In Situ Generated Novel 1H MRI Reporter for β-Galactosidase Activity Detection and Visualization in Living Tumor Cells

For wide applications of the lacZ gene in cellular/molecular biology, small animal investigations, and clinical assessments, the improvement of noninvasive imaging approaches to precisely assay gene expression has garnered much attention. In this study, we investigate a novel molecular platform in which alizarin 2- O -β- d -galactopyranoside AZ-1 acts as a lacZ gene/β-gal responsive 1 H-MRI probe to induce significant 1 H-MRI contrast changes in relaxation times T 1 and T 2 in situ as a concerted effect for the discovery of β-gal activity with the exposure of Fe 3+ . We also demonstrate the capability of this strategy for detecting β-gal activity with lacZ -transfected human MCF7 breast and PC3 prostate cancer cells by reaction-enhanced 1 H-MRI T 1 and T 2 relaxation mapping.