Radiolabeling and Biological Evaluation of Novel ^99mTc-Nitrido and ^99mTc-Oxo Complexes with 4-Methoxy-_{<span style="font-variant: small-caps">L</span>}-Phenylalanine Dithiocarbamate for Tumor Imaging

• Main Authors: Guangxing Yin (Author), Qing Ruan (Author), Yuhao Jiang (Author), Junbo Zhang (Author)
• Format: Book
• Published: MDPI AG, 2022-10-01T00:00:00Z.
• Subjects: article
• Online Access: Connect to this object online.

Summary

To develop novel radiolabeled amino acid tumor imaging agents, 4-methoxy-_{<span style="font-variant: small-caps;">L</span>}-phenylalanine dithiocarbamate (MOPADTC) was synthesized successfully, and two kinds of ^99mTc-labeled complexes ([^99mTc]TcN-MOPADTC and [^99mTc]TcO-MOPADTC) with high radiochemical purities (RCP > 95%) were obtained. The in vitro stability and partition coefficient were determined, and the results show that both of these complexes have good in vitro stability; [^99mTc]TcO-MOPADTC is hydrophilic, while [^99mTc]TcN-MOPADTC is slightly lipophilic. The biodistribution of [^99mTc]TcN-MOPADTC and [^99mTc]TcO-MOPADTC in mice bearing S180 tumors shows that the tumor uptake and tumor/muscle ratio of [^99mTc]TcO-MOPADTC were higher than the tumor uptake and tumor/muscle ratio of [^99mTc]TcN-MOPADTC. In addition, the tumor retention of [^99mTc]TcO-MOPADTC is better than the tumor retention of [^99mTc]TcN-MOPADTC. A competitive inhibition assay was performed, and the results indicate that [^99mTc]TcO-MOPADTC may enter cells primarily via the _L-alanine/_L-serine/_L-cysteine (ASC) system. Single-photon emission computed tomography (SPECT) imaging of [^99mTc]TcO-MOPADTC shows obvious accumulation in tumor sites, suggesting that [^99mTc]TcO-MOPADTC is a novel potential tumor-imaging agent.

Item Description

10.3390/pharmaceutics14102196
1999-4923