14372 results for ""Pennsylvania+German"+ACS+study+'Socius'+open+access"

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• Defined Lifestyle and Germline Factors Predispose Asian Populations to Gastric Cancer

  Gastric cancer (GC) is one of the leading causes of cancer mortality throughout the world, with the highest incidence in east-Asia. Although the somatic genetics of GC has extensively been characterized by recent advances in cancer genome sequencing, the germline and environmental effects on GC and their ethnic differences have poorly been understood. Here, we performed genomic scale trans-ethnic analysis of 531 GC cases (319 Asian and 212 non-Asians), by integrating east-Asian and public GC datasets. There is one distinct GC subclass with clear alcohol-associated mutation signature and strong Asian specificity, and almost all the cases in the subclass are attributable to alcohol intake behavior, smoking habit, and Asian-specific ALDH2 defective allele. Alcohol-related GCs have low mutation burden and a characteristic immune profile of increased B-cell infiltration into the tumor area in relation to cancer cell-intrinsic CXCL13 chemokine expression. In addition to germline variants of genes involved in BRCA pathways, we found frequent (7.4%) germline CDH1 variants among Japanese GCs. Most of them were attributed to a few recurrent SNVs shared by both Japanese and Koreans, suggesting the existence of common ancestral events and widespread distributions of these pathogenic variants among east-Asian populations. Specifically, approximately one-fifth of diffuse-type GCs were attributable to the combination of alcohol intake and defective-ALDH2 allele or to germline CDH1 variants. These results revealed uncharacterized impacts of germline variants and their interplays with lifestyles in the high incidence areas.

  Study JGAS000228

• Analysis of mutational and proteomic heterogeneity of gastric cancer to monitor post-treatment tumor burden using circulating tumor DNA

  It remains unclear whether complete spectrum of tumor heterogeneity is reflected in circulating tumor DNA (ctDNA). Here, we performed multi-regional target sequencing of primary tumors from 10 patients who underwent surgical resection for gastric cancer. A total of 126 non-synonymous mutations were identified from 30 samples from 10 tumors. Of these, 16 (12.7%) were likely mutations that occurred early in tumor development (i.e., present in all three regions) and were designated founder mutations. Among those validated with highly sensitive digital PCR (dPCR), 93% of non-founder mutations were found in all three regions. Variant allele frequencies (VAFs) of founder mutations were significantly higher than those of non-founder mutations. Phylogenetic analysis demonstrated that five of eight tumors (62.5%, excluding two hypermutator) had at least one identifiable truncal/founder mutation. These findings led us to prioritize founder mutations for ctDNA detection with individually-designed primer/probe sets for dPCR. Marked proteomic diversity was present across the tumor regions both within and between patients independent of mutational status. In preoperative plasma, the average ctDNA VAF of founder mutations was significantly higher than that of non-founder mutations (p = 0.039). Our present data demonstrated that high VAF mutations in the tumor likely represent founder or truncal mutations. However, mutation patterns alone appear insufficient to predict protein heterogeneity. These results suggest that, in practice, mutations having high VAF identified without multi-regional sequencing may be useful for ctDNA monitoring but are inadequate to fully predict proteomic heterogeneity of the tumor.

  Study JGAS000231

• Innate myeloid cell sbuset-specific gene expression patterns in the human colon are altered in Crohn's disease patients

  Background: There is a heterogeneous subset innate myeloid cells, such as macrophages and dendritic cells, in the human intestinal lamina propria. Several studies have demonstrated that these cells contribute to the maintenance of gut homeostasis through induction of inflammatory responses and tolerance via cell type-specific mechanisms; whereas, disrupted innate immune responses are implicated in the pathogenesis of Crohn?s disease. However, the detailed mechanisms by which each innate myeloid subset regulates gut homeostasis and inflammation largely remains unknown. Aim: We aimed to clarify the comprehensive gene expression profiles of innate myeloid cell subsets in the lamina propria from normal human colons (NC) and the inflamed colon sites from patients with Crohn?s disease (CDi). Methods: We performed RNA-sequencing analysis and precise bioinformatics analysis on three innate myeloid cell subsets, CD14-CD11c-, CD14-CD11c+, and CD14+CD11c+CD163low cells from NC and CDi. Results: Transcriptional analysis of the three subsets from the NC showed distinct gene expression patterns and gene ontology (GO) enrichment analysis revealed the associated innate myeloid subset-specific biological process (BP) terms. In addition, changes in gene expression patterns were observed in innate myeloid subsets from CDi. Furthermore, the core GO-BP terms for the genes upregulated in the innate myeloid cells from CDi were distinct from those found in NC. Conclusion: Our data identified the innate myeloid cell subset-specific transcriptomes and the associated enriched GO-BP terms in the NC and found these patterns were altered in CDi.

  Study JGAS000127

• DNA demethylation is associated with malignant progression of low-grade gliomas

  To elucidate the mechanisms of tumor progression is key to discovering strategies for treating patients with lower-grade glioma. Thus to characterize the changes in the molecular profile during malignant progression, we performed methylation array analysis (122 tumors), whole-exome sequencing (36 tumors and matched normal samples), and RNA sequencing (31 tumors). This cohort included 24 matched pairs of initial lower-grade gliomas and recurrent tumors, most of which showed malignant progression when they recurred. Nearly half of IDH-mutant glioblastomas that had progressed from lower-grade gliomas exhibited characteristic partial DNA demethylation in previously methylated genomic regions of their corresponding initial tumors, which had the glioma CpG island methylator phenotype (G-CIMP). In these glioblastomas, cell cycle-related genes were upregulated, RB and PI3K-AKT pathway genes were frequently altered. Notably, bioinformatics analysis revealed that late-replicating domain was significantly enriched in the demethylated regions that were mostly located in non-regulatory regions, suggesting that the loss of DNA methylation during malignant transformation may involve mainly passive demethylation due to a delay in maintenance of methylation during accelerated cell division. Nonetheless, a limited number of genes including IGF2BP3, which potentially drives cell proliferation, were presumed to be upregulated due to demethylation of their promoter. Thus, cell proliferation was further promoted by passive demethylation in the promoter region of these oncogenic genes. Our data indicated that demethylation of the G-CIMP profile found in a subset of recurrent gliomas reflects accelerated cell divisions accompanied by malignant transformation. Oncogenic genes activated by such epigenetic change represent potential therapeutic targets.

  Study JGAS000146

• Gene expression of human Th17 cells before and after activation

  Although gene expression of human Th17 clones has been studies, to date, molecular mechanisms for human Th17 development remain unclear. We have analyzed gene expression of human Th17 cells before and after activation. Th17-cell clones from peripheral blood CD4 T cells cultured with LPS-stimulated dendritic cells derived from monocytes stimulated by TNF were established by a limited dilution method. One of the Th17 clones was proliferated significantly, and high percentages (>70%) of Th17 cells in the cultured cells were maintained by addition of monocytes, IL-1b, and IL-15. CD161+CXCR3- cells (CD161+Th17) in the cultures were sorted and purified up to approximately 97% of IL-17-producing cells after treatment with PMA/ionomycin. Furthermore, these cells were treated with TCR-stimuli, IL-1b, and IL-23 for 2 days, and IL-17-producing Th17 cells (active-Th17) detected by IL-17-catch-up antibodies were sorted. Total RNA sampled from 1x 106 CD161+Th17, active-Th17, na?ve CD4 T cells, or CXCR3+ Th1 cells from combined CD4 T and dendritic cell cultures was used for SAGE. SAGE was performed by using SOLID TM SAGETM kit with barcoding adaptor molecules (Applied Biosystems). DNA sequence was analyzed by using AB5500 Genetic Analyzer (Applied Biosystems), and gene expression was analyzed by using SOLID? SAGETM software (Applied Biosystems). Our data shows high levels of IL-17A-mRNA expression by active-Th17; however, but only slight expression by CD161+Th17. Therefore, the data could provide alteration of gene expression by Th17 cells before and after stimulation.

  Study JGAS000005

• Identification of driver oncogenes in scirrhous-type gastric cancer cell lines

  Scirrhous type gastric cancer (SGC) is one of the most intractable cancer subtypes in human, and its therapeutic targets have been rarely identified to date. Exploration of somatic mutations in the SGC genome with the next generation sequencers has been hampered by low tumor contents by the markedly increased fibrous tissues. Thus, SGC cell lines may be useful resources to search for novel oncogenes in. Here we have conducted whole exome sequencing and RNA sequencing on two SGC cell lines, OCUM-8 and OCUM-9. Interestingly, most of the mutations thus identified have not been reported. In OCUM-8 cells, a novel CD44-IGF1R fusion gene is discovered, the protein product of which ligates the amino-terminus of CD44 to the transmembrane and the tyrosine-kinase domains of IGF1R. Further, both of CD44 and IGF1R are markedly amplified in the OCUM-8 genome and abundantly expressed. CD44-IGF1R has a transforming ability, and the suppression of its kinase activity leads to rapid cell death of OCUM-8. On the other hand, OCUM-9 seems to possess multiple oncogenic events in its genome. The MET gene is highly amplified, and the treatment of OCUM-9 with crizotinib, a MET inhibitor, results in cell death. Further, a novel BORCS5-ETV6 fusion gene is identified in the OCUM-9 genome. BORCS5-ETV6 possesses oncogenic activity, and suppression of its message partially inhibits cell growth. Prevalence of these novel fusion genes among SGC awaits further investigation, but we validate the significance of cell lines as appropriate reagents for detailed genomic analyses of SGC.

  Study JGAS000179

• Heterogeneity of IKZF1 genomic alterations and risk of relapse in childhood B-cell precursor acute lymphoblastic leukemia

  Purpose Genomic alterations of IKZF1 are common and associated with adverse clinical features in B-ALL, but the relationship between the type of IKZF1 alteration, disease subtype and outcome are incompletely understood. Patients and Methods We used transcriptome and genomic sequencing, and SNP microarray data to determine leukemia subtype and genomic alterations for 688 pediatric patients with B-ALL enrolled into St. Jude Total Therapy 15 and 16 studies. Results IKZF1 alterations were identified in 115 (16.7%) patients, commonly in BCR::ABL1 (78%) and CRLF2-rearranged, BCR::ABL1-like B-ALL (70%), and were associated with five-year cumulative incidence of relapse (CIR) of 14.8 ± 3.3% compared to 5.0 ± 0.9% for patients without any IKZF1 alteration (P < 0.0001). IKZF1 deletions of exon 4-7 (P = 0.0002), genomic IKZF1plus with any IKZF1 deletion (P = 0.006) or with focal IKZF1 deletion (P = 0.0007), and unfavorable genomic subtypes (P < 0.005) were independently adversely prognostic. Patients with both IKZF1 exon 4-7 deletion and unfavorable genomic subtype had a significantly increased risk of relapse (HR = 58.3; 95% CI, 11.9 – 285.4, P < 0.0001) whereas IKZF1 sequence mutations were not independently predictive of outcome. Conclusions Genomic IKZF1plus with any IKZF1 deletion, IKZF1 deletion of exon 4-7, and unfavorable subtype confer increased risk of relapse. The combination of unfavorable genomic subtype and IKZF1 deletion of exon 4-7 identified patients at greatest risk of relapse despite MRD-directed therapy. The type of IKZF1 alteration together with subtype are informative for risk stratification and predict response in patients with B-ALL.

  Study EGAS50000000106

• Case Report: Pre-Clinical Combination Targeting VEGF and PI3K in a Rare, Aggressive Mixed Endometrial Carcinoma

  We report a rare case of a young patient (VENUS 167) initially diagnosed with grade 1 endometrioid endometrial cancer, which, following endocrine treatment, presented with mixed aggressive carcinoma with three distinct histologic patterns: grade 1 endometrioid, large cell neuroendocrine, and undifferentiated carcinoma. The surgical specimen at the time of disease progression was used to establish OPTO.85, a patient-derived organoid (PDO), followed by a corresponding organoid-derived xenograft (ODX). Multi-omic analyses confirmed that OPTO.85 accurately reflected the patient’s tumor characteristics. WES analysis identified oncogenic alterations in PIK3CA, ARID1A, and CTNNB1. Further RNA-seq and ATAC-seq analyses revealed enrichment in VEGF and Wnt signaling pathways, suggesting therapeutic vulnerabilities. A high-throughput drug screen was conducted using ApexBio-Approved and Epigenetic Drug Libraries, along with Kinase Inhibitor and Tool Compound Libraries developed at the Ontario Institute of Cancer Research. The OPTO.85 PDO exhibited sensitivity to PI3K inhibitors and responsiveness to VEGF inhibition. Cediranib demonstrated synergy with BKM120, significantly reducing organoid growth. This combination also showed in vivo efficacy in the ODX model, where dual inhibitors significantly suppressed tumor growth compared to single compounds. This case exemplifies the impact of genomic profiling and patient-derived models in identifying actionable molecular changes in rare cancers with limited therapeutic options and poor prognosis. It highlights that high-throughput sequencing for individual patient tumors and generation of patient-derived models are feasible in endometrial cancer. This preclinical model may assist clinical decision and personalized therapy requiring validation in prospective studies.

  Study EGAS50000001665

• An autoinflammatory RIG-I variant causing Singleton-Merten Syndrome associates with small non-coding Y-RNAs

  The RNA sensor RIG-I performs a critical role in surveying the cytoplasm for the presence of viral nucleic acids and initiating the downstream anti-viral type I interferon pathway. Through recognition of specific features, such as the presence of a 5’ di/triphosphate motif or highly structured base-paired regions, RIG-I effectively differentiates between RNA of viral- and self-origin. In Singleton-Merten syndrome (SMS), gain-of-function variants in RIG-I lead to a breakdown in this surveillance system and results in aberrant sensing of self-RNAs and deleterious upregulation of type I interferons. The identity of the self-RNAs binding to gain-of-function RIG-I mutants has remained elusive and would provide a greater understanding of the aetiology of SMS. Here we used an infrared individual-nucleotide resolution UV-crosslinking and immunoprecipitation (irCLIP) approach to determine the RNA profile bound to a previously characterised ATPase-deficient SMS variant, RIG-IC268F. irCLIP identified a broad array of self-RNAs, primarily those transcribed by RNA polymerase III, that were bound to RIG-I. Subsequent native RNA immunoprecipitation confirmed a prominent and specific interaction between RIG-IC268F and Y-RNAs, a family of four structurally similar non-coding RNAs. Manipulation of Y-RNAs alone by targeting either Y-RNA transcripts or Y-RNA stabilising proteins was insufficient to negate RIG-I induce interferon, hinting at a broader profile of RNA polymerase III-derived RNAs being influential in driving the sterile activation of gain-of-function RIG-I variants.

  Study EGAS50000001660

• Detection of Clinically Relevant Genetic Variantsin Autism Spectrum Disorderby Whole-Genome Sequencing

  Autism Spectrum Disorder (ASD) demonstrates high heritability and familial clustering, yet the genetic causes remain only partially understood as a result of extensive clinical and genomic heterogeneity. Whole-genome sequencing (WGS) shows promise as a tool for identifying ASD risk genes as well as unreported mutations in known loci, but an assessment of its full utility in an ASD group has not been performed. We used WGS to examine 32 families with ASD to detect de novo or rare inherited genetic variants predicted to be deleterious (loss-of-function and damaging missense mutations). Among ASD probands, we identified deleterious de novo muta- tions in six of 32 (19%) families and X-linked or autosomal inherited alterations in ten of 32 (31%) families (some had combinations of mutations). The proportion of families identified with such putative mutations was larger than has been previously reported; this yield was in part due to the comprehensive and uniform coverage afforded by WGS. Deleterious variants were found in four unrecognized, nine known, and eight candidate ASD risk genes. Examples include CAPRIN1 and AFF2 (both linked to FMR1, which is involved in fragile X syndrome), VIP (involved in social-cognitive deficits), and other genes such as SCN2A and KCNQ2 (linked to epilepsy), NRXN1, and CHD7, which causes ASD-associated CHARGE syndrome. Taken together, these results suggest that WGS and thorough bioinformatic analyses for de novo and rare inherited mutations will improve the detection of genetic variants likely to be associated with ASD or its accompanying clinical symptoms.

  Study EGAS00001000850

• Sequencing data from triple-negative breast cancer tumors

  Autoimmunity and anti-cancer immunity lie on the same biological continuum1,2, but their link remains obscure. The paraneoplastic neurological syndrome anti-NMDA receptor (NMDAR) encephalitis (ANRE) is a paradigm for their connectivity3 given that intratumoral NMDAR expression correlates with the generation of anti-NMDAR antibodies4,5. Here, we verify ectopic expression of GluN1 and GluN2B NMDAR sub-units in triple-negative breast cancer (TNBC)6 and model this using orthotopic TNBC tumors with inducible expression of GluN1-GluN2B NMDARs. We show that NMDAR expression is sufficient to induce B cell recruitment and their affinity maturation, consistent with an integrated adaptive immune response. Reconstruction of extended intratumoral B cell phylogenies and cryo-EM structural analyses demonstrated that affinity-matured hypermutated and class-switched antibodies emerged from pre-existing germline-configuration lower-affinity anti-NMDAR antibodies. Distinct matured antibodies targeted specific epitopes and induced conformational rearrangements within the NMDAR amino-terminal domain, predictive of their functional effects, ranging from inhibition to potentiation. Passive transfer of an NMDAR-potentiating antibody caused autonomic dysregulation and lowered the seizure threshold in healthy female mice, recapitulating key diagnostic criteria of ANRE4,5. We further identify a correlation between intratumoral NMDAR expression and anti-NMDAR antibody titers in TNBC patients. Taken together, our data establish a direct connection between intratumoral NMDAR expression, antibody maturation, and the onset of autoimmunity. These findings suggest that germline-encoded anti-NMDAR antibodies contribute to immune surveillance but can also trigger autoimmune disease upon maturation, revealing a mechanistic tradeoff between cancer immunity and neurotoxicity.

  Study EGAS50000001585

• Sequencing data from triple-negative breast cancer tumors

  Autoimmunity and anti-cancer immunity lie on the same biological continuum1,2, but their link remains obscure. The paraneoplastic neurological syndrome anti-NMDA receptor (NMDAR) encephalitis (ANRE) is a paradigm for their connectivity3 given that intratumoral NMDAR expression correlates with the generation of anti-NMDAR antibodies4,5. Here, we verify ectopic expression of GluN1 and GluN2B NMDAR sub-units in triple-negative breast cancer (TNBC)6 and model this using orthotopic TNBC tumors with inducible expression of GluN1-GluN2B NMDARs. We show that NMDAR expression is sufficient to induce B cell recruitment and their affinity maturation, consistent with an integrated adaptive immune response. Reconstruction of extended intratumoral B cell phylogenies and cryo-EM structural analyses demonstrated that affinity-matured hypermutated and class-switched antibodies emerged from pre-existing germline-configuration lower-affinity anti-NMDAR antibodies. Distinct matured antibodies targeted specific epitopes and induced conformational rearrangements within the NMDAR amino-terminal domain, predictive of their functional effects, ranging from inhibition to potentiation. Passive transfer of an NMDAR-potentiating antibody caused autonomic dysregulation and lowered the seizure threshold in healthy female mice, recapitulating key diagnostic criteria of ANRE4,5. We further identify a correlation between intratumoral NMDAR expression and anti-NMDAR antibody titers in TNBC patients. Taken together, our data establish a direct connection between intratumoral NMDAR expression, antibody maturation, and the onset of autoimmunity. These findings suggest that germline-encoded anti-NMDAR antibodies contribute to immune surveillance but can also trigger autoimmune disease upon maturation, revealing a mechanistic tradeoff between cancer immunity and neurotoxicity.

  Study EGAS50000001598

• Capturing disease severity in LIS1-lissencephaly reveals proteostasis dysregulation in patient-derived forebrain organoids

  Lissencephaly is a developmental cortical malformation characterized by reduced to absent gyri and a disorganized cortex, often leading to severe impairments in affected individuals and a reduced life expectancy. Heterozygous mutations in the LIS1 gene, encoding a regulator of the microtubule motor dynein, cause lissencephaly with different clinical severities. While the clinical disease spectrum correlates with the degree of lissencephaly, location and type of mutation may not. We leveraged forebrain-type organoids from LIS1-lissencephaly patients, diagnosed with mild, moderate or severe lissencephaly to investigate, in a cytoarchitecture and multi-omics approach, how the severity degree in patients might relate to specific mutations in the LIS1 gene. We questioned which processes during cortical development might be differentially affected by severity grade, and whether they could be pharmacologically targeted. We found alterations in neurodevelopment often with a severity-dependent gradient. Specifically, we identified alterations of the cytoarchitecture, progenitor cell homeostasis and neurogenesis. Particularly important disease-linked molecular mechanisms were microtubule destabilization, WNT-signaling, and perturbed cadherin- and unfolded protein-binding. Some mechanisms exhibited a severity-dependent gradient, or were specific to a severe grade. We present strategies to reverse phenotypic changes in LIS1-patient organoids, and an in silico approach with therapeutic potential. Thus, we show that different LIS1-severity grades can be recapitulated in vitro, that there is a direct link between the phenotype and genotype, that organoid-based disease modeling can identify molecular underpinnings of malformations of cortical development and that organoids provide a valid platform to develop and test therapeutic strategies.

  Study EGAS00001008227

• DNA methylation and the adverse metabolic outcomes of adiposity

  Overweight and obesity affect ~1.5 billion people worldwide, and are major risk factors for type-2 diabetes (T2D), cardiovascular disease and related metabolic and inflammatory disturbances.1,2 Although the mechanisms linking adiposity to its clinical sequelae are poorly understood, recent studies suggest that adiposity may influence DNA methylation,3-6 a key regulator of gene expression and molecular phenotype.7 Here we use epigenome-wide association to show that body mass index (BMI, a key measure of adiposity) is associated with widespread changes in DNA methylation (187 genetic loci at P&lt;1x10-7, range P=9.2x10-8 to 6.0x10-46; N=10,261 samples). Genetic association analyses demonstrate that the alterations in DNA methylation are predominantly the consequence of adiposity, rather than the cause. We find the methylation loci are enriched for functional genomic features in multiple tissues (P&lt;0.05), and show that sentinel methylation markers identify gene expression signatures at 38 loci (P&lt;9.0x10-6, range P=5.5x10-6 to 6.1x10-35, N=1,785 samples). The methylation loci identified highlight genes involved in lipid and lipoprotein metabolism, substrate transport, and inflammatory pathways. Finally, we show that the disturbances in DNA methylation predict future type-2 diabetes (relative risk per 1SD increase in Methylation Risk Score: 2.3 [2.07-2.56]; P=1.1x10-54). Our results provide new insights into the biologic pathways influenced by adiposity, and may enable development of new strategies for prediction and prevention of type-2 diabetes and other adverse clinical consequences of obesity.

  Study EGAS00001001922

• Immunodeficiency syndrome caused by LCP1 mutations

  Severe congenital neutropenia (SCN) is characterized by neutropenia, recurrent infections and an increased leukemia risk. Multiple genetic defects underlying SCN have been identified, but a genetic diagnosis is still lacking in a significant proportion of patients. Here, we report three independent pedigrees with autosomal dominant variants in LCP1. Variants c.740-1G&gt;T and c.740-20_744del resulted in the same alternatively spliced RNA product, causing an in-frame deletion (p.A247_E254del). Variant c.509C&gt;T in the third pedigree resulted in p.S170L. Variant carriers suffer from neutropenia, poor or complete lack of response to G-CSF treatment, and variable degrees of lymphopenia. Patients with A247_E254del presented with tetraploid cells in the bone marrow, indicative of disturbed cytokinesis. In one of these kindreds, two individuals developed acute leukemia. G-CSF non-responsiveness and defective cell cycling were repaired upon correction of the LCP1 A247_E254del variant in patient-derived induced pluripotent stem cells, supporting the monogenic origin of the disease. Indicative of their gain-of-function, both A247_E254del and S170L variants increased F-actin bundling and formation of abnormal protrusions. Single-cell transcriptome analysis of A247_E254del bone marrow-derived hematopoietic stem and progenitor cells (HSPCs) showed deregulation of signaling pathways controlling mitosis in multi-lineage and lymphoid-primed HSPC subsets. We conclude that activating LCP1 variants cause a new autosomal dominant hematopoietic disorder. Depending on the consequences of the LCP1 variants for protein structure, patients may suffer from G-CSF refractory severe neutropenia, lymphopenia, defective cytokinesis and predisposition to leukemia.

  Study EGAS00001008293

• The genomic landscape of pediatric acute lymphoblastic leukemia

  Acute lymphoblastic leukemia (ALL) is the most common pediatric cancer and arises from B- or T-lineage lymphocyte precursors. ALL comprises dozens of subtypes, and genomic analyses have largely been performed within these subtypes. Here we analyze pediatric ALL genomes across all subtypes, including 768 whole genomes, 1,729 exomes, and 1,889 transcriptomes in 2,754 patients. Most ALL subtypes harbor 4 or more driver alterations per sample, similar to adult cancers, despite low mutation burdens. Hyperdiploid B-ALL copy gains are likely acquired early and synchronously, with copy gains occurring before ultraviolet-induced mutations. By contrast, ultraviolet-induced mutations precede copy gains in iAMP21 B-ALL. Overall, we identified 378 putative ALL driver genes. Most driver alterations vary in prevalence across ALL subtypes, with B-ALL enriched for Ras and B-lineage-related alterations, and T-ALL enriched for PI3K, JAK, and cell cycle alterations. Most B-ALL (54.3%) and T-ALL (51.2%) samples bear at least one rare driver gene alteration (present in less than 2% of samples), including 30 putative novel cancer driver genes associated with ubiquitination, SUMOylation, non-coding, and other functions. Known or novel alterations associated with poor outcomes in specific subtypes include TBL1XR1 alterations in ETV6-RUNX1 patients, CREBBP in Ph-like-CRLF2, SETD2 in hyperdiploid, and PTEN in TAL1 patients. Intriguingly, DUX4 and KMT2A subtypes separate into CEBPA/FLT3- or NFATC4-expressing subgroups with potential clinical implications. Together, these results deepen understanding of ALL etiology and outcomes, and facilitate ALL model development.

  Study EGAS00001005250

• Organoid cultures of early-onset colorectal cancers reveal distinct and rare genetic profiles

  Sporadic early-onset colorectal cancer (EOCRC) has bad prognosis, yet is poorly represented by cell line models. We examine the key mutational and transcriptomic alterations in an organoid biobank enriched in EOCRCs. We established paired cancer (n=32) and normal organoids (n=18) from 20 patients enriched in microsatellite-stable EOCRC. Exome and transcriptome analysis was performed. We observed a striking diversity of molecular phenotypes, including PTPRK-RSPO3 fusions. Transcriptionally, RSPO fusion organoids resembled normal colon organoids and were distinct from APC mutant organoids, with high BMP2 and low PTK7 expression. Single cell transcriptome analysis confirmed the similarity between RSPO fusion organoids and normal organoids, with a propensity for maturation on Wnt withdrawal, whereas the APC mutant organoids were locked in progenitor stages. CRISPR/Cas9 engineered mutation of APC in normal human colon organoids led to upregulation of PTK7 protein and suppression of BMP2, but less so with an engineered RNF43 mutation. The frequent co-occurrence of RSPO fusions with SMAD4 or BMPR1A mutation was confirmed in TCGA database searches. RNF43 mutation was found in organoid from a leukaemia survivor with a novel mutational signature; and organoids with POLE proofreading mutation displayed ultramutation. The cancer organoid genomes were stable over long culture periods, while normal human colon organoids tended to be subject to clonal dominance over time. These organoid models enriched in EOCRCs with linked genomic data fill a gap in existing CRC models and reveal distinct genetic profiles and novel pathway cooperativity.

  Study EGAS00001004063

• Single cell RNA-seq mapping of nasal and tracheobronchial airways in human healthy volunteers

  The respiratory tract constitutes an elaborated line of defense based on a unique cellular ecosystem. Single-cell profiling methods enable the investigation of cell population distributions and transcriptional changes along the airways. We have explored cellular heterogeneity of the human airway epithelium in 10 healthy living volunteers by single-cell RNA profiling. 77,969 cells were collected by bronchoscopy at 35 distinct locations, from the nose to the 12th division of the airway tree. The resulting atlas is composed of a high percentage of epithelial cells (89.1%), but also immune (6.2%) and stromal (4.7%) cells with peculiar cellular proportions in different sites of the airways. It reveals differential gene expression between identical cell types (suprabasal, secretory, and multiciliated cells) from the nose (MUC4, PI3, SIX3) and tracheobronchial (SCGB1A1, TFF3) airways. By contrast, cell-type specific gene expression was stable across all tracheobronchial samples. Our atlas improves the description of ionocytes, pulmonary neuro-endocrine (PNEC) and brush cells, which are likely derived from a common population of precursor cells. We also report a population of KRT13 positive cells with a high percentage of dividing cells which are reminiscent of “hillock” cells previously described in mouse. Robust characterization of this unprecedented large single-cell cohort establishes an important resource for future investigations. The precise description of the continuum existing from nasal epithelium to successive divisions of lung airways and the stable gene expression profile of these regions better defines conditions under which relevant tracheobronchial proxies of human respiratory diseases can be developed.

  Study EGAS00001004082

• Targeted and shallow whole genome sequencing identifies therapeutic opportunities in p53abn endometrial cancers

  Purpose: Shallow whole genome sequencing (sWGS) can detect copy number (CN) aberrations. In high-grade serous ovarian (HGSOC) sWGS identified CN signatures such as homologous recombination deficiency (HRD) to direct therapy. We applied sWGS with targeted sequencing to p53abn endometrial cancers (ECs) to identify additional prognostic stratification and therapeutic opportunities. Experimental Design: sWGS and targeted panel sequencing was performed on formalin-fixed paraffin-embedded p53abn ECs. CN alterations, mutational data and CN signatures were derived, and associations to clinicopathologic and outcomes data were assessed. Results: In 187 p53abn ECs, 5 distinct CN signatures were identified. Signature 5 was associated with BRCA1/2 CN loss with features similar to HGSOC HRD signature. 22% potential HRD cases were identified, 35 patients with signature 5, and 8 patients with BRCA1/2 somatic mutations. Signatures 3 and 4 were associated with whole genome duplication, and CCNE1, ERBB2 and MYC amplifications, with mutations in PIK3CA enriched in signature 3. We observed improved overall survival (OS) for patients with signature 2 and worse OS for signatures 1 and 3. 28% of patients had CCNE1 amplification and this subset was enriched with carcinosarcoma histotype. 34% of patients, across all histotypes, had ERBB2 amplification and/or HER2 overexpression on immunohistochemistry, which was associated with worse outcomes. Mutations in PPP2R1A (29%) and FBXW7 (16%) were among the top 5 most common mutations. Conclusions: sWGS and targeted sequencing identified therapeutic opportunities in 75% of p53abn EC patients. Further research is needed to determine the efficacy of treatments targeting these identified pathways within p53abn ECs.

  Study EGAS00001007661

• Pediatric Papillary Thyroid Carcinoma Whole Exome Sequencing

  BACKGROUND: Pediatric papillary thyroid carcinoma (PPTC) is distinct from adult-onset disease. Despite higher rates of regional and distal metastases and more frequent recurrence, there is, paradoxically, a highly favourable prognosis. Historically, only 40-50% of childhood PTC are driven by genomic variants common to adult PTC, while the oncogenic drivers in the remainder are unknown. METHODS: Fifty-two PPTCs were genotyped by candidate gene testing, followed, in a subset (n=32), by whole exome (WES) and transcriptome sequencing (RNASeq) to identify oncogenic variants in driver-unknown tumors and to explore gene expression patterns. FINDINGS: Thirty-one tumors (60%) carried variants identified by candidate gene testing, specifically: BRAFV600E(22%), NRASQ61R(2%), RET-CCDC6(19%), RET-NCOA4(15%) and PAX8-PPARG. Among the 21 remaining tumors with negative first-line genotyping, oncogenic variants were identified in 19 (90%). These were enriched with oncogenic fusions, with 11 non-recurrent fusion transcripts identified, including two that had not been previously described: STRN-RET and TG-PBF. Most fusions were associated with 3’ receptor tyrosine kinase (RTK) moieties: RET, MET, ALK and NTRK3. Gene expression analysis defined three distinct clusters, which demonstrated differing expression of genes involved in thyroid differentiation and MAPK signaling. INTERPRETATION: Exome and transcriptome-wide sequencing identify genomic drivers of PPTC in 98% of tumors, whereas conventional genotyping leaves many tumors genetically unexplained. PPTC is driven, in the majority of cases, by oncogenic fusion transcripts involving one of a limited number of RTKs. These observations have broad implications for diagnostic testing and for therapeutic options in children with advanced disease.

  Study EGAS00001005187

• WES analysis of a mixed cohort of pituitary tumors

  BACKGROUND: Sporadic pituitary adenomas are the second most common primary brain tumor, but their genetics remains incompletely understood. We performed deep DNA sequencing of 42 pituitary macroadenomas, including hormonally active and atypical adenomas. METHODS: Pituitary adenomas representative of a spectrum of histopathologic subtypes, primary and recurrent tumors, and MIB-1 proliferative indices were profiled. Whole-exome sequencing was performed on tumors and paired blood followed by analysis of somatic copy number alteration and mutation. RESULTS: On the whole, the tumors harbored a low rate of mutations, similar to other benign brain tumors. However, almost one-third (29%) exhibited somatic copy-number alterations across large fractions of the genome (up to 99%). Despite such widespread genomic disruption, these tumors had few focal events, which is atypical among highly-disrupted cancers. The other 71% of tumors formed a distinct molecular class, with somatic copy-number alterations involving less than 6% of the genome. Among the highly-disrupted group, 92% were functional or atypical null-cell adenomas, whereas 87% of the less-disrupted group were clinically non-functional adenomas. The only significantly recurrent events were arm-level losses of chromosomes 1, 2, 11, and 18. No significantly recurrent mutations or insertion/deletion events were identified, suggesting no genes are altered by exomic mutations in &gt;15% of pituitary tumors. CONCLUSIONS: Genomic characterization of a large series of sporadic pituitary adenomas reveals two classes of tumor, based on genomic disruption from arm-level copy-number alterations, which associate with hormonal and histologic subtypes.

  Study EGAS00001001714

• C3 SNPs and outcome after lung transplantation

  Background: Development of chronic rejection is still a severe problem and causes high mortality rates after lung transplantation (LTx). Complement activation is important in the development of acute rejection (AR) and bronchiolitis obliterans syndrome, with C3 as a key complement factor. Methods: Since a single nucleotide polymorphism (SNP) in the C3 gene (rs2230199) is associated with long-term outcome after solid organ transplantation, we investigated this SNP in relation to LTx. In addition, we looked at local production of C3 by analyzing bronchoalveolar lavage fluid (BALF) of LTx patients using isoelectric focusing (IEF). Results: We demonstrated the presence of C3 in BALF and showed that this is produced by the donor lung based on the genotype of SNP rs2230199. We also analyzed donor and patient SNP configurations and observed a significant association between the SNP configuration in patients and episodes of AR during 4-years follow-up. Survival analysis showed a lower AR-free survival in homozygous C3 slow patients (p=0.005). Furthermore, we found a significant association between the SNP configuration in donors and BOS development. Patients receiving a graft from a donor with at least one C3 fast variant for rs2230199 had an inferior BOS-free survival (p=0.044). Conclusions: In conclusion, our data indicate local C3 production by donor lung cells. In addition, a single C3 SNP present in recipients affects short-term outcome after LTx, while this SNP in donors has an opposite effect on long-term outcome after LTx. These results could contribute to an improved risk stratification after transplantation.

  Study EGAS00001003843

• whole genome sequence data of multifocal hepatocellular carcinoma

  Background &amp; Aims: The differentiation of distinct multifocal hepatocellular carcinoma (HCC): multicentric disease vs. intrahepatic metastases, in which the management and prognosis varies substantively, remains problematic. We aim to stratify multifocal HCC and identify novel diagnostic and prognostic biomarkers by performing whole genome and transcriptome sequencing, as part of a multi-omics strategy Methods: A complete collection of tumour and somatic specimens (intrahepatic HCC lesions, matched non-cancerous liver tissue and blood) were obtained from representative patientswith multifocal HCC exhibiting two distinct postsurgical courses. Whole-genome and transcriptome sequencing with genotyping were performed for each tissue specimen to con-trast genomic alterations, including hepatitis B virus integrations, somatic mutations, copy number variations, and structural variations. We then constructed a phylogenetic tree to visualise individual tumour evolution and performed functional enrichment analyses on select differentially expressed genes to elucidate biological processes involved in multifocal HCC development. Multi-omics data were integrated with detailed clinicopathological information to identify HCC biomarkers, which were further validated using a large cohort of HCC patients (n = 174).Results: The multi-omics pro?ling and tumour biomarkers could successfully distinguish the two multifocal HCC types, while accurately predicting clonality and aggressiveness. The dual speci?city protein kinase TTK, which is a key mitotic checkpoint regulator with links to p53 signaling, was further shown to be a promising overall prognostic marker for HCC in the large patient cohort.Conclusions: Comprehensive multi-omics characterisation of multifocal tumour evolution may improve clinical decision-making, facilitate personalised medicine, and expedite identi?cation of novel biomarkers and therapeutic targets in HCC.

  Study EGAS00001002338

• Analysis of recent shared ancestry in a familial cohort identifies coding and noncoding autism spectrum disorder variants

  Autism spectrum disorder (ASD) is a collection of neurodevelopmental disorders characterized by deficits in social communication and restricted, repetitive patterns of behavior or interests. ASD is highly heritable, but genetically and phenotypically heterogeneous, reducing the power to identify causative genes. We performed whole genome sequencing (WGS) in an ASD cohort of 68 individuals from 22 families enriched for recent shared ancestry. We identified an average of 3.07 million variants per genome, of which an average of 112,512 were rare. We mapped runs of homozygosity (ROHs) in affected individuals and found an average genomic homozygosity of 9.65%, consistent with expectations for multiple generations of consanguineous unions. We identified potentially pathogenic rare exonic or splice site variants in 12 known (including KMT2C, SCN1A, SPTBN1, SYNE1, ZNF292) and 12 candidate (including CHD5, GRB10, PPP1R13B) ASD genes. Furthermore, we annotated noncoding variants in ROHs with brain-specific regulatory elements and identified putative disease-causing variants within brain-specific promoters and enhancers for 5 known ASD and neurodevelopmental disease genes (ACTG1, AUTS2, CTNND2, CNTNAP4, SPTBN4). We also identified copy number variants in two known ASD and neurodevelopmental disease loci in two affected individuals. In total we identified potentially etiological variants in known ASD or neurodevelopmental disease genes for ~61% (14/23) of affected individuals. We combined WGS with homozygosity mapping and regulatory element annotations to identify candidate ASD variants. Our analyses add to the growing number of ASD genes and variants and emphasize the importance of leveraging recent shared ancestry to map disease variants in complex neurodevelopmental disorders.

  Study EGAS00001006058

• Somatic mutations predict an aggressive phenotype in meningioma but do not drive grade progression

  A subset of meningiomas progress in histopathological grade and drivers of progression are poorly understood. We aimed to identify somatic mutations and copy number alterations (CNAs) associated with grade progression in a unique matched tumour dataset. Utilising a prospective database, we identified 10 patients with meningiomas that had undergone grade progression and for whom matched pre- and post-progression tissue (n=50 samples) was available for targeted next-generation sequencing. Mutations in NF2 were identified in 4/10 patients, 94% were non-skull base tumours. In one patient, three different NF2 mutations were identified in four tumours. NF2 mutated tumours showed large scale CNAs, with highly recurrent losses in 1p, 10, 22q, and frequent CNAs on chromosomes 2, 3 and 4. There was a correlation between grade and CNAs in a subset of patients. In two patients with sphenoid wing Grade III tumours without detected NF2 mutations, a STAT6-NAB2 inversion was identified. Two patients with tumours without detected NF2 mutations showed a combination of loss and high gain on chromosome 17q. Mutations in SETD2, TP53, TERT promoter and NF2 were not uniform across recurrent tumours and did not correspond with grade progression. Meningiomas that progress in grade generally have a mutational profile already detectable in the pre-progressed tumour, suggesting an aggressive phenotype . CNA profiling shows frequent alterations in NF2 mutated tumours compared to non NF2 mutated tumours and the pattern of CNAs may be associated with grade progression in a subset of cases.

  Study EGAS00001006585