Lenvatinib Inhibits Intrahepatic Cholangiocarcinoma Growth via Gadd45a-Mediated Cell Cycle Arrest

Abstract Background: Intrahepatic cholangiocarcinoma (ICC) is the second most common primary liver cancer, and its 5-year survival rate is less than 10%. Fibroblast growth factor receptor (FGFR) changes have been observed in 6%-50% of ICC patients, and patients with FGFR mutations have been shown to have more inert tumour biological activity than patients with wild-type FGFRs. Thus, as a pan-FGFR inhibitor, lenvatinib is supposed to play an anti-tumour role in ICC. However, no relevant experiments have been reported.Methods: Patients derived xenograft (PDX) model and cell line derived xenograft (CDX) model were both used for the in vivo study. For in vivo work, ICC cell lines were applied to analyse the effect of Lenvatinib on cell proliferation, cell cycle progression, apoptosis, and the molecular mechanism.Reaults: In the present study, we found that lenvatinib dramatically hindered in vivo tumor growth in ICC patient-derived xenograft models. In addition, by using in vitro experiments in ICC cell lines, we found that lenvatinib dose- and time-dependently inhibited the proliferation of ICC cells and induced cell cycle arrest in the G0/G1 phase. Transcriptional profiling analysis further applied indicated that lenvatinib might inhibit cell proliferation through the induction of cell-cycle arrestment via activating of Gadd45a, it was evidenced by that the knockout of Gadd45a significantly attenuated the cycle arrest induced by lenvatinib, as well as the inhibitory effect of lenvatinib on ICC.Conclusion: Our work firstly found that lenvatinib exerted excellent antitumor effect on ICC, mainly via inducing Gadd45a mediated cell cycle arrest. Our work provides evidence and a rationale for the future use of lenvatinib in the treatment of ICC.