Liposomal neutron capture therapy

Abstract

The cell-killing effect of boron neutron capture therapy (BNCT) is due to the nuclear reaction of two essentially nontoxic species, boron-10 ( 10B) and thermal neutrons, whose destructive effect is well observed in boron-loaded tissues. Therefore, the high accumulation and selective delivery of 10B into the tumor tissue are the most important requirements to achieve efficient neutron capture therapy for cancer. BNCT has been applied clinically for the treatment of malignant brain tumors, malignant melanoma, head and neck cancer, and hepatoma using two boron compounds : sodium borocaptate (10BSH) and L-p-boronoplienylalamine (L-10BPA). These low molecule compounds are easily cleared from the cancer cells and blood, therefore, high accumulation and selective delivery of boron compounds into tumor tissues are most important to achieve effective BNCT and to avoid damage of adjacent healthy cells. Recently, much attention has been focused on liposomal drug delivery system as an attractive intelligent technology of targeting and controlled release of 10B compounds. In this review, recent development of liposomal boron delivery system is summarized.