Our team previously elaborated the SRY-related high-mobility group box 18 (SOX18) gene acts as the downstream executor of FGF19/FGFR4 and SOX18 in turn upregulates the expression of FGFR4, which formed FGF19-SOX18-FGFR4 positive circuit to facilitate the metastasis of hepatocellular carcinoma 50. The gene discussed is SOX18; the disease is hepatocellular carcinoma.