SOX9 and hepatocellular carcinoma: We also verified the positive correlation between ID1 expression and SOX9 (p = 6.90e‐05, r = 0.20), EPCAM (p = 5.37e‐06, r = 0.23), CD24 (p = 1.82e‐07, r = 0.27), and CLDN4 (p = 6.04e‐05, r = 0.18) expression in HCC tumor tissue from TCGA datasets (Figure S5D, Supporting Information).