AgNOR and rasp21 expression in gastric mucosal lesions with Helicobacter pylori infection

IM To study the number of AgNOR and rasp21 expression in different gastric mucosal lesions with Helicobacter pylori (Hp) infection to evaluate their biological behaviour and possible mechanism of Hp. METHODS Hp (using CLO test combined with WathinStarry staining), AgNOR (silver colloid technique) and rasp21 (monoclonal antibody and immunohistochemical staining—ABC method) were detected in 278 patients with endoscopically and pathologically confirmed gastric mucosal lesions, including chronic superficial gastritis (CSG), chronic atrophic gastritis (CAG), intestinal metaplasia (IM), dysplasia (Dys), and gastric cancer (GC). Among them, 146 cases were Hp positive, and 132 cases Hp negative. RESULTS The mean number of AgNOR in Hp positive group was significantly higher than that in Hp negative group in the gastric mucosal lesions except for CSG (P<005 or P<001). The positive rate of rasp21 expression in Hp positive group was also significantly higher than that in Hp negative group in gastric mucosal lesions except for CSG and CAG (P<005).CONCLUSION Hp+ gastric mucosal lesions have more biological behaviour of tumors. Hp may act as a promoter to activate ras gene and to stimulate cell over proliferation.

Study on the Association Between Helicobacter Pylori Infection and the Pathogenesis of Gastric Cancer by Using Molecuar Biological Techniques

Recent epidemiological observations have indicated that the role of Helicobacter pylori (HP) infection in the pathogenesis of gastric cancer is an important but unresolved issue. We used the polymerase chain reaction, a sensitive and specific assay, to detect the HP infection in gastric biopsy specimens and examined the corrclations between HP infection and point mutation at 12 codon of H-ras oncogeneHras oncogene is higher in the group with HP infection than in those without HP infection. Furthermore, there is strong evidence that HP infection is associated with the increased expression of ras p21 protein , which suggested that HP infection increased the risk of ras oncogene activation. It is also noted that a significant relationship between infection with HP and the increase of DNA content and s% phase cells, indicated that rapid turnover of cells resulting from infection injury increases the risk of DNA damage.

幽门螺杆菌L型感染与PCNA、P^(21)、P^(53)表达关系的探讨

目的：探讨幽门螺杆菌L型（Hp-L型）可能的致癌机理。方法：应用免疫组化S-P法对Hp-L型阳性和阴性胃病变组织的PCNA、P21、P53表达进行对比分析。结果：胃癌、癌前病变的PCNA、P21、P53表达显著高于慢性浅表性胃炎和正常粘膜；Hp-L型阳性组的PCNA、P21、P53表达也明显高于Hp-L型阴性组（P＜0．01，P＜0·05）。表明Hp-L型感染与胃病变组织的PCNA、P21、P53过度表达存在着相关性。提示，Hp-L型感染时胃粘膜处于高增殖状态。结论：Hp-L型参与了ras原癌基因激活和P53抑癌基因的失活，基因突变可能是Hp-L型致胃癌作用的机制之一。

P_(21)^(ras)在胃良、恶性病变中的表达及与幽门螺旋杆菌感染的关系

本文Ｐ２１ｒａｓ免疫组化采用链霉菌抗生物素蛋白——过氧化酶（ＳＰ）法检测了６１例胃粘膜标本。结果表明胃癌（５６．０％）与胃癌前病变（６０．０％）阳性率高于胃良性病变（１４．０％），Ｐ值分别＜０．０５与＜０．００５。并进行了诊断胃癌价值评估，其敏感性、特异性和准确性分别为５６．０％，６６．７．与６２．３％，说明Ｐ２１ｒａｓ诊断胃癌有一定价值。同时检测了幽门螺旋杆菌（ＨＰ），计算Ｐ２１ｒａｓ阳性与ＨＰ感染的相关系数为０．８７９，呈正相关。

胃幽门螺杆菌与胃癌发病机制关系的分子生物学研究

近期流行病学研究已发现胃幽门螺杆菌(HP)是胃癌发生的重要始发因素。本文应用敏感特异的聚合酶链反应(PCR)方法检测胃粘膜组织HP,分析其与C—Ha—ras第12位密码子点突变,ras基因产物P^(21)蛋白表达及DNA倍体的关系。发现C—Ha—ras点突变率于HP阳性组高于阴性组,并且HP阳性组较HP阴性组出现rasP^(21)表达增强,说明HP感染与C—Ha—ras基因活化有关,HP感染后DNA含量及S％期细胞明显增高,提示核苷酸代谢旺盛,DNA损伤及非整倍体的危险性也增高。本研究为HP致胃癌的可能机制从分子水平及细胞代谢水平作了初步研究。