Department of gastroenterology, The First Affiliated Hospital, Nanchang university, Nanchang, 330006, Jiangxi, China.
Clin Res Hepatol Gastroenterol. 2012 Jun;36(3):235-43. doi: 10.1016/j.clinre.2011.11.009. Epub 2012 Feb 3.
To explore the association of p53-MDM2 feedback loop related proteins with gastric pathologies in relation to Helicobacter pylori infection.
Gastric biopsies were obtained from 157 H. pylori-negative and positive patients, including normal gastric mucosa (NGM), chronic gastritis (CG), intestinal metaplasia (IM), dysplasia (Dys), and gastric cancer (GC). The expression of mutant p53, MDM2, Bax and PUMA in gastric tissues was detected by immunohistochemistry.
Overall expression of MDM2 and Bax is progressively increased from NGM to GC. PUMA expression is increased in CG but subsequently decreased after the development of IM. H. pylori infection is associated with increased mutant p53 and Bax expression but decreased PUMA expression in IM, and increased MDM2 expression in Dys.
These results suggest that different p53-MDM2 feedback loop related proteins are distinctly expressed in the various stages of gastric carcinogenesis; their roles in gastric carcinogenesis in the presence of H. pylori infection need to be further investigated.
探讨 p53-MDM2 反馈回路相关蛋白与幽门螺杆菌感染相关胃病变的关系。
从 157 例 H. pylori 阴性和阳性患者中获取胃活检组织，包括正常胃黏膜（NGM）、慢性胃炎（CG）、肠上皮化生（IM）、异型增生（Dys）和胃癌（GC）。采用免疫组织化学法检测胃组织中突变型 p53、MDM2、Bax 和 PUMA 的表达。
MDM2 和 Bax 的总体表达水平从 NGM 逐渐升高至 GC。CG 中 PUMA 的表达增加，但在发生 IM 后表达降低。H. pylori 感染与 IM 中突变型 p53 和 Bax 表达增加以及 PUMA 表达降低，以及 Dys 中 MDM2 表达增加相关。
这些结果表明，不同的 p53-MDM2 反馈回路相关蛋白在胃癌变的不同阶段有明显不同的表达；在 H. pylori 感染存在的情况下，它们在胃癌变中的作用需要进一步研究。
