This is one of two genes encoding similar enzymes that catalyze the conversion of arachinodate to prostaglandin. The encoded protein regulates angiogenesis in endothelial cells, and is inhibited by nonsteroidal anti-inflammatory drugs such as aspirin. Based on its ability to function as both a cyclooxygenase and as a peroxidase, the encoded protein has been identified as a moonlighting protein. The protein may promote cell proliferation during tumor progression. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Jan 2014],catalytic activity:Arachidonate + AH(2) + 2 O(2) = prostaglandin H(2) + A + H(2)O.,cofactor:Binds 1 heme B (iron-protoporphyrin IX) group per subunit.,function:May play an important role in regulating or promoting cell proliferation in some normal and neoplastically transformed cells.,miscellaneous:This enzyme acts both as a dioxygenase and as a peroxidase.,miscellaneous:This enzyme is the target of nonsteroidal anti-inflammatory drugs such as aspirin.,pathway:Lipid metabolism, prostaglandin biosynthesis.,similarity:Belongs to the prostaglandin G/H synthase family.,similarity:Contains 1 EGF-like domain.,subunit:Homodimer.,
