CircRNA expression and characterization in multiple sclerosis patients and controls
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ABSTRACT:
ORGANISM(S): Homo sapiens
PROVIDER: GSE161196 | GEO | 2022/12/01
REPOSITORIES: GEO
Similar Datasets
Project description:Circular RNAs (circRNAs) are covalently closed non-coding RNAs lacking the 5’ cap and the poly-A tail. Nevertheless, it has been demonstrated that certain circRNAs can undergo active translation. Therefore, aberrantly expressed circRNAs in human cancers could be an unexplored source of tumor-specific antigens, potentially mediating anti-tumor T cell responses. This study presents an immunopeptidomics workflow with a specific focus on generating a circRNA-specific protein fasta reference. The main goal of this workflow is to streamline the process of identifying and validating human leukocyte antigen (HLA) bound peptides potentially originating from circRNAs. We increased the analytical stringency of our workflow by retaining peptides identified independently by two mass spectrometry search engines and/or by applying a group-specific FDR for canonical-derived and circRNA-derived peptides. A subset of circRNA-derived peptides specifically encoded by the region spanning the back-splice junction (BSJ) were validated with targeted MS, and with direct Sanger sequencing of the respective source transcripts. Our workflow identified 54 unique BSJ-spanning circRNA-derived peptides in the immunopeptidome of melanoma and lung cancer samples. Our novel approach enlarges the catalog of source proteins that can be explored for immunotherapy.
2024-03-20 | PXD043989 | Pride
Project description:Circular RNAs (circRNAs), a noncoding RNA class originating from alternative splicing, are highly abundant in neural tissues and were shown to regulate gene expression e.g. by interacting with microRNAs and RNA-binding proteins. Neuroblastoma is an embryonal neoplasia, which arises from undifferentiated neural crest cells. Here, we aimed to explore, whether circRNAs influence the pathogenesis of high-risk neuroblastoma. We performed whole-transcriptome sequencing of 104 primary neuroblastoma samples of all risk-groups and identified 5,203 unique circRNAs involving 2,302 genes. Candidate circRNA expression did not correlate with host gene expression, indicating independent regulatory mechanisms. circRNAs were significantly downregulated in the MYCN-amplified high-risk tumors. These findings were independently reproduced in a tetracycline-inducible MYCN-overexpression system based on a non MYCN-amplified neuroblastoma cell line, suggesting that MYCN drives this global circRNA repression. We identified the RNA helicase DHX9 as a mediator of this global suppressive effect of MYCN on circRNAs. Comparing our RNA sequencing data with other cancers and controls revealed a circRNA subset specifically upregulated in neuroblastoma that included a circRNA derived from the ARID1A tumor suppressor gene. Specific circARID1A knockdown resulted in reduced proliferation, cell numbers and viability, prompted apoptosis and induced a differentiated phenotype. Neither knockdown, nor overexpression of circARID1A influenced ARID1A mRNA and protein levels significantly. To dissect the potential mode of function, we performed a pulldown assay with subsequent mass spectrometry. We identified the RNA-binding protein KHSRP as an interaction partner that participates in the mechanism of action of circARID1A. In summary, this study highlights an important role of circRNAs in neuroblastoma biology and may establish this RNA class as a future therapeutic target and biomarker.
2023-04-06 | PXD026053 | Pride
Project description:Arraystar Human circRNA Microarray is designed for the global profiling of human circRNAs. In this study, we applied a circRNA microarray to screen the potential biomarker for HCC. 20 samples extracted from plasma samples including HCC group before operation, and after operation, CH group and control group. Each group contained five samples.
2021-03-02 | E-MTAB-8799 | biostudies-arrayexpress
Project description:Background and aim: The disease course and clinical phenotype in multiple sclerosis (MS) are highly variable and therefore, biomarkers are needed. Studies have shown a dysregulation in the coding and non-coding RNAs and proposed some as biomarkers. However, still none of them have reached the clinical practice. Recently, circular RNAs (circRNAs) have emerged as new players in the transcriptome that hold a great potential as biomarkers in several diseases. In this study we have performed a RNASeq profiling of patients (N=50) and healthy controls' (N=20) leukocytes in order to characterize their linear and circular transcriptomes with the final aim of finding some new potential biomarkers. Methods: Differential expression analysis was performed by DESeq and circRNA candidates were studied in a second cohort (70MS and 46HC) by RT-qPCR and in paired samples drawn during the relapse and remission phases (20 patients). Results: Among the differentially expressed circRNAs, the 96.1% is are upregulated in patients compared to controls, but similar circRNA profiles are found between MS types. The same upregulation trend was observed in females but not in males or in the linear transcriptome. The upregulation of 6 circRNAs was validated and a change in their expression was found between relapse and remission. The 6 circRNAs showed a good performance to discriminate patients from HC with a combined AUC of 0.852. Conclusion: There is global, specific and sex dependent increase of circRNA expression in MS and 6 circRNAs are proposed as potential biomarkers.
2020-10-09 | GSE159225 | GEO
Project description:Circular RNAs (circRNAs) are a large class of animal RNAs. To investigate possible circRNA functions, it is important to understand circRNA biogenesis. Besides human Alu repeats, sequence features that promote exon circularization are largely unknown. We experimentally identified new circRNAs in C. elegans. Reverse complementary sequences between introns bracketing circRNAs were significantly enriched compared to linear controls. By scoring the presence of reverse complementary sequences in human introns we predicted and experimentally validated novel circRNAs. We show that introns bracketing circRNAs are highly enriched in RNA editing or hyper-editing events. Knockdown of the double-strand RNA editing ADAR1 enzyme significantly and specifically up-regulated circRNA expression. Together, our data support a model of animal circRNA biogenesis in which competing RNA:RNA interactions of introns form larger structures which promote circularization of embedded exons, while ADAR1 antagonizes circRNA expression by melting stems within these interactions. Thus, we assign a new function to ADAR1. Examination of 12 samples in different stages of C.elegans development.
2015-01-06 | E-GEOD-63823 | biostudies-arrayexpress
Project description:Circular RNAs are a class of non-coding RNAs mostly generated by back-splicing RNA transcripts of protein-coding gene loci. In difference to canoncial splicing, back-splicing ligates downstream splice donor site with an upstream splice acceptor generating a covalently closed circular RNA. CircRNAs have been reported to influence cellular functions by acting as miRNA sponges, regulation of host gene transcription or by protein interactions. The circRNA cZNF292 has been previously reported to be regulated under hypoxia and to influence endothelial cell angiogenesis and functions. The present data set aims to identfy protein interactions partners of cZNF292 in endothelial cells to further characterize the mechanism of action of cZNF292. Dataset comprises 8 replicates of proteins identified after biotin-based 2'O-Me RNA antisense affinity purification of the circRNA cZNF292 from HUVEC (human umbilical vein endothelial cell) lysates compared to a control probe dataset. Purification was performed without cross-linking under low salt and mild detergent conditions.
2022-11-29 | PXD029794 | Pride
Project description:Objective Circular RNAs (circRNAs) are covalently closed, endogenous non-coding RNAs. CircRNAs play a vital role in liver diseases, acting as microRNA (miRNA) sponges. However, the angiogenic role of circRNA remains unknown in liver fibrosis and is the focus of this study. Methods Liver fibrosis was induced by thioacetamide (TAA), or carbon tetrachloride (CCl4) in mice. CircRNA-microarray, AGO2-RNA immunoprecipitation (RIP), and RNA-seq were utilized to explore the hepatic circRNAs profile. The qPCR and PCR-gel electrophoresis analysis were used to investigate the characterization of circRNA-007371. Liver tissues and EMOA murine endothelial cells were used to verify the angiogenic mechanism of circRNA-007371. Results The increased collagen deposition, pseudolobule formation, and angiogenesis were observed in murine liver induced by TAA and CCl4. CircRNA-microarray in TAA-induced fibrotic murine liver indicated that the expression of circRNA-007371 was up-regulated. Moreover, AGO2-RIP and PCR analysis showed that circRNA-007371 had the characterization of circRNAs and played a role as competing endogenous RNAs (ceRNA) sponging miR-200a. In vitro, circRNA-007371 promoted the ability of migration, growth, and blood vessel formation in EMOA murine endothelial cells using wound healing and tube formation assay. The AGO2-RIP and RNA-sequencing analysis in overexpression circRNA-007371 EMOA murine endothelial cells demonstrated that circRNA-007371 upregulates the stromal antigen 1 (Stag1) via spouse of miR-200a and HIF-1 signaling pathway might participate in the angiogenesis. Conclusions This study discovers that circRNA-007371, a novel ceRNA, is up-regulated, and enhances the angiogenesis via angiocrine role to regulate the STAG1-miR-200a-5p signaling pathway in liver fibrosis.
2023-06-28 | GSE218574 | GEO
Project description:Circular RNAs (circRNAs) are an endogenous class of animal RNAs. Despite their abundance, their function and expression in the nervous system are unknown. Therefore, we sequenced RNA from different brain regions, primary neurons, isolated synapses, as well as during neuronal differentiation. Using these and other available data, we discovered and analyzed thousands of neuronal human and mouse circRNAs. circRNAs were extraordinarily enriched in the mammalian brain, well conserved in sequence, often expressed as circRNAs in both human and mouse, and sometimes even detected in Drosophila brains. circRNAs were overall upregulated during neuronal differentiation, highly enriched in synapses, and often differentially expressed compared to their mRNA isoforms. circRNA expression correlated negatively with expression of the RNA-editing enzyme ADAR1. Knockdown of ADAR1 induced elevated circRNA expression. Together, we provide a circRNA brain expression atlas and evidence for important circRNA functions and values as biomarkers. To assess circRNA expression in mammalian brain, we sequenced and analyzed mouse brain regions (hippocampus, cerebellum, prefrontal cortex and olfactory bulb), various neuronal differentiation (mouse P19 and human SH-SY5Y cells) and maturation (mouse cortical neurons) stages, and subcellular compartments in mouse (synaptoneurosomal fraction, cytoplasmic fraction, whole brain lysate).
2015-04-24 | E-GEOD-65926 | biostudies-arrayexpress
Project description:Atrial fibrillation (AF) is the most common irregular heart rhythm which influence approximately 1–2% of the general population. As a potential factor for ischemic stroke, AF could also cause heart failure. The mechanisms behind AF pathogenesis are complex and remains elusive. As a new category of non-coding RNAs (ncRNAs), circular RNAs (circRNAs) have been known as the key of developmental processes, regulation of cell function, pathogenesis of heart diseases and pathological responses which could provide novel sight into the pathogenesis of AF. circRNAs function as modulators of microRNAs in cardiac disease. To investigate the regulatory mechanism of circRNA in atrial fibrillation, especially the complex interactions among circRNA, microRNA and mRNA, we collected the heart tissues from three AF patients and three healthy controls and profiled their circRNA expressions with circRNA Microarray. The differentially expressed circRNAs were identified and the biological functions of their interaction microRNAs and mRNAs were analyzed. Our results provided novel insights of the circRNA roles in atrial fibrillation and proposed highly possible interaction mechanisms among circRNAs, microRNAs and mRNAs.
2019-04-06 | GSE129409 | GEO
Project description:Circular RNAs (circRNAs) are a recently discovered non-coding RNA isoform capable of regulating neurological disease incidence. The present study was designed to characterize the circRNA expression profiles present in large-artery atherosclerosis (LAA)-type acute ischemic stroke patients. Using a RNA-seq approach, we characterized circRNA expression profiles in 5 LAA-stroke patients and 4 controls. We identified 182 and 176 circRNAs that were up- and down-regulated, respectively, in LAA-stroke patients relative to controls. Enrichment analyses suggested these differentially expressed circRNAs to primarily be associated with chromatin modification, autophagy, platelet activation, and neural precursor cell proliferation.
2021-12-31 | GSE161913 | GEO