title: Activation of EGFR and ERBB2 by Helicobacter pylori results in survival of gastric epithelial cells with DNA damage.
abstract: OBJECTIVE
  The gastric cancer-causing pathogen Helicobacter pylori up-regulates spermine oxidase (SMOX) in gastric epithelial cells, causing oxidative stress-induced apoptosis and DNA damage. A subpopulation of SMOX(high) cells are resistant to apoptosis, despite their high levels of DNA damage. Because epidermal growth factor receptor (EGFR) activation can regulate apoptosis, we determined its role in SMOX-mediated effects.
  
  
  METHODS
  SMOX, apoptosis, and DNA damage were measured in gastric epithelial cells from H. pylori-infected Egfr(wa5) mice (which have attenuated EGFR activity), Egfr wild-type mice, or in infected cells incubated with EGFR inhibitors or deficient in EGFR. A phosphoproteomic analysis was performed. Two independent tissue microarrays containing each stage of disease, from gastritis to carcinoma, and gastric biopsy specimens from Colombian and Honduran cohorts were analyzed by immunohistochemistry.
  
  
  RESULTS
  SMOX expression and DNA damage were decreased, and apoptosis increased in H. pylori-infected Egfr(wa5) mice. H. pylori-infected cells with deletion or inhibition of EGFR had reduced levels of SMOX, DNA damage, and DNA damage(high) apoptosis(low) cells. Phosphoproteomic analysis showed increased EGFR and erythroblastic leukemia-associated viral oncogene B (ERBB)2 signaling. Immunoblot analysis showed the presence of a phosphorylated (p)EGFR-ERBB2 heterodimer and pERBB2; knockdown of ErbB2 facilitated apoptosis of DNA damage(high) apoptosis(low) cells. SMOX was increased in all stages of gastric disease, peaking in tissues with intestinal metaplasia, whereas pEGFR, pEGFR-ERBB2, and pERBB2 were increased predominantly in tissues showing gastritis or atrophic gastritis. Principal component analysis separated gastritis tissues from patients with cancer vs those without cancer. pEGFR, pEGFR-ERBB2, pERBB2, and SMOX were increased in gastric samples from patients whose disease progressed to intestinal metaplasia or dysplasia, compared with patients whose disease did not progress.
  
  
  CONCLUSIONS
  In an analysis of gastric tissues from mice and patients, we identified a molecular signature (based on levels of pEGFR, pERBB2, and SMOX) for the initiation of gastric carcinogenesis.
authors: Division of Gastroenterology, Hepatology, and Nutrition, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee.
authors: Rupesh
authors: R
authors: Chaturvedi
authors: Division of Gastroenterology, Hepatology, and Nutrition, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee; Veterans Affairs Tennessee Valley Healthcare System, Nashville, Tennessee.
authors: Mohammad
authors: M
authors: Asim
authors: Division of Gastroenterology, Hepatology, and Nutrition, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee.
authors: M Blanca
authors: MB
authors: Piazuelo
authors: Division of Gastroenterology, Department of Pediatrics, Vanderbilt University Medical Center, Nashville, Tennessee.
authors: Fang
authors: F
authors: Yan
authors: Division of Gastroenterology, Hepatology, and Nutrition, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee; Veterans Affairs Tennessee Valley Healthcare System, Nashville, Tennessee.
authors: Daniel P
authors: DP
authors: Barry
authors: Division of Gastroenterology, Hepatology, and Nutrition, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee.
authors: Johanna Carolina
authors: JC
authors: Sierra
authors: Division of Gastroenterology, Hepatology, and Nutrition, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee.
authors: Alberto G
authors: AG
authors: Delgado
authors: Mass Spectrometry Research Center, Vanderbilt University Medical Center, Nashville, Tennessee.
authors: Salisha
authors: S
authors: Hill
authors: Department of Oncology, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, Maryland.
authors: Robert A
authors: RA
authors: Casero
authors: Department of Pathology, Universidad del Valle School of Medicine, Cali, Colombia.
authors: Luis E
authors: LE
authors: Bravo
authors: Hospital de Occidente, Santa Rosa de Copan, Copan, Honduras.
authors: Ricardo L
authors: RL
authors: Dominguez
authors: Division of Gastroenterology, Hepatology, and Nutrition, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee.
authors: Pelayo
authors: P
authors: Correa
authors: Division of Gastroenterology, Department of Pediatrics, Vanderbilt University Medical Center, Nashville, Tennessee; Department of Pediatrics, University of Southern California Keck School of Medicine, Los Angeles, California.
authors: D Brent
authors: DB
authors: Polk
authors: Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee.
authors: M Kay
authors: MK
authors: Washington
authors: Mass Spectrometry Research Center, Vanderbilt University Medical Center, Nashville, Tennessee.
authors: Kristie L
authors: KL
authors: Rose
authors: Mass Spectrometry Research Center, Vanderbilt University Medical Center, Nashville, Tennessee; Department of Biochemistry, Vanderbilt University Medical Center, Nashville, Tennessee.
authors: Kevin L
authors: KL
authors: Schey
authors: Division of Gastroenterology, Hepatology, and Nutrition, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee.
authors: Douglas R
authors: DR
authors: Morgan
authors: Division of Gastroenterology, Hepatology, and Nutrition, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee; Veterans Affairs Tennessee Valley Healthcare System, Nashville, Tennessee; Department of Cancer Biology, Vanderbilt University Medical Center, Nashville, Tennessee.
authors: Richard M
authors: RM
authors: Peek
authors: Division of Gastroenterology, Hepatology, and Nutrition, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee; Veterans Affairs Tennessee Valley Healthcare System, Nashville, Tennessee; Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee; Department of Cancer Biology, Vanderbilt University Medical Center, Nashville, Tennessee. Electronic address: keith.wilson@vanderbilt.edu.
authors: Keith T
authors: KT
authors: Wilson
mesh_terms: D000818:Animals; D017209:Apoptosis; D002460:Cell Line; D002470:Cell Survival; D002471:Cell Transformation, Neoplastic / Q000378:metabolism / Q000473:pathology; D018920:Coculture Techniques; D003105:Colombia; D004249:DNA Damage; D018450:Disease Progression; D004789:Enzyme Activation; D004847:Epithelial Cells / Q000201:enzymology* / Q000382:microbiology / Q000473:pathology; D066246:ErbB Receptors / Q000172:deficiency / Q000235:genetics / Q000378:metabolism*; D005753:Gastric Mucosa / Q000201:enzymology* / Q000382:microbiology / Q000473:pathology; D005756:Gastritis / Q000201:enzymology / Q000382:microbiology / Q000473:pathology; D016481:Helicobacter Infections / Q000201:enzymology* / Q000235:genetics / Q000382:microbiology / Q000473:pathology; D016480:Helicobacter pylori / Q000378:metabolism* / Q000472:pathogenicity; D006721:Honduras; D006801:Humans; D008679:Metaplasia; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D000587:Oxidoreductases Acting on CH-NH Group Donors / Q000378:metabolism; D010766:Phosphorylation; D011230:Precancerous Conditions / Q000201:enzymology / Q000382:microbiology / Q000473:pathology; D025341:Principal Component Analysis; D055503:Protein Multimerization; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000235:genetics / Q000378:metabolism*; D015398:Signal Transduction; D013274:Stomach Neoplasms / Q000201:enzymology / Q000382:microbiology / Q000473:pathology; D013714:Tennessee; D000097667:Polyamine Oxidase
chemical_list: D066246:ErbB Receptors; D000587:Oxidoreductases Acting on CH-NH Group Donors; D018719:Erb-b2 Receptor Tyrosine Kinases; D000097667:Polyamine Oxidase; C512478:EGFR protein, human; C541485:EGFR protein, mouse; C508053:ERBB2 protein, human; C524056:Erbb2 protein, mouse
keywords: Marker; Prognostic Factor; Risk; Signal Transduction Pathways