Ontology highlight
ABSTRACT:
PROVIDER: PRJNA758998 | ENA |
REPOSITORIES: ENA
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Project description:Expression profiling was used to identify genes differentially expressed in MSS (microsatellite stable) and MSI (microsatellite unstable) colon cancer cell lines. Data submitted in support of manuscript entitled Villin expression is frequently lost in poorly differentiated colon cancer, Diego Arango, Sheren Al-Obaidi, David S. Williams, Jose Dopeso, Rocco Mazzolini, Georgia Corner, Do-Sun Byun, Carmel Murone, Lars Tögel, Nikolajs Zeps, Lauri A. Aaltonen, Barry Iacopetta and John M. Mariadason, American Journal of Pathology, 2012. 5 microsatellite stable (MSS) and 5 microsatellite unstable (MSI) colon cancer cell lines profiled. Each cell line grown and arrayed in duplicate, and the duplicates averaged for each cell line before calculating means for MSS and MSI lines.
2012-02-07 | E-GEOD-35566 | biostudies-arrayexpress
Project description:Among the examined genes, none of genes associated with high frequency microsatellite instability (MSI-H) in the panel was mutated (MLH1, MSH2, POLE). In addition, clustering analyses based on RNA-seq data indicated that expression profiles of the spheroids were more similar to colon cancer cells in the CMS-2 and CMS-3 category than those in the MSI-H-related CMS-1. These data suggested that all the examined spheroids were associated with microsatellite stable (MSS) phenotype.
2021-02-25 | GSE167395 | GEO
Project description:Colorectal cancer, one of the most frequent types of malignancy in the Western world, develops through a multi-step process. The main pathways establishing transformation of normal mucosa to invasive carcinoma include chromosomal instability (CIN), microsatellite instability (MSI) or epigenetic silencing through the CpG Island Methylator Phenotype (CIMP). These pathways have distinct clinical, pathological and genetic characteristics. In general, altered cell surface glycosylation has been linked to colorectal cancer progression, however the impact of MSI-specific pathways on the glycosylation machinery of MSI colon cancer cells has not been investigated yet. In a recent study (Patsos et al., 2009) we have shown that MSI-specific mutations induce marked alterations in cell surface glycosylation, indicating specific changes in the expression of glyco-genes. Therefore the purpose of our experiment is to define these changes by glyco-gene chip analysis. Biallelic mutational inactivation of MSI target genes is believed to drive MSI tumorigenesis. TGFBR2, ACVR2 and AIM2 are among the most frequently mutated genes in MSI colorectal adenomas and carcinomas and functional studies indicate their contribution to MSI-carcinogenesis. A first general screening approach by lectin FACS analysis indicated a correlation between functional inactivation of these genes and cell surface glycosylation of the MSI colon cell line HCT116 (Patsos et al., 2009). For detailed analysis of the altered glycosylation pattern and the underlying molecular mechanisms we have established HCT116 double stable transfectants that allow doxycycline-inducible expression of the three MSI target genes TGFBR2, ACVR2 and AIM2 in a reversible manner. Thus we can experimentally control the expression of the MSI-genes and analyze short and long-term effects on different cell functions, including glycosylation. From the application of the glyco-gene chip for analysis of the transfectants we expect to gain seminal information on the influence of MSI-target genes on glycan expression and function in MSI tumor cells. Correlating loss-of-function of MSI target genes not yet linked with glycosylation to the regulation of the glycophenotype is a novel approach to investigate the glycobiology of tumor cells. In addition it is also suitable to detect new MSI-(glyco)markers for clinical applications, including diagnostic tumor markers and specific targets for immunotherapies.
2011-09-05 | E-GEOD-31927 | biostudies-arrayexpress
Project description:Inhibition of the nonsense mediated decay (NMD) mechanism in cells results in stabilization of transcripts carrying premature translation termination codons. A strategy referred to as gene indentification by NMD inhibition (GINI) has been proposed to identify genes carrying nonsense mutations (Noensie & Dietz, 2001). Genes containing frameshift mutations in colon cancer cell line have been identifying mutatnt genes using GINI, we have now further improved the strategy. In this approach, inhibition of NMD with emetine is complemented with inhibiting NMD by blocking the phosphorylation of the hUpf1 protein with caffeine. In addition, to enhance the GINI strategy, comparing mRNA level alterations produced by inhibiting transcription alone or inhbiiting transcription together with NMD following caffeine pretreatment were used for the efficient identification of false positives produced as a result of stress response to NMD inhibition. To demonstrate the improved efficiency of this approach, we analyzed colon cancer cell lines showing microstellite instability. Bi-allelic inactivating mutations were found in the FXR1, SEC1L1, NCOR1, BAT3, PHD14, ZNF294, C190ORF5 genes as well as genes coding for proteins with yet unknown functions. Experiment Overall Design: Using GINI2 as a method of identifying novel biallelic truncating mutations in MSI+ colon cancer cells, various treatment conditions were applied to cultured colon cancer cell lines LS180 (MSI+) and SW480 (MSI-) and gene expression profiling was measured using Affymetrix GeneChip U133 Plus 2 arrays.
2008-06-13 | E-GEOD-5486 | biostudies-arrayexpress
Project description:Background. Colorectal cancer develops through two main genetic instability pathways characterized by distinct pathologic features and clinical outcome. Results. We investigated colon cancer samples (23 characterized by microsatellite stability, MSS, and 16 by high microsatellite instability, MSI-H) for genome-wide expression of microRNA (miRNA) and mRNA. Based on combined miRNA and mRNA gene expression, a molecular signature consisting of twenty seven differentially expressed genes, inclusive of 8 miRNAs, could correctly distinguish MSI-H versus MSS colon cancer samples. Among the differentially expressed miRNAs, various members of the oncogenic miR-17-92 family were significantly up-regulated in MSS cancers. The majority of protein coding genes were also up-regulated in MSS cancers. Their functional classification revealed that they were most frequently associated with cell cycle, DNA replication, recombination, repair, gastrointestinal disease and immune response. Conclusions. This is the first report that indicates the existence of differences in miRNA expression between MSS versus MSI-H colorectal cancers. In addition, the work suggests that the combination of mRNA/miRNA expression signatures may represent a general approach for improving bio-molecular classification of human cancer.
2007-09-07 | E-TABM-326 | biostudies-arrayexpress
Project description:DNA mismatch repair deficiency (MMRD) drives microsatellite instability (MSI). Cells with MSI accumulate numerous frameshift mutations. Frameshift mutations affecting cancer-related genes may promote tumorigenesis and, therefore, are shared among independently arising MSI tumors. Consequently, such recurrent frameshift mutations can give rise to shared immunogenic frameshift peptides (FSPs) that represent ideal candidates for a vaccine against MSI cancer. Pathogenic germline variants of mismatch repair genes cause Lynch syndrome (LS), a hereditary cancer syndrome affecting approximately 20-25 million individuals worldwide. LS individuals are at high risk of developing MSI cancer. Previously, we demonstrated safety and immunogenicity of an FSP-based vaccine in a Phase I/IIa clinical trial. However, the cancer-preventive effect of FSP vaccination in the scenario of LS has not been demonstrated so far.
2021-08-30 | GSE175744 | GEO
Project description:Colorectal cancer, one of the most frequent types of malignancy in the Western world, develops through a multi-step process. The main pathways establishing transformation of normal mucosa to invasive carcinoma include chromosomal instability (CIN), microsatellite instability (MSI) or epigenetic silencing through the CpG Island Methylator Phenotype (CIMP). These pathways have distinct clinical, pathological and genetic characteristics. In general, altered cell surface glycosylation has been linked to colorectal cancer progression, however the impact of MSI-specific pathways on the glycosylation machinery of MSI colon cancer cells has not been investigated yet. In a recent study (Patsos et al., 2009) we have shown that MSI-specific mutations induce marked alterations in cell surface glycosylation, indicating specific changes in the expression of glyco-genes. Therefore the purpose of our experiment is to define these changes by glyco-gene chip analysis.
2011-09-06 | GSE31927 | GEO
Project description:The incidence and mortality of colorectal cancer (CRC) is higher in African Americans (AAs) than in other ethnic groups in the U. S., but reasons for the disparities are unknown. We performed gene expression profiling and microsatellite instability (MSI) analysis of sporadic CRCs from AAs vs. European Americans (EAs) to assess the contribution to CRC disparities. We evaluated gene expression of 43 AA and 43 EA CRC tumors matched by stage and 40 normal colon tissues using the Agilent human whole genome 4x44K cDNA arrays. Gene and pathway analysis were performed using Significance Analysis of Microarrays (SAM), 10-fold Cross Validation (10-fCV) and Ingenuity Pathway Analysis (IPA). MSI analysis was assessed with five NIH Bethesda markers. SAM revealed that 95 genes were differentially expressed between AA and EA patients at a false discovery rate of <5%. A 10f-CV demonstrated that 9 genes were differentially expressed between AA and EA with an accuracy of 97%. Nine genes (CRYBB2, PSPH, ADAL, VSIG10L, C17orf81, ARSE, ANKRD36B, ZNF835, ARHGAP6) were validated and differential expression confirmed by qRT-PCR in independent test set of 21 patients (10 AA, 11 EA). We also analyzed MSI in 57 of the CRC subjects. Overall, 15.8% of CRC patients had MSI, with a higher rate observed in EA (20%) than in AA (12%). MSI distribution by tumor site was 77% right and 23% left colon. Previously, genetic, epigenetic and environmental factors have been implicated in the etiology of CRC. Our results are the first to implicate differential gene expression in CRC disparities and support the existence of distinct tumor microenvironments in these two patients' populations. 126 total samples: 1) 43 white cancer samples; 2) 43 black cancer samples; 3) 27 white control samples; 4) 13 black control samples.
2012-05-22 | E-GEOD-28000 | biostudies-arrayexpress