Han Liping, Zhang Yongfei, Liu Shuai, Zhao Qingwei, Liang Xianhong, Ma Zhiguo, Gupta Prakash K, Zhao Miaoqing, Wang Aihua
Department of Neurology, Qianfoshan Hospital Affiliated to Shandong University, Jinan, P.R. China.
Department of Neurology, Shandong Police Hospital, Jinan, P.R. China.
Oncotarget. 2017 Nov 21;8(64):107730-107743. doi: 10.18632/oncotarget.22594. eCollection 2017 Dec 8.
This study aimed to investigate whether ubenimex could work as an anti-tumor drug alone in glioma cells and figure out the underlying potential mechanisms. Ubenimex is widely used as an adjunct therapy in multiple solid cancers. However, it is rarely used to treat glioblastoma. The function of ubenimex in enhancing JQ1 treatment sensitivity of glioma cells by blocking autophagic degradation of HEXIM1 was previously studied. However, the detailed mechanism of autophagy regulation by ubenimex remains unclear. The U87 and U251 cell lines were treated with different doses of ubenimex. Cell viability was measured by using the WST-8 assay. Cell death was assessed using trypan blue staining and flow cytometry. The migration and invasive ability of glioma cells were examined by transwell migration/invasion assay. LC3-GFP-RFP was used to measure autophagic flux. Protein expression was assessed by Western blot analysis. Autophagosomes were evaluated using the transmission electron microscopy. Moreover, cell cycle arrest (PI Staining) was measured by flow cytometry. Results revealed that ubenimex inhibited cell proliferation as well as migration/invasion in glioma cells. Besides, ubenimex increased glioma cell death via autophagic flux inhibition. Meanwhile, ubenimex induced G2/M phase arrest and apoptosis, and this effect was accompanied by the decreased levels of p-Akt, indicating the role of ubenimex in the regulation of glioma cell proliferation and metastasis. To sum up, this study concluded that ubenimex could work as an anti-tumor drug alone in the glioma cells via inhibiting autophagic flux and inducing G2/M arrest as well as apoptosis.
本研究旨在探讨乌苯美司能否单独作为一种抗胶质瘤细胞的抗肿瘤药物，并找出其潜在的作用机制。乌苯美司在多种实体癌中广泛用作辅助治疗药物。然而，它很少用于治疗胶质母细胞瘤。此前曾研究过乌苯美司通过阻断HEXIM1的自噬降解来增强胶质瘤细胞对JQ1治疗的敏感性的作用。然而，乌苯美司调节自噬的详细机制仍不清楚。用不同剂量的乌苯美司处理U87和U251细胞系。使用WST-8法测定细胞活力。使用台盼蓝染色和流式细胞术评估细胞死亡情况。通过Transwell迁移/侵袭试验检测胶质瘤细胞的迁移和侵袭能力。使用LC3-GFP-RFP来测量自噬通量。通过蛋白质印迹分析评估蛋白质表达。使用透射电子显微镜评估自噬体。此外，通过流式细胞术测量细胞周期阻滞（PI染色）。结果显示，乌苯美司抑制胶质瘤细胞的增殖以及迁移/侵袭。此外，乌苯美司通过抑制自噬通量增加胶质瘤细胞死亡。同时，乌苯美司诱导G2/M期阻滞和凋亡，并且这种作用伴随着p-Akt水平的降低，表明乌苯美司在调节胶质瘤细胞增殖和转移中的作用。综上所述，本研究得出结论，乌苯美司可通过抑制自噬通量、诱导G2/M期阻滞以及凋亡单独作为一种抗胶质瘤细胞的抗肿瘤药物。
