Barretts esophagus confers significant risk of esophageal adenocarcinoma. We have established the cloning of patient-matched stem cells of Barretts, gastric, and esophageal epithelium. Barrett's esophagus stem cells (BE), gastric cardia stem cells (GC) and normal esophagus stem cells (Eso) from 12 patients were cloned (For BE: 12 patients, GC: 12 patients and Eso: 2 patients). Keratin 5 positive and Keratin 7 positive cells were cloned from human fetal esophageal epithelium. Using air liquid interface culture system, stem cells were induced to differentiate into mature epithelial structures.
Mutational spectrum of Barrett's stem cells suggests paths to initiation of a precancerous lesion.
Specimen part, Disease, Subject
View SamplesBarretts esophagus confers significant risk of esophageal adenocarcinoma. We have established the cloning of patient-matched stem cells of Barretts, gastric, and esophageal epithelium. Transplantation of transformed Barretts stem cells yielded tumors with hallmarks of esophageal adenocarcinoma, whereas transformed esophageal stem cells produced squamous cell carcinomas. These findings define a stem cell target in a precancerous lesion for preemptive therapies.
Mutational spectrum of Barrett's stem cells suggests paths to initiation of a precancerous lesion.
Specimen part, Disease
View SamplesBarretts esophagus is a precancerous lesion that confers a significant risk of esophageal adenocarcinoma. Strategies for selective eradication of Barretts have been stymied by our inability to identify the Barretts stem cell. Here we employ novel technologies to clone patient-matched stem cells of Barretts, gastric, and esophageal epithelium. Genomic analyses of Barretts stem cells reveal a patient-specific mutational spectrum ranging from low somatic variation similar to patient-matched gastric epithelial stem cells to ones marked by extensive heterozygous alteration of genes implicated in tumor suppression, epithelial planarity, and epigenetic regulation. Transplantation of transformed Barretts stem cells yields tumors with hallmarks of esophageal adenocarcinoma, whereas transformed esophageal stem cells yield squamous cell carcinomas. Thus Barretts develops from cells distinct from local eponymous epithelia, emerges without obvious driver mutations, and likely progresses through and from the generation of dominant clones. These findings define a stem cell target for preemptive therapies of a precancerous lesion.
Mutational spectrum of Barrett's stem cells suggests paths to initiation of a precancerous lesion.
Specimen part, Disease, Disease stage
View SamplesTranscriptome of murine testis from wild type mice and mice lacking telomerase for three generations (G3-Terc), Ku86 or both telomerase and Ku86.
Effectors of mammalian telomere dysfunction: a comparative transcriptome analysis using mouse models.
No sample metadata fields
View SamplesWe profiled total mRNA of pancreas and kidney tissues of 3 different strains (p53-null; In4a/Arf-null and WT) of reprogrammable mouse lines (they all express OCT4, SOX2, KLF4, C-MYC under the control of a tetracycline promoter, activated by doxycycline) Overall design: 5 mice of each genotype were treated with doxycycline to induce the expression of the reprogramming factors, they were sacrificed and total mRNA was extracted from pancreas and kidney tissues (we mapped >24M reads per sample)
Tissue damage and senescence provide critical signals for cellular reprogramming in vivo.
Specimen part, Cell line, Subject
View SamplesWhe embryonic stem cells are in vitro expanded threir telomereres lengthen, in the absence of genetic manipulations, concomitant with the loss of heterochromatic marks. In order to analyze whether there would be changes in gene expression during in vitro expansion we performed RNA-seq and found no substantial differences in gene expression at passage 6 or 16. Overall design: Embryonic stem (ES) cells were derived from blastocysts expressing GFP in the Rosa26 locus. Four independent lines of ES were in vitro expanded to passage 16. Total RNA was extracted from each independent clones, RNA was extracted and prepared for RNA-seq.
Generation of mice with longer and better preserved telomeres in the absence of genetic manipulations.
Specimen part, Cell line, Treatment, Subject
View SamplesRecent studies suggest that telomerase promotes cell growth by mechanisms that extend beyond the rescue of critically short telomeres. The in vitro model of mTert overexpressing MEFs recapitulates fundamental aspects of the growth-promoting effects of mTert in vivo. First, in Terc-proficient cells, mTert overexpression favors escape from replicative senescence and enhances anchorage-independent growth in response to oncogenic stress, which fits well with previous data showing that mTert overexpression promotes tumor formation. Second, in Terc-deficient cells, retroviral transduction with mTert results in a delayed onset of immortalization and impairs colony formation in response to oncogenic stress, which is in agreement with the inhibitory effect of mTert overexpression on tumorigenesis in a Terc null mouse background. To unravel the molecular targets of telomerase that impact on cell growth, we compared the transcriptome of MEFs, before and after mTert introduction. We found that ectopic expression of mTert was associated with detectable gene expression changes (greater than 1.5-fold; validated by qRT-PCR) of 26 transcripts. Analysis of the observed transcriptional changes indicates that ectopic expression of mTert suppresses in a coordinated manner functionally related genes with overlapping roles in growth arrest, resistance to transformation, and apoptosis. We show that the majority of the telomerase target genes are growth-inhibitory, transforming growth factor-beta (TGF-beta) -inducible genes and provide functional evidence for the potential of telomerase to abrogate TGF-beta -mediated growth inhibition. Thus, in line with the current view that the diversity of TGF-beta responses is not so much a consequence of the use of different signaling pathways but caused by different ways of reading the output from the same basic pathway, we propose that the telomerase status of a cell creates a gene expression pattern that determines how cells read growth inhibitory signals, among them signals propagated through the TGF-beta pathway.
Expression of mTert in primary murine cells links the growth-promoting effects of telomerase to transforming growth factor-beta signaling.
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View SamplesThe basic defect of IgA nephropathy (IgAN) lies within peripheral blood mononuclear cells rather than local kidney abnormalities. Previously we showed an altered gene expression in monocytes compared to B and T cells isolated from IgAN patients (Kidney Int, 2010), thus our aim here was to study this subset more closely at genome-wide level.
Altered monocyte expression and expansion of non-classical monocyte subset in IgA nephropathy patients.
Specimen part, Disease
View SamplesGene expression from bone-marrow drived macrophages of WT and SREBP-1a deficient mice
Linking lipid metabolism to the innate immune response in macrophages through sterol regulatory element binding protein-1a.
No sample metadata fields
View SamplesAlthough glucocorticoids (GCs) are known to exert numerous effects in the hippocampus, their chronic regulatory functions remain poorly understood. Moreover, evidence is inconsistent regarding the longstanding hypothesis that chronic GC exposure promotes brain aging/Alzheimer's disease. Here, we adrenalectomized male F344 rats at 15-months-of-age, maintained them for 3 months with implanted corticosterone (CORT) pellets producing low or intermediate (glucocorticoid-receptor (GR)-activating) blood levels of CORT, and performed microarray/pathway analyses in hippocampal CA1. We defined the chronic GC-dependent transcriptome as 393 genes that exhibited differential expression between Intermediate- and Low-CORT groups. Short-term CORT (4 days) did not recapitulate this transcriptome. Functional processes/pathways overrepresented by chronic CORT-upregulated genes included learning/plasticity, differentiation, glucose metabolism and cholesterol biosynthesis, whereas processes overrepresented by CORT-downregulated genes included inflammatory/immune/glial responses and extracellular structure. These profiles indicate that GCs chronically activate neuronal/metabolic processes while coordinately repressing a glial axis of reactivity/inflammation. We then compared the GC-transcriptome with a previously-defined hippocampal aging transcriptome, revealing a high proportion of common genes. Although CORT and aging moved expression of some common genes in the same-direction, the majority were shifted in opposite directions by CORT and aging (e.g., glial inflammatory genes downregulated by CORT are upregulated with aging). These results contradict the hypothesis that GCs simply promote brain aging, and also suggest that the opposite-direction shifts during aging reflect resistance to CORT regulation. Therefore, we propose a new model in which aging-related GC resistance develops in some target pathways while GC overstimulation develops in others, together generating much of the brain aging phenotype.
Glucocorticoid-dependent hippocampal transcriptome in male rats: pathway-specific alterations with aging.
Sex, Age, Specimen part
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