Abstract

The increased expression of COX-2 in carcinoma tissue is found in gastric cancer, lung cancer and breast cancer as well as colon cancer. It was shown that COX-2 played an important role in carcinogenesis by an experiment using a cultured cell and an animal experiment using a knockout mouse. The inhibitory effect of COX-2 inhibitor on polyps in familial adenomatous polyposis (FAP) patients was reported from the clinical aspect, and the U. S. Food and Drug Administration (FDA) approved administration of a COX-2 inhibitor to FAP patients. COX-2 plays an important role in proliferation, invasion and metastasis of cancer. COX-2 expression was reportedly enhanced in lung cancer by an anticancer agent and radiotherapy, and clinical application of a COX-2 inhibitor is attempted. In addition, the experimental examination showed the inhibitory effect of a COX-2 inhibitor on hematogenous metastasis of colon cancer. The mechanism of the COX-2 inhibitor remains unclear. Clinical application of the COX-2 inhibitor to an effective anti-tumor agent is expected after more studies have been conducted on its molecular biologic function.