41 volunteers (male non-smokers) were exposed to formaldehyde (FA) vapors for 4 h per day over a period of 5 working days under strictly controlled conditions. For each exposure day, different exposure concentrations were used in a random order ranging from 0 up to 0.7 ppm. At concentrations of 0.3 ppm and 0.4 ppm, four peaks of 0.6 or 0.8 ppm for 15 min each were applied. During exposure, subjects had to perform bicycle exercises (about 80 W) four times for 15 min. Blood samples, exfoliated nasal mucosa cells and nasal biopsies were taken before the first and after the last exposure. Nasal epithelial cells were additionally sampled 1, 2 and 3 weeks after the end of the exposure period. The alkaline comet assay, the sister chromatid exchange (SCE) test and the cytokinesis-block micronucleus test (CBMNT) were performed with blood samples. The micronucleus test (MNT) was also performed with exfoliated nasal mucosa cells. The expression (mRNA level) of the GSH-dependent formaldehyde dehydrogenase (FDH, identical to alcohol dehydrogenase 5; ADH5; EC 1.2.1.46) was measured in blood samples by quantitative real-time RT-PCR with TaqMan probes. DNA microarray analyses using a full-genome human microarray were performed on blood samples and nasal biopsies of selected subgroups with the highest FA exposure at different days. None of the tests performed showed a biologically significant effect related to FA exposure. Under the experimental conditions of this study, inhalation of FA did not lead to genotoxic effects in peripheral blood cells and nasal mucosa and had no effect on the expression of the FDH gene. Inhalation of FA also did not cause biologically relevant alterations in the expression of genes in a microarray analysis with nasal biopsies and peripheral blood cells.
Assessment of genotoxic effects and changes in gene expression in humans exposed to formaldehyde by inhalation under controlled conditions.
Sex, Specimen part, Treatment, Subject
View SamplesWe analysed the genexpression of dental follicle cells (DFCs) after 3 days osteogenic differentiation with BMP2 after transfection with a DLX3 plasmid (pDLX3) and after transfection with an empty plasmid (pEV)
A protein kinase A (PKA)/β-catenin pathway sustains the BMP2/DLX3-induced osteogenic differentiation in dental follicle cells (DFCs).
Specimen part
View SamplesThe goal of the experiment: To characterize the dynamic gene expression profile of engineered human skin in vitro and after grafting, and compare with expression profile of uninjured human skin.
Engineered human skin substitutes undergo large-scale genomic reprogramming and normal skin-like maturation after transplantation to athymic mice.
Specimen part
View SamplesMCF7 and BT474 cell lines were exposed to LTED culture for 0 and 2 days, 6 weeks and 10 months and monitored for changes in gene expression
Clinical instability of breast cancer markers is reflected in long-term in vitro estrogen deprivation studies.
Cell line, Treatment, Time
View SamplesExternal stimulations of cells by hormones, growth factors or cytokines activate signal transduction pathways that subsequently induce a rearrangement of cellular gene expression. The representation and analysis of changes in the gene response is complicated, and essentially consists of multiple layered temporal responses. In such situations, matrix factorization techniques may provide efficient tools for the detailed temporal analysis. Related methods applied in bioinformatics intentionally do not take prior knowledge into account. In signal processing, factorization techniques incorporating data properties like second-order spatial and temporal structures have shown a robust performance. However, large-scale biological data rarely imply a natural order that allows the definition of an autocorrelation function. We therefore develop the concept of graph-autocorrelation. We encode prior knowledge like transcriptional regulation, protein interactions or metabolic pathways as a weighted directed graph. By linking features along this underlying graph, we introduce a partial ordering of the samples to define an autocorrelation function. Using this framework as constraint to the matrix factorization task allows us to set up the fast and robust graph decorrelation (GraDe) algorithm. To analyze the alterations in the gene response in IL-6 stimulated primary mouse hepatocytes by GraDe, a time-course microarray experiment was performed. Extracted gene expression profiles show that IL-6 activates genes involved in cell cycle progression and cell division in a time-resolved manner. On the contrary, genes linked to metabolic and apoptotic processes are down-regulated indicating that IL-6 mediated priming rendered hepatocytes more responsive towards cell proliferation and reduces expenses for the energy household.
Knowledge-based matrix factorization temporally resolves the cellular responses to IL-6 stimulation.
Specimen part, Treatment, Time
View SamplesThis SuperSeries is composed of the SubSeries listed below.
An immediate-late gene expression module decodes ERK signal duration.
Specimen part, Cell line
View SamplesWe integrate experimental data and mathematical modelling to unveil how ERK signal duration is relayed to mRNA dynamics.
An immediate-late gene expression module decodes ERK signal duration.
Cell line
View SamplesType I interferons (IFN) are important components of the innate antiviral response. A key signalling pathway activated by IFNa is the Janus kinase signal transducer and activator of transcription (JAKSTAT) pathway. Major components of the pathway have been identified. However, critical kinetic properties that facilitate accelerated initiation of intracellular antiviral signalling and thereby promote virus elimination remain to be determined. By combining mathematical modelling with experimental analysis, we show that control of dynamic behaviour is not distributed among several pathway components but can be primarily attributed to interferon regulatory factor 9 (IRF9), constituting a positive feedback loop. Model simulations revealed that increasing the initial IRF9 concentration reduced the time to peak, increased the amplitude and enhanced termina- tion of pathway activation. These model predictions were experimentally verified by IRF9 over-expression studies. Furthermore, acceleration of signal processing was linked to more rapid and enhanced expression of IFNa target genes. Thus, the amount of cellular IRF9 is a crucial determinant for amplification of early dynamics of IFNa-mediated signal transduction.
Combining theoretical analysis and experimental data generation reveals IRF9 as a crucial factor for accelerating interferon α-induced early antiviral signalling.
Specimen part, Disease, Cell line, Time
View SamplesThis SuperSeries is composed of the SubSeries listed below.
TTCA: an R package for the identification of differentially expressed genes in time course microarray data.
Cell line, Treatment
View SamplesThe oncogenic mechanisms and tumour biology underpinning Clear Cell Sarcoma of Kidney (CCSK), the second commonest paediatric renal malignancy, are poorly understood and currently therapy depends heavily on Doxorubicin with cardiotoxic side-effects. Previously, we characterised the balanced t(10;17)(q22;p13) chromosomal translocation, identified at that time as the only recurrent genetic aberration in CCSK. This translocation results in an in-frame fusion of the YWHAE (encoding 14-3-3e) and NUTM2 genes, with a somatic incidence of 12%. Clinico-pathological features of that cohort suggested that this aberration might be associated with higher stage and grade disease. Since no primary CCSK cell line exists, we generated various stably transfected cell lines containing doxycycline-inducible HA-tagged-YWHAE-NUTM2, in order to study the effect of expressing this transcript. 14-3-3e-NUTM2-expressing cells exhibited significantly greater cell migration compared to mock-treated controls. Gene and protein expression studies conducted in parallel on this model system suggested dysregulation of signalling pathways as a basis to the migration changes. Importantly, by blocking these signalling pathways using anti-EGFR, anti-IGF1R and anti-PDGFa neutralising antibodies, the migratory advantage conferred by transcript expression was abrogated. These results support 14-3-3e-NUTM2 expression as a contributor to CCSK tumorigenesis and provide avenues for the exploration of novel therapeutic approaches in CCSK.
Dysregulated mitogen-activated protein kinase signalling as an oncogenic basis for clear cell sarcoma of the kidney.
Disease, Cell line
View Samples