Unlike other terminally differentiated cell types, vascular SMCs display remarkable phenotypic plasticity. The adult, differentiated state is traditionally defined by expression of well-characterized SMC contractile genes. Extracellular cues, however, can induce contractile SMCs to remodel toward a synthetic state characterized by a spectrum of proliferative, migratory, and inflammatory phenotypes.
Integrative genomics identifies DSCR1 (RCAN1) as a novel NFAT-dependent mediator of phenotypic modulation in vascular smooth muscle cells.
Specimen part
View SamplesElevated levels of androgen receptor (AR) in prostate cancer confer resistance to current antiandrogens and play a causal role in disease progression due to persistent target gene activation. Through pharmacologic and genetic approaches, we show that half of all direct AR target genes, including TMPRSS2, the primary driver of ETS fusion transcripts in 70 percent of human prostate cancers, require histone deacetylase (HDAC) activity for transcriptional activation by AR. Surprisingly, the HDAC3-NCoR complex, which typically functions to repress gene expression by nuclear receptors, is required for AR target gene activation. Prostate cancer cells treated with HDAC inhibitors have reduced AR protein levels, but we show that the mechanism of blockade of AR activity is through failure to assemble a coactivator/RNA polymerase II complex after AR binds to the enhancers of target genes. Failed complex assembly is associated with a phase shift in the cyclical wave of AR recruitment that typically occurs in response to ligand treatment. HDAC inhibitors retain the ability to block AR activity in hormone refractory prostate cancer models and therefore merit clinical investigation in this setting. HDAC-regulated AR target genes defined here can serve as biomarkers to ensure sufficient levels of HDAC inhibition.
Histone deacetylases are required for androgen receptor function in hormone-sensitive and castrate-resistant prostate cancer.
No sample metadata fields
View SamplesElevated levels of androgen receptor (AR) in prostate cancer confer resistance to current antiandrogens and play a causal role in disease progression due to persistent target gene activation. Through pharmacologic and genetic approaches, we show that half of all direct AR target genes, including TMPRSS2, the primary driver of ETS fusion transcripts in 70 percent of human prostate cancers, require histone deacetylase (HDAC) activity for transcriptional activation by AR. Surprisingly, the HDAC3-NCoR complex, which typically functions to repress gene expression by nuclear receptors, is required for AR target gene activation. Prostate cancer cells treated with HDAC inhibitors have reduced AR protein levels, but we show that the mechanism of blockade of AR activity is through failure to assemble a coactivator/RNA polymerase II complex after AR binds to the enhancers of target genes. Failed complex assembly is associated with a phase shift in the cyclical wave of AR recruitment that typically occurs in response to ligand treatment. HDAC inhibitors retain the ability to block AR activity in hormone refractory prostate cancer models and therefore merit clinical investigation in this setting. HDAC-regulated AR target genes defined here can serve as biomarkers to ensure sufficient levels of HDAC inhibition.
Histone deacetylases are required for androgen receptor function in hormone-sensitive and castrate-resistant prostate cancer.
No sample metadata fields
View SamplesWe used microarrays to detail the global gene expression changes following apical infection of porcine choroid plexus epithelial cells (PCPEC) with Streptococcus suis (S. suis)
In vitro transcriptome analysis of porcine choroid plexus epithelial cells in response to Streptococcus suis: release of pro-inflammatory cytokines and chemokines.
Specimen part
View SamplesDevelopmental neurotoxicity (DNT) may be induced when chemicals disturb a key neurodevelopmental process, and many tests focus on this type of toxicity. Alternatively, DNT may occur when chemicals are cytotoxic only during a specific neurodevelopmental stage. The toxicant sensitivity is affected by the expression of toxicant targets and by resilience factors. Although cellular metabolism plays an important role, little is known how it changes during human neurogenesis, and how potential alterations affect toxicant sensitivity of mature vs. immature neurons. We used immature (d0) and mature (d6) LUHMES cells (dopaminergic human neurons) to provide initial answers to these questions. Transcriptome profiling and characterization of energy metabolism suggested a switch from predominantly glycolytic energy generation to a more pronounced contribution of the tricarboxylic acid cycle (TCA) during neuronal maturation. Therefore, we used pulsed stable isotope-resolved metabolomics (pSIRM) to determine intracellular metabolite pool sizes (concentrations), and isotopically non-stationary 13C-metabolic flux analysis (INST 13C MFA) to calculate metabolic fluxes. We found that d0 cells mainly use glutamine to fuel the TCA. Furthermore, they rely on extracellular pyruvate to allow continuous growth. This metabolic situation does not allow for mitochondrial or glycolytic spare capacity, i.e. the ability to adapt energy generation to altered needs. Accordingly, neuronal precursor cells displayed a higher sensitivity to several mitochondrial toxicants than mature neurons differentiated from them. In summary, this study shows that precursor cells lose their glutamine dependency during differentiation while they gain flexibility of energy generation and thereby increase their resistance to low concentrations of mitochondrial toxicants.
Stage-specific metabolic features of differentiating neurons: Implications for toxicant sensitivity.
Sex, Specimen part, Time
View SamplesThe aim of reprotoxicity testing is to reveal adverse effects of chemicals and drugs on reproduction and on pre and postnatal fetal development. There is very limited data available on gene expression profiling for elucidation of the teratogenic effects of nongenotoxic teratogens. Therefore, research was undertaken to obtain knowledge on the molecular effects of MSC1096199 (previously known as EMD 82571), a calcium sensitizer that was abandoned in the preclinical development phase due to its teratogenic effects in some foetuses. Pregnant wistar rats were dose daily with either MSC1096199 (50 or 150 mg/kg) or Retinoic acid (12 mg/kg) on gestational days 6-17. Microarray experiment were performed using four different tissues (maternal liver, embryo liver (GD20), embryo bone (GD20), and whole embryo (GD12)) under four different conditions (vehicle, low dose and high dose of MSC1096199 and Retinoic acid) to determine the drug regulated genes. In the high dose treatment group, approximately 58% of the fetuses showed malformations i.e. exencephaly and agnathia, and toxicogenomics evidenced that the genes critically involved in osteogenesis, odontogenesis and extra cellular matrix components to be significantly regulated by MSC1096199, therefore providing a molecular rational for the observed teratogenic effects.
A rat toxicogenomics study with the calcium sensitizer EMD82571 reveals a pleiotropic cause of teratogenicity.
Specimen part, Treatment
View SamplesConjugated linoleic acid (CLA), a class of fatty acids found in beef and dairy products, has been shown to inhibit tumorigenesis in a variety of cancer model systems. Based on previously well-documented anti-tumor activity of CLA in rodent models of breast cancer, a pilot study was initiated to examine the effect of dietary CLA in a well-established transgenic model of breast cancer. Western blots were performed for the detection of AKT, c-Src, ERK1/2, and Cdc24. CLA significantly increased tumor burden (p<0.1) independent of an increase in oncogenic signaling. Mammary gland whole mounts indicated a loss of mammary adipose and extensive epithelial expansion in CLA-treated animals. Microarray analysis indicated a significant reduction in cytoskeletal related genes with at least a two-fold decrease in five out of six CLA-fed animals compared to untreated controls. Reduction of Cdc42, a key regulator of cell adhesion and cytoskeletal arrangements, was confirmed at the protein level by western blot (p<0.01). These findings suggest that dietary CLA may advance the malignant phenotype by promoting a loss of cell polarity and adhesion in the mammary gland epithelium. This action may have serious clinical implications for a subset high-risk population and warrants further investigation.
Pilot study on the effects of dietary conjugated linoleic acid on tumorigenesis and gene expression in PyMT transgenic mice.
Sex, Age, Specimen part
View SamplesTranscriptome of HEK and B cells were analyzed by microarray and RNA-Seq parallely. Both platforms were then compared in terms of sensitivity. To assess whether values were a reliable indicator of gene activity, we correlated these values with hypophosphorylated RNA polymerase II (PolIIa) occupancy, used as a landmark of transcription initiation. For HEK, we identified PolIIa islands by chromatin immunoprecipitation and sequencing (ChIP-Seq).
A global view of gene activity and alternative splicing by deep sequencing of the human transcriptome.
No sample metadata fields
View SamplesMalignant epithelia and tumor-associated stroma of PABC and Non-PABC were isolated by laser capture microdissection and gene expression profiled. Additionally, normal breast epithelia and stroma adjacent to the two tumor types were profiled.
Genomic signatures of pregnancy-associated breast cancer epithelia and stroma and their regulation by estrogens and progesterone.
Specimen part, Subject
View SamplesHematopoietic stem cells (HSCs) primarily reside in the bone marrow where signals generated by stromal cells regulate their self-renewal, proliferation, and trafficking. Endosteal osteoblasts and perivascular stromal cells including endothelial cells3, CXCL12-abundant reticular (CAR) cells, leptin-receptor positive stromal cells, and nestin-GFP positive mesenchymal progenitors have all been implicated in HSC maintenance. However, it is unclear if specific hematopoietic progenitor cell (HPC) subsets reside in distinct niches defined by the surrounding stromal cells and the regulatory molecules they produce. CXCL12 (stromal-derived factor-1, SDF-1) regulates both HSCs and lymphoid progenitors and is expressed by all of these stromal cell populations.
CXCL12 in early mesenchymal progenitors is required for haematopoietic stem-cell maintenance.
Specimen part
View Samples