title: Nitric oxide upregulates the cyclooxygenase-2 expression through the cAMP-response element in its promoter in several cancer cell lines.
abstract: We previously showed that nitric oxide (NO) induces overexpression of cyclooxygenase-2 (COX-2) and production of prostaglandin E(2) in cancer cells. Here, we investigated the mechanisms by which NO induces COX-2 expression in cancer cells. We found that the cAMP-response element (CRE) is a critical factor in NO-induced COX-2 expression in all cells tested. We found that in cancer cells, three transcription factors (TFs) - cAMP response element-binding protein (CREB), activating transcription factor-2 (ATF-2) and c-jun, bound the CRE in the COX-2 promoter, and their activities were increased by addition of the NO donor, S-nitroso-N-acetyl-D,L-penicillamine (SNAP). NO-induced activation of soluble guanylate cyclase (sGC), p38 and c-Jun NH(2)-terminal kinase (JNK) upregulated the three TFs, leading to COX-2 overexpression. Addition of dibutyryl-cGMP (db-cGMP) induced COX-2 expression in a manner similar to SNAP; this induction was blocked by a p38 inhibitor (SB202190), but not by a JNK inhibitor (SP600125). NO-induced cGMP was found to activate CREB and ATF-2 in a p38, but not c-jun-dependent manner, while NO induced JNK in a cGMP-independent manner, leading to subsequent activation of c-jun and ATF-2. These results suggest that the low concentrations of endogenous NO present in cancer cell may induce the expression of many genes, including COX-2, which promotes the growth and survival of tumor cells.
authors: Department of Tumor Biology, College of Medicine, Seoul National University, Chongno-gu, Korea.
authors: Seok-Woo
authors: SW
authors: Park
authors: Myung-Whun
authors: MW
authors: Sung
authors: Dae-Seog
authors: DS
authors: Heo
authors: Hiroyasu
authors: H
authors: Inoue
authors: Seon-Hui
authors: SH
authors: Shim
authors: Kwang-Hyun
authors: KH
authors: Kim
mesh_terms: D051698:Activating Transcription Factor 2; D001483:Base Sequence; D045744:Cell Line, Tumor; D017362:Cyclic AMP Response Element-Binding Protein / Q000502:physiology; D006152:Cyclic GMP / Q000502:physiology; D051546:Cyclooxygenase 2; D017931:DNA Primers; D004789:Enzyme Activation; D004791:Enzyme Inhibitors / Q000494:pharmacology; D006801:Humans; D048031:JNK Mitogen-Activated Protein Kinases / Q000378:metabolism; D008565:Membrane Proteins; D009569:Nitric Oxide / Q000502:physiology*; D019001:Nitric Oxide Synthase / Q000037:antagonists & inhibitors; D011401:Promoter Regions, Genetic; D011451:Prostaglandin-Endoperoxide Synthases / Q000235:genetics*; D016755:Proto-Oncogene Proteins c-jun / Q000187:drug effects / Q000502:physiology; D014157:Transcription Factors / Q000187:drug effects / Q000502:physiology*; D015854:Up-Regulation / Q000502:physiology*; D048051:p38 Mitogen-Activated Protein Kinases / Q000378:metabolism
chemical_list: C497105:ATF2 protein, human; D051698:Activating Transcription Factor 2; C115163:CREB1 protein, human; D017362:Cyclic AMP Response Element-Binding Protein; D017931:DNA Primers; D004791:Enzyme Inhibitors; D008565:Membrane Proteins; D016755:Proto-Oncogene Proteins c-jun; D014157:Transcription Factors; D009569:Nitric Oxide; D019001:Nitric Oxide Synthase; D051546:Cyclooxygenase 2; C496540:PTGS2 protein, human; D011451:Prostaglandin-Endoperoxide Synthases; D048031:JNK Mitogen-Activated Protein Kinases; D048051:p38 Mitogen-Activated Protein Kinases; D006152:Cyclic GMP