During the metastasis, cyclooxygenase-2 (COX-2), a key enzyme in the conversion of arachidonic acid to prostaglandins and other eicosanoids, played an important role in promoting a more metastatic phenotype in colorectal tumor cells, while COX-2 inhibition in vivo can attenuate the metastatic potential of colorectal tumors in both humans and mice (6, 7). This evidence concerns the gene PTGS2 and colorectal neoplasm.