RRC ID 18547
Author Arena F, Singh JB, Gianolio E, Stefanìa R, Aime S.
Title β-Gal gene expression MRI reporter in melanoma tumor cells. Design, synthesis, and in vitro and in vivo testing of a Gd(III) containing probe forming a high relaxivity, melanin-like structure upon β-Gal enzymatic activation.
Journal Bioconjug Chem
Abstract The aim of this work is to design and test an MRI probe (Gd-DOTAtyr-gal) able to report on the gene expression of β-galactosidase (β-Gal) in melanoma cells. The probe consists of a Gd-DOTA reporter bearing on its surface a tyrosine-galactose-pyranose functionality that, upon the release of the sugar moiety, readily transforms, in the presence of tyrosinase, into melanin oligomeric/polymeric mixture. The formation of Gd-DOTA-containing melanin oligomers and polymers is accompanied by a marked increase of the water proton relaxation rate. The steps involving the release of the galactose-pyranose group and the formation of the melanin-like structure have been carefully investigated in vitro by relaxometric and UV-vis measurements. Cellular uptake studies of Gd-DOTAtyr-gal by melanoma cells have shown that the probe enters the cells, and it appears not to be confined in endosomal vesicles. Using B16-F10LacZ transfected cells, the fast formation of paramagnetic melanin-Gd(III)-containing species has been assessed by the measurement of increased longitudinal relaxation rates of the cellular pellets suspensions. The in vitro results have been confirmed in in vivo MRI investigations on murine melanoma tumor bearing mice. Upon direct injection of Gd-DOTAtyr-gal, a good contrast is observed after 5 h post injection in B16-F10LacZ tumors, but not in B16-F10 tumors lacking the β-Gal enzyme. Gd-DOTAtyr-gal in combination with tyrosinase introduces a novel approach for the detection of β-Gal expression by MRI in vivo.
Volume 22(12)
Pages 2625-35
Published 2011-12-21
DOI 10.1021/bc200486j
PMID 22035020
MeSH Animals Cell Line, Tumor Enzyme Activation Female Gene Expression Regulation, Neoplastic Heterocyclic Compounds* / chemistry Heterocyclic Compounds* / metabolism Magnetic Resonance Imaging / methods* Melanoma / enzymology* Melanoma / genetics Mice Mice, Inbred C57BL Monophenol Monooxygenase / metabolism Organometallic Compounds* / chemistry Organometallic Compounds* / metabolism beta-Galactosidase / genetics beta-Galactosidase / metabolism*
IF 4.031
Times Cited 37
WOS Category BIOCHEMICAL RESEARCH METHODS CHEMISTRY, ORGANIC BIOCHEMISTRY & MOLECULAR BIOLOGY CHEMISTRY, MULTIDISCIPLINARY
Resource
Human and Animal Cells B16 melanoma/lacZ(RCB1284)