Design, synthesis, and anticancer evaluation of arylurea derivatives as potent and selective type II irreversible covalent FGFR4 inhibitors

Aberrant FGF19/FGFR4 signaling has been demonstrated to be an oncogenic driver of growth and survival in human hepatocellular carcinoma (HCC). At present, the development of FGFR4-specific drugs has become a hotspot in tumor-targeted therapy research. However, no selective FGFR4 inhibitors have been approved by FDA so far. Currently, most of the reported FGFR4 inhibitors that use a covalent targeting strategy to be selective are typical type I inhibitors with a single type. Here, based on Ponatinib, we designed and synthesized a series of arylurea derivatives as novel type II irreversible covalent inhibitors of FGFR4. Among them, the representative compound 6v exhibited an IC50 value of 74 nM against FGFR4 and antiproliferative potency of 0.25 μM and 0.22 μM against Huh7 and Hep3B cell lines. Western blotting results showed that compound 6v significantly inhibited the phosphorylation of FGFR4 and its downstream signaling factors AKT and ERK in a dose-dependent manner in Hep3B cell. These results showed that this series of compounds, as type II irreversible FGFR4 inhibitors, are worthy of further research and structural optimization.