Locally unlocks prodrugs by radiopharmaceutical in tumor for cancer therapy

Chemotherapy is the first-line treatment for cancer, but its systemic toxicity can be severe. Tumor-selective prodrug activation offers promising opportunities to reduce systemic toxicity. Here, we present a strategy for activating prodrugs using radiopharmaceuticals. This strategy enables the targeted release of chemotherapeutic agents due to the high tumor-targeting capability of radiopharmaceuticals. [¹⁸F]FDG (2-[¹⁸F]-fluoro-2-deoxy-D-glucose), one of the most widely used radiopharmaceuticals in clinics, can trigger Pt(IV) complex for controlled release of axial ligands in tumors, it might be mediated by hydrated electrons generated by water radiolysis resulting from the decay of radionuclide ¹⁸F. Its application offers the controlled release of fluorogenic probes and prodrugs in living cells and tumor-bearing mice. Of note, an OxaliPt(IV) linker is designed to construct an [¹⁸F]FDG-activated antibody-drug conjugate (Pt-ADC). Sequential injection of Pt-ADC and [¹⁸F]FDG efficiently releases the toxin in the tumor and remarkably suppresses the tumor growth. Radiotherapy is booming as a perturbing tool for prodrug activation, and we find that [¹⁸F]FDG is capable of deprotecting various radiotherapy-removable protecting groups (RPGs). Our results suggest that tumor-selective radiopharmaceutical may function as a trigger, for developing innovative prodrug activation strategies with enhanced tumor selectivity.