
藤黄酸增强人胃癌SGC7901/DDP细胞对顺铂的敏感性
Enhancing effect of gambogic acid on the sensibility of human gastric carcinoma SGC7901/DDP cells to cisplatin
目的 探讨藤黄酸(GA)对人胃癌SGC7901/DDP细胞顺铂敏感性的影响及其分子机制。 方法 采用顺铂(DDP)浓度梯度递增法构建人胃癌顺铂耐药株SGC7901/DDP细胞,采用细胞计数盒-8(CCK-8)法检测藤黄酸和顺铂对SGC7901/DDP细胞的毒性作用,采用Chou-Talalay中效分析法定量评价藤黄酸和顺铂的联合作用效果,采用流式细胞术检测细胞凋亡,采用Western blotting方法检测Bcl-2、Bax、Survivin、多药耐药相关蛋白2(MRP2)、磷酸化氨基末端蛋白激酶(p-JNK)(Thr183/Tyr185)和JNK的蛋白水平。 结果 藤黄酸与顺铂各自单独作用48 h的IC50分别为2.94 μmmol/L和39.76 μmmol/L;当抑制率超过20%时,两者联合应用呈协同效应;藤黄酸可协同增强顺铂诱导的细胞凋亡(P<0.05),下调Survivin和MRP2蛋白水平(P<0.05),上调Bax蛋白水平(P<0.05),抑制JNK磷酸化(P<0.05);JNK特异性抑制剂SP600125可下调MRP2蛋白水平(P<0.05)。 结论 藤黄酸可增强人胃癌SGC7901/DDP细胞对顺铂的敏感性,这可能与藤黄酸通过抑制JNK信号通路下调MRP2蛋白表达,以及上调Bax蛋白表达和下调Survivin蛋白表达有关。
Objective The aim of this study is to investigate the effect of gambogic acid (GA) on the sensibility of human gastric carcinoma SGC7901/DDP cells to cisplatin (DDP) and its possible mechanism. Methods The drug-resistant SGC7901/DDP cells were established by stepwise exposure to DDP. CCK-8 assay was employed to detect the cytotoxic effect of GA and DDP on SGC7901/DDP cells, and the combined effect of GA and DDP was analyzed by Chou-Talalay method . The cell apoptosis was studied by flow cytometry. Western blotting was performed to detect the protein levels of Bcl-2, Bax, Survivin, multidrug resistance-associated protein 2 (MRP2), phosphorylated c-Jun N-terminal kinase (p-JNK) (Thr183/Tyr185) and JNK. Results The IC50 values of GA and DDP were 2.94 μmol/L and 39.76 μmol/L after 48 hours treatment respectively, and the combined both drugs improved the antitumor effects on SGC7901/DDP cells. GA enhanced cisplatin-induced apoptosis (P<0.05), down-regulated Survivin and MRP2 and up-regulated Bax at the protein level (P<0.05), and inhibited phosphorylation of JNK in SGC7901/DDP cells (P<0.05). SP600125, a specific inhibitor of JNK, declined the protein level of MRP2 (P<0.05). Conclusion GA may enhance the sensibility of SGC7901/DDP cells to cisplatin by down-regulating MRP2 as a result of inactivation of the JNK signaling pathway, and up-regulating Bax and down-regulating Survivin.
藤黄酸 / 胃癌 / 顺铂 / 耐药性 / SGC7901/DDP细胞 / 免疫印迹法 / 人
Gambogic acid / Gastric carcinoma / Cisplatin / Drug resistance / SGC7901/DDP cell / Western blotting / Human
/
〈 |
|
〉 |