Carbon nanotubes (CNTs) are fibrous particulates made up of elemental carbon and a novel nanomaterial known for its variety of industrial applications. It has been shown that lung exposure to CNTs may cause adverse effects inclunding lung inflammation and remodeling in experimental models. We investigated the impact of genetic background on the development of adverse outcomes by comparing several common inbred mouse strains and found that C57Bl/6 and DBA/2 strains were polarized in their sensitivity to adverse changes at 4 weeks following an exposure to 4 mg/kg CNT. Here we compare underlying gene expression profiles which may inform the understanding of lung biology underpinning genetic susceptibility to adverse outcomes following environmental or occupational exposure to CNTs. Overall design: Changes in mRNA profiles were compared between CNT-exposed animals and vehicle-treated controls (n=3/group) of either C57Bl/6 or DBA/2 strains.
Genetic susceptibility to toxicologic lung responses among inbred mouse strains following exposure to carbon nanotubes and profiling of underlying gene networks.
Specimen part, Subject
View SamplesThe aryl hydrocarbon receptor (AHR) is a ligand activated transcription factor that regulates the expression of xenobiotic detoxification genes and is a critical mediator of gene-environment interactions. In addition, many AHR target genes that have been identified by genome-wide profiling have morphogenetic functions, suggesting that AHR activation may play a role in embryonic development. To address this hypothesis, we studied the consequences of AHR activation by TCDD, its prototypical ligand, during spontaneous mouse ES cell differentiation into contractile cardiomyocytes. Treatment with TCDD or shRNA-mediated AHR knockdown significantly decreased the ability of cardiomyocytes to contract and the expression of cardiac markers in these cells. An AHR-positive embryonic stem cell lineage was generated that expressed puromycin resistance and eGFP under the control of the AHR-responsive Cyp1a1 promoter. Cells of this lineage were over 90% pure and expressed AHR as well as cardiomyocyte markers. Analysis of temporal trajectories of global gene expression in these cells shows that activation of the AHR/TCDD axis disrupts the concerted expression of genes that regulate multiple signaling pathways involved in cardiac and neural morphogenesis and differentiation, including dozens of genes encoding homeobox transcription factors and Polycomb and Trithorax Group genes. More than 50% of the homeobox factors so regulated do not have AhRE sites in their promoters, indicating that AHR activation may establish a complex regulatory network that reaches beyond direct AHR signaling and is capable of disrupting various aspects of embryonic development, including cardiomyocyte differentiation. Overall design: mRNA profiles of WT and selected AHR positive cells at different differentiation days treated with and without TCDD in duplicates
Disruption of aryl hydrocarbon receptor homeostatic levels during embryonic stem cell differentiation alters expression of homeobox transcription factors that control cardiomyogenesis.
Treatment, Subject
View SamplesEndothelin-1 (ET-1) plays a critical role in connective tissue remodeling by fibroblasts during tissue repair and fibrosis. We investigated the molecular pathways in the transmission of ET-1 signals that lead to features of connective tissue remodeling, in particular the role of FAK (focal adhesion kinase).
Inhibition of focal adhesion kinase prevents experimental lung fibrosis and myofibroblast formation.
Specimen part, Treatment
View SamplesInhibition of mTOR signaling using the rapalog everolimus is an FDA-approved targeted therapy for patients with lung and gastroenteropancreatic neuroendocrine tumors (NET). However, patients eventually progress on treatment, highlighting the need for additional therapies. We focused on pancreatic NETs (pNETs) and reasoned that treatment of these tumors upon progression on rapalog therapy, with an mTOR kinase inhibitor (mTORKi) such as CC-223 could overcome a number of resistance mechanisms in tumors and delay cardiac carcinoid disease. We performed preclinical studies using human pNET cells in vitro and injected them subcutaneously or orthotopically to determine tumor progression and cardiac function in mice treated with either rapamycin alone or switched to CC-223 upon progression. Detailed signaling and RNA sequencing analyses were performed on tumors that were sensitive or progressed on mTOR treatment. Approximately 57% of mice bearing pNET tumors which progressed on rapalog therapy showed a significant decrease in tumor volume upon a switch to CC-223. Moreover, mice treated with an mTORKi exhibited decreased cardiac dilation and thickening of heart valves than those treated with placebo or rapamycin alone. In conclusion, in the majority of pNETs that progress on rapalogs, it is possible to reduce disease progression using an mTORKi, such as CC-223. Moreover, CC-223 had an additional transient cardiac benefit on valvular fibrosis compared to placebo- or rapalog-treated mice. These results provide the preclinical rationale to further develop mTORKi clinically upon progression on rapalog therapy and to further test their long term cardioprotective benefit in those NET patients prone to carcinoid syndrome. Overall design: We performed RNA sequencing analyses as an unbiased means to assess changes in gene expression. Our major goal was to identify the differences in tumor mRNAs between the CC-223- and non-CC-223 responders compared to the rapamycin alone treatment arm (Fig 5A in Orr-Asman et al manuscript). The analysis was conducted using 1 tumor each from 13 and 14 mice treated with rapamycin or switched to CC-223 respectively.
mTOR Kinase Inhibition Effectively Decreases Progression of a Subset of Neuroendocrine Tumors that Progress on Rapalog Therapy and Delays Cardiac Impairment.
Specimen part, Subject
View SamplesIn an accompanying paper we found specific localization of diabetogenic T cells only to islets of Langerhans bearing the specific antigen. Instrumental in the specific localization was the presence of intra-islet dendritic cells bearing the -cell-peptide-MHC complex. Here we report that the entry of diabetogenic CD4 T cells very rapidly triggered inflammatory gene expression changes in islets and vessels by up-regulating chemokines and adhesion molecules. VCAM-1 expression was notable in blood vessels and so was ICAM-1. ICAM-1 was also found on -cells. These expression changes induced the entry of non-specific T cells that otherwise did not localize to the islets. In contrast to the entry of diabetogenic CD4 T cells, the entrance of non-specific T cells required a chemokine response and VCAM-1 expression by the islets. Interferon-gamma was important for the early gene expression changes in the islets. By microarray analysis we detected up-regulation of a group of interferon-inducible genes as early as 8 hours post T cell transfer. These studies provide a baseline to examine the development of therapeutics that can modulate islet localization of diabetogenic T cells to control this autoimmune disease.
Entry of diabetogenic T cells into islets induces changes that lead to amplification of the cellular response.
Specimen part
View Samplesp63 is critical for epithelial development yet little is known about the transcriptional programmes it regulates. The p63 transactivating (TA) isoforms contain an amino-terminal exon that encodes a p53-like transactivation domain, whereas N-isoforms lack this domain but contain the common DNA binding domain (DBD), suggesting that TAp63 and Np63 isoforms may have opposing functions. By characterising transcriptional changes and cellular effects following modulation of p63 expression, we have defined a vital role for p63 in cellular adhesion. Knockdown of p63 expression caused downregulation of cell adhesion-associated genes, cell detachment and anoikis in mammary epithelial cells and keratinocytes. Conversely, overexpression of the TAp63 or Np63 isoforms of p63 upregulated cell adhesion molecules, increased cellular adhesion and conferred resistance to anoikis.
p63 regulates an adhesion programme and cell survival in epithelial cells.
Cell line
View SamplesWe used microarrays to unveil the gene expression alterations upon short-term HFD administration
Dietary alterations modulate susceptibility to Plasmodium infection.
Specimen part
View SamplesType 1 diabetes (T1D) is an autoimmune disease triggered by T cell reactivity to protein antigens produced by the -cells. Here we present a chronological compendium of transcriptional profiles from islets of Langerhans isolated from non-obese diabetic (NOD) mice ranging from 2 wks up to diabetes and compared to controls. Parallel analysis was made of cellular components of the islets. Myeloid cells populated the islets early during development in all mouse strains. This was followed by a type I interferon signature detectable at 4-6 wks of age only in diabetes susceptible mice. Concurrently, CD4 T cells were found within islets, many in contact with intra-islet antigen presenting cells. Early cellular signs of islet reactivity were detected by six wks. By 8 wks, NOD islets contained all major leukocytes populations and an inflammatory gene signature. This work establishes the natural transcriptional signature of T1D and provides a resource for future research.
Defining the transcriptional and cellular landscape of type 1 diabetes in the NOD mouse.
Specimen part
View SamplesBackground: Inter-patient prostate cancer (PrCa) heterogeneity results in highly variable patient outcomes. Multi-purpose biomarkers to dissect this heterogeneity are urgently required to improve treatment and accelerate drug development in PrCa. Circulating biomarkers are most practical for evaluating this disease. We pursued the analytical validation and clinical qualification of blood mRNA expression arrays.
Prognostic value of blood mRNA expression signatures in castration-resistant prostate cancer: a prospective, two-stage study.
Subject
View SamplesMM1.S cells stably transduced with control or b-catenin shRNA were established. Total RNA was isolated from 5x 10^6 cells of each in triplicate.
Aurora kinase A is a target of Wnt/beta-catenin involved in multiple myeloma disease progression.
Cell line
View Samples