Arbelaiz et al. analyzed the expression of exosomal proteins in the blood of HCC patients and healthy people, and found that G3BP and polymeric immunoglobulin receptor (PIGR) were significantly elevated in the exosomes of the former, and the prediction efficacy of these two proteins for HCC is superior to the widely used marker AFP [206]. The gene discussed is AFP; the disease is hepatocellular carcinoma.