AFP and hepatocellular carcinoma: Moreover, by coupling EV Click Chips with a downstream reverse-transcription droplet digital PCR assay, 10 well-validated HCC-specific mRNA transcripts, such as alpha-fetoprotein (AFP), glypican 3 (GPC3), albumin (ALB), apolipoprotein H (APOH), were selectively quantified for the calculation of a digital score.