Given that FGF1 typically signals through FGFRs, and that FGF1 and FGFR2 expression are positively correlated in iCCA (Fig. S1B), we hypothesized that FGF1 acts through FGFR2.In both RBE and HUCCT-1 cells, rhFGF1 treatment induced FGFR2 phosphorylation and downstream ERK activation in a dose-dependent manner (Fig. 5F).In these cell lines, exogenous rhFGF1 treatment reversed the proliferation inhibition induced by RORγ knockdown with either RORC siRNA or RORγ antagonists, regardless of incubation conditions (Fig. 5G, H). This evidence concerns the gene RORC and infantile convulsions and choreoathetosis.