Expression of angiogenic factors in hepatocarcinogenesis: Identification by antibody arrays

Angiogenesis plays a pivotal role in the progression and metastasis of hepatocellular carcinoma (HCC). However, the expression of a wide range of angiogenic factors remains obscure in HCC. The purpose of the present study was to determine the expression of various angiogenic factors related to hepatocarcinogenesis. We examined the expression of 19 angiogenic factors using antibody arrays in human tissues of various liver diseases, including HCC. We also studied the expression of 19 angiogenic factors in the human HCC cell lines PLC/PRF/5, Hep 3B, HuH7, HLE, HLF and Li-7 and the normal hepatocyte cell line ACBRI3716. In human tissues, although the expression of acidic fibroblast growth factor (aFGF) was found to increase from normal liver to chronic hepatitis, its expression remained unchanged in the transition from chronic hepatitis to HCC. Vascular endothelial growth factor (VEGF) was elevated in liver cirrhosis, but the amounts remained unchanged in the transition from liver cirrhosis to HCC. In contrast, either interleukin-8 (IL-8) or basic fibroblast growth factor (bFGF) was upregulated in HCC. In the HCC cell lines PLC/PRF/5, Hep 3B and HuH-7, the expression of IL-8 was elevated. Although IL-8 was not elevated, bFGF was upregulated in the other HCC cell lines HLE, HLF and Li-7. Thus, either IL-8 or bFGF was upregulated in HCC cell lines and in HCC tissue samples. These data suggest that the upregulation of either IL-8 or bFGF is closely related to the transition from liver cirrhosis into HCC. Therefore, the analysis of the expression of these cytokines using protein arrays may identify novel therapies for individual patients with HCC.