Test systems to identify developmental toxicants are urgently needed. A combination of human stem cell technology and transcriptome analysis was used here to provide proof-of-concept that toxicants with a related mode of action can be identified, and grouped for read-across. We chose a test system of developmental toxicity, related to the generation of neuroectoderm from pluripotent stem cells (UKN1), and exposed cells for six days to benchmark concentration (BMC) of histone deacetylase inhibitors (HDACi) valproic acid, trichostatin-A, vorinostat, belinostat, panobinostat and entinostat. To provide insight into their toxic action, we identified HDACi consensus genes, assigned them to superordinate biological processes, and mapped them to a human transcription factor network constructed from hundreds of transcriptome data sets. We also tested a heterogeneous group of mercurials (methylmercury, thimerosal, mercury(II)chloride, mercury(II)bromide, 4-chloromercuribenzoic acid, phenylmercuric acid) (BMCs). Microarray data were compared at the highest non-cytotoxic concentration for all 12 toxicants. A support vector machine (SVM)-based classifier predicted all HDACi correctly. For validation, the classifier was applied to legacy data sets of HDACi, and for each exposure situation, the SVM predictions correlated with the developmental toxicity. Finally, optimization of the classifier based on 100 probe sets showed that eight genes (F2RL2, TFAP2B, EDNRA, FOXD3, SIX3, MT1E, ETS1, LHX2) are sufficient to separate HDACi from mercurials. Our data demonstrate, how human stem cells and transcriptome analysis can be combined for mechanistic grouping and prediction of toxicants. Extension of this concept to mechanisms beyond HDACi would allow prediction of human developmental toxicity hazard of unknown compounds with the UKN1 test system.
A transcriptome-based classifier to identify developmental toxicants by stem cell testing: design, validation and optimization for histone deacetylase inhibitors.
Sex, Specimen part
View SamplesThe identification of small molecules which either increase the number and/or enhance the activity of CD34+ hematopoietic stem and progenitor cells (HSPCs) during ex-vivo expansion has remained challenging. Applying an unbiased in vivo chemical screen in a transgenic (c-myb:EGFP) zebrafish embryo model, histone deacetylase inhibitors (HDACI) (valproic acid, resminostat and entinostat) were shown to significantly amplify the number of phenotypic hematopoietic precursors. The identified HDACIs were confirmed to significantly enhance also the expansion of human HSPCs during ex vivo treatment. Long-term functionality of ex vivo expanded human HSPCs was verified in a xenotransplantation model using NSG mice. However, the HDACI induced proliferation of HSPCs was associated with short-term functional changes. One of the identified hits, valproic acid (VPA), increased the adhesion capacity of CD34+ cells on primary mesenchymal stromal cells and reduced their chemokine-mediated migration capacity in vitro. In line with the reduced migratory potential in vitro, homing as well as early engraftment of VPA treated human CD34+ cells was significantly impaired in the xenotransplantation model. Our data confirms that HDACI treatment leads to a net expansion of HSPCs cells with long-term engraftment potential across different species. However impaired homing and short-term-engraftment has to be kept in mind when designing clinical transplantation protocols. In addition, our gene expression analysis (RNA-Seq) revealed expression of several genes that were altered in CD34+ cells by VPA treatment including cell adhesion molecules and Notch and wnt genes which has been shown to be involved in preservation of stem cell properties. Overall design: Gene expression analysis of in vitro expanded human HSPCs (CD34+ cells) by valproic acid
Zebrafish In-Vivo Screening for Compounds Amplifying Hematopoietic Stem and Progenitor Cells: - Preclinical Validation in Human CD34+ Stem and Progenitor Cells.
Disease, Subject
View SamplesWe identified Ncoa3 as a regulator of neuronal morphology and microRNA activity. In order to uncover target genes of this transcriptional coactivator we performed this microarray analysis.
A large-scale functional screen identifies Nova1 and Ncoa3 as regulators of neuronal miRNA function.
Specimen part, Treatment
View SamplesLangerhans dendritic cells represent abundantly occuring and evolutionary highly conserved DCs specifically located in the stratified epithelial tissues. LCs are unique among DC family members in that they express epithelial-type adhesion molecules, allowing them to form a tight three-dimensional network in basal and suprabasal epidermal keratinocyte layers and developmentally dependent on the cytokine TGF-1. In the present study, we identified BMP-7 as another key factor inducing LC differnetiation. Here we have performed comparative analysis of highly purified CD207+/CD1a+ in vitro generated Langerhans cells in the presence of BMP-7 and TGF-1. We have identified that both BMP-7-LCs and TGF-1-LCs are closely related to each other.
Identification of bone morphogenetic protein 7 (BMP7) as an instructive factor for human epidermal Langerhans cell differentiation.
Specimen part, Treatment, Subject
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Inactivating hepatic follistatin alleviates hyperglycemia.
Sex, Specimen part
View SamplesWe compared RNA expression profiles of wild type of mice maintained on high fat diet or Irs1/2:foxo1-LTKO mice infected with Fst288 AAV-TBG virus
Inactivating hepatic follistatin alleviates hyperglycemia.
Sex, Specimen part
View SamplesTumor-associated blood vessels differ from normal vessels at the morphological and molecular level. Proteins that are only present on tumor vessels may serve as biomarkers and as therapeutic targets for inhibition of angiogenesis in cancer. Comparing the transcriptional profiles of blood vascular endothelium from human invasive bladder cancer and from normal bladder tissue, we found several markers that could serve as novel biomarkers or therapeutic targets.
Endocan is upregulated on tumor vessels in invasive bladder cancer where it mediates VEGF-A-induced angiogenesis.
Sex, Disease stage
View SamplesshRNA-mediated ablation of the RING-finger protein TRIM52 from multiple glioblastoma cell lines reduces proliferation and tumorigenesis. To identify gene signatures underlying this phenomenon, transcritional profile of TRIM52 knockdown cells was compared to control cells. Upon TRIM52 ablation, we find 278 differentially regulated genes. Gene ontology analysis reveals that many of the upregulated genes are associated with glycolysis and biosynthetic processes. Overall design: U87MG glioblastoma cells were stably transduced with doxycycline-inducible shRNA constructs targeting TRIM52 (two different shRNAs) or controls (two different non-targeting shRNAs). Knockdown was induced for five days using 2µg/ml doxycycline. shRNA expressing cells were sorted based on shRNA-coupled GFP expression via flow cytometry. mRNA sequening was performed in duplicate per shRNA cell line.
Human tripartite motif protein 52 is required for cell context-dependent proliferation.
Specimen part, Subject
View SamplesWe compared RNA expression profiles of eWAT obtained from Cntr- and LDKO-mice, and Cntr3- and LTKO-mice.
Inactivating hepatic follistatin alleviates hyperglycemia.
Sex, Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Cross-species gene expression analysis identifies a novel set of genes implicated in human insulin sensitivity.
Specimen part, Time
View Samples