Light-assisted hierarchical intratumoral penetration and programmed antitumor therapy based on tumor microenvironment...

The anticancer performance of nanomedicine is largely impeded by insufficient intratumoral penetration. Herein, tumor microenvironment (TME)-amendatory and self-adaptive nanoclusters (NCs) capable of cancer-associated fibroblasts (CAFs) depletion and size/charge conversion were engineered to mediate light-assisted, hierarchical intratumoral penetration. Particularly, large-sized NCs (~50 nm) were prepared via self-assembly of FAP-α-targeting peptide-modified, ¹O₂-sensitive polymers, which were further used to envelope small-sized dendrimer (~5 nm) conjugated with Ce6 and loaded with DOX (DC/D). After systemic administration, the NCs efficiently targeted CAFs and generated lethal levels of ¹O₂ upon light irradiation, which depleted CAFs and concomitantly dissociated the NCs to liberate small-sized, positively charged DC/D. Such stroma attenuation and NCs transformation collectively facilitated the delivery of DC/D into deeper regions of CAF-rich tumors, where DOX and ¹O₂ provoked synergistic anti-cancer efficacies. This study provides an effective approach to facilitate the tumor penetration of nanomedicine by concurrently and spatiotemporally reconfiguring the nano-properties and remodeling the TME.