[摘 要] 目的：探究吲哚胺2，3-双加氧酶1（IDO1）在不同类型乳腺癌组织中的表达及其与患者预后和免疫细胞浸润的关系。 方法：收集 TCGA 数据库中乳腺癌RNA测序数据和相应临床资料，分析IDO1 mRNA在不同亚型、不同分期、不同绝经阶段及不 同年龄等各类型乳腺癌组织与癌旁组织中的表达差异。将IDO1 mRNA表达有明显差异的乳腺癌类型的患者分为IDO1高、低表 达组，比较3组间的疾病特异性生存率（DSS），分析IDO1 mRNA在DSS有明显差异的癌组织中的表达水平与免疫细胞浸润的关 系。采用免疫组化法检测IDO1蛋白在ER阴性、PR阴性、HER2阳性及Ⅱ期乳腺癌组织中的表达情况，对数据库数据进行验证。 结果：IDO1 mRNA在乳腺癌组织中呈高表达，但在不同类型乳腺癌中的表达不同。IDO1 mRNA在ER阴性、PR阴性、HER2阳 性、HER2阴性亚型、Ⅱ期、T2期、N0期和M0期分期、绝经前、绝经后和年龄≤ 60岁患者的乳腺癌组织中呈高表达（P < 0.05或P < 0.01或P < 0.001）。ER阴性、PR阴性、HER2阳性和Ⅱ期亚组中，IDO1 mRNA高表达患者的DSS明显高于低表达患者（P < 0.05 或P < 0.01）。ER阴性、PR阴性、HER2阳性和Ⅱ期乳腺癌组织中IDO1 mRNA表达与活化的树突状细胞（aDC）、Th1细胞、T细 胞、CD56dim NK细胞、CTL和Treg细胞等免疫细胞浸润有关联（均P < 0.001）。IDO1蛋白在ER阴性、PR阴性、HER2阳性及Ⅱ期 乳腺癌组织中均呈高表达（均P < 0.001），与数据库数据分析结果一致。结论：IDO1在不同类型的乳腺癌组织中的表达不同， IDO1表达与ER阴性、PR阴性、HER2阳性和Ⅱ期乳腺癌患者的预后和免疫细胞浸润有关联。

[Abstract] Objective: To investigate the expression of indoleamine 2,3-dioxygenase 1 (IDO1) in different types of breast cancer tissues and its relationship with patient prognosis and immune cell infiltration. Methods: RNA sequencing data of breast cancer and corresponding clinical information from the TCGA database were collected. The differential expression of IDO1 mRNA in various breast cancer tissues (different subtypes, stages, menopause statuses, and age groups) and adjacent normal tissues were analyzed. Breast cancer patients with significant differences in IDO1 mRNA expression were divided into high and low expression groups, and their disease-specific survival (DSS) was compared between the two groups. The relationship between IDO1 mRNA expression and immune cell infiltration in cancer tissues with significant DSS differences was analyzed. Immunohistochemistry was used to detect IDO1 protein expression in ER-negative, PR-negative, HER2-positive, and stage Ⅱ breast cancer tissues, to verify the data from the database. Results: IDO1 mRNA was highly expressed in breast cancer tissues but varied across different breast cancer types. IDO1 mRNA was highly expressed in breast cancer tissues of patients with ER-negative, PR-negative, HER2-positive, HER2-negative subtypes, stage Ⅱ, T2 stage, N0 stage, M0 stage, premenopausal, postmenopausal, and age ≤ 60 years (P < 0.05 or P < 0.01, or P < 0.001). In the ER negative, PR-negative, HER2-positive, and stage Ⅱ subgroups, breast cancer tissues patients with high IDO1 mRNA expression had significantly higher DSS than those with low expression (P < 0.05 or P < 0.01). In ER-negative, PR-negative, HER2-positive, and stage Ⅱ breast cancer tissues, IDO1 mRNA expression was associated with immune cell infiltration, including activated dendritic cells (aDCs), Th1 cells, T cells, CD56dim NK cells, CTLs, and Treg cells (all P < 0.001). IDO1 protein was highly expressed in ER-negative, PR-negative, HER2-positive, and stage Ⅱ breast cancer tissues (all P < 0.001), consistent with the data from the database. Conclusion: IDO1 expression varies across different types of breast cancer tissues. The expression of IDO1 is associated with the prognosis and immune cell infiltration in ER-negative, PR-negative, HER2-positive, and at stage Ⅱ breast cancer patients.

贵州省卫生健康委科学技术基金（No. gzwkj2022-229）；贵州省省级科技计划（黔科合基础[2020]1Y344）