Design of SMAC Peptidomimetics and Nonpeptidic Mimetics

SMAC 肽模拟物和非肽模拟物的设计

• 批准号: 7227711
• 负责人: SHAOMENG WANG
• 金额: $ 26.77万
• 依托单位: UNIVERSITY OF MICHIGAN AT ANN ARBOR
• 依托单位国家: 美国
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-07-01 至 2009-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7227711
• 关键词: Affinity; Amino Acids; Animals; Antineoplastic Agents; Apoptosis; Apoptotic; Area; BIR Domain; BIRC7 gene; Binding; Binding Proteins; Caspase; Cells; Class; Complex; Data; Defect; Fluorescence Polarization; Future; Goals; Grant; In Vitro; Investigation; Length; Link; Malignant Neoplasms; Mediating; Methods; Mitochondria; Molecular Mechanisms of Action; Molecular Target; Normal Cell; Normal tissue morphology; Peptides; Permeability; Pharmaceutical Preparations; Play; Principal Investigator; Protein Overexpression; Proteins; Publishing; Radiation therapy; Reporting; Research; Research Project Grants; Resistance; Resolution; Role; Site; Specificity; Stimulus; Structure; Surface; Tertiary Protein Structure; Therapeutic; Therapeutic Agents; Toxic effect; Work; X-Ray Crystallography; base; cancer cell; cancer therapy; caspase-9; chemical synthesis; design; human BIRC4 protein; immunosuppressive acidic protein; improved; in vivo; inhibitor-of-apoptosis protein; inhibitor/antagonist; interest; mimetics; novel; peptidomimetics; pro-apoptotic protein; programs; protective effect; protein protein interaction; response; small molecule; three dimensional structure; tumor

DESCRIPTION (provided by applicant): Smac/DIABLO was recently discovered as a potent pro-apoptotic protein released from mitochondria. Smac functions as an endogenous antagonist for the Inhibitors of Apoptosis Proteins (lAPs) by binding to the BIR3 domain of X-linked lAP (XIAP) and other lAP proteins and displace caspase-9 from this site. High resolution 3D structures of Smac in complex with the BIR3 domain of XIAP showed that the interaction between them is mediated by only four Smac residues at its N-terminus and a small but well-defined binding groove in the XIAP BIR3 domain, which is suitable for designing small molecule inhibitors. Several recent studies have shown that short Smac peptides (4-8 residues) tethered to a carrier peptide for intra-cellular delivery are effective to overcome apoptosis-resistance of cancer cells in vitro and in vivo by directing targeting lAP proteins, while having no toxicity to normal tissues or to animals. Hence, Smac mimetics that bind to the BIR3 domain in XlAP where Smac and caspase-9 bind may have great therapeutic potential to be developed as an entirely new class of anticancer drugs through overcoming apoptosis-resistance of cancer cells as mediated by lAP protein overexpression. In this project, we propose to design, synthesize and characterize highly potent Smac peptido-mimetics and nonpeptidic mimetics with much improved cell permeability over Smac peptides through the following Specific Aims: Aim 1. (a). Structure-based design of Smac peptido-mimetics and nonpeptidic mimetics based upon the published high-resolution experimental structures of Smac in complex with XlAP BIR3. (b). Determination of high-resolution structures of several most potent Smac mimetics through X-ray crystallography. Aim 2. Chemical synthesis of these Smac mimetics designed in Aim 1. Aim 3. (a). Determination of the binding affinities of these Smac mimetics to the BIR3 domain of XIAP by the fluorescence polarization-based method; (b). Conclusive confirmation of the binding of the most potent Smac mimetics to the XlAP BIR3 protein by NMR methods. Aim 4. Investigation of the activity, specificity and molecular mechanisms of action of the most potent Smac mimetics. Designing highly potent and cell-permeable Smac mimetics is a new and exciting area of research. Our current proposed research represents the first but an essential step toward our long-term goal of developing a novel anticancer drug through targeting apoptosis-resistance in cancer cells mediated by lAP proteins.

描述（由申请人提供）：Smac/DIABLO是最近发现的一种从线粒体释放的强效促凋亡蛋白。Smac作为凋亡蛋白抑制剂（lAPs）的内源性拮抗剂，通过与X-linked lAP （XIAP）和其他lAP蛋白的BIR3结构域结合，并从该位点取代caspase-9。Smac与XIAP BIR3结构域复合物的高分辨率3D结构表明，它们之间的相互作用仅由其n端的4个Smac残基和XIAP BIR3结构域的一个小而明确的结合槽介导，这适合设计小分子抑制剂。最近的一些研究表明，短的Smac肽（4-8个残基）拴在载体肽上进行细胞内递送，在体外和体内通过直接靶向lAP蛋白有效地克服癌细胞的凋亡抵抗，同时对正常组织或动物没有毒性。因此，结合Smac和caspase-9结合的XlAP BIR3结构域的Smac模拟物可能具有很大的治疗潜力，可以通过克服lAP蛋白过表达介导的癌细胞凋亡抵抗，开发出一类全新的抗癌药物。在这个项目中，我们提出设计、合成和表征高效的Smac肽模拟物和非肽模拟物，它们比Smac肽具有更高的细胞通透性，具体目标如下：