Boron Neutron Capture Therapy mediated by boric acid combined with electroporation in the hamster cheek pouch oral cancer model

OLAIZ N; GARABALINO, MARCELA A; IARA S SANTA CRUZ; PAULA S RAMOS; AGUSTINA M PORTU; GISELA SAINT MARTIN; MARÍA E ITOIZ; EMILIANO CC POZZI; SILVIA THORP; PAULA CUROTTO; ANDREA MONTI HUGHES; VERÓNICA A TRIVILLIN; GUILLERMO MARSHALL; AMANDA E SCHWINT

Congreso; LXII Reunión científica anual de la sociedad argentina de investigación clínica (SAIC), lxvi reunión anual de la sociedad argentina de inmunología (SAI) y reunión de la sociedad argentina de fisiología (SAF); 2018

BNCT is based on the selective incorporation of 10B carriers in tumor followed by neutron irradiation. The biodistribution of boron carriers in tumor in terms of absolute and relative 10B concentration, retention in tumor, targeting homogeneity and microdistribution conditions the therapeutic efficacy of BNCT. Given that electroporation (EP) can act as a non-specific system to administer anti-tumoral agents, the aim of this study was to evaluate if EP optimizes the delivery of the boron compound Boric Acid (BA), improving the therapeutic efficacy of BNCT in the hamster cheek pouch oral cancer model. Exophytic tumors (Squamous Cell Carcinoma) were induced in the pouch of Syrian hamsters by topical application of the carcinogen dimethyl-benzanthracene (DMBA) twice a week for 3 months. For boron biodistribution and BNCT studies we administered BA (50 mg 10B/kg iv) followed by EP (1000 v/cm, 8 pulses of 100μs) 10 min. post-administration. Three hours after the administration of BA we sacrificed the animals for boron biodistribution studies or performed BNCT/BA studies. We observed a statistically significant increase (p< 0.0001) in boron uptake in tumors corresponding to the protocol BA+EP (4710 ppm) versus control BA without EP (367 ppm) whilst no changes were observed in normal pouch and precancerous tissues. The ongoing studies of BNCT/BA+EP showed a high therapeutic efficacy (94%), similar to that observed with BNCT/BA (84%). However, these results are statistically significant (p