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1.
J Neurooncol ; 145(3): 595, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31768714

RESUMO

In the original article, the author names were published incorrectly. The names are correct in this publication.

2.
Nat Genet ; 39(8): 989-94, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17618283

RESUMO

Using a multistage genetic association approach comprising 7,480 affected individuals and 7,779 controls, we identified markers in chromosomal region 8q24 associated with colorectal cancer. In stage 1, we genotyped 99,632 SNPs in 1,257 affected individuals and 1,336 controls from Ontario. In stages 2-4, we performed serial replication studies using 4,024 affected individuals and 4,042 controls from Seattle, Newfoundland and Scotland. We identified one locus on chromosome 8q24 and another on 9p24 having combined odds ratios (OR) for stages 1-4 of 1.18 (trend; P = 1.41 x 10(-8)) and 1.14 (trend; P = 1.32 x 10(-5)), respectively. Additional analyses in 2,199 affected individuals and 2,401 controls from France and Europe supported the association at the 8q24 locus (OR = 1.16, trend; 95% confidence interval (c.i.): 1.07-1.26; P = 5.05 x 10(-4)). A summary across all seven studies at the 8q24 locus was highly significant (OR = 1.17, c.i.: 1.12-1.23; P = 3.16 x 10(-11)). This locus has also been implicated in prostate cancer.


Assuntos
Cromossomos Humanos Par 8 , Neoplasias Colorretais/genética , Predisposição Genética para Doença , Polimorfismo de Nucleotídeo Único , Estudos de Casos e Controles , Mapeamento Cromossômico , Humanos , Desequilíbrio de Ligação , Pessoa de Meia-Idade
3.
BMC Bioinformatics ; 13: 206, 2012 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-22901030

RESUMO

BACKGROUND: It is now well established that nearly 20% of human cancers are caused by infectious agents, and the list of human oncogenic pathogens will grow in the future for a variety of cancer types. Whole tumor transcriptome and genome sequencing by next-generation sequencing technologies presents an unparalleled opportunity for pathogen detection and discovery in human tissues but requires development of new genome-wide bioinformatics tools. RESULTS: Here we present CaPSID (Computational Pathogen Sequence IDentification), a comprehensive bioinformatics platform for identifying, querying and visualizing both exogenous and endogenous pathogen nucleotide sequences in tumor genomes and transcriptomes. CaPSID includes a scalable, high performance database for data storage and a web application that integrates the genome browser JBrowse. CaPSID also provides useful metrics for sequence analysis of pre-aligned BAM files, such as gene and genome coverage, and is optimized to run efficiently on multiprocessor computers with low memory usage. CONCLUSIONS: To demonstrate the usefulness and efficiency of CaPSID, we carried out a comprehensive analysis of both a simulated dataset and transcriptome samples from ovarian cancer. CaPSID correctly identified all of the human and pathogen sequences in the simulated dataset, while in the ovarian dataset CaPSID's predictions were successfully validated in vitro.


Assuntos
Biologia Computacional/métodos , Bases de Dados Genéticas , Genoma Humano , Software , Transcriptoma , Algoritmos , Linhagem Celular Tumoral , Simulação por Computador , Feminino , Humanos , Internet , Vírus Oncogênicos/genética , Neoplasias Ovarianas/genética , Sensibilidade e Especificidade
4.
Cancers (Basel) ; 13(16)2021 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-34439288

RESUMO

Lung adenocarcinoma (LUAD) is the most common type of lung cancer and a leading cause of cancer-related deaths worldwide. Despite important recent advances, the prognosis for LUAD patients is still unfavourable, with a 5 year-survival rate close to 15%. Improving the characterization of lung tumors is important to develop alternative options for the diagnosis and the treatment of this disease. Zinc-finger protein 768 (ZNF768) is a transcription factor that was recently shown to promote proliferation and repress senescence downstream of growth factor signaling. Although ZNF768 protein levels were found to be elevated in LUAD compared to normal lung tissue, it is currently unknown whether ZNF768 expression associates with clinicopathological features in LUAD. Here, using tissue microarrays of clinical LUAD surgical specimens collected from 364 patients, we observed that high levels of ZNF768 is a common characteristic of LUAD. We show that ZNF768 protein levels correlate with high proliferative features in LUAD, including the mitotic score and Ki-67 expression. Supporting a role for ZNF768 in promoting proliferation, we report that ZNF768 depletion severely impairs proliferation in several lung cancer cell lines in vitro. A marked decrease in the expression of key proliferative genes was observed in cancer cell lines depleted from ZNF768. Altogether, our findings support a role for ZNF768 in promoting proliferation of LUAD.

5.
Hum Pathol ; 106: 74-81, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33007357

RESUMO

Lung carcinoid tumors are classified as either typical or atypical based on the presence of necrosis and the maximum mitotic count per 2 mm2 area. Determining the mitotic count, which is manually conducted on slides stained with hematoxylin and eosin (HE), is time-consuming and subject to high interobserver variability. The objective of this study was to test the sensitivity and specificity of a surrogate mitosis marker, phospho-histone-H3 (PHH3) immunostaining, in the processing of pulmonary carcinoids as compared with the standard HE evaluation. Carcinoid tissue blocks that were available from lung resection specimens were analyzed using HE and PHH3 stains. Two thoracic pathologists and two residents determined the mitotic count on HE and PHH3 stains in accordance with the 2015 WHO guidelines and recorded the time required to complete this task. For both methods, the interobserver agreement among raters for the mitotic count/2 mm2 was assessed by conducting intraclass correlation analyses. We found that for both pathologists and residents, the time required to determine the mitotic count using the PHH3 method was reduced compared with the traditional HE method. Furthermore, residents detected more mitoses/2 mm2 using the PHH3 stain compared with the HE method. More importantly, the PHH3 method yielded better interobserver agreement than the HE method in terms of mitoses/mm2 detection. Overall, our data confirmed that histologic assessments of carcinoid tumors using PHH3 staining provides practical benefits in terms of scoring times, mitosis detection, and reproducibility of mitotic counts. In addition, we found that the benefit was even greater for less experienced pathologists.


Assuntos
Biomarcadores Tumorais/análise , Tumor Carcinoide/química , Histonas/análise , Imuno-Histoquímica , Neoplasias Pulmonares/química , Mitose , Adulto , Idoso , Tumor Carcinoide/patologia , Tumor Carcinoide/cirurgia , Feminino , Humanos , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/cirurgia , Masculino , Pessoa de Meia-Idade , Índice Mitótico , Variações Dependentes do Observador , Fosforilação , Valor Preditivo dos Testes , Reprodutibilidade dos Testes
6.
PLoS Genet ; 2(3): e27, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16532062

RESUMO

The Haplotype Map (HapMap) project recently generated genotype data for more than 1 million single-nucleotide polymorphisms (SNPs) in four population samples. The main application of the data is in the selection of tag single-nucleotide polymorphisms (tSNPs) to use in association studies. The usefulness of this selection process needs to be verified in populations outside those used for the HapMap project. In addition, it is not known how well the data represent the general population, as only 90-120 chromosomes were used for each population and since the genotyped SNPs were selected so as to have high frequencies. In this study, we analyzed more than 1,000 individuals from Estonia. The population of this northern European country has been influenced by many different waves of migrations from Europe and Russia. We genotyped 1,536 randomly selected SNPs from two 500-kbp ENCODE regions on Chromosome 2. We observed that the tSNPs selected from the CEPH (Centre d'Etude du Polymorphisme Humain) from Utah (CEU) HapMap samples (derived from US residents with northern and western European ancestry) captured most of the variation in the Estonia sample. (Between 90% and 95% of the SNPs with a minor allele frequency of more than 5% have an r2 of at least 0.8 with one of the CEU tSNPs.) Using the reverse approach, tags selected from the Estonia sample could almost equally well describe the CEU sample. Finally, we observed that the sample size, the allelic frequency, and the SNP density in the dataset used to select the tags each have important effects on the tagging performance. Overall, our study supports the use of HapMap data in other Caucasian populations, but the SNP density and the bias towards high-frequency SNPs have to be taken into account when designing association studies.


Assuntos
Mapeamento Cromossômico , Polimorfismo de Nucleotídeo Único , Alelos , Biologia Computacional , Bases de Dados Genéticas , Estônia , Frequência do Gene , Técnicas Genéticas , Genótipo , Haplótipos , Humanos , Desequilíbrio de Ligação , População Branca
7.
Cardiovasc Pathol ; 43: 107141, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31442825

RESUMO

Coronary angiography is the standard imaging method for determining the site, extent, and severity of coronary artery disease. Several publications have reported discordance between the degree of coronary artery stenosis determined from post-mortem histologic evaluation and coronary angiography. While the 2-dimensional limitations of coronary angiography are well established, the determination of coronary stenosis based on histologic evaluation of passively fixed samples is also associated with significant biases. In this study, we used patients with chronic coronary artery disease to compare the stenosis severity estimates that were determined using the passive fixation method with those determined using the active fixation method. Our results showed a significant discrepancy between the stenosis in passively fixed coronary arteries when compared with coronary angiography in all major coronary vessels combined (P=.002), and in Cx (P=.045) and CD (P=.026). However, there was no mean difference when compared with perfused (actively fixed) samples when all vessels were combined or examined individually. Iso-physiologic mechanical perfusion (active) fixation yielded significantly reduced coronary artery stenosis means when compared to the passive fixation method in post-mortem evaluations during autopsies. This was evident when all vessels were combined (P=.0001) and assessed individually (Cx (P=.003), LAD (P=.025), LM (P=.056) and RC (P=.007)). Autopsies including cardiac explant patients also showed differences in estimates for all vessels combined (P=.0001) and in Cx (P=.016) and RC (P=.006). In summary, our quantitative histopathology analyses using perfused coronary artery stenosis at physiologic pressure showed significant discrepancies when compared with passive histopathology.


Assuntos
Pressão Arterial , Estenose Coronária/patologia , Vasos Coronários/patologia , Fixação de Tecidos/métodos , Idoso , Autopsia , Causas de Morte , Angiografia Coronária , Estenose Coronária/diagnóstico por imagem , Estenose Coronária/mortalidade , Estenose Coronária/fisiopatologia , Vasos Coronários/diagnóstico por imagem , Vasos Coronários/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Índice de Gravidade de Doença , Coloração e Rotulagem
8.
Int J Epidemiol ; 43(6): 1929-44, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25261970

RESUMO

BACKGROUND: Research in modern biomedicine and social science requires sample sizes so large that they can often only be achieved through a pooled co-analysis of data from several studies. But the pooling of information from individuals in a central database that may be queried by researchers raises important ethico-legal questions and can be controversial. In the UK this has been highlighted by recent debate and controversy relating to the UK's proposed 'care.data' initiative, and these issues reflect important societal and professional concerns about privacy, confidentiality and intellectual property. DataSHIELD provides a novel technological solution that can circumvent some of the most basic challenges in facilitating the access of researchers and other healthcare professionals to individual-level data. METHODS: Commands are sent from a central analysis computer (AC) to several data computers (DCs) storing the data to be co-analysed. The data sets are analysed simultaneously but in parallel. The separate parallelized analyses are linked by non-disclosive summary statistics and commands transmitted back and forth between the DCs and the AC. This paper describes the technical implementation of DataSHIELD using a modified R statistical environment linked to an Opal database deployed behind the computer firewall of each DC. Analysis is controlled through a standard R environment at the AC. RESULTS: Based on this Opal/R implementation, DataSHIELD is currently used by the Healthy Obese Project and the Environmental Core Project (BioSHaRE-EU) for the federated analysis of 10 data sets across eight European countries, and this illustrates the opportunities and challenges presented by the DataSHIELD approach. CONCLUSIONS: DataSHIELD facilitates important research in settings where: (i) a co-analysis of individual-level data from several studies is scientifically necessary but governance restrictions prohibit the release or sharing of some of the required data, and/or render data access unacceptably slow; (ii) a research group (e.g. in a developing nation) is particularly vulnerable to loss of intellectual property-the researchers want to fully share the information held in their data with national and international collaborators, but do not wish to hand over the physical data themselves; and (iii) a data set is to be included in an individual-level co-analysis but the physical size of the data precludes direct transfer to a new site for analysis.


Assuntos
Pesquisa Biomédica , Segurança Computacional , Confidencialidade , Conjuntos de Dados como Assunto , Armazenamento e Recuperação da Informação , Biologia Computacional , Bases de Dados Factuais , Humanos , Reino Unido
10.
Int J Epidemiol ; 39(5): 1372-82, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20630989

RESUMO

BACKGROUND: Contemporary bioscience sometimes demands vast sample sizes and there is often then no choice but to synthesize data across several studies and to undertake an appropriate pooled analysis. This same need is also faced in health-services and socio-economic research. When a pooled analysis is required, analytic efficiency and flexibility are often best served by combining the individual-level data from all sources and analysing them as a single large data set. But ethico-legal constraints, including the wording of consent forms and privacy legislation, often prohibit or discourage the sharing of individual-level data, particularly across national or other jurisdictional boundaries. This leads to a fundamental conflict in competing public goods: individual-level analysis is desirable from a scientific perspective, but is prevented by ethico-legal considerations that are entirely valid. METHODS: Data aggregation through anonymous summary-statistics from harmonized individual-level databases (DataSHIELD), provides a simple approach to analysing pooled data that circumvents this conflict. This is achieved via parallelized analysis and modern distributed computing and, in one key setting, takes advantage of the properties of the updating algorithm for generalized linear models (GLMs). RESULTS: The conceptual use of DataSHIELD is illustrated in two different settings. CONCLUSIONS: As the study of the aetiological architecture of chronic diseases advances to encompass more complex causal pathways-e.g. to include the joint effects of genes, lifestyle and environment-sample size requirements will increase further and the analysis of pooled individual-level data will become ever more important. An aim of this conceptual article is to encourage others to address the challenges and opportunities that DataSHIELD presents, and to explore potential extensions, for example to its use when different data sources hold different data on the same individuals.


Assuntos
Métodos Epidemiológicos , Armazenamento e Recuperação da Informação/métodos , Metanálise como Assunto , Causalidade , Confidencialidade , Ética em Pesquisa , Humanos , Projetos de Pesquisa
11.
Hum Genet ; 122(3-4): 345-53, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17638019

RESUMO

Genomic copy number variation (CNV) is a recently identified form of global genetic variation in the human genome. The Affymetrix GeneChip 100 and 500 K SNP genotyping platforms were used to perform a large-scale population-based study of CNV frequency. We constructed a genomic map of 578 CNV regions, covering approximately 220 Mb (7.3%) of the human genome, identifying 183 previously unknown intervals. Copy number changes were observed to occur infrequently (<1%) in the majority (>93%) of these genomic regions, but encompass hundreds of genes and disease loci. This North American population-based map will be a useful resource for future genetic studies.


Assuntos
DNA/genética , Dosagem de Genes , Variação Genética , Células Germinativas/metabolismo , Idoso , Mapeamento Cromossômico , Feminino , Frequência do Gene , Genética Populacional , Genoma Humano , Humanos , Masculino , Pessoa de Meia-Idade , Análise de Sequência com Séries de Oligonucleotídeos , Ontário , Reação em Cadeia da Polimerase , Polimorfismo de Nucleotídeo Único , Sistema de Registros
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