肺癌细胞中p120-catenin的基因缺失促进肺癌细胞的侵袭和转移能力

p120 -catenin allele lack promotes cancer cells` ability of invasion and metastasis in lung cancer cell lines

目的探讨肺癌细胞中p120-catenin(p120ctn)在非小细胞肺癌侵袭、转移中的作用及其可能的机制。方法应用siRNA方法干扰肺癌细胞系BE1,SPC,LTE中p120ctn的表达后,应用Westernblot及RT-PCR方法检测E-cadherin、β-catenin蛋白及mRNA表达情况的变化;应用流式细胞术及Transwell实验检测肺癌细胞增殖、侵袭和转移能力变化;应用Pull-down方法检测小GTP酶活性的变化;应用体内侵袭实验检测肿瘤形成情况。结果 p120ctn表达下调明显地减弱E-cadherin和β-catenin的蛋白表达,同时,还可以下调β-catenin的mRNA表达。p120ctn表达下调还能使Cdc42和Rac1活性增高,RhoA的活性降低,并且促进肺癌细胞的增殖、侵袭和转移。将稳定转染了p120siRNA和转染空质粒的细胞克隆分别移植至裸鼠皮下,发现整合了p120siRNA的荷瘤鼠的肿瘤生长迅速,侵袭和转移能力增强。结论 p120-catenin的缺失可促进肺癌细胞的侵袭和转移能力,其机制可能通过下调E-cadherin和β-catenin的表达从而降低细胞间粘附,以及激活Cdc42/Rac1、失活RhoA来实现。

Objective To investigate the role of p l20-catenin （pl20ctn） on the invasion and metastasis of lung cancer. Methods We have created several cell colons from cell lines such as BE1, SPC and LTE with siRNA p120catenin interference. The abilities of the lung cancer cells to invade through reconstituted matrigel in transwell chambers were investigated in vitro and the invasion effect in vivo was determined using the xenograft models of lung cancer cells in nude mice. Western blot and RT-PCR methods were used to determine the expression of E-cadherin and β -catenin; Pulldown assay was used to determine the activity of small GTPase. Results Ablation of p120etn reduced the levels of E- cadherin and β -catenin, as well as the mRNA of β -catenin. Further, p120ctn ablation inactivated RhoA, but increased the activity of Cdc42 and Racl, and promoted proliferation and the invasive ability of lung cancer cells both in vitro and in vivo. Conclusions In lung cancer, p120ctn loss reduced the levels of E-cadherin and β -catenin, inactivated RhoA, but increased the activity of Cdc42 and Rac 1, and promoted proliferation and the invasive ability of cancer cells.