中文摘要：

背景与目的在肺癌组织中，p120-catenin（p120ctn）与small GTP酶家族中的主要成员Rac1的表达是否具有相关性，至今尚不清楚。方法本研究应用S—P免疫组化、Western Blot、RT—PCR方法观察138例肺癌标本及2种具有不同侵袭转移能力的同源肺癌细胞系中p120ctn和Rac1的表达。结果在肺癌组织p120ctn的蛋白和mRNA表达水平均明显低于正常肺组织，而Rac1在肺癌组织中的表达明显高于正常肺组织，p120ctn的异常表达与Rac-1的过表达有较好的相关性（Correlation coefficient=0．720，P〈0．001），并与肺癌的分化（P=0．022），分期（P=0．010）和淋巴结转移（P=0．009）相关。同时，在肺癌细胞系中我们还观察到p120ctn表达下降和Rac1的过表达现象在具有高转移能力的BE1细胞系中尤为突出。结论肺癌中p120ctn的异常表达Rac1的过表达有关，并与肺癌的恶性程度相关。

英文摘要：

Background and objective To explore the correlation between p120-catenin （p120ctn） and small GTPases in human lung cancer, and their effect on the cell-cell adhesion, we examined the expression patterns of p120ctn and Rac1, whieh is the core member of small GTPases, and their correlation with elinieopathological factors. Methods S-P immunohistochemistry, Western Blot, and RT-PCR were used to deteet the expression patterns of p120ctn and Racl in 138 patients with non-small cell lung cancer （NSCLC） and two kinds of homologous lung cancer cell lines. We also used an in vitro model to evaluate their expression, and to determine whether protein expression correlated with the invasive capacity of lung cancer cell lines. Results In lung cancer, the levels of protein and mRNA expression of p120ctn were significantly lower than normal lung tissue, and Rac 1 was also found to be higher in tumor tissue than in normal lung tissue. A correlation between abnormal p120ctn and overexpression of Rael （Correlation coefficient=0.720, P〈0.001） was also associated with malignancy of lung cancer, such as poor differentiation （P=0.022）, high TNM stage （P=0.010）, and lymph node metastasis （P=0.009） in NSCLC patients. Abnormal expression of p120ctn anti overexpression of Racl was significantly associated with the high metastatic capacity of BE1 cells. Conclusion Abnormal p120ctn expression correlates with Rael overexpression, which contributes to the malignancy-related of NSCLC.