ABSTRACT
ObjectiveTo explore the effects of small interfering RNA (siRNA) specific to Bcl-2gene on radiosensitivity of esophageal cancer cells. Methods Bcl-2 gene siRNA ( Bcl-2 siRNA ) was induced into esophageal cancer EC9706 cells by lipofectamine.Bcl-2 protein expression and apoptosis of EC9706 cells were detected by flowcytometer. Clone forming assay was used to determine the inhibitory effects of X-ray radiation combined with Bcl-2 siRNA interference. ResultsWhen Bcl-2 siRNA had been induced into EC9706 cells, Bcl-2 protein expression in EC9706 cells was inhibited, and cell apoptosis was increased. Bcl-2 protein expression rates of EC9706 cells induced with Bcl-2 siRNA1, A2, A3 (25.13％ ±2. 04％ ,38.87％ ± 3.34％ , 30.55％ ± 2. 73％ ) were lower than the control group ( 84.28％ ± 1. 47％ )(t =4. 01,3.04,3.64, P ＜ 0. 05 ). After interference, the apoptosis rate of EC9706 cells ( 33.86％ ±1.04％ ) was higher than the control group and siRNA negative group (5.51％ ±0. 14％ and 5.59％ ±0. 46％ ) (t =6. 55,6. 54,P ＜0. 01 ). Bcl-2 gene siRNA interference enhanced X-ray inducing apoptosis of EC9706 cells (56.76％ ± 1.24％ ), which was higher than the radiation alone group ( 24.51％ ± 0. 48％ )(t =3.59,P ＜ 0. 05 ). The D0, Dq, and SF2 of combined treatment group were much lower than those of irradiation alone group . The sensitization enhancing ratio was 1.32 ( ratio of D0 values ) . Conclusions Bcl-2 gene siRNA could enhance the radiosensitivity of esophageal cancer EC9706 cells and may has a good future in clinical practice.