OBJECTIVEThis study was designed to investigate the expression and significance of NET-1 in hepatocellular carcinoma (HCC) and analyze the relationship between NET-1 gene expression and clinicopathologic factors in HCC.

METHODSNET-1 gene protein expression was detected by Western blot, fluorescence immunocytochemistry, confocal laser scanning microscopy and immunohistochemistry in 8 cases of HCC tissues, human hepatoma cell line SMMC-7721, and paraffin-embeded sections from 130 cases of HCC.

RESULTSNET-1 gene protein expressed in 8 cases of HCC tissues by Western blot. The NET-1 gene protein positively located in the cytoplasm as irregular granules near Golgi apparatus in SMMC-7721cells, detected by fluorescent immunocytochemistry and observed by confocal laser scanning microscopy. The positive rate of NET-1 protein expression revealed by immunohistochemistry was 96.9% in HCC (126/130). NET-1 Protein expression in HCC was clearly correlative with HCC cytological variants, there were pronounced higher expressions in clear cell type, pleomorphic cell type, and sarcomatous change than that in hepatocytic type (P < 0.05). NET-1 Protein expression in HCC was positively correlative with the histopathologic grading, clinical stages and HCC with hepatitis and cirrhosis (P < 0.05), respectively, and negatively correlated with the presence of patches of necrosis (P < 0.05). But NET-1 protein expression was not associated with AFP level, tumor size and growth patterns, respectively.

CONCLUSIONNET-1 protein is expressed in cytoplasm of HCC cells as irregular granules near Golgi apparatus. NET-1 gene expression may promote the uncontrolled proliferation and abnormal differentiation in HCC cells.