The current test strategy for carcinogenicity is generally based on in vitro and in vivo genotoxicity assays. Non-genotoxic carcinogens (NGTXC) are negative for genotoxicity and go undetected. Therefore, alternative tests to detect these chemicals are urgently needed. NGTXC act through different modes of action, which complicates the development of such assays. We have demonstrated recently in primary mouse hepatocytes that some, but certainly not all, NGTXC can be categorized according to their mode of action based on feature detection at a gene expression level (Schaap et al. 2012, PMID22710402). Identification of a wider range of chemicals probably requires multiple in vitro systems. In the current study we describe the added value of using mouse embryonic stem cells. In this study the focus is on NGTXC, but we also included genotoxic carcinogens and non-carcinogens. This approach enables us to assess the robustness of this method and to evaluate the system for recognizing features of chemicals in general, which is important for application in future risk assessment.
A novel toxicogenomics-based approach to categorize (non-)genotoxic carcinogens.
Specimen part
View SamplesA mucus layer covers and protects the intestinal epithelial cells from direct contact with microbes. This mucus layer not only prevents inflammation but also plays an essential role in microbiota colonization, indicating the complex interplay between mucus composition-microbiota and intestinal health. However, it is unknown whether the mucus layer is influenced by age or sex and whether this contributes to reported differences in intestinal diseases in males and females or with ageing. Therefore, in this study we investigated the effect of age on mucus thickness, intestinal microbiota composition and immune composition in relation to sex. The ageing induced shrinkage of the colonic mucus layer was associated with bacterial penetration and direct contact of bacteria with the epithelium in both sexes. Additionally, several genes involved in the biosynthesis of mucus were downregulated in old mice, especially in males, and this was accompanied by a decrease in abundances of various Lactobacillus species and unclassified Clostridiales type IV and XIV and increase in abundance of the potential pathobiont Bacteroides vulgatus. The changes in mucus and microbiota in old mice were associated with enhanced activation of the immune system as illustrated by a higher percentage of effector T cells in old mice. Our data contribute to a better understanding of the interplay between mucus-microbiota-and immune responses and ultimately may lead to more tailored design of strategies to modulate mucus production in targeted groups.
The effect of age on the intestinal mucus thickness, microbiota composition and immunity in relation to sex in mice.
Sex, Age, Specimen part
View SamplesBackground: Antimalarials have anticancer potential. Results: We have systematically tested five distinct antimalaria drugs in a panel of cancer cell lines. Conclusion: Three antimalarial classes display potent antiproliferative activity, and their potency is correlated with cancer cell gene expression patterns. Significance: We confirm and extend anticancer potential of these antimalarials and we discuss their therapeutic potential based on clinical data.
Anticancer properties of distinct antimalarial drug classes.
Sex, Age, Cell line
View SamplesAnalysis of glucose and Lipid metabolism in male and female offspring after protein restriction of the mother
Sex-dependent programming of glucose and fatty acid metabolism in mouse offspring by maternal protein restriction.
Sex, Specimen part
View SamplesPolymorphonuclear cells (neutrophils) play an important role in the systemic inflammatory response syndrome and the development of sepsis. These cells are essential for the defense against microorganisms, but may also cause tissue damage. Therefore, neutrophil numbers and activity are considered to be tightly regulated. Previous studies have investigated gene transcription during experimental endotoxemia in whole blood and peripheral blood mononuclear cells. However, the gene transcription response of the circulating pool of neutrophils to systemic inflammatory stimulation in vivo is currently unclear. We examined neutrophil gene transcription kinetics in healthy human subjects (n=4) administered a single dose of endotoxin (LPS, 2 ng/kg iv). In addition, freshly isolated neutrophils were stimulated ex vivo with LPS, TNF, G-CSF and GM-CSF to identify stimulus-specific gene transcription responses. Whole transcriptome microarray analysis of circulating neutrophils at 2, 4 and 6 hours after LPS infusion revealed activation of inflammatory networks which are involved in signaling of TNF and IL-1 and IL-1. The transcriptome profile of inflammatory activated neutrophils in vivo reflects extended survival and regulation of inflammatory responses. We show that these changes in neutrophil transcriptome are most likely due to a combination of early activation of circulating neutrophils by TNF and G-CSF and a mobilization of young neutrophils from the bone marrow.
Transcriptome kinetics of circulating neutrophils during human experimental endotoxemia.
Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Drug-induced histone eviction from open chromatin contributes to the chemotherapeutic effects of doxorubicin.
Age, Specimen part, Cell line, Treatment, Time
View SamplesOne major class of anti-cancer drugs targets topoisomerase II to induce DNA double-strand breaks and cell death of fast growing cells. In vitro experiments showed that doxorubicin can induce histone eviction as well as DNA damage, while etoposide can only induce DNA damage. Here, we compare the transcription responses of different tissues to doxorubicin or etoposide treatment in vivo.
Drug-induced histone eviction from open chromatin contributes to the chemotherapeutic effects of doxorubicin.
Age, Specimen part, Treatment, Time
View SamplesBRAF(V600E) mutant melanomas treated with inhibitors of the BRAF and MEK kinases almost invariably develop resistance, which is frequently caused by reactivation of the Mitogen Activated Protein Kinase (MAPK) pathway. To identify novel treatment options for such patients, we searched for acquired vulnerabilities of MAPK inhibitor-resistant melanomas. We find that resistance to BRAF+MEK inhibitors is associated with increased levels of reactive oxygen species (ROS). Subsequent treatment with the histone deacetylase inhibitor (HDACi) vorinostat represses SLC7A11 that leads to a lethal increase in the already elevated levels of ROS in drug-resistant cells, thereby causing selective apoptotic death of only the drug resistant tumor cells. Consistently, treatment of BRAF inhibitor-resistant melanoma with HDACi in mice results in a dramatic tumor regression. In a study in patients with advanced BRAF+MEK inhibitor resistant melanoma, we find that HDACi can selectively ablate drug-resistant tumor cells, providing clinical proof of concept for the novel therapy identified here. Overall design: one replicate of RNA Seq data A375, A375R, A375DR vorinostat treated and patient samples pre- post- vorinostat treatment
An Acquired Vulnerability of Drug-Resistant Melanoma with Therapeutic Potential.
Specimen part, Disease, Disease stage, Cell line, Treatment, Subject
View SamplesIslets are known to respond to changes in ambient glucose. To quantify the transcriptome-wide changes in ambient glucose, we compared transcriptome of islets exposed to low and high glucose. Overall design: Isolated islets from wild type male mice. Islets from adult males were pooled, cultured overnight in RPMI containing 11 mM glucose. The next day, all islets were starved in RPMI containing 2.8 mM glucose for 2 hours before stimulation with 2.8 mM glucose or 16.8 mM glucose for 12 hours. Islets were lysed in Trizol for RNA isolation and library construction.
The transcriptional landscape of mouse beta cells compared to human beta cells reveals notable species differences in long non-coding RNA and protein-coding gene expression.
No sample metadata fields
View SamplesRodent models are widely used to study diabetes. Yet, significant gaps remain in our understanding of mouse islet physiology. We generated comprehensive transcriptomes of mouse delta, beta and alpha cells using two separate triple transgenic mouse models generated for this purpose. This enables systematic comparison across thousands of genes between the three major endocrine cell types of the islets of Langerhans whose principal hormones control nutrient homeostasis. Overall design: FACS purified delta or alpha cells and beta cells from the same islets. Islets were isolated from triple transgenic offspring of a cross between mIns1-H2b-mCherry (Jax # 028589) and either Sst-Cre (delta) or Gcg-cre (alpha) cells and a floxed YFP allele to label delta or alpha cells, respectively. Islets from replicate groups of 10 to 12 triple transgenic animals for each group were pooled by sex to obtain sufficient material. Pooled islets were dissociated, sorted and collect in Trizol for RNA isolation and library construction.
Comprehensive alpha, beta and delta cell transcriptomes reveal that ghrelin selectively activates delta cells and promotes somatostatin release from pancreatic islets.
Sex, Specimen part, Subject
View Samples