胃癌中E-cadherin、MMP-2的表达及侵袭转移机制

Expression of E-cadherin and MMP-2 in gastric carcinoma and its mechanism of invasion and metastasis

目的通过检测E-cadherin和MMP-2蛋白在胃癌中的表达,探讨它们在肿瘤转移和侵袭过程中的作用。方法取胃癌组织50例,正常胃黏膜10例;应用SP法免疫组化检测E-cadherin、MMP-2蛋白的表达。结果 (1)胃癌组织中E-cadherin蛋白的阳性表达率为46%(23/50),明显低于正常黏膜100%(10/10,P<0.001)。转移组阳性表达率为35.29%(12/34)明显低于非转移组68.75%(11/16),差异有显著性(P<0.05)。与临床分期、浸润分级的关系显示,Ⅲ-Ⅳ期和T3-T4级癌组织中E-cadherin蛋白表达分别明显低于Ⅰ-Ⅱ期和T1-T2级(P<0.05)。E-cadherin表达还与组织学分级相关:胃癌分化程度低则阳性表达率也低;分化程度高则阳性表达率也高,差异有显著性(P<0.05)。(2)MMP-2在胃癌组织中阳性表达率为74%(37/50),而正常胃黏膜上皮细胞中几乎无棕染颗粒,其差异有显著性(P<0.05)。转移组MMP-2阳性表达率(82.35%)明显高于非转移组(56.25%,P<0.05)。MMP-2的表达与组织学分级明显相关:随着胃癌分化程度降低,MMP-2阳性表达率升高(P<0.05);Ⅲ-Ⅳ期胃癌表达明显高于Ⅰ-Ⅱ期(P<0.05);T3-T4级MMP-2阳性表达率高于T1-T2级(P<0.001)。(3)MMP-2与E-cadherin表达之间呈高度负相关(相关系数r=-0.368,P<0.009)。结论 MMP-2在胃癌中均呈高表达,而E-cadherin则反之。E-cadherin蛋白表达减弱与胃癌侵袭转移潜能相关,可作为胃癌侵袭转移的生物学标志之一。

Purpose To investigate the expression of E-cadherin and MMP-2 in gastric carcinoma and to explore the role of E-cadherin and MMP-2 in the metastasis and invasion of gastric carcinoma. Methods 50 cases of gastric carcinoma were analyzed, meanwhile 10 normal gastric mucosa samples were studied as controls. SP method was used to detect the expression of E-cadherin and MMP-2 in all the cases. Results E-eadherin expression in gastric carcinoma （46%） was significantly lower-than that in normal gastric mucosa （100%） （P 〈0. 01 ）. The positive rate of E-cadherin in non-metastatic group （68.75%） was higher than that in metastatic group （35.29%） （P 〈 0. 05 ）. The expression of E-cadherin in stages Ⅰ -Ⅱ and T1-T2 was significantly higher than those in stages Ⅲ-Ⅳand T3-T4 （P 〈0. 05, respectively）. And also the significant correlation was observed between E-cadherin expression and histological grade （ P 〈 0.05 ）. The positive rate of E-cadherin in poorly differentiated group was significantly lower than that in well differentiated group. No relationship was observed among E-cadherin expression and sex, age, and metastasis （ P 〉 0.05 ）. The positive rate of MMP-2 protein in gastric carcinoma was 74% , whereas hardly found in normal gastric mucosa. There was significant difference between them （P 〈 0. 05 ）. The high expression of MMP-2 was related to tumor metastasis （P 〈 0. 05 ）. There was a significant correlation between high MMP-2 expression and degree of differentiation （ P 〈 0. 05 ）. The positive rates of MMP-2 in stages Ⅰ -Ⅱ were significantly lower than that in stages m-IV （P 〈 0. 05）. MMP-2 expression in T3-T4 was higher than that in T1 -T2 （ P 〈 0.01 ）. The expression of E-cadherin was reversely correlated with MMP-2 （ r = - 0. 368, P 〈 0. 01 ）. Conclusion The over-expression of MMP-2 and low-expression of E-cadherin are detected in gastric carcinoma. The lower expression of E-cadherin is possibly related to metastasis and invasion of carcinoma, and E-cadherin may be a useful marker for determining the biological aggressiveness of gastric carcinoma.