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Mus musculus
6 Downloadable Samples
Illumina HiSeq 2500
Description
The tumor suppressor TP53 is mutated in the majority of human cancers, including over 70% of pancreatic ductal adenocarcinoma (PDAC). Wild-type p53 accumulates in response to cellular stress and regulates the expression of genes that alter cell fate and constrain tumorigenesis. p53 also modulates several cellular metabolic pathways, though it remains unclear whether particular p53-regulated metabolites contribute to tumor suppression or whether metabolic alterations driven by p53 mutation sustain cancer progression. Here, we show that restoring endogenous p53 function in cancer cells derived from a murine PDAC model driven by oncogenic Kras and a regulatable p53 short hairpin RNA (shRNA) rewires glucose and glutamine metabolism leading to the accumulation of a-ketoglutarate (aKG), an obligate substrate for several chromatin modifying enzymes. p53 induces transcriptional programs characteristic of premalignant differentiation, an effect that can be partially recapitulated by addition of cell permeable aKG. Similarly, enforcing aKG accumulation in p53-deficient PDAC cells though the inhibition of oxoglutarate (aKG) dehydrogenase (Ogdh), the enzyme that consumes aKG in the tricarboxylic acid cycle, reduces tumor-initiating capacity and promotes tumor cell differentiation. Decreases in 5-hydroxymethylcytosine (5hmC), an aKG-dependent chromatin modification, are associated with the appearance of p53 mutations in the transition from premalignant to de-differentiated malignant lesions, whereas increases in 5hmC accompany tumor cell differentiation triggered by either p53 restoration or Ogdh depletion. Together these data nominate aKG as an effector of p53-mediated tumor suppression whose accumulation in p53-deficient tumors can drive tumor cell differentiation and antagonize malignant progression. Overall design: 6 samples were analyzed in duplicates of 3 conditions. 1. Control, KPsh cells grown on dox, treated with vehicle DMSO for 72 hours. 2. KPsh cells grown on dox, treated with 4mM cell permeable dimethyl-alpha ketoglutarate for 72 hours. 3. KPsh cells grown off dox for 8 days, treated with DMSO vehicle for 72 hours.
Publication Title
α-Ketoglutarate links p53 to cell fate during tumour suppression.
Sample Metadata Fields
Cell line, Treatment, Subject
View Samples- Homo sapiens
- 35 Downloadable Samples
Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
Cancer cells interact with surrounding stromal fibroblasts during tumorigenesis, but the complex molecular rules that govern these interactions remain poorly understood, thus hindering the development of therapeutic strategies to target cancer stroma. We have taken a mathematical approach to begin defining these rules by performing large-scale quantitative analysis of fibroblast effects on cancer cell proliferation across more than four hundred heterotypic cell line pairings. Systems-level modeling of this complex dataset using singular value decomposition revealed that normal tissue fibroblasts variably express at least two functionally distinct activities, one which reflects transcriptional programs associated with activated mesenchyme, that act either coordinately or at cross-purposes to modulate cancer cell proliferation. To gain insight into the molecular identity of these fibroblast activities, we isolated RNA from 36 human skin and lung fibroblast cell line monocultures from Coriell Repositories or ATCC and performed microarray-based gene expression profiling using Affymetrix gene chips.
Publication Title
Systems-level modeling of cancer-fibroblast interaction.
Sample Metadata Fields
Sex, Age, Race
View Samples- Homo sapiens
- 27 Downloadable Samples
- Illumina HiSeq 2000
Description
Metastasis-initiating cells dynamically adapt to the distinct microenvironments of different organs, but these early adaptations are poorly understood due to the limited sensitivity of in situ transcriptomics. We developed fluorouracil-labeled RNA sequencing (Flura-seq) for in situ analysis with unprecedented sensitivity. Flura-seq utilizes cytosine deaminase (CD) to convert fluorocytosine to fluorouracil, covalently labeling nascent RNA for purification and sequencing. Flura-seq revealed that breast cancer micrometastases in lung and brain exhibit unique, reversible gene signatures depending on the microenvironment. Specifically, the mitochondrial electron transport Complex I and the NRF2-driven antioxidant programs were induced in oxygen-rich pulmonary micrometastases, compared to mammary tumors or brain micrometastases. Loss of Complex I activity, and antioxidant supplementation potentiated pulmonary metastatic growth. We confirm lung metastasis-specific NRF2 overexpression in clinical samples, thus validating Flura-seq's utility in identifying clinically actionable microenvironmental adaptations in early metastasis. The sensitivity, robustness and economy of Flura-seq are broadly applicable beyond cancer research. Overall design: Examination of 5-FU labeled RNAs in cancer cells present in different organs
Publication Title
Flura-seq identifies organ-specific metabolic adaptations during early metastatic colonization.
Sample Metadata Fields
Cell line, Subject
View Samples
GSE56321- Mus musculus
- 12 Downloadable Samples
- Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
Sirtuins are a family of protein deacetylases, deacylases, and ADP-ribosyltransferases that regulate life span, control the onset of numerous age-associated diseases, and mediate metabolic homeostasis. We have uncovered a novel role for the mitochondrial sirtuin SIRT4 in the regulation of hepatic lipid metabolism during changes in nutrient availability. We show that SIRT4 levels decrease in the liver during fasting and that SIRT4 null mice display increased expression of hepatic peroxisome proliferator activated receptor (PPAR ) target genes associated with fatty acid catabolism. Accordingly, primary hepatocytes from SIRT4 knockout (KO) mice exhibit higher rates of fatty acid oxidation than wild-type hepatocytes, and SIRT4 overexpression decreases fatty acid oxidation rates. The enhanced fatty acid oxidation observed in SIRT4 KO hepatocytes requires functional SIRT1, demonstrating a clear cross talk between mitochondrial and nuclear sirtuins. Thus, SIRT4 is a new component of mitochondrial signaling in the liver and functions as an important regulator of lipid metabolism.
Publication Title
SIRT4 represses peroxisome proliferator-activated receptor α activity to suppress hepatic fat oxidation.
Sample Metadata Fields
Sex, Specimen part
View Samples- Mus musculus
- 26 Downloadable Samples
- Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
Calorie restriction (CR) is a dietary intervention that extends lifespan and healthspan in a variety of organisms. CR improves mitochondrial energy production, fuel oxidation and reactive oxygen species scavenging in skeletal muscle and other tissues, and these processes are thought to be critical to the benefits of CR. PGC-1a is a transcriptional coactivator that regulates mitochondrial function and is induced by CR. Consequently, many of the mitochondrial and metabolic benefits of CR are attributed to increased PGC-1a activity. To test this model for the first time, we examined the metabolic and mitochondrial response to CR in mice lacking skeletal muscle PGC-1a (MKO). Surprisingly, MKO mice demonstrated a normal improvement in glucose homeostasis in response to CR, indicating that skeletal muscle PGC-1a is dispensable for the whole-body benefits of CR. In contrast, gene expression profiling and electron microscopy demonstrated that PGC-1a is required for the full CR-induced increases in mitochondrial gene expression and mitochondrial density in skeletal muscle. These results demonstrate that PGC-1a is a major regulator of the mitochondrial response to CR in skeletal muscle, but surprisingly show that neither PGC-1a nor mitochondrial biogenesis in skeletal muscle are required for the metabolic benefits of CR.
Publication Title
Skeletal muscle transcriptional coactivator PGC-1α mediates mitochondrial, but not metabolic, changes during calorie restriction.
Sample Metadata Fields
Specimen part
View Samples- Mus musculus
- 10 Downloadable Samples
- Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
Tumor cells exhibit aberrant metabolism characterized by high glycolysis even in the presence of oxygen. This metabolic reprogramming, known as the Warburg effect, provides tumor cells with the substrates and redox potential required for the generation of biomass. Here, we show that the mitochondrial NAD-dependent deacetylase SIRT3 is a crucial regulator of the Warburg effect. SIRT3 loss promotes a metabolic profile consistent with high glycolysis required for anabolic processes in vivo and in vitro. Mechanistically, SIRT3 mediates metabolic reprogramming independently of mitochondrial oxidative metabolism and through HIF1a, a transcription factor that controls expression of key glycolytic enzymes. SIRT3 loss increases reactive oxygen species production, resulting in enhanced HIF1a stabilization. Strikingly, SIRT3 is deleted in 40% of human breast cancers, and its loss correlates with the upregulation of HIF1a target genes. Finally, we find that SIRT3 overexpression directly represses the Warburg effect in breast cancer cells. In sum, we identify SIRT3 as a regulator of HIF1a and a suppressor of the Warburg effect.
Publication Title
SIRT3 opposes reprogramming of cancer cell metabolism through HIF1α destabilization.
Sample Metadata Fields
Specimen part
View Samples- Mus musculus
- 18 Downloadable Samples
- Illumina HiSeq 2500
Description
Ubiquilins are a family of proteins involved in proteasomal degradation of mislocalized membrane proteins. Here, Greer et al. demonstrate that Ubqln1 is required for BCR-driven B cell proliferation through maintenance of protein synthesis following stimulation. In the absence of Ubqln1, mitochondrial proteins accumulate in the cytosol, which may account for the observed proteostasis. BCR stimulation of murine B cells induced a long-lasting mitochondrial depolarization that did not occur in response to LPS. We hypothesize that in the absence of Ubqln1, mitochondrial depolarization leads to an accumulation of mitochondrial membrane proteins in the cytosol, which leads to translational inhibition and a cell cycle block. Overall design: For RNASeq, cells were stimulated in triplicate in 2*10e6 cells/mL for 4 hours with either 10 µg/mL anti-IgM F(ab)2 or 20 µg/mL LPS, or no stimulation. There were 18 total samples, 9 Knockout samples, 9 WT samples, 3 biological replicates per treatment group: no stimulation, 10 ug/mL a-Igm, 20 ug/mL LPS.
Publication Title
Ubiquilin1 promotes antigen-receptor mediated proliferation by eliminating mislocalized mitochondrial proteins.
Sample Metadata Fields
Specimen part, Cell line, Treatment, Subject
View Samples- Arabidopsis thaliana
- 12 Downloadable Samples
- Affymetrix Arabidopsis ATH1 Genome Array (ath1121501)
Description
Aims: To determine the changes in the Arabidopsis axillary bud transcriptome in response to changes in the red light (R) to far red light (FR) ratio (R:FR).
Publication Title
Abscisic acid regulates axillary bud outgrowth responses to the ratio of red to far-red light.
Sample Metadata Fields
Specimen part, Treatment
View Samples- Rattus norvegicus
- 30 Downloadable Samples
- Affymetrix Rat Genome 230 2.0 Array (rat2302)
Description
To determine the effects of age and lipoic acid supplementation on hepatic gene expression, we fed young (3 months) and old (24 months) male Fischer 344 rats a diet with or without 0.2% (w/w) R--lipoic acid (LA) for two weeks. Total RNA isolated from liver tissue was analyzed by Affymetrix microarray to examine changes in transcriptional profile. Results showed an increase in pro-inflammatory gene expression in the aging liver, with increased immune cell function and tissue remodeling genes, representing 45% of the age-related transcriptome changes. Increased inflammation was corroborated by increases in soluble ICAM1 levels with age. There were also observed age-related increases in transcription of genes related to lipid and cholesterol synthesis including Acetyl CoA Carboxylase (Acacb) and Fatty acid Synthase (Fasn). Supplementation of old animals with LA did not reverse this necro-inflammatory phenotype, yet limited age-associated hepatic dyslipidemia. Dietary LA further affected a small but concerted number of hepatic genes regardless of age. These included declines in lipid and bile synthesis genes. Decline in lipid synthesis genes was further corroborated by a decrease in Fasn and Acc protein levels. Intriguingly, LA also altered the expression of genes governing circadian rhythm, most notably Bmal1, Npas2, and Per2, which changed in a coordinated manner with respect to their rhythmic transcription. Thus, advanced age is associated with a necro-inflammatory phenotype and increased lipid synthesis, while chronic LA supplementation influences hepatic genes associated with energy metabolism and circadian rhythm regardless of age.
Publication Title
R-α-lipoic acid does not reverse hepatic inflammation of aging, but lowers lipid anabolism, while accentuating circadian rhythm transcript profiles.
Sample Metadata Fields
Sex, Age, Specimen part
View Samples- Mus musculus
- 12 Downloadable Samples
- Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
In cytotoxic T cells (CTL), Protein Kinase B /Akt is activated by the T cell antigen receptor (TCR) and the cytokine Interleukin 2 (IL2), in part by phosophorylation of Akt by Phospholipid dependent kinase 1 (PDK1).
Publication Title
Protein kinase B controls transcriptional programs that direct cytotoxic T cell fate but is dispensable for T cell metabolism.
Sample Metadata Fields
Specimen part
View Samples