A noninvasive reporter system to image adenoviral-mediated gene transfer to ovarian cancer xenografts.
OBJECTIVE
Gene therapy trials for ovarian cancer would benefit from a noninvasive imaging modality to detect the location and extent of gene transfer. The human type 2 somatostatin receptor gene (hSSTr2) was evaluated as a reporter gene for imaging adenoviral (Ad) gene transfer to ovarian cancer.


METHODS
A replication-incompetent Ad vector encoding hSSTr2 (Ad-hSSTr2) was used to infect SKOV3.ip1 cells in vitro and tumors growing in nude mice. Gamma camera imaging detected uptake of 99m-Tc-P2045 (a somatostatin analogue) due to expressed hSSTr2.


RESULTS
Specific uptake of 99m-Tc-P2045 was imaged in Ad-hSSTr2-infected cells in vitro. Noninvasive in vivo imaging detected gene transfer to intraperitoneal tumors. Uptake of 99m-Tc-P2045 (percentage dose per gram of tumor) averaged 2.2 and 0.18 for Ad-hSSTr2-injected mice and controls, respectively.


CONCLUSIONS
This study reports the first noninvasive imaging method for imaging gene transfer to ovarian cancer. A human gene therapy trial is planned.
Chaudhuri
T R
TR
Department of Radiology, University of Alabama at Birmingham, 35294-0012, USA.
Rogers
B E
BE
Buchsbaum
D J
DJ
Mountz
J M
JM
Zinn
K R
KR
D000256:Adenoviridae / Q000235:genetics; D000818:Animals; D005260:Female; D018014:Gene Transfer Techniques; D017930:Genes, Reporter; D005822:Genetic Vectors / Q000096:biosynthesis / Q000235:genetics*; D006801:Humans; D051379:Mice; D008819:Mice, Nude; D015609:Organotechnetium Compounds / Q000493:pharmacokinetics; D010051:Ovarian Neoplasms / Q000000981:diagnostic imaging / Q000235:genetics* / Q000378:metabolism; D011877:Radionuclide Imaging; D019275:Radiopharmaceuticals / Q000493:pharmacokinetics; D017481:Receptors, Somatostatin / Q000096:biosynthesis / Q000235:genetics*; D023041:Xenograft Model Antitumor Assays
D015609:Organotechnetium Compounds; D019275:Radiopharmaceuticals; D017481:Receptors, Somatostatin; C093733:somatostatin receptor 2