Colorectal cancer is one of the most common cancers in the world. Histological staging is efficient but combination with molecular markers may improve tumors classification. Gene expression profiles have been defined as prognosis predictors among stage II and III tumors but their implementation in medical practice remains controversial. Stage-II tumors have been recognized as a heterogeneous group and high-risk morphologic features have been retained as justifying adjuvant chemotherapy. We propose here the investigation of clinical features and expression profiles from stage II and stage III colon carcinomas without DNA mismatch repair defect. A series of 130 colon cancer samples was retained. Expression profiles were established on oligonucleotide microarrays and processed in the R/Bioconductor environment. Hierarchical then supervised analyses were successively performed applying the data-sampling approach. A molecular signature of seven genes was found to cluster stage III tumors with an adjusted p-values lower than 10^-10. A subgroup of stage-II tumors aggregated this cluster in both series. No correlation was found between with the disease severity but the function of the discriminating genes suggests that tumors have been classified according to their putative response to adjuvant targeted or classic therapies. Further pharmacogenetic studies might document this observation.
A seven-gene signature aggregates a subgroup of stage II colon cancers with stage III.
Sex, Age, Specimen part
View SamplesAnalysis of expression profiles in stage II colon cancer according to the APC gene status
Expression Profiles in Stage II Colon Cancer According to APC Gene Status.
Sex, Age, Specimen part
View SamplesWe report an applicaton of small RNA sequencing using high throughput next generation sequencing to identify the small RNA content of cell lines. By sequencing over 30 million reads we could identify a new class of small RNAs previousy observed with tiling arrays and mapping to promoter regions of coding genes. We also identified a large number of small RNAs corresponding to internal exons of coding genes. By using different enzymatic treatments and immunoprecipitation experiments, we have determined that both the promoter associated small RNAs as well as ones within the body of the genes bear 5'' cap structures. Overall design: Examination of the expression of small RNAs (<200nt).
Post-transcriptional processing generates a diversity of 5'-modified long and short RNAs.
No sample metadata fields
View SamplesPhenotypic changes induced by extracellular vesicles (EVs) have been implicated in the recovery of acute kidney injury (AKI) induced by mesenchymal stromal cells (MSCs). miRNAs are potential candidates for cell reprogramming towards a pro-regenerative phenotype. The aim of the present study was to evaluate whether miRNA de-regulation inhibits the regenerative potential of MSCs and derived-EVs in a model of glycerol-induced AKI in SCID mice. For this purpose, we generated MSCs depleted of Drosha, a critical enzyme of miRNA maturation, to alter miRNA expression within MSCs and EVs. Drosha knock-down MSCs (MSC-Dsh) maintained the phenotype and differentiation capacity. They produced EVs that did not differ from those of wild type cells in quantity, surface molecule expression and internalization within renal tubular epithelial cells. However, EVs derived from MSC-Dsh (EV-Dsh) showed global down-regulation of miRNAs. Whereas, wild type MSCs and derived EVs were able to induce morphological and functional recovery in AKI, MSC-Dsh and EV-Dsh were ineffective. RNA sequencing analysis showed that genes deregulated in the kidney of AKI mice were restored by treatment with MSCs and EVs but not by MSC-Dsh and EV-Dsh. Gene Ontology analysis showed that down-regulated genes in AKI were associated with fatty acid metabolism. The up-regulated genes in AKI were involved in inflammation, ECM-receptor interaction and cell adhesion molecules. These alterations were reverted by treatment with wild type MSCs and EVs, but not by the Drosha counterparts. In conclusion, miRNA depletion in MSCs and EVs significantly reduced their intrinsic regenerative potential in AKI, suggesting a critical role of miRNAs. Overall design: RNA-seq
AKI Recovery Induced by Mesenchymal Stromal Cell-Derived Extracellular Vesicles Carrying MicroRNAs.
No sample metadata fields
View SamplesDengue virus (DENV) infection is one of the most serious public health problems worldwide. A recent dengue outbreak in Paraguay (2007-2009) presented unusual manifestations such as hepatitis, encephalitis, pulmonary as well as cardiac disorders associated with 50% of deaths caused by dengue in the country. Despite the knowledge on inflammatory responses observed during the course of disease, the role of innate immune cells in the control of virus replication influencing clinical outcome is poorly defined. Using two clinical isolates of the virus, a non-fatal case of classical DF (DENV3/290) and a fatal case of DF with visceral complications (DENV3/5532), we sought to determine the profile of dengue infection in human dendritic cell, a major innate immune cell population. Compared to classical DENV3/290, the strain DENV3/5532 displayed higher replicative ability in mdDCs. In addition, DENV3/5532 was found to induce elevated production of pro-inflammatory cytokines associated with higher rates of programmed cell death. The observed phenotype was due to viral replication in mdDCs and TNF appeared to display a protective effect on virus-induced mdDCs apoptosis. These results suggest that the fatal case DENV3/5532 isolate modulates dendritic cell survival as well as inflammatory mediators synthesis.
Dengue virus type 3 isolated from a fatal case with visceral complications induces enhanced proinflammatory responses and apoptosis of human dendritic cells.
Specimen part, Time
View SamplesChromatin-based functional genomic analyses and genomewide association studies (GWASs) together implicate enhancers as critical elements influencing gene expression and risk for common diseases. Here, we performed systematic chromatin and transcriptome profiling in human pancreatic islets. Integrated analysis of islet data with those generated by the ENCODE project in nine cell types identified specific and significant enrichment of type 2 diabetes and related quantitative trait GWAS variants in islet enhancers. Our integrated chromatin maps reveal that most enhancers are short (median = 0.8 kb). Each cell type also contains a substantial number of more extended (=3 kb) enhancers. Interestingly, these stretch enhancers are often tissue-specific and overlap locus control regions, suggesting that they are important chromatin regulatory beacons. Indeed, we show that (i) tissue specificity of enhancers and nearby gene expression increase with enhancer length; (ii) neighborhoods containing stretch enhancers are enriched for important cell type-specific genes; and (iii) GWAS variants associated with traits relevant to a particular cell type are more enriched in stretch enhancers compared with short enhancers. Reporter constructs containing stretch enhancer sequences exhibited tissue-specific activity in cell culture experiments and in transgenic mice. These results suggest that stretch enhancers are critical chromatin elements for coordinating cell type-specific regulatory programs and that sequence variation in stretch enhancers affects risk of major common human diseases. Overall design: Integrated analysis of islet chromatin modification and transcriptome data with those generated by the ENCODE project. NISC Comparative Sequencing Program
Chromatin stretch enhancer states drive cell-specific gene regulation and harbor human disease risk variants.
No sample metadata fields
View SamplesBackground: Glioblastoma multiforme (GBM) is the most aggressive and most lethal primary malignant brain tumor, correlated with survival rates of less than one year from the time of diagnosis. Current surgical procedure attempts to remove the bulk of the tumor mass, whereas GBM frequently recurs within 1-3cm from the primary tumor resection site. Molecular mechanisms involved in the recurrence of the tumor are still poorly understood. The aim of the study was to define the molecular signature of GBM surrounding white matter (WM) in order to better understand the molecular mechanisms involved with tumor relapse.
Gene expression profile of glioblastoma peritumoral tissue: an ex vivo study.
No sample metadata fields
View SamplesThe cellular response to replication stress requires the DNA-damage responsive kinase ATM and its co-factor ATMIN, however the roles of this signaling pathway following replication stress are unclear. RNA-seq and subsequent differential expression analyses were utilized to identify the functions of ATM and ATMIN in response to replication stress induced by Aphidcolin (APH). Overall design: Mouse Embryonic Fibroblasts (MEFs) deleted for ATM or ATMIN were treated with 1µM APH or DMSO as a control. Two different wild-type MEF cell lines (wtATM, wtATMIN) served as controls. RNA-seq was performed in duplicates, in a total of 32 samples, with an average of 31.1M aligned readsobtained per group,with 15.5M reads obtained per replicate.
A Comprehensive Analysis of the Dynamic Response to Aphidicolin-Mediated Replication Stress Uncovers Targets for ATM and ATMIN.
Specimen part, Treatment, Subject
View SamplesWe performed microarray analysis to derive gene signatures down-stream of soluble CD40 ligand stimulation in human naive B cells. Nave B cells were purified from healthy donor PBMC using negative selection beads (Miltenyi) and cultured with sCD40L at 2.5ug/ml for 6hr before microarray analysis. In the same study, cells were also harvested at day 5 post-stimulation to confirm sCD40L-induced B cell activation and proliferation. FACS analysis confirmed soluble CD40L induced up-regulation of CD86 and CD69 at 24hr. B cell proliferation was measured at day 4 post-stimulation by EdU incorporation.
CD40L-Dependent Pathway Is Active at Various Stages of Rheumatoid Arthritis Disease Progression.
Specimen part, Treatment, Subject
View SamplesWe performed microarray analysis of sCD40L-stimulated iDC to derive a signature of CD40 activation. Human monocytes from normal healthy donors were differentiated to iDCs with GM-CSF and IL4. FACS analysis demonstrated the immature status of these cells, illustrated by low expression of CD80, CD40, and CD86. We confirmed that sCD40L induces the maturation of DCs, characterized by higher expression of CD80, HLA-DR, CD86, CD83 and CD40 and secretion of pro-inflammatory cytokines at 24hr post-stimulation. Cells were harvested at 1, 3 and 24hr post-stimulation for microarray analysis.
CD40L-Dependent Pathway Is Active at Various Stages of Rheumatoid Arthritis Disease Progression.
Specimen part, Treatment, Subject
View Samples