Non-coding RNA expression in colorectal cancer
Ontology highlight
ABSTRACT:
ORGANISM(S): Homo sapiens
SUBMITTER: Morten Nielsen
PROVIDER: E-GEOD-76713 | biostudies-arrayexpress |
REPOSITORIES: biostudies-arrayexpress
Similar Datasets
Project description:Expression was measured in 113 colorectal cancer samples using a costumized array.
2016-01-12 | GSE76713 | GEO
Project description:Purpose: mRNA translation into protein is highly regulated, but the role of mRNA isoforms, noncoding RNAs (ncRNAs), and genetic variants has yet to be systematically studied. Using high-throughput sequencing (RNA-seq), we have measured cellular levels of mRNAs and ncRNAs, and their isoforms, in lymphoblast cell lines (LCL) and in polysomal fractions, the latter shown to yield strong correlations of mRNAs with expressed protein levels. Analysis of allelic RNA ratios at heterozygous SNPs served to reveal genetic factors in ribosomal loading. Methods: RNA-seq was performed on cytosolic extracts and polysomal fractions (3 ribosomes or more) from three lymphoblastoid cell lines. As each RNA fraction was amplified (NuGen kit), and relative contributions from various RNA classes differed between cytosol and polysomes, the fraction of any given RNA species loaded onto polysomes was difficult to quantitate. Therefore, we focused on relative recovery of the various RNA classes and rank order of single RNAs compared to total RNA. Results: RNA-seq of coding and non-coding RNAs (including microRNAs) in three LCLs revealed significant differences in polysomal loading of individual RNAs and isoforms, and between RNA classes. Moreover, correlated distribution between protein-coding and non-coding RNAs suggests possible interactions between them. Allele-selective RNA recruitment revealed strong genetic influence on polysomal loading for multiple RNAs. Allelic effects can be attributed to generation of different RNA isoforms before polysomal loading or to differential loading onto polysomes, the latter defining a direct genetic effect on translation. Several variants and genes identified by this approach are also associated with RNA expression and clinical phenotypes in various databases. Conclusions: These results provide a novel approach using complete transcriptome RNA-seq to study polysomal RNA recruitment and regulatory variants affecting protein translation. cells from 3 samples were grown to 5x105 cells/mL density in T75 tissue culture flask and harvested, total RNA and polysome bound RNA was sequenced by Ion Proton
2015-06-30 | E-GEOD-66135 | biostudies-arrayexpress
Project description:Despite identification of major genes and pathways involved in development of colorectal cancer (CRC) it became obvious that several steps in these pathways might be bypassed by other yet unknown genetic events that lead towards CRC. To improve our understanding of the genetic mechanisms of CRC development we used microarrays to identify novel genes involved in development of CRC. In order to identify possible novel genes involved in the development of colorectal cancer we analysed the expression profile of 16 colorectal cancers. We used dual color approach. Tumour tissue was labeled with Cy5 and corresponding normal tissue was labeled with Cy3. Each array contained at least 4 replicate spots for each gene analysed. Expression was obtained by calculating median from replicate spots. Genes not present in at least 100% of all samples were filtered out. Median value for each gene from 16 arrays was calculated.
2010-06-20 | E-GEOD-14010 | biostudies-arrayexpress
Project description:Canonical Wnt signaling output is mediated by β-catenin, which interacts with LEF/TCF transcription factors and recruits a general transcriptional activation complex to its C-terminus. Its N-terminus binds BCL9/9L proteins, which bind co-activators that in mammals contribute to fine-tuning the transcriptional output. We found that a BCL9/9L-dependent gene expression signature was strongly associated with patient outcome in colorectal cancer and that stem cell and mesenchymal genes determine its prognostic value. Abrogating BCL9/9L-β-catenin signaling in independent mouse colorectal cancer models resulted in virtual loss of these traits, and oncogenic intestinal organoids lacking BCL9/9L proteins proved no longer tumorigenic. Our findings suggest that the BCL9/9L arm of Wnt-β-catenin signaling sustains a stemness-to-differentiation equilibrium in colorectal cancer, which critically affects disease outcome. Mutational activation of the Wnt pathway is a key oncogenic event in colorectal cancer. Targeting the pathway downstream of activating mutations is challenging, and the therapeutic window is limited by intestinal toxicity. Contrasting with phenotypes caused by inactivating key Wnt pathway components, ablation of BCL9/9L proteins in adult mice indicated that they were dispensable for intestinal homeostasis, consistent with their role in tuning transcription. Cancer stem cells are increasingly recognized as responsible for tumor recurrence. The correlation between stemness traits in colorectal cancer models and BCL9/9L-β-catenin signaling suggests that high Wnt signaling output is required for their maintenance. Our findings suggest that pruning Wnt-β-catenin signaling might be well tolerated and prove sufficient for trimming stemness traits and improving disease outcome. Examination of Bcl9/9l-knockout versus wild-type transcriptome in murine AOM-DSS tumors, APC-Kras tumors and healthy colocyte extracts.
2015-11-08 | E-GEOD-60837 | biostudies-arrayexpress
Project description:Listeria monocytogenes is a human, food-borne pathogen. Genomic comparisons between L. monocytogenes and Listeria innocua, a closely related non-pathogenic species, were pivotal in the identification of protein coding genes essential for virulence. However, no comprehensive comparison has focused on the non-coding genome. We used strand-specific cDNA sequencing to produce genome-wide transcription start site (TSS) maps for both organisms, and developed a publicly available integrative browser to visualize and analyze both transcriptomes in different growth conditions and genetic backgrounds. Our data revealed conservation across most transcripts, but significant divergence between the species in a subset of non-coding RNAs. In L. monocytogenes we identified 113 sRNAs and 70 asRNAs, significantly increasing the repertoire of non coding RNAs in this species. Remarkably, we identified a class of long antisense transcripts (lasRNAs) that overlap one gene while also serving as the 5M-bM-^@M-^Y UTR of the adjacent divergent gene. Experimental evidence suggests that lasRNAs transcription inhibits expression of one operon while activating the expression of another. Such lasRNA/operon structure, termed "excludon", might represent a novel form of regulation in bacteria. Construction of consensus TSS-maps in Listeria monocytogenes and Listeria innocua by applying 5'-end sequencing on samples in different conditions and genetic backgrounds.
2012-05-01 | E-GEOD-36060 | biostudies-arrayexpress
Project description:PIWI-interacting RNAs (piRNAs) mediate transposable element (TE) silencing at the transcriptional or post-transcriptional level in animal gonads. In the Drosophila ovary, Piwiâ??piRNA complexes (Piwiâ??piRISCs) repress TE transcription by modifying the chromatin state, such as H3K9me3 marks. Here, we demonstrate that Piwi physically interacts with linker histone H1. Depletion of Piwi decreases H1 density on target loci, leading to TE derepression. Loss of H1 results in gain of chromatin accessibility at target loci without affecting H3K9me3 and heterochromatin protein 1a (HP1a) density at the same loci. Piwi-mediated TE silencing also requires HP1a by regulating chromatin accessibility through its association with target loci. Thus, Piwiâ??piRISCs require both H1 and HP1a to repress TEs, and the silencing is correlated with the state of chromatin formation rather than H3K9me3 marks. These findings suggest that Piwiâ??piRISCs regulate the interaction of chromatin components with target loci to maintain silencing of the TE state through the modulation of chromatin accessibility. RNA levels, H1 and H3K9me3 occupancy, chromatin accessibility, and Piwi-associated small RNA levels in ovarian somatic cells (OSC) depleted of piRNA pathway components and H1.
2016-06-30 | E-GEOD-81434 | biostudies-arrayexpress
Project description:To measure global gene expression in primary advanced colorectal cancer patients who have undergone fluorouracil, leucovorin and oxaliplatin (FOLFOX4) chemotherapy and screen valuable biomarkers to predict the effects of chemotherapy Samples from primary advanced colorectal cancer patients were collected. The effects of chemotherapy were evaluated, and patients were divided into an experimental group and a control group. All patients underwent standard FOLFOX4 regimen chemotherapy in four cycles after signing the chemotherapy agreement; subsequently, they were evaluated in accordance with the Response Evaluation Criteria In Solid Tumors (RECIST).Each samplewas collected immediately following resection. Each sample was divided in half: one half was fixed in formalin and embedded in paraffin; the other half floated in ice-cold phosphate-buffered saline and was stored in liquid nitrogen until total RNA extraction. CEL files available for only 16/30 samples. Remaining CEL files have been lost.
2015-12-31 | E-GEOD-69657 | biostudies-arrayexpress
Project description:Microsatellite instability (MSI), caused by defective mismatch repair, is observed in a subset of colorectal cancers (CRCs). We evaluated somatic mutations in microsatellite repeats of genes chosen based on reduced expression in MSI CRC and existence of a coding mononucleotide repeat. Expression profiling of 34 MSI colorectal cancers and 15 normal colonic mucosas was performed in 2002. Comparison of malignant and healthy tissue.
2011-03-01 | E-GEOD-24514 | biostudies-arrayexpress
Project description:MicroRNAs (miRNAs) represent a conserved class of small non-coding RNAs that are found in all higher eukaryotes as well as some DNA viruses. MiRNAs are 20-25 nucleotides (nt) in length and have important regulatory functions in biological processes such as embryonic development, cell differentiation, hormone secretion or metabolism. Furthermore, miRNAs have been implicated in the pathology of various diseases including cancer. MiRNA expression profiles not only classify different types of cancer but also may even help to characterize distinct tumor stages, therefore constituting a valuable tool for prognosis. Here we report the miRNA profile of Epstein-Barr Virus (EBV)-positive nasopharyngeal carcinoma (NPC) tissue samples characterized by cloning and sequencing. We find that all EBV miRNAs from the BART region are expressed in NPC tissues whereas ebv-miRNAs from the BHRF1 region are not found. Moreover, we identify two novel EBV miRNA genes originating from the BART region that have not been found in other tissues or cell lines before. We also identify three new human miRNAs, which might be specific for nasopharyngeal tissues. We further show that a number of different cellular miRNAs are upor down-regulated in NPC tissues compared to control tissue including miR-15a and miR-16. We find that the tumor suppressor BRCA-1 is a target of miR-15a as well as miR-16 suggesting a miRNA role in NPC pathogenesis. 2 pairs of NPC and control tissues from 2 patients (4 samples in total) were examined.
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Project description:The objective of this study was to measure copy number alterations in a panel of 15 CRC cell lines and relate them to treatment sensitivity. Assessment of copy number variations in a panel of 15 colorectal cancer cell lines
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