SOX9 and neoplasm: In detail, 3/3 metastatic nodules originating from SOX9+ primary lesions expressed SOX9; among the 8 cases in which apparent SOX9 immunoreactivity was not detected in the primary lesion, 6 metastatic nodules showed SOX9 expression (Fig. 6B and Supplemental Table 3), suggesting that SOX9 expression is associated with postoperative tumor recurrence/metastasis in HCC.