A novel near-infrared fluorescent probe for monitoring cyclooxygenase-2 in inflammation and tumor.

Targeting cyclooxygenase-2 (COX-2) for molecular imaging is an attractive approach applicable for its overexpression in inflammation and many malignancies. Herein, for monitoring COX-2, we synthesize a specific COX-2 probe celecoxib-MPA probe (CMP), based on celecoxib and a water-soluble near-infrared dye dye ICG-Der-02 (MPA). Its high affinity for binding to COX-2 is verified by molecular docking, dynamics simulation and inhibition assay. At cellular level, CMP selectively accumulates in cytoplasm of COX-2-positive cells. in vivo assays, probe guided-imaging in inflamed or cancerous tissues confirms that CMP can bind to the locally endogenic COX-2 and exhibit intense fluorescence. Importantly, we further prove the targeting specificity of CMP as the fluorescence is significantly reduced by blocking COX-2 active site through preinjection with celecoxib. The results suggest that the probe CMP, with favorable hydrophilic property, good biocompatibility, long-term observation, excellent targeting ability and optical imaging capability, could serve as a promising probe for real-time monitoring COX-2 in inflammation and tumor.