Dataset Information

Imaging Neurotensin Receptor in Prostate Cancer With ⁶⁴Cu-Labeled Neurotensin Analogs.

ABSTRACT:

Introduction

Neurotensin receptor 1 (NTR-1) is expressed and activated in prostate cancer cells. In this study, we explore the NTR expression in normal mouse tissues and study the positron emission tomography (PET) imaging of NTR in prostate cancer models.

Materials and methods

Three ⁶⁴Cu chelators (1, 4, 7, 10-tetraazacyclododecane-1, 4, 7, 10-tetraacetic acid [DOTA], 1,4,7-triazacyclononane-N,N',N?-triacetic acid [NOTA], or AmBaSar) were conjugated to an NT analog. Neurotensin receptor binding affinity was evaluated using cell binding assay. The imaging profile of radiolabeled probes was compared in well-established NTR⁺ HT-29 tumor model. Stability of the probes was tested. The selected agents were further evaluated in human prostate cancer PC3 xenografts.

Results

All 3 NT conjugates retained the majority of NTR binding affinity. In HT-29 tumor, all agents demonstrated prominent tumor uptake. Although comparable stability was observed, ⁶⁴Cu-NOTA-NT and ⁶⁴Cu-AmBaSar-NT demonstrated improved tumor to background contrast compared with ⁶⁴Cu-DOTA-NT. Positron emission tomography/computed tomography imaging of the NTR expression in PC-3 xenografts showed high tumor uptake of the probes, correlating with the in vitro Western blot results. Blocking experiments further confirmed receptor specificity.

Conclusions

Our results demonstrated that ⁶⁴Cu-labeled neurotensin analogs are promising imaging agents for NTR-positive tumors. These agents may help us identify NTR-positive lesions and predict which patients and individual tumors are likely to respond to novel interventions targeting NTR-1.

SUBMITTER: Deng H

PROVIDER: S-EPMC6081756 | biostudies-literature | 2017 Jan-Dec

REPOSITORIES: biostudies-literature

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Publications

Imaging Neurotensin Receptor in Prostate Cancer With <sup>64</sup>Cu-Labeled Neurotensin Analogs.

Deng Huaifu H Wang Hui H Zhang He H Wang Mengzhe M Giglio Ben B Ma Xiaofen X Jiang Guihua G Yuan Hong H Wu Zhanhong Z Li Zibo Z

Molecular imaging 20170101

<h4>Introduction</h4>Neurotensin receptor 1 (NTR-1) is expressed and activated in prostate cancer cells. In this study, we explore the NTR expression in normal mouse tissues and study the positron emission tomography (PET) imaging of NTR in prostate cancer models.<h4>Materials and methods</h4>Three <sup>64</sup>Cu chelators (1, 4, 7, 10-tetraazacyclododecane-1, 4, 7, 10-tetraacetic acid [DOTA], 1,4,7-triazacyclononane-N,N',N″-triacetic acid [NOTA], or AmBaSar) were conjugated to an NT analog. Ne ...[more]

PMID: 28849698

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Dataset Information

Imaging Neurotensin Receptor in Prostate Cancer With ⁶⁴Cu-Labeled Neurotensin Analogs.

Introduction

Materials and methods

Results

Conclusions

Publications

Imaging Neurotensin Receptor in Prostate Cancer With <sup>64</sup>Cu-Labeled Neurotensin Analogs.

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OmicsDI is part of the ELIXIR infrastructure

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Dataset Information

Imaging Neurotensin Receptor in Prostate Cancer With 64Cu-Labeled Neurotensin Analogs.

Introduction

Materials and methods

Results

Conclusions

Publications

Imaging Neurotensin Receptor in Prostate Cancer With <sup>64</sup>Cu-Labeled Neurotensin Analogs.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets

Imaging Neurotensin Receptor in Prostate Cancer With ⁶⁴Cu-Labeled Neurotensin Analogs.