中文摘要：

目的探讨雌激素受体β1（estrogen receptor β1，ERβ1）能否通过调控E-钙粘蛋白（E-cadherin，E-cad）的表达影响乳腺癌细胞上皮间质转化（epithelial-mesenchymal transition，EMT）的发生，ERβ1在乳腺癌细胞侵袭迁移中的作用。方法通过脂质体法将ERβ1真核表达质粒和特异性siRNA-ERβ1转染至人乳腺癌MDA-MB-231细胞中，干预细胞中ERβ1的表达，采用RT-PCR、Western blot法分别在mRNA和蛋白水平观察干预ERβ1后对E-cad表达的影响，进行体外侵袭迁移实验，观察干预细胞中ERβ1的表达对乳腺癌细胞恶性生物学行为的改变。结果过表达ERβ1后，ERβ1及E-cad在mRNA[（0.823±0.028） vs （0.554±0.044）,P=0.025;（0.944±0.04） vs （0.724±0.28）,P=0.026]和蛋白[（1.331±0.019） vs （0.463±0.019）, P=0.001;（1.428±0.005） vs （0.500±0.010）, P〈0.01]水平均表达升高，侵袭[（45.8±7.4） vs （70.4±13.3）, P=0.039]迁移[（75.6±8.8） vs （111.8±15.1）, P=0.021]力显著下降，干扰ERβ1表达后，ERβ1及E-cad在mRNA[（0.314±0.029） vs （0.554±0.044）,P=0.030;（0.444±0.042） vs （0.724±0.28）,P=0.001]和蛋白[（0.353±0.017） vs （0.463±0.019）, P=0.032;（0.397±0.034） vs （0.500±0.010）, P=0.024]水平均表达降低，侵袭[（193±22.6） vs （70.4±13.3）, P〈0.05]迁移[（264.2±53.7） vs （111.8±15.1）, P=0.002]力显著增强。结论ERβ1可能参与乳腺癌的EMT过程，进而影响乳腺癌细胞的侵袭转移能力。

英文摘要：

Objective To investigate the role of estrogen receptor β1 （ERβ1） in epithelial-mesenchymal transition （EMT） of breast cancer cells by regulating the expression of E-cadherin （E-cad）, and to explore the effects of ERβ1 on the invasion and migration of breast cancer cells.Methods The recombinant eukaryotic vector containing ERβ1 cDNA or specific siRNA targeting ERβ1 was transfected to human breast cancer cells MDA-MB-231 to interfere the expression of ERβ1. RT-PCR and Western blotting were used to detect the expression of ERβ1 and E-cad on mRNA and protein levels. Moreover, invasion and migration assays in vitro were applied to assess the influence of ERβ1 expression interference on malignant biological behavior of breast cancer.Results When ERβ1 was over-expressed, ERβ1 and E-cad showed increased expression at mRNA （0.823±0.028 vs 0.554±0.044, P=0.025; 0.944±0.04 vs 0.724±0.28, P=0.026） and protein （1.331±0.019 vs 0.463±0.019, P=0.001; 1.428±0.005 vs 0.500±0.010, P〈0.01） levels, and the cells showed decrease of invasion （45.8±7.4 vs 70.4±13.3, P=0.039） and migration （75.6±8.8 vs 111.8±15.1, P=0.021） abilities. When ERβ1 was down-regulated, ERβ1 and E-cad showed decreased expression at mRNA （0.314±0.029 vs 0.554±0.044, P=0.030; 0.444±0.042 vs 0.724±0.28, P=0.001） and protein （0.353±0.017 vs 0.463±0.019, P=0.032; 0.397±0.034 vs 0.500±0.010, P=0.024） levels, and the cells showed increase of invasion （193±22.6 vs 70.4±13.3, P〈0.05） and migration （264.2±53.7 vs 111.8±15.1, P=0.002） abilities.Conclusion ERβ1 may participate in EMT of breast cancer and further influence the invasion and metastasis of breast cancer.