δ-catenin与Cdc42在非小细胞肺癌中表达的相关性

Correlation between δ-catenin and Cdc42 expression in non-small cell lung cancer

背景与目的:δ-catenin是p120 catenin亚家族中的成员,可与细胞膜上的E-cadherin直接结合,形成E-cadherin/catenin复合体。δ-catenin还可以通过调节Cdc42(Small GTP酶)活性以影响细胞骨架装配。该研究检测非小细胞肺癌(non-small cell lung cancer,NSCLC)中δ-catenin及Cdc42的表达情况并探讨了二者表达的相关性。方法:采用免疫组织化学方法检测122例NSCLC标本中δ-catenin与Cdc42的表达。采用蛋白[质]印迹法(Western blot)及逆转录聚合酶链反应(reverse transcription polymerase chain reaction,RT-PCR)法检测肺癌组织中δ-catenin及Cdc42的蛋白及m RNA表达情况。在肺癌细胞系中,分别上调或干扰δ-catenin的表达后,利用G-LISA及Transwell小室法检测Cdc42活性以及肺癌细胞侵袭能力的改变。结果:δ-catenin和Cdc42在肺癌组织中其蛋白及m RNA表达明显高于正常肺组织。而在122例NSCLC病例中,δ-catenin阳性表达率为65.57%(80/122),Cdc42过表达率为68.03%(83/122)。δ-catenin阳性表达和Cdc42的过表达具有较好的相关性(P<0.001)。δ-catenin和Cdc42的协同表达与肺癌的高临床分期、低分化、病理类型为腺癌和淋巴结转移相关(P<0.05),并且与肺癌患者的不良预后明显相关。在肺癌细胞系中通过调节δ-catenin表达,改变Cdc42的表达及活性,影响肺癌细胞的侵袭能力。结论:在肺癌组织中δ-catenin和Cdc42的表达具有相关性,而二者协同表达与患者不良预后相关。

Background and purpose： δ-catenin is a member of the p120 catenin subfamily, which can directly bind to E-cadherin on the cell membrane, forming E-cadherin/catenin complex. δ-catenin can also affect the cytoskeleton assembly by regulating the activity of Cdc42 （Small GTPase）. Therefore, this study detected the expression of δ-catenin and Cdc42 in non-small cell lung cancer （NSCLC） and investigated the relationship between them. Methods： The expressions of δ-catenin and Cdc42 in 122 cases of NSCLC were detected by immunohistochem- istry. This study also used Western blot and real-time fluorescent quantitative polymerase chain reaction （RTFQ-PCR） to detect the protein and mRNA expressions of δ-catenin and Cdc42 in lung cancer tissues. After up-regulating or downregulating δ-catenin in lung cancer cell line, the activity of Cdc42 and invasion ability of lung cancer cells were detected by G-LISA and Transwell. Results： The mRNA and protein expression of δ-catenin and Cdc42 in lung cancer tissues was significantly higher than that in normal lung tissues. In 122 NSCLC cases, the δ-catenin positive expression rate was 65.57% （80/122）, and the Cdc42 overexpression rate was 68.03% （83/122）. There was a good correlation between δ-catenin positive expression and Cdc42 overexpression （P〈0.001）. The co-expression of δ-catenin and Cdc42 was related to the high clinical stage, poor differentiation, adenocarcinoma and lymph node metastasis of lung cancer （P〈0.05）, and was significantly associated with poor prognosis in patients with lung cancer. In the lung cancer cell line, the expression and the activity of Cdc42 were changed by regulating the δ-catenin expression, which affected invasion ability of the lung cancer cells. Conclusion： The δ-catenin expression was significantly correlated with the Cdc42 expression. The co-expression of δ-catenin and Cdc42 in lung cancer was correlated with the poor prognosis of lung cancer.