Tumor-localizing and radiosensitizing properties of meso-tetra(4-nido- carboranylphenyl)porphyrin (H2TCP)
Background and Purpose: Boron Neutron Capture Therapy (BNCT) is a binary cancer treatment that exploits the short range particles released from a nuclear fission reaction involving the non-radioactive 10B nucleus and low-energy neutrons for the destruction of tumor cells. In this perspective, porphyrins and phthalocyanines can represent a vehicle for the transport of significant amounts of boron to the neoplastic lesion. Material and Methods: B16F1 melanotic melanoma subcutaneously transplanted in C57/BL6 mice has been used as an in vivo model. Pharmacokinetic studies were performed by intratumoral and intravenous injection of a meso-substituted porphyrin containing 36 B atoms per molecule (H2TCP) and the distribution of H2TCP in the tumor was assessed by fluorescence microscopy analysis. The tumor-bearing mice were exposed to the radiation field for 20 min at a reactor power of 5 kW. Results: At 0.5 h after intratumoral administration or at 24 h after intravenous injection, the amount of 10B in the tumor was found to be about 60 ppm and about 6 ppm, respectively. In spite of the different amounts of 10B in the tumor at the time of irradiation, a very similar delay in tumor growth (5-6 days) was induced by neutron irradiation in the two groups of injected mice with respect to control mice. Conclusions: Our results demonstrate that a suitable boron-loaded porphyrin displays a significant affinity for subcutaneous tumors, and upon activation by thermal neutrons, can promote an important response even in a fairly aggressive and generally radioresistant tumor such as melanotic melanoma. Copyright © 2008 Society of Porphyrins & Phthalocyanines.
Publication Source (Journal or Book title)
Journal of Porphyrins and Phthalocyanines
Soncin, M., Friso, E., Jori, G., Hao, E., Vicente, M., Miotto, G., Colautti, P., Moro, D., Esposito, J., Rosi, G., & Fabris, C. (2008). Tumor-localizing and radiosensitizing properties of meso-tetra(4-nido- carboranylphenyl)porphyrin (H2TCP). Journal of Porphyrins and Phthalocyanines, 12 (7), 866-873. https://doi.org/10.1142/S1088424608000261