22951 results for "ega"

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• Epigenome and transcriptome profiling of chronic lymphocytic leukemia patients

  Chronic lymphocytic leukemia (CLL) is characterized by substantial clinical heterogeneity, despite relatively few genetic alterations. To provide a basis for studying epigenome deregulation in CLL, we established genome-wide chromatin accessibility maps for 88 CLL samples from 55 patients using the ATAC-seq assay, and we also performed ChIPmentation and RNA-seq profiling for ten representative samples. Based on the resulting dataset, we devised and applied a bioinformatic method that links chromatin profiles to clinical annotations. Our analysis identified sample-specific variation on top of a shared core of CLL regulatory regions. IGHV mutation status – which distinguishes the two major subtypes of CLL – was accurately predicted by the chromatin profiles, and gene regulatory networks inferred for IGHV-mutated vs. IGHV-unmutated samples identified characteristic differences between these two disease subtypes. In summary, we discovered widespread heterogeneity in the chromatin landscape of CLL, established a community resource for studying epigenome deregulation in leukemia, and demonstrated the feasibility of chromatin accessibility mapping in cancer cohorts and clinical research.

  Study EGAS00001001821

• Epigenetic dynamics of monocyte to macrophage differentiation

  Monocyte to macrophage differentiation involves major biochemical and structural changes in non-dividing cells. In order to elucidate the role of gene regulatory changes during this process, we used high-throughput sequencing to analyze the complete transcriptome and epigenome of human monocytes that were isolated by elutriation and differentiated in vitro by addition of MCSF in serum-free medium. We also investigated the effect of loading the macrophages with modified LDL. We found that many mRNAs and miRNAs were significantly up- or downregulated during differentiation. While there was no correlation between gene expression and DNA methylation changes at transcription start sites, we identified a large number of intra- and intergenic regions that rapidly lost DNA methylation, became nucleosome-free and gained histone marks indicative of active enhancers. Loading of macrophages with modified LDL caused gene expression changes, but no chromatin changes. In summary, our results demonstrate that monocyte to macrophage differentiation is associated with rapid, highly targeted epigenetic changes, whereas lipid uptake mainly affects regulatory circuits of soluble factors.

  Study EGAS00001001595

• Whole genome, transcriptome and methylome profiling enhances actionable target discovery in high-risk paediatric cancer

  Zero Childhood Cancer is a precision medicine program to benefit children with poor-outcome, rare, relapsed or refractory cancer. Utilising tumour and germline whole genome sequencing (WGS) and RNA sequencing (RNAseq) across 252 tumours from high-risk paediatric cancer patients, we identified 968 reportable molecular aberrations (39.9% in WGS and RNAseq, 35.1% WGS-only, 25.0% RNAseq-only). 93.7% of patients had at least one germline or somatic aberration, 71.4% had therapeutic targets and 5.2% had a change in diagnosis. WGS identified pathogenic cancer-predisposing variants in 16.2% of patients. In 76 CNS tumours, methylome analysis confirmed diagnosis in 71.1% and contributed to a change of diagnosis in two cases (2.6%). To date 43 patients have received a recommended therapy, 38 of whom could be evaluated. A small but encouraging proportion of 31% showed some evidence of clinical benefit. Comprehensive molecular profiling resolved the molecular basis of virtually all high-risk cancers, which in some cases has significant clinical impact.

  Study EGAS00001004572

• Hypertension delays viral clearance and exacerbates airway hyperinflammation in patients with COVID-19

  In coronavirus disease 2019 (COVID-19), hypertension and cardiovascular diseases are major risk factors for critical disease progression. However, the underlying causes and the effects of the main anti-hypertensive therapies-angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin receptor blockers (ARBs)-remain unclear. Combining clinical data (n = 144) and single-cell sequencing data of airway samples (n = 48) with in vitro experiments, we observed a distinct inflammatory predisposition of immune cells in patients with hypertension that correlated with critical COVID-19 progression. ACEI treatment was associated with dampened COVID-19-related hyperinflammation and with increased cell intrinsic antiviral responses, whereas ARB treatment related to enhanced epithelial-immune cell interactions. Macrophages and neutrophils of patients with hypertension, in particular under ARB treatment, exhibited higher expression of the pro-inflammatory cytokines CCL3 and CCL4 and the chemokine receptor CCR1. Although the limited size of our cohort does not allow us to establish clinical efficacy, our data suggest that the clinical benefits of ACEI treatment in patients with COVID-19 who have hypertension warrant further investigation.

  Study EGAS00001004772

• RNA-seq study of a Princess Margaret Cancer Centre human acute myeloid leukemia patient cohort

  The PMCC AML RNAseq dataset consists of 81 AML patient samples (clinical data in Supplemental Table 11 of manuscript), processed in two batches. These patient samples are able to engraft in the NSG (NOD.Cg PrkdcscidIl2rgtm1Wjl /SzJ) mouse model. Five patients (90543, 598, 90240, 110484, 100500) were included in both batches. Viaably frozen material from the Leukemia Tissue Bank at Princess Margaret Cancer Centre/ University Health Network were thawed by dropwise addition of X-VIVO + 50% fetal calf serum supplemented with DNase (100μg/mL final concentration, Roche). RNA was extracted from bulk peripheral blood mononuclear cells (PBMC) using the RNeasy Micro Kit (Qiagen Inc.). A paired-end 76 base-pair flow-cell lane Illumina High seq 2000 yielded an average of 240 million sequence reads aligning to genome per sample at the Genome Sciences Centre, BC Cancer Agency for cohort 1. Cohort 2 was subjected to 125 bp, paired-end RNA-sequencing on the Illumina HiSeq 2500 with an average of 50 million reads/sample at the Centre for Applied Genomics, Sick Kids Hospital.

  Study EGAS00001004792

• The genetic structure of Norway

  The aim of the present study was to describe the genetic structure of the Norwegian population using genotypes from 6369 unrelated individuals with detailed information about places of residence. Using standard single marker- and haplotype-based approaches, we report evidence of two regions with distinctive patterns of genetic variation, one in the far northeast, and another in the south of Norway, as indicated by fixation indices, haplotype sharing, homozygosity and effective population size. We detect and quantify a component of Uralic Sami ancestry that is enriched in the North. On a finer scale, we find that rates of migration have been affected by topography like mountain ridges. In the broader Scandinavian context, we detect elevated relatedness between the mid- and northern border areas towards Sweden. The main finding of this study is that despite Norway’s long maritime history and as a former Danish territory, the region closest to mainland Europe in the south appears to have been the most isolated region in Norway, highlighting the open sea as a barrier to gene flow into Norway.

  Study EGAS00001004826

• atrial appendage RNA-seq in non-, paroxysmal and persistent atrial fibrillation

  Understanding the interconnectedness of structural remodelling processes atrial fibrillation (AF) in patients could identify targets for future therapies. These data include transcriptome sequencing of atrial tissues of patients without AF, with paroxysmal AF and persistent AF (total n=64). In AF patients, epicardial cell gene expression decreased, contrasting with an upregulation of epithelial to mesenchymal transition (EMT) and mesenchymal cell gene expression. Immunohistochemistry demonstrated thickening of the epicardium and an increased proportion of (myo)fibroblast-like cells in the myocardium, supporting enhanced EMT in AF. We furthermore report an upregulation of endothelial cell proliferation, angiogenesis and endothelial signalling. EMT and endothelial cell proliferation concurred with increased interstitial (myo)fibroblast-like cells and extracellular matrix gene expression including enhanced tenascin-c, thrombospondins, biglycan and versican. Morphological analysis discovered increased and redistributed glycosaminoglycans and collagens in the atria of AF patients. Signalling pathways, including cell-matrix interactions, PI3K-AKT and Notch signalling, that could regulate mesenchymal cell activation, were upregulated. These dynamic processes may provide targets to prevent or reverse structural remodelling.

  Study EGAS00001005295

• Circulating Tumor DNA Analysis Detects Minimal Residual Disease and Predicts Recurrence in Patients with Stage II Colon Cancer

  Detection of circulating tumor DNA (ctDNA) after resection of stage II colon cancer may identify those at the highest risk of recurrence and help inform adjuvant treatment decisions. We used massively-parallel-sequencing–based assays to evaluate the ability of ctDNA to detect minimal residual disease in 1046 plasma samples from a prospective cohort of 230 patients with resected stage II colon cancer. In patients not treated with adjuvant chemotherapy, ctDNA was detected post-operatively in 14 of 178 (7.9%) patients, 11 (79%) of whom had recurred at a median follow-up of 27 months; recurrence occurred in only 16 (9.8 %) of the 164 patients with negative ctDNA (HR, 18; 95% confidence interval [CI], 7.9 to 36; P<0.001). In patients treated with chemotherapy, the presence of ctDNA following completion of chemotherapy was also associated with an inferior recurrence-free survival (HR, 11; 95% CI, 1.8 to 68; P=0.001). ctDNA detection after stage II colon cancer resection provides direct evidence of residual disease and identifies patients at very high risk of recurrence.

  Study EGAS00001001839

• HCA_Placental_Infection_Atlas

  HCA Placental Infection Atlas Self-renewing human trophoblast stem cells (hTSC) can give rise to major trophoblast lineages, including syncytiotrophoblast (SCT) and extravillous trophoblast (EVT). hTSC has facilitated the study of placental development and function in vitro. Here, we aim to utilise the hTSC line (HMDMC 20/0005) to study human placental infection and inflammation. This study will provide the opportunity to better understand the pathogenesis of human placenta in the event of infection and inflammation. In brief, differentiated hTSC will be infected with relevant pathogens and stimulated with a panel of inflammatory cytokines. We will use single-cell genomic and spatial approaches to characterise cellular heterogeneity in response to infection or cytokines stimulus. In parallel, we will investigate the interaction between iPSC-derived macrophages with different trophoblast lineages during the course of infection using single-cell genomic and spatial methods. This data is part of a pre-publication release. For information on the proper use of pre-publication data shared by the Wellcome Trust Sanger Institute (including details of any publication moratoria), please see http://www.sanger.ac.uk/datasharing/

  Study EGAS00001004722

• Reference exome data for Australian Aboriginal populations to support health-based research

  Whole exome sequencing (WES) is a popular and successful technology which is widely used in both research and clinical settings. However, there is a paucity of reference data for Aboriginal Australians to underpin the translation of health-based genomic research. Here we provide a catalogue of variants called after sequencing the exomes of 50 Aboriginal individuals from the Northern Territory (NT) of Australia and compare these to 72 previously published exomes from a Western Australian (WA) population of Martu origin. Sequence data for both NT and WA samples were processed using an ‘intersect-then-combine’ (ITC) approach, using GATK and SAMtools to call variants. A total of 289,829 variants were identified in at least one individual in the NT cohort and 248,374 variants in at least one individual in the WA cohort. Of these, 166,719 variants were present in both cohorts, whilst 123,110 variants were private to the NT cohort and 81,655 were private to the WA cohort. Our data set provides a useful reference point for genomic studies on Aboriginal Australians.

  Study EGAS00001003745

• Clonal expansion and epigenetic reprogramming following deletion or amplification of mutant IDH1

  IDH1 mutation is the earliest genetic alteration in low-grade gliomas (LGGs), but its role in tumor recurrence is unclear. Mutant IDH1 drives overproduction of the oncometabolite D-2-hydroxyglutarate (2HG) and a CpG island (CGI) hypermethylation phenotype (G-CIMP). To investigate the role of mutant IDH1 at recurrence, we performed a longitudinal analysis of 50 IDH1 mutant LGGs. We discovered six cases with copy number alterations (CNAs) at the IDH1 locus at recurrence. Deletion or amplification of IDH1 was followed by clonal expansion and recurrence at a higher grade. Successful cultures derived from IDH1 mutant, but not IDH1 wild-type, gliomas systematically deleted IDH1 in vitro and in vivo, further suggestive of selection against the heterozygous mutant state as tumors progress. Tumors and cultures with IDH1 CNA had decreased 2HG, maintenance of G-CIMP, and DNA methylation reprogramming outside CGI. Thus, while IDH1 mutation initiates gliomagenesis, in some patients, mutant IDH1 and 2HG are not required for later clonal expansions.

  Study EGAS00001001854

• Study of pediatric hepatocellular carcinoma caused by bile salt export pump deficiency

  Hepatocellular carcinoma (HCC) is almost invariably associated with an underlying inflammatory state, whose direct contribution to the acquisition of critical genomic changes is unclear. We mapped the acquired genomic alterations in human and mouse HCCs induced by defects in hepatocyte biliary transporters, which expose hepatocytes to bile salts and cause the onset of chronic inflammation that develops into cancer. In both human and mouse cancer genomes we found few somatic point mutations with no impairment of cancer genes, but instead massive gene amplification and rearrangements. This genomic landscape differs greatly from that of virus- and alcohol-associated liver cancer. Copy number gains preferentially occurred at late stages of cancer development and frequently targeted the MAPK signaling pathway, and in particular direct regulators of JNK. The pharmacological inhibition of JNK retarded cancer progression in the mouse. Our study demonstrates that intrahepatic cholestasis leading to hepatocyte exposure to bile acids and inflammation promotes cancer through genomic modifications that can be clearly distinguished from those determined by other etiological factors.

  Study EGAS00001000749

• Genetic control of the transcriptomic response of monocytes to bacterial and viral stimuli assessed by RNA-seq in Africans and Europeans

  Humans differ in the outcome that follows exposure to life-threatening pathogens, yet the extent of population differences in immune responses, and their genetic and evolutionary determinants, remain undefined. Here, we characterized, using RNA-sequencing, the transcriptional response of primary monocytes from Africans and Europeans to bacterial and viral stimuli - ligands activating Toll-like receptors pathways (TLR1/2, TLR4 and TLR7/8) and influenza virus - and mapped expression quantitative trait loci (eQTL). We identify multiple cis- and trans-eQTL that contribute to the marked differences in immune responses detected within and between populations, including a TLR1 master regulator that decreases expression of pro-inflammatory genes in Europeans only. We show that regulatory variants have been privileged targets of natural selection, uncovering evolutionarily advantageous mechanisms, such as attenuated inflammation. Finally, we demonstrate that admixture with Neandertals introduced regulatory variants into European genomes, affecting preferentially responses to viral challenges, and identify archaic haplotypes that contributed to population genetic adaptation.

  Study EGAS00001001895

• Primary prostate Hi-C

  Prostate cancer is a heterogeneous disease whose progression is linked to genome instability. Despite large-scale tumour sequencing efforts, the impact of mutations on the genetic architecture in cancer remains ill-defined due to limited integration of genomics data across dimensions. We addressed this limitation by assessing the impact of structural variants on the chromatin states and the three-dimensional organization across benign and malignant primary prostate genomes. We find high concordance in the three-dimensional genome organization between malignant and benign prostate tissues, arguing for constraints to the three-dimensional genome of prostate tumours. Moreover, we identify structural variants as effectors of changes to focal chromatin interactions, guiding cis-regulatory element hijacking that imposes opposing expression changes on genes found at antipodes of a rearrangement. This leads to the repression of tumour suppressor gene expression and up-regulation of oncogenes, such as at the TMPRSS2-ERG and PMEPA1-ZNF156 loci. Collectively, our results argue that cis-regulatory element hijacking by structural variants overshadows large-scale topological changes to alter gene regulation and promote oncogenesis.

  Study EGAS00001005014

• An essential role for MYB in driving oncogenic EVI1 expression in enhancer-rearranged leukemias

  In acute myeloid leukemia (AML) with inv(3)(q21;q26) or t(3;3)(q21;q26), a translocated GATA2 enhancer drives oncogenic expression of EVI1. We generated an EVI1-GFP AML model and applied an unbiased CRISPR/Cas9 enhancer scan to uncover sequence motifs essential for EVI1 transcription. Using this approach, we pinpoint a single regulatory element in the translocated GATA2 enhancer that is critically required for aberrant EVI1 expression while being dispensable for GATA2 expression from its endogenous locus. This element contains a DNA binding motif for the transcription factor MYB that heavily occupies this site specifically at the translocated allele. MYB knockout as well as peptidomimetic blockade of p300-dependent MYB function resulted in downregulation of EVI1 but not of GATA2. Targeting MYB or mutating its DNA-binding motif within the GATA2 enhancer resulted in myeloid differentiation and cell death, suggesting that interference with MYB-driven EVI1 transcription provides a potential entry point for therapy of inv(3)/t(3;3) AMLs.

  Study EGAS00001004839

• The ICGC-TCGA DREAM Somatic Mutation Calling - Tumour Heterogeneity Challenge

  Tumors are composed of many different cell types, ranging from the normal tissue micro-environment, infiltrating immune cells and tumour cells. This group of tumour cells is itself intrinsically highly heterogeneous, driven by the rapid mutation rate of cancer cells to become a mixture of different sub-populations. These different types of cells, called subclones, have different sets of mutations in their DNA. Because some subclones evolve from others, many subclones share mutations. While it is increasingly easy to determine what mutations are present in the tumor, it remains very difficult to determine which subclones have which mutations. The task of assigning mutations to subclones is called subclonal reconstruction.The ICGC-TCGA DREAM Somatic Mutation Calling - Tumour Heterogeneity Challenge (SMC-Het) is an international effort to improve standard methods for subclonal reconstruction: to quantify and genotype each individual cell population present within a tumor. The goal of this challenge is to identify the best subclonal reconstruction algorithms and to identify the conditions that affect their performance.

  Study EGAS00001002092

• Pilot_experiment_on_functional_genomics_in_osteoarthritis

  The aim of this work is to apply an integrated systems approach to understand the biological underpinnings of large joint (hip and knee) osteoarthritis which culminates in the need for total joint replacement (TJR). In this pilot we will assess the feasibility of the approach in the relevant tissue. We will obtain diseased and non-diseased tissue (cartilage and endochondral bone) following TJR, coupled with a blood sample, from 12 patients. We will generate genotype data on the HumanCoreExome array and will characterise the 12 pairs of diseased and non-diseased tissue samples in terms of methylation (Illumina 450k array), transcription (RNASeq) and expression (quantitative proteomics). The pilot will help assess the feasibility of isolating sufficient levels of starting material for the different approaches, and will instigate the development of analytical approaches to synthesising the resulting data. If successful, it is envisaged that we will proceed with expanding the work to 500 patients in the first year, with a target total sample size of 3,000 in the longer term. The key collaborators in this work are Mark Wilkinson (Sheffield) and Jyoti Choudhary

  Study EGAS00001001213

• Liverpool Preterm Birth Biomarker Study

  Preterm birth is a multifactorial condition defined as birth less than 37 weeks of gestation. This study aimed to identify early pregnancy biomarkers from maternal genome-wide and transcriptome-wide data of women experiencing two types of spontaneous PTB (sPTB): spontaneous preterm birth (SPTB) and preterm premature rupture of membranes (PPROM). Whole blood samples were obtained from women with singleton pregnancies (N=567) recruited at the Liverpool Women’s Hospital at 16 and 20 weeks of gestation. Women with a previous history of sPTB pregnancies <34 weeks were categorised on their index pregnancy outcome as spontaneous preterm birth (SPTB) and preterm premature rupture of membranes (PPROM) or high-risk term control (HTERM, ≥37 weeks). Women with no history of SPTB/PPROM and delivered at term were LTERM (≥39 weeks of gestation). DNA was genotyped on the UK Biobank Axiom™ array (Applied Biosystems™, Thermo Fisher Scientific) and RNA who processed using the Clariom™ D Human assay (Thermo Fisher Scientific). Genome-wide association analysis, differential expression analysis and expression quantitative trait loci (eQTL) were completed.

  Study EGAS00001005076

• WGS of T-cell and NK-cell lymphoma for ICGC (NKTL-SG)

  Lymphomas are malignancies originating from the lymphatic system and there is a worldwide significant increase in incidences of this cancer. Lymphomas can be further classified into 2 categories namely Hodgkin’s (HL), and Non-Hodgkin’s lymphoma (NHL). The latter can be divided further into B, T and NK cell NHL. Peripheral T-cell lymphoma (PTCL) and Natural Killer/ T-cell lymphoma (NKTL) arise from mature T lymphocytes and NK cells. The more common subtypes include NKTL, PTCL not-otherwise-specified (PTCL-NOS), systemic anaplastic large cell lymphoma (ALCL), follicular PTCL (F-PTCL), angioimmunoblastic T-cell lymphoma (AITL) and enteropathy-associated T-cell lymphoma (EATL). Whole genome analyses on T-cell and NK-cell lymphoma samples from various countries to gain a better understanding of the pathogenesis and biology of these tumors. The comprehensive profiling and comparison among patients from various countries with different etiopathogenesis will hopefully facilitate the elucidation of key pathways and underlying molecular mechanisms driving these cancers, opening up novel therapeutic strategies in the future.

  Study EGAS00001002398

• Cell-free DNA TAPS for early cancer detection

  Multimodal, genome-wide characterization of epigenetic and genetic information in circulating cell-free DNA (cfDNA) could enable more sensitive early cancer detection. However, due to technological challenges associated with DNA methylation sequencing in low input cfDNA samples, most studies have been limited by DNA damage caused by bisulfite sequencing, or the qualitative nature of enrichment-based sequencing. Recently, we developed TET-assisted Pyridine Borane Sequencing (TAPS), which is a mild, bisulfite-free method for base-resolution direct DNA methylation sequencing. Here we optimized TAPS for cfDNA (cfTAPS) to provide high-quality and high-depth whole-genome cell-free methylomes. We applied cfTAPS to 85 cfDNA samples from patients with hepatocellular carcinoma (HCC) or pancreatic ductal adenocarcinoma (PDAC) and non-cancer controls. From just 10 ng cfDNA (1-3 mL of plasma), we generated the most comprehensive cfDNA methylome to date. We demonstrated that cfTAPS provides multimodal information about cfDNA characteristics, including DNA methylation, tissue of origin, and DNA fragmentation. Integrated analysis of these epigenetic and genetic features enables accurate identification of early HCC and PDAC.

  Study EGAS00001004962