维甲酸抑制雌激素受体阳性乳腺癌细胞生长机制的研究

目的探讨雌激素受体的表达对维甲酸抑制乳腺癌细胞生长的影响和ＲＡＲα表达的变化。方法雌激素受体阴性的乳腺癌细胞株ＭＤＡ－ＭＢ－２３１细胞,采用分子生物学质粒转染技术,将ＥＲ阴性的乳腺癌细胞ＭＤＡ－ＭＤ－２３１转染成ＥＲ阳性细胞。结果发现ＥＲ转染后的细胞不仅ＲＡＲα的基础表达升高,而且ＲＡ能明显抑制该细胞的生长。同时还发现,无论是已确立的雌激素受体阳性的乳腺癌细胞株,还是雌激素受体转染后的细胞,雌激素都能明显刺激ＲＡＲα的表达。结论雌激素通过ＥＲ上调ＲＡＲα量的表达,在维甲酸对乳腺癌细胞生长的抑制中起着很重要的作用。

Inhibition of estrogen receptor-positive human breast carcinoma cell growth by retinoic acid

OBJECTIVE: To evaluate whether the growth inhibition by retinoic acid and RAR alpha mRNA expression levels were affected by the change of ER expression. METHODS: The ER-negative breast cancer cell line MDA-MB-231 was transfected with the ER gene by stable transfection. RESULTS: In ER-transfected cells not only was the RAR alpha mRNA expression increased, but their growth was inhibited by retinoic acid as well. Estrogen could greatly stimulate the RAR alpha gene expression not only in established ER-positive cell lines but also in ER-transfected MDA-MB-231 cells. CONCLUSION: Our data strongly suggest that ER-mediated enhancement of RAR alpha levels play an important role in RA inhibition of human breast cancer cell growth.