Hypoxia-Responsive Luminescent CEST MRI Agent forIn VitroandInVivoTumor Detection and Imaging

Hypoxia is a feature of most solid tumors and a keydeterminant of cancer growth and propagation. Sensing hypoxiaeffectively could lead to more favorable clinical outcomes. Here, wereport a molecular antenna-based bimodal probe designed toexploit the complementary advantages of magnetic resonance(MR)- and optical-based imaging. Specifically, we describe thesynthesis and evaluation of a dual-action probe (NO2-Eu) thatpermits hypoxia-activated chemical exchange saturation transfer(CEST) MR and optical imaging. In CT26 cells, thisNO2-Euprobe not only provides an enhanced CEST MRI signal but alsoturnsonthe optical signal under hypoxic conditions. Time-dependentin vivoCEST imaging in a hypoxic CT26 tumorxenograft mouse model revealed probe-dependent tumor detectionby CEST MRI contrast in the tumor area. We thus suggest that dual-action hypoxia probes, like that reported here, could have a roleto play in solid tumor diagnosis and monitoring

Automated summary

A bimodal probe based on molecular antenna was developed for enhanced imaging of solid tumors under hypoxic conditions. The probe exhibited both magnetic resonance and optical signals, allowing for improved tumor detection and monitoring.