PT - JOURNAL ARTICLE AU - Raphael Boisgard AU - Bertrand Kuhnast AU - Benoit Jego AU - Karine Siquier AU - Francoise Hinnen AU - Frederic Dolle AU - Matthias Friebe AU - Sandra Borkowski AU - Ludger Dinkelborg AU - Bertrand Tavitian TI - In vivo PET tumour imaging using an [F-18] labelled aptamer targeting tenascin-C DP - 2009 May 01 TA - Journal of Nuclear Medicine PG - 1594--1594 VI - 50 IP - supplement 2 4099 - http://jnm.snmjournals.org/content/50/supplement_2/1594.short 4100 - http://jnm.snmjournals.org/content/50/supplement_2/1594.full SO - J Nucl Med2009 May 01; 50 AB - 1594 Objectives Tenascin-C is an extracellular matrix adhesion modulating protein, highly expressed in the microenvironment of numerous solid tumors. High tenascin-C expression reduces the prognosis of disease-free survival in patients with several cancers. Previous human studies displayed significant uptake of [Tc-99m]TTA1, a tenascin-C targeting aptamer, in a variety of solid tumours such as lung, breast and brain malignancies Methods Here we labelled TTA1 with fluorine-18 for PET imaging using 1-[3-(2-[18F]-fluoropyridin-3-yloxy)propyl]pyrrole-2,5-dione. Whole body biodistributions and pharmacokinetics of [18F]TTA1 were evaluated in Wistar rats and in nu/nu mice bearing U251 human glioblastoma tumors Results In both species, the main routes of body elimination of [18F]TTA1 were the urinary tract and the hepato enteric route. Blood radioactivity, derived from heart time activity curves, demonstrated vascular persistence of this aptamer with a half life of elimination of 20 min in rats. Tumoral uptake was rapid with a maximum observed 15 min after injection, corresponding to 1.7 +/- 0.6 % of ID/cc, and decreasing to 0.9 +/- 0.4 % at 90 min. In comparison, muscular uptake reached 0.7 +/- 0.2 % of ID/cc at 15 min and 0.17 +/- 0.06 % of ID/cc at 90 min post injection, yielding a tumor-to-muscle ratio of 2.3 and 5.4 at 15 and 90 min, respectively Conclusions This first application of an aptamer for PET imaging is encouraging and may open the possibility of in vivo tumoral characterisation of tenascin-C in solid tumors Research Support Supported by EMIL (European Molecular Imaging Laboratories) EU contract LSH-2004-503569