12433 results for ""non-traditional+communal+storytelling+approach"+novel+segment+noted+in+critical+commentary"

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• Genomic Heterogeneity and the Small Renal Mass

  Tumor heterogeneity is believed to represent a barrier to pre-operative genomic characterization in kidney cancer. Previous studies of heterogeneity in clear cell renal cell carcinoma (ccRCC) evaluated only large and metastatic tumors. In small renal tumors in which multiple biopsies are not feasible, the extent of heterogeneity remains unknown. In this study, we evaluated how the extent of genomic heterogeneity in small and large ccRCC. A total of 23 small (<4cm ) and 24 large (>7cm ) ccRCC had 3 regions sampled for evaluation of copy number, clear-cell A/clear-cell B (ccA/ccB) classification, and cell cycle progression (CCP) score. Small tumors have less genomic complexity and significantly fewer subclonal events. Pre-treatment genomic characterization based on a single biopsy in small ccRCC can provide insight into biologic potential to make clinical decisions.

  Study EGAS00001002919

• MuTHER_adipose_tissue_small_RNA_expression

  We investigate the naturally occurring variation of small RNA expression in conjunction with genetic and gene expression variation. We shall assess the variation in subabdominal fat tissue small RNA levels in 168 unrelated MuTHER individuals. Using gene expression data from the same samples, we can survey how much the small RNA expression contributes to the variance in gene expression profiles. We can also take advantage of the high density genotyping data on these samples to identify genetic associations of small RNA expression levels, and the downstream effect of the genetic variants in small RNA sequence. Previous small RNA sequencing efforts have also extended the repertoire of small RNAs, and we hope to potentially find additional small RNAs active in adipose tissue biology. Altogether, the project should provide an exciting view into small RNA biology in humans, and lead to development of new methodology for analysis of molecular phenotype data.

  Study EGAS00001000212

• BLUEPRINT DNA Methylation 450K data of mantle cell lymphoma

  We have applied an analytic strategy to decipher the DNA methylome of 86 mantle cell lymphomas (MCL) in light of the methylome of the entire B-cell lineage. In this way, we first identified two MCL subgroups that respectively carry epigenetic imprints of pre- and post-germinal center B cells. Secondly, we observed that pure tumor-specific changes are rare, as most (89-99%) DNA methylation alterations in MCL are within or in close proximity of those regions showing dynamic methylation in normal B cells. Several thousand of these differentially methylated regions in MCL show concurrent changes in enhancer-associated histone modifications, including a region located 650 Kb away from the MCL oncogene SOX11. At the clinical level, epigenetic and genetic changes co-evolve during MCL progression and the magnitude of epigenetic changes is associated with overall survival of the patients.

  Study EGAS00001001637

• Germline RUNX1 Variation and Predisposition to Childhood Acute Lymphoblastic

  Somatic mutations of RUNX1, which encodes the myeloid and lymphoid transcriptional factor RUNX1, are common in both B- and T- acute lymphoid leukemia (ALL) and are associated with poor prognosis of T-ALL. However, there has been no comprehensive investigation of the pattern or prevalence of RUNX1 germline mutation in both B- and T-ALL. Here we report germline RUNX1 variants in 1.23% of B-ALL and 2.11% of T-ALL, identifying 31 unique variants in 62 B-ALL and 18 unique variants in 26 T-ALL children. The majority of frameshift and nonsense variants affected RUNX1 function in transcriptional regulation, hematopoiesis, and cellular proliferation. We identified JAK3 as the most frequent somatic mutation in T-ALL with RUNX1 variants. These results not only identify RUNX1 as a leukemia predisposition gene but also further underline the importance of germline genetic variants to the development of ALL

  Study EGAS00001005403

• Gene copy number variation in pediatric mental illness in a general population

  We assessed the relationship of gene copy number variation (CNV) in mental health/neurodevelopmental traits and diagnoses, physical health, and cognitive biomarkers in a community sample of 7,100 unrelated European, and East Asian children and youth (Spit for Science). Diagnoses of mental health disorders were found in 17.5% of participants and 27.6% scored in the highest 10% on either or both ADHD and OCD trait measures. Clinically relevant CNVs were present in 3.9% of participants and were associated with elevated scores on a continuous measure of ADHD (p=5.0×10-3), on a cognitive biomarker of mental health (response inhibition (p=1.0×10-2)), and on prevalence of mental disorders (p=1.9×10-6, odds ratio: 3.09). With a rise of mental illness, our data establishes a baseline for delineating genetic contributors in paediatric-onset conditions.

  Study EGAS00001006659

• single-stranded DNA study

  A ssDNA library protocol was applied to cfDNA from plasma samples obtained from different DNA extraction methods and revealed significant differences in DNA fragmentation patterns in comparison to dsDNA-based protocols. In particular, a specific combination of methods revealed a population of ultrashort fragments, organized at ~50 bp. We observed significant differences in the relative abundance of these ultrashort DNA fragments in plasma from healthy individuals and cancer patients. Through shallow whole genome sequencing (sWGS, <0.5-fold coverage) and the analysis of somatic copy number aberrations (SCNA), we determined the landscape of genetic alterations in this newly identified population of cfDNA fragments. In addition, we studied their potential link with regulatory regions by investigating the genome-wide coverage patterns at transcription start sites (TSS). Furthermore, we demonstrated that the ultrashort cfDNA fragments map to regions associated with secondary DNA structures, G-quadruplexes (G4s).

  Study EGAS00001005093

• Analysis of a cohort of familial ademomatous polyposis patients bearing APC gene mutation

  large number of colorectal adenomas with high risk of evolving into colorectal tumors. Mutations of the Adenomatous polyposis coli (APC) gene is often at the origin of this disease, as well as of a high percentage of spontaneous colorectal tumors. APC is therefore considered a tumor suppressor gene. While the role of APC in intestinal epithelium homeostasis is well characterized, its importance in immune responses remains ill defined. We investigated an array of immune cell features in FAP subjects carrying APC mutations. A group of 12 FAP subjects and age and sex-matched healthy controls were studied. In particular, the expression of 579 immune response genes was analyzed in whole blood cells using the Nanostring nCounter Human Immunology kit v2. (Cuche C. et al. Frontiers in Immunology, 2023, in press)

  Study EGAS00001007237

• Molecular Characterization of Hemimegalencephaly

  Somatic mutations, in which a fraction of the cells in the body have a deleterious mutation, are well recognized in cancer but only recently appreciated in neurological disease. Given a somatic mutation in a population of progenitor cells, all daughter cells inherit the mutation and are able to express the resultant phenotype as a function of the differentiation program. We recently identified the first de novo somatic mutations in the developing brain in the condition hemimegalencephaly (HME), a catastrophic focal epilepsy condition associated with a malformation of cerebral cortical development (MCD). HME is one of the most severe MCD syndromes, characterized by massive hamartomatous overgrowth of either of the two cerebral hemispheres. Cerebral hemispherectomy is a frequent treatment for refractory epilepsy, allowing the sampling of diseased tissue. By comparing DNA from a diseased brain with DNA from blood/saliva, we identified de novo somatic mutations in PIK3CA, AKT3 or MTOR, part of the mTOR pathway. Mutations were present in 8-40% of sequenced alleles in various brain regions sampled during surgery and in some codons known to activate proteins.• Population informationPatient samples were collected from multiple centers. The population is Caucasian and Hispanic• Molecular technologies employedWhole-exome sequencing• Principal findings of the studyWe were the first to describe mTOR-related and non-mTOR mutations causing hemimegalencephaly, and we described two-hit mutational models to explain the genetic pathogenesis of hemimegalencephaly

  Study phs002156

• Platelet RNAseq data for SLFN14 K219N patients

  Pathogenic missense variants in SLFN14, which encodes an RNA endoribonuclease protein that regulates rRNA degradation, are known to cause inherited thrombocytopenia with impaired platelet aggregation and ATP secretion. Despite rather mild laboratory defects, these patients display an obvious bleeding phenotype. The function of SLFN14 in megakaryocyte (MK) and platelet biology is unknown. This study aims to characterize the platelet transcriptome in patients with a SLFN14 K219N variant and model the disease in the immortalized megakaryocyte cell line imMKCL. Total platelet RNA was sequenced for two patients and 19 healthy controls. Differential gene expression analysis yielded a total of 2999 and 2888 significantly (|log2FC|>1, FDR<0.05) up- and downregulated genes, respectively. Remarkably, these downregulated genes were not enriched for any biological pathway while upregulated genes were enriched for pathways involved in (mitochondrial) translation and transcription with a significant upregulation of 134 ribosomal protein genes (RPG). Heterozygous and homozygous SLFN14 K219N imMKCL showed a defect in MK differentiation that aggravated during cell passaging of undifferentiated cells and in proplatelet formation. SLFN14 defective platelets and MK showed signs of rRNA degradation while this was absent in undifferentiated imMKCL cells. Upregulation of RPG through increased mTOR signaling in SLFN14 K219N MK seems to be a compensatory response for rRNA degradation. Indeed, mTOR inhibition with rapamycin resulted in further enhanced rRNA degradation in SLFN14 K219N MK. Taken together, our study indicates dysregulation of mTOR-regulated ribosomal biogenesis as the disease mechanism for SLFN14-related thrombocytopenia.

  Study EGAS00001006339

• Genetic and epigenetic characterization of adenoid cystic carcinoma

  Translocation events are frequent in cancer and may create chimeric fusions or regulatory rearrangements that drive oncogene overexpression. Although regulatory rearrangements are increasingly recognized in hematopoietic and even solid tumors, the underlying mechanisms remain obscure. Here we identify super-enhancer translocations that drive overexpression of the oncogenic transcription factor MYB as a unifying theme in adenoid cystic carcinoma (ACC). Whole genome sequencing data and chromatin state maps for 13 primary tumors and xenografts reveal distinct chromosomal rearrangements that juxtapose super-enhancer clusters to the MYB locus. Chromosome conformation capture confirms that the translocated enhancers physically interact with the MYB promoter. Remarkably, the MYB product itself binds to the translocated enhancers, thus creating a positive feedback loop that sustains its own expression. MYB also binds a large number of active enhancers that drive opposing regulatory programs in alternate cell lineages in ACC. MYB cooperates with the transcription factor TP63 in the myoepithelial component of the tumors, but promotes a Notch program in the luminal epithelial component. Bromodomain inhibitors, which disrupt enhancer function, slow tumor growth in ACC primagraft models in vivo, but are ineffective against high grade tumors that harbor activating mutations in the Notch pathway. Thus, our study identifies super-enhancer translocations as a unifying feature of ACC, and provides insight into the mechanism by which sustained MYB overexpression drives alternate cell fates in this disease.Processed ChIP-seq data is available on GEO under accession number GSE76465.

  Study EGAS00001001457

• Exome Sequencing of Statin-Induced Myopathy Cases

  Severe myopathic events occur in 0.1-0.5% of patients taking statins. Although genetic association studies have identified some possibly associated gene loci, these have not been reproducible in additional studies with independent patient cohorts. A more reasonable explanation for susceptibility to statin-induced myopathy is the presence of rare pathogenic variants in genes important for skeletal muscle structure and function. In support of this, we have previously reported an increased incidence of pathogenic variants in genes causing metabolic myopathies in patients with statin-induced myopathy (Vladutiu et al.,2006). We also reported a patient with statin myopathy who had an RYR1 variant known to be causative of malignant hyperthermia susceptibility (MHS) (Vladutiu et al., 2011). There are a number of genes associated with metabolic myopathies triggered by various factors such as extreme exercise, fasting, extremes in temperature, viral infection and exposure to volatile anesthetics. In addition, many of the genes causing congenital myopathies, myofibrillar myopathies and muscular dystrophies have overlapping phenotypes with these genes. We propose that statins act as an additional trigger inducing myopathic symptoms and many patients with severe statin-induced myopathy have causative genetic variants within similar genes associated with MHS and congenital myopathy. We have analyzed the resultant data using a disease model in which rare pathogenic variants, possibly within multiple genes, are causative of statin-induced myopathy. In this study, we have identified potentially causative genetic variants in greater than 50% of the statin-induced myopathy cases and in particular, rare and possibly pathogenic in the RYR1 and CACNA1S genes were present in 25% of the patient samples studied. Vladutiu, G. D., Simmons, Z., Isackson, P.J., Tarnopolsky, M., Peltier, W.L., Barboi, A.C., Sripathi, N., Wortmann, R.L., Phillips, P.S., (2006). "Genetic risk factors associated with lipid-lowering drug-induced myopathies." Muscle Nerve 34: 153-162. Vladutiu, G. D., Isackson, P.J., Kaufman, K., Harley, J.B., Cobb, B., Christopher-Stine, L., Wortmann, R.L, (2011). "Genetic risk for malignant hyperthermia in non-anesthesia-induced myopathies." Mol Genet Metab 104: 167-173.

  Study phs001342

• Driver mutations in histone H3.3 and chromatin remodelling genes in paediatric glioblastoma

  Sequence reads for pediatric GBM samples for manuscript: Driver mutations in histone H3.3 and chromatin remodelling genes in paediatric glioblastoma

  Dataset EGAD00001000134

• Long read whole genome sequencing data from brain postmortem tissue

  Chart genetic variation in the human brain in healthy controls and Parkinson’s disease (PD) patients.

  Study EGAS50000000921

• Copy Number Variation using Affymetrix Optima Array

  Diagnostic yield of affymetrix optima microarray in patients with non-syndromic autism spectrum disorders in India.

  Study EGAS00001006439

• Single cell transcriptome atlas of immune cells in human small intestine and in Celiac disease

  Single cell transcriptome atlas of immune cells in human small intestine and in Celiac disease

  Dataset EGAD00001005127

• Geographic and age-related variations in mutational processes in colorectal cancer - patient metadata files (Mutographs)

  Geographic and age-related variations in mutational processes in colorectal cancer - patient metadata files (Mutographs)

  Dataset EGAD00001015437

• Geographic and age-related variations in mutational processes in colorectal cancer - copy number variants (Mutographs)

  Geographic and age-related variations in mutational processes in colorectal cancer - copy number variants (Mutographs)

  Dataset EGAD00001015487

• De Novo Mutation Rates at the Single-Mutation Resolution in the Human Genome

  We developed a method to measure the origination rates of target mutations of choice and applied it to the HbS and nearby mutations in the human beta-globin (HBB) gene, as well as to the equivalent mutations in the nearly identical delta-globin (HBD) gene in sperm cells from African and European donors. Specifically, after extracting DNA from the sperm of the donors, each sample is enriched for the HbS mutation and nearby mutations by the restriction enzyme Bsu36I, which cleaves the wild-type (WT) sequence CCTGAGG at positions 16–22 of HBB and the homologous positions of HBD while leaving the HbS mutant and other mutants in these positions intact. Next, unique barcodes are attached to the DNA fragments from these Bsu36I-treated samples in order to reduce error by consensus sequencing of copies originating from the same original fragment. To determine how many target WT sequences have been removed (scanned) by Bsu36I digestion and hence to be able to calculate the de novo mutation rate, we run a second reaction in parallel for each donor. This reaction involves the same steps as the former reaction except for digestion by Bsu36I (Bsu36I-untreated). Spiking into the Bsu36I-treated and untreated samples known amounts of mock HBB-like DNA molecules that are fully resistant to Bsu36I digestion allows to calculate in the sequence analysis stage the Bsu36I-enrichment score based on the change in their frequency between the two treatments, which in turn is used to calculate the number of scanned WT sequences. Our results show significant correspondence between de novo mutation rates and past observations of alleles in carriers, showing that mutation rates vary substantially in a mutation-specific manner that contributes to the site frequency spectrum. We also found that the overall point mutation rate is significantly higher in Africans than Europeans in the HBB region studied. Finally, the rate of the 20A>T mutation, called the “HbS mutation” when it appears in HBB, is significantly higher than expected from the genome-wide average for this mutation type. Nine instances were observed in the African HBB ROI, where it is of adaptive significance, representing at least three independent originations, and no instances were observed in the European HBB ROI or in the European or African HBD ROI.12 consented subjects; samples from two subjects were pooled

  Study phs002391

• Assessment of Health-related Quality of Life in Rare Kidney Stones

  The purpose of this study is to learn about Health-related Quality Of Life (HRQoL) in patients enrolled in the Rare Kidney Stone Consortium (RKSC) registries. Quality of life studies look at different aspects of both physical and mental components of people's lives. HRQoL data for people affected by kidney stones are not currently available for people followed over time. All participants enrolled in the RKSC registries will be invited, via email or postal mail, to participate in this study. Health-related quality of life in people with rare kidney stones enrolled in the RKSC registries will be measured. Instruments used in this study are the SF-10 for pediatric participants and SF-36v2 for adult participants. The surveys will be completed online. Participants without a computer or internet access will participate using a paper version of the survey. These surveys will be done at enrollment and annually thereafter. The SF-36v2 includes 36 questions and is estimated to take 15 minutes for its completion, while the SF-10 includes 10 questions and could be completed in 5 minutes. The research questions are: Assessment of HRQoL in patients with rare kidney stones. Comparison of HRQoL results between rare kidney stone formers, general population and other populations with relevant chronic diseases. Comparison of HRQoL results in the same populations affected by different stones and analyzed with attention to the effects of various factors included in the disease registry, such as stone activity, burden of urologic interventions, medication and other treatments. Evaluation of HRQoL and its trends over time in patients undergoing treatment for rare kidney stones. About this study: The plan is to have 400 participants from all four registries take part in this multi-center study. The assessment of your HRQoL will be done annually for 5 years.

  Study phs001770

• PsychENCODE Consortium: Epigenetic and Transcriptional Dysregulation in Autism Spectrum

  Our current understanding of autism spectrum disorders (ASD) delineates a highly heritable, yet etiologically heterogeneous disease. Forward genetic approaches to find disease associated mutations or common variation have been successful and continue to offer considerable power. Yet, given the accumulating evidence for very significant heterogeneity and environmental influences, complementary approaches to classic forward genetics become necessary. Genetic polymorphism and mutation data to date have identified dozens of causal or contributory variants, yet our preliminary data from autism brain suggest that common molecular pathways are involved in a significant subset of cases. This convergence at the tissue level suggests that other mechanisms, specifically epigenetic changes, combined with genetic background, are contributing to such final common pathways. We further tested this hypothesis by taking a comprehensive and integrative genome-wide approach to assessing brain gene-expression, miRNA levels and the related, causal epigenetic mechanisms in ASD etiology. We performed RNA-seq analyses of four cerebral cortical regions and cerebellum from ASD cases and controls, to assess mRNA, miRNA, and splicing isoform regulation. In parallel, we identified key differences in chromatin state and DNA methylation across multiple brain regions in the same ASD and control individuals used in the expression analyses using ChIP-Seq and MeDIP. We assessed the mechanisms by which changes in DNA methylation, histone modification, and DNA sequence contribute to the observed differences in gene expression. This work, which represents an unprecedented effort to unify these often disparate data (usually produced without integration in mind), delineates potential shared molecular pathways in ASD and the underlying mechanism of these differences at the level of miRNA, the chromatin regulatory apparatus, and DNA methylation. The following substudies are part of the PsychENCODE release at dbGaP and offer additional molecular data: PsychENCODE: RNA-Sequencing - SRRM4 Splicing Study phs000872 PsychENCODE: Global Changes in Patterning, Splicing and lncRNAs phs001061 PsychENCODE: Chromatin Contact Map in Fetal Cortical Laminae phs001190 PsychENCODE: Epigenetic Dysregulation in Autism Spectrum Disorder phs001220

  Study phs001022

• National Heart Lung and Blood Institute Exome sequencing in SCID

  Analysis of the molecular etiologies of severe combined immunodeficiency (SCID) has led to important insights into the control of immune cell development. Most cases of SCID result from either X-linked or autosomal recessive inheritance of mutations in a known causative gene. However, in some cases, the molecular etiology remains unclear. To identify the cause of SCID in a patient known to lack the protein tyrosine phosphatase CD45, we utilized single nucleotide polymorphisms (SNP) arrays and whole exome sequencing. The patient's mother was heterozygous for an inactivating mutation in CD45, while the paternal alleles lacked mutations. The patient exhibited a single CD45 mutation identical to the maternal allele. Patient SNP array analysis revealed no change in copy number but loss of heterozygosity for the entire length of chromosome 1 (Chr1), indicating that disease was caused by uniparental disomy (UPD) with isodisomy of the entire maternal Chr1 bearing the CD45 mutation. Non-lymphoid blood cells and other mesoderm and ectoderm-derived tissues retained UPD of the entire maternal Chr1 in this patient who had undergone successful bone marrow transplantation. Exome sequencing revealed mutations in 7 additional genes bearing nonsynonymous SNPs predicted to have deleterious effects. These findings represent the first reported case of SCID caused by UPD and suggest UPD should be considered in SCID and other recessive disorders, especially when the patient appears homozygous for an abnormal gene found in only one parent. Evaluation for alterations in other genes affected by UPD should also be considered in such cases.

  Study phs000479

• Confirmation of a founder effect in a Northern European population (FRL) of a new beta-globin variant: HBB:c.23_26dup (codons 8/9 (+AGAA))

  Beta-thalassemia is a genetic disease caused by a defect in the production of the beta-like globin chain. More than 200 known different variants can lead to the disease and are mainly found in populations that have been exposed to malaria parasites. We recently described a duplication of 4 nucleotides in the first exon of beta-globin gene in several families of patients living in Nord-Pas-de-Calais (France). Using the genotypes at 12 microsatellite markers surrounding the beta-globin gene of four unrelated variant carriers plus an additional one recently discovered, we found that they shared a common haplotype indicating a founder effect that was estimated to have taken place 225 years ago (9 generations). In order to determine whether this variant arose in this region of Northern-Europe or was introduced by migrants from regions of the world where thalassemia is endemic, we genotyped the first 4 unrelated variant carriers and 32 controls from Nord-Pas-de-Calais for 97 European ancestry informative markers (EAIMs). Using these EAIMs and comparing with population reference panels, we demonstrated that the variant carriers were very similar to the controls and were closer to North European populations than to South European or Middle-East populations. Rare beta-thalassemia variants have already been described in patients sampled in non-endemic regions but it is the first proof of a founder effect in Northern Europe. The new genetic panel FRL is under registration in EGA.

  Study EGAS00001000980

• Identification and Targeting of Inflammatory Macrophage-Fibroblast Crosstalk in Rheumatoid Arthritis

  Macrophages tailor their function according to the signals found in tissue microenvironments, assuming a wide spectrum of phenotypes. A detailed understanding of macrophage phenotypes in human tissues is limited. Using single-cell RNA sequencing, we defined distinct macrophage subsets in the joints of patients with the autoimmune disease rheumatoid arthritis (RA), which affects ~1% of the population. The subset we refer to as HBEGF+ inflammatory macrophages is enriched in RA tissues and is shaped by resident fibroblasts and the cytokine tumor necrosis factor (TNF). These macrophages promoted fibroblast invasiveness in an epidermal growth factor receptor-dependent manner, indicating that intercellular cross-talk in this inflamed setting reshapes both cell types and contributes to fibroblast-mediated joint destruction. In an ex vivo synovial tissue assay, most medications used to treat RA patients targeted HBEGF+ inflammatory macrophages; however, in some cases, redirecting them into a state is not expected to resolve inflammation. These data highlight how advances in our understanding of chronically inflamed human tissues and the effects of medications therein can be achieved by studies on local macrophage phenotypes and intercellular interactions. Reprinted from Kuo, Ding et al., Science Translational Medicine 2019, PMID: 31068444, with permission from American Association for the Advancement of Science.

  Study phs001340

• Joint-Specific TF Regulation in RA

  The mechanisms responsible for the distribution and severity of joint involvement in rheumatoid arthritis (RA) are not known. To explore whether site-specific fibroblast-like synoviocyte (FLS) biology might be associated with location-specific synovitis and explain the predilection for hand (wrist/metacarpal phalangeal joints) involvement in RA, we generated bulk, whole-genome transcriptomic and chromatin accessibility data from FLS. Samples were matched in age, sex, and were homogeneous in that all had significant joint damage with longstanding disease requiring surgical intervention. Analysis revealed joint-specific patterns of FLS phenotypes, with proliferative, migratory, proinflammatory, and matrix-degrading characteristics observed in resting FLS derived from the hand joints compared with hip or knee. TNF-stimulation amplified these differences, with greater enrichment of proinflammatory and proliferative genes in hand FLS compared with hip and knee FLS. Hand FLS also had the greatest expression of markers associated with an ‘activated' state relative to the ‘resting' state, with the greatest cytokine and MMP expression in TNF-stimulated hand FLS. Predicted differences in proliferation and migration were biologically validated with hand FLS exhibiting greater migration and cell growth than hip or knee FLS. Distinctive joint-specific FLS biology associated with a more aggressive inflammatory response might contribute to the distribution and severity of joint involvement in RA.

  Study phs003633

• Tumor-derived exosomes modulate PD-L1 expression in monocytes

  In chronic lymphocytic leukemia (CLL), monocytes and macrophages are skewed toward protumorigenic phenotypes, including the release of tumor-supportive cytokines and the expression of immunosuppressive molecules such as programmed cell death 1 ligand 1 (PD-L1). To understand the mechanism driving protumorigenic skewing in CLL, we evaluated the role of tumor cell–derived exosomes in the cross-talk with monocytes. We carried out RNA sequencing and proteome analyses of CLL-derived exosomes and identified noncoding Y RNA hY4 as a highly abundant RNA species that is enriched in exosomes from plasma of CLL patients compared with healthy donor samples. Transfer of CLL-derived exosomes or hY4 alone to monocytes resulted in key CLL-associated phenotypes, including the release of cytokines, such as C-C motif chemokine ligand 2 (CCL2), CCL4, and interleukin-6, and the expression of PD-L1. These responses were abolished in Toll-like receptor 7 (TLR7)–deficient monocytes, suggesting exosomal hY4 as a driver of TLR7 signaling. Pharmacologic inhibition of endosomal TLR signaling resulted in a substantially reduced activation of monocytes in vitro and attenuated CLL development in vivo. Our results indicate that exosome-mediated transfer of noncoding RNAs to monocytes contributes to cancer-related inflammation and concurrent immune escape via PD-L1 expression.

  Study EGAS00001002377