Expression and role of PD-L1 and SOX10 in hepatocellular carcinoma

Background: Hepatocellular carcinoma (HCC) is the fifth most common cancer and second leading cause of cancer-related mortality worldwide. This study aimed to investigate programmed death ligand-1 (PD-L1) and SRY-box transcription factor 10 (SOX10) expression in 191 HCC specimens and to analyze their association with clinicopathological features. Methods: Formalin-fixed, paraffin-embedded HCC specimens were assessed for PD-L1 and SOX10 expression using immunohistochemical staining. Clinicopathological features were obtained from medical records and by reviewing hematoxylin and eosin-stained slides. Results: The proportions of PD-L1-positive and SOX10-positive groups were 13.1% and 46.1%, respectively. PD-L1 positivity was significantly associated with higher T classification (P<0.001). SOX10 positivity was significantly associated with both higher T classification (P<0.001) and higher Edmondson-Steiner grade (P<0.001). In addition, PD-L1 expression showed a borderline correlation with SOX10 expression (P=0.054). In univariate analysis, both PD-L1 and SOX10 expression were associated with shorter overall survival (OS) and relapse-free survival (RFS) in patients with HCC. Conclusions: PD-L1 and SOX10 expression were associated with unfavorable prognostic factors as well as shorter OS and RFS. Further investigation is warranted to elucidate the molecular pathways through which SOX10 may regulate PD-L1 expression and to explore implications for immunotherapy response in patients with HCC.