Colorectal cancer is treated with antibodies blocking epidermal growth factor receptor (EGF-R) but therapeutic success is limited. EGF-R is stimulated by soluble ligands, which are derived from transmembrane precursors by ADAM17-mediated proteolytic cleavage. In mouse intestinal cancer models in the absence of ADAM17, tumorigenesis was almost completely inhibited and the few remaining tumors were of low grade dysplasia. RNA-Seq analysis demonstrated downregulation of STAT3 and Wnt pathway components. Since EGF-R on myeloid cells, but not on intestinal epithelial cells is required for intestinal cancer and IL-6 is induced via EGF-R stimulation, we analyzed the role of IL-6 signaling. Tumor formation was equally inhibited in IL-6 -/- and sgp130Fc transgenic mice, in which only trans-signaling via soluble IL-6R is abrogated. ADAM17 is needed for EGF-R-mediated induction of IL-6 synthesis, which via IL-6 trans-signaling induces ß-catenin dependent tumorigenesis. Our data reveal the possibility of a novel strategy for treatment of colorectal cancer, which could circumvent intrinsic and acquired resistance to EGF-R blockade. Overall design: RNA sequencing of tumor tissue and surrounding unaffected tissue of Apc Min/+ and Apc Min/+ ::ADAM17 ex/ex
ADAM17 is required for EGF-R-induced intestinal tumors via IL-6 trans-signaling.
Specimen part, Cell line, Subject
View SamplesPrimordial germ cells (PGCs), the embryonic precursors of eggs and sperm, are a unique model for identifying and studying regulatory mechanisms in singly migrating cells. From their time of specification to eventual colonization of the gonad, mouse PGCs traverse through and interact with many different cell types, including epithelial cells and mesenchymal tissues. Work in drosophila and zebrafish have identified many genes and signaling pathways involved in PGC migration, but little is known about this process in mammals.
Discrete somatic niches coordinate proliferation and migration of primordial germ cells via Wnt signaling.
Specimen part
View SamplesThe vascular endothelial growth factor A (VEGF) is involved in various physiological processes such as angiogenesis or wound healing but is also crucial in pathological events such as tumor growth. Thus, clinical anti-VEGF treatments have been developed which could already prove to have enormous beneficial effects for cancer patients. In this article we describe the first VEGF-derived CD8+ T-cell epitope. The natural HLA ligand SRFGGAVVR was identified by differential mass spectrometry in two primary renal cell carcinomas (RCC) and was significantly over-presented on both tumor tissues. SRFGGAVVR is derived from a cryptic translated region of VEGF presumably by initiation of translation at the non-classical start codon CUG499. SRFGGAVVR specific T-cells were generated in vitro using peptide loaded dendritic cells or artificial antigen presenting cells. They were identified by HLA tetramer analysis after in vitro stimulation. SRFGGAVVR specific CD8+ T-cells were fully functional T-effector cells, which were able to secrete IFN-gamma upon stimulation and killed tumor cells in vitro. Additionally, we have quantitatively analyzed VEGF mRNA and protein levels in RCC tumor and normal tissue samples by gene chip analysis, qRT-PCR, in situ hybridization, and bead based immuno assay. In the future, T-cells directed against VEGF as a tumor associated antigen may represent a possible way of combining peptide-based anti-VEGF immunotherapy with already existent anti-VEGF cancer therapies.
A cryptic vascular endothelial growth factor T-cell epitope: identification and characterization by mass spectrometry and T-cell assays.
No sample metadata fields
View SamplesMounting evidence points to a link between a cancer possessing stem-like properties and a worse prognosis. To understand the biology, a common approach is to integrate network biology with signal processing mechanics. That said, even with the right tools, predicting the risk for a highly susceptible target using only a handful of gene signatures remains very difficult. By compiling the expression profiles of a panel of tumor stem-like cells (TSLCs) originating in different tissues, comparing these to their parental tumor cells (PTCs) and the human embryonic stem cells (hESCs), and integrating network analysis with signaling mechanics, we propose that network topologically-weighted signaling processing measurements under tissue-specific conditions can provide scalable and predicable target identification.
Network biology of tumor stem-like cells identified a regulatory role of CBX5 in lung cancer.
Specimen part
View SamplesPostnatal handling in rodents leads to decreased anxiety-like behavior in adulthood. We used microarrays to look at gene expression differences in the CA1 region of the hippocampus in female mice subjected to postnatal handling compared to controls.
Variation in the large-scale organization of gene expression levels in the hippocampus relates to stable epigenetic variability in behavior.
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View SamplesGenetically identical inbred mice exhibit substantial stable individual variability in exploratory behavior. We used microarrays to look at gene expression differences in the hippocampus in female mice separated by stable differences in exploratory behavior
Variation in the large-scale organization of gene expression levels in the hippocampus relates to stable epigenetic variability in behavior.
No sample metadata fields
View SamplesCD24 is a potential oncogene reported to be overexpressed in a large variety of human malignancies. We have shown that CD24 is overexpressed in 90% of colorectal tumors at a fairly early stage in the multistep process of carcinogenesis. Anti-CD24 monoclonal antibodies (mAb) induce a significant growth inhibition in colorectal and pancreatic cancer cell lines that express the protein. This study is designed to investigate further the effects of CD24 down-regulation using mAb or small interfering RNA in vitro and in vivo. Western blot analysis showed that anti-CD24 mAb induced CD24 protein down-regulation through lysosomal degradation. mAb augmented growth inhibition in combination with five classic chemotherapies. Xenograft models in vivo showed that tumor growth was significantly reduced in mAb-treated mice. Similarly, stable growth inhibition of cancer cell lines was achieved by down-regulation of CD24 expression using short hairpin RNA (shRNA). The produced clones proliferated more slowly, reached lower saturation densities, and showed impaired motility. Most importantly, down-regulation of CD24 retarded tumorigenicity of human cancer cell lines in nude mice. Microarray analysis revealed a similar pattern of gene expression alterations when cells were subjected to anti-CD24 mAb or shRNA. Genes in the Ras pathway, mitogenactivated protein kinase, or BCL-2 family and others of oncogenic association were frequently down-regulated. As a putative new oncogene that is overexpressed in gastrointestinal malignancies early in the carcinogenesis process, CD24 is a potential target for early intervention in the prevention and treatment of cancer.
Targeting CD24 for treatment of colorectal and pancreatic cancer by monoclonal antibodies or small interfering RNA.
Specimen part, Cell line
View SamplesAsthma is a heterogeneous disease. Exercise-induced bronchoconstriction (EIB) is a distinct syndrome that occurs in 30-50% of asthmatics and is characterized by high levels of pro-inflammatory eicosanoids. We identified genes differentially expressed in the airways of asthmatics with EIB relative to asthmatics without EIB. Genes related to epithelial repair and mast cell infiltration including beta-tryptase and carboxypeptidase A3 were upregulated by exercise challenge in the asthma group with EIB. We confirmed that two novel mediators trefoil factor 3 (TFF3) and transglutaminase 2 (TGM2) have increased expression in airways cells and secreted product in the airways. In vitro studies indicate that 1) TFF3 induces nitric oxide synthase in airway epithelial cells from asthmatics and 2) TGM2 augments the enzymatic activity of secreted phospholipase A2 (sPLA2) group X, an enzyme recently been implicated in asthma pathogenesis. Since PLA2 serves as the first rate-limiting step leading to eicosanoid generation, these results suggest that TGM2 may be a key initiator of the airway inflammatory cascade in asthma.
Transglutaminase 2, a novel regulator of eicosanoid production in asthma revealed by genome-wide expression profiling of distinct asthma phenotypes.
No sample metadata fields
View SamplesMyocardial infarction (MI) leads to activation of cardiac fibroblasts (aCFs) and at the same time induces the formation of epicardium-derived cells at the heart surface. To discriminate between the two cell populations, we elaborated a fast and efficient protocol for the simultaneous isolation and characterization of aCFs and epicardial stromal cells (EpiSCs) from the infarcted mouse heart. For the isolation of aCFs and EpiSCs, infarcted hearts (50 min ischaemia/reperfusion) were digested by perfusion with a collagenase-containing medium for only 8 min, while EpiSCs were enzymatically removed from the outside by applying mild shear forces via a motor driven device.
Novel technique for the simultaneous isolation of cardiac fibroblasts and epicardial stromal cells from the infarcted murine heart.
Specimen part
View SamplesAssessment of mRNA expression changes in the B-lymphoblastoid cell line Awells after 6 h and 24 h of starvation-induced autophagy
Autophagy promotes MHC class II presentation of peptides from intracellular source proteins.
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