The human colon cancer cell line, HCA-7 Colony 29 expresses Cox-2. An interesting feature of this cell line is that it forms polarised epithelial sheets which allows examination of the trafficking and release of biomolecules in vitro. Cyclooxygenases (COXs) are key enzymes in the conversion of arachidonic acid to prostaglandins and other eicosanoids. It has been found that colonic polyps and cancers overexpress Cox-2 and that the inhibition of this enzyme by nonsteroidal anti-inflammatory drugs decreases the risk of colonic neoplasia. This cell line is useful for studying the role of Cox-2 in cancer cell biology and the investigation of colorectal epithelial cell polarity. Imperial College Innovations has stated that this cell line is not to be supplied to commercial organisations. (Sigma-Aldrich catalog number 02091238)