The aim of this study was to identify serum proteins with differential concentrations among HCC patients infected with HBV with BCP double mutations, asymptomatic HBsAg carriers with BCP double mutations and individuals negative for HBsAg, using iTRAQ (isobaric tags for relative and absolute quantification) [13] and liquid chromatography-tandem mass spectrometry. This evidence concerns the gene OPN1SW and hepatocellular carcinoma.