Screening and validation of tumor-associated genes in human hepatocellular carcinoma tissues

We used gene expression profile detected by Gene chip to investigate the pathogenesis of hepatocellular carcinoma (HCC) and screen for early diagnostic markers.

Differentially expressed genes between HCC and normal liver tissues were screened by using Gene Expression Profile Chip with 14,500 distinct genes. Some selected differentially expressed genes were validated using reverse transcription polymerase chain reaction (RT-PCR) for the gene level and using immunohistochemistry for the protein level.

A total of 2757 (19.01%) differentially expressed genes were totally screened by Gene chip analysis, showing 1772 up-regulated and 984 down-regulated genes. These genes were initially classified into 16 groups according to their functions. The RT-PCR results strongly supported the Gene chip data. By immunohistochemistry, two proteins showed expression levels that corresponded to the Gene chip results, while expression levels found for one protein were different to the Gene chip results.

Gene chip is a useful tool for screening tumor-associated genes and it contributes to the understanding of pathogenesis of HCC. RT-PCR and immunohistochemistry can be used to validate the tumor-associated genes screened by Gene chip analysis.