title: Induction of prostaglandin endoperoxide synthase-1 (COX-1) in a human promonocytic cell line by treatment with the differentiating agent TPA.
abstract: Prostaglandin endoperoxide synthase (PGH synthase) is responsible for converting arachdonic acid to PGH2, the common precursor of prostaglandins. It has been shown previously that phorbol ester-induced differentiation of human promonocytic leukemia cell lines is accompanied by induction of PGH synthase enzyme and enhanced capacity to produce prostaglandins. However, the identity of the isoform of PGH synthase, i.e., PGH synthase-1 or -2, that is induced under these conditions has not been established. Northern and Western analyses revealed a dramatic increase in levels of PGH synthase-1 mRNA and protein levels within 24 hr after treatment of THP-1 cells with phorbol ester. No significant increase in PGH synthase-2 mRNA or protein was observed. The increases in PGH synthase-1 were accompanied by an enhanced capacity of the cells to produce PGE2. The current findings indicate that expression of PGH synthase-1 is greatly enhanced in a promonocytic cell line by treatment with an agent that induces differentiation.
authors.affiliation: A.B. Hancock, Jr. Memorial Laboratory of Cancer Research, Vanderbilt University School of Medicine, Nashville, TN 37232, USA.
authors.forename: C J
authors.initials: CJ
authors.lastname: Smith
authors.forename: J D
authors.initials: JD
authors.lastname: Morrow
authors.forename: L J
authors.initials: LJ
authors.lastname: Roberts
authors.forename: L J
authors.initials: LJ
authors.lastname: Marnett
mesh_terms: D002118:Calcium / Q000494:pharmacology; D002454:Cell Differentiation / Q000187:drug effects; D051545:Cyclooxygenase 1; D051546:Cyclooxygenase 2; D003907:Dexamethasone / Q000494:pharmacology; D015232:Dinoprostone / Q000096:biosynthesis; D004790:Enzyme Induction; D006801:Humans; D007527:Isoenzymes / Q000096:biosynthesis*; D008274:Magnesium / Q000494:pharmacology; D008565:Membrane Proteins; D009000:Monocytes; D011451:Prostaglandin-Endoperoxide Synthases / Q000096:biosynthesis*; D014176:Protein Biosynthesis; D012333:RNA, Messenger / Q000096:biosynthesis; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology*; D014158:Transcription, Genetic; D014407:Tumor Cells, Cultured
chemical_list: D007527:Isoenzymes; D008565:Membrane Proteins; D012333:RNA, Messenger; D003907:Dexamethasone; D051545:Cyclooxygenase 1; D051546:Cyclooxygenase 2; C496511:PTGS1 protein, human; C496540:PTGS2 protein, human; D011451:Prostaglandin-Endoperoxide Synthases; D008274:Magnesium; D015232:Dinoprostone; D013755:Tetradecanoylphorbol Acetate; D002118:Calcium