To validate PRDM1-induced tumoral PD-L1 upregulation in HCC cell lines, PRDM1 was overexpressed using the LV-PRDM1 vector in Hep3B cells and was suppressed in Huh7 cells using CRISPR Cas9-targeted mutation (sgPRDM1) (Supplementary Fig. 2a). This evidence concerns the gene CD274 and hepatocellular carcinoma.