<i>Helicobactor pylori</i> Infection Is Closely Associated with Telomere Reduction in Gastric Mucosa

Abstract

OBJECTIVE: To investigate differential reduction in telomere DNA in tissue components of gastric mucosa with respect to Helicobactor pylori infection. MATERIALS AND METHODS: The telomere content was examined by fluorescent in situ hybridization with the (TTAGGG)(4) probe. To compare the signal intensities from the probe (telomere volume) with telomere length, five gastric carcinoma cell lines were used. Telomere volumes were examined in 9 healthy persons, 124 non-cancer patients, and 86 gastric cancer patients. RESULTS: Telomere volume showed a linear correlation with telomere length measured by Southern blotting in gastric carcinoma cells. In healthy persons without H. pylori infection, the telomere volumes of gastric epithelial tissues were 70-79% that of intramucosal lymphocytes (internal control). In 124 patients without gastric cancer, telomere volume of H.-PYLORI-infected mucosa was significantly less than that of H.-pylori-negative mucosa in both metaplastic and non- metaplastic tissues (p < 0.0001). In 86 gastric cancer patients, telomere volumes in intestinal metaplasia adjacent to cancer were 75% that of intestinal metaplasia of non-cancer patients (p = 0.0001). hTERT expression was detected in 6 cancer-associated and 2 cancer-negative intestinal metaplasia specimens, in which telomere volume was markedly reduced. CONCLUSION: H. pylori infection is closely associated with telomere reduction in gastric epithelium.