The Wnt signaling pathway is deregulated in over 90% of human colorectal cancers. Catenin, the central signal transducer of the Wnt pathway, can directly modulate gene expression by interacting with transcription factors of the TCF/LEF-family. In the present study we investigate the role of Wnt signaling in the homeostasis of intestinal epithelium using tissue-specific, inducible beta-catenin gene ablation in adult mice. Block of Wnt/beta-catenin signaling resulted in rapid loss of transient-amplifying cells and crypt structures. Importantly, intestinal stem cells were induced to terminally differentiate upon deletion of beta-catenin resulting in a complete block of intestinal homeostasis and fatal loss of intestinal function. Transcriptional profiling of mutant crypt mRNA isolated by laser capture micro dissection confirmed those observations and allowed to identify genes potentially responsible for the functional preservation of intestinal stem cells.
Wnt/beta-catenin is essential for intestinal homeostasis and maintenance of intestinal stem cells.
No sample metadata fields
View SamplesRecent studies suggest that thousands of genes may contribute to breast cancer pathophysiologies when deregulated by genomic or epigenomic events. Here, we describe a model system to appraise the functional contributions of these genes to breast cancer subsets. In general, the recurrent genomic and transcriptional characteristics of 51 breast cancer cell lines mirror those of 145 primary breast tumors, although some significant differences are documented. The cell lines that comprise the system also exhibit the substantial genomic, transcriptional, and biological heterogeneity found in primary tumors. We show, using Trastuzumab (Herceptin) monotherapy as an example, that the system can be used to identify molecular features that predict or indicate response to targeted therapies or other physiological perturbations.
A collection of breast cancer cell lines for the study of functionally distinct cancer subtypes.
Cell line
View SamplesBased on the findings of increased IEL in duodenal biopsies in CVID, an overlap with celiac disease has been suggested. In the present study, increased IEL, in particular in the pars descendens of the duodenum, was one of the most frequent histopathological finding. We therefore examined the gene expression profile in pars descendens of duodenum in CVID patients with increased IEL (n=12, IEL mean 34 [range 22-56] IEL/100 EC), CVID with normal levels of IEL (n=8), celiac disease (n=10, Marsh grade 3a or above) and healthy controls (n=17) by gene expression microarray
A Cross-Sectional Study of the Prevalence of Gastrointestinal Symptoms and Pathology in Patients With Common Variable Immunodeficiency.
Specimen part, Disease, Disease stage
View Samples