The cyclooxygenase (COX)-2 gene encodes an inducible prostaglandin synthase enzyme
that is overexpressed in adenocarcinomas and other tumors. Deletion of the murine Cox-2
gene inMin mice reduced the incidence of intestinal tumors, suggesting that it is required for
tumorigenesis. However, it is not known if overexpression of Cox-2 is sufficient to induce
tumorigenic transformation. We have derived transgenic mice that overexpress the human
COX-2 gene in the mammary glands using the murine mammary tumor virus promoter. The …