Transformable Peptide Nanocarriers for Expeditious Drug Release and Effective Cancer Therapy via Cancer‐Associated Fibroblast Activation

A novel cleavable amphiphilic peptide (CAP) was designed to be specifically responsive to fibroblast activation protein-α (FAP-α), a protease specifically expressed on the surface of cancer-associated fibroblasts. The CAP self-assembled into fiber-like nanostructures in solution, while the presence of hydrophobic chemotherapeutic drugs readily transformed the assemblies into drug-loaded spherical nanoparticles. The disassembly of these nanoparticles (CAP-NPs) upon FAP-α cleavage resulted in rapid and efficient release of the encapsulated drugs specifically at tumor sites. This Transformers-like drug delivery strategy could allow them to disrupt the stromal barrier and enhance local drug accumulation. Therapeutic results suggested that drug-loaded CAP-NPs hold promising tumor specificity and therapeutic efficacy for various solid tumor models, confirming its potential utility and versatility in antitumor therapy.