Pro-inflammatory cytokines, such as tumor necrosis factor-alpha (TNFalpha) and interleukin-1beta/alpha (IL1beta/alpha) modulate catecholamine secretion, and long-term gene regulation, in chromaffin cells of the adrenal medulla. Interleukin-6 (IL6), also released during inflammation, affects transcriptional responses in primary chromaffin cells, and may coordinate immune and autonomic adrenomedullary responses via an autocrine mechanism, as TNFalpha itself strongly induces IL6 expression in chromaffin cells, which in turn express receptors responsive to IL6. We have examined the signaling mechanisms employed by IL6 to affect tyrosine hydroxylase (TH) enzymatic activation, and adrenomedullary gene transcription, in cultured bovine chromaffin cells. IL6 caused acute tyrosine/threonine phosphorylation of extracellular signal-regulated kinase 1/2 (ERK1/2), and serine phosphorylation of signal transducer and activator of transcription 3 (STAT3), as do several other first messengers acting on the chromaffin cell, including histamine, nicotine and angiotensin II. IL6 uniquely activated tyrosine phosphorylation of STAT3. Consistent with a short-term ERK1/2 activation, IL6 treatment caused prompt regulation of TH phosphorylation, and up-regulation of genes encoding secreted proteins of the adrenal medulla including galanin, vasoactive intestinal peptide (VIP), gastrin releasing peptide (GRP) and parathyroid hormone-like hormone (PTHLH). We further examined the effects of IL6 treatment on the entire bovine chromaffin cell transcriptome. Of 90 genes up-regulated by IL6, only 16 of which are known targets of IL6 in the immune system. The remaining genes likely represent a combination of novel IL6/STAT3 targets, targets of ERK1/2 shared by other first messengers, and, potentially, IL6-dependent genes activated in a secondary cascade via transcription mediated by IL6-induced transcription factors, such as HIF-1alpha. Notably, genes induced by IL6 represent a cohort with a profile that includes both neuroendocrine-specific genes, including several that are activated by G-protein couple receptor (GPCR) signaling pathways initiated by histamine and pituitary adenylate cyclase-activating polypeptide (PACAP), and some transcripts also activated by cytokines including interferon-alpha (INFalpha and TNFalpha. These results suggest an integrative role for IL6 in overall fine-tuning of the chromaffin cell response to a wide range of physiological and paraphysiological stressors, particularly when immune and endocrine stimuli converge in the adrenal medulla.
Interleukin-6-mediated signaling in adrenal medullary chromaffin cells.
Specimen part
View SamplesThe steroid hormone aldosterone plays a role in vascular function and disease. Aldosterone activates the mineralocorticoid receptor (MR), a ligand-activated transcription factor. MR have been found to be expressed in vascular cells and vessels.
Placental growth factor mediates aldosterone-dependent vascular injury in mice.
Sex, Specimen part
View SamplesBackground and aims: There are considerable evidences demonstrating that angiogenesis and chronic inflammation are mutually dependent. However, although cirrhosis progression is characterized with a chronic hepatic inflammatory process, this connection is not sufficiently explored as a therapeutic strategy. Therefore, this study was aimed to assess the potential benefits of targeting angiogenesis in cirrhotic livers to modulate inflammation and fibrosis. For this purpose, we evaluate the therapeutic utility of angiogenesis inhibitors. Methods: The in vivo effects of angiogenesis inhibitors were monitored in liver of cirrhotic rats by measuring angiogenesis, inflammatory infiltrate, fibrosis, a-smooth muscle actin (a-SMA) accumulation, differential gene expression (by microarrays), and portal pressure. Results: Cirrhosis progression was associated with a significant enhancement of vascular density and expression of vascular endothelial growth factor-A (VEGF-A), angiopoietin-1, angiopoietin-2 and placental growth factor (PlGF) in cirrhotic livers. The newly formed hepatic vasculature expressed vascular cell adhesion molecule-1 (VCAM-1) and intercellular adhesion molecule-1 (ICAM-1). Interestingly, the expression of these adhesion molecules correlated well with local inflammatory infiltrate. Livers of cirrhotic rats treated with angiogenesis inhibitors presented a significant decrease in hepatic vascular density, inflammatory infiltrate, a-SMA abundance, collagen expression and portal pressure. Conclusion: Angiogenesis inhibitors may offer a potential novel therapy for cirrhosis due to its multiple mechanisms of action against angiogenesis, inflammation and fibrosis in cirrhotic livers.
Antiangiogenic treatment with sunitinib ameliorates inflammatory infiltrate, fibrosis, and portal pressure in cirrhotic rats.
No sample metadata fields
View SamplesERG (Ets Related Gene) is an ETS transcription factor that was originally described for its role in a number of human cancers. Our preliminary data demonstrate that ERG exhibits a highly EC restricted pattern of expression in cultured primary cells and several adult tissues including the heart, lung, and brain. In response to inflammatory stimuli, such as TNF-alpha, we observed a marked reduction of ERG expression in EC.
Antiinflammatory effects of the ETS factor ERG in endothelial cells are mediated through transcriptional repression of the interleukin-8 gene.
Cell line
View SamplesUntreated HIV-1 infection progresses through acute and asymptomatic stages to AIDS. While each of the three stages has well-known clinical, virologic and immunological characteristics, much less is known of the molecular mechanisms underlying each stage. Here we report lymphatic tissue microarray analyses revealing for the first time stage-specific patterns of gene expression during HIV-1 infection. We show that while there is a common set of key genes with altered expression throughout all stages, each stage has a unique gene-expression signature. The acute stage is most notably characterized by increased expression of hundreds of genes involved in immune activation, innate immune defenses (e.g.MDA-5, TLR-7 and -8, PKR, APOBEC3B, 3F, 3G), adaptive immunity, and in the pro-apoptotic Fas-Fas-L pathway. Yet, quite strikingly, the expression of nearly all acute-stage genes return to baseline levels in the asymptomatic stage, accompanying partial control of infection. In the AIDS stage, decreased expression of numerous genes involved in T cell signaling identifies genes contributing to T cell dysfunction. These common and stage-specific, gene-expression signatures provide new insights into the molecular mechanisms underlying the host response and the slow, natural course of HIV-1 infection.
Microarray analysis of lymphatic tissue reveals stage-specific, gene expression signatures in HIV-1 infection.
Sex, Age, Specimen part, Disease, Disease stage, Race, Subject
View SamplesHypermethylation of tumor suppressor gene (TSG) promoters confers growth advantages to cancer cells, but how these changes arise is poorly understood. Here, we report that tumor hypoxia reduces the activity of oxygen-dependent TET enzymes, which catalyze DNA de-methylation through 5-methylcytosine oxidation. This occurs independently of hypoxia-associated alterations in TET gene expression, basal metabolism, HIF activity or nuclear reactive oxygen species, but directly depends on oxygen shortage. Hypoxia-induced loss of TET activity increases hypermethylation at gene promoters in vitro, while also in patients, gene promoters are markedly more methylated in hypoxic than normoxic tumors. Affected genes are frequently involved in DNA repair, cell cycle regulation, angiogenesis and metastasis, indicating cellular selection of hypermethylation events. Overall, up to 50% of the tumor-associated hypermethylation is ascribable to hypoxia across various cancer types. Accordingly, spontaneous murine breast tumors become hypermethylated when rendered hypoxic through vessel pruning, whereas vessel normalisation rescues this effect. Tumor hypoxia thus acts as a novel regulator underlying DNA methylation. Overall design: RNAseq of MCF7 cells grown under hypoxic and normoxic conditions. Submission includes data on 5 independent RNAseq experiments, each containing biological replicates grown under hypoxic conditions (0.5% oxygen), and under normoxic conditions.
Tumour hypoxia causes DNA hypermethylation by reducing TET activity.
Subject
View SamplesRegulatory T (Treg) cell activation and expansion during neonatal life and in response to inflammation are critical for immunosuppression, yet the mechanisms governing these events are incompletely understood. We report that the oncogene and transcriptional regulator c-Myc (Myc) controls immune homeostasis through regulation of Treg cell accumulation and functional activation. Myc activity is enriched in Treg cells generated during neonatal life and responding to inflammation. Myc-deficient Treg cells show cell-intrinsic defects in overall accumulation and ability to transition to an activated state during early life or acute inflammation. Consequently, loss of Myc in Treg cells results in a rapid, early-onset autoimmune disorder accompanied by uncontrolled effector CD4+ and CD8+ T cell responses. We also provide evidence that Myc regulates mitochondrial oxidative metabolism but is dispensable for fatty acid oxidation (FAO). Indeed, Treg cell-specific deletion of Cox10, which is required for oxidative phosphorylation, but not Cpt1a, the rate-limiting enzyme for FAO, results in impaired Treg cell function and maturation. Thus, Myc coordinates Treg cell accumulation, transitional activation and metabolic programming to orchestrate immune homeostasis.
Homeostasis and transitional activation of regulatory T cells require c-Myc.
Specimen part
View SamplesAXL is activated by its ligand GAS6 and is expressed in triple-negative breast cancer cells. We report that AXL is also detected in HER2+ breast cancer specimens where its expression correlates with poor patients' survival. Using murine models of HER2+ breast cancer, AXL, but not Gas6, was found essential for metastasis. We determined that AXL is required for intravasation, extravasation and growth at the metastatic site. AXL is expressed in HER2+ cancers displaying EMT signatures and contributes to sustain EMT in murine tumors. Interfering with AXL in patient-derived xenograft impaired TGF-ß-induced cell invasion. Lastly, pharmacological inhibition of AXL decreased the metastatic burden of mice developing HER2+ breast cancer. Our data identify AXL as a potential co-therapeutic target during the treatment of HER2+ breast cancers to limit metastasis. Overall design: Differential gene expression profile between tumor grafts of AXL-/- and AXL+/+ cells in FVB mice by RNA sequencing (Illumina HiSEq 2000)
The Receptor Tyrosine Kinase AXL Is Required at Multiple Steps of the Metastatic Cascade during HER2-Positive Breast Cancer Progression.
Specimen part, Cell line, Subject
View SamplesAXL is activated by its ligand GAS6 and is expressed in triple-negative breast cancer cells. We report that AXL is also detected in HER2+ breast cancer specimens where its expression correlates with poor patients' survival. Using murine models of HER2+ breast cancer, AXL, but not Gas6, was found essential for metastasis. We determined that AXL is required for intravasation, extravasation and growth at the metastatic site. AXL is expressed in HER2+ cancers displaying EMT signatures and contributes to sustain EMT in murine tumors. Interfering with AXL in patient-derived xenograft impaired TGF-ß-induced cell invasion. Lastly, pharmacological inhibition of AXL decreased the metastatic burden of mice developing HER2+ breast cancer. Our data identify AXL as a potential co-therapeutic target during the treatment of HER2+ breast cancers to limit metastasis. Overall design: Differential gene expression profile between MMTV-Neu tumors of AXL-/- and AXL+/+ by RNA sequencing (Illumina HiSEq 2000)
The Receptor Tyrosine Kinase AXL Is Required at Multiple Steps of the Metastatic Cascade during HER2-Positive Breast Cancer Progression.
Specimen part, Cell line, Subject
View SamplesTranscriptional profile of control and VEGF overexpressing FACS-isolated CD34+ Cancer stem cells from DMBA/TPA induced skin tumours
A vascular niche and a VEGF-Nrp1 loop regulate the initiation and stemness of skin tumours.
No sample metadata fields
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