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Synthesis and investigation of a radioiodinated F3 peptide analog as a SPECT tumor imaging radioligand.

ABSTRACT: A radioiodinated derivative of the tumor-homing F3 peptide, (N-(2-{3-[(125)I]Iodobenzoyl}aminoethyl)maleimide-F3Cys peptide, [(125)I]IBMF3 was developed for investigation as a SPECT tumor imaging radioligand. For this purpose, we custom synthesized a modified F3 peptide analog (F3Cys) incorporating a C-terminal cysteine residue for site-specific attachment of a radioiodinated maleimide conjugating group. Initial proof-of-concept Fluorescence studies conducted with AlexaFluor 532 C(5) maleimide-labeled F3Cys showed distinct membrane and nuclear localization of F3Cys in MDA-MB-435 cells. Additionally, F3Cys conjugated with NIR fluorochrome AlexaFluor 647 C(2) maleimide demonstrated high tumor specific uptake in melanoma cancer MDA-MB-435 and lung cancer A549 xenografts in nude mice whereas a similarly labeled control peptide did not show any tumor uptake. These results were also confirmed by ex vivo tissue analysis. No-carrier-added [(125)I]IBMF3 was synthesized by a radioiododestannylation approach in 73% overall radiochemical yield. In vitro cell uptake studies conducted with [(125)I]IBMF3 displayed a 5-fold increase in its cell uptake at 4 h when compared to controls. SPECT imaging studies with [(125)I]IBMF3 in tumor bearing nude mice showed clear visualization of MDA-MB-435 xenografts on systemic administration. These studies demonstrate a potential utility of F3 peptide-based radioligands for tumor imaging with PET or SPECT techniques.

SUBMITTER: Bhojani MS

PROVIDER: S-EPMC3139646 | biostudies-literature | 2011

REPOSITORIES: biostudies-literature

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Synthesis and investigation of a radioiodinated F3 peptide analog as a SPECT tumor imaging radioligand.

Bhojani Mahaveer S MS Ranga Rajesh R Luker Gary D GD Rehemtulla Alnawaz A Ross Brian D BD Van Dort Marcian E ME

PloS one 20110719 7

A radioiodinated derivative of the tumor-homing F3 peptide, (N-(2-{3-[(125)I]Iodobenzoyl}aminoethyl)maleimide-F3Cys peptide, [(125)I]IBMF3 was developed for investigation as a SPECT tumor imaging radioligand. For this purpose, we custom synthesized a modified F3 peptide analog (F3Cys) incorporating a C-terminal cysteine residue for site-specific attachment of a radioiodinated maleimide conjugating group. Initial proof-of-concept Fluorescence studies conducted with AlexaFluor 532 C(5) maleimide-l ...[more]

PMID: 21811604

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Dataset Information

Synthesis and investigation of a radioiodinated F3 peptide analog as a SPECT tumor imaging radioligand.

Publications

Synthesis and investigation of a radioiodinated F3 peptide analog as a SPECT tumor imaging radioligand.

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