Wang Shuhao, Zhu Lu, Wang Yubing, Han Yue, Wang Qingkun, Yang Wenqing, Zhao Lei, Zhang Yu, Pei Delong, Huang Wankun, Jin Aihua, Lin Zhenhua, Piao Junjie
Key Laboratory of Pathobiology (Yanbian University), State Ethnic Affairs Commission, Yanji, China.
Department of Urology, Linyi People's Hosiplital, Linyi, China.
Cell Death Dis. 2025 Jul 23;16(1):549. doi: 10.1038/s41419-025-07872-x.
Ferroptosis, a type of programmed cell death dependent on iron, is characterized by lipid peroxidation of cellular membranes. However, the roles and underlying mechanisms of RNA-binding proteins (RBPs) in modulating ferroptosis in colorectal cancer (CRC) have not been fully explored. In this study, RNA sequencing (RNA-seq) analysis identified ILF3, an RBP, as a crucial regulator of ferroptosis in CRC cells. Our research demonstrated that ILF3 depletion suppressed CRC cell growth and increased sensitivity to ferroptosis. Combined analysis of RNA-seq data and amino acid metabolomics indicated a relationship between ILF3 and glutathione (GSH) synthesis. Further investigation confirmed that ILF3 knockdown reduced GSH synthesis by regulating SLC3A2-mediated cystine uptake. Mechanistically, ILF3 enhances SLC3A2 mRNA stability by interacting with its 3' UTR, leading to increased cystine uptake. Notably, our observations revealed a frequent increase in ILF3 levels in patients with CRC, which was associated with poor prognosis. The elevated ILF3 expression in CRC appears to be partly due to stimulation by tumor necrosis factor alpha (TNF-α) from the tumor inflammatory microenvironment. Additionally, TNF-α was found to decrease sensitivity to ferroptosis by promoting ILF3 expression. Co-immunoprecipitation and liquid chromatography-mass spectrometry assays revealed that the E3 ligase TRIM17 is involved in TNF-α-induced ILF3 upregulation. Specifically, TNF-α inhibited the interaction between ILF3 and TRIM17, thereby protecting ILF3 from ubiquitin-mediated degradation. This resulted in increased ILF3 levels that counteracted ferroptosis. In summary, our study underscores the oncogenic function of ILF3 in CRC and suggests that ILF3 knockdown may serve as a promising therapeutic approach for CRC.
铁死亡是一种依赖铁的程序性细胞死亡，其特征是细胞膜发生脂质过氧化。然而，RNA结合蛋白（RBPs）在调节结直肠癌（CRC）铁死亡中的作用及潜在机制尚未得到充分研究。在本研究中，RNA测序（RNA-seq）分析确定了一种RBP——白细胞介素增强子结合因子3（ILF3），它是CRC细胞中铁死亡的关键调节因子。我们的研究表明，ILF3的缺失抑制了CRC细胞的生长，并增加了对铁死亡的敏感性。RNA-seq数据与氨基酸代谢组学的联合分析表明ILF3与谷胱甘肽（GSH）合成之间存在关联。进一步研究证实，ILF3的敲低通过调节溶质载体家族3成员2（SLC3A2）介导的胱氨酸摄取来减少GSH合成。机制上，ILF3通过与其3'非翻译区（UTR）相互作用增强SLC3A2 mRNA的稳定性，从而导致胱氨酸摄取增加。值得注意的是，我们的观察结果显示CRC患者中ILF3水平经常升高，这与预后不良相关。CRC中ILF3表达的升高似乎部分归因于肿瘤炎性微环境中肿瘤坏死因子α（TNF-α）的刺激。此外，发现TNF-α通过促进ILF3表达来降低对铁死亡的敏感性。免疫共沉淀和液相色谱-质谱分析表明，E3泛素连接酶TRIM17参与了TNF-α诱导的ILF3上调。具体而言，TNF-α抑制了ILF3与TRIM17之间的相互作用，从而保护ILF3免受泛素介导的降解。这导致ILF3水平升高，抵消了铁死亡。总之，我们的研究强调了ILF3在CRC中的致癌功能，并表明敲低ILF3可能是一种有前景的CRC治疗方法。
