Mechanisms of estrogen receptor ligand signaling

雌激素受体-(ER)是最成功的分子实体之一，既是一种生物标志物，也是一种靶标。 癌症治疗，但约30-50%的患者表现出从头开始或获得性耐药。ER是一种配体调控的转录 组蛋白修饰酶调控ER+乳腺癌基因表达和生长的因子 (BCS)。重要的是，不同的SERM、SERDS和芳香酶抑制剂的治疗方式会导致不同的 对内质网的构象效应，通常允许对一种治疗类型的耐药性被另一种治疗方法有效地治疗。那里 目前对新疗法和获得性耐药模型有效的新疗法的重大临床需求尚未得到满足， 如受体酪氨酸激酶的过度表达或其下游信号通路的激活。我们最近 研究表明，EGFR过表达模型使乳腺癌细胞对SERM产生广泛耐药，如在患者中所见。 我们还开发了一种新的内质网化学靶向策略，我们称之为双机制内质网抑制剂(DMERI)。 重要的是，我们发现SERM和SERD DMERI在EGFR过表达模型中都是有效的，并且许多 在福维斯特耐药模型中，它们显示出比福维斯特更好的疗效。SERM DMERI可能是一种有效的 首发时EGFR过度表达的患者的治疗，包括ER+BCS的一个重要亚群 与临床耐药有关。SERM和SERM DMERI在抗药效果上的显著差异 模型为我们提供了强大的化学生物学工具来剖析作用机制。我们的第一个目标是了解 ER/EGFR信号串扰的机制及不同类型ER配体的调节第二个目标是 通过识别配体特异性的辅助调节因子，更全面地了解配体作用的分子机制。 调节ER依赖的生长抑制的基因网络。配体-受体-辅调节基因密码子的描述 将有助于理解配体的作用机制和转录调控在细胞控制中的基本原理 成长。

The estrogen receptor- (ER) represents one of the most successful molecular entities as both a biomarker and target for cancer therapy, but some 30-50% of patients show de novo or acquired resistance. ER is a ligand regulated transcription factor that acts as a scaffold for histone modifying enzymes to modulate gene expression and growth of ER+ breast cancers (BCs). Importantly, the different treatment modalities of SERMs, SERDs and aromatase inhibitors induce different conformational effects on ER that often allow resistance to one type of treatment to be effectively treated by another. There is currently a significant unmet clinical need for new therapies that are effective in de novo and acquired resistance models, such as overexpression of receptor tyrosine kinases or activation of their downstream signaling pathways. We recently showed that an EGFR overexpression model rendered breast cancer cells broadly resistant to SERMs, as seen in patients. We also developed a new chemical targeting strategy for ER, which we call dual mechanism ER inhibitors (DMERI). Importantly, we identified both SERM and SERD DMERI as efficacious in the EGFR overexpression model, and many of them showed efficacy greater than fulvestrant, and in fulvestrant resistance models. The SERM DMERI may be an effective treatment for patients with EGFR overexpression at initial presentation, comprising a significant subset of ER+ BCs associated with clinical resistance. The marked difference in efficacy between SERMs and SERM DMERI in this resistant model provide us with robust chemical biology tools to dissect mechanisms of action. Our first goal is to understand the mechanisms of ER/EGFR signaling crosstalk and its regulation by different classes of ER ligands. A second goal is to understand the molecular mechanisms of ligand efficacy more generally through identifying ligand-specific coregulator- gene networks that regulate ER-dependent growth inhibition. The delineation of the ligand-receptor-coregulator gene code will enable understanding ligand mechanism of action and basic principles of transcription regulation in control of cell growth.