Center of Excellence in Biocatalyst and Sustainable Biotechnology, Department of Biochemistry, Faculty of Science, Chulalongkorn University, Bangkok, 10330, Thailand.
Department of Biochemistry, and Center for Translational Medicine, Faculty of Medicine, Khon Kaen University, Khon Kaen, 40002, Thailand.
Comput Biol Med. 2022 Aug;147:105787. doi: 10.1016/j.compbiomed.2022.105787. Epub 2022 Jun 28.
Mutations in the tyrosine kinase domain of epidermal growth factor receptor (EGFR), including L858R/T790M double and L858R/T790M/C797S triple mutations, are major causes of acquired resistance towards EGFR targeted drugs. In this work, a combination of comprehensive molecular modeling and in vitro kinase inhibition assay was used to unravel the mutational effects of EGFR on the susceptibility of three generations of EGFR tyrosine kinase inhibitors (erlotinib, gefitinib, afatinib, dacomitinib, and osimertinib) in comparison with the wild-type EGFR. The binding affinity of all studied inhibitors towards the double and triple EGFR mutations was in good agreement with the experimental data, ranked in the order of osimertinib > afatinib > dacomitinib > erlotinib > gefitinib. Three hot-spot residues at the hinge region (M790, M793, and C797) were involved in the binding of osimertinib and afatinib, enhancing their inhibitory activity towards mutated EGFRs. Both double and triple EGFR mutations causing erlotinib and gefitinib resistance are mainly caused by the low number of H-bond occupations, the low number of surrounding atoms, and the high number of water molecules accessible to the enzyme active site. According to principal component analysis, the molecular complexation of osimertinib against the two mutated EGFRs was in a closed conformation, whereas that against wild-type EGFR was in an open conformation, resulting in drug resistance. This work paves the way for further design of the novel EGFR inhibitors to overcome drug resistance mechanisms.
表皮生长因子受体（EGFR）酪氨酸激酶结构域的突变，包括 L858R/T790M 双突变和 L858R/T790M/C797S 三突变，是 EGFR 靶向药物获得性耐药的主要原因。在这项工作中，综合分子建模和体外激酶抑制测定被用于揭示 EGFR 突变对三代 EGFR 酪氨酸激酶抑制剂（厄洛替尼、吉非替尼、阿法替尼、达可替尼和奥希替尼）敏感性的影响，与野生型 EGFR 进行比较。所有研究抑制剂对双突变和三突变 EGFR 的结合亲和力与实验数据非常吻合，按顺序排列为奥希替尼>阿法替尼>达可替尼>厄洛替尼>吉非替尼。铰链区的三个热点残基（M790、M793 和 C797）参与了奥希替尼和阿法替尼的结合，增强了它们对突变型 EGFR 的抑制活性。导致厄洛替尼和吉非替尼耐药的双突变和三突变主要是由于氢键占据数量少、周围原子数量少和酶活性位点可及水分子数量多。根据主成分分析，奥希替尼与两种突变型 EGFR 的分子络合处于闭合构象，而与野生型 EGFR 的分子络合处于开放构象，导致耐药性。这项工作为进一步设计新型 EGFR 抑制剂以克服耐药机制铺平了道路。
