MKRN1降解AGC1以引发结直肠癌的化疗耐药性。

MKRN1 degrades AGC1 to trigger chemotherapy resistance of colorectal Cancer.

作者信息

Wang Yixuan, Qiao Mu, Guo Jing, Xie Ying, Hu Meilin, Li Xin, Wang Sheng, Wang Jingjing, Wang Jingya, Peng Ziyi, Wang Mengqi, Cheng Hao, Li Tiantian, Jia Linchuang, Su Danchen, Liu Huanhuan, Hu Kexin, Li Xinyang, Li Wenjing, Wu Di, Zhang Zhe, Han Jianing, Bai Ruiyang, Zhou Funan, Liu Zhiqiang

机构信息

The province and ministry co-sponsored collaborative innovation center for medical epigenetics, Department of Physiology and Pathophysiology, School of Basic Medical Science, Tianjin Medical University, Heping, Tianjin, 300070, China.

Shandong Provincial Key Laboratory of Precision Oncology, Shandong Cancer Hospital and Institute, Shandong First Medical University, Shandong Academy of Medical Sciences, Jinan, 250117, Shandong, China.

出版信息

Mol Med. 2025 Jul 28;31(1):268. doi: 10.1186/s10020-025-01287-2.

DOI:10.1186/s10020-025-01287-2

PMID:40722058

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC12302804/

Abstract

UNLABELLED

Oxaliplatin (Oxa) has been extensively employed in treatment of colorectal cancer (CRC), yet frequent occurrence of chemoresistance poses a significant obstacle to achieving long-term disease-free survival for CRC patients. In this study, we employed a CRISPR/Cas9 sgRNA library targeting 1,117 human ubiquitination-related genes to screen key regulators of sensitivity to Oxa and identified the Makorin Ring Finger Protein 1 (MKRN1), an E3 ligase, as an Oxa-resistant gene of CRC cells. Clinically, MKRN1 is highly expressed in CRC tissues compared with the adjacent normal tissue, and its upregulation is correlated with poor therapeutic response, disease progression, and worse overall survival of CRC patients treated with Oxa-based regimens. In CRC cells, gain- and loss-of-function studies of MKRN1 respectively altered the sensitivity to Oxa treatment, as evidenced by changes in IC50 values and cell apoptosis. Mechanistic analysis revealed that MKRN1 interacts with Aspartate/Glutamate Carrier 1 (AGC1), facilitating degradation of AGC1 via K11- and K29-linked ubiquitination, thereby affecting mitochondrial function including energy metabolism and antioxidant responses. Through reprogramming of metabolic genes, this process enhances the expression of heat shock protein HSPD1 and HSP90AA1, while reducing oxidative stress, ultimately contributing to the development of Oxa resistance in CRC cells. Moreover, AGC1 knockdown rescued the MKRN1-deficiency induced Oxa-sensitivity of CRC cells and in xenograft mouse model. Translationally, we identified Rabdosiin as a potential inhibitor of MKRN1 through virtual screening, and validated the synergetic effect of Rabdosiin and Oxa in treating Oxa-resistant CRC cells both in vitro and in vivo. Taken together, our findings highlight the pivotal role of MKRN1-AGC1 axis in dictating CRC chemoresistance and offer novel therapeutic strategies for overcoming Oxa-resistance.

GRAPHICAL ABSTRACT

[Image: see text]

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1186/s10020-025-01287-2.

摘要

未标记

奥沙利铂（Oxa）已广泛应用于结直肠癌（CRC）的治疗，但化疗耐药的频繁发生对CRC患者实现长期无病生存构成了重大障碍。在本研究中，我们使用了一个靶向1117个人类泛素化相关基因的CRISPR/Cas9 sgRNA文库来筛选对奥沙利铂敏感性的关键调节因子，并确定了E3连接酶Makorin环指蛋白1（MKRN1）是CRC细胞的奥沙利铂耐药基因。临床上，与相邻正常组织相比，MKRN1在CRC组织中高表达，其上调与接受基于奥沙利铂方案治疗的CRC患者的治疗反应差、疾病进展和总体生存率低相关。在CRC细胞中，MKRN1的功能获得和缺失研究分别改变了对奥沙利铂治疗的敏感性，IC50值和细胞凋亡的变化证明了这一点。机制分析表明，MKRN1与天冬氨酸/谷氨酸载体1（AGC1）相互作用，通过K11和K29连接的泛素化促进AGC1的降解，从而影响包括能量代谢和抗氧化反应在内的线粒体功能。通过代谢基因的重编程，这一过程增强了热休克蛋白HSPD1和HSP90AA1的表达，同时降低了氧化应激，最终导致CRC细胞对奥沙利铂耐药的发展。此外，AGC1敲低挽救了MKRN1缺陷诱导的CRC细胞对奥沙利铂的敏感性，并在异种移植小鼠模型中得到验证。在转化研究中，我们通过虚拟筛选确定了夏枯草苷是MKRN1的潜在抑制剂，并在体外和体内验证了夏枯草苷和奥沙利铂在治疗奥沙利铂耐药CRC细胞中的协同作用。综上所述，我们的研究结果突出了MKRN1-AGC1轴在决定CRC化疗耐药中的关键作用，并为克服奥沙利铂耐药提供了新的治疗策略。