title: Helicobacter pylori infection triggers aberrant expression of activation-induced cytidine deaminase in gastric epithelium.
abstract: Infection with Helicobacter pylori (H. pylori) is a risk factor for the development of gastric cancer. Here we show that infection of gastric epithelial cells with 'cag' pathogenicity island (cagPAI)-positive H. pylori induced aberrant expression of activation-induced cytidine deaminase (AID), a member of the cytidine-deaminase family that acts as a DNA- and RNA-editing enzyme, via the IkappaB kinase-dependent nuclear factor-kappaB activation pathway. H. pylori-mediated upregulation of AID resulted in the accumulation of nucleotide alterations in the TP53 tumor suppressor gene in gastric cells in vitro. Our findings provide evidence that aberrant AID expression caused by H. pylori infection might be a mechanism of mutation accumulation in the gastric mucosa during H. pylori-associated gastric carcinogenesis.
authors.affiliation: Department of Gastroenterology and Hepatology, Graduate School of Medicine, Kyoto University, 54 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto 606-8507, Japan.
authors.forename: Yuko
authors.initials: Y
authors.lastname: Matsumoto
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Marusawa
authors.forename: Kazuo
authors.initials: K
authors.lastname: Kinoshita
authors.forename: Yoko
authors.initials: Y
authors.lastname: Endo
authors.forename: Tadayuki
authors.initials: T
authors.lastname: Kou
authors.forename: Toshiyuki
authors.initials: T
authors.lastname: Morisawa
authors.forename: Takeshi
authors.initials: T
authors.lastname: Azuma
authors.forename: Il-Mi
authors.initials: IM
authors.lastname: Okazaki
authors.forename: Tasuku
authors.initials: T
authors.lastname: Honjo
authors.forename: Tsutomu
authors.initials: T
authors.lastname: Chiba
mesh_terms: D000942:Antigens, Bacterial / Q000378:metabolism; D001426:Bacterial Proteins / Q000378:metabolism; D003564:Cytidine Deaminase / Q000378:metabolism*; D017931:DNA Primers; D005753:Gastric Mucosa / Q000378:metabolism*; D015972:Gene Expression Regulation, Neoplastic; D016158:Genes, p53 / Q000235:genetics*; D016481:Helicobacter Infections / Q000235:genetics* / Q000378:metabolism; D006801:Humans; D007150:Immunohistochemistry; D008954:Models, Biological; D016296:Mutagenesis / Q000235:genetics; D016328:NF-kappa B / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015398:Signal Transduction / Q000502:physiology; D013274:Stomach Neoplasms / Q000235:genetics* / Q000382:microbiology; D000098830:AICDA (Activation-Induced Cytidine Deaminase)
chemical_list: D000942:Antigens, Bacterial; D001426:Bacterial Proteins; D017931:DNA Primers; D016328:NF-kappa B; C080866:cagA protein, Helicobacter pylori; D000098830:AICDA (Activation-Induced Cytidine Deaminase); D003564:Cytidine Deaminase