Development of targeted molecular MRI for detection of brain micrometastases

Abstract: Molecular Magnetic Resonance Imaging (mMRI) in preclinical models is an active area of research with the overall goal of visualising specific molecular biomarkers involved in various diseases. Targeted superparamagnetic contrastophores have stimulated a variety of applications in this field. Our lab has successfully been able to detect brain micrometastases by targeting vascular cell-adhesion molecule (VCAM-1) using micron sized particles of iron oxide (MPIO). However, the detection and treatment of brain micrometastases remains challenging since the intact blood-brain barrier (BBB) limits access for both imaging contrast agents and systemic therapies. In this session I will compare sensitivity and specificity of two commonly used iron oxide particles for detection of inflammation in vivo, by applying different MRI sequences and magnetic field strengths. Moreover, I introduce two other inflammation markers, activated leukocyte cell adhesion molecule (ALCAM) and E-selectin as potential biomarkers for detection of brain metastases at early stages. The results support the concept that mMRI may provide a new approach for the early detection of brain metastases, prior to blood-brain barrier breakdown, and could substantially improve diagnosis for patients at risk of secondary progression to the brain.