457 Impact of MT2 Melatonin Receptor Deletion on Cellular Senescence in Cholangiocytes Isolated From Mice After Cholestatic Liver Injury

A S L D A b st ra ct s BGJ398, a pan-FGFR inhibitor currently being employed in human trials, resulted in a significant increase in cellular apoptosis. Tumor tissue from mice sacrificed 10 weeks after biliary oncogene transduction of AKT and YAP also demonstrated increased expression of FGFR 1-4. BGJ398 treatment resulted in a significant reduction in tumor burden and increase in tumor cell apoptosis as assessed by the TUNEL assay in our mouse model of CCA. In Conclusion, YAP is a critical oncogene in CCA and promotes biliary carcinogenesis, in part, via upregulation of FGFR. In a murine genetic model of CCA, the FGFR specific inhibitor BGJ398 significantly reduces tumor burden by inducing apoptosis. Thus, inhibition of FGFR represents a promising therapeutic approach in YAP-driven human CCA.