基于单体双重异质修饰的TRAIL偶联药物及其靶向抗肿瘤活性机制

项目名称： 基于单体双重异质修饰的TRAIL偶联药物及其靶向抗肿瘤活性机制

项目编号： No.81502971

项目类型： 青年科学基金项目

立项/批准年度： 2016

项目学科： 医药、卫生

项目作者： 潘利强

作者单位： 浙江大学

项目金额： 17.9万元

中文摘要： TRAIL能够诱导大部分肿瘤细胞凋亡，而对正常细胞无损伤，是极具潜力的新型大分子靶向药物。然而，半衰期短（5~30 min）及肿瘤细胞先天和获得性耐药的存在制约了TRAIL的进一步应用。在前期研究中，我们利用TRAIL偶联药物（海兔毒素，MMAE）的靶向抗肿瘤策略使其耐药性问题得以改善，相关成果发表于Advanced Materials（IF 15.4）。但TRAIL偶联药物的深层次活性和代谢机制仍待挖掘，且TRAIL的药代动力学缺陷也亟需克服。因此，本研究将针对TRAIL三聚体的结构特征，利用偶联反应中的空间位阻效应在各个单体的突变位点上先后修饰PEG和MMAE，以达到双重异质修饰TRAIL三聚体的目的，并借此同时解决半衰期短和耐药性的难点。此外，本研究将以PEG/MMAE比例为唯一初始变量，研究TRAIL偶联药物细胞水平代谢机制，结合组织分布和药效学阐释其靶向抗肿瘤活性的内在机制。

中文关键词： 肿瘤坏死因子相关凋亡诱导配体；抗体偶联药物；蛋白质药物；蛋白质修饰；细胞代谢动力学

英文摘要： After binding with death receptors (DR4 and DR5), homotrimeric tumor-necrosis-factor (TNF)-related apoptosis-inducing ligand (TRAIL) could induce apoptosis in various cancer cells instead of most normal human cell types, followed with the internalization of ligand-receptor complex by tumor cells. However, poor pharmacokinetics and resistance within some tumor cell lines have been the major obstacles during the preclinical or clinical application of TRAIL. The half-life of TRAIL114-281 (114 to 281 amino acids) was revealed to be no more than 30 minutes across species. To overcome TRAIL resistance resulted from the defects of intrinsic apoptotic pathway in some tumor cells, the internalization process has been utilized to deliver highly toxic chemical (Monomethyl Auristatin E, MMAE) into cytoplasm via TRAIL-MMAE conjugates in the previous study, and the results were published in top journal Advanced Materials (IF 15.4). The released MMAE could inhibit tumor cell division by blocking the polymerization of tubulin, after the enzymatic hydrolysis of conjugates in lysosome. Therefore, maleimido activated PEG (polyethylene glycol) and MMAE (Monomethyl Auristatin E) were applied to site-specifically conjugate with the mutated cysteines from different monomers of TRAIL successively, taking advantage of steric effects involved within TRAIL mutant conjugations. What’s more, the affinity and activity of PEG-TRAIL-MMAE conjugates could be altered along with different PEG/MMAE ratios, followed by further changed pharmacokinetics (PK) and pharmacodynamics (PD). Thus this project will attribute the fundamental mechanisms of antitumor activities of TRAIL conjugates to their cellular metabolic behaviors, after the synthesis of PEG-TRAIL-MMAE conjugates with various PEG/MMAE ratios as model molecules.

英文关键词： TRAIL;antibody-drug conjugates;protein drug;protein modification;cellular pharmacokinetics