TY - JOUR
T1 - In vitro evaluation of two polyhedral boron anion derivatives as linkers for attachment of radioiodine to the anti-HER2 monoclonal antibody trastuzumab
AU - Persson, Mikael
AU - Sivaev, Igor
AU - Winberg, Karl Johan
AU - Gedda, Lars
AU - Malmström, Per Uno
AU - Tolmachev, Vladimir
N1 - Copyright:
Copyright 2009 Elsevier B.V., All rights reserved.
PY - 2007/10/1
Y1 - 2007/10/1
N2 - Improving intracellular retention is important for the use of radiohalogens in radionuclide therapy using internalizing antibodies. Two putative linkers for residualization of radioiodine labels, 7-(4-isothiocyanato-phenyl) undecahydro-7,8-dicarba-nido-undecaborate(1-) ion (NBI) and (4-isothiocyanato- benzylammonio)undecahydro-closo-dodecaborate(1-) (DABI), were analyzed. The anti-HER-2 antibody, trastuzumab, was labeled with iodine-125 using NBI and DABI linkers, and, for comparison, with the para-[125I]iodobenzoate (PIB), and Chloramine-T® (CAT) methods. The different labels were tested for residualizing properties using the HER-2 overexpressing SKBR-3 cells. The cellular radioactivity retention showed that DABI provided a 55% better retention than CAT and was 42% better than PIB after 20 hours. NBI did not improve retention. Accumulation tests up to 21 hours showed that the HER-2-specific accumulation of radioactivity delivered with DABI was, on average, 33% higher than with the use of PIB. These DABI-dependent improvements could, with high probability, be attributed to the good residualizing properties of DABI. The affinity of DABI-labeled trastuzumab to SKBR-3 cells was not better than the affinity of the PIB labeled (3.2 ± 1.9 nM and 0.77 ± 0.39 nM, respectively). In conclusion, the use of the DABI linker improved intracellular retention in vitro in comparison with the other labeling methods.
AB - Improving intracellular retention is important for the use of radiohalogens in radionuclide therapy using internalizing antibodies. Two putative linkers for residualization of radioiodine labels, 7-(4-isothiocyanato-phenyl) undecahydro-7,8-dicarba-nido-undecaborate(1-) ion (NBI) and (4-isothiocyanato- benzylammonio)undecahydro-closo-dodecaborate(1-) (DABI), were analyzed. The anti-HER-2 antibody, trastuzumab, was labeled with iodine-125 using NBI and DABI linkers, and, for comparison, with the para-[125I]iodobenzoate (PIB), and Chloramine-T® (CAT) methods. The different labels were tested for residualizing properties using the HER-2 overexpressing SKBR-3 cells. The cellular radioactivity retention showed that DABI provided a 55% better retention than CAT and was 42% better than PIB after 20 hours. NBI did not improve retention. Accumulation tests up to 21 hours showed that the HER-2-specific accumulation of radioactivity delivered with DABI was, on average, 33% higher than with the use of PIB. These DABI-dependent improvements could, with high probability, be attributed to the good residualizing properties of DABI. The affinity of DABI-labeled trastuzumab to SKBR-3 cells was not better than the affinity of the PIB labeled (3.2 ± 1.9 nM and 0.77 ± 0.39 nM, respectively). In conclusion, the use of the DABI linker improved intracellular retention in vitro in comparison with the other labeling methods.
KW - Antibody
KW - HER-2
KW - Polyhedral boron anion
KW - Radiolabeling
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U2 - 10.1089/cbr.2006.338
DO - 10.1089/cbr.2006.338
M3 - Article
C2 - 17979561
AN - SCOPUS:35848963867
VL - 22
SP - 585
EP - 596
JO - Cancer Biotherapy and Radiopharmaceuticals
JF - Cancer Biotherapy and Radiopharmaceuticals
SN - 1084-9785
IS - 5
ER -