Abstract: Objective To design siRNA targeting to survivin and construct an eukaryocytic expression vector pSUPER/survivin,then transfected it into cervical cancer cell line HeLa and evaluated the effects of siRNA against survivin gene on cell cycle of cervical cancer cell line HeLa irradiated with γ-rays.Methods The primer was synthesized,siRNA targeting to survivin was obtained,linked with the vector pSUPER and sequenced.The correct pSUPER/survivin was transfected into HeLa cells and the expression of survivin gene in Hela cells was detected by RT-PCR and Flow Cytometry(FCM).In the present study,the effects of survivin gene transfection combined with irradiation on cell cycle distribution were analysed by FCM.Result Recombinant eukaryocytic expression vector pSUPER/survivin was successfully constructed.FCM results indicated that the expression of survivin gene is significantly suppressed in pSUPER/survivin transfected cells compared with non-transfected cells or empty vector pSUPER transfected cells.After γ-ray irradiation,HeLa cells transfected with pSUPER/survivin induced less proportion of S phase and G₂/M arrest.Conclusion Recombinant eukaryocytic expression vector pSUPER/survivin was successfully constructed.siRNA against survivin enhanced radiosensitivity through execution of apoptosis,induction less proportion of S phase and G₂/M arrest,it may be a potential target for improving radiosensitivity

Key words: siRNA, survivin gene, γ-ray, HeLa cell, Cell cycle