De novo design of a two-step approach targeting Claudin-6 for enhanced drug delivery to solid tumors

作者：Jiayao Yan, Liqing Zhong, Xiaotong Chen, Lin Li, Fangcen Liu, Lei Lei, Mahru C. An, Wei Xiao, Ying Wang, Tianran Chen, Jingyi Guo, Jie Shao, Xiaoxiao Yu, Yingjie Zhao, Rutian Li, Qin Liu, Baorui Liu · 发表于：Journal of Translational Medicine · 年份：2025 · DOI：10.1186/s12967-025-07316-2 · 被引用次数：1 · 研究领域：Barrier Structure and Function Studies、Nanoparticle-Based Drug Delivery、Cancer Research and Treatments

BACKGROUND: Although antibody-conjugated drugs have achieved success in clinical practice for cancer treatment, challenges remain in developing a highly efficient drug delivery system with specific accumulation in tumors and reduction in side effects. With improved pharmacokinetics, strong covalent bonding and quick binding reactions, a pre-targeting approach via molecular pairs represents an attractive platform for two-step delivery system construction. METHODS: Bioinformatics and immunohistochemistry assays were performed to assess Claudin-6 (CLDN6) as a highly specific tumor target in solid tumors. A phage-displayed library was used to screen and optimize anti-CLDN6 designed ankyrin repeat proteins (DARPins), which were incorporated into a two-step delivery system based on SpyTag/SpyCatcher. Fluorescent staining, flow cytometry and near-infrared imaging were performed to assess the tumor-targeting ability and biodistribution of this delivery system. The cytotoxic drug, Monomethyl auristatin E (MMAE), was conjugated with the delivery system to evaluate its anti-tumor efficacy and safety profile. RESULTS: cancer cells with high affinity instead of negative cells in vitro, ex vivo and in vivo. The DARPins-based two-step delivery system improved background clearance with a high signal-to-noise ratio, enhancing the specific accumulation of payloads in tumors. The cytotoxic drug delivered via the two-step system appeared superior to the one-step approach in IC50, biodistribution...