Tumor-Specific ONOO Nanogenerator for Improved Drug Delivery and Enhanced Chemotherapy of Tumor.

Multiple biological barriers in solid tumors severely restrict the penetration of nanomedicines, which is a main cause for therapeutic failure in traditional tumor treatment. Here, a tumor-specific nanogenerator of peroxynitrite (ONOO), prepared by loading cisplatin and sodium nitroprusside into poly(d,l-lactide--glycolide) polymersomes, was designed to improve drug delivery and enhance tumor chemotherapy. After a cascade of nicotinamide adenine dinucleotide phosphate oxidases catalysis and glutathione reduction, the nanogenerator, namely, PMCS, could selectively induce the generation of ONOO in tumor. The generated ONOO could not only strengthen vascular permeability significantly but also improve the accumulation and penetration of PMCS in tumor by activating matrix metalloproteinases-mediated degradation of extracellular matrix. Along with endocytosis, PMCS released cisplatin to induce tumor cell apoptosis. Moreover, free cisplatin liberated from dead cells infected neighboring tumor cells quickly ONOO-mediated up-regulated copper transporter 1, further amplifying chemotherapeutic efficacy. This study advances ONOO as a potent modality to address the main issues of therapeutic delivery, including but not limited to chemotherapy.