detection of Helicobacter pylori cag pathogenicity islands (PAIs) and expression of matrix metalloproteinase-7 (MMP-7) in gastric epithelial dysplasia and intramucosal cancer

• Published in: Gastric cancer : official journal of the International Gastric Cancer Association and the Japanese Gastric Cancer Association 2010-08, Vol.13 (3), p.162-169
• Main Authors: Chung, Woo Chul, Jung, Sung Hoon, Lee, Kang-Moon, Paik, Chang Nyol, Kawk, Jea Wuk, Jung, Ji Han, Lee, Min Kyoung, Lee, Yun Kyung
• Format: Article
• Language: English
• Subjects: Abdominal Surgery; Antigens, Bacterial - genetics; Antigens, Bacterial - isolation & purification; Bacterial Proteins - genetics; Bacterial Proteins - isolation & purification; Cancer Research; Female; Gastric cancer; Gastric Mucosa - enzymology; Gastric Mucosa - pathology; Gastroenterology; Gastroscopy; Gene Expression Regulation, Bacterial; Gene Expression Regulation, Enzymologic; Genomic Islands; Health Status Indicators; Helicobacter Infections - enzymology; Helicobacter Infections - microbiology; Helicobacter Infections - pathology; Helicobacter pylori; Helicobacter pylori - genetics; Helicobacter pylori - pathogenicity; Humans; Immunohistochemistry; Male; Matrix metalloproteinase; Matrix Metalloproteinase 7 - biosynthesis; Matrix Metalloproteinase 7 - genetics; Medicine; Medicine & Public Health; Middle Aged; Oncology; Original Article; Risk Factors; Stomach Neoplasms - enzymology; Stomach Neoplasms - microbiology; Stomach Neoplasms - pathology; Surgical Oncology; Virulence
• ISSN: 1436-3291; 1436-3305
• DOI: 10.1007/s10120-010-0552-5

Background The cag pathogenicity island (PAI), a Helicobacter pylori virulence factor, is associated with the pathogenesis of gastric cancer. Matrix metalloproteinase-7(MMP-7) is upregulated in the epithelial cells of gastric cancer. To date, there is limited information available on the role of cag PAI and MMP-7 in precursor lesions. In this study, we aimed to identify virulent H. pylori strains and the expression of MMP-7 in samples of gastric epithelial dysplasia and intramucosal cancer. Methods One hundred and twelve tissues excised by endoscopic mucosal resection, 76 specimens with gastric epithelial dysplasia and 36 with intramucosal cancer, were examined. All tissue samples were paired with surrounding normal epithelial tissue samples. We performed polymerase chain reaction for cagA and cagL in neoplasia and paired normal specimens, and assessed the matrix metalloproteinase (MMP)-7 expression by immunohistochemical staining. Results There was a significant difference in the frequencies of cagA or cagL between specimens with gastric dysplasia and those with intramucosal cancer. We confirmed greater expression of MMP-7 immunoreactivity in intramucosal cancers infected with a virulent H. pylori strain. Conclusion Our results suggest that infection with a virulent H. pylori strain was associated with early-stage gastric cancer and that carcinogenesis was associated with cag PAI-dependent MMP-7 upregulation.