[摘要]　目的：探讨环氧合酶-2(COX-2)蛋白在胃癌组织中的表达，并探讨COX-2对P糖蛋白(P-gp)表达的影响。

方法：应用免疫组织化学方法检测48例胃癌及10例正常胃组织中COX-2蛋白与P-gp蛋白的表达。

结果：正常胃组织中未见COX-2表达，胃癌组织中COX-2阳性率为60.4%(29/48)，其阳性表达与肿瘤的TNM分期及淋巴结转移相关(P<0.05)。COX-2阳性组中P-gp表达阳性率为82.8%(24/29)，而COX-2阴性组P-gp同时阴性率63.2%(12/19)，两者有高度正相关性，相关系数r=0.470(P<0.01)。

结论：COX-2蛋白的表达参与胃癌的发生及恶性进展，并可能干预P-gp表达，参与对肿瘤的多药耐药(MDR)的调节作用。

[关键词]　胃癌；环氧合酶-2；多药耐药；P-gp

[Abstract]　Purpose：To investigate the cyclooxygenase-2(COX-2) expression in gastric carcinoma and investigate the effects of COX-2 expression on P-glycoprotein.

Methods：The expression of COX-2 and P-glycoprotein was examined by immunohistochemical staining in 48 cases of gastric carcinoma and 10 cases of normal gastric tissues.

Results：There was no positive signal of COX-2 detected in normal gastric tissue. The positive expression rate of COX-2 was 60.4 %(29/48) in gastric carcinoma. The expression of COX-2 was correlated with TNM stage and lymph node metastasis (P<0.05). We also found that P-glycoprotein expression rate in COX-2 positive expression group was 82.8 %(24/29), and 63.2%(12/19) of P-glycoprotein was not expressed in COX-2 negative expression group. The over-expressions of COX-2 was significantly correlated with P-glycoprotein,  The correlation coefficient was r=0.470 (P<0.01).

Conclusions：COX-2 expression is involved in the carcinogenesis and malignant progression of gastric carcinoma, also COX-2 might take part in mediation of  multidrug-resistance (MDR) in gastric carcinoma through interference in the P-glycoprote in expressions.