前列腺癌（PCa）仍然是男性癌症相关死亡率的一个重要问题。肿瘤的发展受到肿瘤细胞与其微环境之间复杂相互作用的复杂调节，因此有必要确定哪些是影响肿瘤微环境中PCa进展的关键因素。当前的研究利用组织病理学和免疫组织化学来确定检测PCa中IL-38的表达情况，并分析PCa内IL-38表达水平与临床病理特征的相关性。与癌旁非PCa组织相比，PCa组织中IL-38的表达量显着升高（P < 0.0001）。此外，与低增值指数的肿瘤细胞相比，高增殖指数的肿瘤细胞中IL-38的表达显着较高。 ROC曲线分析表明IL-38对PCa的诊断具有较高的特异性和敏感性（AUC=0.76）。此外，我们通过免疫荧光双染法探讨了前列腺癌组织中IL-38的细胞来源。此外，在 PCa 中，IL-38 的表达与 CD8 和 PD-1 的表达水平呈负相关。生存分析显示，IL-38高表达的PCa患者总生存率显着较低（P=0.0069），且当IL-38与CD8共表达时，IL-38high/CD8low组的生存率显着下降。多变量分析表明IL-38的表达水平和TNM分期是PCa患者生存的独立预测因子。这些结果提示IL-38在PCa的发生发展中发挥着至关重要的作用，探索IL-38与PCa的相关性肿瘤微环境中的各种免疫因子进一步揭示了其作用机制，使其成为PCa免疫治疗的潜在靶点。版权所有©2024 Wu，Yang，Yuan，Tan，Zhang，Hambly，Bao和Tao。

Prostate Cancer (PCa) remains a significant concern in male cancer-related mortality. Tumour development is intricately regulated by the complex interactions between tumour cells and their microenvironment, making it essential to determine which is/are key factor(s) that influence the progression of PCa within the tumour microenvironment.The current study utilised histopathology and immunohistochemistry to determine the expression of IL-38 in PCa and analysed the correlation between the expression level of IL-38 within PCa and clinical pathological characteristics.There was a significant increase in IL-38 expression in PCa tissues compared to adjacent non-PCa tissues (P < 0.0001). In addition, IL-38 expression was significantly higher in tumour cells with a high proliferation index compared to those with a low value-added index. ROC curve analysis demonstrated that IL-38 has high specificity and sensitivity for the diagnosis of PCa (AUC=0.76). Moreover, we Probed the cellular source of IL-38 in prostate cancer tissue by immunofluorescence double staining. Additionally, within PCa, the expression of IL-38 was inversely correlated with the expression levels of CD8 and PD-1. Survival analysis revealed a significantly lower overall survival rate for PCa patients with high IL-38 expression (P=0.0069), and when IL-38 was co-expressed with CD8, the survival rate of the IL-38high/CD8low group was decreased significantly. Multivariate analysis indicated that the expression level of IL-38 and TNM staging were independent predictors of survival in PCa patients.These findings suggest that IL-38 plays a crucial role in the development of PCa, and the exploration of the correlation between IL-38 and various immune factors in the tumour microenvironment further reveals its mechanism of action, making it a potential target for immunotherapy in PCa.Copyright © 2024 Wu, Yang, Yuan, Tan, Zhang, Hambly, Bao and Tao.