Search Results - EGA European Genome-Phenome Archive

Exome-sequencing identifies new oncogenes and tumor suppressor genes recurrently altered in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is the most common primary liver malignancy. High-resolution copy number analysis of 125 tumors of which 24 were subjected to whole-exome sequencing identified 135 homozygous deletions and 994 somatic gene mutations with predicted functional consequences. We identified new recurrent alterations in 4 genes (ARID1A, RPS6KA3, NFE2L2 and IRF2) not previously described in HCC. Functional analyses demonstrated tumor suppressor properties for IRF2 whose inactivation, exclusively found in hepatitis B virus related tumors, leads to impaired TP53 function. Alternatively, inactivation of proteins involved in chromatin remodeling was frequent and predominant in alcohol related tumors. Moreover, activation of the oxidative stress metabolism and inactivation of RPS6KA3 were new pathways associated with WNT/beta-catenin activation, thereby suggesting a cooperative effect in tumorigenesis. This study shows the dramatic somatic genetic diversity in HCC, it reveals interactions between oncogene and tumor suppressor gene mutations markedly related to specific risk factors.

Study EGAS00001000217

Integrated genetic and epigenetic analysis defines novel molecular clusters in rhabdomyosarcoma

Rhabdomyosarcoma (RMS) is the most common soft tissue sarcoma in childhood. To unravel the genetic/epigenetic basis of RMS, we studied 60 RMS cases using whole exome/transcriptome sequencing, copy number (CN) profiling, and DNA methylome analysis. Based on DNA methylation patterns, RMS was clustered into 4 distinct subtypes, which exhibited remarkable correlation with mutation/CN profiles, histological phenotypes, and clinical behaviors. A1 and A2 subtypes, especially A1, largely corresponded to alveolar histology with frequent PAX3/7 fusions and alterations in cell cycle regulators. In contrast, mostly showing embryonal histology, both E1 and E2 subtypes were characterized by high frequency of CN alterations and/or allelic imbalances, FGFR4/RAS/AKT pathway mutations and PTEN mutations/methylation and in E2, also by p53 inactivation. Despite generally poor prognosis in RMS, patients in E1 cluster exceptionally showed excellent prognosis. Our results highlight the close relationship between DNA methylation status and gene mutations and biological behavior in RMS.

Study EGAS00001000884

DIME study: Safety, dose-response and efficacy of treatment with Anaerobutyricum soehgenii on glucose metabolism in human subjects with metabolic syndrome

The intestinal microbiota has been implicated in insulin resistance, although evidence regarding causality in humans is scarce. We herefore performed a phase I/II dose-finding and safety study on the effect of oral intake of the anaerobic butyrogenic Anaerobutyricum soehgenii on glucose metabolism in subjects with metabolic syndrome. We found that treatment with A. soehgenii was safe and observed an overall significant and dose-dependent increase in insulin sensitivity after 4 weeks in all treated subjects. This was accompanied by an altered microbiota composition and a change in bile acid metabolism. Finally, we show that metabolic response upon administration of A. soehgenii (defined as improved insulin sensitivity 4 weeks after A. soehgenii intake) is dependent on microbiota composition at baseline. These data in humans are promising and additional studies are needed to study long-term effects as well as modes of delivery.

Study EGAS00001003498

Mutations in the RAS/MAPK pathway drive replication repair deficient hypermutated tumors and confer sensitivity to MEK inhibition

The RAS/MAPK pathway is an emerging targeted pathway across a spectrum of both adult and pediatric cancers. Typically, this is associated with a single, well-characterized point mutation in an oncogene. Hypermutant tumors which harbor many somatic mutations may obscure the interpretation of such targetable genomic events. We find that replication repair deficient (RRD) cancers which are universally hypermutant and affect children born with RRD cancer predisposition, are enriched for RAS/MAPK mutations (p=10-8). These mutations are not random, exist in subclones, and increase in allelic frequency over time. The RAS/MAPK pathway is activated both transcriptionally and at the protein level in patient derived RRD tumors and these tumors responded to MEK inhibition in vitro and in vivo. Treatment of patients with RAS/MAPK hypermutant gliomas reveal durable responses to MEK inhibition. Our observations suggest that hypermutant tumors may be addicted to oncogenic pathways resulting in favorable response to targeted therapies.

Study EGAS00001005008

Oncogenic cooperation in a human de novo T-ALL model

We previously modelled T-cell acute lymphoblastic leukemia (T-ALL) by over-expressing four oncogenes (activated NOTCH1, LMO2, TAL1, and BMI1) in healthy human umbilical cord blood cells through lentiviral transduction (Kusakabe et al, Nat Commun 10, 2913 (2019). https://doi.org/10.1038/s41467-019-10510-8). We have now tested individual effects of the four oncogenes by transducing human cells with all possible combinations of one, two, three, and four oncogenes. We also tested the effects of additional known T-ALL oncogenes including HOXA9, LYL1, MEF2C, NXK2.1, TLX1, and TLX3. In addition to culture in vitro on OP9-DL1 feeders, we also injected transduced cells into immunodeficient NSG mice. We observed differing abilities of the various oncogene combinations to support growth in vitro and frank leukemia in vivo. This study includes RNA-seq data from samples of transduced cells cultured in vitro as well as cells harvested from clinically moribund mice after development of leukemia in vivo.

Study EGAS00001006055

Resolving the immune landscape of human prostate at a single cell level in health and cancer

The prostate gland produces prostatic fluid, high in zinc and citrate and essential for the maintenance of spermatozoa. Prostate cancer is a common condition with limited treatment efficacy in castration-resistant metastatic disease, including with immune checkpoint inhibitors. We used single-cell RNA-sequencing to perform an unbiased assessment of the cellular landscape of human prostate and identified a previously unappreciated subset of tumour-enriched androgen receptor-negative luminal epithelial cells, with increased expression of cancer-associated genes. We also found a variety of innate and adaptive immune cells in normal prostate that were transcriptionally perturbed in prostate cancer. An exception was a unique, prostate-specific, zinc transporter-expressing macrophage population (MAC-MT), that contributed to tissue zinc accumulation in homeostasis, but showed enhanced inflammatory gene expression in tumours, including T cell-recruiting chemokines. Remarkably, enrichment of the MAC-MT signature in cancer biopsies was associated with improved disease-free survival, suggesting beneficial anti-tumour functions.

Study EGAS00001005787

Tracking early lung cancer metastatic dissemination in TRACERx using ctDNA

These data relate to Abbosh et al 2023 'Tracking early lung cancer metastatic dissemination in TRACERx using ctDNA'. Some patients were included in this work that were excluded from the other TRACERx 421 papers (Frankell et al and Al-bakir et al) often due to exclusion criteria in the TRACERx clinical trial. Reasons include partial contamination with C>A artefact mutational signature (CRUK0480 ,0490) which were included for ctDNA detection analyses using high confidence clonal mutations but not clonality analyses, incomplete resection at primary surgery (CRUK0291, 0234, 0230, 0387, 0622) and a concurrent oesophageal second primary cancer (CRUK0498). The primary tissue exome sequencing for these patients that were used in this study are included in this repository. Deep targeted sequencing of (median 200) tumour specific mutations in plasma for 1069 samples from 198 TRACERx patients are also included. Additional details related to these patients and samples can be found in the supplementary or data repositories from Frankell et al and Abbosh et al.

Study EGAS00001006923

MINCR is a MYC-induced lncRNA able to modulate MYC’s transcriptional network in Burkitt lymphoma cells

Despite the established role of the transcription factor MYC in cancer, little is known about the impact of a new class of transcriptional regulators, the long non-coding RNAs (lncRNAs), on the way MYC is able to influence cellular transcriptome. To this aim we have intersected RNA-sequencing data from two MYC-inducible cell lines and from a cohort of 91 mature B-cell lymphomas carrying, or not carrying, genetic variants resulting in MYC over-expression. By this approach, we identified 13 lncRNAs differentially expressed in IG-MYC-positive Burkitt lymphoma and regulated in the same direction by MYC in the model cell lines. Among them we focused on a lncRNA that we named MINCR, for MYC-Induced long Non-Coding RNA, showing a strong correlation with MYC expression in MYC-positive lymphomas and also in pancreatic ductal adenocarcinomas. To understand its cellular role we performed RNA interference (RNAi) experiments and found that MINCR knock-down is associated with a reduction in cellular viability, due to an impairment in cell cycle progression. Differential gene expression analysis following RNAi showed a strongly significant enrichment of cell cycle genes among the genes down-regulate following MINCR knock-down. Interestingly these genes are enriched in MYC binding sites in their promoters, suggesting that MINCR acts as a modulator of MYC transcriptional program. Accordingly, following MINCR knock-down, we observed a reduction in the binding of MYC to the promoters of selected cell cycle genes. Finally we provide evidences that down-regulation of AURKA, AURKB and CTD1 may explain the reduction in cellular proliferation observed upon MINCR knock-down. We therefore suggest that MINCR is a newly identified player in the MYC transcriptional network able to control the expression of cell cycle genes.

Dataset EGAD00001001441

Mutational Mechanisms in Multiply Relapsed Pediatric Acute Lymphoblastic Leukemia

Pediatric acute lymphoblastic leukemia (ALL) is marked by low mutational load at initial diagnosis, which increases at relapse. To determine which processes are active in (relapsed) ALL and how they behave during disease progression before and after therapy, we performed whole genome sequencing on tumor samples of 29 multiply relapsed ALL patients. Mutational load increased upon relapse in 28 patients and every subsequent relapse in 22 patients, with UV-like damage, APOBEC activity, reactive oxygen species, thiopurine-associated damage and an unknown therapy component driving mutagenesis. Thiopurines were the most prominent source of new mutations in relapse, affecting over half of the studied patients and causing potential relapse-driving mutations in multiple patients. Mutational processes often affected patients over longer time periods, but could also occur in isolated events, suggesting the requirement of additional triggers. Our data pose mutational processes as prominent secondary drivers with an important role in ALL development and progression.

Study EGAS00001007900

SMARCB1 loss activates patient-specific distal oncogenic enhancers in malignant rhabdoid tumors

Malignant rhabdoid tumor (MRT) is a highly malignant and often lethal childhood cancer. MRTs are genetically defined by bi-allelic inactivating mutations in SMARCB1, a member of the BRG1/BRM-associated factors (BAF) chromatin remodeling complex. Mutations in BAF complex members are common in human cancer, yet their contribution to tumorigenesis remains in many cases poorly understood. Here, we studied derailed regulatory landscapes as a consequence of SMARCB1 loss in the context of MRT. Our multi-omics approach on patient-derived MRT organoids revealed a dramatic reshaping of the regulatory landscape upon SMARCB1 reconstitution. Chromosome conformation capture experiments subsequently revealed patient-specific looping of distal enhancer regions with the promoter of the MYC oncogene. This intertumoral heterogeneity in MYC enhancer utilization is also present in patient MRT tissues as shown by combined single-cell RNA-seq and ATAC-seq. We show that loss of SMARCB1 drives patient-specific epigenetic reprogramming underlying MRT tumorigenesis.

Study EGAS00001007590

PD-1 Instructs a Tumor Suppressive Metabolic Program to Restrain AP-1 Activity in T Cell Lymphoma

T cell non-Hodgkin lymphomas (T-NHLs) represent a heterogeneous group of aggressive cancers of mature CD4+ T cells, for which therapeutic options are limited. Recent work uncovered that the PDCD1 encoded immune checkpoint receptor PD-1 is a key tumor suppressor in T cells. PD-1 is recurrently inactivated in T-NHL and the highest frequencies of PDCD1 deletions are detected in advanced disease, predicting worse prognosis. The tumor-suppressive mechanisms of PD-1 signaling remain unknown. In the present study, we identify transcriptional and epigenetic mechanisms underlying PD-1 tumor suppression in T-NHL.Some subjects included in this study overlap with the subjects from phs002456. To establish the link between the overlapping subjects, the Subject Consent datasets will be utilized.

Study phs003312

Next Generation Sequencing of Stage IV Squamous Cell Lung Cancers Reveals an Association of PI3K Aberrations and Evidence of Clonal Heterogeneity in Patients with Brain Metastases

Putative oncogenic pathways in squamous cell lung cancer have been recently characterized, although their biologic repercussions in patients is largely unknown. This study sought to discover potential clinical manifestations of major pathways in squamous cell lung cancer, particularly the PI3K pathway. Two key findings emerged: patients with stage IV squamous cell lung cancer whose tumors harbored upstream PI3K aberrations had significantly worse survival and a higher burden of metastatic disease. In addition, brain metastases were significantly more common in these patients than in others. Paired lung primary/brain metastasis genotyping, including RNA sequencing and whole exome sequencing, uncovered a high degree of genetic heterogeneity between lung/brain pairs, and identified potential regulators of the metastatic process to brain.

Study phs000907

GWAS for atrial fibrillation in the Japanese population

We performed a genome-wide association study (GWAS) that utilized 8,180 atrial fibrillation cases and 28,612 controls and followed up in an additional 3,120 cases and 125,064 controls in the Japanese population. We replicated previously reported loci and identified six novel loci. Five of the six novel loci were specifically associated with atrial fibrillation in the Japanese population after comparing our data to individuals of European ancestry, suggesting there might be different susceptibility genetic factors across ancestries. Our study has discovered variants in genes HAND2, KCND3 and NEBL that are relevant to atrial fibrillation susceptibility. The involvement of PPFIA4 and SH3PXD2A in axon guidance also suggested its role in the disease pathogenesis. Our findings may contribute to a better understanding of atrial fibrillation susceptibility and pathogenesis.

Study JGAS000101

Genome-wide expression profiles to compare array-based, RNAseq and NanoString technologies in patients with resected pancreatic ductal carcinoma.

Using formalin-fixed paraffin embedded (FFPE) tissues collected prospectively in patients with resected pancreatic ductal carcinoma (PDC) we generated genome-wide expression profiles to compare array-based, RNAseq and NanoString technologies. Samples included in the study were collected 17 patients. After careful selection by the pathologist of 17 malignant cells-enriched, 7 stroma-enriched, and 6 normal (normal pancreas in 4 cases and normal duodenum in 2 cases) regions, sections were macrodissected, and total RNA extracted. Two additional FFPE-frozen matched-paired PDAC from our local Biobank were included. Our study represents the most extensive work comparing three technologies to generate gene expression profiles from FFPE samples, and provides technical guidance for future biomarker studies in samples collected prospectively in the context of clinical trials.

Study EGAS00001002501

Non-Mendalian inheritance of extrachromosal DNA elements can drive disease evolution in glioblastoma

Genomic heterogeneity of glioblastoma (GBM) is suspected to contribute to the poor response to therapy of this disease. We compared molecular characteristics between primary GBM, neurospheres and orthotopic xenograft models derived from the same parental tumor. Driver alterations were in majority propagated from tumor to model systems. Extrachromosomal amplifications of MET, a proto-oncogene coding for a receptor tyrosine kinase, were detected in three primary GBM, largely discarded in neurospheres cultures, but resurfaced in xenografts. The clonal dynamics inferred by somatic single nucleotide variants (sSNVs) in MET-amplified samples diverged from the pattern delineated by the MET amplification event suggesting that the MET event and sSNVs were inherited in different manners. Our analysis shows that extrachromosomal elements are able to drive tumor progression.

Study EGAS00001001878

High-resolution structural genomics reveals new therapeutic vulnerabilities in glioblastoma

We investigated the role of 3D genome architecture in instructing functional properties of glioblastoma stem cells (GSCs) by generating the highest-resolution 3D genome maps to-date for this cancer. Integration of DNA contact maps with chromatin and transcriptional profiles identified specific mechanisms of gene regulation, including individual physical interactions between regulatory regions and their target genes. Residing in structurally conserved regions in GSCs was CD276, a gene known to play a role in immuno-modulation. We show that, unexpectedly, CD276 is part of a stemness network in GSCs and can be targeted with an antibody-drug conjugate to curb self-renewal, a key stemness property. Our results demonstrate that integrated structural genomics datasets can be employed to rationally identify therapeutic vulnerabilities in self-renewing cells.

Study EGAS00001003493

Recurrent Somatic Mutations of PTPN1 in Primary Mediastinal B cell lymphoma and Hodgkin Lymphoma

Hodgkin lymphoma (HL) and primary mediastinal B cell lymphoma (PMBCL) are related lymphomas sharing pathological, molecular and clinical characteristics. Here, we discovered recurrent somatic coding sequence mutations of the tyrosine phosphatase gene PTPN1 in the tumor genomes and transcriptomes of these B cell lymphomas (6 of 30 or in 20% of HL cases and 13 of 49 or in 27% of PMBCL cases), consisting of nonsense, missense and frameshift mutations. We demonstrate that PTPN1 mutations lead to reduced phosphatase activity and increased phosphorylation of JAK-STAT pathway members. Moreover, silencing of PTPN1 by RNA interference in HL cell line KM-H2 resulted in hyperphosphorylation and overexpression of downstream oncogenic targets. Our data establish PTPN1 mutations as novel drivers in B cell lymphomagenesis.

Study EGAS00001000554

Germline variant analysis in childhood AML

Analysis of rare germline variants in childhood AML in a large panel of cancer predisposition genes (n=216) compiled from literature review, and including genes involved in familial hematological malignancies (HM) and bone marrow failure (BMF) syndromes. The prevalence of extremely rare variants in the combined childhood AML cohort (n=72) was compared to that in the Medical Genome Reference Bank (MGRB; n=2570) comprising individuals aged at least 70 years with no history of cardiovascular disease, dementia or cancer. This showed a significant increase of rare alleles in childhood AML for 100% of subset comparisons. Next additional stringent filtering was applied to determine predicted damaging germline predisposition variants. Overall, 21% of the Australian cohort and 25% of the TARGET cohort presented germline variants predicted to be damaging predisposition variants.

Study EGAS00001006276

Gene Expression in an African American Schizophrenia Dataset

Schizophrenia is a common and severe psychotic disorder. While some common SNPs and rare copy number variants have been identified as being significantly associated with disease risk, the biological mechanisms remain largely undefined. To identify gene expression abnormalities in schizophrenia, we generated whole-genome gene expression profiles using RNAseq on lymphoblastoid cell lines from schizophrenia cases and controls of African American ancestry. Genes related to immune processes were enriched in the genes differentially expressed in the schizophrenia cases. Approximately half of the differentially expressed genes in this African American dataset were also differentially expressed by affection status in our previously studied European ancestry dataset (PMID: 28418402).

Study phs002842

PAX4 loss of function increases diabetes risk by altering human pancreatic endocrine cell development

The coding variant (p.Arg192His) in the transcription factor PAX4 is associated with an altered risk for type 2 diabetes (T2D) in East Asian populations. In mice, Pax4 is essential for beta cell formation but its role on human beta cell development and/or function is unknown. Participants carrying the PAX4 p.His192 allele exhibited decreased pancreatic beta cell function compared to homozygotes for the p.192Arg allele in a cross-sectional study in which we carried out an intravenous glucose tolerance test and an oral glucose tolerance test. In a pedigree of a patient with young onset diabetes, several members carry a newly identified p.Tyr186X allele. In the human beta cell model, EndoC-βH1, PAX4 knockdown led to impaired insulin secretion, reduced total insulin content, and altered hormone gene expression. Deletion of PAX4 in human induced pluripotent stem cell (hiPSC)-derived islet-like cells resulted in derepression of alpha cell gene expression. In vitro differentiation of hiPSCs carrying PAX4 p.His192 and p.X186 risk alleles exhibited increased polyhormonal endocrine cell formation and reduced insulin content that can be reversed with gene correction. Together, we demonstrate the role of PAX4 in human endocrine cell development, beta cell function, and its contribution to T2D-risk.

Dataset EGAD50000000516

Single-cell spatiotranscriptomic dissection of ex vivo human heart right atrial appendage and pericardial fluid in ischemic heart disease and heart failure

We use cardiac and pericardial fluid biopsies collected during open-heart surgery in control, ischemic heart disease, heart failure, and myocardial infarction context. For each sample, single-nuclei RNA sequencing experiment is performed. We also perform spatial transcriptomics on the heart samples. We annotate the cells in major cell types, in addition to subtypes annotation of vascular and immune cells. The disease annotation enables us to reveal substantial differences in gene expression at the cell subpopulation levels. Our results demonstrate the importance of high-resolution cellular type/state mapping in the elucidation of human cardiovascular disease pathogenesis.

Study EGAS50000000653

Combination Therapies for Personalised Cancer Medicine in drug resistant EGFR mutant lung cancer

This study involves mutagenizing a range of different cell lines with ENU to identify those mutations which engender resistance to targeted treatment. In the last decade we have begun to move towards the use of targeted therapeutics in the clinic, often resulting in dramatic response rates in cancer patients. However, clinical experience has demonstrated time and time again that such responses are invariably followed by the development of drug resistance. Identification of the underlying mechanisms may enable us to reverse such resistance. Traditional methods of modelling this resistance in vitro can lead to a plethora of potential resistance mechanisms that can be difficult to decipher.

Study EGAS00001002509

Combination Therapies for Personalised Cancer Medicine in 11-18

This study involves mutagenizing 11-18 with ENU to identify those mutations which engender resistance to targeted treatment. In the last decade we have begun to move towards the use of targeted therapeutics in the clinic, often resulting in dramatic response rates in cancer patients. However, clinical experience has demonstrated time and time again that such responses are invariably followed by the development of drug resistance. Identification of the underlying mechanisms may enable us to reverse such resistance. Traditional methods of modelling this resistance in vitro can lead to a plethora of potential resistance mechanisms that can be difficult to decipher.

Study EGAS00001002579

Overrepresentation of genetic variation in the AnkyrinG interactome is related to a range of neurological disorders

Upon the discovery of numerous genes involved in the pathogenesis of neurodevelopmental disorders, several studies showed that a significant proportion of these genes converge on common pathways and protein networks. Here, we used a reversed approach, by screening the well-characterized AnkyrinG protein-protein interaction network, implicated in a variety of neurodevelopmental disorders, for genetic variation in a large cohort of 1009 cases with neurodevelopmental disorder. We identified a significant enrichment of de novo potentially disease-causing variants in this network, confirming that this protein network plays an important role in the emergence of several neurodevelopmental disorders.

Study EGAS00001004326

CRISPR/Cas9-mediated genome editing of Schistosoma mansoni acetylcholinesterase

Here we report successful gene knock-in (KI) in the eggs of Schistosoma mansoni by combining CRISPR/Cas9 with single-stranded oligodeoxynucleotides (ssODNs). We targeted the acetylcholinesterase (AChE) gene of S. mansoni using two synthetic guide RNAs (gRNAs), X5 and X7, respectively. Liver eggs of S. mansoni were exposed to CRISPR-vector containing X5 or X7 by electroporation. Simultaneously, eggs were transfected with a ssODN donor encoding a stop codon in all six frames. Next generation sequencing analysis revealed that CRISPR/Cas9-mediated editing in S. mansoni eggs resulted in Homology-Directed Repair (HDR) when template DNA ssODN provided. Furthermore, soluble egg antigen (SEA) from AChE-modified eggs exhibited markedly reduced AChE activity compared with controls, indicative that programmed Cas9 cleavage mutated the AChE gene. Following injection of modified schistosome eggs into the tail veins of mice, a significant decrease in granuloma size in the lungs of these animals. Notably, an enhanced Th2 response induced by eggs in lung, and splenocytes small intestine-draining mesenteric lymph node cells was also generated in mice injected with X5-KI eggs in different methods. These findings further demonstrate the power and utility of CRISPR/Cas9-based genome editing for undertaking functional genomics studies in schistosomes.

Dataset EGAD00001006573

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