title: Helicobacter pylori-induced inflammation and epigenetic changes during gastric carcinogenesis.
abstract: The sequence of events associated with the development of gastric cancer has been described as "the gastric precancerous cascade". This cascade is a dynamic process that includes lesions, such as atrophic gastritis, intestinal metaplasia and dysplasia. According to this model, Helicobacter pylori (H. pylori) infection targets the normal gastric mucosa causing non-atrophic gastritis, an initiating lesion that can be cured by clearing H. pylori with antibiotics or that may then linger in the case of chronic infection and progress to atrophic gastritis. The presence of virulence factors in the infecting H. pylori drives the carcinogenesis process. Independent epidemiological and animal studies have confirmed the sequential progression of these precancerous lesions. Particularly long-term follow-up studies estimated a risk of 0.1% for atrophic gastritis/intestinal metaplasia and 6% in case of dysplasia for the long-term development of gastric cancer. With this in mind, a better understanding of the genetic and epigenetic changes associated with progression of the cascade is critical in determining the risk of gastric cancer associated with H. pylori infection. In this review, we will summarize some of the most relevant mechanisms and focus predominantly but not exclusively on the discussion of gene promoter methylation and miRNAs in this context.
authors.affiliation: Manuel A Valenzuela, Jimena Canales, Andrew FG Quest, Laboratorio de Comunicaciones Celulares, Centro de Estudios Moleculares de la Célula, Programa de Biología Celular y Molecular, ICBM, Facultad de Medicina, Universidad de Chile, Santiago 8380453, Chile.
authors.forename: Manuel A
authors.initials: MA
authors.lastname: Valenzuela
authors.affiliation: Manuel A Valenzuela, Jimena Canales, Andrew FG Quest, Laboratorio de Comunicaciones Celulares, Centro de Estudios Moleculares de la Célula, Programa de Biología Celular y Molecular, ICBM, Facultad de Medicina, Universidad de Chile, Santiago 8380453, Chile.
authors.forename: Jimena
authors.initials: J
authors.lastname: Canales
authors.affiliation: Manuel A Valenzuela, Jimena Canales, Andrew FG Quest, Laboratorio de Comunicaciones Celulares, Centro de Estudios Moleculares de la Célula, Programa de Biología Celular y Molecular, ICBM, Facultad de Medicina, Universidad de Chile, Santiago 8380453, Chile.
authors.forename: Alejandro H
authors.initials: AH
authors.lastname: Corvalán
authors.affiliation: Manuel A Valenzuela, Jimena Canales, Andrew FG Quest, Laboratorio de Comunicaciones Celulares, Centro de Estudios Moleculares de la Célula, Programa de Biología Celular y Molecular, ICBM, Facultad de Medicina, Universidad de Chile, Santiago 8380453, Chile.
authors.forename: Andrew F G
authors.initials: AF
authors.lastname: Quest
mesh_terms: D000818:Animals; D001426:Bacterial Proteins / Q000378:metabolism; D018797:Cell Cycle Proteins / Q000235:genetics; D002471:Cell Transformation, Neoplastic / Q000235:genetics / Q000473:pathology; D004249:DNA Damage; D019175:DNA Methylation; D044127:Epigenesis, Genetic; D005753:Gastric Mucosa / Q000382:microbiology* / Q000473:pathology; D005756:Gastritis / Q000175:diagnosis / Q000235:genetics / Q000382:microbiology*; D015972:Gene Expression Regulation, Neoplastic; D006023:Glycoproteins / Q000235:genetics; D016481:Helicobacter Infections / Q000150:complications / Q000175:diagnosis / Q000235:genetics / Q000382:microbiology*; D016480:Helicobacter pylori / Q000201:enzymology / Q000472:pathogenicity*; D054884:Host-Pathogen Interactions; D006801:Humans; D035683:MicroRNAs / Q000235:genetics; D011230:Precancerous Conditions / Q000175:diagnosis / Q000235:genetics / Q000382:microbiology*; D013274:Stomach Neoplasms / Q000175:diagnosis / Q000235:genetics / Q000378:metabolism*; D014774:Virulence; D005722:gamma-Glutamylcyclotransferase / Q000378:metabolism
chemical_list: D001426:Bacterial Proteins; D018797:Cell Cycle Proteins; D006023:Glycoproteins; D035683:MicroRNAs; C412566:RPRM protein, human; D005722:gamma-Glutamylcyclotransferase
keywords: Epigenetics; Gastric cancer; Helicobacter pylori; Methylation; MicroRNA