Abscopal effect of boron neutron capture therapy (BNCT): proof of principle in an experimental model of colon cancer

作者：Trivillin Veronica A; Pozzi Emiliano C C; Colombo Lucas L; Thorp Silvia I; Garabalino Marcela A; Monti Hughes Andrea; Gonzalez Sara J; Farias Ruben O; Curotto Paula; Santa Cruz Gustavo A; Carando Daniel G; Schwint Amanda E^*

来源：Radiation and Environmental Biophysics, 2017, 56(4): 365-375.

DOI：10.1007/s00411-017-0704-7

• Boron neutron capture therapy
• BNCT
• Abscopal effect
• Boronophenylalanine (BPA)
• Nuclear reactor RA-3

The aim of the present study was to evaluate, for the first time, the abscopal effect of boron neutron capture therapy (BNCT). Twenty-six BDIX rats were inoculated subcutaneously with 1 x 10(6) DHD/K12/TRb syngeneic colon cancer cells in the right hind flank. Three weeks post-inoculation, the right leg of 12 rats bearing the tumor nodule was treated with BPA-BNCT (BPA-Boronophenylalanine) at the RA-3 nuclear reactor located in Buenos Aires, Argentina, at an absorbed dose of 7.5 Gy to skin as the dose-limiting tissue. The remaining group of 14 tumor-bearing rats were left untreated and used as control. Two weeks post-BNCT, 1 x 10(6) DHD/K12/TRb cells were injected subcutaneously in the contralateral left hind flank of each of the 26 BDIX rats. Tumor volume in both legs was measured weekly for 7 weeks to determine response to BNCT in the right leg and to assess a potential influence of BNCT in the right leg on tumor development in the left leg. Within the BNCT group, a statistically significant reduction was observed in contralateral left tumor volume in animals whose right leg tumor responded to BNCT (post-treatment/pre-treatment tumor volume <1) versus animals who failed to respond (post/pre >= 1), i.e., 13 +/- 15 vs 271 +/- 128 mm(3). In addition, a statistically significant reduction in contralateral left leg tumor volume was observed in BNCT-responsive animals (post/pre <1) vs untreated animals, i.e., 13 +/- 15 vs 254 +/- 251 mm(3). The present study performed in a simple animal model provides proof of principle that the positive response of a tumor to BNCT is capable of inducing an abscopal effect.

• 出版日期2017-11