基于EGFR/HER2/HDAC多靶点非可逆共价抑制剂的设计、合成及活性筛选

EGFR-TKs and HDAC are considered as promising targets for anticancer drug development. The single-target reversible EGFR inhibitors Gefitinib and Erlotinib are FDA-approved cancer drugs. Although these drugs have been effective against non-small cell lung cancers (NSCLCs), their effectiveness is limited by the drug resistance due to the emergence of T790M mutation in EGFR kinase domain. In our previous study, we tried to introduce various Michael acceptors to the quinzoline in order to increase the inhibitory activity.We found that a Cysteine-trapping fragment such as an aziridine was able to to form a covalent bond via a Michael addition with Cys797 within the kinase domain of EGFR. Based on the preliminary biological studies, chemical diversity space and flexible docking results, we aim to design and synthesis new irreversible covalent inhibitors of multi-acting EGFR/HER2/HDAC in this project.We expect to understand the effct of various Cysteine-trapping fragments and substitutions through biological evalution. Further study of structure-activity relationships within the series of synthesized compounds and structural modification would promote us to discover a new generation of potent lead compounds for anticancer drug and to overcome the rapid emergence of drug resistance.

酪氨酸蛋白激酶（EGFR-TKs）和组蛋白去乙酰化酶（HDAC）已成为抗肿瘤药物开发重要靶点, 但以EGFR靶点开发上市的可逆抗肿瘤药物Gefitinib和Erlotinib在治疗非小细胞肺癌时，由于T790M突变易产生耐药性。在前期研究中, 我们发现在EGFR抑制剂喹唑啉的侧链中引入可与其半胱氨酸巯基加成形成共价结合的吖丙啶杂环,可以提高抗肿瘤活性及耐药抵抗性。本项目拟以前期研究工作为基础, 采用化学空间分析方法及柔性分子对接模拟方法，合理设计、合成匹配性能良好的EGFR/HER2/HDAC多靶点非可逆共价抑制剂， 通过活性及耐药性等筛选，考察不同结构的连接桥和取代基对活性和耐药性的影响，进一步进行构效关系研究及结构优化，发现新一代具有抗肿瘤活性高，且克服EGFR抑制剂在治疗过程中耐药性的问题的先导化合物。

本研究利用化学空间分析方法及采用柔性分子对接模拟，合理设计、合成匹配性能良好的HDAC/EGFR/HER2 多靶点非可逆共价抑制剂近100个，通过活性及耐药性等筛选，确定了该类抑制剂的构效关系，所设计的化合物在多种肿瘤细胞中表现中等至良好的抑制活性，特别是对L858R/T790M双突变细胞株H1975也有不错的抑制效果。虽然部分的化合物对激酶的抑制活性不如阳性CO-1686和Afatinib,但是对野生型和突变型的激酶有一定的选择性。进一步对活性相对较好的化合物H-5进行了流式细胞仪分析以及Western Blot实验，化合物H-5显示了对H1975细胞的促凋亡作用以及抑制EGFR磷酸化水平。体内药代动力学研究发现，该类抑制剂的生物利用度为26.1%，综上该抑制剂的研究可为发现可专利的新一代抗肿瘤药物的先导化合物提供基础。同时为了解决不同激酶的选择性和成药性等问题，我们在喹唑啉母核的研究基础上，适当拓宽，采用新的合成方法学，构建多样性含氮杂环母核，为后续发现可靶向突变激酶的新药效团提供研究基础。本研究共发表SCI期刊论文18篇，申请中国发明专利4项，授权中国发明专利4项。