Interleukin-33 (IL-33) is an epithelial-derived cytokine that can be released upon tissue damage, stress, or infection, acting as an alarmin for the immune system. IL-33 has long been studied in the context of Th2-related immunopathologies, such as allergic diseases and parasitic infections. However, its capacity to stimulate also Th1-type of immune responses is now well established. IL-33 binds to its specific receptor ST2 expressed by most immune cell populations, modulating a variety of responses. In cancer immunity, IL-33 can display both pro-tumoral and anti-tumoral functions, depending on the specific microenvironment. Recent findings indicate that IL-33 can effectively stimulate immune effector cells (NK and CD8⁺ T cells), eosinophils, basophils and type 2 innate lymphoid cells (ILC2) promoting direct and indirect anti-tumoral activities. In this review, we summarize the most recent advances on anti-tumor immune mechanisms operated by IL-33, including the modulation of immune checkpoint molecules, with the aim to understand its potential as a therapeutic target in cancer.

白细胞介素33（IL-33）是一种上皮细胞因子，可在组织损伤，压力或感染后释放，充当免疫系统的警报蛋白。长期以来，人们一直在与Th2相关的免疫病理学（例如过敏性疾病和寄生虫感染）中研究IL-33。但是，现在已经充分确立了其刺激Th1型免疫应答的能力。IL-33与大多数免疫细胞群表达的特定受体ST2结合，从而调节多种反应。在癌症免疫力方面，IL-33可以显示促肿瘤和抗肿瘤功能，具体取决于特定的微环境。最新发现表明，IL-33可以有效刺激免疫效应细胞（NK和CD8 ⁺T细胞），嗜酸性粒细胞，嗜碱性粒细胞和2型先天性淋巴样细胞（ILC2）促进直接和间接的抗肿瘤活性。在这篇综述中，我们总结了由IL-33操纵的抗肿瘤免疫机制的最新进展，包括调节免疫检查点分子，目的是了解其作为癌症治疗靶标的潜力。