基于GLUT1靶点的黄连素抑制肿瘤生长的机制研究

The GLUT1-mediated Glucose Transportplays a primary role intumor cell energy metabolism.It is currently deficient that tumor therapy drug is developed aiming inhibition of GLUT1 function.The preliminary work showsthat: berberine, a main active ingredient in Chinese medicine, with its berberine derivatives, can effectively inhibit the growth of tumor cells, affecting the interaction between GLUT1 and other proteins and down-regulating the expression of GLUT1. Furthermore, the experimentsindicatein vitrothat berberine can bind to the C-terminal region of GLUT1. Therefore, we intends to interpret that the mechanism between GLUT1 and berberine and its derivatives. We illustrate that berberine binds to the GLUT1 C-terminal region, causing the conformational change of GLUT1, which promotes Ubc9-mediated sumo-modification of GLUT1, causing the GLUT1 degradation via lysosome pathway; and, on the other hand, the combine inhibits the GIPC-mediated membrane translocation of GLUT1, resulting in the intracellular retention of GLUT1, and repress the GLUT1 glucose transporter function, thereby the growth of tumor cells is blocked and energy source is inhibited. The project illuminates the structure-activity relationship, paving the way for the theoretical basis for developing new strategies and the development of Chinese medicine.

葡萄糖转运体1（GLUT1）介导的葡萄糖转运是肿瘤细胞能量代谢的重要环节，目前尚缺乏靶向抑制GLUT1功能的抗肿瘤药物。本组前期工作显示：黄连素以及人工改造的黄连素衍生物，表现出显著抗肿瘤效应，并影响GLUT1与其它蛋白的相互作用并下调其蛋白表达水平；体外结合室验提示黄连素可以和GLUT1蛋白的C末端结合。本项目拟通过化学合成获得黄连素及其衍生物，从药物构效关系与蛋白质结构和功能的角度，阐释黄连素与GLUT1 蛋白作用机制，解释其抗肿瘤效应。证实黄连素与蛋白C末端结合，导致的蛋白空间构象改变，促进GLUT1的sumo化修饰，促进 GLUT1的溶酶体途径降解；还可抑制GLUT1膜转位过程，导致GLUT1在细胞内的滞留，进而抑制GLUT1的葡萄糖转运功能，阻断肿瘤细胞能量来源进而抑制肿瘤细胞的生长。本项目对阐明黄连素构效关系、为肿瘤的综合治疗提供新策略，对传统中药开发应用奠定理论基础。

项目执行期，葡萄糖转运体1（GLUT1）介导的葡萄糖转运是肿瘤细胞能量代谢的重要环节，目前缺乏靶向抑制GLUT1功能的抗肿瘤药物。项目组围绕黄连素与GLUT1蛋白及信号通路，本课题组开展了较细致全面的研究：我们成功获得三种黄连素衍生物；黄连素以及人工改造的黄连素衍生物，表现出显著抗肿瘤效应，并影响GLUT1与其它蛋白的相互作用并下调其蛋白表达水平；体外结合室验提示黄连素可以和GLUT1蛋白的C末端结合。本项目通过化学合成获得黄连素及其衍生物，从药物构效关系与蛋白质结构和功能的角度，阐释黄连素与GLUT1 蛋白作用机制，解释其抗肿瘤效应。证实黄连素与蛋白C末端结合，导致的蛋白空间构象改变，黄连素可以改变GLUT1在细胞内的分布与定位，影响GLUT1蛋白的分泌，抑制葡萄糖转运功能，阻断肿瘤细胞能量来源进而抑制肿瘤细胞的生长。获得了黄连素通过GLUT1蛋白靶向调节肿瘤细胞增殖转移机制的大量数据；黄连素与GLUT1胞外段互作的研究也取得了较好的结果。本项目对阐明黄连素构效关系、为肿瘤的综合治疗提供新策略，对传统中药开发应用奠定理论基础。