αvβ3 Integrin Receptor Targeting and Near-Infrared Imaging of Solid Tumors Using Surface-Modified Nanoliposomes

Abstract

Abundance of receptors on tumor vasculature presents a prominent target for theranostic applications. The alphavbeta3 integrin receptors expressed on vascular endothelial cells during angiogenesis were therefore considered targets for imaging. Non-invasive visualization of tumor growth and/or delivery systems can appreciate tumor localization and disposition kinetics of carriers, respectively. Herein, we report near-infrared fluorescence imaging (NIRFI) of solid tumors using targeted fluorescence nanoliposomes in vivo. Fluorescence nanoliposomes surface modified with cRGD-peptide were injected into CD1 athymic (nu/nu) mice bearing C6 glioblastoma xenografts (300 mm3). At different time points, mice were subjected to NIRFI for visualization of tumor xenografts and nanocarrier tracing in vivo. NIRFI showed tumor localization of 1,1′-dioctadecyl-3,3,3′,3′-tetramethyl indotricarbocyanine iodide (DiR18)-incorporated-targeted liposomes with maximum tumor-to-tissue occurring at 24-h post-liposome administration. Interaction of integrin receptors with targeted liposomes had contributed to an intense NIRF signal. Molecular studies showed an elevated expression of alphavbeta3 integrin receptors in tumor xenografts. From the studies, it can be concluded that non-invasive localization of tumors and tracing of liposome carriers had been achieved using receptor targeting and NIRFI approaches.