三氧化二砷联合顺铂对人结肠癌细胞株colon26抑制作用机理的研究

The Study on Anti-tumor Effect of Arsenic Trioxide Combining with Cisplatin on the Human Colon Carcinoma Cells Line colon26

目的:探讨三氧化二砷(ArsenicTrioxide,As2O3)联合顺铂(Cisplatin,CDP)对人结肠癌细胞株colon26的抑制作用及其机制。方法:用MTT法检测CDP和As2O3对colon26细胞的半数抑制浓度(IC50)及其抑制率。用荧光染色法琼脂糖凝胶电泳观察细胞凋亡形态学变化。用流式细胞术分析细胞周期、细胞凋亡及Bcl-2、Bax蛋白表达。结果:IC50浓度的As2O3、CDP和1/2IC50(CDP)+1/2IC50(As2O3)对colon26细胞的抑制率分别为50.13±0.29%、55.26±0.63%和75.82±0.24%。AO/PI双荧光染色观察,正常对照组、As2O3组、CDP组、联合组细胞凋亡比率依次增加。As2O3处理组G2/M期细胞明显增多,而CDP处理组G0/G1期细胞明显增多,联合用药组则主要表现为S期细胞增多,组间差异有显著性(P<0.01)。CDP处理组与对照组相比Bcl-2/Bax的表达无变化,As2O3与CDP联合作用时和As2O3单独作用时相比,Bcl-2/Bax无变化。结论:低浓度As2O3和CDP联合应用与两药高浓度单独应用相比,对colon26细胞增殖的抑制作用和诱导凋亡能力均有明显增强。As2O3联合CDP抗colon26细胞的作用机制可能与下调Bcl-2蛋白表达有关。

Objective： To study the anti-tumor effect of arsenic trioxide combining with cisplatin on the human colon cancer cells line colon26, and to explore its mechanism of interaction. Methods： The MTY method was used to obtain the IC50 and the inhibition rate of the drugs on colon26 cells. The cells were stained by Acridine Orange and Propidium Iodide Fluorescence to determine the morpological alteration of apoptotic cells and the apoptotic rate. The cell cycle alteration and apoptotic rate of the cells were determined by flow cytometry. The positive rates of colon26 cells with the expression of Bcl-2 or Bax protein were examined with Bow cytometry. Results： The IC50 of cisplatin was 1.23μg/ml, while arsenic trioxide was 2.36μmol/ml. The inhibition rate of As203,CDP and combinatorial treatment group tended to increase. The cells apoptotic rate was 2.68±0.72%, 22.15±1.53%, 24.32±2.14% and 36.69±2.26% for the control group, As2O3, CDP and combinatorial treatment group, respectively. G2/M cells increased obviously in As203 treatment group, G0/G1 cells increased in CDP treatment group, while S cells increased in combinatorial treatment group. There was no change of Bcl-2/Bax in the CDP treatment group or control group. Compared with As203 treatment group, the combinatorial treatment group＇s Bcl-2/Bax had no change. Conclusions： Arsenic trioxide of low concentration combining with . cisplatin of low concentration may increase the anti-osteosarcoma effect, compare to use of arsenic trioxide or eisplatin of high concentration respectively, either in inhibiting colon26 cells proliferation orinducing apoptosis. The mechanisms of interaction are mainly that arsenic trioxide may inhibit the expression of Bcl-2 protein.