温郁金中新二萜类化合物C诱导人结肠腺癌SW620细胞凋亡的相关通路研究

Apoptosis of human colon adenocarcinoma cell line SW620 induced by diterpenoid C from Radix Curcumae and its related pathways

目的探讨温郁金二萜类化合物C诱导人结肠腺癌SW620细胞凋亡的作用机制。方法以5-氟脲嘧啶(5-Flu-orouracil,5-FU)为阳性对照药物;采用噻唑蓝(methyl thia-zolyl tetrazolium,MTT)还原法检测化合物C和5-FU对SW620细胞增殖的影响;用流式细胞术(flow cytometry,FCM)检测两种药物诱导细胞凋亡的情况;用Western blot法检测化合物C作用后,细胞中ERK、p-ERK、JNK、p-JNK、p38、p-p38及caspase-3蛋白水平的变化。结果化合物C能抑制SW620细胞的增殖活性,并明显诱导细胞凋亡,其抑制率和凋亡率呈时间-浓度依赖性,且都明显高于5-FU组;其24、48和72 h的IC50分别为29.75、15.91和6.55 mg.L-1;化合物C能浓度依赖性地下调细胞中ERK、JNK、p38及其相应磷酸化蛋白的水平,并刺激caspase-3的蛋白表达。结论温郁金二萜类化合物C能抑制人结肠腺癌SW620细胞的生长并诱导凋亡,其作用机制可能与抑制MAPK信号转导通路、活化caspase-3有关。

Aim To study the apoptotic effect of the new diterpenoid C from Radix Curcumae on human colon adenovarcinama SW620 cells and its underlying mechanisms.Methods The effect of diterpenoid C on cell proliferation was assessed by MTT assay,the cell apoptosis induced by diterpenoid C was determined by flow cytometry,and the expression level of ERK,p-ERK,JNK,p-JNK,p38 MAPK,p-p38 MAPK,caspase-3 was detected by Western blot analysis.Results Diterpenoid C inhibited the cell proliferation and induced apoptosis in dose-and time-dependent manners,which was significantly more potent than 5-Fluorouracil.The median inhibitory concentration（IC50） at 24,48,and 72 h were 28.31,15.58,and 6.14 mg·L-1,respectively.The expression level of ERK,JNK,p38 and their corresponding phosphorylation products was reduced by diterpenoid C in a dose-dependent manner,while the level of caspase-3 was increased.Conclusion Diterpenoid C inhibits proliferation and induces apoptosis of SW620 cells by suppressing MAPK signaling pathway and inducing apoptotic factor caspase-3.