C3G/Rap1和Dock180/Rac1信号通路在卵巢癌浸润中的作用

Role of C3G/Rap1 and Dock180/Rac1 signal pathway in infiltration of ovarian cancer

目的探讨鸟嘌呤核苷酸交换因子C3G/Rap1酶和鸟嘌呤核苷酸交换因子Dock180/Rac1酶信号通路在卵巢癌浸润中的可能作用。方法 Western blot检测Dock180沉默的卵巢癌细胞SKOV3中C3G的表达,验证上皮性卵巢癌组织中Dock180与C3G的表达相关性;免疫组化比较卵巢癌组织中Dock180与C3G的表达趋势;免疫荧光观察SKOV3中Dock180与C3G及它们各自的下游蛋白Rac1/Rap1的定位。结果 Dock180基因沉默的细胞中C3G表达明显增强(P<0.05);Dock180与C3G在卵巢癌组织中的表达呈现相反趋势(P<0.05);C3G/Dock180均主要分布于细胞质,下游效应蛋白Rap1/Rac1在细胞膜和细胞质都有表达,但Rap1以细胞质为主,而Rac1可以伸展至细胞膜及细胞膜皱褶。结论卵巢癌细胞和组织中C3G与Dock180表达呈相反趋势,下游蛋白Rap1与Rac1在细胞内的定位分布差异,可能与C3G/Rap1和Dock180/Rac1信号通路在卵巢肿瘤浸润中的不同作用有关。

Objective To study the potential role of C3G/ Rap1 and Dock180/Rac1 signal pathway in infiltration of ovarian cancer.Methods Expressions of C3G in Dock180-silenced ovarian cancer SKOV3 cells were detected by Western blotting.Expressions of C3G and Dock180 in ovarian cancer tissue were compared by immunohistochemical analysis.The locations of D180/C3G and their downstream Rac1/Rap1 proteins were demonstrated in ovarian cancer cell SKOV3 by means of immunofluorescence staining.Results The expression level of C3G was significantly higher in Dock180-silenced SKOV3 cells than in wild type,blank plasmid transfected,and negative plasmid transfected cells（P〈0.05）.The expression of C3G in ovarian cancer tissue was inversely related with that of Dock180（P〈0.05）.Both C3G and Dock180 were mainly distributed in the cytoplasm.The downstream Rap1 and Rac1 proteins were expressed both in the cytomembrane and in the cytoplasm.However,Rap1 was mainly expressed in the cytoplasm while Rac1 was mainly expressed in the cytomembrane and its folds.Conclusion The expression of C3G in ovarian cancer cells and tissue is inversely related with that of Dock180.The Rap1 and Rac1 are differently distributed in ovarian cancer cells,which may be related with the different roles of C3G/Rap1 and Dock180/Rac1 signal pathway in the infiltration of ovarian cancer.