Evaluation of 9-[(3-F-18-fluoro-1-hydroxy-2-propoxy)methyl]guanine ([F-18]-FHPG) in vitro and in vivo as a probe for PET imaging of gene incorporation and expression in tumors

Preparation of 9-[(3-F-18-fluoro-1-hydroxy-2-propoxy)methyl]-guanine ([F-18 ]-FHPG) for clinical use, and its evaluation as a positron emission tomogra phy (PET) imaging agent for gene incorporation and expression in tumors are reported. In vitro studies in human colon cancer cells, HT-29, transduced with the retroviral vector G1Tk1SvNa and nontransduced (wild type) showed 4 , 8, 12, and 15 times higher uptake of the probe in 1, 3, 5, and 7 h, respe ctively, in transduced cells compared with the controls. In vivo studies in tumor-bearing nude mice demonstrated that the tumor uptake of the radiotra cer is three and six-fold higher in 2 and 5 h, respectively, in transduced cells compared with the control cells. These results suggest that [F-18]-FH PG is a potential in vivo PET imaging agent for monitoring gene incorporati on and expression in gene therapy of cancer. NUCL MED BIOL 26;4:371-376, 19 99. (C) 1999 Elsevier Science Inc. All rights reserved.