中文摘要：

目的：探讨候选抑瘤基因NGX6联用5－Fu对结肠癌细胞凋亡的影响。方法：以稳定转染并表达NGX6基因的HT～29细胞与5-Fu联用作为实验组，以PDTC与5－Fu联用的HT－29细胞作为对照组，通过EMSA检测各组结肠癌HT－29细胞核转录因子－κB（NF—κB）的激活情况，利用MTT比色法检测各组细胞增殖的情况，吖啶橙（AO）／溴化乙啶（EB）双染法显微镜观测以及PI／Annexin—V双染流式细胞仪检测各组细胞凋亡情况。结果：稳定转染并表达NGX6基因的HT－29细胞以及应用了PDTC的HT－29细胞NF—κB的激活均明显受到抑制；与5－Fu作用的HT－29细胞组比较。5－Fu联合PDTC作用于HT－29细胞后，HT－29细胞增殖受到明显抑制，5－Fu诱导HT－29细胞凋亡作用增强；与5-Fu联合PDTC作用于HT－29细胞的对照组比较，在诱导细胞凋亡以及抑制细胞增殖方面，稳定转染并表达NGX6基因的HT－29细胞与5－Fu联用组和对照组所取得一致的效果，NGX6基因增强5－Fu对HT－29细胞增殖抑制的能力及诱导HT－29细胞凋亡的能力。结论：NGX6基因抑制了肿瘤细胞NF—κB的激活，具有增强5－Fu诱导结肠癌细胞凋亡的能力，其机制可能是抑制肿瘤细胞NF—κB的激活，NGX6基因对肿瘤的治疗及预后起积极作用。

英文摘要：

Objective： To evaluate the effect of NGX6 with 5-Fu on the apoptosis of colon cancer cells. Methods： The NGX6-transfected HT-29 cell line with 5-Fu was used in the test group. HT-29 cell line with 5-Fu and PDTC was used in the control group. The expression of NF-κB was detected by EMSA. The proliferation of HT-29 cell line was assayed by MTT. The effect of NGX6 on the apoptosis was detected by FCM. HT-29 cells were double-stained by PI/Annexin-V and AO/EB and observed by fluorescence microscopy. Results： The expression of NF-κB was inhibited in NGX6 transfected colon carcinoma cell group and in colon carcinoma cell group treated with PDTC. Treatment with the chemopreventive compounds 5-Fu and PDTC resulted in different responses in the effects of anti-proliferation and induced apoptosis of colon carcinoma cells. There was no significant difference in apoptosis between NGX6-transfected HT-29 cell line with 5-Fu and the cells in the control group. NGX6 gene enhanced the effect of 5-Fu on the proliferation and apoptosis of colon carcinoma cells. Conclusion： NGX6 gene can induce apoptosis and inhibit the proliferation of colon carcinoma cells. NGX6 gene can enhance the effect of 5-Fu on the proliferation and apoptosis of colon carcinoma cells through NF-κB pathway.