In HCC patients, the transcriptional levels of peripheral Cldn1 and TGF-β in PBMCs were strongly positively correlated with each other, and both were inversely correlated with the serum ALB concentration; however, they were positively correlated with ALT, AST, BiL, AFP, and FIB-4 scores and with the serum levels of IL-10, IL-12, and sCD163. This evidence concerns the gene CLDN1 and hepatocellular carcinoma.