prenatal stress response, genetic modification
Differential effects of prenatal stress in 5-Htt deficient mice: towards molecular mechanisms of gene × environment interactions.
Sex, Specimen part, Treatment
View SamplesIntestinal polyposis, a precancerous neoplasia, results primarily from an abnormal increase in the number of crypts. Crypts contain intestinal stem cells (ISCs). Thus intestinal polyposis provides an ideal condition for studying stem cell involvement in polyp/tumor formation. Using a conditional knock-out mouse model, we found that the tumor suppressor Phosphatase of Tension homolog (PTEN) governs the proliferation rate and number of ISCs and loss of PTEN results in an excess of ISCs. In PTEN mutants, excess ISCs initiate de-novo crypt formation and crypt fission, recapitulating crypt production in fetal/neonatal intestine. Microarray studies were used to profile the changes in gene expression that occurred when PTEN was knocked out in the intestine.
PTEN-deficient intestinal stem cells initiate intestinal polyposis.
No sample metadata fields
View SamplesBarrier integrity is central to the maintenance of a healthy immunological homeostasis. Impaired skin barrier function is linked with enhanced allergen sensitization and the development of diseases such as atopic dermatitis (AD), which can precede the development of other allergic diseases such as food allergies and asthma. Epidemiological evidence indicates that children suffering from allergies have lower levels of dietary fibre-derived short-chain fatty acids (SCFA). Using an experimental model of AD, we report that a fermentable fibre-rich diet alleviates AD severity and systemic allergen sensitization. The gut-skin axis underpins this phenomenon through SCFA, which strengthen skin barrier integrity by altering mitochondrial metabolism of epidermal keratinocytes. SCFA promote keratinocyte differentiation and the production of key structural lipids, resulting in enhanced barrier function. Our results demonstrate that dietary fibre and SCFA mitigate AD by improving barrier integrity, ultimately limiting early systemic allergen sensitization and development of disease. Overall design: 16 Samples, 4 groups in duplicate
Gut-derived short-chain fatty acids modulate skin barrier integrity by promoting keratinocyte metabolism and differentiation.
Genotype, Disease, Disease stage, Treatment, Subject
View SamplesGlioblastoma (GBM) is a highly lethal brain tumor presenting as one of two subtypes with distinct clinical histories and molecular profiles. The primary GBM subtype presents acutely as high-grade disease that typically harbors EGFR, PTEN and Ink4a/Arf mutations, and the secondary GBM subtype evolves from the slow progression of low-grade disease that classically possesses PDGF and p53 events1. Here, we show that concomitant CNS-specific deletion of p53 and Pten in the mouse CNS generates a penetrant acute-onset high-grade malignant glioma phenotype with striking clinical, pathological and molecular resemblance to primary GBM in humans. This genetic observation prompted p53 and PTEN mutational analysis in human primary GBM, demonstrating unexpectedly frequent inactivating mutations of p53 as well the expected PTEN mutations. Integrated transcriptomic profling, in silico promoter analysis and functional studies of murine neural stem cells (NSCs) established that dual, but not singular, inactivation of p53 and Pten promotes an undifferentiated state with high renewal potential and drives elevated c-Myc levels and its associated signature. Functional studies validated increased c-Myc activity as a potent contributor to the impaired differentiation and enhanced renewal of p53-Pten null NSCs as well as tumor neurospheres (TNSs) derived from this model. c-Myc also serves to maintain robust tumorigenic potential of p53-Pten null TNSs. These murine modeling studies, together with confirmatory transcriptomic/promoter studies in human primary GBM, validate a pathogenetic role of a common tumor suppressor mutation profile in human primary GBM and establish c-Myc as a key target for cooperative actions of p53 and Pten in the regulation of normal and malignant stem/progenitor cell differentiation, self-renewal and tumorigenic potential.
p53 and Pten control neural and glioma stem/progenitor cell renewal and differentiation.
No sample metadata fields
View SamplesThis SuperSeries is composed of the SubSeries listed below.
EMT inducers catalyze malignant transformation of mammary epithelial cells and drive tumorigenesis towards claudin-low tumors in transgenic mice.
Specimen part, Cell line
View SamplesThe newly identified claudin-low subtype of cancer is believed to represent the most primitive breast malignancies, having arisen from transformation of an early epithelial precursor with inherent stemness properties and metaplastic features. Challenging this hypothesis, we show both in vitro and in vivo that transcription factors inducing epithelial-mesenchymal transition can drive the development of claudin-low tumors from differentiated mammary epithelial cells, by playing a dual role in cell transformation and dedifferentiation.
EMT inducers catalyze malignant transformation of mammary epithelial cells and drive tumorigenesis towards claudin-low tumors in transgenic mice.
Specimen part, Cell line
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