Efficient Boron Neutron Capture Therapy for Brain Tumor with Novel Boron Carrier
Published:06 Aug.2023 Source:Tokyo Institute of Technology
BNCT exploits the high affinity of boron-10 (10B) atoms for low-energy neutrons. When 10B absorbs a neutron, nuclear reactions release high-energy particles that damage the nearby biological tissue. Therefore, an essential requirement in BNCT is to achieve a significantly higher concentration of 10B in tumor cells than that in healthy normal cells. However, this has proven to be challenging, resulting in low survival rates and limited use of BNCT. Against this backdrop, a research team including Professor Hiroyuki Nakamura from Tokyo Institute of Technology (Tokyo Tech) has developed a novel boron agent that shows great promise for BNCT.
PBC-IP binds non-covalently to naturally present albumin, which allows it to directly interact with tumor cells, promoting its cellular uptake. Thus, the acid moiety can enhance the blood retention of the boron agent, thereby potentially reducing the required dose.The researchers conducted several experiments to confirm the viability of PBC-IP for BNCT, finding that it accumulated in GBM cell cultures 10-20 times more than L-4-boronophenylalanine (BPA), a clinically approved boron agent in Japan. These promising results were also replicated in vivo, both in GBM xenograft models and rat glioma models. PBC-IP administered via convection-enhanced delivery (CED) in the rat model achieved tumor-to-normal brain and tumor-to-blood boron ratios of 37.8 and 94.6, respectively, three hours after completion of CED.
Overall, the proposed boron agent may represent a breakthrough in radiotherapy for GBM, with the researchers currently conducting preclinical studies.