[Inhibitory effect of siRNA on heparanase expression and invasion ability of gastric cancer cells: an in vitro experiment].

ABSTRACT

OBJECTIVE: To investigate the inhibitory effect of siRNA on heparanase expression and invasion ability gastric cancer cells. METHODS: A heparanase mRNA-targeting double-stranded siRNA was designed with the bioinformatics technology. Human gastric cancer cells of the line SGC7901 were cultured and transfected with the siRNA of the concentrations of 5, 10, 20, and 40 nmol/L respectively. Forty-eight hours later RT-PCR and Western blotting were applied to detect the mRNA and protein expression of heparanase. Millicell chamber assay was performed to detect the invasion ability of the SGC7901 cells. Blank control group and negative control group were set. RESULTS: The mRNA expression level of the cells transfected with the siRNA of the concentrations 20 nmol/L and 40 nmol/L were 0.207 +/- 0.095 and 0.200 +/- 0.085 respectively, both significantly lower than that of the control group (0.60 +/- 0.09, both P < 0.05). Western blotting showed that the protein expression of heparanase of the different siRNA subgroups were all decreased dose-dependently; and no heparanase band was seen in the 40 nmol/L subgroup. The invasion rate of the siRNA group was significantly lower than that of the control group with a mean inhibition rate of (61 +/- 36)%. CONCLUSION: RNAi inhibits the expression of heparanase and the invasion ability of human gastric cancer cells. Heparanase may be a new target in treatment of gastric cancer's metastasis.