Current Limitations of Molecular Magnetic Resonance Imaging for Tumors as Evaluated With High-Relaxivity CD105-Specific Iron Oxide Nanoparticles

Abstract

The accumulation of CD105-specific SPIOs in F9 mouse teratomas was robust. However, visualization of the specifically accumulated SPIOs by MRI was not reliable because of its limited signal detection sensitivity. We postulate that it will be challenging to improve the imaging properties of targeted SPIOs further. Therefore, molecular MRI by targeted SPIOs is currently not suitable for clinical tumor imaging using routinely applicable sequences and field strength.

Magnetite nanoparticles for cancer diagnosis, treatment, and treatment monitoring: recent advances

“…SPION-labeled dendritic cells showed potential for clinical use in assessing the therapeutic efficacy of dendritic cells by providing a visualization of their localization, thereby informing the relative effective dosage that was received and that the appropriate delivery site was accessed. Other studies have monitored the biodistribution and pharmacokinetic behavior of SPIONs in vivo using MRI as the NPs move throughout various organ systems 62–64 . This technique shows the non-invasive tracking capability of magnetite NPs as drugs move to the desired target.…”

A comprehensive literatures update of clinical researches of superparamagnetic resonance iron oxide nanoparticles for magnetic resonance imaging

“…In the review article on Iron oxide-loaded nanotheranostics, Schleich et al (6) asked, why do so many papers describe nanomedicines while only a few nanomedicines are commercialized? Dassler and colleagues at the CT and MR Contrast Media Research division of Bayer Pharma AG (Berlin, Germany) investigated the minimum requirements for obtaining sensitive molecular MRI for use in tumor evaluations under optimal conditions (7). The well-vascularized F9 teratocarcinoma tumor model, which exhibits high levels of the highly accessible target CD105 (endoglin, a glycoprotein which is involved in the angiogenesis process), was used to demonstrate the accumulation and visualization of target-specific SPIOs by MRI.…”

“…However, visualization of the specifically accumulated SPIOs by MRI was not reliable because of its limited signal detection sensitivity. They further postulate that molecular MRI by targeted SPIOs is not suitable for clinical tumor imaging using currently available clinical 3.0-T MRI technology (7).…”

Early Tumor Development Captured Through Nondestructive, High Resolution Differential Phase Contrast X-ray Imaging

“…Whole-body imaging techniques, i.e., magnetic resonance imaging (MRI), X rays, computed tomography (CT), etc., can cover the entire tissue and tumor, but these are limited in their resolution or sensitivity, respectively, with best case typically around 1 × 1 × 1 mm (11–14). In a basic research environment microMRI devices are able to detect better resolution up to 20–40 µm for both ex vivo and in vivo (15, 16). Although this technique provides high resolution it remains limited by low spatial resolution.…”