TERT is an essential protein component of telomerase, a ribonuclearprotein complex that protects chromosomal ends. Ectopic expression of TERT in mouse skin activates hair follicle stem cells and induces active growth phase of hair cycles, called anagen. This activity of TERT is independent of its reverse transcriptase function, indicating that this is a non-telomeric function of TERT.
TERT promotes epithelial proliferation through transcriptional control of a Myc- and Wnt-related developmental program.
No sample metadata fields
View SamplesMany cancers are postulated to harbor developmental hierarchies in which cells display variability in stem-like character, tumor propagating ability, and proliferation. In glioblastoma (GBM), glioma stem cells (GSCs) reside atop such a tumor cellular hierarchy, and are thought to resist current therapies and thus underlie inevitable relapse. Here we show that GSCs can evade RTK inhibition by reversibly regressing to a slow-cycling state reminiscent of quiescent neural stem cells. This process involves up-regulation of numerous histone demethylases, including KDM6A/B, which remodel the chromatin landscape and are selectively essential for drug persister survival. Chromatin remodeling is accompanied by activation of various neurodevelopmental master regulators and Notch signaling, changes which closely parallel critical aspects of neural stem cell biology. Thus our findings illustrate how cancer cells may hijack native developmental programs for deranged proliferation, adaptation, and tolerance in the face of stress. Our studies highlight key roles for chromatin remodeling and developmental plasticity in GBM biology, and suggest strategies for overcoming therapeutic resistance by targeting epigenetic and developmental pathways. Overall design: ChIP-seq for histone modifications and Notch factors in glioblastoma stem cell lines with various drug treatments RNA-seq in glioblastoma stem cell lines with various drug treatments
Adaptive Chromatin Remodeling Drives Glioblastoma Stem Cell Plasticity and Drug Tolerance.
No sample metadata fields
View SamplesDominantly inherited expanded repeat neurodegenerative diseases are typically caused by the expansion of existing variable copy number tandem repeat sequences in otherwise unrelated genes. Repeats located in translated regions encode polyglutamine that is thought to be the toxic agent, however in several instances the expanded repeat is in an untranslated region, necessitating multiple pathogenic pathways or an alternative common toxic agent. As numerous clinical features are shared by several of these diseases, and expanded repeat RNA is a common intermediary, RNA has been proposed as a common pathogenic agent. Various forms of repeat RNA are toxic in animal models, by multiple distinct pathways. In Drosophila, repeat-containing double-stranded RNA (rCAG.rCUG~100) toxicity is dependent on Dicer processing evident with the presence of single-stranded rCAG7, which have been detected in affected HD brains. Microarray analysis of Drosophila rCAG.rCUG~100 repeat RNA toxicity revealed perturbation of several pathways including innate immunity. Recent reports of elevated circulating cytokines prior to clinical onset, and age-dependent increased inflammatory signaling and microglia activation in the brain, suggest that immune activation precedes neuronal toxicity. Since the Toll pathway is activated by certain forms of RNA, we assessed the role of this pathway in RNA toxicity. We find that rCAG.rCUG~100 activates Toll signaling and that RNA toxicity is dependent on this pathway. The sensitivity of RNA toxicity to autophagy further implicates innate immune activation. Expression of rCAG.rCUG~100 was therefore directed in glial cells and found to be sufficient to cause neuronal dysfunction. Non-autonomous toxicity due to expanded repeat-containing double-stranded RNA mediated activation of innate immunity is therefore proposed as a candidate pathway for this group of human genetic diseases.
Distinct roles for Toll and autophagy pathways in double-stranded RNA toxicity in a Drosophila model of expanded repeat neurodegenerative diseases.
Sex, Specimen part, Disease
View SamplesRecent evidence supports a role for RNA as a common pathogenic agent in both the polyglutamine and untranslated dominant expanded repeat disorders. One feature of all repeat sequences currently associated with disease is their predicted ability to form a hairpin secondary structure at the RNA level. In order to investigate mechanisms by which hairpin forming repeat RNAs could induce neurodegeneration, we have looked for alterations in gene transcripts as hallmarks of the cellular response to toxic hairpin repeat RNAs. Three disease associated repeat sequences - CAG, CUG and AUUCU - were specifically expressed in the neurons of Drosophila and resultant common, early, transcriptional changes assessed by microarray analyses. Transcripts that encode several components of the Akt/Gsk3- signalling pathway were altered as a consequence of expression of these repeat RNAs, indicating that this pathway is a component of the neuronal response to these pathogenic RNAs and may represent an important common therapeutic target in this class of diseases.
Perturbation of the Akt/Gsk3-β signalling pathway is common to Drosophila expressing expanded untranslated CAG, CUG and AUUCU repeat RNAs.
Sex, Age, Specimen part
View SamplesThe WWOX gene spans chromosomal fragile site FRA16D, a region of DNA instability in cancer. While WWOX has some tumor suppressor characteristics, its normal role and functional contribution to cancer are unclear. Drosophila homozygous Wwox mutants are viable with no discernable phenotype. Drosophila Wwox interactors, identified by proteomics and micro-array analyses, mainly have roles in aerobic metabolism. Functional relationships between Wwox and either isocitrate dehydrogenase (IDH) or superoxide dismutase 1 (Sod1) were confirmed by phenotype modification, including Sod1 crinkled-wing, indicative of oxidative stress response. Endogenous reactive oxygen species levels reflect Wwox levels in Drosophila. WWOX mRNA levels in Drosophila and human cells correlate with IDH and Sod1 levels. Wwox therefore contributes to pathways involving glucose metabolism and oxidative stress response.
Drosophila orthologue of WWOX, the chromosomal fragile site FRA16D tumour suppressor gene, functions in aerobic metabolism and regulates reactive oxygen species.
Specimen part
View SamplesIntroduction: Sepsis is a complex immunological response to infection characterized by early hyperinflammation followed by severe and protracted immunosuppression, suggesting that a multi-marker approach has the greatest clinical utility for early detection, within a clinical environment focused on SIRS differentiation. Pre-clinical research using an equine sepsis model identified a panel of gene expression biomarkers that define the early aberrant immune activation. Thus, the primary objective was to apply these gene expression biomarkers to distinguish patients with sepsis from those who had undergone major open surgery and had clinical outcomes consistent with systemic inflammation due to physical trauma and wound healing.
Development and validation of a novel molecular biomarker diagnostic test for the early detection of sepsis.
Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Normal stroma suppresses cancer cell proliferation via mechanosensitive regulation of JMJD1a-mediated transcription.
Specimen part, Disease stage, Cell line, Subject
View SamplesMatrix induced effects on gene expression in HeLa and MDA-MB-231 cells
Normal stroma suppresses cancer cell proliferation via mechanosensitive regulation of JMJD1a-mediated transcription.
Cell line
View Samplesgene expression data from 3 pairs of cancer associated fibroblasts and normal fibroblasts from the same individual Overall design: mRNA seq data from 3 normal and 3 cancer associated fibroblast cell lines
Normal stroma suppresses cancer cell proliferation via mechanosensitive regulation of JMJD1a-mediated transcription.
Specimen part, Disease stage, Subject
View SamplesThe v-erbA oncogene belongs to a superfamily of transcription factors called nuclear receptors, which includes the retinoic acid receptors (RARs) responsible for mediating the effects of retinoic acid (RA). Nuclear receptors bind to specific DNA sequences in the promoter region of target genes and v-erbA is known to exert a dominant negative effect on the activity of the RARs. The repressor activity of v-erbA has been linked to the development of hepatocellular carcinoma (HCC) in a mouse model. We have used microarray analysis to identify genes differentially expressed in hepatocytes in culture (AML12 cells) stably transfected with v-erbA and exposed to RA. We have found that v-erbA can affect expression of RA-responsive genes. We have also identified a number of v-erbA-responsive genes that are known to be involved in carcinogenesis and which may play a role in the development of HCC.
Modulation of expression of RA-regulated genes by the oncoprotein v-erbA.
Specimen part, Cell line
View Samples