β-eudesmol inhibits cell growth and enhances cell chemosensitivity of NPC through targeting FGF1/FGFR signaling.

Background: Chemoresistance is one ofthe main challenges for advanced NPCtreatment.We previouslyproved LHX2 transcriptionally regulates FGF1 and promotes cancer progression through activating FGF1/FGFR axis,which prompted us toexplore the potential inhibitors for FGFR to improve the therapy response.

Methods: RT-qPCR, immunohistochemistry, western blot assayand immunofluorescencewere applied to verify the gene expression levels. Xenograftmodel as well as lung metastasis model was performed forin vitroassays. Flow cytometry and Tunel stainingwere used to determine the apoptosis of NPC cells.The interaction between β-eudesmol and FGFR1/2 was analyzed by Autodock software.

Results: β-eudesmol inhibited the growth and metastasisof NPCin vivoandin vitro.In addition,β-eudesmol treatment promoted NPC apoptosis and sensitized NPC to cisplatin. β-eudesmol putatively bound to FGFR and blocked the Akt signaling, STAT3 signalingandERKsignaling,which in turn restrainedABCC1 transcription.

Conclusion: β-eudesmol suppressed cell growth, metastasis and chemoresistance in NPC through targetingFGF1/FGFR signaling, thereby blocking the Akt signaling, STAT3 signaling andERKsignaling, as well as down-regulating ABCC1 expression. Our findings provided a novel potential drug for NPC treatment.