癌基因CTTN编码蛋白Cortactin与大肠癌细胞内吞作用的关系  

A pivotal role of cortactin, a CTTN encoding protein, in endocytosis of human colon cancer

作　　者：朱建伟[1] 马利林[1] 黄宝玉[1] 刘培根[1] 汝凯[1] 曹翔[1] 钱飞[1] 

机构地区：[1]南通大学附属医院胃肠外科,南通226001

出　　处：《中华医学杂志》2011年第6期385-390,共6页National Medical Journal of China

基　　金：国家自然科学基金（30771126）;教育部留学回国人员基金;江苏省自然科学基金（BK2006058）

摘　　要：目的分析Cortactin分子与大肠癌细胞内吞作用的关系，了解癌组织高表达Cortactin的内在意义。方法采用免疫组化和蛋白印迹检测大肠癌组织、癌旁组织及大肠癌细胞系中Cortactin表达水平；采用小干扰RNA抑制癌细胞Cortactin表达，并构建Cortactin不同功能区缺失突变体，检测各种癌细胞Tfn内吞作用的变化；采用免疫荧光化学方法分析Cortactin与癌细胞内吞作用路径的关系。结果大肠癌组织Cortactin表达高于癌旁组织，表达率分别为77．5％及47．5％（P〈0．05）。siRNA处理的癌细胞Tfn摄取值为0．61±0．02，对照为1．01±0．16（P〈0．05）。高表达Cortactin的大肠癌细胞为实现正常的内吞作用，需要足够数量和结构完整的Cortactin蛋白；Cortactin参与内吞物质的胞内运输过程。结论大肠癌细胞的内吞作用依赖Cortactin分子功能的发挥，高表达Cortactin有利于大肠癌细胞基于内吞作用的信号传导、侵袭和转移。Objective To explore the role of cortactin in endocytosis of colon cancer cells and clarify the significance of its over-expression in colon cancer tissues. Methods Immunohistochemistry and Western blot were employed to detect the expression of cortactin in benign and malignant tissues and cells. Cell endocytosis was examined in cancer cells after siRNA treatment and DNA transfection with plasmid encoding cortactin wild type and domain deletion mutants. Results Cortactin was over-expressed in colon cancer tissues than in adjacent normal tissues. The expression rate was 77.5% in cancer tissues and 47.5% in normal tissues （ P 〈 0. 05 ）. The value of transferrin uptake was 0. 61 ±0. 02 in siRNA treated cancer cells and 1.01 ±0. 16 in the control cells （ P 〈 0. 05 ）. Intact molecule and sufficient level of cortactin was required for an optimal endocytosis of cancer cells. Cortactin was involved in coated-vesicle transportation in cells. Conclusion Endocytosis in colon cancer ceils is dependent on an intact expression of CTI＇N. An over-expression of cortactin facilitates the signaling in invasion and metastasis related to endocytosis.

关 键 词：结肠肿瘤 皮质蛋白 内吞作用 

分 类 号：R735.34[医药卫生—肿瘤]