Research in my laboratory is focused on the exploration of steroid hormone and cytokine driven effects on the elements of arachidonic acid metabolism in cultured osteoblast-like cells and in breast and breast cancer cells. The effects of estrogen in particular have been of interest in each model system. Estrogen mediates the receptor-dependent release of arachidonic acid from cellular phospholipid stores, and its conversion into bioactive signaling molecules, including the prostaglandins, in the osteblast-like cells. In breast cancer cells, estrogen appears to alter the expression of the enzymes (phospholipases) that are chiefly responsible for the release of the fatty acid. The consequences of the estrogen-driven effects on cancer cell arachidonic acid metabolism may extend into the production various signaling molecules, and into the mediation of such cellular proceeses as replication and apoptosis.