槲皮素对人结肠癌HT-29细胞凋亡的影响

目的 研究槲皮素对人结肠癌HT-29细胞凋亡的影响,并探讨其对肿瘤坏死因子受体相关因子6(tumor necrosis factor receptor factor 6,Traf6)/转化生长因子β激活酶1(transforming growth factor-βactivated kinase-1,TAK1)信号通路的调控作用.方法 将细胞按随机数字表法分为对照组、16μg/ml槲皮素组、Traf6抑制剂组、16μg/ml槲皮素+Traf6抑制剂组,对照组常规培养,其余各组加入16μg/ml槲皮素和/或Traf6抑制剂20 nmol/L进行干预.培养24 h,采用流式细胞仪检测各组细胞凋亡率,采用免疫印迹法检测Traf6/TAK1信号通路蛋白及caspase-3、Bcl-2相关X蛋白(Bcl-2 associated X protein,Bax)及Bcl-2表达,采用RT-PCR技术检测Traf6 mRNA表达.结果 与16μg/ml槲皮素组比较,16μg/ml槲皮素+Traf6抑制剂组Traf6(0.59±0.03)比(0.96±0.04)]、p-TAK1(0.43±0.02)比(0.72±0.04)]、caspase-3(0.59±0.03)比(0.70±0.04)]、Bax(0.48±0.03)比(0.67±0.04)]表达降低,Bcl-2(0.54±0.03)比(0.44±0.02)]表达升高(P<0.05),Traf6 mRNA(0.38±0.24)比(0.82±0.08)]表达降低(P<0.05).结论 槲皮素可诱导人结肠癌HT-29细胞凋亡,其作用机制可能与激活Traf6/TAK1信号通路有关.

Induced apoptosis by quercetin in human colon cancer HT-29 cells through Traf6/TAK1 signaling pathway

Objective To study the effect of quercetin on the apoptosis of human colon cancer HT-29 cells and observe the possible mechanism.Methods Human colon cancer HT-29 cells were cultured in vitro and divided into four groups, including the control group, the 16μg/ml quercetin group, the Traf6 inhibitor group and the 16μg/ml quercetin + inhibitor group. The cells in control group were cultured with complete medium and other groups were treated with quercetin or/and Traf6 inhibitor. Flow cytometry was used to observe the impact of quercetin on the apoptosis of HT-29 cells; Western Blot technology was used to detect the expression levels of Traf6, TAK1, p-TAK1, caspase-3, Bax and Bcl-2; RT-PCR was used to investigate the expression level of Traf6 mRNA after treating for 24 h.Results Compared with the 16μg/ml quercetin group, the expression levels of Traf6 (0.59 ± 0.03 vs. 0.96 ± 0.04), p-TAK1 (0.43 ± 0.02vs. 0.72 ± 0.04), caspase-3 (0.59 ± 0.03vs. 0.70 ± 0.04), and Bax (0.48 ± 0.03vs.0.67 ± 0.04) were significantly decreased in 16μg/ml quercetin + inhibitor group(P<0.05). while the expression levels of Bcl-2 (0.54 ± 0.03vs. 0.44 ± 0.02) was significantly increased (P<0.05).Conclusions Quercetin can induce the apoptosis of human colon cancer HT-29 cells and the effective mechanism may relate to the activation of Traf6/TAK1 signaling pathway.