PDCD1 and neoplasm: In the present study, under RFA treatment, we observed that compared with the PD-1 knockdown group, significantly decreased proliferation of H22 cells, increased apoptosis rate of H22 cells, enhanced cytotoxicity of CD8+ T cells, and decreased tumor growth in H22 cell xenograft model were observed in the PD-1 + TGF-β knockdown group, indicating that blocking TGF-β synergistically promoted the antitumor effect of RFA combined with PD-1 blockade therapy.