Biological Evaluation of Boronated Polyamines as Potential Agents for BNCT

The use of BNCT as a cancer treatment modality has been well documented.1,2 The boron-containing delivery agent should be non-toxic, selectively target tumor cells and ideally localize within the nucleus. Various boron-containing analogues of biologically active compounds, such as amino acids, peptides, nucleosides/nucleotides, porphyrins and DNA binder have been synthesized.1 Polyamines, such as spermidine (SPD) and spermine (SPM) are essential for cell growth and cell differentiation in mammals. They interact electrostatically with DNA in a non-specific manner. Their concentration levels are increased in tumor cells, and within such cells, levels are especially high in the nucleus.3,4 In addition, there seems to be a facilitated transport mechanism operative for polyamines into malignant cells.5 For this reason, boron-containing polyamines have been considered as potential BNCT agents.6