Table1_Molecular subtyping of acute myeloid leukemia through ferroptosis signatures predicts prognosis and deciphers the immune microenvironment.XLS

Acute myeloid leukemia (AML) is one of the most aggressive hematological malignancies with a low 5-year survival rate and high rate of relapse. Developing more efficient therapies is an urgent need for AML treatment. Accumulating evidence showed that ferroptosis, an iron-dependent form of programmed cell death, is closely correlated with cancer initiation and clinical outcome through reshaping the tumor microenvironment. However, understanding of AML heterogeneity based on extensive profiling of ferroptosis signatures remains to be investigated yet. Herein, five independent AML transcriptomic datasets (TCGA-AML, GSE37642, GSE12417, GSE10358, and GSE106291) were obtained from the GEO and TCGA databases. Then, we identified two ferroptosis-related molecular subtypes (C1 and C2) with distinct prognosis and tumor immune microenvironment (TIME) by consensus clustering. Patients in the C1 subtype were associated with favorable clinical outcomes and increased cytotoxic immune cell infiltration, including CD8+/central memory T cells, natural killer (NK) cells, and non-regulatory CD4+ T cells while showing decreased suppressive immune subsets such as M2 macrophages, neutrophils, and monocytes. Functional enrichment analysis of differentially expressed genes (DEGs) implied that cell activation involved in immune response, leukocyte cell–cell adhesion and migration, and cytokine production were the main biological processes. Phagosome, antigen processing and presentation, cytokine–cytokine receptor interaction, B-cell receptor, and chemokine were identified as the major pathways. To seize the distinct landscape in C1 vs. C2 subtypes, a 5-gene prognostic signature (LSP1, IL1R2, MPO, CRIP1, and SLC24A3) was developed using LASSO Cox stepwise regression analysis and further validated in independent AML cohorts. Patients were divided into high- and low-risk groups, and decreased survival rates were observed in high- vs. low-risk groups. The TIME between high- and low-risk groups has a similar scenery in C1 vs. C2 subtypes. Single-cell-level analysis verified that LSP1 and CRIP1 were upregulated in AML and exhausted CD8+ T cells. Dual targeting of these two markers might present a promising immunotherapeutic for AML. In addition, potential effective chemical drugs for AML were predicted. Thus, we concluded that molecular subtyping using ferroptosis signatures could characterize the TIME and provide implications for monitoring clinical outcomes and predicting novel therapies.

急性髓系白血病（AML）作为一种侵袭性极强的血液系统恶性肿瘤，其五年生存率较低，复发率较高。针对AML的治疗，开发更为有效的疗法已成为当务之急。越来越多的证据表明，铁死亡，一种依赖铁的程序性细胞死亡形式，通过与重塑肿瘤微环境相互作用，与癌症的发生及临床转归密切相关。然而，基于对铁死亡特征进行广泛分析以了解AML异质性的研究尚待深入。本研究中，我们从GEO和TCGA数据库中获取了五个独立的AML转录组数据集（TCGA-AML、GSE37642、GSE12417、GSE10358和GSE106291）。随后，我们通过共识聚类识别出两种与铁死亡相关的分子亚型（C1和C2），这两种亚型具有不同的预后和肿瘤免疫微环境（TIME）。C1亚型的患者与良好的临床预后和增多的细胞毒性免疫细胞浸润相关，包括CD8+/中央记忆T细胞、自然杀伤（NK）细胞和非调节性CD4+ T细胞，同时显示出抑制性免疫亚群，如M2巨噬细胞、中性粒细胞和单核细胞的减少。差异表达基因（DEGs）的功能富集分析表明，涉及免疫反应、白细胞细胞间粘附和迁移以及细胞因子产生的细胞活化是主要的生物学过程。吞噬体、抗原处理和提呈、细胞因子-细胞因子受体相互作用、B细胞受体和趋化因子被确定为主要通路。为了捕捉C1与C2亚型之间的独特景观，我们利用LASSO Cox逐步回归分析开发了一个包含5个基因的预后特征（LSP1、IL1R2、MPO、CRIP1和SLC24A3），并在独立的AML队列中进行进一步验证。患者被分为高风险组和低风险组，高风险组与低风险组相比，生存率显著降低。高风险组和低风险组在C1与C2亚型中的TIME具有相似的景象。单细胞水平分析证实，LSP1和CRIP1在AML和耗竭的CD8+ T细胞中上调。针对这两个标记物的双重靶向治疗可能为AML提供一种有前景的免疫治疗方法。此外，还预测了潜在的AML有效化学药物。因此，我们得出结论，利用铁死亡特征进行分子分型可以表征TIME，并为监测临床结果和预测新型疗法提供启示。