中文摘要：

目的：探讨埃兹蛋白（Ezrin）对人高、低转移潜能乳腺癌细胞亚系细胞增殖和侵袭能力的影响。方泼：采用乳腺癌细胞系MDA—MB-435s，利用细胞穿透人工基底膜能力的差异筛选出具有高、低转移潜能的乳腺癌细胞系，采用免疫组织化学法、RT—PCR、Western印迹法和放射免疫显像（radioimmunoimaging，RII）方法检测Ezrin蛋白在高、低转移潜能乳腺癌细胞中的表达情况。采用MTT法检测细胞增殖能力及黏附率。结果：经人工基底膜成功分离出具有高、低转移潜能的MDA．MB-435s细胞。高转移潜能MDA-MB-435s细胞中Ezrin在基因和蛋白水平的表达均显著高于低转移潜能的MDA．MB-435s细胞，差异有统计学意义（P值均〈0．001）；高转移潜能MDA—MB-435s细胞的增殖能力和黏附率均高于低转移潜能的MDA—MB-435s细胞，差异有统计学意义（P值均〈0．001）；131I标记的抗Ezrin抗体在接种高转移潜能MDA—MB-435s细胞的裸鼠肿瘤部位的放射性浓聚要强于接种低转移潜能MDA．MB-435s细胞的裸鼠肿瘤部位，差异有统计学意义（P〈0．001）。结论：Ezrin在高转移潜能乳腺癌细胞中的表达水平明显高于低转移潜能细胞，2者的增殖、黏附和侵袭力都有明显差异，上述结果为Ezrin用于乳腺癌的诊断和治疗提供了理论依据。

英文摘要：

Objective ： The purpose of this experiment was to study the effect of Ezrin protein on cell proliferation and invasion in the two subgroups of human breast cancer ceils with high and low metastatic potentialities, respectively. Methods：Two subgroups of hu- man breast cancer cells with high and low metastatic potentialities were selected from MDA-MB-435s ceils by testing their capability passing artificial basement membrane. The expression levels of Ezrin mRNA and protein were determined by immunohistochemical method, RT-PCR, Western blot, and radioimmunoimaging method, respectively. The proliferation ability and adhesion rate of the ceils were examined by MTr assay. Results：This study successfully isolated two subgroups of MDA-MB435 s cells with high or low metastatic potentialities by using an artificial basement membrane. The expression of Ezrin at mRNA and protein levels were significantly higher in highly metastatic MDA-MB435s cells than that in lowly metastatic MDA-MB435s cells. The difference was significant （P 〈 0. 001 ）. The proliferation ability and adhesion rate were also higher in highly metastatic MDA-MB435s cells than those in lowly metastatic MDA- MB435s cells. The difference was significant （ P 〈 0.001 ）. The radioactivity of 131I labeled Ezrin antibody in xenografted tumor body in nude mice was significantly stronger in highly metastatic cells than that in lowly metastatic MDA-MB-435s cells. The difference was significant （P 〈 0. 001 ）. Conclusion：The expression of Ezrin was significantly higher in cells with high metastatic potentialities. The over-expression of Ezrin induced the significant difference in cell proliferation, adhesion, and invasion between two subgroups of MDA- MB-435s cells. The results provided a theoretical basis for using Ezrin protein in the diagnosis and treatment of breast cancer.