Comparative analysis of circular RNA landscapes in primary and secondary brain tumors
Ontology highlight
ABSTRACT:
ORGANISM(S): Homo sapiens
PROVIDER: GSE314175 | GEO | 2026/05/22
REPOSITORIES: GEO
Similar Datasets
Project description:Comparative analysis of circular RNA landscapes in primary and secondary brain tumors
| PRJNA1390216 | ENA
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:MicroRNAs (miRNAs) are small (21-25 nucleotide in length) non-coding RNA molecules that negatively regulate protein expression. They are linked to cancer development and maintenance. In this work, studying gene expression profiles of 340 mammalian miRNAs with DNA microarrays, we selected 10 miRNAs gene features able to distinguish primary from secondary glioblastoma type; furthermore we verified that miR-21 and miR-155 up-regulatation seems to characterize the glioblastoma tumour state since it was found up-regulated in all samples analyzed compared to adult brain noneoplastic tissue. Since miR-21 function in glioblastoma cells was addressed previously we concentrated our efforts on miR-155 function. We found that miR-155 levels were markedly elevated both in primary and secondary glioblastomas tumours, in glioblastoma cell cultures and in 4 glioblastoma cell lines (U87, A172, LN229, and LN308) compared with adult brain tissue, CHP212-neuroblastoma cell lines and DAOY-1-medulloblastoma cell line. Since one of the miR-155 target was gamma-aminobutyric acid (GABA) A receptor (GABRA1) we verified if there was a relation between miR-155 up-regulation and GABRA1 expression. We demonstrated that, in cultured glioblastoma cells, knockdown of miR-155, which lower miR-155 expression to normal level, restore the normal expression of the gamma-aminobutyric acid (GABA) A receptor (GABRA1), making glioblastoma cells responsive to GABA cell cycle inhibiting signals. Our data suggest that aberrantly over-expressed miR-155 contribute to the malignant phenotype of the glioblastoma cells, promoting their unlimited growth. Keywords: miRNA expression profile We studied the expression profiles of 340 miRNAs in 97 glioblastoma tissues, of which 66 were primary glioblastomas and 27 were secondary glioblastomas. We have 66 replicates of primary glioblastoma and 27 replicates of secondary glioblastoma, each hybridized with the respective adult non-neoplastic brain tissue as a control.
2010-05-17 | E-GEOD-13030 | biostudies-arrayexpress
Project description:The distinction between primary and secondary ovarian tumors may be challenging for pathologists. We performed transcriptomic analysis in order to discriminate between primary ovarian tumors and ovarian metastases after primary breast cancer. We performed genomic analysis on tumor paired samples (breast/ovary) in order to know if genomic profiles could help for the discrimination of primary ovarian tumors and ovarian metastases after primary breast cancer.
2010-04-14 | GSE20565 | GEO
Project description:Here we profile the expression of circRNA in 6 different brain tissues at up to 6 different time-points during fetal porcine development, constituting the first report of circRNA in a large animal. An unbiased analysis reveals a highly complex regulation pattern of thousands of circular RNAs, with a distinct spatio-temporal expression profile. The amount and complexity of the circRNA expression was most pronounced in cortex day 60 from gestation. Here we find 4,634 unique circRNAs expressed from 2,195 genes out of a total of 13,854 expressed genes. These data demonstrate that circRNAs are highly abundant and dynamically expressed in a spatio-temporally manner in porcine fetal brain, suggesting important functions during mammalian brain development.
2015-10-06 | GSE71832 | GEO
Project description:Microarray analysis was used to identify differential circRNA expression profiles between breast cancer cell lines derived from primary tumors and metastatic lesions. Furthermore, the influence of differentiation- and stemness-inducing culture conditions on the circRNA landscape was assessed.
2026-05-22 | GSE302027 | GEO
Project description:This study employs a label-free quantitative proteomics approach to analyze protein expression profiles in lung and brain tissues harvested from an established LIR-induced secondary brain injury model.
2026-07-19 | PXD081347 |
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.
2015-04-24 | GSE65926 | GEO
Project description:Circular RNAs (circRNAs) represent a class of endogenous, non-coding RNAs that are formed when exons back splice to each other and that are both highly conserved and pervasively expressed in the mammalian brain. The goal of this study was thus to systematically identify and characterize circRNA expression and as well as to evaluate the predicted impact on regulatory networks in five functionally distinct cortical regions of healthy aged human brain - cerebellum (BC), inferior parietal lobe (IPL), middle temporal gyrus (MTG), occipital cortex (OC) and superior frontal gyrus (SGF).
| EGAS00001003128 | EGA
Project description:Recent studies have identified circular RNAs (circRNAs) expressed from the Epstein-Barr virus (EBV) and Kaposi’s sarcoma herpesvirus (KSHV) human DNA tu- mor viruses. To gain initial insights into the potential relevance of EBV circRNAs in virus biology and disease, we assessed the circRNAome of the interspecies homologue rhesus macaque lymphocryptovirus (rLCV) in a naturally occurring lymphoma from a simian immunodeficiency virus (SIV)-infected rhesus macaque. This analysis revealed rLCV orthologues of the latency-associated EBV circular RNAs circRPMS1_E4_E3a and circEBNA_U. Also identified in two samples displaying unusually high lytic gene expres- sion was a novel rLCV circRNA that contains both conserved and rLCV-specific RPMS1 exons and whose backsplice junctions flank an rLCV lytic origin of replication (OriLyt). Analysis of a lytic infection model for the murid herpesvirus 68 (MHV68) rhadinovirus identified a cluster of circRNAs near an MHV68 lytic origin of replication, with the most abundant of these, circM11_ORF69, spanning the OriLyt. Lastly, analysis of KSHV la- tency and reactivation models revealed the latency associated circRNA originating from the vIRF4 gene as the predominant viral circRNA. Together, the results of this study broaden our appreciation for circRNA repertoires in the Lymphocryptovirus and Rhadinovirus genera of gammaherpesviruses and provide evolutionary support for vi- ral circRNA functions in latency and viral replication.
2019-01-07 | GSE124711 | GEO