Reduction-triggered polycyclodextrin supramolecular nanocage induces immunogenic cell death for improved chemotherapy.

Polycyclodextrin-based supramolecular nanoplatform crosslinked by stimuli-responsive moiety shows great promise in cancer therapy owing to its superior bio-stability and feasible modification of architectures. Here, the endogenous glutathione (GSH)-responsive polycyclodextrin supramolecular nanocages (PDOP NCs) are constructed by covalent crosslinking of multiple β-cyclodextrin (β-CD) molecules. The polycyclodextrin provide sites for conjugation of chemotherapeutic doxorubicin (DOX). Meanwhile, the PDOP NCs are stabilized by multiple interactions including host-guest interaction between DOX and β-CD and hydrogen bonds between β-CD units. The supramolecular crosslinked structure endowed the nanocage with high stability and drug loading capacity. Tons of GSH-sensitive disulfide linkages in PDOP NCs were broken at tumor cells, promoting tumor-specific DOX release. Besides, the redox equilibrium in tumor microenvironment could be disturbed due to GSH depletion, which further sensitized the DOX effects and alleviated drug resistance, facilitating inducing immunogenic cell death effect for enhanced chemotherapy, thereby achieving efficient tumor suppression and prolonged survival. Thus, the versatile polycyclodextrin-based supramolecular nanocage provides a novel and efficient drug delivery strategy for cancer treatment.