The maintenance of advanced malignancies relies on continued activity of driver oncogenes, although their rate-limiting role is highly context-dependent with respect to tumor types and associated genetic alterations. Oncogenic Kras mutation is the signature event in human pancreatic ductal adenocarcinoma (PDAC), serving a critical role in tumor initiation. Here, an inducible KrasG12D-driven p53 mutant PDAC mouse model establishes that advanced PDAC remains strictly dependent on continued KrasG12D expression and that KrasG12D serves a vital role in the control of tumor metabolism, through stimulation of glucose uptake and channeling of glucose intermediates through the hexosamine biosynthesis pathway (HBP) and the pentose phosphate pathway (PPP). Notably, these studies reveal that oncogenic Kras regulates ribose biogenesis. Unlike canonical models of PPP-mediated ribose biogenesis, we demonstrate that oncogenic Kras drives intermediates from enhanced glycolytic flux into the non-oxidative arm of the PPP, thereby decoupling ribose biogenesis from NADPNADPH-mediated redox control. Together, this work provides in vivo mechanistic insights into how oncogenic Kras promotes metabolic reprogramming in native tumors and illuminates potential metabolic targets that can be exploited for therapeutic benefit in Kras-driven PDAC.
Oncogenic Kras maintains pancreatic tumors through regulation of anabolic glucose metabolism.
Specimen part, Treatment
View SamplesMurine GVH-SSc dorsal scapular skin samples were analyzed to determine the effect of IFNAR-1 inhibition on gene expression at day 14 and day 28. Gene expression in GVH-SSc skin from mice treated with a neutralizing IFNAR-1 antibody was compared to that in GVH-SSc skin from mice treated with isotype IgG, with skin from syngeneic graft controls as reference.
Type I IFNs Regulate Inflammation, Vasculopathy, and Fibrosis in Chronic Cutaneous Graft-versus-Host Disease.
Sex
View SamplesThe restoration of catalytic activity to mutant enzymes by small molecules is well-established for in vitro systems. Here we show that the protein tyrosine kinase Src R388A mutant can be rescued in live cells using the small molecule imidazole. Cellular rescue of a v-Src homolog was rapid and reversible and conferred predicted oncogenic properties. Using chemical rescue in combination with mass spectrometry, six known Src kinase substrates were confirmed, and several new protein targets identified. Chemical rescue data suggests that c-Src is active under basal conditions. Rescue of R388A c-Src also allowed contributions of Src to the MAP kinase pathway to be clarified. This chemical rescue approach is likely to be of broad utility in cell signaling.
Chemical rescue of a mutant enzyme in living cells.
No sample metadata fields
View SamplesDetailed information about stage-specific changes in gene expression is crucial for understanding the gene regulatory networks underlying development and the various signal transduction pathways contributing to morphogenesis. Here, we describe the global gene expression dynamics during early murine limb development, when cartilage, tendons, muscle, joints, vasculature, and nerves are specified and the musculoskeletal system of the limbs is established. We used whole-genome microarrays to identify genes with differential expression at 5 stages of limb development (E9.5 to 13.5), during fore-limb and hind-limb patterning. We found that the onset of limb formation is characterized by an up-regulation of transcription factors, which is followed by a massive activation of genes during E10.5 and E11.5 which tampers off at later time points. Among 3520 genes identified as significantly up-regulated in the limb, we find ~30% to be novel, dramatically expanding the repertoire of candidate genes likely to function in the limb. Hierarchical and stage-specific clustering identified expression profiles that correlate with functional programs during limb development and are likely to provide new insights into specific tissue patterning processes. Here we provide for the first time, a comprehensve analysis of developmentally regulated genes during murine limb development, and provide some novel insights into the expression dynamics governing limb morphogenesis.
Global gene expression analysis of murine limb development.
Specimen part
View SamplesBACKGROUND: p53 is an important tumor suppressor with a known role in the later stages of colorectal cancer, but its relevance to the early stages of neoplastic initiation remains somewhat unclear. Although p53-dependent regulation of Wnt signalling activity is known to occur, the importance of these regulatory mechanisms during the early stages of intestinal neoplasia has not been demonstrated.
A limited role for p53 in modulating the immediate phenotype of Apc loss in the intestine.
Specimen part
View SamplesNotch signaling is widely implicated in mouse mammary gland development and tumorigenesis. To investigate the effects of acute activation of Notch signaling in the mammary epithelial compartment, we generated bi-transgenic MMTV-rtTA; TetO-NICD1 (MTB/TICNX) mice that conditionally express a constitutively active NOTCH1 intracellular domain (NICD1) construct in the mammary epithelium upon doxycycline administration.
Notch promotes recurrence of dormant tumor cells following HER2/neu-targeted therapy.
Sex, Age, Specimen part, Treatment, Time
View SamplesBackground: It has been shown previously that administration of Francisella tularensis (Ft) LVS lipopolysaccharide (LPS) protects mice against subsequent challenge with Ft LVS and blunts the pro-inflammatory cytokine response.
Modulation of hepatic PPAR expression during Ft LVS LPS-induced protection from Francisella tularensis LVS infection.
Age, Specimen part
View SamplesGene expression profiling was carried out on splenocyte mRNA samples collected from 10 animals subject to repeated social threat (pooled into 2 groups of 5) and 10 animals subject to non-threatening control conditions (pooled into 2 groups of 5). The primary research question is whether gene expression differs in CD11b+ splenocytes from animals exposed to social threat vs non-threatening control conditions.
Computational identification of gene-social environment interaction at the human IL6 locus.
Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
MicroRNA-mRNA interactions in a murine model of hyperoxia-induced bronchopulmonary dysplasia.
Specimen part, Disease, Disease stage, Treatment
View SamplesRegulatory T cells (Tregs) can suppress a wide variety of cell types, in diverse organ sites and inflammatory conditions. While Tregs possess multiple suppressive mechanisms, the number required for maximal function is unclear. Furthermore, whether any inter-relationship orcross-regulatory mechanisms exist that areused to orchestrate and control their utilization is unknown. Here we assessed the functional capacity of Tregs lacking the ability to secrete both interleukin-10 (IL-10) and IL-35, which individually are required for maximal Treg activity. Surprisingly, IL-10/IL-35-double deficient Tregswere fully functionalin vitro and in vivo. Loss of IL-10 and IL-35 was compensated for by a concurrent increase in cathepsin E (CTSE) expression, enhanced TRAIL (Tnfsf10)expression and soluble TRAIL release, rendering IL-10/IL-35-double deficient Tregsfunctionally dependent on TRAIL in vitro and in vivo. Lastly, while C57BL/6 Tregs are IL-10/IL-35-dependent, Balb/c Tregs, which express high levels of CTSE and enhanced TRAIL expression, are TRAIL-dependent.These data reveal that cross-regulatory pathways exist, which control the utilization of suppressive mechanisms,thereby providing Tregfunctional plasticity.
The plasticity of regulatory T cell function.
Specimen part
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