CD274 and hepatocellular carcinoma: Table 1 shows the baseline data of patients and healthy controls. The expression level of PD-L1 in circulating exosomes was detected by ELISA. We detected 4.90±4.26, 4.57±3.25 pg/mL, and 1.61±0.66 pg/mL of PD-L1 in exosomes in patients with CHB, HCC, and HC, respectively. Compared with HC, levels of PD-L1 in circulating exosomes in patients with CHB and HCC were significantly increased (F =7.46, P=0.001). However, expression levels of PD-L1 in circulating exosomes between patients with CHB and HCC were not statistically significant (Figure 2).