ROR?t is well recognized as the lineage defining transcription factor for TH17 cell development. However, the cell-intrinsic mechanisms that negatively regulate TH17 cell development and autoimmunity remain poorly understood. Here we demonstrate that the transcriptional repressor REV-ERBa is exclusively expressed in TH17 cells, competes with ROR?t for their shared DNA consensus sequence, and negatively regulates TH17 cell development via repression of genes traditionally characterized as ROR?t-dependent, including Il17a. Deletion of REV-ERBa enhanced TH17-mediated pro-inflammatory cytokine expression, exacerbating experimental autoimmune encephalomyelitis (EAE) and colitis. Treatment with REV-ERB-specific synthetic ligands, which have similar phenotypic properties as ROR? modulators, suppressed TH17 cell development, was effective in colitis intervention studies, and significantly decreased the onset, severity, and relapse rate in several models of EAE without affecting thymic cellularity. Our results establish that REV-ERBa negatively regulates pro-inflammatory TH17 responses in vivo and identifies the REV-ERBs as potential targets for the treatment of TH17-mediated autoimmune diseases. Overall design: 10 samples; 5 conditions with 2 replicates per condition
REV-ERBα Regulates T<sub>H</sub>17 Cell Development and Autoimmunity.
Specimen part, Subject
View SamplesHuman microvascular endothelial cells (HMVEC) treated with vascular endothelial growth factor (VEGF), Antrhax Edema Toxin (ET), or the Epac activator, 8-pCPT-2'-O-Me-cAMP (8CPT)
Anthrax edema toxin inhibits endothelial cell chemotaxis via Epac and Rap1.
Specimen part, Treatment
View SamplesMicroRNAs are endogenously expressed small non-coding RNAs that regulate gene expression on the posttranscriptional level. The miR-17-92 cluster (encoding miR-17, -18a, -19a/b, -20a and miR-92a) is highly expressed in tumor cells and is up-regulated by ischemia. Whereas miR-92a was recently identified as negative regulator of angiogenesis, the specific functions of the other members of the cluster are less clear. Here we demonstrate that overexpression of miR-17, -18a, -19a and -20a significantly inhibited 3D spheroid sprouting in vitro, whereas inhibition of miR-17, -18a and -20a augmented endothelial cell (EC) sprout formation. Inhibition of miR-17 and miR-20a in vivo using antagomirs significantly increased the number of perfused vessels in matrigel plugs, whereas antagomirs, that specifically target miR-18a and miR-19a were less effective. However, systemic inhibition of miR-17/20 did not affect tumor angiogenesis. Further mechanistic studies showed that miR-17/20 targets several pro-angiogenic genes. Specifically, Janus kinase 1 (Jak1) was shown to be a direct target of miR-17. In summary, we show that miR-17/20 exhibit a cell intrinsic anti-angiogenic activity in ECs. Inhibition of miR-17/20 specifically augmented neovascularization of matrigel plugs, but did not affect tumor angiogenesis indicating a context-dependent regulation of angiogenesis by miR-17/20 in vivo.
Members of the microRNA-17-92 cluster exhibit a cell-intrinsic antiangiogenic function in endothelial cells.
Specimen part
View SamplesAbout 10% of all NSCLC patients respond to gefitnib treatment and all of these patients will acquire resistance to the EGFR TKI.
Rapidly acquired resistance to EGFR tyrosine kinase inhibitors in NSCLC cell lines through de-repression of FGFR2 and FGFR3 expression.
Cell line, Treatment
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Autoregulation of Th1-mediated inflammation by twist1.
No sample metadata fields
View SamplesGene expression profiling of repeatedly activated compared to recently activated Th1 cells to identify genes that play a role in chronic inflammatory disorders and may qualify as diagnostic or therapeutic targets;
Autoregulation of Th1-mediated inflammation by twist1.
No sample metadata fields
View SamplesThe basic helix-loop-helix transcriptional repressor twist1, as an antagonist of nuclear factor B (NF-B)-dependent cytokine expression, is involved in the regulation of inflammation-induced immunopathology. We could show that twist1 is expressed by activated T helper (Th) 1 effector memory cells. Induction of twist1 in Th cells is dependent on NF-B, nuclear factor of activated T cells (NFAT), and interleukin (IL)-12 signaling via signal transducer and activator of transcription (STAT) 4. Expression of twist1 is transient following T-cell receptor engagement, and increases upon repeated stimulation of Th1 cells. Imprinting for enhanced twist1 expression is characteristic of repeatedly restimulated effector memory Th cells and thus of the pathogenic memory Th cells of chronic inflammation. Th lymphocytes from the inflamed joint or gut tissue of patients with rheumatic diseases, Crohns disease or ulcerative colitis express high levels of twist1. Expression of twist1 in Th1 lymphocytes limits the expression of the cytokines interferon-, IL-2 and tumor necrosis factor-, and ameliorates Th1-mediated immunopathology in delayed-type hypersensitivity and antigen-induced arthritis. In order to identify the effect of twist1 expression on the function of Th cells, twist1 was ectopically expressed and the transcriptome was compared to empty-virus infected control cells. In addition, this experiment allows for the identification of genes regulated by the transcription factor twist1.
Autoregulation of Th1-mediated inflammation by twist1.
No sample metadata fields
View SamplesThe targeting of oncogenic ‘driver’ kinases with small molecule inhibitors has proven to be a highly effective therapeutic strategy in selected non-small cell lung cancer (NSCLC) patients. However, acquired resistance to targeted therapies invariably arises and is a major limitation to patient care. ROS1 fusion proteins are a recently described class of oncogenic driver, and NSCLC patients that express these fusions generally respond well to ROS1-targeted therapy. In this study, we sought to determine mechanisms of acquired resistance to ROS1 inhibition. To accomplish this, we generated a ROS1 inhibition-resistant derivative of the initially sensitive NSCLC cell line HCC78.
Resistance to ROS1 inhibition mediated by EGFR pathway activation in non-small cell lung cancer.
No sample metadata fields
View SamplesAn attempt to identify small non-coding RNAs that change with increasing generations after becoming homozygous for the loss of PRG-1 Overall design: Small non-coding RNA (18-30nt) was extracted from animals the indicated number of generations after homozygosity was established
Reduced insulin/IGF-1 signaling restores germ cell immortality to Caenorhabditis elegans Piwi mutants.
Specimen part, Cell line, Subject
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Nrf2 Modulates Host Defense during Streptococcus pneumoniae Pneumonia in Mice.
Specimen part
View Samples