雷帕霉素类新型mTOR变构抑制剂的发现及其构效关系研究

The immunosuppressant drug rapamycin, was firstly identified as mTOR allosteric inhbitor, and its derivatives have been successfully developed as anti-cancer drugs. Therefore, finding rapamycin derivatives with better anti-cancer activity has been proved to be an effective way in discovering new targeted anti-cancer drugs.In our previous research, several rapamycin derivatives have been synthesized and studied on their biological activity. During the course, an analog named as RA-1 was found to have stronge anti-cancer activity. Base on above results, we have already applied for the CN and PCT patent respectively. In continuation of our previous research, we will design five novel series of RA-1 derivatives using bioisosterism, opening ring, and configuration inversion methods, as well as computer virtual screening. Following, structure modification will be carried out on the side chain of benzothiazole at C43 position in RA-1. After synthesizing target compounds, they will be screened for anti-cancer and immunosuppressive activities in vitro and in vivo. According to the above results, the structure-activity relationship will be analyzed. Our aim is to find one/two novle mTOR targeted candidate drugs, which will be expected to become the new anti-cancer drug of PI3K/AKT/mTOR pathway in the near future.

免疫抑制剂雷帕霉素是第一个被发现的mTOR变构抑制剂，其衍生物已被成功开发为PI3K/AKT/mTOR通路靶向抗癌药物。因此，寻找抗癌活性显著的新型雷帕霉素衍生物是靶向抗癌药物发现的有效途径。通过前期研究，课题组合成了系列雷帕霉素衍生物，经生物学活性研究发现了抗癌活性很强的噻唑基雷帕霉素衍生物RA-1，已申请国内外发明专利。为寻找更为有效的候选化合物，本课题拟在RA-1结构基础上，采用电子等排、开环、构型翻转法并结合计算机虚拟筛选，设计出五个系列的RA-1衍生物；通过对RA-1结构中的C43位噻唑侧链进行选择性修饰，实现80个目标化合物的合成；经体内外生物学活性研究，阐明其结构与抗癌等生物学活性之间的关系。通过本课题的研究，以期发现1-2个新mTOR靶向抗癌候选药物，为形成具有自主知识产权的PI3K/AKT/mTOR通路靶向抗癌新药奠定基础。

雷帕霉素是首个被发现的mTOR变构抑制剂，其衍生物依维莫司和替西罗莫司已被成功开发为mTOR通路靶向抗癌药物。基于此，本项目开展新型雷帕霉素衍生物的结构修饰和优化，以求获得抗癌活性更为显著的新型雷帕霉素衍生物。.通过系统的研究，本项目以前期获得的RA-1为先导化合物，通过结构修饰和优化获得6种不同结构类型的新雷帕霉素衍生物70个。利用SRB体外模型完成化合物的抗癌活性评价，获得14个体外抗癌活性提高的新化合物。通过分子生物学等体外分析方法，采用流式细胞术和Western blot蛋白电泳分析目标化合物对诱导癌细胞凋亡、阻滞癌细胞周期及抑制mTOR、4EBP1、p70S6K1、S6的磷酸化和cyclin D1的表达水平，进一步探索其潜在作用机制。同时，采用MOE计算机辅助药物设计软件对抗肿瘤活性强的两个化合物19c和FIM-X145进行蛋白模拟对接，从分子水平首次发现，在C-43和C-28两个羟基活性位点上分别引入的侧链基团，在与靶蛋白结合时，其新引入侧链都是在结合口袋之外。通过对人癌异体移植模型的体内药效研究，FIM-X13和FIM-X145的体内抑瘤生长能力不及依维莫司。.通过以上研究，分别在主流期刊Archiv der pharmazie，Chemical pharmaceutical bulletin上发表学术论文3篇，申请国家发明专利3项，培养硕士研究生2名。通过本项目的研究，获得体外抗肿瘤活性较雷帕霉素增强的新化合物14个；通过分子生物学深入阐明其潜在作用机制；通过计算机辅助分子模拟对接发现，从分子水平进一步说明化合物活性提高的潜在原因；本项目的研究结果，为开发新型mTOR抗肿瘤药物提供科学依据和理论指导。