Tumor‐specific expression and detection of a CEST reporter gene. Issue 2 (27th April 2015)

• Record Type: Journal Article
• Authors: Minn, Il; Bar‐Shir, Amnon; Yarlagadda, Keerthi; Bulte, Jeff W. M.; Fisher, Paul B.; Wang, Hao; Gilad, Assaf A.; Pomper, Martin G.
• Is Part Of: Magnetic resonance in medicine. Volume 74:Issue 2(2015:Aug.)
• Page Start: 544
• Page End: 549
• Publication Date: 2015-04-27
• Subjects: Nuclear magnetic resonance -- Periodicals; Electron paramagnetic resonance -- Periodicals; 616.07548
• DOI: 10.1002/mrm.25748
• Languages: English
• ISSNs: 0740-3194

Abstract

<abstract abstract-type="main"> <title> <x xml:space="preserve">Abstract</x> </title> <sec id="mrm25748-sec-0001" sec-type="section"> <title>Purpose</title> <p>To develop an imaging tool that enables the detection of malignant tissue with enhanced specificity using the exquisite spatial resolution of MRI.</p> </sec> <sec id="mrm25748-sec-0002" sec-type="section"> <title>Methods</title> <p>Two mammalian gene expression vectors were created for the expression of the lysine‐rich protein (LRP) under the control of the cytomegalovirus (CMV) promoter and the progression elevated gene‐3 promoter (PEG‐3 promoter) for constitutive and tumor‐specific expression of LRP, respectively. Using those vectors, stable cell lines of rat 9L glioma, 9L<sup>CMV‐LRP</sup> and 9L<sup>PEG‐LRP</sup>, were established and tested for CEST contrast <italic>in vitro</italic> and <italic>in vivo</italic>.</p> </sec> <sec id="mrm25748-sec-0003" sec-type="section"> <title>Results</title> <p>9L<sup>PEG‐LRP</sup> cells showed increased CEST contrast compared with 9L cells <italic>in vitro</italic>. Both 9L<sup>CMV‐LRP</sup> and 9L<sup>PEG‐LRP</sup> cells were capable of generating tumors in the brains of mice, with a similar growth rate to tumors derived from wild‐type 9L cells. An increase in CEST contrast was clearly visible in tumors derived from both 9L<sup>CMV‐LRP</sup> and 9L<sup>PEG‐LRP</sup> cells at 3.4 ppm.</p> </sec> <sec id="mrm25748-sec-0004" sec-type="section"> <title>Conclusion</title> <p>The PEG‐3 promoter:LRP system can be used as a cancer‐specific, molecular‐genetic imaging reporter system <italic>in vivo</italic>. Because of the ubiquity of MR imaging in clinical practice, sensors of this class can be used to translate molecular‐genetic imaging rapidly. Magn Reson Med 74:544–549, 2015. © 2015 Wiley Periodicals, Inc.</p> </sec> </abstract>