Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 41
Filtrar
1.
BMC Genomics ; 25(1): 251, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38448820

RESUMO

BACKGROUND: The Illumina family of Infinium Methylation BeadChip microarrays has been widely used over the last 15 years for genome-wide DNA methylation profiling, including large-scale and population-based studies, due to their ease of use and cost effectiveness. Succeeding the popular HumanMethylationEPIC BeadChip (EPICv1), the recently released Infinium MethylationEPIC v2.0 BeadChip (EPICv2) claims to extend genomic coverage to more than 935,000 CpG sites. Here, we comprehensively characterise the reproducibility, reliability and annotation of the EPICv2 array, based on bioinformatic analysis of both manifest data and new EPICv2 data from diverse biological samples. RESULTS: We find a high degree of reproducibility with EPICv1, evidenced by comparable sensitivity and precision from empirical cross-platform comparison incorporating whole genome bisulphite sequencing (WGBS), and high correlation between technical sample replicates, including between samples with DNA input levels below the manufacturer's recommendation. We provide a full assessment of probe content, evaluating genomic distribution and changes from previous array versions. We characterise EPICv2's new feature of replicated probes and provide recommendations as to the superior probes. In silico analysis of probe sequences demonstrates that probe cross-hybridisation remains a significant problem in EPICv2. By mapping the off-target sites at single nucleotide resolution and comparing with WGBS we show empirical evidence for preferential off-target binding. CONCLUSIONS: Overall, we find EPICv2 a worthy successor to the previous Infinium methylation microarrays, however some technical issues remain. To support optimal EPICv2 data analysis we provide an expanded version of the EPICv2 manifest to aid researchers in understanding probe design, data processing, choosing appropriate probes for analysis and for integration with methylation datasets from previous versions of the Infinium Methylation BeadChip.


Assuntos
Biologia Computacional , Metilação de DNA , Sulfitos , Reprodutibilidade dos Testes , Análise de Dados
2.
Nat Struct Mol Biol ; 31(3): 498-512, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38182927

RESUMO

Three-dimensional (3D) epigenome remodeling is an important mechanism of gene deregulation in cancer. However, its potential as a target to counteract therapy resistance remains largely unaddressed. Here, we show that epigenetic therapy with decitabine (5-Aza-mC) suppresses tumor growth in xenograft models of pre-clinical metastatic estrogen receptor positive (ER+) breast tumor. Decitabine-induced genome-wide DNA hypomethylation results in large-scale 3D epigenome deregulation, including de-compaction of higher-order chromatin structure and loss of boundary insulation of topologically associated domains. Significant DNA hypomethylation associates with ectopic activation of ER-enhancers, gain in ER binding, creation of new 3D enhancer-promoter interactions and concordant up-regulation of ER-mediated transcription pathways. Importantly, long-term withdrawal of epigenetic therapy partially restores methylation at ER-enhancer elements, resulting in a loss of ectopic 3D enhancer-promoter interactions and associated gene repression. Our study illustrates the potential of epigenetic therapy to target ER+ endocrine-resistant breast cancer by DNA methylation-dependent rewiring of 3D chromatin interactions, which are associated with the suppression of tumor growth.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Decitabina/farmacologia , Decitabina/uso terapêutico , Decitabina/metabolismo , Epigenoma , Metilação de DNA/genética , Cromatina , Epigênese Genética , DNA/metabolismo , Regulação Neoplásica da Expressão Gênica
3.
Am J Hosp Palliat Care ; 41(6): 610-618, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37553275

RESUMO

Background: Early and integrated palliative care is recommended for patients with idiopathic pulmonary fibrosis. Unfortunately, palliative care delivery remains poor due to various barriers in practice. This study describes various palliative care delivery models in a real-world cohort of patients with idiopathic pulmonary fibrosis, examines the predictors of survival in this cohort of patients, and explores the impact of palliative care on survival. Design: Charts were reviewed retrospectively and analyzed. The primary outcome was survival during a 4-year follow-up period. Two multivariable models were created to examine the impact of therapeutic strategies including palliative intervention on survival. Results: 298 patients with idiopathic pulmonary fibrosis were enrolled from 3 interstitial lung disease clinics with different palliative care models in Edmonton, Canada; Bristol, UK; and Kingston, Canada. 200 (67%) patients received palliative care and 119 (40%) died during follow up. Primary palliative care models (Edmonton and Bristol) delivered palliative care to 96% and 100% respectively compared 21% in the referral model (Queens). Palliative care [adjusted hazard ratio (aHR) .28 (.12-.65)] along with the use of antifibrotics [aHR .56 (.37-.84)], and body mass index >30 [aHR .47 (.37-.85)] reduced the risk of death in our idiopathic pulmonary fibrosis cohort. Opioid use was associated with worse survival [aHR 2.11 (1.30-23.43)]. Conclusions: Both palliative care and antifibrotic use were associated with survival benefit in this cohort of patients with idiopathic pulmonary fibrosis after adjusting for covariates. The benefit was seen despite differences in disease severity and different palliative care delivery models.

4.
J Clin Nurs ; 30(5-6): 757-764, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33348470

RESUMO

AIMS: This study aimed to investigate the experiences and challenges of New Zealand registered nurses of Chinese ethnicity who have been working during the COVID-19 pandemic. BACKGROUND: New Zealand's nursing workforce is becoming increasingly multicultural as foreign nurses make up an essential part of the New Zealand health workforce. The ongoing COVID-19 pandemic has highlighted the contributions that nurses have made in providing front-line services to the public. However, little has been documented about challenges and experiences of this minority ethnic group-Chinese nurses-who have been working as registered nurses in New Zealand during the COVID-19 pandemic. METHODS: This study used an anonymous online questionnaire and a thematic approach to establishing understandings of the experiences of New Zealand registered nurses of Chinese ethnicity in working through the COVID-19 pandemic. A total of 51 Chinese nurses completed this survey. A self-explanatory checklist for reporting results of Internet e-surveys (CHERRIES) was used for the purpose of the quality of this online survey. RESULTS: The result showed that 47.06% participants (n = 24) reported negative experiences including racial discrimination, workplace bullying and judgement, while 52.94% (n = 27) participants reported positive working experiences including supports received in the workplace and positive recognition by the pubic in New Zealand. CONCLUSION: Ethnic minority nurses are key assets to the New Zealand health system. It is important to understand their experiences and challenges, particularly during the COVID-19 pandemic to make sure they are supported and protected from any physical and emotional injury. RELEVANCE TO CLINICAL PRACTICE: COVID-19 has brought additional challenges and concerns to nurses who are working on the front line of health services. Having knowledge of nurses' working experiences will help with their job satisfaction and has potential implications for the sustainability of the New Zealand nursing workforce and retention strategies to address nursing workforce shortages which is foreseeable in New Zealand.


Assuntos
Povo Asiático , COVID-19 , Grupos Minoritários , Enfermeiras e Enfermeiros , Povo Asiático/psicologia , Povo Asiático/estatística & dados numéricos , COVID-19/enfermagem , China/etnologia , Humanos , Grupos Minoritários/psicologia , Grupos Minoritários/estatística & dados numéricos , Nova Zelândia/epidemiologia , Enfermeiras e Enfermeiros/psicologia , Enfermeiras e Enfermeiros/estatística & dados numéricos
5.
Clin Epigenetics ; 12(1): 90, 2020 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-32571390

RESUMO

BACKGROUND: DNA methylation is a well-studied epigenetic mark that is frequently altered in diseases such as cancer, where specific changes are known to reflect the type and severity of the disease. Therefore, there is a growing interest in assessing the clinical utility of DNA methylation as a biomarker for diagnosing disease and guiding treatment. The development of an accurate loci-specific methylation assay, suitable for use on low-input clinical material, is crucial for advancing DNA methylation biomarkers into a clinical setting. A targeted multiplex bisulphite PCR sequencing approach meets these needs by allowing multiple DNA methylated regions to be interrogated simultaneously in one experiment on limited clinical material. RESULTS: Here, we provide an updated protocol and recommendations for multiplex bisulphite PCR sequencing (MBPS) assays for target DNA methylation analysis. We describe additional steps to improve performance and reliability: (1) pre-sequencing PCR optimisation which includes assessing the optimal PCR cycling temperature and primer concentration and (2) post-sequencing PCR optimisation to achieve uniform coverage of each amplicon. We use a gradient of methylated controls to demonstrate how PCR bias can be assessed and corrected. Methylated controls also allow assessment of the sensitivity of methylation detection for each amplicon. Here, we show that the MBPS assay can amplify as little as 0.625 ng starting DNA and can detect methylation differences of 1% with a sequencing coverage of 1000 reads. Furthermore, the multiplex bisulphite PCR assay can comprehensively interrogate multiple regions on 1-5 ng of formalin-fixed paraffin-embedded DNA or circulating cell-free DNA. CONCLUSIONS: The MBPS assay is a valuable approach for assessing methylated DNA regions in clinical samples with limited material. The optimisation and additional quality control steps described here improve the performance and reliability of this method, advancing it towards potential clinical applications in biomarker studies.


Assuntos
Metilação de DNA , Reação em Cadeia da Polimerase Multiplex/métodos , Neoplasias da Próstata/diagnóstico , Sequenciamento Completo do Genoma/métodos , Linhagem Celular Tumoral , Ilhas de CpG , Detecção Precoce de Câncer , Epigênese Genética , Marcadores Genéticos , Humanos , Masculino , Neoplasias da Próstata/genética , Tamanho da Amostra , Sensibilidade e Especificidade
6.
Ann Am Thorac Soc ; 17(6): 706-713, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32197048

RESUMO

Rationale: Even though idiopathic pulmonary fibrosis (IPF) is a disease with high morbidity and mortality and no cure, palliative care is rarely implemented, leading to high symptom burden and unmet care needs. In 2012, we implemented a multidisciplinary collaborative (MDC) care model linking clinic and community multidisciplinary teams to provide an early integrated palliative approach, focusing on early symptom management and advance care planning.Objectives: To evaluate the differences in resource use and associated costs of end-of-life care between patients with IPF who received early integrated palliative care and patients with IPF who received conventional treatment.Methods: Using administrative health data, we identified all patients in the Province of Alberta, Canada, who presented to a hospital with an IPF diagnosis between January 1, 2012, and December 31, 2018, and died within this time frame. We compared three groups of patients: those who received MDC care (our clinic patients), specialist care (SC; respirologist), or non-specialist care (NSC; no contact with a respiratory clinic). The primary outcomes were healthcare resource use and costs in the year before death.Results: Of 2,768 patients across the three study groups, in the last year of life, MDC patients were more than three times as likely as SC patients to have received antifibrotic therapies (odds ratio [OR], 3.0; 95% confidence interval [CI], 1.8-5.2), almost twice as likely to have received pulmonary rehabilitation (OR, 1.9; 95% CI, 1.1-3.4), and 36% more likely to have received opiates (OR, 1.4; 95% CI, 0.8-2.3). The median total healthcare costs in the last 3 months of life were approximately C$7,700 lower for MDC patients than for those receiving SC, driven primarily by fewer hospitalizations and emergency department visits. MDC patients were also less likely to die in the hospital (44.9% MDC vs. 64.9% SC vs. 66.8% NSC; P < 0.001) and had the highest rates of no hospitalization in the last year of life.Conclusions: An integrated palliative approach in IPF is associated with improvements in the quality of end-of-life care and reduction in costs. Transformation of care models is required to deliver palliative care for patients with IPF. MDC teams within such models can address the high burden of unmet needs for symptom management, advance care planning, and community support in this complex population.


Assuntos
Prestação Integrada de Cuidados de Saúde , Custos de Cuidados de Saúde , Fibrose Pulmonar Idiopática/terapia , Cuidados Paliativos/métodos , Planejamento Antecipado de Cuidados , Idoso , Idoso de 80 Anos ou mais , Alberta , Feminino , Mortalidade Hospitalar , Humanos , Fibrose Pulmonar Idiopática/economia , Masculino , Cuidados Paliativos/economia , Assistência Terminal/normas
7.
Sci Rep ; 9(1): 9511, 2019 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-31266983

RESUMO

Adipocytes support key metabolic and endocrine functions of adipose tissue. Lipid is stored in two major classes of depots, namely visceral adipose (VA) and subcutaneous adipose (SA) depots. Increased visceral adiposity is associated with adverse health outcomes, whereas the impact of SA tissue is relatively metabolically benign. The precise molecular features associated with the functional differences between the adipose depots are still not well understood. Here, we characterised transcriptomes and methylomes of isolated adipocytes from matched SA and VA tissues of individuals with normal BMI to identify epigenetic differences and their contribution to cell type and depot-specific function. We found that DNA methylomes were notably distinct between different adipocyte depots and were associated with differential gene expression within pathways fundamental to adipocyte function. Most striking differential methylation was found at transcription factor and developmental genes. Our findings highlight the importance of developmental origins in the function of different fat depots.


Assuntos
Metilação de DNA , Epigênese Genética , Gordura Intra-Abdominal/metabolismo , Gordura Subcutânea/metabolismo , Transcriptoma , Adipócitos/citologia , Adipócitos/metabolismo , Adulto , Sítios de Ligação , Índice de Massa Corporal , Regulação para Baixo , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Humanos , Gordura Intra-Abdominal/citologia , Pessoa de Meia-Idade , Elementos Reguladores de Transcrição , Gordura Subcutânea/citologia , Fatores de Transcrição/metabolismo , Regulação para Cima
8.
J Contin Educ Nurs ; 50(4): 183-188, 2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-30942893

RESUMO

BACKGROUND: This study examines the appropriateness of using learner-centered teaching approaches with international nurses in New Zealand. A 12-week international nurse training program was designed by a large tertiary institution in New Zealand in response to the request of Shenzhen local hospital officials in China. Three groups of 30 Chinese nurses attended this program. METHOD: Responses from program participants were garnered through an online survey and a focus group interview. All qualitative data were analyzed using a thematic approach. RESULTS: The study results highlighted that a positive aspect of the program was the collaborative decision making invited by the program coordinator about the learning goals, topics, and content. Participants reported how the shift in power from a teacher-directed program to a learner-centric approach helped them to engage more fully in the program and achieve greater, more successful individual outcomes. CONCLUSION: This project demonstrated the feasibility of implementing an international nursing training program using a culturally appropriate learner-centric teaching approach. The findings suggest that a learner-centric teaching style effectively addresses the diverse professional needs and cultural backgrounds of international nursing practitioners. [J Contin Educ Nurs. 2019;50(4):183-188.].


Assuntos
Educação Continuada em Enfermagem/organização & administração , Enfermeiros Internacionais/educação , Adulto , China , Currículo , Tomada de Decisões , Avaliação Educacional , Estudos de Viabilidade , Feminino , Objetivos , Humanos , Masculino
9.
Epigenetics Chromatin ; 12(1): 12, 2019 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-30755246

RESUMO

BACKGROUND: ATP-dependent chromatin remodelling complexes are responsible for establishing and maintaining the positions of nucleosomes. Chromatin remodellers are targeted to chromatin by transcription factors and non-coding RNA to remodel the chromatin into functional states. However, the influence of chromatin remodelling on shaping the functional epigenome is not well understood. Moreover, chromatin remodellers have not been extensively explored as a collective group across two-dimensional and three-dimensional epigenomic layers. RESULTS: Here, we have integrated the genome-wide binding profiles of eight chromatin remodellers together with DNA methylation, nucleosome positioning, histone modification and Hi-C chromosomal contacts to reveal that chromatin remodellers can be stratified into two functional groups. Group 1 (BRG1, SNF2H, CHD3 and CHD4) has a clear preference for binding at 'actively marked' chromatin and Group 2 (BRM, INO80, SNF2L and CHD1) for 'repressively marked' chromatin. We find that histone modifications and chromatin architectural features, but not DNA methylation, stratify the remodellers into these functional groups. CONCLUSIONS: Our findings suggest that chromatin remodelling events are synchronous and that chromatin remodellers themselves should be considered simultaneously and not as individual entities in isolation or necessarily by structural similarity, as they are traditionally classified. Their coordinated function should be considered by preference for chromatin features in order to gain a more accurate and comprehensive picture of chromatin regulation.


Assuntos
Montagem e Desmontagem da Cromatina , Epigênese Genética , Código das Histonas , ATPases Associadas a Diversas Atividades Celulares , Adenosina Trifosfatases/metabolismo , Proteínas Cromossômicas não Histona/metabolismo , DNA Helicases/metabolismo , Proteínas de Ligação a DNA/metabolismo , Genoma Humano , Humanos , Complexo Mi-2 de Remodelação de Nucleossomo e Desacetilase/metabolismo , Proteínas Nucleares/metabolismo , Fatores de Transcrição/metabolismo
10.
Cancer Cell ; 35(2): 297-314.e8, 2019 02 11.
Artigo em Inglês | MEDLINE | ID: mdl-30753827

RESUMO

Promoter CpG islands are typically unmethylated in normal cells, but in cancer a proportion are subject to hypermethylation. Using methylome sequencing we identified CpG islands that display partial methylation encroachment across the 5' or 3' CpG island borders. CpG island methylation encroachment is widespread in prostate and breast cancer and commonly associates with gene suppression. We show that the pattern of H3K4me1 at CpG island borders in normal cells predicts the different modes of cancer CpG island hypermethylation. Notably, genetic manipulation of Kmt2d results in concordant alterations in H3K4me1 levels and CpG island border DNA methylation encroachment. Our findings suggest a role for H3K4me1 in the demarcation of CpG island methylation borders in normal cells, which become eroded in cancer.


Assuntos
Ilhas de CpG , Metilação de DNA , DNA de Neoplasias/metabolismo , Histonas/metabolismo , Neoplasias/metabolismo , 5-Metilcitosina/análogos & derivados , 5-Metilcitosina/metabolismo , Animais , Linhagem Celular Tumoral , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica , Histona-Lisina N-Metiltransferase/genética , Histona-Lisina N-Metiltransferase/metabolismo , Histonas/genética , Humanos , Masculino , Metilação , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteína de Leucina Linfoide-Mieloide/genética , Proteína de Leucina Linfoide-Mieloide/metabolismo , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Neoplasias/genética , Regiões Promotoras Genéticas
11.
Nat Commun ; 10(1): 416, 2019 01 24.
Artigo em Inglês | MEDLINE | ID: mdl-30679435

RESUMO

DNA replication timing is known to facilitate the establishment of the epigenome, however, the intimate connection between replication timing and changes to the genome and epigenome in cancer remain largely uncharacterised. Here, we perform Repli-Seq and integrated epigenome analyses and demonstrate that genomic regions that undergo long-range epigenetic deregulation in prostate cancer also show concordant differences in replication timing. A subset of altered replication timing domains are conserved across cancers from different tissue origins. Notably, late-replicating regions in cancer cells display a loss of DNA methylation, and a switch in heterochromatin features from H3K9me3-marked constitutive to H3K27me3-marked facultative heterochromatin. Finally, analysis of 214 prostate and 35 breast cancer genomes reveal that late-replicating regions are prone to cis and early-replication to trans chromosomal rearrangements. Together, our data suggests that the nature of chromosomal rearrangement in cancer is related to the spatial and temporal positioning and altered epigenetic states of early-replicating compared to late-replicating loci.


Assuntos
Aberrações Cromossômicas , Período de Replicação do DNA/fisiologia , Epigênese Genética/fisiologia , Neoplasias/genética , Neoplasias da Mama , Linhagem Celular Tumoral , Metilação de DNA , Replicação do DNA , Desoxirribonuclease I/análise , Epigenômica , Feminino , Regulação Neoplásica da Expressão Gênica , Genoma , Genômica , Heterocromatina , Humanos , Masculino , Neoplasias da Próstata , Sequenciamento Completo do Genoma
12.
Bioinformatics ; 35(4): 560-570, 2019 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-30084929

RESUMO

MOTIVATION: A synoptic view of the human genome benefits chiefly from the application of nucleic acid sequencing and microarray technologies. These platforms allow interrogation of patterns such as gene expression and DNA methylation at the vast majority of canonical loci, allowing granular insights and opportunities for validation of original findings. However, problems arise when validating against a "gold standard" measurement, since this immediately biases all subsequent measurements towards that particular technology or protocol. Since all genomic measurements are estimates, in the absence of a "gold standard" we instead empirically assess the measurement precision and sensitivity of a large suite of genomic technologies via a consensus modelling method called the row-linear model. This method is an application of the American Society for Testing and Materials Standard E691 for assessing interlaboratory precision and sources of variability across multiple testing sites. Both cross-platform and cross-locus comparisons can be made across all common loci, allowing identification of technology- and locus-specific tendencies. RESULTS: We assess technologies including the Infinium MethylationEPIC BeadChip, whole genome bisulfite sequencing (WGBS), two different RNA-Seq protocols (PolyA+ and Ribo-Zero) and five different gene expression array platforms. Each technology thus is characterised herein, relative to the consensus. We showcase a number of applications of the row-linear model, including correlation with known interfering traits. We demonstrate a clear effect of cross-hybridisation on the sensitivity of Infinium methylation arrays. Additionally, we perform a true interlaboratory test on a set of samples interrogated on the same platform across twenty-one separate testing laboratories. AVAILABILITY AND IMPLEMENTATION: A full implementation of the row-linear model, plus extra functions for visualisation, are found in the R package consensus at https://github.com/timpeters82/consensus. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Assuntos
Biologia Computacional , Metilação de DNA , Genômica , Genoma Humano , Humanos , Análise de Sequência com Séries de Oligonucleotídeos , Software
13.
Genome Res ; 28(5): 625-638, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29650553

RESUMO

The growth and progression of solid tumors involves dynamic cross-talk between cancer epithelium and the surrounding microenvironment. To date, molecular profiling has largely been restricted to the epithelial component of tumors; therefore, features underpinning the persistent protumorigenic phenotype of the tumor microenvironment are unknown. Using whole-genome bisulfite sequencing, we show for the first time that cancer-associated fibroblasts (CAFs) from localized prostate cancer display remarkably distinct and enduring genome-wide changes in DNA methylation, significantly at enhancers and promoters, compared to nonmalignant prostate fibroblasts (NPFs). Differentially methylated regions associated with changes in gene expression have cancer-related functions and accurately distinguish CAFs from NPFs. Remarkably, a subset of changes is shared with prostate cancer epithelial cells, revealing the new concept of tumor-specific epigenome modifications in the tumor and its microenvironment. The distinct methylome of CAFs provides a novel epigenetic hallmark of the cancer microenvironment and promises new biomarkers to improve interpretation of diagnostic samples.


Assuntos
Metilação de DNA , Epigenômica/métodos , Neoplasias da Próstata/genética , Microambiente Tumoral/genética , Fibroblastos Associados a Câncer/metabolismo , Células Cultivadas , Fibroblastos/metabolismo , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Genoma Humano/genética , Humanos , Masculino , Regiões Promotoras Genéticas/genética , Neoplasias da Próstata/patologia , Sequenciamento Completo do Genoma/métodos
14.
Methods Mol Biol ; 1708: 285-302, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29224150

RESUMO

Epigenetic regulation plays a critical role in gene expression, cellular differentiation, and disease. There is a complex interplay between the different layers of epigenetic information, including DNA methylation, nucleosome positions, histone modifications, histone variants, and other important epigenetic regulators. The different modifications do not act independently of each other and their relationship plays an important role in governing the regulation of the epigenome. Of these, DNA methylation is the best-studied epigenetic modification in mammals. However, the direct relationship between DNA methylation and chromatin modifications has been difficult to unravel with existing technologies, with epigenome-wide integration studies still based on "overlaying" independent chromatin modification and DNA methylation maps. Bisulphite sequencing enables the methylation state of every cytosine residue to be analyzed across a given molecule in a strand-specific context. Here, we describe a direct approach to interrogating the DNA methylation status of specific chromatin-marked DNA, using high-throughput sequencing of bisulphite-treated chromatin immunoprecipitated DNA (BisChIP-seq). This combined approach enables the exquisite relationship between chromatin-modified DNA or transcription factor-associated DNA and the methylation state of each targeted allele to be directly interrogated. BisChIP-Seq can now be widely applied genome-wide to further understand the molecular relationship between DNA methylation and other important epigenetic regulators.


Assuntos
Imunoprecipitação da Cromatina/métodos , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Análise de Sequência de DNA/métodos , Alelos , Animais , Linhagem Celular , Metilação de DNA , Epigênese Genética , Humanos , Mamíferos/genética , Sulfitos
15.
Nat Commun ; 8(1): 1346, 2017 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-29116202

RESUMO

Acetylation of the histone variant H2A.Z (H2A.Zac) occurs at active promoters and is associated with oncogene activation in prostate cancer, but its role in enhancer function is still poorly understood. Here we show that H2A.Zac containing nucleosomes are commonly redistributed to neo-enhancers in cancer resulting in a concomitant gain of chromatin accessibility and ectopic gene expression. Notably incorporation of acetylated H2A.Z nucleosomes is a pre-requisite for activation of Androgen receptor (AR) associated enhancers. H2A.Zac nucleosome occupancy is rapidly remodeled to flank the AR sites to initiate the formation of nucleosome-free regions and the production of AR-enhancer RNAs upon androgen treatment. Remarkably higher levels of global H2A.Zac correlate with poorer prognosis. Altogether these data demonstrate the novel contribution of H2A.Zac in activation of newly formed enhancers in prostate cancer.


Assuntos
Elementos Facilitadores Genéticos/genética , Histonas/metabolismo , Neoplasias da Próstata/genética , Acetilação , Cromatina/genética , Cromatina/metabolismo , Intervalo Livre de Doença , Epigênese Genética , Regulação Neoplásica da Expressão Gênica , Histonas/genética , Humanos , Masculino , Nucleossomos/genética , Nucleossomos/metabolismo , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/mortalidade , Receptores Androgênicos/genética , Receptores Androgênicos/metabolismo
16.
Oncotarget ; 8(44): 76279-76289, 2017 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-29100311

RESUMO

HADH is a key enzyme in fatty acid oxidation. The aim of this study was to identify the role of HADH in gastric cancer. We analyzed the expression of HADH in 102 pairs of gastric cancer samples. Western blot analysis revealed that HADH was decreased in stage I/II gastric cancer samples compared to matched adjacent normal gastric tissue, and its expression was further decreased in stage III/IV samples. Importantly, the reduced expression of HADH was associated with increased expression of p-Akt and reduced expression of PTEN in the gastric carcinoma tumor samples. To determine the significance of HADH downregulation in gastric cancer progression, we tested the impact of HADH knockdown or overexpression on the migration and invasion of the gastric cancer cells using a transwell assay. Knockdown of HADH significantly promoted gastric cancer cell migration and invasion, which was associated with increased expression of p-Akt. The PI3K inhibitor LY294002 inhibited HADH shRNA induced migration/invasion, and abolished the upregulation of p-Akt. By contrast, HADH overexpression inhibited the migration and invasion of MKN45 cells. Herein, for the first time, we demonstrate that downregulation of HADH promotes gastric cancer progression via activation of Akt signaling pathway.

17.
Artigo em Inglês | MEDLINE | ID: mdl-28588421

RESUMO

BACKGROUND: This open-label study evaluated the safety and efficacy of a novel product for the removal of impacted cerumen in adult patients. METHODS: This was a prospective, single-center, single-arm, self-controlled clinical trial conducted in a community general practice setting. The novel product contains glycolic acid in an otologically-acceptable buffer containing sodium bicarbonate and glycerin and other buffering agents. The product was instilled into the ear canal prior to irrigation with warm water. Severity of cerumen impaction was graded using a 5-point scale. Improvement in tympanic membrane visualization was assessed after instillation and irrigation. RESULTS: A majority (83%, 25/30) of ears showed improvement with one application: with 53% (16/30) totally dissolved and gained 100% TM visualization. Total dissolution was observed in 80% (24/30) of the study ears per the intent-to-treat analysis and 86% (24/28) if irrigation instructions were followed. Most of the ears/participants that had cerumen blockage symptoms experienced significant improvement with the application. Feelings of fullness disappeared in 92% (11/12) of the affected ears; ears itching, 91% (10/11); water trapping or cracking, 78%, and decreased hearing disappeared in 71% (10/14). All (100%, 18) of the participants who completed the application satisfaction assessment were satisfied with the application process in terms of time needed and the overall rinse procedure. Only one mild adverse event (ear pruritis) occurred that was related to application. CONCLUSIONS: The tested cerumen removal product was effective and safe for removing moderate to severe blockage in patients with impacted cerumen. Procedure satisfaction for the product was high. TRIAL REGISTRATION: This trial is registered on http://www.clinicaltrials.gov/. The registration number is NCT02829294. The trial was retrospectively registered on July 8, 2016.

18.
EBioMedicine ; 16: 238-250, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28161398

RESUMO

While angiotensin II (ang II) has been implicated in the pathogenesis of cardiac cachexia (CC), the molecules that mediate ang II's wasting effect have not been identified. It is known TNF-α level is increased in patients with CC, and TNF-α release is triggered by ang II. We therefore hypothesized that ang II induced muscle wasting is mediated by TNF-α. Ang II infusion led to skeletal muscle wasting in wild type (WT) but not in TNF alpha type 1 receptor knockout (TNFR1KO) mice, suggesting that ang II induced muscle loss is mediated by TNF-α through its type 1 receptor. Microarray analysis identified cholesterol 25-hydroxylase (Ch25h) as the down stream target of TNF-α. Intraperitoneal injection of 25-hydroxycholesterol (25-OHC), the product of Ch25h, resulted in muscle loss in C57BL/6 mice, accompanied by increased expression of atrogin-1, MuRF1 and suppression of IGF-1/Akt signaling pathway. The identification of 25-OHC as an inducer of muscle wasting has implications for the development of specific treatment strategies in preventing muscle loss.


Assuntos
Glicogênio Sintase Quinase 3 beta/metabolismo , Músculo Esquelético/metabolismo , Atrofia Muscular/metabolismo , Transdução de Sinais , Angiotensina II , Animais , Western Blotting , Linhagem Celular , Células Cultivadas , Perfilação da Expressão Gênica/métodos , Glicogênio Sintase Quinase 3 beta/antagonistas & inibidores , Hidroxicolesteróis , Fator de Crescimento Insulin-Like I/genética , Fator de Crescimento Insulin-Like I/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas Musculares/genética , Proteínas Musculares/metabolismo , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/patologia , Atrofia Muscular/induzido quimicamente , Atrofia Muscular/prevenção & controle , Mioblastos/citologia , Mioblastos/metabolismo , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptores Tipo I de Fatores de Necrose Tumoral/genética , Receptores Tipo I de Fatores de Necrose Tumoral/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Proteínas Ligases SKP Culina F-Box/genética , Proteínas Ligases SKP Culina F-Box/metabolismo , Esteroide Hidroxilases/genética , Esteroide Hidroxilases/metabolismo , Tiadiazóis/farmacologia , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo
19.
Sci Rep ; 6: 38871, 2016 12 12.
Artigo em Inglês | MEDLINE | ID: mdl-27941907

RESUMO

The aim of this study was to identify biomarkers for gastric cancer (GC) by iTRAQ. Using proteins extracted from a panel of 4 pairs of gastric adenocarcinoma samples (stage III-IV, Her-2 negative), we identified 10 up regulated and 9 down regulated proteins in all four pairs of GC samples compared to adjacent normal gastric tissue. The up regulated proteins are mainly involved in cell motility, while the down regulated proteins are mitochondrial enzymes involved in energy metabolism. The expression of three up regulated proteins (ANXA1, NNMT, fibulin-5) and one of the down regulated proteins (UQCRC1) was validated by Western Blot in 97 GC samples. ANXA1 was up regulated in 61.36% of stage I/II GC samples compared to matched adjacent normal gastric tissue, and its expression increased further in stage III/IV samples. Knockdown of ANXA1 by siRNA significantly inhibited GC cell migration and invasion, whereas over expression of ANXA1 promoted migration and invasion. We found decreased expression of UQCRC1 in all stages of GC samples. Our data suggest that increased cell motility and decreased mitochondrial energy metabolism are important hallmarks during the development of GC.


Assuntos
Adenocarcinoma/química , Biomarcadores Tumorais/análise , Proteínas de Neoplasias/análise , Proteômica/métodos , Neoplasias Gástricas/química , Espectrometria de Massas em Tandem/métodos , Idoso , Western Blotting , Movimento Celular/genética , Metabolismo Energético/genética , Feminino , Técnica Direta de Fluorescência para Anticorpo , Regulação Neoplásica da Expressão Gênica , Ontologia Genética , Humanos , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica
20.
Nat Commun ; 6: 5899, 2015 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-25641231

RESUMO

Epigenetic alterations in the cancer methylome are common in breast cancer and provide novel options for tumour stratification. Here, we perform whole-genome methylation capture sequencing on small amounts of DNA isolated from formalin-fixed, paraffin-embedded tissue from triple-negative breast cancer (TNBC) and matched normal samples. We identify differentially methylated regions (DMRs) enriched with promoters associated with transcription factor binding sites and DNA hypersensitive sites. Importantly, we stratify TNBCs into three distinct methylation clusters associated with better or worse prognosis and identify 17 DMRs that show a strong association with overall survival, including DMRs located in the Wilms tumour 1 (WT1) gene, bi-directional-promoter and antisense WT1-AS. Our data reveal that coordinated hypermethylation can occur in oestrogen receptor-negative disease, and that characterizing the epigenetic framework provides a potential signature to stratify TNBCs. Together, our findings demonstrate the feasibility of profiling the cancer methylome with limited archival tissue to identify regulatory regions associated with cancer.


Assuntos
Metilação de DNA/fisiologia , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/patologia , Metilação de DNA/genética , Epigenômica , Feminino , Humanos , Dados de Sequência Molecular , Prognóstico
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...