Inhibitors of Tyrosine Kinase-Dependent Signalling as An

酪氨酸激酶依赖性信号传导抑制剂

• 批准号: 7290820
• 负责人: TERRENCE BURKE
• 金额: --
• 依托单位: DIVISION OF BASIC SCIENCES - NCI
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/7290820
• 关键词: Inhibitors; Tyrosine; Kinase; Dependent; Signalling

Pharmacological agents are being developed to modulate phosphotyrosyl (pTyr) dependent cell signalling. Emphasis is on inhibitors of pTyr dependent binding interactions, which are mediated by src homology 2 (SH2) domains and on protein tyrosine phosphatase (PTP) inhibitors. In the SH2 domain area, development of cell permeable growth factor receptor-bound protein 2 (Grb2) antagonists is being undertaken as potential new therapeutics for a variety of cancers including erbB-2 and Met dependent cancers. During the reporting period novel macrocycles were prepared that represented conformationally constrained tetrapeptide-mimicking variants of our earlier tripeptide inhibitors. In an effort to explore and extend the macrocyclization approach a variety of new chemistries were examined. These include a several different olefin methasis reactions, [2+3] azide - alkyne cycloaddition reactions and ring closure using beta-aminomethylene groups. These investigations have advanced the field of macrocyclic peptidomimetic synthesis. As part of a collaborative effort with NCI clinical investigators, Grb2 signaling inhibitors were studied against von Hippel-Lindau (VHL)-dependent kidney cancers that rely on Grb dependent signaling pathways. In cellular studies, certain of these agents inhibit hepatocyte growth factor (HGF)-induced cell migration in Met containing fibroblasts at nanomolar concentrations and inhibit tubule formation potentially involved in angiogenesis. Metastasis model animal studies are currently ongoing. Biotinylated variants of select potent Grb2 SH2 domain signaling inhibitors were also prepared and are being used as pharmacological tools to identify intracellular targets. Efforts were also begun to develop SH2 domain-directed peptide mimetic inhibitors of Shc-dependent signaling. Shc proteins are non-catalytic SH2 domain-containing docking modules that participate in a variety of cell-regulatory processes associated with proliferation, survival and apoptosis. Shc as well as Grb2 proteins are particularly important for down stream signaling of receptor tyrosine kinases (RTKs), where they have been shown to link activation of the cytoplasmic kinase domains with Ras effectors. Shc has also been shown to serve as a critical angiogenic switch for VEGF production downstream from the Met and ErbB2 RTK oncoproteins, where recruitment of Shc but not Grb2 has been shown to be a required event. Accordingly, disruption of Shc-dependent signaling through blockade of its SH2 domain interactions may afford a new therapeutic approach to cancers reliant on disregulation of such RTKs. In the phosphatase area, a structure-based approach toward PTP inhibitor design has been pursued. Using as a display platform, a tripeptide sequence derived from an epidermal growth factor receptor (EGFr) autophosphorylation site, we had previously examined a panel of synthetic pTyr mimetics for inhibitory potencies against YopH, which is a pathogenic PTP component of Yersinia pestis, the causative agent of plague. Certain of these tripeptides exhibited binding constants in the single-digit micromolar range. Work during the reporting period continued to optimize these tripeptide leads as potential therapeutics for the treatment of plague. Currently, known high affinity YopH inhibitors are being prepared for co-crystallography with the YopH protein and X-ray crystallographic structure determination. Information gained in this way will be used to design focused libraries of inhibitors. Inhibitors derived from this work may have therapeutic value against the use of Yersinia pestis as a bioterrorism agent.

正在开发药理学剂来调节磷酸酪糖基（PTYR）依赖性细胞信号传导。重点是PTYR依赖性结合相互作用的抑制剂，这些相互作用是由SRC同源性2（SH2）结构域和蛋白质酪氨酸磷酸酶（PTP）抑制剂介导的。在SH2结构域区域中，可渗透生长因子受体结合蛋白2（GRB2）拮抗剂的发展是针对包括ERBB-2和MET依赖性癌症在内的各种癌症的潜在新疗法。在报告期间，制备了新型大环，该新大环体代表了我们早期三肽抑制剂的构象约束四肽的变体。为了探索和扩展大环化方法，研究了各种新的化学成分。这些包括几种不同的烯烃反应，[2+3]叠氮化物-alkyne Cycloadition反应和使用β-氨基甲基烯基团的环闭合。这些研究已推进了大环肽合成的领域。作为与NCI临床研究者的合作工作的一部分，对GRB2信号抑制剂进行了研究，以依靠依赖GRB依赖的信号通路的Von Hippel-Lindau（VHL）依赖性肾脏癌。在细胞研究中，这些药物中的某些抑制肝细胞生长因子（HGF）诱导的细胞迁移在含有纳摩尔浓度的成纤维细胞中的MET迁移，并抑制潜在参与血管生成的小管形成。转移模型动物研究目前正在进行中。还制备了精选有效GRB2 SH2域信号抑制剂的生物素化变体，并被用作鉴定细胞内靶标的药理工具。还开始努力开发SH2域定向的肽模拟于SHC依赖性信号的抑制剂。 SHC蛋白是非催化SH2结构域的对接模块，参与与增殖，生存和凋亡相关的各种细胞调节过程。 SHC以及GRB2蛋白对于受体酪氨酸激酶（RTKS）的下流信号传导尤为重要，在该信号中，它们已被证明可以将细胞质激酶结构域的激活与RAS效应子联系起来。 SHC还被证明是MET和ERBB2 RTK Oncoproteins下游的VEGF生产的关键血管生成开关，在此招募SHC但不是GRB2的募集是必需的事件。因此，通过阻断其SH2结构域相互作用的阻断SHC依赖性信号的破坏可能为依赖于这种RTK的癌症提供了一种新的治疗方法。在磷酸酶区域，已经采用了基于结构的PTP抑制剂设计方法。使用作为显示平台，是源自表皮生长因子受体（EGFR）自磷酸化位点的三肽序列，我们以前曾检查过一组合成PTYR模拟物，以抑制Yerph Yersinia Pestis的病原PTP成分，是Pestis的抑制性PTP成分，是Pestis的耶尔森氏菌。这些三肽中的某些在单位微摩尔范围内表现出结合常数。报告期间的工作继续优化这些三肽铅作为治疗鼠疫的潜在治疗剂。目前，正在为YOPH蛋白和X射线晶体结构测定的共结晶准备已知的高亲和力YOPH抑制剂。以这种方式获得的信息将用于设计抑制剂的集中库。从这项工作中得出的抑制剂可能具有用于使用耶尔森氏菌作为生物恐怖剂的治疗价值。