Identification of Specific Protein Markers in Microdissected Hepatocellular Carcinoma

At present, the molecular mechanisms of hepatocellular carcinogenesis are not well-understood, and
hepatocellular carcinoma (HCC) stays one of the most frequent and high-risk metastatic visceral
neoplasms worldwide. For the identification of tumor-relevant proteins, we analyzed microdissected
cells from nontumorous liver tissue (n = 28) and tissue derived from hepatic tumor center (n = 25), as
well as tumor margin (n = 23). We unequivocally identified 53 proteins from hepatic tumor tissues by
peptide fingerprint mapping and SELDI mass spectrometry that were separated using two-dimensional
gel electrophoresis. Among a number of signals that were detected as significantly different in the
protein profiling analysis, we identified for the first time ferritin light subunit (FLS) and adenylate kinase
3 alpha-like 1 (AK3), showing decreased expressions in hepatic tumor, as well as biliverdin reductase
B (BVRB) that was upregulated in HCC. The use of ProteinChip technology in combination with tissue
microdissection gives insight of the complex changes occurring at the protein level in hepatocellular
cancer associated with tumor development and progression and resulted in three new potential
diagnostically useful markers.
Keywords: hepatocellular carcinoma • proteomics • biomarker • tissue microdissection • SELDI-TOF MS • tandem
MS • two-dimensional gel electrophoresis • immunohistochemistry