中文摘要：

目的：探讨NDRG1对体外培养的人肠癌细胞系失巣凋亡的影响。方法：采用慢病毒系统将NDRG1表达单元转入人肠癌细胞系SW620、HCT8中,建立相应的过表达稳定细胞系;通过siRNA的方法干扰HCT116和LOVO细胞系中NDRG1的表达,分别在非贴壁培养的情况下培养48小时,采用流式细胞术和TUNEL染色检测细胞的凋亡情况。结果：在贴壁培养条件下,NDRG1过表达并没有显著影响肠癌细胞的生长及增殖,而NDRG1特异性siRNA干扰HCT116细胞中NDRG1的表达后,其凋亡率无明显变化（P〉0.05）。在悬浮培养条件下,NDRG1过表达的肠癌细胞的失巢凋亡率显著低于正常对照组（P〈0.05）,而用三种不同的siRNA干扰HCT116及LOVO细胞中NDRG1的表达后,其失巢凋亡率均显著高于正常对照组（P〈0.05）。结论：NDRG1在体外可抑制人肠癌细胞的失巢凋亡。

英文摘要：

Objective： To explore the effects of NDRG1 on anoikis of human colon cancer cells. Methods： NDRG1 gene was lentivirally tranduced in the human colon cancer cells（SW620 and HCT8） to establishment stable cell lines, and si RNA was used to decrease the NDRG1 expression in HCT116 and LOVO cell lines. Flow cytometry and TUNEL staining were used to detect the apoptosis in cells treated under suspension condition for 48 h. Results： Under the adherent culture condition, overexpression of NDRG1 had no effects on the growth and proliferation of human colon cancer cells, while the decrease of NDRG1 expression with specific si RNA had no effect on the apoptosis in HCT116 cells（P〉0.05）. Under the suspension culture condition, the anoikis rate of human colon cancer cells overexpressed NDRG1 was significantly lower than that of the control group（P〈0.05）, while the anoikis rates of HCT116 and LOVO cells treated by three kinds of NDRG1 si RNA were both obviously higher than those of the control group（P〈0.05）. Conclusions： NDRG1 functioned in maintaining cell survival of cultured colon cancer cells, mainly manifesting the enhancement of the anoikis-resistance.