Adenovirus-mediated siRNA inhibited survivin gene expression induces tumor cell apoptosis in nude mice.

In order to research the survivin gene's action on an animal tumor, we used an adenovirus-mediated siRNA system to inhibit the expression of survivin in an animal model of hepatocarcinoma using nude mice. We constructed a hepatocarcinoma model with nude mice using the hepatocarcinoma cell line HepG2 and divided the mice into four groups depending on the injection dose of AdsiRNA-survivin. We injected the constructed survivin-siRNA adenovirus into tumor-bearing nude mice, observed tumor growth, and determined the tumor growth curve. We then detected tumor cell apoptosis using a TUNEL kit that can assay sliced DNA in tumor cells. The growth of tumors injected with a high or low dose of AdsiRNA-survivin was obviously inhibited, and this level of inhibition was positively correlated with the injected dose of adenovirus. Results of the TUNEL test showed that many of the apoptotic cells were brown in color with concentrated nuclei and an irregular cell shape for both the high and low injection doses. The number of apoptotic cells decreased by group in the order of the high dose group, the low dose group, the AdsiRNA-U6 group, and the PBS group. In conclusion, our results demonstrated that an adenovirus-mediated siRNA system can be used for animal experiments in vivo. AdsiRNA-survivin efficiently inhibited tumor growth and induced tumor cell apoptosis, and it did so in a dose-dependent manner.