Hp感染者胃粘膜癌前病变细胞凋亡与Fas抗原表达的关系

目的　研究幽门螺杆菌 (Hp)感染后胃粘膜癌前病变中Fas抗原表达状态及其与细胞凋亡的关系 ,了解Hp在胃癌发生过程中的作用。方法　采用免疫组织化学等方法检测 83例经病理证实为慢性胃炎患者胃粘膜上皮细胞中Fas抗原的表达情况 ,并采用凋亡细胞原位检测方法对组织切片中的凋亡细胞进行观察和比较。结果　在浅表性胃炎、萎缩性胃炎、肠化生及异型增生中 ,Fas抗原表达率分别为 2 0 .0 0 %、36 .36 %、73.33%、4 3.75 % ,Fas抗原在肠化生组织中的表达率显著高于浅表性胃炎、萎缩性胃炎及异型增生 (P <0 .0 1及P <0 .0 5 )。Hp感染者Fas抗原表达率为 6 0 .71% ,显著高于未感染者的 2 2 .2 2 % (P <0 .0 1)。在萎缩、肠化生及异型增生等癌前病变中 ,Hp感染者与未感染者Fas抗原表达率分别为 6 5 .96 %及 2 8.5 7% (P <0 .0 1)。凋亡细胞原位检测结果显示 ,Fas抗原表达阳性肠化生和异型增生组织中的凋亡细胞指数显著高于Fas抗原阴性组 (P <0 .0 5及P <0 .0 1)。结论　Hp感染对Fas抗原表达有一定的影响 ,Fas基因对胃粘膜上皮细胞凋亡具有促进性调控作用 ,Hp感染可促进Fas抗原表达增加 ,这可能是Hp感染诱导胃粘膜上皮细胞凋亡的机制之一。

The relationship between Helicobacter pylori and expression of Fas antigen and apoptosis in gastric precancerous lesions

Objectives To determine whether there is a relationship between the presence of Hp and the expression of Fas antigen and apoptosis, and to estimate the role of Hp in the development of gastric carcinoma. Methods Using immunohistochemical staining, we studied the expression rate of Fas antigen in 83 patients with histopathologically proven chronic gastritis.Meanwhile, an in situ apoptotic cell detection method was adopted to detect the apoptotic cells in these lesions, and the number of apoptotic cells was compared with the Fas gene expression in each case.Results For chronic superficial gastritis,chronic atrophic gastritis, intestinal metaplasia and dysplasia, the expression rate of Fas antigen was 20.00%, 36.36%, 73.33% and 43.75% respectively. The expression rate of Fas antigen in intestinal metaplasia was significantly higher than that in chronic superficial gastritis, chronic atrophic gastritis and dysplasia ( P <0.01 and P <0.05). The positive rates of Fas antigen were higher among patients infected with Hp than those with no Hp infection (60.71% vs 22.22%).In the precancerous lesions of cellular atrophy, intestinal metaplasia and dysplasia,the expression rates of Hp infected patients were significantly higher (65.96%)than those of Hp negative patients(28.57%, P <0.01). Comparing the Fas antigen expression and apoptotic cell number in intestinal metaplasia and dysplasia, we found that the apoptotic index in Fas antigen expression positive group was higher than that in Fas antigen negative group( P <0.01 and P <0.05). Conclusion The results suggest that Hp is involved in the expression of Fas gene. Fas gene can promote apoptosis in gastric precancerous lesions. Hp infection increases the expression of Fas antigen,this may be one of the mechanisms of Hp infection induced gastric epithelial cell apoptosis.