Syntheses and preliminary evaluation of [18F]AlF ‐NOTA‐G‐TMTP1 for PET imaging of high aggressive hepatocellular carcinoma

The goal of this study is to evaluate a new 18F‐labeled imaging agent for diagnosing high metastatic (aggressive) hepatocellular carcinoma using positron emission tomography (PET). The new 18F‐labeled imaging agent [18F]AlF‐NOTA‐G‐TMTP1 was synthesized and radiolabeled with 18F using NOTA‐AlF chelation method. The tumor‐targeting characteristics of [18F]AlF‐NOTA‐G‐TMTP1 was assessed in HepG2, SMCC‐7721, HCC97L and HCCLM3 xenografts. The total synthesis time was about 20 min with radiochemical yield of 25 ± 6%. The specific activity was about 11.1–14.8 GBq/µmol at the end of synthesis based on the amount of peptide used and the amount of radioactivity trapped on the C18 column. The log P value of [18F]AlF‐NOTA‐G‐TMTP1 was ‐3.166 ± 0.022. [18F]AlF‐NOTA‐G‐TMTP1 accumulated in SMCC‐7721 and HCCLM3 tumors (high metastatic potential) in vivo and result in tumor/muscle (T/M) ratios of 4.5 ± 0.3 and 4.7 ± 0.2 (n = 4) as measured by PET at 40 min post‐injection (p.i.). Meanwhile, the tumor/muscle (T/M) ratios of HepG2 and HCC97L tumors (low metastatic potential) were1.6 ± 0.3 and 1.8 ± 0.4. The tumor uptake of [18F]AlF‐NOTA‐G‐TMTP1 could be inhibited 61.9% and 57.6% by unlabeled G‐TMTP1 in SMCC‐7721 and HCCLM3 xenografts at 40 min p.i., respectively. Furthermore, [18F]AlF‐NOTA‐G‐TMTP1 showed pretty low activity in the liver and intestines in all tumor bearing mice, such in vivo distrib...
Source: Contrast Media and Molecular Imaging - Category: Radiology Authors: Tags: Full paper Source Type: research