12322 results for ""statistically+reactive"+taxa+in+microbial+community"

in 27.57 milliseconds.

• Comparison of 3 protocols for deriving pancreatic progenitors from hPSCs (RNA-seq)

  This dataset contains 26 mapped bam files. The samples were generated with 3 different protocols for deriving pancreatic progenitors from hPSC. Three parallel differentiations were performed, all done in a hPSC NKX6.1-GFP reporter line. For each protocol there are three cellular populations: total (presort), GFP+ and GFP- . In summary: 3 differentiations x 3 protocols x 3 cellular populations. We prepared Smart-Seq2 RNA-seq libraries for the 27 samples, 1 sample failed library preparation and is not therefore included in this dataset.

  Dataset EGAD00001004823

• limbal stem cells from Aniridia patients

  Limbal stem cells obtained during penetrating keratoplasty from aniridia patients with congenital aniridia (Lagali Stage 4), limbal tissue was digested in collagenase A solution (4 mg/ml) in keratinocyte serum-free medium (KSFM) (Thermo Fisher Scientific; Waltham, MA) for 20 h at 37 °C. Cell suspensions were filtered through a use of Flowmi® micro strainer (SP Bel-Art; Wayne, NJ). LSC clusters were dissociated with trypsin-EDTA (0.05%) solution and cultivated in KSFM. Medium was refreshed every other day. Subconfluent (80–90%) limbal epithelial cells were harvested at passage 2

  Dataset EGAD00001011124

• Combining dasatinib and IFN-α in CML – immunomodulatory effects linked to treatment response and adverse events

  We pooled 100,000 cells from the 12 scRNA+TCRab-seq samples from peripheral blood from three time points (n=4, samples at 0, 3, and 12 months) to understand the landscape of immune subsets in CML during the course of dasatinib+IFN-α treatment

  Study EGAS00001005049

• Action to Control Cardiovascular Risk in Diabetes (ACCORD-BioLINCC)

  Related StudiesWhole genome and whole exome data is available on a subset of participants with phs001411. ECG signal data is available with phs003562.ObjectivesThe purpose of this study was to determine if intensive glycemic control, multiple lipid management and intensive blood pressure control could prevent major cardiovascular events (myocardial infarction, stroke or cardiovascular death) in adults with type 2 diabetes mellitus. Secondary hypotheses included treatment differences in other cardiovascular outcomes, total mortality, microvascular outcomes, health-related quality of life and cost-effectiveness. BackgroundGlycemia Trial:Patients with type 2 diabetes mellitus die of cardiovascular disease (CVD) at rates two to four times higher than non-diabetic populations of similar demographic characteristics. They also experience increased rates of nonfatal myocardial infarction and stroke. With the growing prevalence of obesity in the United States, CVD associated with type 2 diabetes is expected to become an even greater public health challenge in the coming decades than it is now. Expected increases in event rates will be associated with a concomitant rise in suffering and resource utilization.The ACCORD study investigated whether intensive therapy to target normal glycated hemoglobin (HbA1c) levels would reduce cardiovascular events in patients with type 2 diabetes who had either established cardiovascular disease or additional cardiovascular risk factors when compared to standard therapy (HbA1c between 7.0% and 7.9%). A separate analysis investigated whether reduction of blood glucose concentration decreases the rate of microvascular complications in these patients. Lipid Therapy Trial: Patients with type 2 diabetes mellitus have an increased incidence of atherosclerotic cardiovascular disease attributable, in part, to associated risk factors such as dyslipidemia. This is characterized by elevated plasma triglyceride levels, low levels of high-density lipoprotein (HDL) cholesterol and small, dense low-density lipoprotein (LDL) particles. The ACCORD Lipid Therapy trial was designed to test the effect of a therapeutic strategy that uses a fibrate to raise HDL-C and lower triglyceride levels and uses a statin for treatment of LDL-C reduce the rate of CVD events compared to a strategy that only uses a statin for treatment of LDL-C on cardiovascular outcomes in patients with type 2 diabetes that were at high risk for cardiovascular disease. Blood Pressure Trial: Diabetes mellitus increases the risk of cardiovascular disease at every level of systolic blood pressure. Because cardiovascular risk in patients with diabetes is graded and continuous across the entire range of levels of systolic blood pressure, even at prehypertensive levels, the Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure (JNC 7) recommended beginning drug treatment in patients with diabetes who have systolic blood pressures of 130 mm Hg or higher, with a treatment goal of reducing systolic blood pressure to below 130 mm Hg. There is, however, a paucity of evidence from randomized clinical trials to support these recommendations. The ACCORD Blood Pressure trial tested the effect of a target systolic blood pressure below 120 mm Hg on major cardiovascular events among high-risk persons with type 2 diabetes compared to a strategy that targeted a SBP of EYE Substudy: Diabetic retinopathy, an important microvascular complication of diabetes, is a leading cause of blindness in the United States. Randomized, controlled clinical trials in cohorts of patients with type 1 diabetes and those with type 2 diabetes have shown the beneficial effects of intensive glycemic control and intensive treatment of elevated blood pressure on the progression of diabetic retinopathy. Elevated serum cholesterol and triglyceride levels have been implicated, in observational studies and small trials, as additional risk factors for the development of diabetic retinopathy and visual loss. The ACCORD EYE Substudy evaluated the effects of the ACCORD medical strategies on the progression of diabetic retinopathy in a subgroup of trial patients. MIND Substudy: Studies suggest that older persons with type 2 diabetes have at least twice the likelihood of developing late-life cognitive impairment or dementia compared to those without. The mechanisms underlying these cognitive disorders are increasingly thought to reflect a mixed pathology pattern with contributions from vascular, neurodegenerative and neurovascular processes. Pathophysiological mechanisms that have been described include inflammation, oxidative stress, energy imbalance, protein misfolding, glucocorticoid-mediated effects and differences in genetic susceptibilities. The ACCORD MIND substudy took as a premise that early intervention with the ACCORD therapeutic strategies to improve glycemic control could mitigate the adverse effects of type 2 diabetes on the brain. Participants10,251 participants with type 2 diabetes and HbA1c concentrations of 7.5% or more participated in the trial. Of these patients, 5518 were assigned to the lipid therapy arm and 4733 to the blood pressure arm. EYE Substudy: A subgroup of 2856 participants was evaluated for the effects of the ACCORD interventions at 4 years on the progression of diabetic retinopathy. Participants who, at baseline, had a history of proliferative diabetic retinopathy that had been treated with laser photocoagulation or vitrectomy were excluded. MIND Substudy: A subgroup of 2977 participants was evaluated for cognitive function and brain volume. The ACCORD MIND substudy excluded participants aged Design Participants were randomly assigned to undergo either intensive glycemic control (targeting a glycated hemoglobin level EYE Substudy: EYE Substudy participants were evaluated at two standardized and comprehensive eye examinations for the effects of the ACCORD interventions at 4 years on the progression of diabetic retinopathy by 3 or more steps on the Early Treatment Diabetic Retinopathy Study Severity Scale (as assessed from seven-field stereoscopic fundus photographs, with 17 possible steps and a higher number of steps indicating greater severity) or the development of diabetic retinopathy necessitating laser photocoagulation or vitrectomy. MIND Substudy: The cognitive primary outcome, the Digit Symbol Substitution Test (DSST) score, was assessed at baseline, 20 and 40 months. Total brain volume (TBV), the primary brain structure outcome, was assessed with MRI at baseline and 40 months in a sub-set of 632 patients. All patients with follow-up data were included in the primary analyses. Conclusions Glycemia Trial: As compared with standard therapy, the use of intensive therapy to target normal glycated hemoglobin levels for 3.5 years increased mortality and did not significantly reduce major cardiovascular events. (Action to Control Cardiovascular Risk in Diabetes Study Group, et al.,2008, PMID:18539917). Microvascular Outcomes of the Glycemia Trial: Intensive therapy did not reduce the risk of advanced measures of microvascular outcomes, but delayed the onset of albuminuria and some measures of eye complications and neuropathy. Microvascular benefits of intensive therapy should be weighed against the risk of increased total and cardiovascular disease-related mortality, increased weight gain, and higher risk for severe hypoglycemia. (Ismail-Beigi et al., 2010, PMID: 20594588) Lipid Therapy Trial: The combination of fenofibrate and simvastatin did not reduce the rate of fatal cardiovascular events, nonfatal myocardial infarction or nonfatal stroke, as compared with simvastatin alone. These results do not support the routine use of combination therapy with fenofibrate and simvastatin to reduce cardiovascular risk in the majority of high-risk patients with type 2 diabetes (ACCORD Study Group, et al., 2010, PMID: 20228404). Blood Pressure Trial: In patients with type 2 diabetes at high risk for cardiovascular events, targeting a systolic blood pressure of less than 120 mm Hg, as compared with less than 140 mm Hg, did not reduce the rate of a composite outcome of fatal and nonfatal major cardiovascular events (ACCORD Study Group, et al., 2010, PMID: 20228401). EYE Substudy: Intensive glycemic control and intensive combination treatment of dyslipidemia, but not intensive blood-pressure control, reduced the rate of progression of diabetic retinopathy (ACCORD Study Group, et al., 2010, PMID: 20587587). MIND Substudy: Although significant differences in TBV favored the intensive therapy, cognitive outcomes were not different. Combined with the unfavorable effects on other ACCORD outcomes, MIND findings do not support using intensive therapy to reduce the adverse effects of diabetes on the brain in patients similar to MIND patients (Launer et al., 2011, PMID: 21958949).

  Study phs003551

• Oxidative DNA damage and ubiquitin proteasome system dysfunction underpins neurodegeneration in young adults with a DNA repair disorder

  Xeroderma pigmentosum (XP) is caused by defective nucleotide excision-repair of DNA damage. This results in hypersensitivity to ultraviolet light and increased skin cancer risk, as sunlight-induced photoproducts remain unrepaired. However, many XP patients also display early-onset neurodegeneration, which leads to premature death. The mechanism of neurodegeneration is unknown. Here, we investigate XP neurodegeneration using pluripotent stem cells derived from XP patients and healthy relatives, performing functional multi-omics on samples during neuronal differentiation. We have identified substantially increased levels of 5',8-cyclopurine and 8-oxopurine in XP neuronal DNA secondary to marked oxidative stress. Furthermore, we find endoplasmic reticulum stress is upregulated, and, critically, XP neurons exhibit inappropriate downregulation of the protein clearance ubiquitin-proteasome system (UPS). Chemical enhancement of UPS activity improves phenotypes, albeit inadequately, implying that early detection/prevention strategies are necessary to produce clinically impactful outcomes. Thus, we develop an early detection assay predicting neurodegeneration in at-risk patients.

  Study EGAS50000000160

• Oxidative DNA damage and ubiquitin proteasome system dysfunction underpins neurodegeneration in young adults with a DNA repair disorder

  Xeroderma pigmentosum (XP) is caused by defective nucleotide excision-repair of DNA damage. This results in hypersensitivity to ultraviolet light and increased skin cancer risk, as sunlight-induced photoproducts remain unrepaired. However, many XP patients also display early-onset neurodegeneration, which leads to premature death. The mechanism of neurodegeneration is unknown. Here, we investigate XP neurodegeneration using pluripotent stem cells derived from XP patients and healthy relatives, performing functional multi-omics on samples during neuronal differentiation. We have identified substantially increased levels of 5',8-cyclopurine and 8-oxopurine in XP neuronal DNA secondary to marked oxidative stress. Furthermore, we find endoplasmic reticulum stress is upregulated, and, critically, XP neurons exhibit inappropriate downregulation of the protein clearance ubiquitin-proteasome system (UPS). Chemical enhancement of UPS activity improves phenotypes, albeit inadequately, implying that early detection/prevention strategies are necessary to produce clinically impactful outcomes. Thus, we develop an early detection assay predicting neurodegeneration in at-risk patients.

  Study EGAS50000000162

• Oxidative DNA damage and ubiquitin proteasome system dysfunction underpins neurodegeneration in young adults with a DNA repair disorder

  Xeroderma pigmentosum (XP) is caused by defective nucleotide excision-repair of DNA damage. This results in hypersensitivity to ultraviolet light and increased skin cancer risk, as sunlight-induced photoproducts remain unrepaired. However, many XP patients also display early-onset neurodegeneration, which leads to premature death. The mechanism of neurodegeneration is unknown. Here, we investigate XP neurodegeneration using pluripotent stem cells derived from XP patients and healthy relatives, performing functional multi-omics on samples during neuronal differentiation. We have identified substantially increased levels of 5',8-cyclopurine and 8-oxopurine in XP neuronal DNA secondary to marked oxidative stress. Furthermore, we find endoplasmic reticulum stress is upregulated, and, critically, XP neurons exhibit inappropriate downregulation of the protein clearance ubiquitin-proteasome system (UPS). Chemical enhancement of UPS activity improves phenotypes, albeit inadequately, implying that early detection/prevention strategies are necessary to produce clinically impactful outcomes. Thus, we develop an early detection assay predicting neurodegeneration in at-risk patients.

  Study EGAS50000000158

• Karyotype Evolution in Response to Chemoradiotherapy and Upon Recurrence of Esophageal Adenocarcinomas

  The genome of esophageal adenocarcinoma (EAC) is highly unstable and might evolve over time. Here, we track karyotype evolution in EACs in response to treatment and upon recurrence through multi-region and longitudinal analysis. To this end, we introduce L-PAC, a bio-informatics technique that allows inference of absolute copy number aberrations (CNA) of low-purity samples by leveraging information of high-purity samples from the same cancer. Quantitative analysis of matched absolute CNAs reveals that the amount of karyotype evolution induced by chemoradiotherapy (CRT) is predictive for early recurrence and depends on the initial level of karyotype intra-tumor heterogeneity. We observe that CNAs acquired in response to CRT are partially reversed back to the initial state upon recurrence. CRT hence alters the fitness landscape to which tumors can adjust by adapting their karyotype. Together, our results indicate that karyotype plasticity contributes to therapy resistance of EACs.

  Study EGAS00001007711

• Improved detection of colibactin-induced mutations by genotoxic E. coli in organoids and colorectal cancer

  Co-culture of intestinal organoids with a colibactin-producing pks+ E. coli strain (EcC) revealed mutational signatures also found in colorectal cancer (CRC). E. coli Nissle 1917 (EcN) remains a commonly used probiotic, despite harboring the pks operon and inducing double strand DNA breaks. We determine the mutagenicity of EcN and three CRC-derived pks+ E. coli strains with an analytical framework based on sequence characteristic of colibactin-induced mutations. All strains, including EcN, display varying levels of mutagenic activity. Furthermore, a machine learning approach attributing individual mutations to colibactin reveals that patients with colibactin-induced mutations are diagnosed at a younger age and that colibactin can induce a specific APC mutation. These approaches allow the sensitive detection of colibactin-induced mutations in ~12% of CRC genomes and even in whole exome sequencing data, representing a crucial step towards pinpointing the mutagenic activity of distinct pks+ E. coli strains.

  Study EGAS50000000212

• Genome-Wide Association Study of Endometrial Cancer in the Epidemiology of Endometrial Cancer Consortium (E2C2)

  Endometrial cancer, the most common gynecological malignancy in the United States, has both an environmental and genetic component. To this end, we conducted a genome-wide association study to identify genes involved in endometrial cancer using studies from the NCI-supported Epidemiology of Endometrial Cancer Consortium (E2C2). For the discovery stage we included samples from 6 cohort and 7 case control studies through 2007. The total number of cases genotyped were 2,307, white women of European descent, and 2,307 matched controls using the Illumina HumanOmniExpress platform. We conducted the replication using the Infinium HumanExome BeadChip, which successfully genotyped 177,139 variants in 1055 cases and 1778 controls from four ethnically diverse studies that are part of the Epidemiology of Endometrial Cancer Consortium (E2C2). The overall goal is to determine whether certain genotypes are predictive of future endometrial cancer risk, and whether the genotypes interact with established endometrial risk factors.

  Study phs000893

• Differential Transcription Start Site Usage in Brain-related Samples

  RNA-Seq is an effective method to study the transcriptome, but specialized methods are required to identify 5' ends of transcripts. Several published strategies exist for this specific purpose, but their relative merits have not been systematically analyzed. Here, we directly compare the performance of six such methods - testing five with cellular RNA as well as a novel spike-in RNA assay that helps address interpretation challenges that arise from uncertainties in annotation or RNA processing. Using a single human RNA sample, we constructed and sequenced 18 libraries with these methods and one standard, control RNA-Seq library. We find that the CAGE method performed best for mRNA and that most of its unannotated peaks are supported by evidence from other genomic methods. We then applied CAGE to eight brain-related samples and revealed sample-specific transcription start site (TSS) usage as well as a transcriptome-wide shift in TSS usage between fetal and adult brain.

  Study phs001463

• Interpreting molecular role of DNA variants associated with Crohn's Disease through integrative analysis of open chromatin, epigenome and transcriptome data in diverse and relevant tissues and cells

  Crohn's disease (CD), one of the two major inflammatory bowel diseases (IBD), results from an inappropriately directed inflammatory response to the enteric microbiota in a genetically susceptible host. Genome wide association studies (GWAS) have linked >200 specific single nucleotide polymorphisms (SNPs) to CD disease pathogenesis. Within these regions, there are over 5600 additional SNPs that are in linkage disequilibrium (LD) with the tag SNPs, and it is not known which of these contribute to CD. Most of these SNPs map to non-coding regions of the genome, suggesting that causal variants contribute to CD by modifying gene regulatory element activity. In ths study, we have generated genotype, open chromatin (FAIRE-seq), and transcriptome (RNA-seq) data from macroscopically uninflamed regions of colon tissue for 21 CD patients and 11 non-IBD controls. All patients are adults (>18 years old).

  Study phs001418

• Single-cell Profiling of an In Vitro Model of Human Interneuron Development Reveals Temporal Dynamics of Cell Type Production and Maturation

  GABAergic interneurons are essential for neural circuit function and their loss or dysfunction is implicated in human neuropsychiatric disease. In vitro methods for interneuron generation hold promise for studying human cellular and functional properties and ultimately therapeutic cell replacement. We used a protocol for generating cortical interneurons from hESCs and analyzed the properties and maturation timecourse of cell types using single-cell RNAseq (data available at GEO under: GSE93802 on March 10 2017). Transcriptomic profiles of the hESC-derived interneurons were compared to several different populations of cells from mid-gestation human neocortex that showed differing levels of PAX6 and SOX2 expression. For this study, 104 samples of 100 human neocortical cells each, have been sorted based on SOX2 and PAX6 expression, mRNA recovered from the fixed cells by FRISCR, and transcriptomic profiles generated by SmartSeq2. The RNA-seq data from the 104 100-cell samples is included in this dbGaP study.

  Study phs001276

• Genetic Control of Expression and Splicing in Developing Human Brain

  Most genetic risk for human diseases lies within non-coding regions of the genome that are predicted to regulate gene expression in a tissue- and stage-specific manner. Given the importance of regulatory pathways during brain development, we characterized the genetic control of the transcriptome in 201 mid-gestational human brains, identifying 7962 eQTL and 4635 sQTL. By integration with GWAS, we characterized the genes and isoforms contributing to specific neuropsychiatric disorders, including SCZ and ASD, as well as other cognition or behavioral-related phenotypes. SCZ and ASD impact distinct developmental gene co-expression modules, yet in both disorders, common and rare genetic variation converge. These analyses demonstrate the highly distinctive effects of transcriptional control, as well as divergent age-related contributions to disease. More broadly, these findings demonstrate the genetic mechanisms by which early developmental events have a striking and widespread influence on adult anatomical and behavioral phenotypes.

  Study phs001900

• Immune Response to Life-Threatening Respiratory Infections in Children and Young Adults

  This is a cross sectional study describing age-related differences in the nasal mucosal immune response to SARS-CoV-2. We collected nasal mucosal samples from six groups: healthy children, children infected with SARS-CoV-2, children infected with respiratory syncytial virus, children infected with influenza virus, healthy adults, and adults infected with SARS-CoV-2. Samples were obtained by mucosal scrape biopsy of the inferior turbinate using a sterile plastic curette. We performed bulk RNA-sequencing to obtain gene expression data. Clinical data was extracted from the electronic health record including: demographics, medical history, clinical presentation, duration of symptoms, intensive care unit admission, hospital and intensive care unit length of stay, type and duration of respiratory support at sample collection and peak illness. Our analysis described the host response to SARS-CoV-2 in the nasal mucosa in children and adults and compared it to the host response to respiratory syncytial virus and influenza virus.

  Study phs002579

• Unraveling the Genetic Architecture of Diabetic Retinopathy in South India

  This study aims to understand the genetic architecture of diabetic retinopathy in the South Indian population by examining participants with South Indian ancestry and type 2 diabetes (T2D) from two sources: the Sankara Nethralaya-Diabetic Retinopathy Epidemiology and Molecular Genetic Study (SN-DREAMS) and prospective recruitment at Sankara Nethralaya affiliates. A total of 2393 patients were recruited and included in the genetic analysis, with 1588 patients having no diabetic retinopathy (DR) serving as the controls and 805 patients with any level of DR serving as the cases. Enrolled individuals had genome-wide genotyping from DNA extracted from blood samples. In addition, whole genome sequencing (WGS) was performed on 31 members from 2 families. Clinical data, such as age, duration of diabetes, and hemoglobin A1C (HbA1c) were recorded for study participants. Diabetic retinopathy was assessed by clinical exam and/or fundus photography. The grading of diabetic retinopathy followed the International Clinical Diabetic Retinopathy Severity Scale.

  Study phs002116

• Identification of High-Risk PHF19 Expressing Cells in Myeloma Single-Cell Multiomics

  The aim of this study is to identify novel subsets of cells that are associated with progression and response to treatment. In this project, we study the tumor fraction from 49 myeloma patients across stages of progression. Samples were collected from 10 smoldering multiple myeloma (SMM), 22 newly diagnosed multiple myeloma (NDMM), and 17 relapsed refractory multiple myeloma (RRMM) patients. These samples were then sorted using magnetic-activated cell sorting (MACS) for CD138+ cells that represent the tumor fraction of each sample. The CD138+ fraction then underwent whole genome sequencing (WGS), where possible, and single-cell multiomics. Single-cell multiomics can now measure scRNA-seq and scATAC-seq simultaneously, which we use in this project. Using single-cell multiomics, we will study subclonal changes in gene expression, chromatin accessibility, and identify novel regulatory relationships within myeloma tumors. Furthermore, we will apply state of the art single-cell and single-cell multiomic techniques to better identify the more high-risk components of myeloma.

  Study phs003220

• Spatial atlas of human atherosclerosis highlights role of the microvasculature in disease

  Atherosclerosis is a pervasive contributor to ischemic heart disease and stroke. Despite the advance of lipid lowering-therapies and antihypertensive agents, the residual risk of an atherosclerotic event remains high and developing therapeutic strategies has proven challenging. This is due to the complexity of atherosclerosis with a spatial interplay of multiple cell types within the vascular wall. Here we generate an integrative high-resolution map of human atherosclerotic plaques combining single-cell RNA-seq from multiple studies and spatial transcriptomics data from 12 human specimens, with different stages of atherosclerosis. We show cell-type and atherosclerosis-specific expression changes and spatially constrained alterations in cell-cell communication. We highlight the possible recruitment of lymphocytes via ACKR1 endothelial cells of the vasa vasorum, the migration of vascular smooth muscle cells towards the lumen by transforming into fibromyocytes, and cell-cell communication in the plaque region, indicating an intricate cellular interplay within the adventitia and the subendothelial space in human atherosclerosis.

  Study EGAS50000000660

• Single-cell transcriptional mapping reveals genetic and hierarchy-based determinants of aberrant differentiation in AML

  Therapeutic targeting of acute myeloid leukemia (AML) has in part been hampered by profound cell state heterogeneity among leukemia cells. To develop a more precise understanding of leukemia cell states in AML, we constructed a reference atlas of human hematopoiesis from 263,519 single cell transcriptomes spanning 55 cellular states. Using this atlas, we mapped over 1.2 million single-cell transcriptomes spanning 318 myeloid leukemia samples. This uncovered twelve recurrent patterns of aberrant differentiation in AML and additional leukemia cell states involving lymphoid and erythroid progenitors. Systematic mapping of genotype-to-phenotype associations revealed specific differentiation landscapes associated with >45 genetic drivers. Importantly, AML samples sharing common genetic driver alterations can have distinct cellular origins which inform the cellular identity of their disease-sustaining leukemia stem cell (LSC). Further, distinct LSC-driven hierarchies can co-exist within individual patients. Thus, precise mapping of malignant cell states provides insights into leukemogenesis, refines disease classification, and informs therapy development.

  Study EGAS50000000918

• Spatial Transcriptomics Uncovers Tumor Microenvironment-Based Subtypes in Invasive Lobular Carcinoma

  Invasive lobular carcinoma (ILC) is the second most common histological subtype of breast cancer (BC); however, little is known about its tumor microenvironment (TME). Here, we investigated the spatial architecture of 43 hormone-receptor-positive, HER2-negative (HR+/HER2-) primary ILC samples, using spatial transcriptomics and detailed morphological annotation. By integrating morphology, spatial, and single-cell data, we mapped TME-related cell types, exploring their proximity to tumor cells and their enrichment in specific compartments. Clustering of spatial transcriptomics spots revealed significant inter- and intra-tumor heterogeneity, identifying pathways and cell types linked with disease outcomes. Morphological and gene expression data were finally integrated with a multimodal approach, leading to the identification of 4 new ILC subtypes based on TME heterogeneity. By using derived, specific gene expression signatures, these subtypes were identified and validated in external bulk RNA-seq/microarray datasets (SCAN-B and METABRIC), where differences in prognosis emerged.

  Study EGAS50000001001

• Transcriptome changes in circulating immune cells of critical COVID-19 patients predict a specific metabolic and epigenetic imprint

  The progression to severe COVID-19 arises predominantly from a dysregulated host immune response, although the underlying regulatory mechanisms still remain partially elusive. This limits a prompt prediction of disease progression and restrains our understanding of “long COVID”. Here, we analyzed the transcriptomes of peripheral blood mononuclear cells collected from COVID-19 patients experiencing different degrees of the disease and control patients. In critical COVID-19 patients, we found an altered regulatory network involving microRNAs, long non-coding RNAs, and coding genes that control mRNA translation-related genes, epigenetics, and metabolism. We also observed an upregulation of tRNA aminoacylation genes and increased expression of coding genes enriched for the cognate amino acids. Collectively, our findings indicate a broad perturbation of the gene expression landscape that characterizes the aberrant host immune response in critical COVID-19 patients and is potentially coordinated by alterations in microRNA expression and tRNA metabolism.

  Study EGAS50000000965

• Lenalidomide Resistance in del(5q) Myelodysplastic Syndrome Follows Loss of RUNX1/TP53-mediated Megakaryocytic Differentiation

  Interstitial deletion of the long arm of chromosome 5 (del(5q)) is the commonest structural genomic variant in myelodysplastic syndromes (MDS). Lenalidomide (LEN) is the treatment of choice for patients with del(5q) MDS, but half of the responding patients become resistant within two years. TP53 mutations are detected in ~20% of patients who become resistant to LEN. Our data show that patients who become resistant to LEN harbor either TP53 or RUNX1 mutations or loss of RUNX1 expression. Here we show that LEN-induced degradation of IKZF1 permits a RUNX1/GATA2 complex to drive megakaryocytic differentiation and consequent del(5q) MDS progenitor cell death via CRBN-mediated CSNK1A1 degradation. Overexpression of GATA2 is able to restore LEN sensitivity in the context of RUNX1 or TP53 mutations by enhancing LEN-induced megakaryocytic differentiation. Screening for TP53 and RUNX1 mutations or downregulation should identify patients resistant to LEN, and strategies to activate GATA2 may resensitize del(5q) MDS cells to LEN

  Study EGAS00001004113

• Myelodysplastic cells in patients re-program mesenchymal stromal cells to establish a transplantable stem cell-niche disease unit.

  Myelodysplastic syndromes (MDS) are a heterogeneous group of myeloid neoplasms with defects in hematopoietic stem/progenitor cells (HSPCs) and possibly the HSPC niche. Here we show that patient-derived mesenchymal stromal cells (MDS MSCs) display a disturbed differentiation program and are essential for the propagation of MDS-initiating lin-CD34+CD38- stem cells in orthotopic xenografts. Overproduction of niche factors such as N-Cadherin, IGFBP2, VEGFA and LIF is associated with the ability of MDS MSCs to enhance MDS expansion. These factors represent putative therapeutic targets to disrupt critical hematopoietic-stromal interactions in MDS. Finally, healthy MSCs adopt "MDS-MSC like" molecular features when exposed to hematopoietic MDS cells, indicative of an instructive remodeling of their microenvironment. This patient-derived xenograft model therefore provides functional and molecular evidence that MDS is a complex disease involving both the hematopoietic and stromal compartments. The resulting deregulated expression of niche factors may well also be a feature of other hematopoietic malignancies.

  Study EGAS00001000716

• Whole exome sequencing for gallbladder cancer in Xinhua Hospital Affiliated to Shanghai Jiao Tong University, School of Medicine

  Patients with gallbladder carcinoma (GBC), the most aggressive malignancy of the biliary tract, have a poor prognosis. Here, we report our identification of somatic mutations of GBCs in 57 tumor-normal pairs by use of a combination of exome sequencing and ultra-deep sequencing of cancer-related genes. The mutation pattern is defined by a dominative prevalence of C>T mutations at TCN sites. Genes with a significant frequency of non-silent mutations include TP53 (47.1%), KRAS (7.8%), and ERBB3 (11.8%). Moreover, ErbB signaling (including EGFR, ERBB2, ERBB3, ERBB4 and their downstream genes) is the most extensively mutated pathway, affecting 36.8% (21 of 57) of the GBC samples. Multivariate analyses further reveal that patients with ErbB pathway mutations have a worse outcome (P = 0.001). These findings provide insight into the somatic mutational landscape in GBC and highlight the key role of the ErbB signaling pathway in the pathogenesis of GBCs.

  Study EGAS00001000853

• Novel paediatric case of a spinal high-grade astrocytoma with piloid features in a patient with Noonan Syndrome

  Noonan Syndrome (NS) is associated with an increased risk of low-grade central nervous system tumours in children but only very rarely associated with high-grade gliomas. Here we describe the first reported case of a spinal high-grade astrocytoma with piloid features (HGAP) in a child with NS. This case was a diagnostic and treatment dilemma, prior to whole-genome germline and tumour sequencing, tumour transcriptome sequencing and DNA methylation analysis. The methylation profile matched strongly with HGAP and sequencing identified somatic FGFR1 and NF1 variants and a PTPN11 germline pathogenic variant. Therapeutic targets were identified but also alterations novel to HGAP such as differential expression of VEGFA and PD-L1. The germline PTPN11 finding has not been previously described in individuals with HGAP.  This case underscores the power of precision medicine from a diagnostic, therapeutic and clinical management perspective, and describes an association between HGAP and NS which has not previously been reported.

  Study EGAS00001007937

• Transcriptome analysis in very preterm infants with chronic lung disease after birth

  Bronchopulmonary dysplasia (BPD) is the most common complication of prematurity and is characterized by impaired alveolar and vascular development. The aim of the study was to identify early BPD-relevant pathways by applying whole genome transcriptional profiling combined with protein measurements from umbilical arterial blood samples of preterm infants with and without BPD. Only newborn infants <32 weeks gestational age (GA) were prospectively included in this study. Blood was obtained from an indwelling umbilical artery catheter at birth and after 72 hours after birth and subjected to gene expression analysis using the Codelink Human I 10k Bioarray and the the Codelink Human Whole Genome Bioarray. The study reveals a monocyte-centered immune response at birth characterizing preterm infants later developing BPD. The findings provide potential markers for early risk stratification in the preterm infant with respect to the development of chronic pulmonary disease and may subsequently enable the development of new treatment strategies in this high risk patient cohort.

  Study EGAS00001002586

• Tracking the origins and drivers of subclonal metastatic expansion in prostate cancer

  Tumour heterogeneity in primary prostate cancer is a well-established phenomenon. However, how the subclonal diversity of tumours changes during metastasis and progression to lethality is poorly understood. Here we reveal the precise direction of metastatic spread across four lethal prostate cancer patients using whole-genome and ultra-deep targeted sequencing of longitudinally collected primary and metastatic tumours. We find one case of metastatic spread to the surgical bed causing local recurrence, and another case of cross-metastatic site seeding combining with dynamic remoulding of subclonal mixtures in response to therapy. By ultra-deep sequencing end-stage blood, we detect both metastatic and primary tumour clones, even years after removal of the prostate. Analysis of mutations associated with metastasis reveals an enrichment of TP53 mutations, and additional sequencing of metastases from 19 patients demonstrates that acquisition of TP53 mutations is linked with the expansion of subclones with metastatic potential which we can detect in the blood.

  Study EGAS00001000942

• Translation of non-canonical open reading frames as a cancer cell survival mechanism in childhood medulloblastoma

  A hallmark of high-risk childhood medulloblastoma is the dysregulation of RNA translation. Currently, it is unknown whether medulloblastoma dysregulates the translation of putatively oncogenic non-canonical open reading frames. To address this question, we performed ribosome profiling of 32 medulloblastoma tissues and cell lines and observed widespread non-canonical ORF translation. We then developed a step-wise approach to employ multiple CRISPR-Cas9 screens to elucidate functional non-canonical ORFs implicated in medulloblastoma cell survival. We determined that multiple lncRNA-ORFs and upstream open reading frames (uORFs) exhibited selective functionality independent of the main coding sequence. One of these, ASNSD1-uORF or ASDURF, was upregulated, associated with the MYC family oncogenes, and was required for medulloblastoma cell survival through engagement with the prefoldin-like chaperone complex. Our findings underscore the fundamental importance of non-canonical ORF translation in medulloblastoma and provide a rationale to include these ORFs in future cancer genomics studies seeking to define new cancer targets.

  Study EGAS00001007426

• SG10K_Pilot - Large-scale whole-genome sequencing of three diverse Asian populations in Singapore

  Underrepresentation of Asian genomes has hindered population and medical genetics research on Asians, leading to population disparities in precision medicine. By whole-genome sequencing of 4,810 Singapore Chinese, Malays, and Indians, we found 98.3 million SNPs and small insertions/deletions, over half of which are novel. Population structure analysis demonstrated great representation of Asian genetic diversity by three ethnicities in Singapore, and revealed a Malay-related novel ancestry component. Furthermore, demographic inference suggested that Malays split from Chinese ~24,800 years ago, and experienced significant admixture with East Asians ~1,700 years ago, coinciding with the Austronesian expansion. Additionally, we identified 20 candidate loci for natural selection, among which 14 harbored robust associations with complex traits and diseases. Finally, we showed that our data can substantially improve genotype imputation in diverse Asian and Oceanian populations. These results highlight the value of our data as a resource to empower human genetics discovery across broad geographic regions.

  Study EGAS00001003875

• Single-cell chromatin accessibility landscape identifies tissue repair program in human regulatory T cells

  Studies over the past decade characterized murine regulatory T cells (Tregs) with the capacity to promote tissue regeneration. In humans, such a population of tissue-repair Treg cells has not been discovered yet. Using single-cell chromatin accessibility profiles of murine and human tissue Treg cells, we defined a species-conserved and microbiota-independent repair Treg signature, with a prevailing footprint of the transcription factor BATF. Combining this signature with gene expression profiling and TCR fate mapping, we identified a population of tissue-like Treg cells in peripheral blood, characterized by the expression of BATF, CCR8 and HLA-DR. Human BATF+CCR8+ Treg cells from normal skin and adipose tissue shared features with tumor-resident Treg and tissue T-follicular helper (Tfh) cells. Inducing a Tfh-like differentiation program in naive Treg cells partially recapitulated human tissue Treg characteristics, including enhanced wound healing potential

  Study EGAS00001004900

• Data from the paper Context-specific Effects of TGFβ/SMAD3 in Cancer Are Modulated by the Epigenome. Tufegdzic et al, Cell Reports 2015

  The transforming growth factor beta (TGFβ) signalling pathway exerts opposing effects on cancer cells, acting either as a tumor-promoter or as a tumor-suppressor. Here we show these opposing effects are a result of the synergy between SMAD3, a downstream effector of TGFβ signalling, and the distinct epigenomes of breast tumor initiating cells (BTICs). These effects of TGFβ are associated with distinct gene expression programs, but genomic SMAD3 binding patterns are highly similar in the BTIC-promoting and BTIC- suppressing contexts. Our data show cell type-specific epigenetic configurations provide a modulatory layer by determining accessibility of genes to regulation by TGFβ/SMAD3. LBH, one such context-specific target gene, is regulated according to its DNA methylation status, and is crucial for TGFβ-dependent promotion of BTICs. Overall, these results reveal that the epigenome plays a central and previously overlooked role in shaping the context-specific effects of TGFβ in cancer.

  Study EGAS00001001570

• Systematic kinase inhibitor profiling identifies CDK9 as a synthetic lethal target in NUT midline carcinoma

  Kinase inhibitors represent the backbone of targeted cancer therapy, yet only a limited number of oncogenic drivers are directly druggable. By interrogating the activity of 1,505 kinase inhibitors we found that BRD4-NUT-rearranged NUT midline carcinoma (NMC) cells are specifically killed by CDK9 inhibition (CDK9i) and exhibit a unique dependency on CDK9 and Cyclin-T1 expression. We show that CDK9i leads to robust induction of apoptosis and of markers of DNA damage response in NMC cells. While both CDK9i and bromodomain inhibition over time result in reduced Myc protein expression, only bromodomain inhibition induces cell differentiation and a p21-induced cell cycle arrest in these cells. Finally, RNA-Seq and ChIP-based analyses reveal a BRD4-NUT specific CDK9i-induced perturbation of transcriptional elongation. Thus, our data provide a mechanistic basis for the genotype-dependent vulnerability of NUT midline carcinoma cells to CDK9i that may be of relevance for the development of targeted therapies for NMC patients.

  Study EGAS00001002588

• The interface of malignant and immunologic clonal dynamics in high-grade serous ovarian cancer

  High-grade serous ovarian cancer exhibits extensive intratumoral heterogeneity coupled with widespread intraperitoneal disease. Despite this, metastatic spread of tumor clones is non-random, implying the existence of local microenvironmental factors that shape tumor progression. We interrogated the molecular interface between tumorinfiltrating lymphocytes (TIL) and cancer cells in 143 samples from 21 patients using whole-genome sequencing, immunohistochemistry, histologic image analysis, gene expression profiling, and T- and B-cell receptor sequencing. We identify 3 immunologic response categories, which frequently co-exist within individual patients. Furthermore, epithelial CD8+ TIL were inversely associated with malignant cell diversity, evidenced by subclonal neoepitope elimination and spatial tracking between tumor and T-cell clones. Intersecting mutational signatures and immune analysis showed that foldback inversion genomic aberrations lead to worse outcomes even in the presence of cytotoxic TIL (n=433). Thus, regional variation in immune contexture mirrors the pattern of intraperitoneal malignant spread, provoking new perspectives for treatment of this challenging disease.

  Study EGAS00001002839

• High number of somatic mutations found in the healthy blood compartment of a 115-year-old woman reveals oligoclonal hematopoiesis

  The somatic mutation burden in healthy white blood cells (WBCs) is not well known. Based on deep whole genome sequencing, we estimate that ~450 somatic mutations accumulated in the non-repetitive genome within the healthy blood compartment of a 115-year old woman. The detected mutations appear to have been harmless passenger mutations: they were enriched in non-coding, AT-rich regions that are not evolutionarily conserved, and they were depleted for genomic elements where mutations might have favorable or adverse effects on cellular fitness, such as regions with actively transcribed genes.The distribution of variant allele frequencies of these mutations suggests that the majority of the peripheral white blood cells were offspring of two related hematopoietic stem cell (HSC) clones. Moreover, telomere lengths of the WBCs were significantly shorter than telomere lengths from other tissues. Together, this suggests that the finite lifespan of HSCs, rather than somatic mutation effects, may lead to hematopoietic clonal evolution at extreme ages.

  Study EGAS00001000660

• Spatial and Temporal Homogeneity of Driver Mutations in Diffuse Intrinsic Pointine Glioma

  Diffuse Intrinsic Pontine Gliomas (DIPG) are deadly pediatric brain tumors where needle biopsies help guide diagnosis and targeted therapies. To address spatial heterogeneity, we analyzed 134 specimens from various neuroanatomical structures of whole autopsy brains from nine DIPG patients. Evolutionary reconstruction indicates histone 3 (H3)K27M – including novel H3.2K27M - mutations potentially arise first and are invariably associated with specific, high-fidelity obligate partners throughout the tumor and its spread, from diagnosis to end-stage disease, suggesting mutual need for tumorigenesis. These H3K27M ubiquitously-associated mutations involve alterations in TP53 cell-cycle (TP53/PPM1D) or specific growth factor pathways (ACVR1/PIK3R1). Later oncogenic alterations arise in sub-clones and often affect the PI3K pathway. Our findings are consistent with early tumor spread outside the brainstem including the cerebrum. The spatial and temporal homogeneity of driver mutations in DIPG implies they will be captured by limited biopsies and emphasizes the need to develop therapies specifically targeting obligate oncohistone partnerships.

  Study EGAS00001001654

• A novel TP53-KPNA3 translocation defines a de novo treatment-resistant clone in osteosarcoma

  Osteosarcoma is the most common primary bone cancer. It can be cured by aggressive surgery and chemotherapy, but outcomes for metastatic or chemoresistant disease remain dismal. Cancer sequencing studies have shown that the p53 pathway is dysregulated in nearly every case, often by translocation; however, no studies of osteosarcoma evolution or intratumor heterogeneity have been done to date. We studied a patient with chemoresistant, metastatic disease over the course of three years. We performed exome sequencing on germline DNA and DNA collected from tumor at three separate timepoints. We compared variant calls and variant allele frequencies between different samples. We identified subclonal driver mutations in several different genes in the primary tumor sample and found that one particular subclone dominated subsequent tumor samples at relapse. This clone was marked by a novel TP53-KPNA3 translocation and loss of the opposite-strand wild-type TP53 allele. Future research must focus on functional significance of such clones and strategies to eliminate them.

  Study EGAS00001001805

• Hi-C dataset for testicular germ cell tumour GWAS risk loci, as described in the Oncoarray Litchfield et al. 2016 paper.

  Genome-wide association studies (GWAS) have transformed our understanding of testicular germ cell tumour (TGCT) susceptibility but much of the heritability remains unexplained. Here we report a new GWAS, a meta-analysis with previous GWAS and a replication series, totalling 7,319 TGCT cases and 23,082 controls. We identify 19 new TGCT risk loci, approximately doubling the number of known TGCT risk loci to 44. By performing in-situ Hi-C in TGCT cells, we establish a network of physical interactions between all 44 TGCT risk SNPs and candidate causal genes. Our findings reveal widespread disruption of developmental transcriptional regulators as a basis of disease susceptibility, consistent with failed primordial germ cell differentiation as an initiating step in TGCT oncogenesis1. Defective microtubule assembly and dysregulation of KIT-MAPK signalling also feature as recurrently disrupted pathways. Our findings support a polygenic model of disease risk and provide insight into the biological basis of TGCT.

  Study EGAS00001001930

• Immune trajectory of response and adverse effect in immunotherapy-treated hepatocellular carcinoma

  Whilst anti-PD1 immune checkpoint blockade (ICB) has revolutionised treatment for many cancers, its response rates in hepatocellular carcinoma (HCC) remain modest, coupled with common incidences of immune-related adverse events (irAEs). To identify biomarkers and decipher the mechanisms for response and irAEs, we performed multi-dimensional immunoprofiling on peripheral blood and tissue collected before and during anti-PD1 ICB treatment from HCC patients. Single-cell analyses enabled us to identify peripheral biomarkers, in particular, CD11c+ antigen-presenting cells with varying degrees of HLA-DR expression and CD8 effector memory (EM) T cells with CXCR3 tissue-homing capability that are associated with both response and irAEs. We also dissected the mechanisms behind how these immune subsets interface between response and toxicity, showing their intersecting yet diverging trajectories leading to these distinct clinical fates. This study offers new insights on the mechanisms and potentially novel strategies to enhance response and ameliorate irAEs in cancer immunotherapy.

  Study EGAS00001004843

• The Acquisition of Molecular Drivers in Pediatric Therapy-Related Myeloid Neoplasms

  Pediatric therapy-related myeloid neoplasms (tMN) occur in children after exposure to cytotoxic therapy and have a dismal prognosis1-4. The somatic and germline genomic alterations that drive these myeloid neoplasms in children and how they arise have yet to be comprehensively described. We use whole exome, whole genome, and/or RNA sequencing to characterize the genomic profile of 85 pediatric tMN cases (tMDS: n=29, tAML: n=56). Our data show that Ras/MAPK pathway mutations, alterations in RUNX1 or TP53, and KMT2A rearrangements are frequent somatic drivers, and we identify cases with aberrant MECOM expression secondary to enhancer hijacking. Unlike adults with tMN5-7, we find no evidence of pre-existing minor tMN clones (including those with TP53 mutations), but rather the majority of cases were unrelated clones arising as a consequence of cytotoxic therapy. These studies also uncover rare cases of lineage switch disease rather than true secondary neoplasms.

  Study EGAS00001004850

• Interethnic comparability in blood pressure GWAS

  We carried out a genome-wide association and replication study for blood pressure in a two-stage approach (max N = 289,038) with a discovery stage sample of 130,777 East Asian individuals, identifying 19 new genetic loci. We found a significant genetic heterogeneity between East Asian and European-descent populations at several blood pressure loci, conforming to “a common ancestry-specific variant association model”. At 6 unique loci, distinct non-rare (or common) ancestry-specific variants co-localized within the same linkage disequilibrium block despite the significantly discordant direction of effects for the proxy shared variants between the ethnic groups. The genome-wide transethnic correlation of causal-variant effect sizes is 0.898 and 0.851 for systolic and diastolic blood pressure, respectively. Some of the ancestry-specific association signals were also influenced by a selective sweep. Our results provide new evidence for the role of common ancestry-specific variants and natural selection in the occurrence of ethnic differences in complex traits such as blood pressure.

  Study EGAS00001002991

• Ductal keratin 15+ luminal progenitors in normal breast exhibit a basal-like breast cancer transcriptomic signature

  Normal breast luminal epithelial progenitors have been implicated as cell of origin in basal-like breast cancer, but their anatomical localization remains understudied. Here, we combine micro-collection of uncultured organoids and single cell mRNA sequencing (scRNA-seq) of FACS-sorted luminal epithelial cells with multicolor imaging to profile ducts and terminal ductal lobular units (TDLUs) and compare them with breast cancer subtypes. Unsupervised clustering reveals eleven distinct clusters and a differentiation trajectory starting with keratin 15+ (K15+) progenitors enriched in ducts. Spatial mapping of luminal progenitors is confirmed at the protein level by staining with critical duct markers. Comparison of the gene expression profiles of normal luminal cells with those of breast cancer subtypes reveals a strong correlation between normal breast K15+ ductal progenitors and basal-like breast cancer. We propose that K15+ basal-like breast cancers originate in ductal progenitors, which emphasizes the importance of not only lineages but also cellular position within the ductal-lobular tree.

  Study EGAS00001005963

• Enhanced cortical neural stem cell identity through SMAD/WNT inhibition in human cerebral organoids facilitates emergence of outer radial glial cells

  Cerebral organoids exhibit broad regional heterogeneity accompanied by limited cortical cellular diversity despite the tremendous upsurge in derivation methods, suggesting inadequate patterning of early neural stem cells (NSCs). Here we show that a short and early dual-SMAD/WNT inhibition course is necessary and sufficient for establishing robust and lasting cortical organoid NSC identity, efficiently suppressing of non-cortical NSC fates, while other widely used methods are inconsistent in their cortical NSC specification capacity. Accordingly, this method selectively enriches for outer radial glia (oRG) NSCs, which cytoarchitecturally demarcate well-defined outer sub-ventricular (oSVZ)-like regions propagating from superiorly radially organized, apical cortical rosette NSCs. Finally, this method culminates in the emergence of molecularly distinct deep and upper cortical layer neurons, and reliably uncovers cortex-specific microcephaly defects. Thus, a short SMAD/WNT inhibition is critical for establishing a rich cortical cell repertoire that enables mirroring fundamental molecular and cytoarchitectural features of cortical development and meaningful disease modeling.

  Study EGAS00001006063

• The immunopeptidome landscape associated with T cell infiltration, inflammation and immune-editing in lung cancer

  One key barrier for improving efficacy of cancer immunotherapy remains patient stratification. While patients with CD3+CD8+ T cell inflamed ‘hot’ tumors typically show better response to immune checkpoint inhibitors, it is still unknown if the repertoire of HLA bound peptides (HLAp) presented in ‘hot’ and ‘cold’ tumors is substantially different. We surveyed 61 tumor regions and adjacent non-malignant lung tissues from eight lung cancer patients and performed deep antigen discovery combining immunopeptidomics, genomics, bulk and spatial transcriptomics and explored the heterogenic expression and presentation of tumor (neo)antigens. We associated diverse immune cell populations with the immunopeptidome in CD3+CD8+ T cell excluded, infiltrated, hot and cold tumors and found evidence for lack of immune-editing and higher presentation efficiency of tumor antigens in cold and CD3+CD8+ T cell excluded tumors. This could have implications for the choice of combination therapies tailored to the patient’s mutanome and microenvironment.

  Study EGAS00001006298

• Combined gene expression and digital pathology identifies molecular mediators of T cell exclusion and immune suppression in ovarian cancer

  Close proximity between cytotoxic T lymphocytes and tumour cells is required for effective immunotherapy. However, what determines the spatial distribution of T cells in the tumour microenvironment is not well understood. Coupling digital pathology and transcriptome analysis on a large ovarian tumour cohort, we develop a machine learning approach to molecularly classify and characterize tumour-immune phenotypes. Our study identifies two important hallmarks characterizing T cell excluded tumours: 1) loss of antigen presentation on tumour cells and 2) upregulation of TGFb and activated stroma. Furthermore, we identify TGFb as a key mediator of T cell exclusion. TGFb reduces MHC-I expression in ovarian cancer cells in vitro; TGFb also activates fibroblasts and induced extracellular matrix (ECM) production as a potential physical barrier to hinder T cell infiltration. Our findings indicate that targeting TGFb may represent a promising strategy to overcome T cell exclusion and improve clinical benefits of cancer immunotherapy.

  Study EGAS00001003487

• Malignant progression of an ancestral bone marrow clone harboring a CIC-NUTM2A fusion in isolated myeloid sarcoma

  Myeloid sarcoma is a rare condition consisting of extramedullary myeloid blasts found in association with acute myeloid leukemia (AML) or, in the absence of bone marrow involvement. We identified an infant with isolated myeloid sarcoma whose bone marrow was negative for involvement by flow cytometry. Sequencing revealed the fusion oncogene CIC-NUTM2A and identified the sarcoma to be clonally evolved from the bone marrow which carried the fusion despite the absence of pathology. Murine modeling confirmed the ability of the fusion to transform hematopoietic cells and identified receptor tyrosine kinase signaling activation consistent with disruption of the CIC transcriptional repressor. These findings extend the definition of CIC-rearranged malignancies to include hematologic disease, provide insight into the mechanism of oncogenesis, and demonstrate the importance of molecular analysis and tracking of bone marrow involvement over the course of treatment in myeloid sarcoma, including patients that lack flow cytometric evidence of leukemia at diagnosis.

  Study EGAS00001006833

• Study of complex rearrangements and mutational signatures in neuroblastoma heterogeneous risk groups.

  Neuroblastoma is a pediatric solid tumor characterized by strong clinical heterogeneity. Although certain complex genomic alterations, such as extrachromosomal DNA amplifications (ecDNA), are associated with adverse outcome and have been recurrently detected in neuroblastomas, the mutational processes involved in their generation remain largely unclear. By examining the topography of complex rearrangements along with mutational signatures derived from all variant classes, we identify previously unrecognized co-occurring mutational footprints, which we termed mutational scenarios. We demonstrate that clinical neuroblastoma heterogeneity is linked to differences in the processes driving these mutational scenarios. Whereas high-risk MYCN-amplified neuroblastoma genomes were characterized by signs of replication slippage and stress, homologous recombination-associated signatures defined high-risk non-MYCN-amplified patients. Non-high-risk neuroblastomas, on the other hand, were marked by footprints of chromosome missegregation and TOP1 mutational activity. This analysis provides a systematic perspective on the repertoire of mutational patterns that contribute to clinical neuroblastoma heterogeneity.

  Study EGAS00001006983

• Natural history of clonal haematopoiesis (2017-09-04)

  The incidence of acute myeloid leukemia (AML) increases with age and mortality exceeds 90% when diagnosed after age 60. Only 10-15% of cases evolve from a pre-existing myeloproliferative or myelodysplastic disorder; the remaining cases arise de novo without a detectable prodrome and are diagnosed upon development of bone marrow failure. Analysis of diagnostic blood samples has demonstrated that de novo AML is preceded by the accumulation of somatic mutations in pre-leukemic hematopoietic stem and progenitor cells (preL-HSPCs) that subsequently undergo clonal expansion. If individuals in this pre-leukemic phase could be identified, methods for determination of risk and monitoring for progression to overt AML could be developed. However recurrent AML mutations also accumulate during aging in healthy individuals who never develop AML, referred to as age related clonal hematopoiesis (ARCH). To distinguish individuals with preL-HSPCs at high risk of developing AML from those with ARCH, we undertook deep targeted sequencing of genes recurrently mutated in AML in blood samples from 133 individuals in the European Prospective Investigation into Cancer and Nutrition (EPIC) study taken on average 6 years before they developed AML (pre-AML group), together with 683 matched healthy individuals (Control group). Pre-AML cases displayed accelerated age-correlated accumulation of somatic mutations.The identity, number and variant allele frequency (VAF) of mutations differed between the two groups, and were incorporated into a computational model of AML risk prediction that accurately distinguished pre-AML cases from controls on average 7 years prior to AML development. Our findings provide proof of concept that early prediction of AML development is feasible in high-risk populations, paving the way for early disease detection, monitoring, and potentially prevention.

  Dataset EGAD00001003703

• Constitutional and somatic genomic rearrangements coherently restructure chromosome 21 in acute lymphoblastic leukaemia

  Changes in gene dosage are a major driver of cancer1, engineered from a finite, but increasingly well annotated, repertoire of mutational mechanisms2-6. These processes operate over levels ranging from individual exons to whole chromosomes, often generating correlated copy number alterations across hundreds of linked genes. An example of the latter is the 2% of childhood acute lymphoblastic leukemia (ALL) characterized by recurrent intrachromosomal amplification of megabase regions of chromosome 21 (iAMP21)7,8 To dissect the interplay between mutational processes and selection on this scale, we used genomic, cytogenetic and transcriptional analysis, coupled with novel bioinformatic approaches, to reconstruct the evolution of iAMP21 ALL. We find that individuals born with the rare constitutional Robertsonian translocation between chromosomes 15 and 21, rob(15;21)(q10;q10)c, have ~2700-fold increased risk of developing iAMP21 ALL compared to the general population. In such cases, amplification is initiated by chromothripsis involving both sister chromatids of the dicentric Robertsonian chromosome. In contrast, sporadic iAMP21 is typically initiated by breakage-fusion-bridge (BFB) events, often followed by chromothripsis or other rearrangements. In both sporadic and iAMP21 in rob(15;21)c individuals, the final stages of amplification frequently involve large-scale duplications of the abnormal chromosome. The end-product is a derivative chromosome 21 or a derivative originating from the rob(15;21)c chromosome, der(15;21), respectively, with gene dosage optimised for leukemic potential, showing constrained copy number levels over multiple linked genes. In summary, the constitutional translocation, rob(15;21)c, predisposes to leukemia through a novel mechanism, namely a propensity to undergo chromothripsis, likely related to its dicentric nature. More generally, our data illustrate that several cancer-specific mutational processes, applied sequentially, can co-ordinate to fashion copy number profiles over large genomic scales, incrementally refining the fitness benefits of aggregated gene dosage changes.

  Dataset EGAD00001000658

• Evolving epigenomics of immune cells in type 1 diabetes at single nuclei resolution

  The appearance of diabetes-associated autoantibodies is the first detectable sign of the disease process leading to type 1 diabetes (T1D). Evidence suggests that T1D is a heterogenous disease, where the type of antibodies first formed imply subtypes. Here, we followed 49 children, who subsequently presented with T1D and 49 matched controls, profiling single-cell epigenomics at different time points of disease development. Quantitation of cell and nuclei populations as well as transcriptome and open-chromatin states indicated robust, early, replicable monocyte lineage differences between cases and controls, suggesting heightened pro-inflammatory cytokine secretion early among cases. The order of autoantibody emergence in cases showed variation across lymphoid and myeloid cells, potentially indicating cellular immune response divergence. The strong monocytic lineage representation in peripheral blood immune cells before seroconversion and the weaker differential coordination of these gene networks close to clinical diagnosis emphasizes the importance of early life as a critical phase in T1D development.

  Study EGAS50000000863

• Sensitive and Frequent Identification of High Avidity Neo-epitope Specific CD8 + T-cells in Immunotherapy-naïve Ovarian Cancer

  Immunotherapy directed against private tumor neo-antigens derived from non-synonymous somatic mutations is a promising strategy of personalized cancer immunotherapy. However, feasibility in low mutational load tumor types remains unknown. Comprehensive and deep analysis of circulating and tumor-infiltrating lymphocytes (TILs) for neo-epitope specific CD8 + T cells allowed prompt identification of oligoclonal and polyfunctional such cells from most immunotherapy-naïve patients with advanced epithelial ovarian cancer studied. Neo-epitope recognition was discordant between circulating T cells and TILs, and was more likely to be found among TILs, which displayed higher functionalavidity and unique TCRs with higher predicted affinity than their blood counterparts. Our results imply that identification of neo-epitope specific CD8 + T cells is achievable even in tumors with relatively low number of somatic mutations, and neo-epitope validation in TILs extends opportunities for mutanome-based personalized immunotherapies to such tumors.

  Study EGAS00001002803