title: Cyclooxygenase-2 expression by transcription factors in Helicobacter pylori-infected gastric epithelial cells: comparison between HP 99 and NCTC 11637.
abstract: Helicobacter pylori, a gram-negative spiral bacterium, has been associated with chronic gastritis and gastric cancer. HP 99, isolated from the Korean patients, and NCTC 11637, obtained from ATCC, have different genotypes. The present study aims to investigate whether these H. pylori strains show the discrepancy for activating transcription factors (NF-kappaB, AP-1, C/EBP) and induction of cyclooxygenase-2 (COX-2) gene in gastric epithelial AGS cells. After treatment of H. pylori to AGS cells at the ratio of 300:1, the activation of transcription factors was assessed by electrophoretic mobility shift assay. COX-2 protein was determined by Western blot analysis. The level of 6-keto-prostaglandin F(1alpha) (6-keto-PGF(1alpha)), a COX-2 product, was measured in the medium by enzyme-linked immunosorbent assay. As a result, both H. pylori strains similarly induced COX-2 expression via activation of NF-kappaB, not C/EBP, and increased the level of 6-keto-PGF(1alpha). HP 99 showed much higher activation of AP-1 compared to NCTC 11637. NF-kappaB might play an important role in COX-2 expression in H. pylori-induced gastric inflammation as compared to other transcription factors.
authors.affiliation: Department of Pharmacology and Institute of Gastroenterology, Brain Korea 21 Project for Medical Science, Yonsei University College of Medicine, Seoul 120-752, Korea.
authors.forename: Ji Hye
authors.initials: JH
authors.lastname: Seo
authors.forename: Hyeyoung
authors.initials: H
authors.lastname: Kim
authors.forename: Kyung Hwan
authors.initials: KH
authors.lastname: Kim
mesh_terms: D000230:Adenocarcinoma; D051546:Cyclooxygenase 2; D005753:Gastric Mucosa / Q000201:enzymology* / Q000382:microbiology*; D015971:Gene Expression Regulation, Enzymologic / Q000502:physiology*; D015972:Gene Expression Regulation, Neoplastic; D005838:Genotype; D016481:Helicobacter Infections / Q000201:enzymology / Q000235:genetics*; D016480:Helicobacter pylori / Q000145:classification / Q000235:genetics / Q000472:pathogenicity*; D006801:Humans; D007527:Isoenzymes / Q000235:genetics*; D007723:Korea; D008565:Membrane Proteins; D011451:Prostaglandin-Endoperoxide Synthases / Q000235:genetics*; D013274:Stomach Neoplasms; D014157:Transcription Factors / Q000378:metabolism*; D014407:Tumor Cells, Cultured
chemical_list: D007527:Isoenzymes; D008565:Membrane Proteins; D014157:Transcription Factors; D051546:Cyclooxygenase 2; C496540:PTGS2 protein, human; D011451:Prostaglandin-Endoperoxide Synthases