O-GlcNAcylation is an essential, nutrient-sensitive post-translational modification, but its biochemical and phenotypic effects remain incompletely understood. To address this knowledge gap, we investigated the global transcriptional response to perturbations in O-GlcNAcylation. Unexpectedly, many transcriptional effects of O-GlcNAc transferase (OGT) inhibition were due to the activation of NRF2, the master regulator of redox stress tolerance. Moreover, we found that a signature of low OGT activity strongly correlates with NRF2 activation in multiple tumor expression datasets. Guided by this information, we identified KEAP1 (also known as KLHL19), the primary negative regulator of NRF2, as a direct substrate of OGT. We show that O-GlcNAcylation of KEAP1 at serine 104 is required for the efficient ubiquitination and degradation of NRF2. Interestingly, O-GlcNAc levels and NRF2 activation co-vary in response to glucose fluctuations, indicating that KEAP1 O-GlcNAcylation links nutrient sensing to downstream stress resistance. Our results reveal a novel regulatory connection between nutrient-sensitive glycosylation and NRF2 signaling, and provide a blueprint for future approaches to discover functionally important O-GlcNAcylation events on other KLHL family proteins in various experimental and disease contexts.
Glycosylation of KEAP1 links nutrient sensing to redox stress signaling.
Specimen part, Cell line
View SamplesBackground
Glioblastoma models reveal the connection between adult glial progenitors and the proneural phenotype.
Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Intra-ophthalmic artery chemotherapy triggers vascular toxicity through endothelial cell inflammation and leukostasis.
Specimen part, Treatment
View SamplesSuper-selective intra-ophthalmic artery chemotherapy (SSIOAC) is an organ-specific drug-delivery strategy to treat retinoblastoma, the most common primary ocular malignancy in children. Unfortunately, recent clinical reports associate adverse vascular toxicities with SSIOAC using melphalan, the most commonly used chemotherapeutic. To explore the reason for the unexpected vascular toxicities, we have developed in vitro studies with human retinal endothelial cells to test the effects of the chemotherapeutics and a non-human primate model to monitor the SSIOAC treatment in real-time and post-treatment. Melphalan and carboplatin (another chemotherapeutic used to treat retinoblastoma via SSIOAC) triggered migration, proliferation, and apoptosis when used to treat human retinal endothelial cells. Melphalan was associated with increased adhesion of leukocytes to human retinal endothelial cells, and tended to increase with increased cell expression of adhesion proteins (ICAM-1) and soluble chemotactic factors (IL-8). Histopathology post-SSIOAC indicated vessel wall sloughing, leukostasis, and vessel occlusion. We have established an in vitro human cell culture model and a non-human primate model to evaluate strategies designed to obviate vascular side effects, and optimize the efficacy of SSIAOC and the drug preparations used in SSIOAC.
Intra-ophthalmic artery chemotherapy triggers vascular toxicity through endothelial cell inflammation and leukostasis.
Specimen part, Treatment
View SamplesSuper-selective intra-ophthalmic artery chemotherapy (SSIOAC) is an organ-specific drug-delivery strategy to treat retinoblastoma, the most common primary ocular malignancy in children. Unfortunately, recent clinical reports associate adverse vascular toxicities with SSIOAC using melphalan, the most commonly used chemotherapeutic. To explore the reason for the unexpected vascular toxicities, we have developed in vitro studies with human retinal endothelial cells to test the effects of the chemotherapeutics and a non-human primate model to monitor the SSIOAC treatment in real-time and post-treatment. Melphalan and carboplatin (another chemotherapeutic used to treat retinoblastoma via SSIOAC) triggered migration, proliferation, and apoptosis when used to treat human retinal endothelial cells. Melphalan was associated with increased adhesion of leukocytes to human retinal endothelial cells, and tended to increase with increased cell expression of adhesion proteins (ICAM-1) and soluble chemotactic factors (IL-8). Histopathology post-SSIOAC indicated vessel wall sloughing, leukostasis, and vessel occlusion. We have established an in vitro human cell culture model and a non-human primate model to evaluate strategies designed to obviate vascular side effects, and optimize the efficacy of SSIAOC and the drug preparations used in SSIOAC.
Intra-ophthalmic artery chemotherapy triggers vascular toxicity through endothelial cell inflammation and leukostasis.
Specimen part, Treatment
View SamplesPlasmodium berghei ANKA infection in mice is used as a model for human cerebral malaria, the most severe complication of Plasmodium falciparum infection. The response of brain cells such as microglia has been little investigated, and may play a role in the pathogenesis or regulation of cerebral malaria. We showed previously that microglia are activated in P. berghei infections, and that Type 1 Interferon signaling is important for activation. This dataset contains the transcriptome of brain microglia of infected mice in the presence and absence of Type I interferon signaling, with the aim of identifying the genes involved in this pathway in microglia during experimental cerebral malaria. Refererence: Capuccini et al 2016, Scientific Reports, 6:39258
Transcriptomic profiling of microglia reveals signatures of cell activation and immune response, during experimental cerebral malaria.
Sex, Specimen part, Treatment
View SamplesThe tissue-specific pattern of mRNA expression can indicate important clues about gene function. High-density oligonucleotide arrays offer the opportunity to examine patterns of gene expression on a genome scale. Toward this end, we have designed custom arrays that interrogate the expression of the vast majority of protein-encoding human and mouse genes and have used them to profile a panel of 79 human and 61 mouse tissues. The resulting data set provides the expression patterns for thousands of predicted genes, as well as known and poorly characterized genes, from mice and humans. We have explored this data set for global trends in gene expression, evaluated commonly used lines of evidence in gene prediction methodologies, and investigated patterns indicative of chromosomal organization of transcription. We describe hundreds of regions of correlated transcription and show that some are subject to both tissue and parental allele-specific expression, suggesting a link between spatial expression and imprinting.
A gene atlas of the mouse and human protein-encoding transcriptomes.
No sample metadata fields
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Waterpipe smoking induces epigenetic changes in the small airway epithelium.
Specimen part
View SamplesWaterpipe (also called hookah, shisha, or narghile) smoking is a common form of tobacco use in the Middle East. Its use is becoming more prevalent in Western societies, especially among young adults as an alternative form of tobacco use to traditional cigarettes. While the risk to cigarette smoking is well documented, the risk to waterpipe smoking is not well defined with limited information on its health impact at the epidemiologic, clinical and biologic levels with respect to lung disease. Based on the knowledge that airway epithelial cell DNA methylation is modified in response to cigarette smoke and in cigarette smoking-related lung diseases, we assessed the impact of light-use water-pipe smoking on DNA methylation of the small airway epithelium (SAE) and whether changes in methylation were linked to the transcriptional output of the cells. Small airway epithelium was obtained from 7 nonsmokers and 7 light-use (2.6 1.7 sessions/wk) waterpipe-only smokers. Genome-wide comparison of SAE DNA methylation of waterpipe smokers to nonsmokers identified 727 probesets differentially methylated (fold-change >1.5, p<0.05) representing 673 unique genes. Dominant pathways associated with these epigenetic changes include those linked to G-protein coupled receptor signaling, aryl hydrocarbon receptor signaling and xenobiotic metabolism signaling, all of which have been associated with cigarette smoking and lung disease. Of the genes differentially methylated, 11.3% exhibited a corresponding significant (p<0.05) change in gene expression with enrichment in pathways related to regulation of mRNA translation and protein synthesis (eIF2 signaling and regulation of eIF4 and p70S6K signaling). Overall, these data demonstrate that light-use waterpipe smoking is associated with epigenetic changes and related transcriptional modifications in the SAE, the cell population demonstrating the earliest pathologic abnormalities associated with chronic cigarette smoking.
Waterpipe smoking induces epigenetic changes in the small airway epithelium.
Specimen part
View SamplesMouse glioblastomas were induced by lentiviral vector expressing HrasG12V and shRNA against p53. Tumor tissues were isolated from mice reached clinical endpoints. RNA was isolated using the RNeasy kit according to manufacturer’s protocol with the addition of DNase (Qiagen). cDNA libraries were prepared using the TruSeq RNA Sample Prep kit (Illumina). RNA sequencing was performed using a HiSeq 2500 Sequencing System (Illumina). Overall design: 3 normal mouse brain samples compared to 5 glioblastoma samples by standard RNAseq method.
Targeting NF-κB in glioblastoma: A therapeutic approach.
Specimen part, Subject
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