Recent Advances in Receptor-Targeted Fluorescent Probes for In Vivo Cancer Imaging

Molecular Imaging Laboratory, Department of Radiology, University of Pittsburgh School of Medicine, 100 Technology Drive Suite 452G, Pittsburgh, PA 15219
Current Medicinal Chemistry (Impact Factor: 3.85). 08/2012; 19(28). DOI: 10.2174/092986712803341467
Source: PubMed


Receptor-targeted optical imaging of cancer is emerging as an attractive strategy for early cancer diagnosis and surgical guidance. The success of such strategy depends largely upon the development of receptor-targeted fluorescent probes with high specificity and binding affinity to the target receptors. Recently, a host of such probes have been reported to target cancer-specific receptors, such as somatostatin receptors (SSTRs), integrin receptors, cholecystokinin-2 (CCK2) receptor, gastrin-releasing peptide (GRP) receptor, endothelin A (ETA) receptor, translocator protein (TSPO) receptor, epidermal growth factor (EGF) receptor, human epidermal growth factor receptor 2 (HER2), vascular endothelial growth factor (VEGF) receptor, folate receptor (FR), transferrin receptor (TFR), low-density lipoprotein (LDL) receptors, type I insulin-like growth factor receptor (IGF1R), vasoactive intestinal peptide (VIP) receptors, urokinase plasminogen activator (uPA) and estrogen receptor (ER). This review will describe the recent advances in synthetic targeting optical imaging probes and demonstrate their in vivo imaging potentials. Moreover, current status of near infrared (NIR) fluorescent dyes, targeting moieties and coupling reactions, as well as strategies for designing targeted probes, will also be discussed.

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Available from: Mingfeng Bai
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    • "Therefore, there is an urgent need to develop reliable imaging tools to answer these important questions about CB 2 R. As a low-cost imaging method with high sensitivity and resolution , fluorescence imaging is widely used to study receptors at the cellular and molecular levels [14e16]. For in vivo imaging studies, near infrared (NIR) light (650e900 nm) is usually adopted, owing to the low tissue absorption and negligible tissue autofluorescence in the NIR region [14]. However, it is difficult to develop CB 2 R-targeted fluorescent probes because conjugating a relatively large fluorescent dye to a CB 2 R ligand could obliterate its binding to CB 2 R [17]. "
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