Fig 2: Downregulation of ABHD5 induces PD-L1 expression in liver cancer. (A) The CCLE dataset was used to determine the ABHD5 mRNA expression pattern in different liver tumor cells lines. (B) SK-Hep-1 cells and (C) SMMC7721 cells were subjected to knockdown analysis of ABHD5, after transfected knockdown ABHD5 (shABHD5) for 24 h, the cells were collected for PD-L1 analysis by western blotting. (D) Flow cytometry analysis of PD-L1 expression in SK-Hep-1 and (E) SMMC7721 cells, after knockdown of ABHD5 for 24 h, the cells were co-cultured with peripheral blood mononuclear cells (PBMC) or not. With further 24 h culture, the cells were stained with APC conjugated PD-L1 antibody and the subsequent flow cytometry analysis.

Fig 3: D594A mutant results in tumor repression upon PD-L1 blockade. WT and D594A mutant MC38 cells were inoculated subcutaneously (n = 5 mice per group). Anti-PD-L1 was administrated on day 9 and three times a week. The tumor sizes and growth curves of treated and control groups were shown as (A, B). C Analysis of the population of TILs by flow cytometry, including CD3, CD4, CD8, Macrophage and DC cells. D A schematic show that the upregulation of THBS1 promotes the secretion of CXCL9/10 and enhances CD8+ T cells recruitment into D594A, thereby enhancing the anti-PD-L1 response, together with the upregulation of MHC class I and PD-L1. *P < 0.05; **P < 0.01; ***P < 0.001; ****P < 0.0001

Fig 4: BRAF mutation modulates the expression of immune regulatory molecules. A The effect of IFN-γ treatment on the survival of tumor cells analyzed by flow cytometry. B, C The basal and induced expressions of PD-L1 in BRAF WT and mutant MC38 cells detected by flow cytometry and qRT-PCR. D The basal and induced expressions of MHC class I in BRAF WT and mutant cells detected by flow cytometry. E–G The basal and induced expressions of Psmb8, H2-D1 and B2M in BRAF WT and mutant cells detected by qRT-PCR. Cells were treated by 20 ng/mL IFN-γ for 48 h. Three independent replicates were performed for above experiments. *P < 0.05; **P < 0.01; ***P < 0.001; ****P < 0.0001