PTGS2 and colonic neoplasm: Numerous studies have shown that the expression of COX-2, one of the two isoforms of COX, is increased significantly in colonic neoplasms compared with normal colonic mucosa, and that COX-2 plays an integral role in colon cancer tumorigenesis and proliferation (Sheng et al, 1997; Barnes et al, 1998; Barnes and Lee, 1998; Sawaoka et al, 1998; Tsujii et al, 1998).