Two-dimensional electrophoresis map of the human hepatocellular carcinoma cell line, HCC-M, and identification of the separated proteins by mass spectrometry

Currently, one of the most popular applications of proteomics is in the are a of cancer research. In Africa, Southeast Asia, and China, hepatocellular carcinoma is one of the most common cancers, occurring as one of the top fi ve cancers in frequency. This project was initiated with the purpose of sep arating and identifying the proteins of a human hepatocellular carcinoma ce ll line, HCC-M. After two-dimensional gel electrophoresis separation, silve r staining, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) analyses, tryptic peptide masses were searched for matches in the SWISS-PROT and NCBI nonredundant databases. Approximate ly 400 spots were analyzed using this approach. Among the proteins identifi ed were housekeeping proteins such as alcohol dehydrogenase, alpha-enolase, asparagine synthetase, isocitrate dehydrogenase, and glucose-6-phosphate l -dehydrogenase. In addition, we also identified proteins with expression pa tterns that have been postulated to be related to the process of carcinogen esis. These include 14-3-3 protein, annexin, prohibitin, and thioredoxin pe roxidase. This study of the HCC-M proteome, coupled with similar proteome a nalyses of normal liver tissues, tumors, and other hepatocellular carcinoma cell lines, represents the first step towards the establishment of protein databases, which are valuable resources in studies on the differential pro tein expressions of human hepatocellular carcinoma.