Smart dual-ligand-functionalized magnetic nanocomposites for rapid disruption of EpCAM-positive extracellular vesicles.

BACKGROUND

Epithelial Cell Adhesion Molecule positive (EpCAM+) extracellular vesicles (EVs) can promote cancer progression and metastasis. Thus, it is necessary to develop targeted strategies to disable EpCAM+ EVs.

RESULTS

In this work, inspired by the ability of antiviral curvature-sensing peptides to disrupt highly curved lipid membranes (<300 nm diameter), we develop magnetic nanoparticles co-functionalized with curvature-sensing peptide AH-D and EpCAM aptamer (denoted AH-D/Apt@MNP) for synergistic targeting and disruption of EpCAM+ EVs. Transmission electron microscopy (TEM) visually revealed a rapid three-stage disruption process of EpCAM+ EVs triggered by AH-D/Apt@MNP: EVs became discoid at 2 min, underwent membrane rupture and asymmetric budding at 5 min, and fully disintegrated into 20-50 nm protein-lipid debris at 10 min, whereas EpCAM- EVs with low EpCAM expression remained structurally intact with negligible alterations. Moreover, protease digestion assays verified that AH-D/Apt@MNP treatment led to the release of luminal protein TSG101 from EpCAM+ EVs. In proof-of-concept experiments, AH-D/Apt@MNP was applied to disrupt the EpCAM+ subpopulation of plasma-derived EVs from breast cancer patients. Scratch and Transwell assays demonstrated that AH-D/Apt@MNP with good biocompatibility significantly suppressed breast cancer cell migration compared with plasma EVs alone. Furthermore, AH-D/Apt@MNP normalized the secretion of inflammatory cytokines and suppressed the upregulation of Programmed Death-Ligand 1 (PD-L1) in macrophages induced by EpCAM+ EVs.

SIGNIFICANCE: These results demonstrate the feasibility of using the nanocomposites for disruption of EpCAM + EVs in complex samples through a rapid and efficient process. Our strategy may offer promising guidance to develop new magnetic biocomposites functionalized with various ligands, enabling future targeting of EVs derived from different tumors.