MAPK3 and hepatocellular carcinoma: It has been previously reported that hFGF19/FGFR4 signaling leads to the activation of Ras-Raf-Erk1/2 MAPK pathway, and thus functional assay for recombinant scvhFGF19 is conducted using HepG2 hepatocellular carcinoma cell line [8,15].