Effects of dexamethasone on gene expression in rat pancreatic AR42J cell line

The rat pancreatic cell line AR42J is relatively undifferentiated under normal culture conditions. When the glucocorticoid dexamethasone is added to the medium the cells display a dramatic decrease in proliferative rate and are induced to a more exocrine phenotype that includes increased expression of exocrine pancreas products (digestive enzymes) and more developed regulated secretion. We used microarray to determine changes in gene expression comparing control (without dexamethasone) vs induced (plus dexamethasone). Three independent pairs of control and dexamethasone-induced cultures were prepared followed by total RNA extraction and microarray analysis using the Affymetrix Rat 230A chip.