Mengxuan Wang,1,* Zhenhong Xia,1,* Wenyan Nie,1 Chunlong Wang,1 Haoran Nie,1 Shuai Zhang,1 Jiaqi Qiu,1 Yang Yang,1 Cuifang Yao,1 Ling Xu,2 Baijiao An1 

1Shandong Technology Innovation Center of Molecular Targeting and Intelligent Diagnosis and Treatment, Binzhou Medical University, Yantai, Shandong, People’s Republic of China; 2Department of Respiratory Critical Care Medicine, Binzhou Medical University Hospital, Yantai, Shandong, People’s Republic of China

*These authors contributed equally to this work

Correspondence: Ling Xu; Baijiao An, Email 1659996191@qq.com; anbj3@bzmc.edu.cn

Background: The 797S mutation in EGFR disrupts the covalent binding of third-generation inhibitors, causing drug resistance. Currently, no clinically drug fully overcomes this resistance.
Methods: We designed and synthesised a novel EGFR C797S-targeted inhibitor- 5d by introducing structures such as cyclopropyl and sulfonamide with Brigatinib as the lead compound; we identified the target of action by ELISA and molecular docking, and tested its anti-tumor activity and safety in vivo and vitro, as well as its effects on cell cycle, apoptosis and DNA damage.
Results: It was found that there were 10 new small-molecule inhibitors and compound 5d was identified as highly selective with low toxicity. WB confirmed 5d’s inhibition of EGFR and m-TOR pathways. Mechanistic studies revealed 5d induced cell cycle arrest in G2/M phase caused DNA damage and cell apoptosis, increasing apoptotic protein cleaved caspase-3 levels. It also inhibited growth in PC9 cells with an EGFRdel19 mutation. Importantly, 5d also demonstrated superior anti-tumor activity in vivo and was superior to the positive control Brigatinib.
Conclusion: We concluded that cyclopropylsulfonamide 5d derivatives induce cell cycle arrest, apoptosis, and DNA damage by regulating tumor-related genes, thereby inhibiting the proliferation of C797S mutated lung cancer cells.

Keywords: NSCLC, EGFR C797S mutation, EGFR-TKIs, biological activity