An Activity-Based Near-Infrared Glucuronide Trapping Probe for Imaging β-Glucuronidase Expression in Deep Tissues
- 12 January 2012
- journal article
- Published by American Chemical Society (ACS) in Journal of the American Chemical Society
- Vol. 134 (6), 3103-3110
- https://doi.org/10.1021/ja209335z
Abstract
β-glucuronidase is an attractive reporter and prodrug-converting enzyme. The development of near-IR (NIR) probes for imaging of β-glucuronidase activity would be ideal to allow estimation of reporter expression and for personalized glucuronide prodrug cancer therapy in preclinical studies. However, NIR glucuronide probes are not yet available. In this work, we developed two fluorescent probes for detection of β-glucuronidase activity, one for the NIR range (containing IR-820 dye) and the other for the visible range [containing fluorescein isothiocyanate (FITC)], by utilizing a difluoromethylphenol–glucuronide moiety (TrapG) to trap the fluorochromes in the vicinity of the active enzyme. β-glucuronidase-mediated hydrolysis of the glucuronyl bond of TrapG generates a highly reactive alkylating group that facilitates the attachment of the fluorochrome to nucleophilic moieties located near β-glucuronidase-expressing sites. FITC-TrapG was selectively trapped on purified β-glucuronidase or β-glucuronidase-expressing CT26 cells (CT26/mβG) but not on bovine serum albumin or non-β-glucuronidase-expressing CT26 cells used as controls. β-glucuronidase-activated FITC-TrapG did not interfere with β-glucuronidase activity and could label bystander proteins near β-glucuronidase. Both FITC-TrapG and NIR-TrapG specifically imaged subcutaneous CT26/mβG tumors, but only NIR-TrapG could image CT26/mβG tumors transplanted deep in the liver. Thus NIR-TrapG may provide a valuable tool for visualizing β-glucuronidase activity in vivo.Keywords
This publication has 41 references indexed in Scilit:
- Micro-PET Imaging of β-Glucuronidase Activity by the Hydrophobic Conversion of a Glucuronide ProbeRadiology, 2009
- Antiangiogenesis Targeting Tumor Microenvironment Synergizes Glucuronide Prodrug Antitumor ActivityClinical Cancer Research, 2009
- Gene expression imaging by enzymatic catalysis of a fluorescent probe via membrane-anchored β-glucuronidaseGene Therapy, 2007
- Glucuronides in Anti-Cancer TherapyCurrent Medicinal Chemistry - Anti-Cancer Agents, 2003
- Beta-Glucuronidase-Mediated Drug ReleaseCurrent Pharmaceutical Design, 2002
- Dose Optimization of a Doxorubicin Prodrug (HMR 1826) in Isolated Perfused Human Lungs: Low Tumor pH Promotes Prodrug Activation by β-GlucuronidaseThe Journal of pharmacology and experimental therapeutics, 2002
- Expression and function of β-glucuronidase in pancreatic cancer: potential role in drug targetingNaunyn-Schmiedebergs Archiv für experimentelle Pathologie und Pharmakologie, 2000
- beta-Glucuronidase from Escherichia coli as a gene-fusion marker.Proceedings of the National Academy of Sciences of the United States of America, 1986
- Substrate protection during the fixation of?-glucuronidase: Cytochemical model system studiesJournal of Molecular Histology, 1982
- Naphthol AS-BI (7-bromo-3-hydroxy-2-naphtho-o-anisidine) phosphatase and naphthol AS-BI beta-D-glucuronidase in Chinese hamster ovary cells: biochemical and flow cytometric studies.Journal of Histochemistry & Cytochemistry, 1979