Delivery-Graded Programmable Micelles Achieve Enhanced Tumor Starvation through Combined Glutamine Deprivation and Angiogenesis Inhibition.

The inhibition of dependent glutamine metabolism is an effective treatment for triple-negative breast cancer (TNBC) starvation, but it is limited by compensatory glycolysis and inadequate delivery efficiency. Herein, we construct a pH-responsive size/charge-reprogrammed micelle with hierarchical delivery characteristics for TNBC suppression with glutamine depletion and vessel blockade. It consists of a positively charged prodrug micelle chemically grafted with the glutamine transport inhibitor V9302 as the inner core layer, the neovascular disruptor CA4P adsorbed in the middle layer, and a pH-responsive peelable polymer as the outer shell. The nanosystem PPD/PPQV@C could effectively reduce size and reverse charge in response to the tumor acidic microenvironment by removing the outer polymer PPD, as accompanying the release of CA4P. Furthermore, the remaining PPQV could responsively release V9302 in the cytoplasm of tumor cells, improving the bioavailability of cargoes and overcoming permeability barrier through precise hierarchical release strategy. Importantly, V9302 and CA4P localized in the tumor intracellular and extracellular matrix could effectively block TNBC-dependent glutamine metabolism and inhibit compensatory nutrient by blocking angiogenesis, achieving the desired tumor suppression with prolonged survival time. This work exhibits a smart nanoplatform for efficient TNBC treatment via dual blockade of the dependent glutamine metabolism and angiogenesis.