TAK1 Is a Novel Target in Hepatocellular Carcinoma and Contributes to Sorafenib Resistance

作者：Shunjie Xia, Lin Ji, Liye Tao, Yu Pan, Zhongjie Lin, Zhe Wan, Haoqi Pan, Jie Zhao, Liuxin Cai, Junjie Xu, Xiujun Cai · 发表于：Cellular and Molecular Gastroenterology and Hepatology · 年份：2021 · DOI：10.1016/j.jcmgh.2021.04.016 · 被引用次数：33 · 研究领域：Cancer Mechanisms and Therapy、NF-κB Signaling Pathways、Melanoma and MAPK Pathways

BACKGROUND & AIMS: Identifying novel and actionable targets in hepatocellular carcinoma (HCC) remains an unmet medical need. TAK1 was originally identified as a transforming growth factor-β-activated kinase and was further proved to phosphorylate and activate numerous downstream targets and promote cancer progression. However, the role of TAK1 in developed HCC progression and targeted therapy resistance is poorly understood. METHODS: The expression of TAK1 or MTDH in HCC cell lines, tumor tissues, and sorafenib-resistant models was analyzed by in silico analysis, quantitative real-time polymerase chain reaction, Western blotting, and immunohistochemistry. In vivo and in vitro experiments were introduced to examine the function of TAK1 or MTDH in HCC and sorafenib resistance using small interfering RNA and pharmacologic inhibitors in combination with or without sorafenib. Co-immunoprecipitation and RNA immunoprecipitation were carried out to determine the binding between TAK1 and FBXW2 or between MTDH and FBXW2 mRNA. Protein half-life and in vitro ubiquitination experiment was performed to validate whether FBXW2 regulates TAK1 degradation. RESULTS: Our findings unraveled the clinical significance of TAK1 in promoting HCC and sorafenib resistance. We identified a novel E3 ubiquitin ligase, FBXW2, targeting TAK1 for K48-linked polyubiquitylation and subsequent degradation. We also found that MTDH contributes to TAK1 up-regulation in HCC and sorafenib resistance through binding t...