PTGS2 and Parkinson disease: Initial studies have shown that COX-2 is an inducible enzyme in cases of inflammation, but more recent studies have also shown that it is expressed in organs such as the kidney and brain.8,9 In addition, the overexpression of COX-2 has been reported in neurodegenerative disorders like Parkinson’s disease, in chronic inflammatory diseases like rheumatoid arthritis, and in various cancers.26