目的

研究在不同处理因子作用下,外源基因ERβ1 的表达对MCF-7 乳腺癌细胞系生长特性的影响。

方法

利用脂质体转染方法将ERβ1 真核表达载体pcDNA3.1- EGFPERβ1 导入MCF-7 乳腺癌细胞系。 采用Western blot 方法检测转染细胞中ERβ1 的蛋白表达水平,筛选阳性克隆。 以亲本细胞MCF-7 为对照,分别在雌激素和雌激素受体拮抗剂他莫昔芬作用下观察细胞的生长特点。

结果

在转染ERβ1 基因的MCF-7 细胞系中,Western blot 检测证实ERβ1 的蛋白表达水平显著增高。 在无处理因子的情况下,外源基因ERβ1 在MCF-7 细胞系中的表达能抑制细胞生长。 与亲本细胞MCF-7 细胞相比,转染ERβ1 的MCF-7 细胞对雌激素的敏感性下降,但对他莫昔芬的敏感性无明显变化。

结论

外源性ERβ1 基因在MCF-7 乳腺癌细胞中的稳定表达不增加对他莫昔芬的耐药性,但使之对雌激素的敏感性下降。

Objective

To study the effects of exogenous ERβ1 on the growth of breast cancer MCF-7 cells under different treatment with estrogen or tamoxifen.

Methods

An eukaryotic expression vector containing human entire coding sequence of ERβ (pcDNA3.1-l EGFPERβ1) was transfected into human breast cancer MCF-7 cells using lipofectin reagent. The biological activity of ERβ1was detected with the expression of ERβ1 protein by Western blot. The growth properties of MCF-7, transfected MCF-7 cells under different treatment, including E2 (17beta-lestradiol) and tamoxifen, were observed.

Results

Western blot analysis showed that the protein level of ERβ1 in the transfected MCF-7 cells was markedly increased.Exogenous ERβ1 expression inhibit the growth properties of MCF-7 cells under normal condition. The transfected MCF-7 cells proliferated at the same rate as naive cells in the presence of tamoxifen, whereas a strong inhibition of the proliferation of the transfected MCF-7 cells in the presence of E2 was observed.

Conclusions

Exogenous ERβ1 expression does not increase the resistance to tamoxifen, and a strong inhibition of the proliferation may occurre in the presence of E2.