E—cadherin和β-catenin在胸腺瘤侵袭转移过程中的表达及意义

The expression and significance of E- cadherin and β- catenin in the invasion and metastasis of thymoma

目的探讨E—cadherin和β—catenin在胸腺瘤侵袭转移过程中的表达及意义。方法应用β—catenin与E—cadherin单克隆抗体对87例胸腺上皮性肿瘤组织石蜡切片标本进行免疫组化PV6000检测，并观察两者的表达与胸腺瘤侵袭和转移之间的关系。结果E—cadherin在WHO分型为A、AB、B1、B2、B3、C型胸腺瘤中的阳性率分别为44．4％、37．5％、41．2％、47．1％、58．3％和31．3％，差异无统计学意义（χ^2=2．394，P〉0．05）；在Masaoka系统Ⅰ、Ⅱ、Ⅲ-Ⅳ期胸腺瘤中的阳性率随肿瘤分期增高而降低，分别为60．0％、19．2％和18．2％，差异具有统计学意义（χ^2=15．469，P〈0．05）。B—catenin在A、AB、B1、B2、B3、C型胸腺瘤中的阳性率分别为33．3％、25．0％、29．4％、23．5％、33．3％和37．5％，差异无统计学意义（χ^2=1．074，P〉0．05）；在Ⅰ、Ⅱ、Ⅲ-Ⅳ期胸腺瘤中的阳性率随着肿瘤分期增高而增高，分别为12．0％、38．5％和90．9％，差异具有统计学意义（χ^2=24．625，P〈0．05）。结论E—cadherin和B—catenin异常表达参与细胞的恶性转化，与胸腺癌的生长类型、侵袭转移密切相关，是判断胸腺癌生物学行为的良好指标。

Objective To investigate the expression and significance of E - cadherin and β - catenin in the invasion and metastasis of thymoma. Methods The expression of β - catenin and E - cadherin in the paraffin sections of 87 cases of thymic epithelial tumor tissue was examined by immunohistochemistry. Then, the relationship between the expression of β - catenin and E - cadherin and the invasion and metastasis of thymoma was observed. Results According to WHO classification, the positive expression of E - cadherin was 44.4% , 37.5% , 41.2% , 47.1% , 58.3% and 31.3% in Types A, AB, B1, B2, B3 and C of epithelial thymoma, respectively, without statistical difference （ χ^2 = 2. 394, P 〉 0.05 ）. In the Masaoka system, the positive expression rate of E -cadherin was 60% , 19.2% and 18.2% in Stages Ⅰ , Ⅱ and Ⅲ- Ⅳ of epithelial thymoma, which was decreased along the increase of tumor stage, with statistical difference between the two groups （ χ^2 = 15. 469, P 〈 0.05 ）. According to WHO classification, the positive expression of β - catenin was 33.3% , 25.0%, 29.4%, 23.5% , 33.3% and 37.5% in Types A, AB, B1, B2, B3 and C of epithelial thymoma, respectively, without statistical difference （χ^2= 1. 074, P 〉 0. 05）. In the Masaoka system, the positive expression rate of β - catenin was 12.0% , 38.5% and 90.9% in Stages Ⅰ , Ⅱ and Ⅲ- Ⅳ of epithelial thymoma, which was increased along the increase of tumor stage, with statistical difference between the two groups （χ^2 = 24.625, P 〈 0.05 ）. Conclusions E- cadherin and β -catenin with abnormal expression are involved with malignant cell transformation, and related to the type, invasion and metastasis of thymoma, which act as good indicators of thymoma biological behavior.