Increasing evidence supports the anti-estrogenic and/or anti-proliferative properties of luteolin, which is a natural flavonoid existing in herbs, vegetables and fruits. However, the molecular mechanisms responsible for these effects are only partially explored. In the present study, estrogen receptor-alpha (ER-α) was identified as a potential molecular target for luteolin. Our data indicated that treatment with luteolin engendered suppression of ER-α protein and mRNA expression in ER-α-positive breast cancer cells. Y-box binding protein-1 (YB-1) is a known transcriptional regulator of ER-α expression. In this studies it was demonstrated that luteolin decreased YB-1 protein and mRNA expression. Integrin-linked kinase (ILK) is able to phosphorylate many downstream effectors that have the potential to regulate YB-1 transcription. We provided evidence for a mechanism by which luteolin suppressed YB-1 expression through the downregulation of ILK/Akt/STAT3-regulated Twist expression in ER-α-positive breast cancer cells. Our data also showed that luteolin inhibited cancer migration and invasion through the inhibition of epithelial-mesenchymal transition (EMT). Taken together, these data indicate that the antitumorigenic effects of luteolin in ER-α-positive breast cancer cells may arise from its ability to reduce ER-α expression.

越来越多的证据支持木犀草素的抗雌激素和/或抗增殖特性，木犀草素是存在于草药，蔬菜和水果中的天然类黄酮。但是，仅部分探讨了导致这些作用的分子机制。在本研究中，雌激素受体-α（ER-α）被确定为木犀草素的潜在分子靶标。我们的数据表明，用木犀草素治疗可抑制ER-α阳性乳腺癌细胞中的ER-α蛋白和mRNA表达。Y-box结合蛋白1（YB-1）是ER-α表达的已知转录调节因子。在这项研究中，证明了木犀草素降低了YB-1蛋白和mRNA表达。整联蛋白连接的激酶（ILK）能够磷酸化许多下游调节子，这些调节子可能具有调节YB-1转录的潜能。我们提供了有关木犀草素通过下调ER-α阳性乳腺癌细胞中ILK / Akt / STAT3调节的Twist表达来抑制YB-1表达的机制的证据。我们的数据还表明，木犀草素通过抑制上皮-间质转化（EMT）来抑制癌症的迁移和侵袭。综上所述，这些数据表明木犀草素在ER-α阳性乳腺癌细胞中的抗肿瘤作用可能来自其降低ER-α表达的能力。