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GSE54192
Mus musculus
9 Downloadable Samples
Affymetrix Mouse Gene 2.0 ST Array (mogene20st)
Description
NCoR1 (Nuclear receptor Co-Repressor) and SMRT (Silencing Mediator of Retinoid and Thyroid hormone receptor) are well-recognized coregulators of nuclear receptor (NR) action. However, their unique roles in the regulation of thyroid hormone (TH) signaling in specific cell types have not been determined. To accomplish this we generated a mouse model that lacked function of either NCoR1 or SMRT or both in the liver only. Despite both corepressors being present in the liver, SMRT had no ability to regulate TH signaling when deleted in either euthyroid or hypothyroid animals. In contrast, disruption of NCoR1 action confirmed that it is the principal mediator of TH sensitivity in vivo. While SMRT played little role in TH signaling alone, when disrupted in combination with NCoR1 it greatly accentuated the activation of hepatic lipogenesis regulated by NCoR1. Thus, corepressor specificity exists in vivo and NCoR1 is the principal regulator of TH action in the liver. However, both NCoR1 and SMRT collaborate to control hepatic lipogenesis and lipid storage, which likely reflects their cooperative activity in regulating the action of multiple NRs including the thyroid hormone receptor (TR).
Publication Title
NCoR1 and SMRT play unique roles in thyroid hormone action in vivo.
Sample Metadata Fields
Sex, Specimen part
View Samples- Mus musculus
- 12 Downloadable Samples
- Affymetrix Mouse Gene 1.0 ST Array (mogene10st)
Description
The thyroid hormone receptor (TR) has been proposed to regulate target genes in the absence of triiodothyronine (T3), through the recruitment of the corepressors, NCoR and SMRT. NCoR and SMRT may thus play a key role in both hypothyroidism and resistance to thyroid hormone, though this has never been tested in vivo. To accomplish this we developed mice that express in the liver a NCoR protein (L-NCoRID) that cannot interact with the TR. L-NCoRID mice develop normally, however when made hypothyroid the repression of many positively regulated T3-target genes is abrogated, demonstrating that NCoR plays a specific and sufficient role in repression by the unliganded TR. Remarkably, in the euthyroid state, expression of many T3-targets are also upregulated in L-NCoRID mice, demonstrating that NCoR also determines the magnitude of the response to T3 in euthyroid animals. While positive T3 targets were upregulated in L-NCoRID mice in the hypo and euthyroid state there was less effect seen on negatively regulated T3 target genes. Thus, NCoR is a specific regulator of T3-action in vivo and mediates the activity of the unliganded TR. Furthermore, NCoR may play a key role in determining the differences in individual responses to similar levels of circulating T3.
Publication Title
The nuclear corepressor, NCoR, regulates thyroid hormone action in vivo.
Sample Metadata Fields
No sample metadata fields
View Samples- Danio rerio
- 6 Downloadable Samples
NextSeq 500
Description
The SWI/SNF-family chromatin remodeling protein ATRX is a tumor suppressor in sarcomas, gliomas and other malignancies. Its loss of function facilitates the alternative lengthening of telomeres (ALT) pathway in tumor cells, while it also affects Polycomb repressive complex 2 (PRC2) silencing of its target genes. To further define the role of inactivating ATRX mutations in carcinogenesis, we knocked out atrx in our previously published p53/nf1-deficient zebrafish line that develops malignant peripheral nerve sheath tumors and gliomas. Complete inactivation of atrx using CRISPR-cas9 was lethal in developing fish and resulted in an alpha-thalassemia-like phenotype including reduced alpha-globin expression. In p53/nf1-deficient zebrafish neither peripheral nerve sheath tumors nor gliomas showed accelerated onset in atrx+/- fish, but these fish developed various tumors that were not observed in their atrx+/+ siblings, including epithelioid sarcoma, angiosarcoma, undifferentiated pleomorphic sarcoma and rare types of carcinoma. Most of these cancer types are included in the AACR Genie database of human tumors associated with mutant ATRX, indicating that our zebrafish model reliably reflects a role for ATRX-loss in the early pathogenesis of these types of human cancers. RNA-seq of p53/nf1- and p53/nf1/atrx-deficient tumors revealed that down-regulation of telomerase accompanied ALT-mediated lengthening of the telomeres in atrx-mutant samples. Moreover, inactivating mutations in atrx disturbed PRC2-target gene silencing, indicating a connection between ATRX loss and PRC2 dysfunction in cancer development. Overall design: Gene expression values were derived from paired end RNA-Seq data that compared zebrafish samples from p53/nf1/atrx-deficient tumors to samples from atrx-wildtype controls (3 vs. 3 samples).
Publication Title
Loss of atrx cooperates with p53-deficiency to promote the development of sarcomas and other malignancies.
Sample Metadata Fields
Subject
View Samples- Homo sapiens
- 65 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
Background & Aims: Chronic hepatitis C virus (HCV) infection is complicated by hepatic fibrosis. Hypothesizing that fibrogenic signals may originate in cells susceptible to HCV infection, gene expression of hepatocytes was analyzed from persons with chronic HCV at different stages of liver fibrosis. Methods: HCV-infected subjects with significant liver fibrosis (Ishak fibrosis 3) were matched for age, race, and gender to subjects with minimal fibrosis (Ishak fibrosis 0-1). RNA from portal tracts and hepatic parenchyma was isolated from biopsies by laser capture and transcriptome profiling was performed using hybridization arrays. Results: Portal tracts from both groups were enriched for immune related genes when compared to hepatocytes but high fibrosis subjects showed a loss of this enrichment. Hepatocytes from persons with high fibrosis were depleted for genes involved in small molecule and drug metabolism, especially butyrylcholinesterase (BCHE), a gene involved in the metabolism of drugs of abuse. Differential expression of BCHE was validated in the same tissues using qPCR. Cross-sectional and longitudinal testing in an expanded cohort of HCV-infected individuals showed that serum BCHE activity decreased in advance of progression to fibrosis. Conclusion: Chronic HCV infection is associated with a loss of hepatocyte metabolic function, decreased enrichment of immune-related genes in portal tracts and downregulation of BCHE in hepatocytes. Our results indicate that BCHE may be involved in the progression of fibrosis during HCV infection among injection drug users and may serve as a useful marker for fibrosis progression.
Publication Title
Laser captured hepatocytes show association of butyrylcholinesterase gene loss and fibrosis progression in hepatitis C-infected drug users.
Sample Metadata Fields
Sex, Age, Race
View Samples- Mus musculus
- 12 Downloadable Samples
- Affymetrix Mouse Gene 1.0 ST Array (mogene10st)
Description
We found that the circadian protein PER2 interacts with the nuclear receptor PPARgamma to repress its activity. PPARgamma is a master regulator of adipogenesis and lipid metabolism and is very abundant in adipose tissue. We used microarrays to detail the global program of gene expression in adipose tissue lacking the per2 gene. This analysis identified several PPARgamma target genes up-regulated in adipose tissue from per2-/- mice.
Publication Title
PER2 controls lipid metabolism by direct regulation of PPARγ.
Sample Metadata Fields
Sex, Age, Specimen part
View Samples- Homo sapiens
- 6 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
NOTCH proteins regulate signaling pathways involved in cellular differentiation, proliferation and death. Overactive Notch signaling as been observed in numerous cancers and has been extensively studied in the context of T-cell acute lymphoblastic leukemia (T-ALL) where more than 50% of pateints harbour mutant NOTCH1. Small molecule modulators of these proteins would be important for understanding the role of NOTCH proteins in malignant and normal biological processes.
Publication Title
Direct inhibition of the NOTCH transcription factor complex.
Sample Metadata Fields
Specimen part, Cell line
View Samples- Homo sapiens
- 11 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
Expression of a constitutively active Notch-1 intracellular domain (NICD) in MCF-10A cells was found to induce two distinct types of 3D structures: large, hyperproliferative structures and small, growth-arrested structures with reduced cell-to-matrix adhesion. These heterogeneous phenotypes reflect differences in Notch pathway activation levels. High Notch activity caused loss of cell adhesion and inhibition of proliferation, whereas low Notch activity maintained matrix adhesion and provoked a strong hyperproliferative response. In order to gain insight into the dosage-dependent transcriptional events triggered by Notch1 activation, gene expression profiles induced 48 hours after infection of MCF-10A cells with retroviral vectors expressing full-length Notch-1, L1601P+P, or NICD were compared. Full-length Notch-1 induced the weakest effect, L1601P+P induced an intermediate effect and NICD induced the strongest effect. Results provide insight into the dichotomous activites of Notch during development and tumorigenesis.
Publication Title
Dose-dependent induction of distinct phenotypic responses to Notch pathway activation in mammary epithelial cells.
Sample Metadata Fields
Cell line
View Samples- Mus musculus
- 9 Downloadable Samples
- Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
Platelets are a rich source of many cytokines and chemokines including transforming growth factor -1 (TGF1). TGF1 is required to convert conventional CD4+ T (Tconv) cells into induced regulatory T (iTreg) cells that express the transcription factor Foxp3. To explore whether other platelet contents will affect the properties of TGF induced Treg cell, we used platelet lysate that contain many other cytokines and chemokines besides TGF1 (pltTGF) to induce Foxp3 expression (pltTGFb-iTreg) from conventional CD4+ T (Tconv) cells. We used purified TGF1 to induce Treg (purTGF-iTreg) cells as a control. Gene expression profiles in iTreg cells were analyzed by microarray asay.
Publication Title
TGF-β1 along with other platelet contents augments Treg cells to suppress anti-FVIII immune responses in hemophilia A mice.
Sample Metadata Fields
No sample metadata fields
View Samples- Homo sapiens
- 8 Downloadable Samples
- Illumina Genome Analyzer IIx
Description
Despite initial and often dramatic responses of epidermal growth factor receptor (EGFR)-addicted lung tumors to the EGFR-specific tyrosine kinase inhibitors (TKIs), gefitinib and erlotinib, nearly all develop resistance and relapse. To explore novel mechanisms mediating acquired resistance, we employed non-small-cell lung cancer (NSCLC) cell lines bearing activating mutations in EGFR and rendered them resistant to EGFR-specific TKIs through chronic adaptation in tissue culture. In addition to previously observed resistance mechanisms including EGFR-T790M ''gate-keeper'' mutations and MET amplification, a subset of the seven chronically adapted NSCLC cell lines including HCC4006, HCC2279 and H1650 cells exhibited marked induction of fibroblast growth factor (FGF) 2 and FGF receptor 1 (FGFR1) mRNA and protein. Also, adaptation to EGFR-specific TKIs was accompanied by an epithelial to mesenchymal transition (EMT) as assessed by changes in CDH1, VIM, ZEB1 and ZEB2 expression and altered growth properties in Matrigel. In adapted cell lines exhibiting increased FGF2 and FGFR1 expression, measures of growth and signaling, but not EMT, were blocked by FGFR-specific TKIs, an FGF-ligand trap and FGFR1 silencing with RNAi. In parental HCC4006 cells, cell growth was strongly inhibited by gefitinib, although drug-resistant clones progress within 10 days. Combined treatment with gefitinib and AZD4547, an FGFR-specific TKI, prevented the outgrowth of drug-resistant clones. Thus, induction of FGF2 and FGFR1 following chronic adaptation to EGFR-specific TKIs provides a novel autocrine receptor tyrosine kinase-driven bypass pathway in a subset of lung cancer cell lines that are initially sensitive to EGFR-specific TKIs. The findings support FGFR-specific TKIs as potentially valuable additions to existing targeted therapeutic strategies with EGFR-specific TKIs to prevent or delay acquired resistance in EGFR-driven NSCLC. Overall design: Examination of mRNA levels in DMSO and gefitinib-resistant cultures of HCC4006 and HCC827. Each group has two replicates.
Publication Title
A mechanism of resistance to gefitinib mediated by cellular reprogramming and the acquisition of an FGF2-FGFR1 autocrine growth loop.
Sample Metadata Fields
Specimen part, Cell line, Treatment, Subject
View Samples- Mus musculus
- 6 Downloadable Samples
- Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
Although transcriptional programs associated with T-cell specification and commitment have been described, the functional hierarchy and the roles of key regulators in structuring/ orchestrating these programs remain unclear. Activation of Notch signaling in uncommitted precursors by the thymic stroma initiates the T-cell differentiation program. One regulator first induced in these precursors is the DNA binding protein Tcf-1, a T-cell specific mediator of Wnt signaling. Yet the specific contribution of Tcf-1 to early T-cell development and the signals inducing it in these cells remain unclear. Here we assign functional significance to Tcf-1 as a gatekeeper of T-cell fate. We show that Tcf-1 is directly activated by Notch signals. Tcf-1 is required at the earliest phase of Tcell determination for progression beyond the early thymic progenitor (ETP) stage. The global expression profile of Tcf-1 deficient progenitors indicates that basic processes of DNA metabolism are downregulated in its absence and the blocked T-cell progenitors become abortive and die by apoptosis. Our data thus add an important functional relationship to the roadmap of T-cell development.
Publication Title
T-cell factor 1 is a gatekeeper for T-cell specification in response to Notch signaling.
Sample Metadata Fields
Specimen part
View Samples