BioProject

Inflammatory bowel diseases (IBD) in humans are characterized by chronic inflammation and gastrointestinal tissue damage, caused by a combination of genetic and environmental factors. More...

Inflammatory bowel diseases (IBD) in humans are characterized by chronic inflammation and gastrointestinal tissue damage, caused by a combination of genetic and environmental factors. It has been largely documented that IBD frequently lead to colorectal cancers (CRC). The identification of causative factors of IBD is thus essential to understand CRC progression and develop therapeutical approaches. Models have been described in which molecular alterations are combined with inflammatory treatments in order to recapitulate IBD-associated CRC. Here, we describe a mouse line, α6fl/fl Villin-Cre, in which inactivation of the gene encoding the integrin alpha-6 subunit (ITGA6) specifically in the intestinal mucosa results into chronic inflammation and intestinal carcinogenesis. In these mice, the loss of integrin alpha-6 beta-4, a receptor mediating the attachment of epithelial cells to laminins, leads to epithelial detachment, hyperplasia, chronic inflammation, rectal prolapses, and ultimately adenocarcinomas. Alterations of differentiation affecting mucus secreting (goblet) cells as well as changes in expression of essential intestinal transcription factors were detected. Thus alpha-6 beta-4 integrin is a key factor for the maintenance of intestinal integrity and its loss may represent a risk factor for tumor progression associated with IBD. Overall design: Transcriptome analysis of RNA from normal versus inflamed and carcinomatous rectal mucosa of α6 integrin deficient intestinal epithelium mice was performed. RNAs were prepared from 5 adenocarcinomas, which were macrodissected from the rectal prolapses and 4 flanking inflamed rectal mucosa of 53-80 week-old α6fl/fl Villin-Cre mice. RNAs from normal rectal mucosa were obtained by rectum scraping from 4 matched control animals. The transcriptome analysis was performed using the Affymetrix Mouse Gene 1.0 ST arrays. Images were processed using affymetrix GeneChip® Command Console® Software (AGCC) (version 2.0) and numerical value were generated using Affymetrix Expression Console™ Software (version 1.1). Less...