Development and Characterization of Novel SERMs

描述(申请人提供)：这项研究的目的是确定激素依赖组织和癌症中雌激素激动剂和拮抗剂之间的分子和结构差异，并鉴定、开发和表征具有期望的组织选择性雌激素或抗雌激素特性的新化合物。由于这些作用是由两种雌激素受体Era和ER(J)中的一种或两种介导的，因此了解受体-配体复合体的构象变化并分析新型受体配体的行为特征对于开发选择性雌激素受体调节剂(SERM)至关重要。因此，该项目的一个主要目标是将化合物在体外和体内的行为与ERA和ER(3)的晶体结构联系起来，以结合新的类固醇和非类固醇SERM。这些信息将被用来帮助修改或设计具有可预测的、改变的药理特性的化合物。为了实现这些目标，我们将：1)确定人类ERA和ER(5种蛋白质)的详细晶体结构，包括LBD和直到全长受体的额外功能结构域，并结合具有独特组织选择性和受体选择性特性的已知和新型SERM。辅助调节多肽和/或结晶伴侣(Fab和FN3单体)的加入将有助于结晶，以稳定ER复合体。结构导向突变将用于确定功能结构域内和功能结构域之间的重要联系。这些信息将被用来修饰和/或设计具有改变的药理性质的配体。2)在体外和激素敏感的动物肿瘤模型中，特别是SCID小鼠异种移植瘤和C3(1)/SV40T抗原转基因小鼠的自发性乳腺肿瘤模型中，鉴定新的ERA和/或ER0选择性配体。为了确定潜在的治疗效果，我们还将通过测量子宫营养反应、胆固醇水平和骨密度来研究候选配体在大鼠和小鼠身上的体内药理学。这一行为将与两种ER在转基因细胞中雌激素反应启动子的报告分析中的活性进行比较。ER亚型特异性相互作用的表征将有助于识别和/或创建对ERA和ER3起不同作用并具有新的治疗特性的新化合物。详细的结构信息也将有助于揭示这种行为的分子基础。预计从这项研究中衍生的化合物可能在治疗和/或预防激素敏感型癌症，特别是乳腺癌方面有应用，也可能作为激素替代疗法的试剂。

DESCRIPTION (provided by applicant): The objective of this investigation is to determine the molecular and structural distinctions between estrogen agonism and antagonism in hormone dependent tissues and cancers and to identify, develop and characterize novel compounds that have desired tissue-selective estrogenic or antiestrogenic properties. Because these effects are mediated by one or both of the two estrogen receptors, ERa and ER(J, knowledge of the induced conformational changes of receptor-ligand complexes and analysis of behavior profiles for novel receptor ligands is essential for developing selective estrogen receptor modulators (SERMs). Therefore, a major goal of this project is to correlate compound behavior in vitro and in vivo with the crystallographic structures of ERa and ER(3 bound to novel steroidal and nonsteroidal SERMs. This information will be used to help modify or design compounds with predictable, altered pharmacological properties. To accomplish these goals we will: 1) Determine the detailed crystallographic structures of the human ERa and ER(5 proteins, including the LBDs and additional functional domains up to full-length receptor, in combination with known and novel SERMs with unique tissue-selective and receptor-selective properties. Crystallizations will be assisted by the inclusion of coregulator peptides and/or crystallization chaperones (Fab and FN3 monobody) to stabilize ER complexes. Structure guided mutagenesis will be used to define important contacts within and between functional domains. This information will be used to modify and/or design ligands with altered pharmacological properties. 2) Characterize novel ERa and/or ER0- selective ligands in in vitro and in hormone-sensitive animal tumor models, especially SCID mouse xenografts and C3(1)/SV40 T-antigen transgenic mice that develop spontaneous mammary tumors. To determine potential therapeutic utility, we will also study the in vivo pharmacology of candidate ligands in rats and mice by measuring uterotrophic response, cholesterol levels, and bone density. This behavior will be compared with the activities of both ERs in reporter assays of estrogen responsive promoters in transfected cells. The characterization of ER subtype-specific interactions will facilitate the identification and/or creation of new compounds that act differently on ERa and ER3 and possess novel therapeutic properties. Detailed structure information will also help reveal the molecular basis for such behavior. It is anticipated that compounds derived from this study may have application in the treatment and/or prevention of hormone sensitive cancers, especially breast cancer, and may also have utility as agents for hormone replacement therapy.