胃黏膜病变演化过程中幽门螺杆菌感染与p53变异和MG-7抗原及核仁组成区相关蛋白表达的关系

The relation between Helicobacter pylori infection and p53 mutation,MG-7 antigen and AgNORs expression in the development of gastric mucosa lesions

目的 从胃黏膜细胞增殖、基因变异、胃癌特异性抗原表达的角度探讨幽门螺杆菌(Hp)感染 ,特别是cagA阳性Hp感染在胃黏膜病变演化中的作用。 方法 根据组织形态学和黏液组织化学检查将 10 9例临床标本分为Ⅰ型肠化、Ⅱ型肠化、Ⅲ型肠化、非典型增生和胃癌 5个组 ;用显微切割 /PCR方法检测标本中的Hp ,并将其分为cagA阳性和cagA阴性两组 ;用免疫组化方法检测 p5 3蛋白、MG 7抗原的表达 ;用组织化学银染检测核仁组成区相关蛋白 (AgNORs)的表达。结果 (1)P5 3在各组均有表达 ,其中胃癌组P5 3的表达率明显高于其他各组 (P <0 .0 5 )。 (2 )胃癌组MG 7的总表达率与过表达率均明显高于其他各组。在各组胃黏膜病变中 ,Hp阳性与阴性标本MG7表达无明显差异。在各组病变中cagA阳性组与cagA阴性组MG7的表达无明显差异。 (3)Ⅰ型和Ⅱ型肠化→Ⅲ型肠化→非典型增生→胃癌的演变过程中 ,AgNORs平均计数明显增高 (P <0 .0 5 )。各胃黏膜病变组中Hp阳性标本AgNORs计数明显高于Hp阴性标本 (P <0 0 5 )。在Hp阳性的标本中 ,cagA阳性标本AgNORs颗粒计数明显高于cagA阴性标本 (P <0 0 5 )。 结论 Hp感染 ,特别是cagA阳性的Hp感染在胃黏膜病变演化的过程中起重要作用 ,其作用机理与促进黏膜细胞增殖有关 ;p5 3变异和MG

Objective To explore the relation between H. pylori infection and the development of gastric mucosa lesions,and to evaluate the effect of H. pylori infection on cell proliferation, p53 mutation, and MG-7 antigen expression in patients with gastric precancerous lesions. Methods One hundred and nine gastric biopsy specimens were divided into five groups of different gastric mucosa lesions according to pathologic findings and the results of mucosa histochemical staining: type Ⅰ intestinal metaplasia (IM), typeⅡIM, type Ⅲ IM, dysplasia (Dys) and gastric cancer (GC). H. pylori and its cagA status were assessed by microdissection/PCR method. Expression of P53 protein and MG-7 antigen were examined by immunohistochemical staining. AgNOR staining was performed for each specimen. Results ①Expression of P53 increased in more severe gastric mucosa lesion groups. The P53 expression rate in GC group was significantly higher than other groups ( P <0.05). There was no difference in expression of P53 between groups of different H. pylori status as while as different cagA status.②The expression of MG-7 in GC group was significantly higher than that in other groups ( P <0.05). There were no difference of expression of MG-7 between subgroups of different H. pylori infection status or cagA status in all groups ( P >0.05). ③The counts of argyrophil protein of the nucleolar organizer regions (AgNORs) were significantly increased in more severe gastric mucosa lesion groups ( P <0.05), and were significantly higher in H. pylori positive and cagA positive specimens than in other specimens ( P <0.05). Conclusions Infection with H. pylori , particularly cagA-positive strains, is associated with the development of more severe gastric mucosa lesions; it seems to have effects on cell proliferation in patients with gastric precancerous lesions. Expression of P53 and MG-7 are earlier events in gastric cancer carcinogenesis.