Computational revealing Infigratinib resistance to the FGFR2 N549H and N549K mutations

Fibroblast growth factor receptor 2 (FGFR2) is a receptor tyrosine kinase that is involved in many human cancers such as intrahepatic cholangiocarcinomas and hepatocellular carcinomas. The clinically acquired FGFR2 N549H/K mutations make the treatment of Infigratinib ineffective. Here, molecular docking, multiple-replica molecular dynamics (MD) simulations, and binding free energy calculations were used to reveal the mechanism of Infigratinib resistance to the FGFR2 N549H/K mutants. MD simulations indicated that both N549H/K mutations disrupt the local hydrogen bonds or salt bridges formed by His544, Asn549, Glu565, and Lys641. Binding free energy calculation results suggested that both the decrease of van der Waals interactions and electrostatic interaction are responsible for weakening the binding affinity of Infigratinib to the FGFR2 N549H/K mutants. Residue-based energy decomposition analysis further showed that the interactions of Infigratinib with key residues Leu487, Glu565, Ala567, Gly570, and Leu633 become significantly weaker in the N549H/K mutants compared to the wild-type kinase. We anticipate that our results will provide a useful guide to design potential inhibitors against the FGFR2 N549H/K mutants.