Of note, immune-based therapies, such PD-1 inhibitors, have manifested clinical benefits for patients with HCC since 2017.[3,4] Immune checkpoint inhibition is closely related to the critical role of the microenvironment in the progression of solid tumors, with immune activation occurring in 30% of patients with HCC at an early stage.[3,5] Therefore, there is an urgent demand for identifying a new immune-based biomarker as a therapeutic target to improve the outcomes of patients with HCC. Here, PDCD1 is linked to hepatocellular carcinoma.