Xing Zhichao, Cai Xiaoying, He Ting, Li Peiheng, He Jun, Qiu Yuxuan, Li Na, Mi Li, Li Ruixi, Zhu Jingqiang, Li Zhihui, Su Anping, Ye Haoyu, Wu Wenshuang
Division of Thyroid Surgery, Department of General Surgery and Laboratory of Thyroid and Parathyroid Disease, Frontiers Science Center for Disease-related Molecular Network, West China Hospital, Sichuan University, Chengdu 610041, China.
Department of Biotherapy, Cancer Center and State Key laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu 610041, China.
Proc Natl Acad Sci U S A. 2025 May 13;122(19):e2416045122. doi: 10.1073/pnas.2416045122. Epub 2025 May 8.
DNA damage repair (DDR) is essential for cancer cell survival and treatment resistance, making it a critical target for tumor therapy. The eukaryotic AAA+ adenosine triphosphatase valosin-containing protein (VCP), which is transported from the cytoplasm into the nucleus, plays a critical role in the DDR process. However, the nuclear translocation and molecular mechanism of VCP for DDR remain elusive. Here, we define VCP as a KPNB1 interacting protein through a combination of chemical and immunoprecipitation mass spectrometry approaches. Further biochemical studies elucidate that KPNB1 directly transports VCP into the nucleus. We also identify withaferin A (WA) as a small molecule that can retard VCP nuclear localization via covalent binding to CYS 158 of KPNB1. Further studies verify WA as an effective antitumor drug candidate via blocking VCP nuclear localization to impact on the DDR pathway in vivo. Our findings underly the unclear VCP's role in DDR in a KPNB1-dependent manner and provide an important theoretical basis for developing small-molecule inhibitors targeting this process.
DNA损伤修复（DDR）对于癌细胞存活和治疗抗性至关重要，使其成为肿瘤治疗的关键靶点。真核生物AAA+三磷酸腺苷酶含缬酪肽蛋白（VCP）从细胞质转运到细胞核中，在DDR过程中起关键作用。然而，VCP用于DDR的核转位和分子机制仍不清楚。在这里，我们通过化学和免疫沉淀质谱方法相结合将VCP定义为一种与核转运蛋白β1（KPNB1）相互作用的蛋白。进一步的生化研究阐明KPNB1直接将VCP转运到细胞核中。我们还鉴定出白屈菜赤碱（WA）作为一种小分子，它可以通过与KPNB1的半胱氨酸158共价结合来延缓VCP的核定位。进一步的研究通过在体内阻断VCP核定位以影响DDR途径，验证WA作为一种有效的抗肿瘤药物候选物。我们的研究结果以KPNB1依赖的方式揭示了VCP在DDR中尚不清楚的作用，并为开发针对这一过程的小分子抑制剂提供了重要的理论基础。
