Knockdown of survivin expression by siRNA induces apoptosis of hepatocellular carcinoma cells.

Survivin, a newly identified member of IAP family, is a powerful apoptosis-inhibiting factor. It is expressed in embryonic tissues as well as in the majority of human cancers, but not in most normal adult tissues. The cancer-specific expression of survivin makes it a potential target for cancer treatment. A survivin-specific small inhibitory RNA (siRNA) was introduced into hepatocellular carcinoma cells to investigate its effect on cancer cell apoptosis, growth and sensitivity to chemotherapeutic drugs. It was found that expressions of survivin protein and proliferation index (PI) in siRNA groups were significantly decreased, the apoptosis index (AI) of siRNA groups was significantly higher than those of others groups, and the growth inhibition rate (GIR) of chemotherapeutic drugs in siRNA groups were significantly higher than those of other groups. Our study suggests that the expression of survivin may be significantly decreased in hepG2 cell after siRNA transfection. siRNA targeting survivin could induce cell apoptosis, inhibit cell proliferation and sensitize hepatocarcinoma cells to chemotherapy. Our findings provide preliminary evidence for the therapeutic use of survivin-targeted RNA interference for human tumors that express high levels of this molecule.