Gene expression analysis of human hepatocellular carcinoma by using full-length cDNA library

Hepatocellular carcinoma (HCC) is a leading cause of death worldwide. Hepatitis B virus (HBV) or hepatitis C virus (HCV) infection has been shown to cause hepatic carcinogenesis. A total 58,251 of cDNA clones of full-length cDNA libraries of HBV and HCV-infected HCC and their surrounding non-tumor tissues, respectively, were sequenced and analyzed by blasting against GENEBANK maintained by NCBI. About 180 and 279 of genes were shown an obviously increased and decreased expression patterns between HCC tissue and its adjacent non-tumor tissue. The candidate genes consisted of the genes encoded liver specific metabolism enzymes, secretory functional proteins, proteases and their inhibitors, protein chaperon, cell cycle components, apoptosis-related proteins, transcriptional factors, and DNA binding proteins. Several genes were further investigated by using real-time PCR to confirm the gene expression levels in at least 24 pairs of HCC tissues and adjacent non-tumor tissues. The results showed that genes encoded reticulon 4, RGS-1, antiplasmin, and kallikrein B were down-regulated with the average of 2.8, 8.5, 3.2, and 10.5-fold, respectively. Our results provide crucial candidate genes to develop clinical diagnosis and gene therapy of HCC.