M2型TAM通过HEXB调控胶质瘤糖酵解的机制研究

Identifying the important components of tumor microenvironment and exploring their regulatory mechanisms are the important topics in current cancer research. Tumor-associated macrophages (TAM)s are the most abundant non-tumor cells within glioma tissues. Most of TAMs are polarized into oncogenic M2 subtype. In previous study, we found that HEXB forms a malignant positive feedback loop between glioma cells and TAMs. HEXB facilitates glioma malignancy by repressing Hippo signaling and activating glycolysis. Here, we propose a project of "The mechanism of M2 TAM activating glioma glycolysis by HEXB". The project will interfere HEXB in the co-culture system to detect the change of glioma glycolysis, and explore whether M2 TAM regulates the glycolytic status of glioma cells through HEXB. The relationship between Hippo signaling and glycolytic status will be studied under HEXB intervention to clarify whether HEXB regulates glycolysis through Hippo signaling. We will also explore the binding sits between HEXB and ILK, a key upstream repressor of Hippo pathway. Their regulatory relationship will be fully investigated to clarify the mechanism of HEXB in suppressing Hippo pathway and facilitating glioma glycolysis. Taken together, this project will explore the interaction between tumor microenvironment and metabolic reprogramming, and try to elaborate the oncogenic mechanism of HEXB in glioma.

识别肿瘤微环境的重要构成并解析其中调控机制是当前肿瘤研究的重要课题。肿瘤相关巨噬细胞(TAM)是胶质瘤组织中最丰富的非肿瘤细胞，并大多极化为M2型发挥促癌作用。申请人前期发现HEXB参与构成胶质瘤细胞与TAM恶性正反馈环路，并通过抑制Hippo信号加速胶质瘤细胞糖酵解，因此提出“M2型TAM通过HEXB调控胶质瘤糖酵解的机制研究”。项目将在共培养体系中干预HEXB，检测胶质瘤糖酵解变化，探究M2型TAM是否依赖HEXB调节胶质瘤糖酵解过程；运用体内外实验平台，研究HEXB干预下Hippo通路与细胞糖酵解之间的作用关系，明确HEXB是否通过抑制Hippo信号发挥糖酵解促进作用；应用蛋白截短/突变技术，确定HEXB与Hippo信号上游抑制分子ILK的结合位点，并深入研究HEXB稳定ILK调控Hippo信号的分子机制。本项目将在肿瘤微环境与代谢重编程交叉领域进行有益探索，完善HEXB作用机制。

肿瘤是肿瘤细胞与其微环境通过复杂的交互调控网络构成的“命运共同体”，识别肿瘤微环境中的重要构成并解析关键调控枢纽的作用机制是当前肿瘤研究的重要课题。胶质瘤微环境中肿瘤相关巨噬细胞（TAM）含量最为丰富，加速肿瘤细胞增殖，促进肿瘤细胞侵袭，参与肿瘤血管新生等方式助力胶质瘤发生发展，但是关于M2型TAM对胶质瘤细胞代谢状态的调控仍存在大量未知。在本项目研究中，我们通过构建共培养模型证实了HEXB在M2型TAM调控胶质瘤糖酵解过程中的促进作用，应用蛋白质免疫沉淀与蛋白截短突变技术确定HEXB与Hippo信号上游ILK的结合位点，通过阻断蛋白水解、溶酶体、泛素化修饰等方法明确了外源性HEXB通过ILK调控Hippo信号通路以及细胞糖酵解的分子机制。依托本项目，相关研究成果成功在Neuro-oncology等高水平期刊发表，并申请发明专利及软件著作权授权各11项。本项目研究的重要意义在于从肿瘤与肿瘤微环境“命运共同体”视角出发，探索肿瘤微环境与肿瘤代谢重编程的密切关系，解析HEXB调控胶质瘤糖代谢重编程的恶性作用及相关分子机制，为将HEXB确立为新的胶质瘤生物标记物与治疗靶点提供理论依据。