Boron Neutron Capture Therapy with Size-controlled Nanoparticles

Boron neutron capture therapy (BNCT) is emerging cancer therapy requiring neutron radiation and 10B drug. Although BNCT with boronophenylalanine (BPA) is approved clinically in Japan, low tumour selectivity and retentivity result in long-time infusion of high doses. Moreover, BNCT without immunomodulator often fails to elicit strong immunostimulatory effects, preclinically causing high drug dosage used, incomplete tumour regression and limited control of metastatic lesions. Based on our finding of size-controllable mechanochemical synthesis of boron-10 carbide nanoparticles (10B4C NPs), the 50 nm size NPs grafted with poly(glycerol), ¹⁰B₄C(50)-PG, show superior tumour selectivity and retentivity to enhance eradication efficacy at much lower dosage. Antitumour immunity is boosted by ¹⁰B₄C(50)-PG–BNCT without extrinsic immunomodulator to induce abscopal effect treating distant or metastatic tumours.