藤黄酸通过抑制GLUT-3/AKT信号通路增强神经胶质瘤U251细胞对替 莫唑胺的敏感性

目的：探索藤黄酸是否能够增强神经胶质瘤U251细胞对替莫唑胺的敏感性，并进一步探索其增敏机制。方法： 体 外培养U251细胞，并分成空白对照组、藤黄酸单独处理组、替莫唑胺单独处理组和联合处理组；利用CCK-8实验检测各组细胞存 活率，利用流式细胞术检测细胞凋亡情况和 ROS 水平变化情况，利用Western blotting 实验检测相关蛋白表达量变化情况。 结果: CCK-8法实验中，四组细胞处理24 h后存活率依次为（98.65±3.68） %、（93.58±2.47） %、（66.81±2.39） %和（38.65±4.13） %， 可 以看出联合处理组能够大幅提高对替莫唑胺对U251细胞增殖的抑制作用（P<0.01）；联合处理组U251细胞凋亡比例为（61.43± 2.58） %，与替莫唑胺单独处理组的（26.68±1.82） %相比明显增加（P<0.01）；藤黄酸和替莫唑胺共同处理后能够上调U251细胞 ROS水平和降低GLUT-3和p-AKT的表达，抑制GLUT-3/AKT信号通路（P<0.05或P<0.01）。结论: 藤黄酸与替莫唑胺联用能够 通过上调U251细胞中的ROS水平、抑制GLUT-3和AKT信号通路而增强U251细胞对替莫唑胺的敏感性。

Gambogic acid enhances sensitivity of glioma U251 cells to temozolomide by inhibiting GLUT-3/AKT signaling pathway

Objective: To explore whether gambogic acid can enhance the sensitivity of glioma U251 cells to temozolomide and further explore its mechanism. Methods: U251 cells were cultured in vitro and divided into blank control group, gambogic acid treatment group, temozolomide alone treatment group and combined treatment group. The cells survival rates of cells in each group was detected by CCK-8 assay. Flow cytometry was used to detect cell apoptosis and changes in ROS level. Western blotting was used to detect the changes in protein expressions. Results: CCK-8 results showed that the cells survival rates of the four groups after treatment for 24 h were (98.65±3.68)%, (93.58±2.47)%, (66.81±2.39)% and (38.65±4.13)%, respectively. It can be seen that the combined treatment could significantly increase the inhibitory effect of temozolomide on U251 cells. The proportion of apoptotic U251 cells in the combined treatment group was (61.43±2.58)%, which was significantly higher than that of (26.68±1.82)% in the temozolomide-treated group. Combined treatment of gambogic acid and temozolomide could up-regulate ROS level in U251 cells, reduce the expressions of GLUT-3 and p-AKT, and inhibit the GLUT-3/AKT signaling pathway. Conclusion: Gambogic acid combined with temozolomide can enhance the sensitivity of U251 cells to temozolomide by up-regulating ROS level and inhibiting GLUT-3/AKT signaling pathway in U251 cells, and provides a theoretical basis for the application of gambogic acid in the treatment of glioma.