Department of Pancreatic Cancer, Tianjin Medical University Cancer Institute and Hospital, National Clinical Research Center for Cancer; Key Laboratory of Cancer Prevention and Therapy, Tianjin's Clinical Research Center for Cancer, Tianjin, China.
Second Department of Breast Cancer, Tianjin Medical University Cancer Institute and Hospital, National Clinical Research Center for Cancer, Key Laboratory of Cancer Prevention and Therapy, Tianjin, China
J Immunother Cancer. 2024 Nov 14;12(11):e009636. doi: 10.1136/jitc-2024-009636.
Neoadjuvant therapy with trastuzumab, pertuzumab and paclitaxel (THP) has significantly improved the prognosis of patients with human epidermal growth factor receptor 2 (HER2) breast cancer (BC). However, there remains a subset of non-responsive patients. Thus, this study sought to identify key regulators of THP neoadjuvant therapy resistance and potential targets to sensitize sensitivity.
The Cancer Genome Atlas database, Gene Expression Omnibus and membrane protein database were used to identify the key regulator of THP neoadjuvant resistance. The biological functions and mechanisms of delta-like 4 proteins (DLL4) in THP therapy resistance were investigated in vitro and in vivo using the bioinformatic analysis, multiplex immunofluorescence, flow cytometry, sphere formation assays and chromatin immunoprecipitation, etc. Furthermore, DLL4-targeted chimeric antigen receptor (CAR)-T cells were established to sensitize THP therapy.
DLL4 was identified as a key target in THP neoadjuvant therapy resistance for HER2 BC. Mechanistically, DLL4 tumor cells exhibited enhanced stemness and resistance to the THP neoadjuvant chemotherapy. Additionally, soluble DLL4 can split away from tumor cells and diffuse into the stroma, where it can activate the Notch signaling pathway in neutrophils, inducing the formation and release of neutrophil extracellular traps (NETs) by regulating the transcription of MPO, PDIA4 and ELANE. This led to the exclusion of lymphocyte infiltration, thereby enhancing therapy resistance. What is more, we designed a DLL4-targeted CAR-T to eliminate DLL4 tumor cells and reverse the resistant status.
Our study revealed novel functions of DLL4 in cell stemness and immune infiltration, including NET formation and T cell exclusion, which collectively contributed to THP neoadjuvant therapy resistance in HER2 BC. Furthermore, we provided a CAR-T-based therapy to sensitize the THP neoadjuvant therapy.
曲妥珠单抗、帕妥珠单抗和紫杉醇（THP）新辅助治疗显著改善了人表皮生长因子受体 2（HER2）乳腺癌（BC）患者的预后。然而，仍有一部分患者对治疗无反应。因此，本研究旨在确定 THP 新辅助治疗耐药的关键调节因子和潜在的增敏靶点。
利用癌症基因组图谱数据库、基因表达综合数据库和膜蛋白数据库，鉴定 THP 新辅助耐药的关键调节因子。采用生物信息学分析、多重免疫荧光、流式细胞术、球体形成实验和染色质免疫沉淀等方法，研究 Delta-like 4 蛋白（DLL4）在 THP 治疗耐药中的生物学功能和机制。此外，还建立了 DLL4 靶向嵌合抗原受体（CAR）-T 细胞，以增敏 THP 治疗。
DLL4 被确定为 HER2 BC 中 THP 新辅助治疗耐药的关键靶点。机制上，DLL4 肿瘤细胞表现出增强的干性和对 THP 新辅助化疗的耐药性。此外，可溶性 DLL4 可以从肿瘤细胞上脱离并扩散到基质中，在基质中它可以通过调节 MPO、PDIA4 和 ELANE 的转录来激活中性粒细胞中的 Notch 信号通路，诱导中性粒细胞胞外陷阱（NETs）的形成和释放。这导致淋巴细胞浸润被排除在外，从而增强了治疗耐药性。更重要的是，我们设计了一种 DLL4 靶向的 CAR-T 来消除 DLL4 肿瘤细胞并逆转耐药状态。
本研究揭示了 DLL4 在细胞干性和免疫浸润中的新功能，包括 NET 形成和 T 细胞排斥，这些功能共同导致了 HER2 BC 中 THP 新辅助治疗耐药。此外，我们提供了一种基于 CAR-T 的治疗方法，以增敏 THP 新辅助治疗。
