2. Academic Validation
  3. De novo design of a two-step approach targeting Claudin-6 for enhanced drug delivery to solid tumors

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

  • J Transl Med. 2025 Nov 20;23(1):1323. doi: 10.1186/s12967-025-07316-2.
Jiayao Yan # 1,  Liqing Zhong # 1,  Xiaotong Chen 1,  Lin Li 2,  Fangcen Liu 2,  Lei Lei 3,  Mengchao An 4,  Xiao Wei 2,  Ying Wang 1,  Tianran Chen 1,  Jingyi Guo 5,  Jie Shao 1,  Xiaoxiao Yu 6,  Yingjie Zhao 7,  Rutian Li 8,  Qin Liu 9 10,  Baorui Liu 11 12 13 14
Affiliations

Affiliations

  • 1 Department of Oncology, Nanjing Drum Tower Hospital, Affiliated Hospital of Medical School, Nanjing University, Nanjing, China.
  • 2 Department of Pathology, Nanjing Drum Tower Hospital, Affiliated Hospital of Medical School, Nanjing University, Nanjing, China.
  • 3 Zhongda Hospital, School of Medicine, Southeast University, Nanjing, China.
  • 4 The Comprehensive Cancer Center, Nanjing Drum Tower Hospital, Clinical College of Nanjing Medical University, Nanjing, China.
  • 5 Department of Oncology, Nanjing Drum Tower Hospital, China Pharmaceutical University, Nanjing, China.
  • 6 School of Life Sciences, Nanjing University, Nanjing, China.
  • 7 Department of Biology, Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, USA.
  • 8 Department of Oncology, Nanjing Drum Tower Hospital, Affiliated Hospital of Medical School, Nanjing University, Nanjing, China. [email protected].
  • 9 Department of Oncology, Nanjing Drum Tower Hospital, Affiliated Hospital of Medical School, Nanjing University, Nanjing, China. [email protected].
  • 10 Department of Oncology, Nanjing Drum Tower Hospital & Group's Suqian Hospital, Affiliated Hospital of Medical School, Nanjing University, Nanjing, China. [email protected].
  • 11 Department of Oncology, Nanjing Drum Tower Hospital, Affiliated Hospital of Medical School, Nanjing University, Nanjing, China. [email protected].
  • 12 The Comprehensive Cancer Center, Nanjing Drum Tower Hospital, Clinical College of Nanjing Medical University, Nanjing, China. [email protected].
  • 13 Department of Oncology, Nanjing Drum Tower Hospital, China Pharmaceutical University, Nanjing, China. [email protected].
  • 14 Department of Oncology, Nanjing Drum Tower Hospital & Group's Suqian Hospital, Affiliated Hospital of Medical School, Nanjing University, Nanjing, China. [email protected].
  • # Contributed equally.
PMID: 41267074 DOI: 10.1186/s12967-025-07316-2
Abstract

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: Anti-CLDN6 DARPins exhibited specific binding to CLDN6+ 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, and tumor growth inhibition.

Conclusions: Our study presented the de novo design of a two-step drug delivery system targeting Claudin-6 with enhanced anti-tumor efficacy and improved biosafety. These findings highlighted the potential of this approach to enhance the efficacy of tumor-targeting therapies and reduce adverse effects, paving the way for more effective Cancer treatments.

Keywords

CLDN6; DARPins; Phage display; Pre-targeting.

Figures
Products