Evaluation of 99mTc-probestin for imaging APN expressing tumors by SPECT.
Aminopeptidase N (APN) is known to play important roles in tumor angiogenesis, tumor cell invasion, and metastasis. Thus, APN is an attractive biomarker for imaging tumor angiogenesis. Here we report results obtained from biodistribution and single photon emission computed tomography (SPECT) imaging studies of a technetium-99m labeled probestin (a potent APN inhibitor) conjugate containing a tripeptide, Asp-DAP-Cys (DAP=2,3-diaminopropionic acid), chelator and a 8-amino-3,6-dioxaoctanoic acid (PEG2) linker conducted in nude mice xenografted with HT-1080 human fibrosarcoma tumors (APN-positive tumors). These results collectively demonstrate that (99m)Tc-probestin uptake by tumors and other APN expressing tissues in vivo is specific and validate the use of probestin as a vector for targeting APN in vivo.
Department of Pharmaceutical Sciences, College of Pharmacy, The University of Oklahoma Health Sciences Center, Oklahoma City, OK 73117, USA.
Gopal
G
Pathuri
Andria F
AF
Hedrick
Vibhudutta
V
Awasthi
Michael A
MA
Ihnat
Hariprasad
H
Gali
D000818:Animals; D018826:CD13 Antigens / Q000032:analysis* / Q000096:biosynthesis / Q000378:metabolism; D045744:Cell Line, Tumor; D005354:Fibrosarcoma / Q000378:metabolism*; D006801:Humans; D051379:Mice; D008815:Mice, Inbred Strains; D008819:Mice, Nude; D057054:Molecular Imaging / Q000379:methods*; D015394:Molecular Structure; D009374:Neoplasms, Experimental / Q000378:metabolism; D009842:Oligopeptides / Q000737:chemistry; D013667:Technetium / Q000737:chemistry; D015899:Tomography, Emission-Computed, Single-Photon
D009842:Oligopeptides; C063432:probestin; D013667:Technetium; D018826:CD13 Antigens
Aminopeptidase N (APN); CD13; Imaging; N(3)S chelator; Probestin; SPECT; Tc-99m; Tumor angiogenesis