RAD51AP1介导的DNA损伤修复在EGFRvIII胶质瘤耐药中的临床与机制研究

EGFRvIII mutation is one of the most typical molecular alterations in glioma. By analyzing single-cell RNA sequencing, RNA sequencing from mouse model and CRISPR/Cas9 gene editing library, we revealed that the EGFRvIII mutation-related genes were mainly enriched in the DNA damage repair pathway. RAD51AP1, which is a key regulator in homologous recombination, was the most significant candidate. The expression of RAD51AP1 was correlated with WHO grade and malignant phenotype, and served as an independent prognostic factor of glioma. Based on the above results, we proposed the research of " the clinical and functional investigations of RAD51AP1 in EGFRvIII-induced DNA damage response and temozolomide resistance". We aim to study the biological functions of RAD51AP1 and its effect on chemotherapeutic resistance. Further, we will explore the epigenetic and transcriptional regulation of EGFRvIII on RAD51AP1 by H3K27ac and SOX9. Finally, we will use cell-derived xenografts (CDXs) model to verify the regulatory relationship between EGFRvIII and RAD51AP1, and to explore the therapeutic value of RAD51AP1 targeting in EGFRvIII mutant gliomas. This ressearch will aid in revealing the molecular mechanism by which EGFRvIII regulates temozolomide resistance, providing a new strategy for glioma targeted therapy and chemotherapy sensitization.

EGFRvIII突变是胶质瘤中经典的分子变异。申请人前期通过单细胞测序、裸鼠移植瘤测序及CRISPR/Cas9基因编辑文库筛选，发现EGFRvIII突变相关基因显著富集在DNA损伤修复相关信号通路。其中，RAD51AP1改变最为明显，其表达水平与肿瘤级别及恶性表型相关，是胶质瘤独立预后因子。基于上述结果，申请人提出“RAD51AP1介导的DNA损伤修复在EGFRvIII胶质瘤耐药中的临床与机制研究”这一课题，拟以大数据为基础，研究RAD51AP1的生物学功能及其对化疗抵抗的作用；明确EGFRvIII通过H3K27乙酰化表观修饰及SOX9转录调控促进RAD51AP1表达的机制；通过小鼠原位肿瘤模型验证上述调控关系，并探讨抑制RAD51AP1对EGFRvIII突变肿瘤的治疗价值。本项目将揭示EGFRvIII通过同源重组修复调控替莫唑胺化疗抵抗的分子机制，为胶质瘤靶向治疗和化疗增敏提供新策略。

胶质母细胞瘤是中枢神经系统最常见的原发性恶性肿瘤，其中EGFR胞外区的EGFRvIII突变是胶质母细胞瘤中经典的分子变异。申请人通过RNA测序、单细胞测序、裸鼠移植瘤测序及CRISPR/Cas9基因编辑文库筛选，发现EGFRvIII突变相关基因显著富集在DNA损伤修复相关信号通路。其中，RAD51AP1改变最为明显，其表达水平与肿瘤级别及恶性表型相关，是胶质瘤独立预后因子。基于上述结果，申请人提出“RAD51AP1介导的DNA损伤修复在EGFRvIII胶质瘤耐药中的临床与机制研究”这一课题。本课题研究了RAD51AP1的生物学功能及其对替莫唑胺化疗抵抗的作用；明确EGFRvIII通过H3K27乙酰化表观修饰及SOX9转录调控促进RAD51AP1表达的机制及对DNA损伤信号通路的作用；通过患者来源肿瘤细胞小鼠原位肿瘤模型验证上述调控关系，并探讨抑制RAD51AP1对EGFRvIII突变肿瘤的治疗价值。本项目揭示了EGFRvIII/RAD51AP1通过同源重组修复调控替莫唑胺化疗抵抗的分子机制，为胶质瘤靶向治疗和化疗增敏提供新策略。