Lipoxygenase is a family of non-heme, iron-containing enzymes. Most of these enzymes catalyze the dioxygenation of polyunsaturated fatty acids with cis,cis-1,4-pentadiene structures, synthesizing cell signaling molecules. These signaling molecules play various roles: they act as autocrine signals to regulate their parent cells, paracrine signals to regulate nearby cells, and endocrine signals to regulate distant cells.