Dai Li-Bo, Zhong Jiang-Tao, Shen Li-Fang, Zhou Shui-Hong, Lu Zhong-Jie, Bao Yang-Yang, Fan Jun
Department of Otolaryngology, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang, China.
Department of Radiotherapy, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang, China.
J Cell Mol Med. 2021 May 6. doi: 10.1111/jcmm.16450.
In this study, we investigated the ability of curcumin alone or in combination with GLUT1 siRNA to radiosensitize laryngeal carcinoma (LC) through the induction of autophagy. Protein levels in tumour tissues and LC cells were measured by immunohistochemistry and Western blotting. In vitro, cell proliferation, colony formation assays, cell death and autophagy were detected. A nude mouse xenograft model was established through the injection of Tu212 cells. We found that GLUT1 was highly expressed and negatively associated with autophagy-related proteins in LC and that curcumin suppressed radiation-mediated GLUT1 overexpression in Tu212 cells. Treatment with curcumin, GLUT1 siRNA, or the combination of the two promoted autophagy. Inhibition of autophagy using 6-amino-3-methypourine (3-MA) promoted apoptosis after irradiation or treatment of cells with curcumin and GLUT1 siRNA. 3-MA inhibited curcumin and GLUT1 siRNA-mediated non-apoptotic programmed cell death. The combination of curcumin, GLUT1 siRNA and 3-MA provided the strongest sensitization in vivo. We also found that autophagy induction after curcumin or GLUT1 siRNA treatment implicated in the AMP-activated protein kinase-mTOR-serine/threonine-protein kinase-Beclin1 signalling pathway. Irradiation primarily caused apoptosis, and when combined with curcumin and GLUT1 siRNA treatment, the increased radiosensitivity of LC occurred through the concurrent induction of apoptosis and autophagy.
在本研究中，我们研究了姜黄素单独或与葡萄糖转运蛋白1（GLUT1）小干扰RNA（siRNA）联合使用通过诱导自噬使喉癌（LC）放射增敏的能力。通过免疫组织化学和蛋白质印迹法检测肿瘤组织和LC细胞中的蛋白质水平。在体外，检测细胞增殖、集落形成试验、细胞死亡和自噬。通过注射Tu212细胞建立裸鼠异种移植模型。我们发现GLUT1在LC中高表达且与自噬相关蛋白呈负相关，并且姜黄素可抑制辐射介导的Tu212细胞中GLUT1的过表达。用姜黄素、GLUT1 siRNA或二者联合处理可促进自噬。使用6-氨基-3-甲基嘌呤（3-MA）抑制自噬可促进照射后或用姜黄素和GLUT1 siRNA处理细胞后的细胞凋亡。3-MA抑制姜黄素和GLUT1 siRNA介导的非凋亡程序性细胞死亡。姜黄素、GLUT1 siRNA和3-MA联合使用在体内具有最强的增敏作用。我们还发现，姜黄素或GLUT1 siRNA处理后诱导的自噬与AMP激活的蛋白激酶-雷帕霉素靶蛋白-丝氨酸/苏氨酸蛋白激酶-Beclin1信号通路有关。照射主要引起细胞凋亡，当与姜黄素和GLUT1 siRNA联合处理时，LC放射敏感性的增加是通过同时诱导细胞凋亡和自噬实现的。
