Fibroblast
growth factor receptor 4 (FGFR4) has been identified
as a potential target due to its transmission of the FGF19 signaling
pathway, which is critical to hepatocellular carcinoma (HCC). Therefore,
focusing on the specific Cys552 of FGFR4 subtype, we designed and
synthesized a novel family of 1,6-naphthyridin-2(1H)-one derivatives as potent and highly selective FGFR4 inhibitors.
Through detailed structural optimizations, the representative compound A34 exhibited improved FGFR4 inhibitory capability and selectivity
and excellent anti-proliferative activities against FGFR4-dependent
HCC cell lines. Additionally, A34 demonstrated remarkable
antitumor efficacy in a Hep-3B HCC xenograft model, with favorable
pharmacokinetic properties, and low risk of hERG toxicity. A34 also showed moderate inhibitory activities against the FGFR4 V550L
mutant in vitro, which indicates that it has the potential as a novel
anticancer agent for HCC.