Epithelial tumor cells (E) underwent EMT in vivo in FVB/N mice generating mesenchymal tumors. Mesenchymal cell lines (M1-M4) were each derived from a different mouse. This study compares gene expression between these two different tumor types.
Immune-induced epithelial to mesenchymal transition in vivo generates breast cancer stem cells.
No sample metadata fields
View SamplesMurine prostate epithelial cells (PECs) were obtained from Ccnd1-/- and Ccnd1+/+ FvB mice (2-3 months of age). RNA extracted from PECs (3 technical replicates for each group) was labeled and used to probe Affymetrix 430_2.0 arrays.
Cyclin D1 Promotes Androgen-Dependent DNA Damage Repair in Prostate Cancer Cells.
No sample metadata fields
View SamplesmiR-155 transgenic mice develop pre-B cell leukemia/lymphoma. Though some targets of miR-155 are known, understanding of the mechanism by which miR-155 overexpression drives malignant transformation is not known. MicroRNAs regulate multiple genes.
miR-155 targets histone deacetylase 4 (HDAC4) and impairs transcriptional activity of B-cell lymphoma 6 (BCL6) in the Eμ-miR-155 transgenic mouse model.
No sample metadata fields
View SamplesThe gastrointestinal (GI) tract can have significant impact on the regulation of the whole body metabolism and may contribute to the development of obesity and diabetes. To systemically elucidate the role of the GI tract in obesity, we performed a transcriptomic analyses in different parts of the GI tract of two obese mouse models: ob/ob and high-fat diet (HFD) fed mice. Compared to their lean controls, both obese mouse groups had significant amount of gene expression changes in the stomach (ob/ob: 959; HFD: 542), much more than the number of changes in the intestine. Despite the difference in genetic background, the two mouse models shared 296 similar gene expression changes in the stomach. Among those genes, some had known associations to obesity, diabetes and insulin resistance. In addition, the gene expression profile strongly suggested an increased gastric acid secretion in both obese mouse models, probably through an activation of the gastrin pathway. In conclusion, our data reveal a previously unknown dominant connection between the stomach and obesity.
Significant obesity-associated gene expression changes occur in the stomach but not intestines in obese mice.
Specimen part
View SamplesAnalysis of the transcriptional profiles of mRNA and microRNA in Rasless fibroblasts. 4-Hydroxy-tamoxifen (4-OHT) treatment triggers removal of K-Ras expression in [H-Ras-/-;N-Ras-/-;K-Raslox/lox;RERTert/ert ] mouse fibroblasts (named K-Raslox) generating Rasless MEFs which are unable to proliferate, but recover proliferative ability after ectopic expression of constitutively active downstream kinases such as BRAF and MEK1.
Reversible, interrelated mRNA and miRNA expression patterns in the transcriptome of Rasless fibroblasts: functional and mechanistic implications.
Specimen part, Cell line, Treatment
View SamplesBACKGROUND: p53 is an important tumor suppressor with a known role in the later stages of colorectal cancer, but its relevance to the early stages of neoplastic initiation remains somewhat unclear. Although p53-dependent regulation of Wnt signalling activity is known to occur, the importance of these regulatory mechanisms during the early stages of intestinal neoplasia has not been demonstrated.
A limited role for p53 in modulating the immediate phenotype of Apc loss in the intestine.
Specimen part
View SamplesThe gastrointestinal tract of mammals is inhabited by hundreds of distinct species of commensal microorganisms that exist in a mutualistic relationship with the host. The process by which the commensal microbiota influence the host immune system is poorly understood. We show here that colonization of the small intestine of mice with a single commensal microbe, segmented filamentous bacterium (SFB), is sufficient to induce the appearance of CD4+ T helper cells that produce IL-17 and IL-22 (Th17 cells) in the lamina propria. SFB adhere tightly to the surface of epithelial cells in the terminal ileum of mice with Th17 cells but are absent from mice that have few Th17 cells. Colonization with SFB was correlated with increased expression of genes associated with inflammation, anti-microbial defenses, and tissue repair, and resulted in enhanced resistance to the intestinal pathogen Citrobacter rodentium. Control of Th17 cell differentiation by SFB may thus establish a balance between optimal host defense preparedness and potentially damaging T cell responses. Manipulation of this commensal-regulated pathway may provide new opportunities for enhancing mucosal immunity and treating autoimmune disease.
Induction of intestinal Th17 cells by segmented filamentous bacteria.
Specimen part
View SamplesThe specific ablation of Rb1 gene in stratified epithelia (RbF/F;K14cre) promotes proliferation and altered differentiation but is insufficient to produce spontaneous tumors. The pRb relative, p107, compensates some of the functions of pRb in these tissues, however RbF/F;K14cre;p107-/- mice die postnatally. Acute pRb loss in stratified epithelia, using an inducible mouse model (RbF/F;K14creERTM), shows that p107 exerts specific tumor suppressor functions in its absence. After simultaneous absence of pRb and p107, p53 transcriptional function is impaired and Pten expression is reduced. All mutant mice develop spontaneous squamous tumors carcinomas rapidly. Gene expression analysis of mouse tumors, besides supporting the impaired p53 function and the susceptibility to Akt/mTOR inhibitors, also revealed significant overlap with human squamous carcinomas. Thus, RbF/F;K14creERTM;p107-/- may constitute a new mouse model for these malignancies. Collectively, these data demonstrate the existence of a previously unreported functional connection between pRb, Pten and p53 tumor suppressors, through p107, of a particular relevance in squamous tumor development.
A novel tumor suppressor network in squamous malignancies.
Specimen part
View SamplesDysregulated Wnt signalling is seen in approximately 30% of hepatocellular cancers, thus finding pathways downstream of activation of Wnt signalling is key. Using cre lox technology we have deleted the the adenomatous polyposis coli tumour suppressor protein (Apc) within the adult mouse liver and observed a rapid increase in nuclear beta-catenin and C-Myc. This is associated with an induction of proliferation leading to hepatomegally within 4 days of gene deletion. To investigate the downstream pathways responsible for these phenotypes we analysed the impact of inactivating Apc in the context of deficiency of the potentially key effectors beta-catenin and c-Myc. beta-catenin loss rescues both the proliferation and hepatomegally phenotypes following Apc loss. However c-Myc deletion, which rescues the phenotypes of Apc loss in the intestine, had no effect on the phenotypes of Apc loss. The consequences of deregulation the Wnt pathway within the liver are therefore strikingly different to those observed within the intestine, with the vast majority of Wnt targets beta-catenin dependent but c-Myc independent in the liver.
B-catenin deficiency, but not Myc deletion, suppresses the immediate phenotypes of APC loss in the liver.
No sample metadata fields
View SamplesA permantly active form of the oncogene Akt was expressed in the keratinocytes of the basal proliferative layer of the epidermis. Stem cells of the hair follicle expressing the cell surface marker CD34 were isolated. RNA form the CD34(+) and CD34(-) keratinocytes was extracted and and hybridized to Mouse Genome 430 2.0 Affymetrix arrays.
Akt signaling leads to stem cell activation and promotes tumor development in epidermis.
Specimen part
View Samples