光动力对NHE1表达的影响及联合替莫唑胺抗鼠移植胶质瘤的相关研究

Photodynamic therapy (PDT) is an effective local target technology for treatment of gliomas. Due to parts of the glioma with characteristics of invasion and distant migration, the long-term curative effect of glioma is poor. Therefore, other kinds of treatments are used to assist in controlling the disease. Sodium hydrogen exchanger 1 (NHE1) is a kind of functional membrane transporters of the glioma cells. After activation, NHE1 can adversely affect the killing effects of chemotherapy drug Temozolomide on tumor cells, promote the invasion and migration, and inhibit apoptosis of glioma cells. Because PDT can damage the membrane structure itself and the mitochondria which supply energy for functional proteins, it may inhibit NHE1 function and antagonize TMZ resistance. So this study uses immunohistochemical, laser confocal microscope and flow cytometry, western blot and other advanced technology and methods, through the in vivo and in vitro experiments to detect the effect on expression of NHE1 and its activity after PDT, to detect the change of H+,Ca2+, MMP-2, MMP-9，caspase-3, to observe the synergy of photodynamic therapy and TMZ. This study is expected to establish experiment foundation of combined treatment of PDT and TMZ for glioma, and to explore an effective way to the comprehensive treatment for glioma .

光动力治疗是一种有效抑制脑胶质瘤的局部靶向治疗技术，但由于部分脑胶质瘤具有侵袭和远处迁移的特性，导致光动力治疗胶质瘤的远期疗效不佳，需辅助其它疗法来提高疗效。Na+/H+交换体-1（NHE1）是肿瘤细胞中较为活跃的功能蛋白，其活化后可以拮抗化疗药物替莫唑胺对肿瘤细胞的杀伤作用，促进胶质瘤细胞的侵袭和迁移，抑制细胞的凋亡。由于光动力作用对膜性结构本身及维系功能蛋白所需能量的线粒体系统的特异性损伤，有望抑制NHE1功能，拮抗替莫唑胺耐药现象，因而本研究应用免疫组化、激光共聚焦显微镜、流式细胞仪、western-blot等先进技术与方法，通过体内实验和体外实验检测光动力疗法对NHE1的表达及其活性的影响，检测H+、Ca2+、MMP-2、MMP-9、caspase-3的变化，观察光动力治疗和替莫唑胺的协同作用；为光动力与替莫唑胺联合抗脑胶质瘤奠定实验基础，探讨综合治疗脑胶质瘤的有效途径。

光动力治疗（photodynamic therapy,PDT）是一种利用特定波长的激发光激活蓄积在肿瘤组织中、无细胞毒性的光敏剂，在局部诱导发生光化学反应并产生强氧化性物质，从而靶向杀伤肿瘤的新技术，能有效抑制脑胶质瘤的生长。脑胶质瘤侵袭和远处迁移的特性可能与替莫唑胺治疗耐药有关。研究表明Na+/H+交换体-1（NHE1）是肿瘤细胞中较为活跃的功能膜蛋白，NHE1的活化可以拮抗化疗药物替莫唑胺对肿瘤细胞的杀伤作用，促进胶质瘤细胞的侵袭和迁移，抑制细胞的凋亡。PDT治疗主要通过靶向细胞膜性结构和线粒体发挥作用，可能通过损伤膜蛋白以及破坏能量供应链来抑制NHE1功能，拮抗胶质瘤的替莫唑胺耐药现象，增强替莫唑胺脑胶质瘤对的疗效。本研究应用免疫组化、激光共聚焦、流式细胞术、western-blot等多种技术方法，首先在体内外实验中验证了NHE-1可通过促进H+外排，使脑胶质瘤对替莫唑胺耐药以及促进肿瘤细胞在替莫唑胺的治疗中存活；然后检验了光动力疗法下调NHE1表达的作用以及联合替莫唑胺对胶质瘤侵袭、迁移、凋亡等表型的影响及相关作用机制，为光动力与替莫唑胺联合抗脑胶质瘤奠定实验基础，也为脑胶质瘤的综合治疗提供了新的技术方法。