Abstract
Radiotherapy is a critical modality in cancer treatment, not only to eradicate cancer cells but also to trigger anti-tumor immunity. Interleukin-21 (IL-21), an immunomodulatory cytokine with potential in cancer therapy, has unexplored synergy with radiotherapy. Our study, leveraging human cancer databases and tissue microarrays, identified a positive correlation between IL-21 and radiotherapy outcomes, particularly in tumor microenvironment (TME) activation. In mouse tumor models, IL-21 combined with radiation significantly enhances TME, boosting CD8+ T cell activation and function, reducing tumor burden, and extending survival. Single-cell transcriptome sequencing revealed that the combination of IL-21 and radiation increased the cytotoxicity of effector and memory CD8+ T cells and prevented their exhaustion. These effects were further validated in humanized mice, where IL-21 combined with radiation reduced A549 tumor growth and enhanced CD8+ T cell function. Post-neoadjuvant radiotherapy samples from patients with esophageal cancer showed a positive correlation between IL-21 levels and CD8+ T cell infiltration. Our findings suggest that IL-21 is a promising adjuvant to radiotherapy, potentially improving the treatment efficacy through TME enhancement. This study provides a foundation for future clinical exploration of IL-21 for enhancing radiotherapy.
Authors
Xinyang Li, Xueqi Xie, Baochao Wei, Xiaozheng Sun, Minxin Chen, Rufei Liu, Qingxu Tao, Yiheng Huang, Qian Wang, Shuangshuang Ma, Ling Wei, Rong Xiao, Zhaoyun Liu, Jinming Yu, Meng Wu, Dawei Chen
