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A Putative Single-Photon Emission CT Imaging Tracer for Erythropoietin-Producing Hepatocellular A2 Receptor.

ABSTRACT: Erythropoietin-producing hepatocellular (Eph) receptors are receptor tyrosine kinases involved in cell-cell contact. The EphA2 receptor is associated with cancer proliferation and migration. Therefore, EphA2 receptor imaging has the potential for cancer diagnosis. Here, we synthesized N-(5-((4-((4-ethylpiperazin-1-yl)methyl)-3-(trifluoromethyl)phenyl)carbamoyl)-2-methylphenyl)-5-[¹²³I]iodonicotinamide ([¹²³I]ETB) and evaluated it as an imaging tracer for single-photon emission computed tomography (SPECT) imaging of the EphA2 receptor. [¹²³I]ETB was designed on the basis of ALW-II-41-27, an inhibitor of EphA2 receptor kinase. Nonradioactive ETB was also synthesized and has been shown to efficiently inhibit EphA2 receptor kinase activity in vitro (IC₅₀: ETB, 90.2 ± 18.9 nM). A cell-binding assay demonstrated that [¹²⁵I]ETB binds specifically to the EphA2 receptor. The ex vivo biodistribution study of [¹²⁵I]ETB in U87MG tumor-bearing mice also revealed tumor uptake (2.2% ID/g at 240 min). In addition, [¹²³I]ETB uptake in tumors was visualized via SPECT/CT imaging. On the basis of the above, [¹²³I]ETB can be considered a potential SPECT imaging tracer for the EphA2 receptor.

SUBMITTER: Furukawa T

PROVIDER: S-EPMC8365995 | biostudies-literature | 2021 Aug

REPOSITORIES: biostudies-literature

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A Putative Single-Photon Emission CT Imaging Tracer for Erythropoietin-Producing Hepatocellular A2 Receptor.

Furukawa Takenori T Kimura Hiroyuki H Torimoto Hanae H Yagi Yusuke Y Kawashima Hidekazu H Arimitsu Kenji K Yasui Hiroyuki H

ACS medicinal chemistry letters 20210714 8

Erythropoietin-producing hepatocellular (Eph) receptors are receptor tyrosine kinases involved in cell-cell contact. The EphA2 receptor is associated with cancer proliferation and migration. Therefore, EphA2 receptor imaging has the potential for cancer diagnosis. Here, we synthesized N-(5-((4-((4-ethylpiperazin-1-yl)methyl)-3-(trifluoromethyl)phenyl)carbamoyl)-2-methylphenyl)-5-[123I]iodonicotinamide ([123I]ETB) and evaluated it as an imaging tracer for single-photo ...[more]

PMID: 34413953

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Dataset Information

A Putative Single-Photon Emission CT Imaging Tracer for Erythropoietin-Producing Hepatocellular A2 Receptor.

Publications

A Putative Single-Photon Emission CT Imaging Tracer for Erythropoietin-Producing Hepatocellular A2 Receptor.

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