Subcellular boron-10 localization in glioblastoma for boron neutron capture therapy with Na2B12H11SH

Abstract
Because of the short range of the highly energetic particles helium-4 and lithium-7 that results from neutron-induced disintegration of boron-10, the efficacy of Boron Neutron Capture Therapy (BNCT) is heavily dependent on 10B-microlocation. Despite the crucial importance of boron-10, there is little specific information with regard to the agent currently used for inducing BNCT, namely Na2B12H11SH. In the present study, a subcellular 10B-location was investigated in tumor tissue obtained from seven patients with glioblastoma World Health Organization Grade IV. These patients received Na2B12H11SH at doses used in therapeutic trials (75 mg/kg body weight in five patients, and 150 mg/kg body weight in two patients, respectively). In three cases, boron-10 was identified in glioblastoma cells by laser microprobe mass analysis. In these tumors, boron-10 was found only in the nuclei of neoplastic cells but not in other cell compartments. These preliminary results suggest a predominant association of Na2B12H11SH with the nuclei of malignant glioma cells and thus support the value of Na2B12H11SH as a suitable boron carrier for BNCT.