蛇床子素对TRAIL抗乳腺癌活性的影响及其作用机制

Effect of Osthole on the Anti-breast Cancer Activity of TRAIL and Its Mechanism

关键词:  蛇床子素  TRAIL  乳腺癌  caspase-8  凋亡

Key words:  osthole  TRAIL  breast cancer  caspase-8  apoptosis

摘要:

目的 探讨中药活性成分蛇床子素对抗肿瘤药物TRAIL抗乳腺癌活性的影响并研究其机制。方法 用蛇床子素联合TRAIL体外治疗乳腺癌细胞系BT-20，MTT法检测肿瘤细胞的细胞活力，Annexin V/PI染色检测肿瘤细胞的凋亡，免疫共沉淀法检测RIP1-FADD-caspase-8复合物的形成。western blot法检测BT-20细胞caspase-8的活化及蛇床子素对BT-20细胞cIAP2蛋白表达的影响。结果 联用蛇床子素显著提高TRAIL对BT-20细胞活力的抑制率和凋亡诱导活性。免疫共沉淀及western blot结果发现联合蛇床子素后，TRAIL治疗的BT-20细胞内的RIP1-FADD-caspase-8复合物水平及caspase-8的活化程度显著提高。Western blot结果发现蛇床子素对BT-20细胞内的cIAP2蛋白表达有抑制作用。在BT-20细胞中转染cIAP2表达质粒后，蛇床子素对TRAIL抗肿瘤活性的促进作用受到抑制。结论 蛇床子素通过促进死亡受体复合物的形成增强TRAIL对乳腺癌细胞的凋亡诱导效应。

Abstract:

OBJECTIVE To investigate the effect of osthole on the anti-breast cancer activity of TRAIL and study its mechanism. METHODS After the BT-20 cells were treated with TRAIL combined with osthole, the cell viability, cell apoptosis, and the formation of RIP1-FADD-caspase-8 complex were detected by MTT assay, Annexin Ⅴ/PI staining, and co-immunoprecipitation, respectively. The activation of caspase-8 and the expression of cIAP2 in BT-20 cells were evaluated by western blot assay. RESULTS Addition of osthole significantly enhanced the cell viability inhibition rate and apoptosis inducing activity in BT-20 cells treated with TRAIL. The results of co-immunoprecipitation and western blot indicated that the formation of RIP1-FADD-caspase-8 complex and the activation of caspase-8 in TRAIL-treated BT-20 cells were significantly increased due to the combination of osthole. The results of western blot assay demonstrated that the expression of cIAP2 could be significantly inhibited due to the osthole treatment. Moreover, the transfection of cIAP2 vector abolished the promotion of osthole on TRAIL-induced cell death in BT-20 cells. CONCLUSION osthole promotes TRAIL-induced apoptosis by the formation of RIP1-FADD-caspase-8 complex in breast cancer.