%0 Journal Article
%A Morgenroth, Agnieszka
%A Vogg, Andreas T. J.
%A Neumaier, Bernd
%A Mottaghy, Felix M.
%A Zlatopolskiy, Boris D.
%T Radioiodinated indomethacin amide for molecular imaging of cyclooxygenase-2 expressing tumorsinm-5
%J OncoTarget
%V 8
%N 11
%@ 1949-2553
%C [S.l.]
%I Impact Journals LLC
%M FZJ-2017-04114
%P 18059-18069
%D 2017
%X Cyclooxygenase-2 (COX-2) is an important biomarker in several tumors. Available imaging probes display relatively low tumor to background ratios (smaller than 2:1). We evaluated newly developed indomethacin (Ind) derivatives for in vivo molecular imaging of COX-2 expressing carcinoma. Radioiodinated Ind derivatives Ind-NH-(CH2)4-NH-3-[I-125]I-Bz ([I-125]5), Ind-NH-(CH2)4-NH-5-[I-124/125]I-Nic ([I-124/125]6) and Ind-NH-(CH2)4-NH-5-[I-125]I-Iphth ([I-125]7) were prepared from the respective SnBu3-precursors (45–80% radiochemical yield; > 95% radiochemical purity). The cellular uptake of [I-125]5 and [I-125]6 correlated with COX-2 expression determined by SDS page/Western blot analysis. [I-125]5 was predominantly localized in the cell membrane while [I-125]6 was internalized and displayed a diffuse and favorable cytoplasmic distribution. In contrast, [I-125]7 showed only low uptake in COX-2 positive cells. Co-incubation with the COX-2 inhibitor Celecoxib led to an almost complete suppression of cellular uptake of [I-125]5 and [I-125]6. In vivo molecular imaging using positron emission tomography (PET) in SCID mice xenografted with COX-2+ (HT29) and COX-2− (HCT116) human colorectal carcinoma cells was performed for [I-124]6. HT29 xenografts displayed a significantly higher uptake than HCT-116 xenografts (5.6 ± 1.5 vs. 0.5 ± 0.1 kBq/g, P < 0.05) with an extraordinary high tumor to muscle ratio (50.3 ± 1.5). Immunohistological staining correlated with the imaging data. In conclusion, the novel radioiodinated indomethacin derivative ([I-124/125]6) could become a valuable tool for development of molecular imaging probes for visualization of COX-2 expressing tumors.
%F PUB:(DE-HGF)16
%9 Journal Article
%U <Go to ISI:>//WOS:000396877500053
%R 10.18632/oncotarget.15437
%U https://juser.fz-juelich.de/record/834113