Serum fucosylated paraoxonase 1 as a potential glycobiomarker for clinical diagnosis of early hepatocellular carcinoma using ELISA Index

Serum paraoxonase 1 (PON1) is highly fucosylated in hepatocellular carcinoma (HCC) compared with liver cirrhosis (LC). Herein, lectin ELISA using Aleuria aurantia lectin (AAL) was established, which specifically measured optical density (OD) value of serum fucosylated PON1. PON1 protein ELISA was applied simultaneously. ELISA Index (OD value of fucosylated PON1/OD value of protein PON1) was introduced to indicate PON1 fucosylation level on its protein level (Fuc-PON1). ELISA Index in training group (90 LC and 90 HCC) was measured and area under the ROC curve (AUROC) was 0.803 with 80 % of sensitivity and 64.4 % of specificity in distinguishing early HCC from LC. Within training group, AFP(-) HCC (20/90) exhibited better AUROC (0.850), higher sensitivity (90 %) and specificity (75 %) than AFP(+) HCC (70/90). An independent testing set (20 LC and 20 HCC) validated the model and 17 HCC patients were successfully predicted. Meanwhile, serum AFP of 43 LC and 43 HCC had an AUROC of 0.760 with sensitivity of 79.1 % and specificity of 53.5 %. Thus, Fuc-PON1 may serve as a glycan biomarker for distinguishing early HCC from LC patients even with low AFP levels.