[The effect of antisense survivin-liposome complex on cell growth, apoptosis and cell cycle in hepatocellular carcinoma cells].

OBJECTIVE: To investigate the effects and the mechanisms of cell growth inhibition in hepatocellular carcinoma cells after induction with antisense survivin-liposome (LIP) complex, and to provide evidence in treatment for hepatocellular carcinoma and tumors expressing survivin.

METHODS: Survivin ODNs was transfected into HepG2 cells mediated by LiP reagent. The expression of survivin mRNA and protein was detected by RT-PCR and Western blot. MTT assay was applied to determine cell proliferation in HepG2 cells. Active caspase-3 and apoptosis rate were evaluated by flow cytometric analysis. The morphological changes were assessed by electron microscopy. Cell cycle was analyzed by flow cytometry in the cell cycle-synchronized hepatocellular carcinoma cells treated with the antisense compound.

RESULTS: Antisense compound efficiently down-regulated survivin expression (mRNA and protein) in a dose-dependent manner with an IC(50) of 250 nmol/L. Its maximal effect was achieved at a concentration of 600 nmol/L, when expression levels were down-regulated by 80%, as revealed by gradually increase of caspase-3-like protease activity and apoptosis rate in a time-dependent manner. Morphological apoptotic changes such as membrane blebbing, loss of microvilli, cytoplasmic vasculization, condensation of cytoplasm and nucleus, chromatin fragmentation, and apoptosis and cell growth inhibition were observed. In the cell cycle-synchronized hepatocellular carcinoma cells, antisense compound induced cell cycle arrest followed by apoptosis. After treated with low concentration of compound, the cell cycle was arrested at S phase or G2/M phase; while at high concentration, the cell cycle was mainly arrested at S phase. Apoptosis was obviously observed and the rate of apoptosis was increased in a time and concentration-dependent manner.

CONCLUSION: Antisense survivin has significant inhibitory effect on growth of hepatocellular carcinoma cells in vitro. This is associated with cell cycle arrest and apoptosis.