Boron neutron capture therapy BNCT

One of the most promising appHcations of polyboron hydride chemistry is boron neutron capture therapy (BNCT) for the treatment of cancers (253). Boron-10 is unique among the light elements in that it possesses an unusually high neutron capture nuclear cross section (3.8 x 10 , 0.02—0.05 eV... 

Amine boranes have been examined by a variety of spectroscopic methods (24—29). The boron-substituted alpha-amino acids have been utilized in animal model studies. These compounds along with their precursors and selected derivatives have been shown to possess antineoplastic, antiarthritic, and hypolipidemic activity (30—32). The boron amino acid analogues are also being evaluated for possible utility in boron neutron capture therapy (BNCT) (33). 

The doso-duster containing two carbon atoms, i.e., o-, m- or p-dicarba-doso-dodecaborane C2B10H12, is electronically neutral (see Chapter 3.2). Therefore, the cages are thermally and chemically stable, and extremely hydrophobic. The C2Bio cages are advantageous for boron neutron capture therapy (BNCT) because of their high boron content and ease of chemical transformation. 

Johnsson M, Bergstrnd N, Edwards K. Optimization of drug loading procedures and characterization of liposomal formulations of two novel agents intended for boron neutron capture therapy (BNCT). J Liposome Res 1999 9 53-79. 

In conclusion, boron neutron capture therapy (BNCT) is still in an experimental phase. Although the rationale is particularly attractive (selectivity at the cellular level), it is difficult to draw conclusions from the available clinical data. 

Thirumamagal, B. T. S., Zhao, X. B., Bandyopadhyaya, A. K., et al. (2006) Receptor-targeted liposomal delivery of boron-containing cholesterol mimics for boron neutron capture therapy (BNCT). Bioconjugate Chem. 17, 1141-1150. 

The dual-mechanism of cytotoxic activity of amine-boranes, possessing significant antineoplastic activity and useful also in boron neutron capture therapy (BNCT), initiated the search during recent years for therapeutic compounds of this class which accumulate preferentially in the tumor tissue194,195. The title compound 192, one of the... 

In work that also involves the use of a Mn(III) porphyrin, Huang et al. published a report on the manganese chelate of the tetrakiscarborane carboxylate ester of 2,4-(a, P-dihydroxylethyl)deuteroporphyrin IX (MnBOPP, 9, Figure 2) [19]. The free-base form of this derivative, BOPP, has demonstrated potential as an agent for boron neutron capture therapy (BNCT) [75,76] and photodynamic therapy (PDT) [77] and is known to localize selectively in cerebral glioma tumors at ratios as high as 400 1 relative to normal brain tissue [19,78]. Like the free-base, MnBOPP also selectively localizes in tumor tissue. Specifically, it has been shown to enhance preferentially the... 

The rapid development of carborane chemistry is mainly due to their practical applications. For instance, the potential utility of carborane polymers as gaskets, O-rings, and electrical connector inserts has been reported. Their functionality for solvent extraction of radionuchdes as well as the potential medicinal value of the isoelectronic and isostructural boron analogues of biologically important molecules has been the subject of many review articles. For example, a number of boron compounds have been found to possess anti-inflammatory and antiarthritic activity in animal model studies. Boron compounds have also been implicated in studies designed to probe the importance of the so-called anionic subsite of acetylcholine esterase and Ach receptors. But, by far the most interesting practical apphcations of carboranes are in areas of boron neutron capture therapy (BNCT) and supramolecular assembly. 

Successful treatment of tumors by radiation therapy demands that the dose ratio between tumor tissue and surrounding healthy tissue is greater than unity, and that the radiation dose to the healthy tissue approaches the tolerance dose. This requirement is generally achieved in conventional radiotherapy when applied successfully. It must also be fulfilled in boron neutron capture therapy (BNCT). 

Drechsel, K. Lee, C.S. Leung, E.W. Kane, R.R. Hawthorne, M.F. Synthesis of new building blocks for boron-rich oligomers in boron neutron capture therapy (BNCT). 1. Tetrahedron Lett., 35,6217-6220,1994. 

Kane, R.R. Drechsel, K. Hawthorne, M.F. Automated synthesis of carborane-derived homogeneous oligophosphates Reagents for use in the immunoprotein-mediated boron neutron capture therapy (BNCT) of cancer. J. Am. Chem. Soc., 115, 8853-8854, 1993. 

Boron has two stable isotopes, (80.4% abundance) and °B (19.6%). B has a very high neutron absorption cross section (it is a good absorber of neutrons). This property has been developed for use in the treatment of cancerous tumors in a process called boron neutron capture therapy (BNCT). Boron-containing compounds having a... 

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