To evaluate the prognostic relevance of molecular subtypes and key transcription factors in pancreatic ductal adenocarcinoma (PDAC), we performed gene expression analysis of whole-tumor tissue obtained from 118 surgically resected PDAC and 13 control samples.
Prognostic relevance of molecular subtypes and master regulators in pancreatic ductal adenocarcinoma.
Specimen part
View SamplesPurpose: To explore the side population (SP) in pancreatic ductal adenocarcinoma (PDAC) for its gene expression profile and its association to cancer stem cells (CSC) and to evaluate the value of genes from its gene signature on patient survival.
Human pancreatic cancer contains a side population expressing cancer stem cell-associated and prognostic genes.
Sex, Age, Specimen part, Disease stage
View SamplesTo unravel the molecular mechanisms mediating the effects of androgens on spermatogenesis, testicular gene expression was compared in mice with a Sertoli cell-selective androgen receptor knockout (SCARKO) and littermate controls on postnatal d 10. At this age testicular cell composition is still comparable in SCARKOs and controls. Microarray analysis identified 692 genes with significant differences in expression. A more than 2-fold up- or downregulation by androgen action in Sertoli cells was observed for 28 and 6 genes respectively. The biological relevance of the strongly upregulated genes was supported by the finding that several of them were previously described to be androgen-regulated or essential for spermatogenesis. Serine protease inhibitors were overrepresented in the same subgroup suggesting a role for androgens in cell junction dynamics and tissue restructuring events during spermatogenesis. A time course experiment (d8-d20), followed by cluster analysis allowed the identification of typical expression patterns of differentially expressed testicular genes during initiation of spermatogenesis. Three genes with a pattern closely resembling that of Pem, a prototypal androgen-regulated gene in Sertoli cells, were selected for confirmation by RT-PCR and further analysis. The data confirm that the SCARKO model allows identification of novel androgen-regulated genes in the testis. This particular series represents all data from d 10. The additional expression data from the time course (d8-d20) is represented by series GSE2259 ("Testicular gene expression in SCARKO mice during prepuberty").
The effect of a sertoli cell-selective knockout of the androgen receptor on testicular gene expression in prepubertal mice.
No sample metadata fields
View SamplesTo unravel the molecular mechanisms mediating the effects of androgens on spermatogenesis, testicular gene expression was compared in mice with a Sertoli cell-selective androgen receptor knockout (SCARKO) and littermate controls on postnatal d 10. At this age testicular cell composition is still comparable in SCARKOs and controls. Microarray analysis identified 692 genes with significant differences in expression. A more than 2-fold up- or downregulation by androgen action in Sertoli cells was observed for 28 and 6 genes respectively. The biological relevance of the strongly upregulated genes was supported by the finding that several of them were previously described to be androgen-regulated or essential for spermatogenesis. Serine protease inhibitors were overrepresented in the same subgroup suggesting a role for androgens in cell junction dynamics and tissue restructuring events during spermatogenesis. A time course experiment (d8-d20), followed by cluster analysis allowed the identification of typical expression patterns of differentially expressed testicular genes during initiation of spermatogenesis. Three genes with a pattern closely resembling that of Pem, a prototypal androgen-regulated gene in Sertoli cells, were selected for confirmation by RT-PCR and further analysis. The data confirm that the SCARKO model allows identification of novel androgen-regulated genes in the testis.
The effect of a sertoli cell-selective knockout of the androgen receptor on testicular gene expression in prepubertal mice.
No sample metadata fields
View SamplesSustained Ca2+ entry into CD4+CD8+ double-positive thymocytes is required for positive selection. We identified a voltage-gated Na+ channel (VGSC), essential for positive selection of CD4+ T cells. Pharmacological inhibition of VGSC activity inhibited sustained Ca2+ influx induced by positive-selecting ligands and in vitro positive selection of CD4+ but not CD8+ T cells. In vivo shRNA knockdown of Scn5a specifically inhibited positive selection of CD4+ T cells. Ectopic expression of VGSC in peripheral AND CD4+ T cells bestowed the ability to respond to a positively selecting ligand, directly demonstrating VGSC expression was responsible for increased sensitivity. Thus active VGSCs in thymocytes provides a mechanism by which a weak positive selecting signal can induce sustained Ca2+ signals required for CD4+ T cell development.
A voltage-gated sodium channel is essential for the positive selection of CD4(+) T cells.
Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
ELF5 suppresses estrogen sensitivity and underpins the acquisition of antiestrogen resistance in luminal breast cancer.
Cell line, Treatment, Time
View SamplesMutations affecting the RAS-MAPK pathway frequently occur in relapse neuroblastoma tumors, which suggests that activation of this pathway is associated with a more aggressive phenotype. To explore this hypothesis we generated several model systems to define a neuroblastoma RAS-MAPK pathway signature. We could show that activation of this pathway in primary tumors indeed correlates with poor survival and is associated with known activating mutations in ALK and other RAS-MAPK pathway genes. From integrative analysis we could show that mutations in PHOX2B, CIC and DMD are also associated with an activated RAS-MAPK pathway. Mutation of PHOX2B and deletion of CIC in neuroblastoma cell lines induces activation of the RAS-MAPK pathway. This activation was independent of phosphorylated ERK in the CIC knock out systems. Furthermore, deletion of CIC causes a significant increase in tumor growth in vivo. These results show that the RAS-MAPK pathway is involved in tumor progression, and establish CIC as a powerful tumor suppressor that functions downstream of this pathway in neuroblastoma.
RAS-MAPK Pathway-Driven Tumor Progression Is Associated with Loss of CIC and Other Genomic Aberrations in Neuroblastoma.
Cell line
View SamplesInflorescence stages 1 to 12 from mutants involved in Arabidopsis small RNA metabolism. Three biological replicates of each mutant comprising at least 9 independent plants were harvested, and the expression profiles were determined using Affymetrix ATH1 arrays. Comparisons among the sample groups allow the identification of genes regulated by small RNAs (microRNAs and siRNAs).
microRNA-directed phasing during trans-acting siRNA biogenesis in plants.
No sample metadata fields
View SamplesT helper cell subsets have unique calcium (Ca2+) signals when activated with identical stimuli. The regulation of these Ca2+ signals and their correlation to the biological function of each T cell subset remains unclear. Trpm4 is a Ca2+-activated cation channel that we found is expressed at higher levels in Th2 cells compared to Th1 cells. Inhibition of Trpm4 expression increased Ca2+ influx and oscillatory levels in Th2 cells and decreased influx and oscillations in Th1 cells. This inhibition of Trpm4 expression also significantly altered T cell cytokine production and motility. Our experiments revealed that decreasing Trpm4 levels divergently regulates nuclear localization of NFAT. Consistent with this, gene profiling did not show Trpm4 dependent transcriptional regulation and T-bet and GATA-3 levels remain identical. Thus, Trpm4 is expressed at different levels on T helper cells and plays a distinctive role in T cell function by differentially regulating Ca2+ signaling and NFAT localization.
Trpm4 differentially regulates Th1 and Th2 function by altering calcium signaling and NFAT localization.
Specimen part, Treatment, Time
View SamplesThe primary aim of this study was to evaluate the changes in hepatocyte gene expression under short-term hypoxic conditions in wild type and HIF-1a null cultures. To this end, hypoxia treated cultures were subjected to incubation with 1% O2/5% CO2/94% N2 at 37 C for eight hours prior to RNA isolation. Duplicate normoxic controls were established from separate animals wherein cultures were untreated and treated with Adbgal. Biological triplicates of wild type and HIF-1a null cultures were placed under hypoxic conditions and subsequently processed for microarray analysis. A total of 10 microarray hybridizations were performed.
In vitro liver tissue model established from transgenic mice: role of HIF-1alpha on hypoxic gene expression.
No sample metadata fields
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