伊立替康联合X线照射对人结肠癌细胞增殖和凋亡的影响

Effects of irinotecan combined with X-ray irradiation on proliferation and apoptosis of human colon cancer cells

目的:探讨伊立替康(CPT-11)联合X线照射对人结肠癌细胞系HCT-116增殖和凋亡的影响。方法:采用MTT法检测不同浓度CPT-11(10、20、30、40、50μg/mL)作用24 h以及单次不同剂量X线(3、6、9、12、15 Gy)照射对HCT-116增殖的影响;根据实验结果设计对照组、照射组和联合处理组,通过克隆形成实验检测3组细胞的增殖情况;采用AO/EB染色观察3组细胞的凋亡情况;通过Western blot实验检测各组p53和p21蛋白的水平。结果:在10~50μg/mL范围内,CPT-11对于HCT-116细胞增殖呈剂量依赖性抑制作用;经10μg/mL的CPT-11预处理后,分别联合3、6、9、12、15 Gy X线照射,显示联合处理组增殖抑制率大于照射组,差异有统计学意义(P <0.05);与对照组和照射组相比,联合处理组的集落形成数量明显减少(P <0.05);联合处理组的p21和p53水平明显高于其余2组(P <0.05),且凋亡率也显著增加,差异有统计学意义(P <0.05)。结论:伊立替康联合X线照射抑制人结肠癌细胞系HCT-116的增殖,并诱导凋亡,可能与p53和p21的激活有关。

Objective:To investigate the effects of irinotecan(CPT-11)combined with X-ray treatment on the proliferation and apoptosis of human colon cancer cell line HCT-116. Methods:MTT method was used to detect the effects after treatment with different concentrations of CPT-11(10,20,30,40,50 μg/mL)for 24 hours and single dose of X-ray(3,6,9,12,15 Gy)on the proliferation of HCT-116. The proliferation rates of the three groups of cells were detected by clone formation assay,the apoptosis of the three groups was observed by AO/EB staining,and the levels of p53 and p21 protein were detected by Western blot. Results:CPT-11 inhibited the proliferation of HCT-116 cells in a dose-dependent manner in the range of 10~50 μg/mL. After pretreatment with CPT-11 at 10 μmol/L,combined 3,6,9,12 and 15 Gy X-ray irradiation showed that the inhibition rate of proliferation in the combined treatment group was higher than that in the irradiation group,and the difference was statistically significant(P < 0.05);compared with the control group and the irradiation group,the combined treatment group had a dose-dependent inhibition effect on the proliferation of HCT-116 cells. The number of colony formation decreased significantly(P < 0.05);the levels of p21 and p53 in the combined treatment group were significantly higher than those in the other two groups(P < 0.05),and the apoptotic rate also increased significantly(P < 0.05).Conclusion:Iritican combined with X-ray irradiation inhibits the proliferation and induces apoptosis of human colon cancer cell line HCT-116,which may be related to the activation of p53 and p21.