tetramethylrhodamine and Lung-Neoplasms

The objective of this study was to develop and evaluate an alpha(v)beta(3)-specific nanoprobe consisting of fluorescent superparamagnetic polymeric micelles (FSPPM) for in vivo imaging of tumor angiogenesis. Spherical micelles were produced using poly(ethylene glycol)-b-poly(d,l-lactide) co-polymers conjugated with tetramethylrhodamine, a fluorescent dye, and loaded with superparamagnetic iron oxide nanoparticles. The resulting micelle diameter was 50-70 nm by dynamic light scattering and transmission electron microscopy measurements. Micelles were encoded with an alpha(v)beta(3)-specific peptide, cyclic RGDfK, and optimized for maximum fluorescence and targeting in alpha(v)beta(3)-overexpressing cells in vitro. In mice, cRGD-FSPPM-treated animals showed alpha(v)beta(3)-specific FSPPM accumulation in human lung cancer subcutaneous tumor xenografts. Together with the histological validation, the three-dimensional gradient echo magnetic resonance imaging (MRI) data provide high spatial resolution mapping and quantification of angiogenic vasculature in an animal tumor model using targeted, ultrasensitive MRI nanoprobes.

Topics: Animals; Female; Ferrosoferric Oxide; Fluorescent Dyes; Humans; Integrin alphaVbeta3; Lung Neoplasms; Magnetic Resonance Imaging; Magnetics; Metal Nanoparticles; Mice; Mice, Nude; Micelles; Microscopy, Electron, Transmission; Molecular Imaging; Neoplasms; Neovascularization, Pathologic; Peptides, Cyclic; Polyesters; Rhodamines; Scattering, Radiation; Xenograft Model Antitumor Assays