H. pylori expressing high Trx1 significantly induced cell apoptosis, decreased the expression of cyclin D1 and up-regulated p21 in GES-1. However, in BGC823, it increased cell proliferation, and up-regulated cyclin D1. These imply
that the effects of H. pylori were different in the developing stages of gastric cancer. In vivo, we found that H. pylori expressing high Trx1 was much more high pathogenic. Mongolian gerbils were infected by H. pylori expressing high Trx1 for 91 weeks, resulting Selleckchem BGB324 in significantly more serious pathological changes in the gastric mucosa, including gastric cancer and atypical hyperplasia. Conclusion: High Trx1 expression in H. pylori is associated with gastric carcinogenesis. In H. pylori, Trx1 likely participates in find more the pathogenesis of gastric cancer and might be a novel risk marker for highly toxic H. pylori. Key Word(s): 1. Helicobacter pylori; 2. gastric cancer; 3. thioredoxin; Presenting Author: YANYAN SHI Additional Authors: MO CHEN, LINNA LIU, JING ZHANG, YE WANG, SHIGANG DING Corresponding Author: SHIGANG DING Affiliations: Peking University Third Hospital Objective: Helicobacter pylori (H. pylori) maintains long-term persistence in the host and combats oxidative stress via diverse antioxidant proteins, which are expected to be relevant to bacterial-associated diseases. The antioxidant system
in H. pylori is complex and has not been clear. We aim to investigate the expression of three essential antioxidants in H. pylori isolated from patients of different clinical outcomes. Methods: Forty H. pylori strains were isolated from endoscopic biopsy specimens of gastric mucosa from ten patients displaying gastric cancer, twelve patients displaying peptic ulcer, and eleven patients displaying gastritis. After RNA isolation and reverse transcription, the expressions of arginase (RocF), alkyl hydroperoxide reductase (AhpC) and thioredoxin 1 (Trx1) in H. pylori 17-DMAG (Alvespimycin) HCl were
measured by real-time PCR. Comparisons between multiple sample sets were analyzed using a one-way ANOVA test. Pearson’s correlation test was used to assess relationships between multiple continuous variables. Results: RocF expression of H. pylori in gastric cancer tissues was higher than gastritis (P < 0.05). Trx1 expression of H. pylori in gastric cancer (P < 0.05) and peptic ulcer (P < 0.05) tissues was higher than gastritis. The expressions of RocF and Trx1 had positive correlation (r = 0.411, P < 0.05). These indicated that RocF and Trx1 might be related with each other and involved in gastric carcinogenesis. However, we did not find any difference of AhpC expression in different clinical outcomes and any correlation with other two genes. Conclusion: Trx1 and RocF expressions of H. pylori in clinical gastric cancer tissues were higher than in tissues with gastritis. In H. pylori, the members of antioxidant system likely correlate with each other and are relevant to gastric cancer. Key Word(s): 1.