PI_3 K-Akt信号通路阻抑对结肠癌细胞LS-174T顺铂耐药逆转机制的研究
Effects of blocking PI_3K-Akt signal pathway in reversion of cisplatin resistance in colon adenocarcinoma cell line
杨玉捷 1孟辉 2杨国嵘 3薛永杰 3郁蓉 3贺雪娇 3罗菲 3惠玲 4张方信1
作者信息
- 1. 兰州军区总医院消化科,甘肃,兰州730050
- 2. 兰州军区总医院胸外科,甘肃,兰州730050
- 3. 解放军第一医院病理科,甘肃兰州730030
- 4. 兰州军区总医院医学实验中心,甘肃,兰州730050
- 折叠
摘要
目的:观察抑制磷脂酰肌醇3激酶和(或)蛋白激酶B(PI_3K-Akt)信号通路对顺铂耐药结肠癌细胞株LS-174T细胞核中Y-Box结合蛋白1(Y-Box binding protein-1,YB-1)的活性的影响及肿瘤细胞顺铂耐药性的改变.方法:采用顺铂(eisplatin,DDP)药物浓度递增法、间歇性作用的体外诱导法建立人结肠癌的顺铂耐药细胞系LS-174T/DDP,药物Ly294002阻断PI_3K-Akt信号通路传导后,采用Western Blot方法检测耐药肿瘤细胞磷酸化Akt表达水平,电泳迁移改变分析(EMSA)方法检测其核中转录因子YB-1活性的改变,MTT检测DDP对细胞增殖的抑制率,流式细胞仪检测细胞凋亡.结果:阻断PI_3K-Akt信号通路后,顺铂耐药细胞株中磷酸化Akt蛋白表达水平显著下降,同时其细胞核中VB-1的活性明显降低,且细胞的生长抑制率及细胞凋亡率均明显升高(P<O.01).结论:阻断PI_3K-Akt信号通路能够提高顺铂耐药细胞株对顺铂的敏感性,PI_3K-Akt信号通路可能通过激活YB-1在肿瘤顺铂耐药机制中发挥重要作用.
Abstract
AIM: To evaluate whether Ly294002, suppressing phosphatidylinositol 3 kinase PI_3 K/Akt survival signaling pathway, can affect the level of YB-1 activity in the nuclei of acquired cisplatin-resistant colon adenocarcinoma cell line and subsequently restore the sensitivity of acquired cisplatin-resistant colon adenocarcinoma cell line to cisplatin (DDP). METHODS:A LS-174T cell line resistant to cisplatin was successfully established by exposing cells to increasing cisplatin concentrations ranging from 0.1 to 0.8 mg/L on an intermittent dosage schedule. The cisplatin resistant colon adenocarcinoma cell line was treated with Ly294002. The alteration of phosphated Akt (p-Akt) protein level was examined by Western blotting and intranuclear YB-1 transcriptional activity was examined by electrophoretic mobility shift assays ( EMSA ). The inhibition rates were determined by MTT assay. Cell apoptosis was evaluated by flow cytometry. RESULTS: After the inhibition of PI_3K/Akt signaling, Western blotting analysis revealed a dramatic decrease of p-Akt expression and this was correlated with decreased nuclear YB-1 activity in cisplatin-resistant cell line. Meanwhile, the apoptosis rate and cell growth inhibition rate were also increased in comparison with control cultures(P<0. 0H. CONCLUSION. The inhibition of PI_3K/Akt signal pathway may sensitize cisplatin-resistant cell line to DDP in vitro. PI_3, K/Akt pathway on the activation of YB-1 may play an important role in this process.
关键词
PI_3K-Akt信号通路/Y-Box结合蛋白1/人结肠癌/获得性顺铂耐药Key words
PI_3 K/Akt pathway/nuclear YB-1/human colon carcinoma/acquired cisplatin resistance引用本文复制引用
出版年
2009
NETL
NSTL
万方数据