Global colorectal cancer gene expression in rats

The rat models of colorectal cancer (CRC), such as the azoxymethane (AOM) cancer-inducing model, are important tools for researching cancer initiation pathways. However, there is limited understanding of the expression pathways of underlying normal rat colonic epithelium and how this relates to human colonic epithelium. The aim of this study was to study the acute effects of AOM on the gene and pathway expression of the rat's colonic epithelium, whilst contrasting the background normal global expression patterns along the length of the rat as compared to the normal human colonic epithelium. The study used microarrays to investigate global gene expression of the colonic epithelium from proximal and distal sections of AOM- and saline (normal)-treated Sprague Dawley rats. Rat gene and pathway expression patterns were then compared in-silico with human microarray data (see GSE9254 for files) from normal tissue samples originating from proximal and distal regions of the colon.