APOH and hepatocellular carcinoma: This assay was performed through a two-step workflow—Step 1: click chemistry-mediated enrichment of HCC EVs in 1.0-mL plasma by methyltetrazine (mTz)-grafted EV Click Beads [22] in conjunction with the use of a 3 trans-cyclooctene (TCO)-grafted antibody cocktail targeting three HCC EV surface markers (EpCAM, CD147, and ASGPR1), and Step 2: Absolute quantification of six HCC EV-specific genes (ALB, APOH, FGB, FGG, H2AX, and TF) by RT-dPCR.