GP-EP

Epidermal growth factor receptor (EGFR) mutations are common in lung adenocarcinoma (LUAD). However, the lack of practical preclinical models has limited our understanding of how EGFR mutations reshape the tumor immune microenvironment. EGFRE19del/E19del; Trp53-/- (EP) cell lines were established from a genetically engineered mouse model (GEMM) harboring a human EGFR exon 19 deletion mutation. These cell lines were used to generate orthotopic tumors in both immunodeficient and immunocompetent mice. Drug sensitivity assays were performed to evaluate responses to Osimertinib. Multi-omics analyses, including transcriptomic and metabolic profiling, were conducted to compare EP tumors with KRAS-mutant models and human EGFR-mutant LUAD. EP cell lines formed tumors in both immunodeficient and immunocompetent mice and showed sensitivity to Osimertinib comparable to human EGFR-mutant cell lines. EP tumors further developed acquired resistance to EGFR-TKI therapy, accompanied by transcriptional reprogramming marked by enhanced epithelial-mesenchymal transition (EMT) and Wnt/β-catenin signaling. Multi-omics analysis revealed that EP tumors closely recapitulate the molecular features of human EGFR-mutant LUAD, while exhibiting distinct transcriptomic and metabolic profiles compared to KRAS-mutant models. Immune profiling demonstrated a suppressed adaptive immune response in EP tumors, including reduced infiltration of tissue-resident memory T cell and increased M2-like polarization of macrophage. This study presents a novel preclinical model that practically represents EGFR-mutant LUAD. Unlike traditional models relying on exogenous EGFR mutations, EP cells are endogenously driven by EGFR signaling and accurately reflect the immunosuppressive microenvironment observed in patients. This model provides a efficient platform for investigating mechanisms of immune evasion and for developing innovative therapeutic strategies.表皮生长因子受体（EGFR）突变在肺腺癌（LUAD）中十分常见。然而，实用临床前模型的匮乏，限制了我们对EGFR突变如何重塑肿瘤免疫微环境的认知。本研究从携带人EGFR外显子19缺失突变的基因工程小鼠模型（GEMM）中，成功构建了EGFRE19del/E19del；Trp53-/-（EP）细胞系。将该细胞系接种至免疫缺陷及免疫健全小鼠体内，均可成功构建原位肿瘤模型。通过药物敏感性检测，评估其对奥希替尼（Osimertinib）的应答情况。开展涵盖转录组学与代谢组学谱分析的多组学研究，对比EP肿瘤与KRAS突变模型及人EGFR突变型LUAD的差异。结果显示，EP细胞系在免疫缺陷及免疫健全小鼠体内均可成瘤，且对奥希替尼的敏感性与人EGFR突变细胞系相当。EP肿瘤可进一步对EGFR-TKI疗法产生获得性耐药，伴随以增强的上皮间质转化（EMT）及Wnt/β-连环蛋白信号通路为特征的转录重编程。多组学分析表明，EP肿瘤可高度复现人EGFR突变型LUAD的分子特征，且与KRAS突变模型相比，其转录组及代谢组谱存在显著差异。免疫谱分析显示，EP肿瘤中适应性免疫应答受到抑制，具体表现为组织驻留记忆T细胞（tissue-resident memory T cell）浸润减少，以及巨噬细胞向M2样表型极化的比例升高。本研究构建了一种可真实模拟EGFR突变型LUAD的新型临床前模型。与传统依赖外源性EGFR突变的模型不同，EP细胞由EGFR信号通路内源性驱动，可精准模拟患者体内观察到的免疫抑制微环境。该模型为探究肿瘤免疫逃逸机制及开发创新治疗策略提供了高效的研究平台。