Whole-genome CRISPR-Cas9 loss-of-function screening has revealed that FGFR3 limits the activity of FGFR4-selective inhibitors in inducing cell death, whereas the pan-FGFR inhibitor erdafitinib exhibits stronger efficacy than FGFR4-selective inhibitors in inhibiting the growth and survival of FGF19-positive HCC cells 285. The gene discussed is FGF19; the disease is hepatocellular carcinoma.