Radioiodine based biomedical carriers for cancer theranostics

Theranostics, a promising modern concept combining diagnostic capabilities and therapeutic effects, has been used for optimizing and personalizing the treatment of many entities of cancer. Radionuclide, based on its decay mode, can easily be applied to this field with its imaging properties and cell killing effect. The importance of radioiodine, with a long history in nuclear medicine, in theranostics is indisputable. The commonly used kind of radioiodine in biology and medicine only include iodine-123, iodine-124, iodine-125 and iodine-131. However, the lack of targeting ability of free radioiodine ions to tumor tissue (except for thyroid cancer) and its rapid metabolism significantly limit its application in tumor theranostics. In recent years, great progresses have been made in the development of radioiodine labeled antibodies, nanobodies, peptides, small molecules, nanoparticles, microspheres or hydrogels for tumor theranostics. Moreover, using muti-functional materials as the carriers not only can improve the tumor accumulation and retention of radioiodine, but also provide a platform for combination therapy, resulting in a much more effective effect in specific therapeutic. This paper reviews the design and application of radioiodine labeled biomedical carriers in cancer theranostics.