环氧合酶-2在食管癌、胃癌、贲门癌的表达比较

目的　研究环氧合酶2(Cox 2)蛋白及其mRNA在食管癌、胃癌、贲门癌中的表达量和细胞内定位的异同,探讨Cox 2抑制剂对贲门癌的预防作用。方法　免疫组化法定量检测了3 种肿瘤共48 例标本的Cox 2 蛋白,RT PCR法和原位PCR法检测了其中29 例标本的Cox 2mRNA及其在组织细胞内的定位。结果　食管癌、胃癌、贲门癌的Cox 2染色分数分别为4.15±1.39, 3.66±1.16, 2.93±1.03,均高于正常组织。贲门癌的染色分数与胃癌的无显著性差异。Cox 2mRNA在贲门癌的检出率为87.5%(ISPCR),75%(RT PCR),在胃癌、食管癌的检出率为100%,无显著性差异。Cox 2mRNA位于癌细胞胞浆,胞核中也有少量存在,其在3 种肿瘤中相同。结论　Cox 2 在贲门癌中显著升高,其表达特点与胃癌、食管癌中基本相同。Cox 2抑制剂对贲门癌可能有预防作用。

Comparison of the Cox-2 expression in esophageal, gastric and cardia carcinomas

Objective To determine whether Cox-2 inhibitor can reduce the risk of cardia carcinoma. Methods Paraffin-embedded specimens from 48 patients with esophageal, gastric or cardia carcinomas were analyzed by immunohistochemistry for expression of Cox-2 protein. Expression of Cox-2mRNA was assessed by RT-PCR and ISPCR in 29 cases of them. None of these patients were currently taking NSAIDs or glucocorticoid. Results The staining scores were 4.15±1.9 in the group with esophageal cancer, 3.66±1.16 in the group with gastric cancer, and 2.93±1.03 in the group with cardia cancer, respectively. There was no significant difference between groups of gastric cancer and cardia cancer. The ratio of cases with positive expression of Cox-2 mRNA was 87.5% in the group with cardia carcinoma, 100% in the group with esophageal cancer and the group with gastric cancer. And no significant difference was found between them. Cox-2mRNA was mainly located in cytoplasm but was found in nuclear too. No difference was found in the location of Cox-2 expression in the three kinds of cancers. Conclusion Cox-2 expression in cardia carcinoma was higher than in the normal group. Its pathological characteristics were almost the same as those in gastric and esophageal cancers. Cox-2 inhibitor possibly have a chemopreventive effect on cardia carcinoma.