Imaging Agents in Targeting Tumor Hypoxia

Tissue hypoxia may occur in many diseases, specifically during the occurrence and growth of malignant solid-tumors. Targeting hypoxia is one of the most significant characteristics of tumors in diagnosis, monitoring, and treatment. This review summarizes the current oxygen-sensitive imaging agents used to target tumor hypoxia, including positron-emission computed tomography/single photon-emission computed tomography radionuclide labeled tracers, magnetic resonance imaging contrast agents for hypoxia detection, and hypoxia-sensitive optical imaging probes. Researchers have utilized nanotechnology as a useful toolkit to improve the effects of oxygen-sensitive imaging agents. We emphasize the progress and influence of nanotechnology in these materials and technologies. This review demonstrates that hypoxia imaging agents have promising prospects, and may provide helpful information for tumor diagnosis and prognosis.