Prognostic value of PD-L1 expression combined with hypoxia-associated immunosuppression in hepatocellular carcinoma.

Background: Hypoxia and immunosuppression are two properties of cancer. This study intends to establish the potential relationship between these two hallmarks in hepatocellular carcinoma (HCC). Materials & methods: A bioinformatics analysis of data obtained from the Cancer Genome Atlas and a retrospective single-center analysis based on a tissue microarray were utilized in this study. Results: We identified a hypoxia-high subtype of patients with immunosuppressive HCC which represented a poor prognosis in the Cancer Genome Atlas cohort. Immunohistochemical analysis of the tissue microarray showed that tumor PD-L1 expression was positively linked to HIF-1α expression, pro-tumor immunocyte infiltration and poor survival in HCC patients. Conclusion: This study provides evidence supporting the correlation between hypoxic signals and immunosuppression in HCC; the combined use of them might improve survival prediction and act as a potential predictor for PD-1/PD-L1 therapy.