Bostrycin作为肺癌分子靶向药物的体外研究

In vitro study of Bostrycin as a molecule target drug in lung cancer

目的观察海洋真菌新结构先导化合物Bostrycin对A549细胞增殖和凋亡的影响，并探讨其作用机制。方法A549细胞完全随机分为实验组和对照组，实验组用不同浓度不同作用时间的Bostzycin进行处理，而对照组未经Bostrycin处理。用MTT法检测A549细胞增殖率的变化；电镜、流式细胞术检测凋亡；实时定量PCR和免疫印迹法探讨其作用机制。结果Bostrycin浓度≥10μmol／L时对A549细胞增殖有明显的抑制作用，其24、48和72h的半数抑制浓度（IC50）分别为20，20、14．36和9．42μmol／L。Bostrycin干预后，电镜观察到A549细胞典型的凋亡形态；流式细胞术结果显示其G0／G1期比例升高、S期和G2／M期比例下降，凋亡率增加。实时定量PCR检测到微小RNA（miRNA）-638和miRNA-923的表达较对照组上调。免疫印迹结果显示p110ix、p-Akt蛋白表达量下降，p27蛋白表达量升高。结论Bostrycin对A549细胞增殖有显著抑制作用，该作用可能通过miRNA抑制磷脂酰肌醇3-激酶／蛋白激酶B（P13K／Akt）通路进行。

Objective To investigate the effect of the new-structure compound Bostrycin from marine fungi on the proliferation and apoptosis of lung cancer cell A549 in vitro, and to explore its mechanism. Methods A549 cells were complete randomly divided into treatment group and control group. A549 cells in treatment group were treated with different concentrations of Bostrycin for different time while cells in control group were not. The rate of proliferation of A549 cells before and after treatment was assessed with MTT method, Electron microscopy and flow cytometry were used to detect apoptosis of the cells. Real time PCR and Western blot were employed to explore the mechanism of Bostrycin. Results Bostrycin at a level of ≥ 10 μmol/L had a significant inhibitory effect on the proliferation of A549 cell, and the 24-, 48- and 72-hour ICs0 （inhibitory concentration of half） were 20.20, 14.36 and 9.42 μ mol/L, respectively. Following Bostrycin interference, typical apoptotic appearance of A549 ceils could be observed under electron microscope. Percentage increased for the cells at G0/G1 phase and decreased for the cells at S phase or G2/M phase with increased apoptotic rate as were revealed by flow cytometry. Signal up-regulation was detected with real time RT-PCR in both micro RNA-638 and micro RNA-923, and decreased expression of the proteins p110 α and p- Akt and increased expression of p27 protein were found by Western blot. Conclusions Bostrycin has significant inhibition on A549 cell proliferation possibly through suppression of PI3K/Akt pathway by micro RNAs.