Antiemetic drug fosaprepitant exerts anti-tumor effects against NSCLC by targeting FAK to inhibit AKT and JNK/c-Jun pathways

Non-small cell lung cancer (NSCLC) is an aggressive malignancy with a poor prognosis. Abnormal expression of focal adhesion kinase (FAK) is closely linked to NSCLC progression, highlighting the need for effective FAK inhibitors in NSCLC treatment. In this study we conducted high-throughput virtual screening combined with cellular assays to identify potential FAK inhibitors for NSCLC treatment. Fosaprepitant (FOS), a clinical antiemetic drug, exhibited a high affinity for FAK with a K_D value of 4.35 × 10⁻⁵ M. The direct interaction between FOS and FAK was confirmed by molecular docking, molecular dynamics, drug affinity responsive target stability and surface plasmon resonance analysis. We showed that FOS (15, 25 μM) dose-dependently inhibited the proliferation, migration and invasion of A549 and H1299 cells by targeting FAK. The IC₅₀ values in inhibiting the cell viability at 24 h were 73.05 and 126.1 μM, respectively. Knockdown FAK reversed the inhibitory effects of FOS on A549 cells. Using RNA sequencing and Western blotting analysis, we demonstrated that FOS treatment led to downregulation of the AKT and JNK/c-Jun signaling pathways in A549 and H1299 cells. Importantly, point mutation analyses revealed that FOS primarily targeted the Y925 phosphorylation site on FAK. In A549 cells xenograft nude mouse model, administration of FOS (20, 60 mg/kg, i.p. every 2 d for 2 weeks) dose-dependently suppressed the tumor growth. Collectively, FOS exhibits significant anti-NSCLC activity both in vitro and in vivo by binding to FAK and inhibiting its phosphorylation, thereby blocking the AKT and JNK/c-Jun signaling pathways. These results suggest FOS as a novel FAK inhibitor for NSCLC treatment.