Objective：To explore the effects of siRNA targeting survivin combined with radiotherapy on human carcinoma cells SW480.
Methods：The human colorectal carcinoma cell line SW480 was treated with siRNA targeting survivin. The expression level of survivin in transfected SW480 cells was detected by RT-PCR and immunocytochemistry. The effects of siRNA on cell cycle were analyzed by FCM with PI staining. Radiotherapy was combined with siRNAs targeting survivin to study the sensitivity of SW480 induced by siRNA targeting survivin to radiotherapy. The effects of the survivin siRNA combined with radiotherapy on the growth of SW480 were studied by MTT assay. The apoptosis rate of SW480 was analyzed by FCM with annexinV/PI staining.
Results：RT-PCR demonstrated that the expression of survivin was knocked down significantly by the siRNA. Arrest in G2/M phase of the cell cycle was detected by FCM in the SW480 cells transfected with siRNA targeting survivin. The MTT assay showed that siRNA targeting survivin combined with radiotherapy inhibited the growth of SW480 cells more significantly compared with single treatment. More apoptosis cells (almost 35.72%) were detected by FCM in the SW480 cells treated with siRNA combined with radiotherapy.
Conclusions： The small interfering RNA can inhibit survivin of the human colorectal carcinoma cell line SW480. The siRNA targeting survivin combined with radiotherapy can inhibit the proliferation of SW480 and increase the percentage of apoptotic cells markedly. The siRNA targeting survivin can enhance the sensitivity of colorectal carcinoma cell line SW480 to radiotherapy in vitro.