Finally, we examined the expression of the EP4 prostaglandin-receptor (EP4R), a receptor that has been implicated in the pathogenesis of IBD and is a target of anti-inflammatory and analgesic drugs including nonsteroidal anti-inflammatory drugs (NSAIDS), COX-2 inhibitors, and the piprant class, which are selective EP4R inhibitors. This evidence concerns the gene PTGER4 and inflammatory bowel disease.