title: Application of RGD-containing peptides as imaging probes for alphavbeta3 expression.
abstract: Integrin alphavbeta3 plays a pivotale role in tumor angiogenesis and is a receptor for the extracellular matrix proteins with the exposed arginine-glysine-aspartic acid (RGD) tripeptide sequence (e.g. vitronectin, fibronectin). Alphavbeta3 is overexpressed on activated endothelial cells during tumor-induced angiogenesis, whereas it is absent on quiescent endothelial cells and normal tissues. Furthermore, alphavbeta3 is expressed on various tumor cell lines. Due to this restricted expression of alphavbeta3 in tumors, alphavbeta3 is considered a suitable receptor for tumor targeting. In the past decade, several RGD-containing peptide antagonists have been evaluated for monitoring alphavbeta3 expression using SPECT, PET, MRI, OI and US. Molecular imaging tracers for this integrin receptor could be used to noninvasively visualize alphavbeta3 expression in tumors. Noninvasive determination of alphavbeta3 expression potentially can be used to monitor treatment response to antiangiogenic drugs or even to select patients likely to respond to treatment with antiangiogenic drugs. In this review a brief overview on the currently used RGD-containing peptides as imaging probes for noninvasive visualization of alphavbeta3 expression using PET, SPECT, MRI, OI and US is given.
authors.affiliation: Technische Universitat Munchen, Department of Nuclear Medicine, Klinikum rechts der Isar, 81675 Munchen, Germany.
authors.forename: Ingrid
authors.initials: I
authors.lastname: Dijkgraaf
authors.forename: Ambros J
authors.initials: AJ
authors.lastname: Beer
authors.forename: Hans-Jurgen
authors.initials: HJ
authors.lastname: Wester
mesh_terms: D000818:Animals; D006801:Humans; D039302:Integrin alphaVbeta3 / Q000378:metabolism*; D008279:Magnetic Resonance Imaging; D051379:Mice; D015335:Molecular Probes; D009369:Neoplasms / Q000175:diagnosis / Q000000981:diagnostic imaging; D009842:Oligopeptides; D049268:Positron-Emission Tomography; D014463:Ultrasonography
chemical_list: D039302:Integrin alphaVbeta3; D015335:Molecular Probes; D009842:Oligopeptides; C047981:arginyl-glycyl-aspartic acid