Overexpression of SUMO-1 in hepatocellular carcinoma: a latent target for diagnosis and therapy of hepatoma.

ABSTRACT

PURPOSE: To investigate the expression of SUMO-1 in human hepatocellular carcinoma (HCC) cell lines and clinical HCC samples. METHODS: RT-PCR and Western blot were used to detect the expressions of SUMO-1 in HCC cell lines, clinical HCC samples,and the non-neoplastic liver tissues adjacent to HCC. After transfection of SUMO-1 siRNA into HCC cell line SMMC-7721, the expression levels of Bcl-2, c-Myc and α-tubulin were examined, and MTT assay and cell cycle analysis were carried out as well. RESULTS: Overexpressions of SUMO-1 were detected in HCC cell lines and clinical HCC samples, while the expression level of SUMO-1 in the non-neoplastic liver tissues was significantly lower (P < 0.001). Transfection of SUMO-1 siRNA resulted in 73.43% of maximal silencing efficiency of SUMO-1 in 48 h. The expressions of Bcl-2 and c-Myc were down-regulated coincidentally. SUMO-1 siRNA notably inhibited SMMC-7721 cells proliferation in vitro and increased the ratios of G2 phase and S phase in the cells. CONCLUSIONS: Owing to overexpression of SUMO-1 in HCC and its important role in the development of HCC, SUMO-1 could be a latent target in diagnosis and therapy of HCC.