title: Up-regulation of cyclooxygenase-1 in neuroblastoma cell lines by retinoic acid and corticosteroids.
abstract: Cyclooxygenases-1 and -2 are both expressed in neuronal cells in vivo. In the neuroblastoma cell lines NG108 and N2a, however, only cyclooxygenase-1 was detectable. Differentiation of the cells with retinoic acid increased cyclooxygenase-1 mRNA and protein expression within 24 and 48 h, respectively. A further increase was observed when the cells were concomitantly treated with the glucocorticoid dexamethasone (a 2-3-fold increase compared with retinoic acid alone). In the absence of retinoic acid, dexamethasone only slightly up-regulated cyclooxygenase-1 expression. The inhibitor of protein synthesis cycloheximide abrogated the effect of dexamethasone, indicating the involvement of newly synthesised proteins. Retinoic acid increased the transcription of cyclooxygenase-1 mRNA, determined with a luciferase-coupled promoter construct. Dexamethasone only slightly augmented cyclooxygenase-1-promoter activity but increased cyclooxygenase-1 mRNA stability. Other corticosteroids, hydrocortisone and aldosterone, also up-regulated cyclooxygenase-1 whereas neurosteroids or oestrogen were ineffective. Up-regulation was mediated primarily by the glucocorticoid receptor, because the receptor antagonist RU486 strongly reduced the effects of all corticosteroids. This indicated that in NG108 cells, the mineralocorticoid aldosterone may bind to the glucocorticoid receptor. Treatment of NG108 or N2a cells with corticosteroids did not alter the morphological phenotype obtained during differentiation. We thus show that corticosteroids, which down-regulate cyclooxygenase expression in most cell types, up-regulate cyclooxygenase-1 during neuronal differentiation.
authors: Medizinische Klinik IV, Universität Erlangen-Nürnberg, Erlangen, Germany Kompetenzzentrum Umweltmedizin, Rupprecht-Karls-Universität Heidelberg, Mannheim, Germany.
authors: N
authors: N
authors: Schneider
authors: S
authors: S
authors: Lanz
authors: R
authors: R
authors: Ramer
authors: D
authors: D
authors: Schaefer
authors: M
authors: M
authors: Goppelt-Struebe
mesh_terms: D000305:Adrenal Cortex Hormones / Q000494:pharmacology*; D000450:Aldosterone / Q000494:pharmacology; D000818:Animals; D001562:Benzimidazoles / Q000494:pharmacology; D003994:Bucladesine / Q000494:pharmacology; D000001:Calcimycin / Q000494:pharmacology; D002454:Cell Differentiation / Q000187:drug effects; D003513:Cycloheximide / Q000494:pharmacology; D051545:Cyclooxygenase 1; D051546:Cyclooxygenase 2; D003687:Dehydroepiandrosterone / Q000494:pharmacology; D019314:Dehydroepiandrosterone Sulfate / Q000494:pharmacology; D003907:Dexamethasone / Q000494:pharmacology; D015232:Dinoprostone / Q000096:biosynthesis; D004357:Drug Synergism; D004790:Enzyme Induction / Q000187:drug effects; D004958:Estradiol / Q000494:pharmacology; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects; D017930:Genes, Reporter; D005910:Glioma / Q000201:enzymology / Q000473:pathology; D006822:Hybrid Cells / Q000187:drug effects / Q000201:enzymology; D006854:Hydrocortisone / Q000494:pharmacology; D007476:Ionophores / Q000494:pharmacology; D007527:Isoenzymes / Q000096:biosynthesis* / Q000235:genetics; D008156:Luciferases / Q000096:biosynthesis / Q000235:genetics; D008565:Membrane Proteins; D051379:Mice; D015735:Mifepristone / Q000494:pharmacology; D009363:Neoplasm Proteins / Q000096:biosynthesis* / Q000235:genetics; D009419:Nerve Tissue Proteins / Q000096:biosynthesis* / Q000235:genetics; D009447:Neuroblastoma / Q000201:enzymology* / Q000473:pathology; D011401:Promoter Regions, Genetic; D011451:Prostaglandin-Endoperoxide Synthases / Q000096:biosynthesis* / Q000235:genetics; D011500:Protein Synthesis Inhibitors / Q000494:pharmacology; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics; D012334:RNA, Neoplasm / Q000096:biosynthesis / Q000235:genetics; D011965:Receptors, Glucocorticoid / Q000187:drug effects / Q000502:physiology; D011993:Recombinant Fusion Proteins / Q000096:biosynthesis; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D014162:Transfection; D014212:Tretinoin / Q000494:pharmacology*; D014407:Tumor Cells, Cultured / Q000187:drug effects / Q000201:enzymology
chemical_list: C110962:5,6-dichlorobenzimidazole; D000305:Adrenal Cortex Hormones; D001562:Benzimidazoles; D007476:Ionophores; D007527:Isoenzymes; D008565:Membrane Proteins; D009363:Neoplasm Proteins; D009419:Nerve Tissue Proteins; D011500:Protein Synthesis Inhibitors; D012333:RNA, Messenger; D012334:RNA, Neoplasm; D011965:Receptors, Glucocorticoid; D011993:Recombinant Fusion Proteins; D015735:Mifepristone; D000001:Calcimycin; D003687:Dehydroepiandrosterone; D000450:Aldosterone; D004958:Estradiol; D014212:Tretinoin; D019314:Dehydroepiandrosterone Sulfate; D003994:Bucladesine; D003907:Dexamethasone; D003513:Cycloheximide; D008156:Luciferases; D051545:Cyclooxygenase 1; D051546:Cyclooxygenase 2; D011451:Prostaglandin-Endoperoxide Synthases; C496512:Ptgs1 protein, mouse; D015232:Dinoprostone; D013755:Tetradecanoylphorbol Acetate; D006854:Hydrocortisone