Cytoplasmic phospholipase A2 expression in human colon adenocarcinoma is correlated with cyclooxygenase-2 expression and contributes to prostaglandin E2 production

Cytoplasmic phospholipase A2 (cPLA2) has a key role in prostaglandin production. The role of cPLA2 in intestinal tumorigenesis has been suggested, however, contradictory data are found in the literature. We evaluated cPLA2 and cyclooxygenase-2 (COX-2) protein expression in 65 colon carcinomas by immunohistochemistry, and in eight colorectal cancer cell lines by Western Blot. PGE2 production was evaluated by enzyme-immunoassay in the cell lines. We demonstrate that cPLA2 is overexpressed in approximately 50% of colon cancers and cell lines. cPLA2 expression is correlated with COX-2 expression. Both cPLA2 and COX-2 expressions are important in regard to PGE2 production. Our data suggest that cPLA2 might be involved in colon tumor development.