title: Effects of Helicobacter pylori γ-glutamyltranspeptidase on apoptosis and inflammation in human biliary cells.
abstract: BACKGROUND
  Several studies have reported the presence of H. pylori in individuals with hepatobiliary diseases, but in vitro and in vivo studies are still needed. Here, we determined the effects of H. pylori γ-glutamyltranspeptidase (GGT) on the induction of apoptosis and IL-8 production in a human cholangiocarcinoma cell line (KKU-100 cells).
  
  
  METHODS
  Cell viability and DNA synthesis were examined by MTT and BrdU assays, respectively. RT-PCR and western blot analysis were performed to assess gene and protein expression, respectively. IL-8 secretion in KKU-100 cells was measured by ELISA.
  
  
  RESULTS
  Exposure to the H. pylori ggt                   (+) strain decreased KKU-100 cell survival and DNA synthesis when compared with cells exposed to the H. pylori                   ggt mutant strain. Treatment with recombinant H. pylori GGT (rHP-GGT) dramatically decreased cell survival and DNA synthesis, and stimulated apoptosis; these features corresponded to an increased level of iNOS gene expression in KKU-100 cells treated with rHP-GGT. RT-PCR and western blot analyses revealed that rHP-GGT treatment enhanced the expression of pro-apoptotic molecules (Bax, Caspase-9, and Caspase-3) and down-regulated the expression of anti-apoptotic molecules (Bcl-2 and Bcl-xL). The extrinsic-mediated apoptosis molecules, including Fas and activated Caspase-8, were not expressed after treatment with rHP-GGT. Furthermore, rHP-GGT significantly stimulated IL-8 secretion in KKU-100 cells.
  
  
  CONCLUSIONS
  Our data indicate that H. pylori GGT might be involved in the development of cancer in hepatobiliary cells by altering cell kinetics and promoting inflammation.
authors.affiliation: Department of Microbiology, Faculty of Medicine, Khon Kaen University, Khon Kaen 40002, Thailand.
authors.forename: Wongwarut
authors.initials: W
authors.lastname: Boonyanugomol
authors.forename: Chariya
authors.initials: C
authors.lastname: Chomvarin
authors.forename: Jea-Young
authors.initials: JY
authors.lastname: Song
authors.forename: Kyung-Mi
authors.initials: KM
authors.lastname: Kim
authors.forename: Jung-Min
authors.initials: JM
authors.lastname: Kim
authors.forename: Myung-Je
authors.initials: MJ
authors.lastname: Cho
authors.forename: Woo-Kon
authors.initials: WK
authors.lastname: Lee
authors.forename: Hyung-Lyun
authors.initials: HL
authors.lastname: Kang
authors.forename: Kwang-Ho
authors.initials: KH
authors.lastname: Rhee
authors.forename: Banchob
authors.initials: B
authors.lastname: Sripa
authors.forename: Chariya
authors.initials: C
authors.lastname: Hahnvajanawong
authors.forename: Seung-Chul
authors.initials: SC
authors.lastname: Baik
mesh_terms: D017209:Apoptosis / Q000187:drug effects*; D001650:Bile Duct Neoplasms / Q000378:metabolism; D001653:Bile Ducts, Intrahepatic; D001659:Biliary Tract / Q000166:cytology*; D045744:Cell Line, Tumor; D002470:Cell Survival; D018281:Cholangiocarcinoma / Q000378:metabolism; D004247:DNA / Q000096:biosynthesis; D004797:Enzyme-Linked Immunosorbent Assay; D015972:Gene Expression Regulation, Neoplastic; D016480:Helicobacter pylori / Q000201:enzymology*; D006801:Humans; D007249:Inflammation / Q000378:metabolism*; D016209:Interleukin-8 / Q000235:genetics / Q000378:metabolism; D052247:Nitric Oxide Synthase Type II / Q000235:genetics / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D005723:gamma-Glutamyltransferase / Q000235:genetics / Q000378:metabolism / Q000494:pharmacology*
chemical_list: C508606:CXCL8 protein, human; D016209:Interleukin-8; D004247:DNA; D052247:Nitric Oxide Synthase Type II; D005723:gamma-Glutamyltransferase