title: Heat shock protein 27 expression is inversely correlated with atrophic gastritis and intraepithelial neoplasia.
abstract: BACKGROUND
  Intestinal-type gastric carcinomas progress through several sequential steps, including atrophic gastritis, intestinal metaplasia, dysplasia, and cancer.
  
  
  OBJECTIVE
  We investigated heat shock protein 27 (HSP27) expression in gastric neoplasia and background gastric mucosa to assess its involvement in gastric carcinogenesis.
  
  
  METHODS
  We used real-time quantitative polymerase chain reaction to examine HSP27 expression in gastric neoplasias and background gastric mucosae of 30 patients with intraepithelial neoplasias and in gastric mucosae of 30 patients without gastric neoplasia. Immunohistochemical staining was performed on 30 advanced gastric cancer tissues.
  
  
  RESULTS
  HSP27 expression was negatively associated with atrophic gastritis. HSP27 expression in the background gastric mucosa of neoplasia-bearing patients was significantly lower than in the mucosa of those without gastric neoplasia. In tumor necrosis factor α-treated gastric cancer cells, HSP27 knockdown increased cell death and accumulation of the reactive oxygen species that link inflammation to cancer. Poorly differentiated tumors most frequently had high HSP27 levels. Dedifferentiation of cancer cells is associated with an epithelial-mesenchymal transition (EMT) signaling pathway. In gastric cancer MKN-1 cells, HSP27 knockdown upregulated E-cadherin and downregulated vimentin and smooth muscle actin, but this did not occur in MKN-74 cells.
  
  
  CONCLUSIONS
  HSP27 expression in gastric mucosae is inversely correlated with intraepithelial neoplasia, a probable precursor to gastric cancer, and HSP27 expression in cancer is positively correlated with poor differentiation.
authors.affiliation: Department of Gastroenterology and Hepatology, Faculty of Medicine, Kinki University, 377-2, Ohno-Higashi, Osaka-Sayama, Osaka, 589-8511, Japan.
authors.forename: Yoshiaki
authors.initials: Y
authors.lastname: Nagata
authors.forename: Masatoshi
authors.initials: M
authors.lastname: Kudo
authors.forename: Tomoyuki
authors.initials: T
authors.lastname: Nagai
authors.forename: Tomohiro
authors.initials: T
authors.lastname: Watanabe
authors.forename: Masanori
authors.initials: M
authors.lastname: Kawasaki
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Asakuma
authors.forename: Satoru
authors.initials: S
authors.lastname: Hagiwara
authors.forename: Naoshi
authors.initials: N
authors.lastname: Nishida
authors.forename: Shigenaga
authors.initials: S
authors.lastname: Matsui
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Kashida
authors.forename: Toshiharu
authors.initials: T
authors.lastname: Sakurai
mesh_terms: D000230:Adenocarcinoma / Q000235:genetics* / Q000401:mortality / Q000473:pathology; D053687:Adult Stem Cells / Q000473:pathology / Q000502:physiology; D000368:Aged; D014408:Biomarkers, Tumor / Q000235:genetics; D002278:Carcinoma in Situ / Q000235:genetics* / Q000401:mortality / Q000473:pathology; D002294:Carcinoma, Squamous Cell / Q000235:genetics* / Q000401:mortality / Q000473:pathology; D016923:Cell Death / Q000187:drug effects / Q000502:physiology; D054337:Cell Dedifferentiation / Q000502:physiology; D002454:Cell Differentiation / Q000502:physiology; D045744:Cell Line, Tumor; D005260:Female; D005753:Gastric Mucosa / Q000473:pathology / Q000502:physiology; D005757:Gastritis, Atrophic / Q000235:genetics* / Q000401:mortality / Q000473:pathology; D015972:Gene Expression Regulation, Neoplastic; D055551:HSP27 Heat-Shock Proteins / Q000235:genetics*; D006360:Heat-Shock Proteins; D006801:Humans; D008297:Male; D018832:Molecular Chaperones; D060787:Neoplasm Grading; D017382:Reactive Oxygen Species / Q000378:metabolism; D013274:Stomach Neoplasms / Q000235:genetics* / Q000401:mortality / Q000473:pathology; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology
chemical_list: D014408:Biomarkers, Tumor; D055551:HSP27 Heat-Shock Proteins; C057725:HSPB1 protein, human; D006360:Heat-Shock Proteins; D018832:Molecular Chaperones; D017382:Reactive Oxygen Species; D014409:Tumor Necrosis Factor-alpha