摘要

Angiogenesis is necessary for tumor growth, without which a tumor can not grow beyond a few millimeters in diameter. This review summarizes the current status on the research of peptide Arg-Gly-Asp (RGD) and Arg-Arg-Leu (RRL) as well as its derivatives applied in tumor angiogenesis imaging and targeted therapy with single photon emission tomography (SPECT) and positron emission tomography (PET). Peptide RGD sequence Arg-Gly-Asp targeted and combined to integrin alpha(v)beta(3) which has been overexpressed on tumor endothelial cells and many different tumor cells is a robust site for tumor angiogenesis molecular imaging and targeted therapy. The various derivatives of RGD were focused on optimizing its biological characteristics including affinity, targeting efficacy and pharmacokinetics. The other alternative novel tumor angiogenesis molecular imaging agent is RRL peptide which targeted to tumor derived endothelial cells and then applied to visualize tumor angiogenesis with enhanced ultrasonic imaging, optical imaging and SPECT in animal. These novel peptide agents can have promising applications for tumor angiogenesis imaging and antiangiogenic tumor therapy.