雌激素受体β过表达对大肠癌细胞侵袭的影响

Effect of estrogen receptor beta gene over-expression on the invasion of colorectal cancer cells

目的:观察雌激素受体β(ERβ)过表达对侵袭转移相关基因E-钙黏蛋白和CXCR4表达的影响,研究其对大肠癌细胞侵袭能力的影响。方法:以脂质体介导的ERβ基因转染SW480细胞,G418筛选阳性克隆(SW480-C1-ERβ)。以正常SW480细胞和转染了空质粒的SW480细胞(SW480-pEGFP-C1)作为对照,在有或无雌激素作用的条件下,利用Transwell小室法测定SW480、SW480-pEGFP-C1和SW480-C1-ERβ细胞的侵袭能力;采用Western blot法检测各组细胞中E-钙黏蛋白和CXCR4蛋白的表达。结果:在无雌激素作用时,SW480-C1-ERβ细胞的侵袭能力和CXCR4的表达显著低于另两株细胞(P<0.05)。有雌激素作用时,SW480-C1-ERβ细胞在三者中的侵袭能力最低,E-钙黏蛋白的表达最高(P<0.05),而CXCR4表达无明显变化。在SW480-C1-ERβ组细胞中,雌激素作用时肿瘤细胞的侵袭能力和E-钙黏蛋白的表达分别明显低于和高于无雌激素作用时的细胞(P<0.05),而CXCR4的表达无明显差异。结论:ERβ可以以配体非依赖性的方式和配体依赖性的方式抑制大肠癌细胞的侵袭转移,这种效应可能与调控E-钙黏蛋白和CXCR4的表达有关。

Objective To observe the effect of estrogen receptor beta （ERβ） gene over-expression on expressions of the invasive and metastasis-related gone E-cadherin and CXCR4, and to study the effect on the invasion of colorectal cancer cells . Methods The ERβ gene was transfected into SW480 cells via lipofectamine 2000. The positive clone ceils of SW480-C1- ERβ were selected by G418. Normal SW480 cells and empty plasmid- transfected SW480 cells （SW480-pEGFP-C1） were set as control. With or without estrogen, the invasion ability of SW480 cells, SW480-pEGFP-C1 cells and SW480-C1-ERβ cells were measured by transwell chamber assay. E-cadherin and CXCR4 expression of these groups was tested by Western Blot. Results Without estrogen, the invasion ability and CXCR4 expression of SW480-C 1-ERβ group were significantly lower than the other two groups （P 〈 0.05）. With the action of estrogen, the invasion ability of the SW480-C1-ERβ group is the lowest,and the E- cadherin expression of SW480-C1-ERβ group is the highest among three groups.But the expression of CXCR4 did not significantly change. For SW480-C1-ERβ group, the invasion of estrogen-treated cells were significantly lower and and the E-cadherin expression were significantly higher than the non-estrogen-treated SW480-C1-ERβ group （P 〈 0.05） ; while CXCR4 expression did not significantly change. Conclusion Over-expression of ERβ can inhibit the invasion ability of colon cells both in ligand-independent and ligand-dependent manner, and these effects may beassociated with modulation the expressions of E-cadherin and CXCR4.