Splicing variant of hepcidin mRNA.

Hepcidin is a main regulator of iron metabolism, of which abnormal expression affects intestinal absorption and reticuloendothelial sequestration of iron by interacting with ferroportin. It is also noted that abnormal iron accumulation is one of the key factors to facilitate promotion and progression of cancer including hepatoma. In this study, we firstly revealed that a new alternative HAMP transcript was found in hepatoma-derived cell line HLF, which was identical to the wild-type preprohepcidin sequence except lacking of an internal 60 bases. In addition to HLF, most of hepatoma-derived cell lines have significant copy numbers of variant-type hepcidin mRNA by a copy-based-digital PCR. Furthermore, the copy number of hepcidin mRNA variant was significantly higher in serum exosomes of hepatocellular carcinoma patients. The quantification of exosomal hepcidin mRNA variant may serve as a potential new biomarker for HCC diagnosis.