111In-BnDTPA-F3: an Auger electron-emitting radiotherapeutic agent that targets nucleolin.

INTRODUCTION: The F3 peptide (KDEPQRRSARLSAKPAPPKPEPKPKKAPAKK), a fragment of the human high mobility group protein 2, binds nucleolin. Nucleolin is expressed in the nuclei of normal cells but is also expressed on the membrane of some cancer cells. The goal was to investigate the use of 111In-labele...

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Main Authors: Cornelissen, B, Waller, A, Target, C, Kersemans, V, Smart, S, Vallis, K
Format: Journal article
Language:English
Published: SpringerOpen 2012
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author Cornelissen, B
Waller, A
Target, C
Kersemans, V
Smart, S
Vallis, K
author_facet Cornelissen, B
Waller, A
Target, C
Kersemans, V
Smart, S
Vallis, K
author_sort Cornelissen, B
collection OXFORD
description INTRODUCTION: The F3 peptide (KDEPQRRSARLSAKPAPPKPEPKPKKAPAKK), a fragment of the human high mobility group protein 2, binds nucleolin. Nucleolin is expressed in the nuclei of normal cells but is also expressed on the membrane of some cancer cells. The goal was to investigate the use of 111In-labeled F3 peptide for Auger electron-targeted radiotherapy. METHODS: F3 was labeled with fluorescein isothiocyanate (FITC) for confocal microscopy and conjugated to p-SCN-benzyl-diethylenetriaminepentaacetic acid (BnDTPA) for labeling with 111In to form 111In-BnDTPA-F3. MDA-MB-231-H2N (231-H2N) human breast cancer cells were exposed to 111In-BnDTPA-F3 and used in cell fractionation, γH2AX immunostaining (a marker of DNA double-strand breaks), and clonogenic assays. In vivo, biodistribution studies of 111In-BnDTPA-F3 were performed in 231-H2N xenograft-bearing mice. In tumor growth delay studies, 111In-BnDTPA-F3 (3 μg, 6 MBq/μg) was administered intravenously to 231-H2N xenograft-bearing mice once weekly for 3 weeks. RESULTS: Membrane-binding of FITC-F3 was observed in 231-H2N cells, and there was co-localization of FITC-F3 with nucleolin in the nuclei. After exposure of 231-H2N cells to 111In-BnDTPA-F3 for 2 h, 1.7% of 111In added to the medium was membrane-bound. Of the bound 111In, 15% was internalized, and of this, 37% was localized in the nucleus. Exposure of 231-H2N cells to 111In-BnDTPA-F3 (1 μM, 6 MBq/μg) resulted in a dose-dependent increase in γH2AX foci and in a significant reduction of clonogenic survival compared to untreated cells or cells exposed to unlabeled BnDTPA-F3 (46 ± 4.1%, 100 ± 1.8%, and 132 ± 7.7%, respectively). In vivo, tumor uptake of 111In-BnDTPA-F3 (3 μg, 6 MBq/μg) at 3-h post-injection was 1% of the injected dose per gram (%ID/g), and muscle uptake was 0.5%ID/g. In tumor growth delay studies, tumor growth rate was reduced 19-fold compared to untreated or unlabeled BnDTPA-F3-treated mice (p = 0.023). CONCLUSION: 111In-BnDTPA-F3 is internalized into 231-H2N cells and translocates to the nucleus. 111In-BnDTPA-F3 has a potent cytotoxic effect in vitro and an anti-tumor effect in mice bearing 231-H2N xenografts despite modest total tumor accumulation.
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spelling oxford-uuid:74caf8fc-5958-4418-9b6b-456d7c40d26b2022-03-26T20:05:14Z111In-BnDTPA-F3: an Auger electron-emitting radiotherapeutic agent that targets nucleolin.Journal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:74caf8fc-5958-4418-9b6b-456d7c40d26bEnglishSymplectic Elements at OxfordSpringerOpen2012Cornelissen, BWaller, ATarget, CKersemans, VSmart, SVallis, KINTRODUCTION: The F3 peptide (KDEPQRRSARLSAKPAPPKPEPKPKKAPAKK), a fragment of the human high mobility group protein 2, binds nucleolin. Nucleolin is expressed in the nuclei of normal cells but is also expressed on the membrane of some cancer cells. The goal was to investigate the use of 111In-labeled F3 peptide for Auger electron-targeted radiotherapy. METHODS: F3 was labeled with fluorescein isothiocyanate (FITC) for confocal microscopy and conjugated to p-SCN-benzyl-diethylenetriaminepentaacetic acid (BnDTPA) for labeling with 111In to form 111In-BnDTPA-F3. MDA-MB-231-H2N (231-H2N) human breast cancer cells were exposed to 111In-BnDTPA-F3 and used in cell fractionation, γH2AX immunostaining (a marker of DNA double-strand breaks), and clonogenic assays. In vivo, biodistribution studies of 111In-BnDTPA-F3 were performed in 231-H2N xenograft-bearing mice. In tumor growth delay studies, 111In-BnDTPA-F3 (3 μg, 6 MBq/μg) was administered intravenously to 231-H2N xenograft-bearing mice once weekly for 3 weeks. RESULTS: Membrane-binding of FITC-F3 was observed in 231-H2N cells, and there was co-localization of FITC-F3 with nucleolin in the nuclei. After exposure of 231-H2N cells to 111In-BnDTPA-F3 for 2 h, 1.7% of 111In added to the medium was membrane-bound. Of the bound 111In, 15% was internalized, and of this, 37% was localized in the nucleus. Exposure of 231-H2N cells to 111In-BnDTPA-F3 (1 μM, 6 MBq/μg) resulted in a dose-dependent increase in γH2AX foci and in a significant reduction of clonogenic survival compared to untreated cells or cells exposed to unlabeled BnDTPA-F3 (46 ± 4.1%, 100 ± 1.8%, and 132 ± 7.7%, respectively). In vivo, tumor uptake of 111In-BnDTPA-F3 (3 μg, 6 MBq/μg) at 3-h post-injection was 1% of the injected dose per gram (%ID/g), and muscle uptake was 0.5%ID/g. In tumor growth delay studies, tumor growth rate was reduced 19-fold compared to untreated or unlabeled BnDTPA-F3-treated mice (p = 0.023). CONCLUSION: 111In-BnDTPA-F3 is internalized into 231-H2N cells and translocates to the nucleus. 111In-BnDTPA-F3 has a potent cytotoxic effect in vitro and an anti-tumor effect in mice bearing 231-H2N xenografts despite modest total tumor accumulation.
spellingShingle Cornelissen, B
Waller, A
Target, C
Kersemans, V
Smart, S
Vallis, K
111In-BnDTPA-F3: an Auger electron-emitting radiotherapeutic agent that targets nucleolin.
title 111In-BnDTPA-F3: an Auger electron-emitting radiotherapeutic agent that targets nucleolin.
title_full 111In-BnDTPA-F3: an Auger electron-emitting radiotherapeutic agent that targets nucleolin.
title_fullStr 111In-BnDTPA-F3: an Auger electron-emitting radiotherapeutic agent that targets nucleolin.
title_full_unstemmed 111In-BnDTPA-F3: an Auger electron-emitting radiotherapeutic agent that targets nucleolin.
title_short 111In-BnDTPA-F3: an Auger electron-emitting radiotherapeutic agent that targets nucleolin.
title_sort 111in bndtpa f3 an auger electron emitting radiotherapeutic agent that targets nucleolin
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AT targetc 111inbndtpaf3anaugerelectronemittingradiotherapeuticagentthattargetsnucleolin
AT kersemansv 111inbndtpaf3anaugerelectronemittingradiotherapeuticagentthattargetsnucleolin
AT smarts 111inbndtpaf3anaugerelectronemittingradiotherapeuticagentthattargetsnucleolin
AT vallisk 111inbndtpaf3anaugerelectronemittingradiotherapeuticagentthattargetsnucleolin