Microwave thermochemotherapy (MTC) has been applied to treat lip squamous cell carcinoma (LSCC), but a deeper understanding of its therapeutic mechanisms and molecular biology is needed. To address this, we used single-cell transcriptomics (scRNA-seq) and spatial transcriptomics (ST) to highlight the pivotal role of tumor-associated neutrophils (TANs) among tumor-infiltrating immune cells and their therapeutic response to MTC. MNDA⁺ TANs with anti-tumor activity (N1-phenotype) are found to be abundantly infiltrated by MTC with benefit of increased blood perfusion, and these TANs are characterized by enhanced cytotoxicity, ameliorated hypoxia, and upregulated IL1B, activating T&NK cells and fibroblasts via IL1B-IL1R. In this highly anti-tumor immunogenic and hypoxia-reversed microenvironment under MTC, fibroblasts accumulated in the tumor front (TF) can recruit N1-TANs via CXCL2-CXCR2 and clear N2-TANs (pro-tumor phenotype) via CXCL12-CXCR4, which results in the aggregation of N1-TANs and extracellular matrix (ECM) deposition. In addition, we construct an N1-TANs marker, MX2, which positively correlates with better prognosis in LSCC patients, and employ deep learning techniques to predict expression of MX2 from hematoxylin-eosin (H&E)-stained images so as to conveniently guide decision making in clinical practice. Collectively, our findings demonstrate that the N1-TANs/fibroblasts defense wall formed in response to MTC effectively combat LSCC.

© 2025. The Author(s).

微波热化疗（MTC）已被用于治疗唇部鳞状细胞癌（LSCC），但对其治疗机制和分子生物学的理解仍需进一步深入。为了解决这个问题，我们使用了单细胞转录组学（scRNA-seq）和空间转录组学（ST）来突出肿瘤浸润免疫细胞中肿瘤相关中性粒细胞（TANs）的关键作用及其对MTC的治疗反应。研究发现，在MTC的作用下，具有抗肿瘤活性（N1表型）的MNDA⁺ TANs大量渗入，并且这些TANs通过增强的细胞毒性、改善的缺氧状态以及上调IL1B而被激活，进而通过IL1B-IL1R途径激活T和NK细胞及成纤维细胞。在MTC作用下形成的这种高度抗肿瘤免疫性和逆转缺氧的小环境中，聚集于肿瘤前沿（TF）的成纤维细胞可通过CXCL2-CXCR2招募N1-TANs，并通过CXCL12-CXCR4清除具有促肿瘤表型的N2-TANs，从而导致N1-TANs和细胞外基质（ECM）沉积的聚集。此外，我们构建了一个与LSCC患者预后更好的MX2标记物，利用深度学习技术从苏木精-伊红染色图像预测MX2表达水平，以便在临床实践中方便地指导决策制定。综上所述，我们的研究结果表明，响应于MTC形成的N1-TANs/成纤维细胞防御墙有效地对抗LSCC。

© 2025. 作者保留所有权利。