Role ofHelicobacter Pylori infection in pathogenesis of gastric adenocarcinoma

Abstract

To study the effect ofHelicobacter Pylori (Hp) on the process of gastric carcinogenesis, 35 cases of chronic gastritis, 20 cases of gastric adenocarcinoma were studied by use of transmission electron microscopy, immunohistochemical and molecular biological technique. The results showed that 24 of 35 cases of chronic gastritis were positive for Hp, 11/20 cases of gastric adenocarcinoma wereHp positive. PCNA positive cell labeling index (LI) inHp-associated chronic gastritis (LI= 20. 6±4. 7) Was higher than that inHp negative chronic gastritis (LI = 11.3±5. 2) (P<0. 05). HSP70 expression of gastric adenocarcinoma tissues inHp-infected patients were lower than that of non-Hp-infected gastric cancer. p53 gene mutation was found in gastric adenocarcinoma with positiveHp. It was suggested thatHp may enhance gastric cell proliferation, decrease the expression of HSP70 which induces p53 mutation.

Keywords

helicobacter pylori / chronic gastritis / gastric adenocarcinoma / proliferating cell nuclear antigen / heat shock protein 70 / p53

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