Wang Qiang, Ren Shiheng, Pan Zheng, Chen Yuxin, Liu Xiangyan
Department of Thoracic Surgery, Shandong Provincial Hospital, Cheeloo College of Medicine, Shandong University, Jinan, Shandong, China.
Department of Thoracic Surgery, The People's Hospital of Laoling City, Dezhou, China.
Thorac Cancer. 2025 Feb;16(4):e70013. doi: 10.1111/1759-7714.70013.
Chemo-resistance is a major obstacle to the treatment of esophageal squamous cell carcinoma (ESCC). Interferon alpha-inducible protein 27 (IFI27) has been reported to be associated with ESCC progression. This study is designed to explore the role and mechanism of IFI27 in the cisplatin (DDP) resistance of ESCC.
IFI27 and Ubiquitin-specific peptidase 18 (USP18) levels were detected by real-time quantitative polymerase chain reaction (RT-qPCR). IFI27, multidrug resistance-associated protein 1 (MRP1), USP18, and Homeobox A5 (HOXA5) protein levels were determined using western blot. DDP resistance, cell viability, proliferation, apoptosis, invasion, and migration were assessed using MTT, EdU, flow cytometry, transwell, and wound healing. Interaction between USP18 and IFI27 was verified using Co-immunoprecipitation (CoIP) assay. Binding between HOXA5 and USP18 promoter was predicted by JASPAR and validated using Chromatin immunoprecipitation (ChIP) and dual-luciferase reporter assays.
IFI27 was upregulated in DDP-resistant ESCC tissues and cells. IFI27 knockdown repressed DDP resistance, cell proliferation, invasion, migration, and induced cell apoptosis in vitro. Mechanistically, USP18 induced the deubiquitination of IFI27 and prevented its degradation. Furthermore, HOXA5 was a transcription factor of USP18 and activated the transcriptional activity of USP18 via binding to its promoter region.
USP18 transcriptionally mediated by HOXA5 could promote cell malignant behaviors and DDP resistance through deubiquitinating IFI27, providing a promising therapeutic target for ESCC treatment.
化疗耐药是食管鳞状细胞癌（ESCC）治疗的主要障碍。据报道，干扰素α诱导蛋白27（IFI27）与ESCC进展相关。本研究旨在探讨IFI27在ESCC顺铂（DDP）耐药中的作用及机制。
采用实时定量聚合酶链反应（RT-qPCR）检测IFI27和泛素特异性蛋白酶18（USP18）水平。使用蛋白质免疫印迹法测定IFI27、多药耐药相关蛋白1（MRP1）、USP18和同源框A5（HOXA5）蛋白水平。采用MTT法、EdU法、流式细胞术、Transwell法和伤口愈合实验评估DDP耐药性、细胞活力、增殖、凋亡、侵袭和迁移。使用免疫共沉淀（CoIP）实验验证USP18与IFI27之间的相互作用。通过JASPAR预测HOXA5与USP18启动子之间的结合，并使用染色质免疫沉淀（ChIP）和双荧光素酶报告基因实验进行验证。
IFI27在DDP耐药的ESCC组织和细胞中上调。IFI27基因敲低可抑制体外DDP耐药性、细胞增殖、侵袭、迁移并诱导细胞凋亡。机制上，USP18诱导IFI27去泛素化并防止其降解。此外，HOXA5是USP18的转录因子，通过与其启动子区域结合激活USP18的转录活性。
HOXA5转录介导的USP18可通过使IFI27去泛素化促进细胞恶性行为和DDP耐药，为ESCC治疗提供了一个有前景的治疗靶点。
