The effect of PPAR-γ agonist on (18)F-FDG PET imaging for differentiating tumors and inflammation lesions.

Introduction: (18)F-2-deoxy-2-fluoro-d-glucose ((18)F-FDG) positron emission tomography (PET) has been used for imaging human cancers for several decades. Despite its extensive use, (18)F-FDG PET imaging has limitations in the tumor findings. The goal of this study was to investigate the potential of a PPAR-γ agonist pioglitazone (PIO) to distinguish tumors and inflammatory lesions in (18)F-FDG PET imaging.

Nonpolymeric surface-coated iron oxide nanoparticles for in vivo molecular imaging: biodegradation, biocompatibility, and multiplatform.

Unlabelled: A new approach to the surface engineering of superparamagnetic iron oxide nanoparticles (SPIONs) may encourage their development for clinical use. In this study, we demonstrated that nonpolymeric surface modification of SPIONs has the potential to be an advanced biocompatible contrast agent for biomedical applications, including diagnostic imaging in vivo.

Methods: Adenosine triphosphate (ATP), which is an innate biomaterial derived from the body, was coated onto the surface of SPIONs.

The effect of mannosylation of liposome-encapsulated indocyanine green on imaging of sentinel lymph node.

The imaging of sentinel lymph nodes (SLN) has been researched for its role in assessing cancer progression and postsurgical lymphedema. Indocyanine green (ICG) is a near-infrared (NIR) optical dye that has been approved by the Food and Drug Administration. It is known that liposome-encapsulated ICG (LP-ICG) has improved stability and fluorescence signal compared with ICG.

In vivo and in vitro evaluation of Cy5.5 conjugated epidermal growth factor receptor binding peptide.

The epidermal growth factor receptor (EGFR) is a tyrosine kinase receptor and plays an important role in carcinogenesis. In this study, the epidermal growth factor receptor binding peptide (EGBP) was identified using a phage display method and evaluated in U87MG cells in order to investigate the possibility to target the EGFR using an optical imaging system. Cyanine dye 5.

Optical imaging of MMP expression and cancer progression in an inflammation-induced colon cancer model.

The purpose of this study was to use a near-infrared (NIR) fluorescent cyclic His-Try-Gly-Phe peptide to characterize and image the expressions of matrix metalloproteinases (MMPs), which are correlated with cancer promotion, in an inflammation-induced colorectal cancer (ICRC) model. We explored the relationship between the development of colon cancer and the expression of MMPs at the same colonic sites in ICRC models. To develop ICRC models, mice were administered a single intraperitoneal dose (10 mg/kg) of azoxymethane (AOM) and exposed orally to 2% dextran sodium sulfate (DSS) for one week.

Dextran-conjugated vascular endothelial growth factor receptor antibody for in vivo melanoma xenografted mouse imaging.

Intact immunoglobulin G antibody has a relatively large molecule size of approximately 150 kDa that remains in the bloodstream for many weeks, which is a considerable disadvantage when it is used to carry radioactive materials for imaging. To lower background activity and increase the contrast of images, we investigated antivascular endothelial growth factor (VEGF) receptor 2 antibody (DC101) conjugated dextran for VEGF receptor 2 imaging in tumor xenografted mice. DTPA-conjugated aminodextran was synthesized, reacted with sulfo-LC-SPDP, and then reacted with DC101.

Effect of molecular imaging on validation of developed anti-hVEGFR2 therapeutic antibody.

Vascular endothelial growth factor receptor type 2 (VEGFR2)-targeted tumor treatment is an antiangiogenic therapeutic strategy. The human sodium iodide symporter (hNIS) gene is a useful reporter gene for tumor imaging and radiotherapy. In this study, we investigated the evaluation of therapeutic efficacy in hNIS gene-transfected tumor xenografts using a gamma imaging system after treatment with an anti-VEGFR2 antibody.

Reduction of stimulated sodium iodide symporter expression by estrogen receptor ligands in breast cancer cells.

Purpose: The sodium iodide symporter (NIS) mediates active iodide uptake in lactating breast tissue, and when its levels are enhanced by all-trans retinoic acid (atRA), NIS has been proposed as a target for the imaging and radiotherapy of breast cancer. Importantly, the estrogen receptor α (ERα) is an important regulator of atRA induced NIS gene expression in breast cancer cells. In this study, we investigated the effect of an ER agonist (17β-estradiol, E(2)) or antagonist [trans-hydroxytamoxifen (TOT) or raloxifene (RAL)] treatment on the regulation of NIS gene expression and iodide uptake in an ERα-positive breast cancer (MCF-7) model.

Oleyl-chitosan nanoparticles based on a dual probe for optical/MR imaging in vivo.

Oleic acid-conjugated chitosan (oleyl-chitosan) is a powerful platform for encapsulating oleic acid-decorated iron oxide nanoparticles (ION), resulting in a good magnetic resonance imaging (MRI) probe. Oleyl-chitosan could self-assemble into core-shell structures in aqueous solution and provide the effective core compartment for loading ION. ION-loaded oleyl-chitosan nanoparticles showed good enhanced MRI sensitivity in a MR scanner.

Evaluation of the therapeutic efficacy of a VEGFR2-blocking antibody using sodium-iodide symporter molecular imaging in a tumor xenograft model.

Purpose: Vascular endothelial growth factor receptor 2-blocking antibody (DC101) has inhibitory effects on tumor growth and angiogenesis in vivo. The human sodium/iodide symporter (hNIS) gene has been shown to be a useful molecular imaging reporter gene. Here, we investigated the evaluation of therapeutic efficacy by molecular imaging in reporter gene transfected tumor xenografts using a gamma imaging system.

Synthesis of N₄'-[¹⁸F]fluoroalkylated ciprofloxacin as a potential bacterial infection imaging agent for PET study.

Syntheses and evaluation of fluoroalkylated ciprofloxacin analogues are described. Among these analogues, N₄'-3-fluoropropylciprofloxacin (16) showed the most efficient antibacterial activity against E. coli strains (DH5α and TOP10) and a high binding affinity for DNA gyrase of bacteria.

Surface engineering of quantum dots for in vivo imaging.

The aim of this study was to investigate the effect of gluconic acid (GA) conjugation on the biodistribution of cysteamine-capped quantum dots (amino-QDots) in vivo. Cadmium selenide/zinc sulfide (CdSe/ZnS) was capped with cysteamine through a thiol exchange method, and different amounts of GA were conjugated to the amine groups of cysteamine via the formation of an amide bond. The emission maxima of the synthesized QDots, the amino-QDots and the GA-conjugated amine-QDots (GA-QDots) were located at 720, 600 and 610 nm, respectively.

Prostate cancer-targeted imaging using magnetofluorescent polymeric nanoparticles functionalized with bombesin.

Purpose: In this work, the aim was to prepare and characterize a magnetofluorescent polymeric nanoparticle for prostate cancer imaging in vivo.

Methods: Glycol chitosan (GC) was chemically modified with N-acetyl histidine (NAHis) as a hydrophobic moiety, and bombesin (BBN) was conjugated to the hydrophobically modified GC for use in targeting gastric-releasing peptide receptors (GRPR) overexpressed in prostate cancer cells. NAHis-GC conjugates were labeled with the near-infrared (NIR) fluorophore Cy5.

In vivo imaging of mesenchymal-epithelial transition factor (c-Met) expression using an optical imaging system.

Mesenchymal-epithelial transition factor (c-Met) is a receptor tyrosine kinase that has been shown to be overexpressed and mutated in a variety of malignancies, such as glioma. We have recently found that an (125)I-radiolabeled Gly-Gly-Gly (GGG)- or 8-aminooctanoic acid (AOC)-containing c-Met binding peptide (cMBP) specifically targets c-Met receptor in vivo and in vitro. In this report, cyanine dye 5.

Superparamagnetic iron oxide nanoparticles-loaded chitosan-linoleic acid nanoparticles as an effective hepatocyte-targeted gene delivery system.

The goal of this study was to develop a gene delivery imaging system that targets hepatocytes to help diagnose and treat various liver diseases. To this end, we prepared superparamagnetic iron oxide nanoparticles (SPIO)-loaded with water-soluble chitosan (WSC)-linoleic acid (LA) nanoparticles (SCLNs) that formed gene complexes capable of localizing specifically to hepatocytes. We confirmed that (99m)Tc-labeled SCLNs delivered into mice via intravenous injection accumulated mainly in the liver using nuclear and magnetic resonance imaging.

Targeted molecular imaging of VEGF receptors overexpressed in ischemic microvasculature using chitosan-DC101 conjugates.

Expression of vascular endothelial growth factor receptors (VEGFRs) increases in ischemic muscles, and thus, VEGFR could potentially be used as marker to detect ischemia. Here, we investigated whether (99m)Tc or Cy5.5-labeled chitosan-DC101 conjugates could identify VEGFR-2 overexpressed in ischemia.

The effect of PPAR-gamma agonist on (18)F-FDG uptake in tumor and macrophages and tumor cells.

Purpose: The peroxisome proliferator-activated receptor-gamma (PPAR-gamma) is a member of the nuclear receptor superfamily of ligand-dependent transcription factors, and its role in adipogenesis and glucose metabolism has been well established. PPAR-gamma agonists have been shown to inhibit many cytokines and to have anti-inflammatory effects. In pathologic conditions, enhanced fluoro-2-deoxy-D-glucose (FDG) uptake is observed not only in malignant tumors but also in inflammatory lesions, and this uptake occurs through the glucose transporter in these cells.

Characterization, biodistribution and small-animal SPECT of I-125-labeled c-Met binding peptide in mice bearing c-Met receptor tyrosine kinase-positive tumor xenografts.

c-Met is a receptor tyrosine kinase involved in tumor cell growth, invasion, metastases and angiogenesis. Overexpression of c-Met is frequently observed in several tumor types. Here, we report the in vitro cell-binding properties and biodistribution and SPECT/CT imaging in glioma (U87MG) xenograft-bearing mice of (125)I-labeled c-Met-binding peptides (cMBPs) including analogs conjugated to amino acid and aliphatic carbon linkers.