Cancer Detection Using a PET Tracer, 11C-Glycylsarcosine, Targeted to H+/Peptide Transporter

• DOI: 10.2967/jnumed.107.048231
• Publication Date: 2008-03-15T01:41:13Z
• Authors: Keisuke Mitsuoka; Sosuke Miyoshi; Yukio Kato; Yoshihiro Murakami; Rie Utsumi; Yoshiyuki Kubo; Akihiro Noda; Yukio Nakamura; Shintaro Nishimura; Akira Tsuji
• Keywords: Male; 0301 basic medicine; Symporters; Dipeptides; Neoplasms, Experimental; Immunohistochemistry; Peptide Transporter 1; 3. Good health; Mice; 03 medical and health sciences; Fluorodeoxyglucose F18; Cell Line, Tumor; Positron-Emission Tomography; Animals; Tissue Distribution; Carbon Radioisotopes

H⁺/peptide transporter, PEPT1, is functionally expressed in some human cancer cell lines and might be a candidate molecular target for detection of cancers vivo using PET. The aim the present study was to establish novel tumor-imaging technology PET tracer targeted transporter(s). We also compared with ¹⁸F-FDG, focusing on specificity their accumulation between tumor inflammatory tissues. <b>Methods:</b> A dipeptide tracer, ¹¹C-glycylsarcosine (¹¹C-Gly-Sar), injected intravenously into athymic mice transplanted pancreatic, prostate, gastric cells. distribution patterns ¹¹C-Gly-Sar ¹⁸F-FDG tumor-bearing mice, tissue, were assessed by imaging positron planar system (PPIS). Tissue distributions radioactivity measured. expression levels PEPT1 PEPT2 (PEPTs) proteins xenografts tissue examined immunohistochemical analysis. messenger RNA PEPTs 58 available quantified means real-time polymerase chain reaction. <b>Results:</b> All 3 well visualized PPIS after injection ¹¹C-Gly-Sar. Expression those confirmed Tumor-to-blood concentration ratios increased time-dependent manner much higher than unity. Most found recovered as intact tracer. These results indicated that taken up xenografts. It noteworthy minimally tissues no or protein, whereas highly accumulated, values selectivity index being &gt;25.1 0.72 respectively. mRNAs 27.6% 93.1%, respectively, study. <b>Conclusion:</b> indicates promising agent superior distinguishing tumors tissue. Because ubiquitously various types cells examined, could useful many cancers.