genomic research.


Asunto(s)
Caenorhabditis elegans/genética , Bases de Datos Genéticas , Genoma de los Helmintos , Genómica , Nematodos/genética , Animales , Genes de Helminto , Anotación de Secuencia Molecular , Platelmintos/genética , Programas Informáticos
10.
Bioinformatics ; 30(5): 712-8, 2014 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-24149051

RESUMEN

MOTIVATION: We introduce a novel method for visualizing high dimensional data via a discrete dynamical system. This method provides a 2D representation of the relationship between subjects according to a set of variables without geometric projections, transformed axes or principal components. The algorithm exploits a memory-type mechanism inherent in a certain class of discrete dynamical systems collectively referred to as the chaos game that are closely related to iterative function systems. The goal of the algorithm was to create a human readable representation of high dimensional patient data that was capable of detecting unrevealed subclusters of patients from within anticipated classifications. This provides a mechanism to further pursue a more personalized exploration of pathology when used with medical data. For clustering and classification protocols, the dynamical system portion of the algorithm is designed to come after some feature selection filter and before some model evaluation (e.g. clustering accuracy) protocol. In the version given here, a univariate features selection step is performed (in practice more complex feature selection methods are used), a discrete dynamical system is driven by this reduced set of variables (which results in a set of 2D cluster models), these models are evaluated for their accuracy (according to a user-defined binary classification) and finally a visual representation of the top classification models are returned. Thus, in addition to the visualization component, this methodology can be used for both supervised and unsupervised machine learning as the top performing models are returned in the protocol we describe here. RESULTS: Butterfly, the algorithm we introduce and provide working code for, uses a discrete dynamical system to classify high dimensional data and provide a 2D representation of the relationship between subjects. We report results on three datasets (two in the article; one in the appendix) including a public lung cancer dataset that comes along with the included Butterfly R package. In the included R script, a univariate feature selection method is used for the dimension reduction step, but in the future we wish to use a more powerful multivariate feature reduction method based on neural networks (Kriesel, 2007). AVAILABILITY AND IMPLEMENTATION: A script written in R (designed to run on R studio) accompanies this article that implements this algorithm and is available at http://butterflygeraci.codeplex.com/. For details on the R package or for help installing the software refer to the accompanying document, Supporting Material and Appendix.


Asunto(s)
Algoritmos , Inteligencia Artificial , Clasificación/métodos , Análisis por Conglomerados , Gráficos por Computador , Femenino , Perfilación de la Expresión Génica , Humanos , Neoplasias Pulmonares/clasificación , Neoplasias Pulmonares/genética , Modelos Teóricos , Neoplasias Ováricas/clasificación , Neoplasias Ováricas/genética , Programas Informáticos
11.
BMC Cancer ; 13: 549, 2013 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-24237932

RESUMEN

BACKGROUND: Resistance to platinum-based chemotherapy remains a major impediment in the treatment of serous epithelial ovarian cancer. The objective of this study was to use gene expression profiling to delineate major deregulated pathways and biomarkers associated with the development of intrinsic chemotherapy resistance upon exposure to standard first-line therapy for ovarian cancer. METHODS: The study cohort comprised 28 patients divided into two groups based on their varying sensitivity to first-line chemotherapy using progression free survival (PFS) as a surrogate of response. All 28 patients had advanced stage, high-grade serous ovarian cancer, and were treated with standard platinum-based chemotherapy. Twelve patient tumours demonstrating relative resistance to platinum chemotherapy corresponding to shorter PFS (< eight months) were compared to sixteen tumours from platinum-sensitive patients (PFS > eighteen months). Whole transcriptome profiling was performed using an Affymetrix high-resolution microarray platform to permit global comparisons of gene expression profiles between tumours from the resistant group and the sensitive group. RESULTS: Microarray data analysis revealed a set of 204 discriminating genes possessing expression levels which could influence differential chemotherapy response between the two groups. Robust statistical testing was then performed which eliminated a dependence on the normalization algorithm employed, producing a restricted list of differentially regulated genes, and which found IGF1 to be the most strongly differentially expressed gene. Pathway analysis, based on the list of 204 genes, revealed enrichment in genes primarily involved in the IGF1/PI3K/NF κB/ERK gene signalling networks. CONCLUSIONS: This study has identified pathway specific prognostic biomarkers possibly underlying a differential chemotherapy response in patients undergoing standard platinum-based treatment of serous epithelial ovarian cancer. In addition, our results provide a pathway context for further experimental validations, and the findings are a significant step towards future therapeutic interventions.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Resistencia a Antineoplásicos/genética , Factor I del Crecimiento Similar a la Insulina/genética , FN-kappa B/genética , Neoplasias Glandulares y Epiteliales/tratamiento farmacológico , Neoplasias Glandulares y Epiteliales/genética , Neoplasias Ováricas/tratamiento farmacológico , Neoplasias Ováricas/genética , Fosfatidilinositol 3-Quinasas/genética , Anciano , Carcinoma Epitelial de Ovario , Análisis por Conglomerados , Femenino , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Redes Reguladoras de Genes , Humanos , Factor I del Crecimiento Similar a la Insulina/metabolismo , Persona de Mediana Edad , FN-kappa B/metabolismo , Clasificación del Tumor , Neoplasias Glandulares y Epiteliales/mortalidad , Neoplasias Glandulares y Epiteliales/patología , Neoplasias Ováricas/mortalidad , Neoplasias Ováricas/patología , Fosfatidilinositol 3-Quinasas/metabolismo , Reproducibilidad de los Resultados , Transducción de Señal , Resultado del Tratamiento
12.
Clin Chem ; 59(11): 1595-603, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23958847

RESUMEN

PURPOSE: Prostate-specific antigen testing has led to overtreatment of prostate cancer (PCa). Only a small subset of PCa patients will have an aggressive disease that requires intensive therapy, and there is currently no biomarker to predict disease aggressiveness at the time of surgery. MicroRNAs (miRNAs) are reported to be involved in PCa pathogenesis. METHODS: This study involved 105 participants. For the discovery phase, prostatectomy samples were dichotomized to high-risk (n = 27, biochemical failure <36 months after prostatectomy) and low-risk groups (n = 14, ≥ 36 months without biochemical failure). Expression of 754 mature miRNAs was compared between the 2 groups. Linear regression models were built to accurately predict biochemical failure risk. miRNA mimics were transfected into PCa model cell lines to test effects on proliferation and to deduce responding signaling pathways. RESULTS: We identified 25 differentially expressed miRNAs between the biochemical failure risk groups. Based on the expression of 2-3 miRNAs, 3 logistic regression models were developed, each with a high positive predictive value. Candidate miRNAs and the best-performing model were also verified on an independent PCa set. miRNA-152, featured in the models, was further investigated by using cell line models and was shown to affect cell proliferation. Predicted interaction between miR-152 and (mRNA)ERBB3 (erythroblastic leukemia viral oncogene homolog 3) was experimentally validated in vitro. CONCLUSIONS: miRNAs can help to predict biochemical failure risk at the time of prostatectomy.


Asunto(s)
MicroARNs/metabolismo , Recurrencia Local de Neoplasia/diagnóstico , Antígeno Prostático Específico/sangre , Neoplasias de la Próstata/diagnóstico , Línea Celular Tumoral , Proliferación Celular , Humanos , Modelos Logísticos , Masculino , MicroARNs/análisis , Recurrencia Local de Neoplasia/genética , Recurrencia Local de Neoplasia/metabolismo , Prostatectomía , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/metabolismo , Receptor ErbB-3/genética , Medición de Riesgo , Transcriptoma
13.
BMC Plant Biol ; 12: 175, 2012 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-23025749

RESUMEN

BACKGROUND: Thellungiella salsuginea is an important model plant due to its natural tolerance to abiotic stresses including salt, cold, and water deficits. Microarray and metabolite profiling have shown that Thellungiella undergoes stress-responsive changes in transcript and organic solute abundance when grown under controlled environmental conditions. However, few reports assess the capacity of plants to display stress-responsive traits in natural habitats where concurrent stresses are the norm. RESULTS: To determine whether stress-responsive changes observed in cabinet-grown plants are recapitulated in the field, we analyzed leaf transcript and metabolic profiles of Thellungiella growing in its native Yukon habitat during two years of contrasting meteorological conditions. We found 673 genes showing differential expression between field and unstressed, chamber-grown plants. There were comparatively few overlaps between genes expressed under field and cabinet treatment-specific conditions. Only 20 of 99 drought-responsive genes were expressed both in the field during a year of low precipitation and in plants subjected to drought treatments in cabinets. There was also a general pattern of lower abundance among metabolites found in field plants relative to control or stress-treated plants in growth cabinets. Nutrient availability may explain some of the observed differences. For example, proline accumulated to high levels in cold and salt-stressed cabinet-grown plants but proline content was, by comparison, negligible in plants at a saline Yukon field site. We show that proline accumulated in a stress-responsive manner in Thellungiella plants salinized in growth cabinets and in salt-stressed seedlings when nitrogen was provided at 1.0 mM. In seedlings grown on 0.1 mM nitrogen medium, the proline content was low while carbohydrates increased. The relatively higher content of sugar-like compounds in field plants and seedlings on low nitrogen media suggests that Thellungiella shows metabolic plasticity in response to environmental stress and that resource availability can influence the expression of stress tolerance traits under field conditions. CONCLUSION: Comparisons between Thellungiella plants responding to stress in cabinets and in their natural habitats showed differences but also overlap between transcript and metabolite profiles. The traits in common offer potential targets for improving crops that must respond appropriately to multiple, concurrent stresses.


Asunto(s)
Brassicaceae/genética , Metaboloma , Fenotipo , Estrés Fisiológico , Transcriptoma , Brassicaceae/crecimiento & desarrollo , Brassicaceae/metabolismo , Sequías , Ecosistema , Regulación de la Expresión Génica de las Plantas , Nitrógeno/metabolismo , Prolina/metabolismo , Salinidad , Cloruro de Sodio/metabolismo , Suelo/química , El Yukón
14.
FEMS Microbiol Ecol ; 82(2): 405-15, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22551442

RESUMEN

Osmotic stress can accompany increases in solute concentrations because of freezing or high-salt environments. Consequently, microorganisms from environments with a high-osmotic potential may exhibit cross-tolerance to freeze stress. To test this hypothesis, enrichments derived from the sediment and water of temperate lakes with a range of salt concentrations were subjected to multiple freeze-thaw cycles. Surviving isolates were identified and metagenomes were sampled prior to and following selection. Enrichments from alkali lakes were typically the most freeze-thaw resistant with only 100-fold losses in cell viability, and those from freshwater lakes were most susceptible, with cell numbers reduced at least 100,000-fold. Metagenomic analysis suggested that selection reduced assemblage diversity more in freshwater samples than in those from saline lakes. Survivors included known psychro-, halo- and alkali-tolerant bacteria. Characterization of freeze-thaw-resistant isolates from brine and alkali lakes showed that few isolates had ice-associating activities such as antifreeze or ice nucleation properties. However, all brine- and alkali-derived isolates had high intracellular levels of osmolytes and/or appeared more likely to form biofilms. Conversely, these phenotypes were infrequent amongst the freshwater-derived isolates. These observations are consistent with microbial cross-tolerance between osmotic and freeze-thaw stresses.


Asunto(s)
Bacterias/crecimiento & desarrollo , Lagos/microbiología , Metagenoma , Salinidad , Microbiología del Agua , Bacterias/clasificación , Bacterias/genética , Biopelículas , Crioprotectores , ADN Bacteriano/genética , Congelación , Hielo , Viabilidad Microbiana , Ósmosis , ARN Ribosómico 16S/genética , Agua/química
15.
BMC Cancer ; 12: 91, 2012 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-22429801

RESUMEN

BACKGROUND: The epithelial to mesenchymal transition (EMT) is a molecular process through which an epithelial cell undergoes transdifferentiation into a mesenchymal phenotype. The role of EMT in embryogenesis is well-characterized and increasing evidence suggests that elements of the transition may be important in other processes, including metastasis and drug resistance in various different cancers. METHODS: Agilent 4 × 44 K whole human genome arrays and selected reaction monitoring mass spectrometry were used to investigate mRNA and protein expression in A2780 cisplatin sensitive and resistant cell lines. Invasion and migration were assessed using Boyden chamber assays. Gene knockdown of snail and slug was done using targeted siRNA. Clinical relevance of the EMT pathway was assessed in a cohort of primary ovarian tumours using data from Affymetrix GeneChip Human Genome U133 plus 2.0 arrays. RESULTS: Morphological and phenotypic hallmarks of EMT were identified in the chemoresistant cells. Subsequent gene expression profiling revealed upregulation of EMT-related transcription factors including snail, slug, twist2 and zeb2. Proteomic analysis demonstrated up regulation of Snail and Slug as well as the mesenchymal marker Vimentin, and down regulation of E-cadherin, an epithelial marker. By reducing expression of snail and slug, the mesenchymal phenotype was largely reversed and cells were resensitized to cisplatin. Finally, gene expression data from primary tumours mirrored the finding that an EMT-like pathway is activated in resistant tumours relative to sensitive tumours, suggesting that the involvement of this transition may not be limited to in vitro drug effects. CONCLUSIONS: This work strongly suggests that genes associated with EMT may play a significant role in cisplatin resistance in ovarian cancer, therefore potentially leading to the development of predictive biomarkers of drug response or novel therapeutic strategies for overcoming drug resistance.


Asunto(s)
Antineoplásicos/uso terapéutico , Cisplatino/uso terapéutico , Resistencia a Antineoplásicos , Transición Epitelial-Mesenquimal/fisiología , Proteínas de Neoplasias/metabolismo , Neoplasias Ováricas/tratamiento farmacológico , Factores de Transcripción/metabolismo , Línea Celular Tumoral , Movimiento Celular , Proliferación Celular , Estudios de Cohortes , Femenino , Perfilación de la Expresión Génica , Humanos , Espectrometría de Masas/métodos , Invasividad Neoplásica , Proteínas de Neoplasias/genética , Neoplasias Ováricas/genética , Neoplasias Ováricas/metabolismo , Neoplasias Ováricas/patología , ARN Mensajero/metabolismo , Factores de Transcripción de la Familia Snail , Factores de Transcripción/genética
16.
Genes Chromosomes Cancer ; 51(2): 149-60, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22045666

RESUMEN

Deletion of PTEN at 10q23.3 occurs in ∼40% of human prostate cancers and is associated with aggressive metastatic potential, poor prognosis, and androgen-independence. This high frequency of recurrent PTEN deletions in prostate cancer suggests there may be unusual genomic features close to this locus that facilitate DNA alteration at 10q23.3. To explore possible mechanisms for deletions in the PTEN region, a meta-analysis of 311 published human genome array datasets was conducted and determined that the minimal prostate cancer-associated deletion at 10q23.3 corresponds to ∼2.06 MB region flanked by BMPR1A and FAS. On a separate cohort comprising an additional 330 tumors, four-color fluorescence in situ hybridization analysis using probes for BMPR1A, FAS, cen(10), and PTEN showed that 132 of 330 (40%) tumors had PTEN loss, 50 (15%) of which were homozygous losses (comprising in total 100 deletion events). Breakpoints between PTEN and BMPR1A or FAS were subsequently mapped in 100 homozygous and 82 hemizygous PTEN losses, revealing that 125/182 PTEN microdeletions occurred within the 940 kB interval between BMPR1A and PTEN. Furthermore, this breakpoint interval coincides with a repeat-rich region of 414 kB containing the SD17 and SD18 segmental duplications, which contain at least 13 homologous inverted repeat sequences. Together, these data suggest that a strong selective growth advantage for loss of PTEN and upregulation of PI3K/AKT, combined with the close proximity of PTEN to a large unstable segment of repeated DNA comprising SD17 and SD18, can lead to recurrent microdeletions of the PTEN gene in prostate cancer. © 2011 Wiley Periodicals, Inc.


Asunto(s)
Eliminación de Gen , Fosfohidrolasa PTEN/genética , Neoplasias de la Próstata/genética , Duplicaciones Segmentarias en el Genoma , Receptores de Proteínas Morfogenéticas Óseas de Tipo 1/genética , Puntos de Rotura del Cromosoma , Cromosomas Humanos Par 10 , Humanos , Hibridación Fluorescente in Situ , Interfase , Masculino , Clasificación del Tumor , Neoplasias de la Próstata/patología , Secuencias Repetitivas de Ácidos Nucleicos , Análisis de Matrices Tisulares
17.
Appl Environ Microbiol ; 77(15): 5361-9, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21666017

RESUMEN

Dehalococcoides spp. are an industrially relevant group of Chloroflexi bacteria capable of reductively dechlorinating contaminants in groundwater environments. Existing Dehalococcoides genomes revealed a high level of sequence identity within this group, including 98 to 100% 16S rRNA sequence identity between strains with diverse substrate specificities. Common molecular techniques for identification of microbial populations are often not applicable for distinguishing Dehalococcoides strains. Here we describe an oligonucleotide microarray probe set designed based on clustered Dehalococcoides genes from five different sources (strain DET195, CBDB1, BAV1, and VS genomes and the KB-1 metagenome). This "pangenome" probe set provides coverage of core Dehalococcoides genes as well as strain-specific genes while optimizing the potential for hybridization to closely related, previously unknown Dehalococcoides strains. The pangenome probe set was compared to probe sets designed independently for each of the five Dehalococcoides strains. The pangenome probe set demonstrated better predictability and higher detection of Dehalococcoides genes than strain-specific probe sets on nontarget strains with <99% average nucleotide identity. An in silico analysis of the expected probe hybridization against the recently released Dehalococcoides strain GT genome and additional KB-1 metagenome sequence data indicated that the pangenome probe set performs more robustly than the combined strain-specific probe sets in the detection of genes not included in the original design. The pangenome probe set represents a highly specific, universal tool for the detection and characterization of Dehalococcoides from contaminated sites. It has the potential to become a common platform for Dehalococcoides-focused research, allowing meaningful comparisons between microarray experiments regardless of the strain examined.


Asunto(s)
Técnicas de Tipificación Bacteriana/métodos , Chloroflexi/genética , Análisis de Secuencia por Matrices de Oligonucleótidos/métodos , Secuencia de Bases , ADN Bacteriano/análisis , ADN Bacteriano/genética , Familia de Multigenes , Hibridación de Ácido Nucleico/genética , Sondas de Oligonucleótidos/genética , Proteómica/métodos , ARN Ribosómico 16S/análisis , ARN Ribosómico 16S/genética , Alineación de Secuencia , Análisis de Secuencia de ADN
19.
Cancer Lett ; 273(2): 323-30, 2009 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-18823700

RESUMEN

Well-differentiated liposarcomas (WDLPS) and dedifferentiated liposarcomas are cytogenetically characterized by the presence of supernumerary ring or giant chromosomes containing amplified material from the 12q14-15 region. These chromosomes contain neocentromeres, which are able to bind the kinetochore proteins and to ensure a stable mitotic transmission although they do not show detectable alpha-satellite sequences. WDLPS is the sole solid tumor for which the presence of a neocentromere is a consistent and specific feature. By immunostaining with anti-centromere antibodies in combination with FISH analysis (immunoFISH) in four cases of WDLPS, we have shown that sequences from the region 12q14-21 region were not located at the neocentromere site. In addition, we have microdissected the neocentromeric region from a giant supernumerary chromosome in the 94T778 WDLPS cell line. By using immunoFISH and positional cloning we have shown that the neocentromere of this cell line originated from a region at 4p16.1, rich in AT sequences and in long interspersed nucleotide element (LINE)1, that was co-amplified with 12q14-15. We have observed that this 4p sequence was not involved in the neocentromere of the supernumerary giant chromosome present in the 93T449 WDLPS cell line derived from a metachronous recurrence of the same primary WDLPS than 94T778. Altogether, these results indicate that the neocentromeres in WDLPS originate from amplified chromosomal regions other than 12q14-15 and do not involve a specific and recurrent DNA sequence. These sequences might be activated for centromeric function by epigenetic mechanisms.


Asunto(s)
Centrómero/ultraestructura , Cromosomas/ultraestructura , Liposarcoma/genética , Línea Celular , Aberraciones Cromosómicas , Clonación Molecular , Humanos , Hibridación Fluorescente in Situ , Liposarcoma/patología , Elementos de Nucleótido Esparcido Largo , Metafase , Microdisección , Mitosis
20.
BMC Bioinformatics ; 7: 471, 2006 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-17062146

RESUMEN

BACKGROUND: There have been many algorithms and software programs implemented for the inference of multiple sequence alignments of protein and DNA sequences. The "true" alignment is usually unknown due to the incomplete knowledge of the evolutionary history of the sequences, making it difficult to gauge the relative accuracy of the programs. RESULTS: We tested nine of the most often used protein alignment programs and compared their results using sequences generated with the simulation software Simprot which creates known alignments under realistic and controlled evolutionary scenarios. We have simulated more than 30,000 alignment sets using various evolutionary histories in order to define strengths and weaknesses of each program tested. We found that alignment accuracy is extremely dependent on the number of insertions and deletions in the sequences, and that indel size has a weaker effect. We also considered benchmark alignments from the latest version of BAliBASE and the results relative to BAliBASE- and Simprot-generated data sets were consistent in most cases. CONCLUSION: Our results indicate that employing Simprot's simulated sequences allows the creation of a more flexible and broader range of alignment classes than the usual methods for alignment accuracy assessment. Simprot also allows for a quick and efficient analysis of a wider range of possible evolutionary histories that might not be present in currently available alignment sets. Among the nine programs tested, the iterative approach available in Mafft (L-INS-i) and ProbCons were consistently the most accurate, with Mafft being the faster of the two.


Asunto(s)
Secuencia de Aminoácidos , Proteínas/química , Alineación de Secuencia/métodos , Programas Informáticos , Biología Computacional , Simulación por Computador , Bases de Datos de Proteínas , Eliminación de Gen , Mutación , Conformación Proteica , Proteínas/genética , Alineación de Secuencia/normas
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