COX-2蛋白在胃粘膜癌前病变与胃癌中表达的意义

Expression of Cyclooxygenase-2 protein in precancerous lesion of gastric mucosa and in gastric carcinoma

目的探讨环氧合酶2(COX2)蛋白在胃粘膜肠上皮化生、非典型增生及胃癌中的表达情况。方法选择幽门螺杆菌(Hp)感染的具有不同病变胃粘膜的胃癌手术切除标本,根据病理结果分组为肠上皮化生、不典型增生、肠型胃癌(各51例)和弥漫型胃癌32例。用免疫组化方法测定各组中COX2蛋白表达情况。比较COX2蛋白在上述各组中的表达强度并与正常粘膜对照。结果正常粘膜和弥漫型胃癌COX2蛋白表达均为阴性。肠上皮化生、非典型增生、肠型胃癌COX2蛋白阳性率分别为58.82%(30/51)、64.71%(33/51)、84.31%(43/51),表达强度组间均有显著性差异(P<0.05)。结论COX2在Hp感染的肠型胃癌发展的早期阶段即开始表达,且在肠型胃癌的发生发展过程中表达水平逐渐增高。

Objective To study the expression of cyclooxygenase-2 protein in intestinal metaplasia(IM),atypical hyperplasia and gastric carcinoma.Methods Specimens were taken around the edge of the tumor associated with infection of Hp.The specimens were grouped pathologically into IM,atypical hyperplasia,intestinal-type gastric cancer and diffuse-type gastric cancer,with 51 cases in each group. The expression of COX-2 protein was evaluated by immunohistochemistry (IHC) in various groups mentioned above. Meanwhile,the intensity of COX-2 expression was examined.The adjacent normal gastric epithelium acts as control group.Results The expression of COX-2 protein was localized in the cytoplasm and nuclear membrane of glandular epithelial cells, but not in infra-layer of mucous membrane.Normal gastric epithelium and diffuse-type gastric carcinoma were negative for the expression of COX-2 protein. The positive rates of IM group, atypical hyperplasia group and intestinal-type of gastric cancer group were 58.82%(30/51),64.71%(33/51)and 84.31%(43/51)respectively(P<0.05).Conclusion The expression of COX-2 protein presents at the early stage of gastric carcinoma associated with Hp infection and the expression is progressively increasing remains in the progressive process of intestinal-type gastric carcinoma.