A new theragnostic approach in the multifunctional radionanomedicine

Theragnostic nanomedicine is a new integrated nanotherapheutic system which can diagnose, deliver targeted therapy and monitor on-line the response to therapy. This multifunctional nanoplatform is an emerging highlight in nanomedicine that combines both diagnostic/imaging and therapeutic aspects, with a great potential for effective cancer imaging and therapy. The multifunctional/theragnostic radionanomedicine would be able to deliver the radionuclide for both imaging and therapy in a targeted manner – encapsulated nanocarriers - to cancer cells and nuclei, to improve the efficacy and safety of both cancer imaging and therapy with the help of a cancer-targeting ligand. Moreover, the development of multifunctional/theragnostic radionanopharmaceuticals is become a possible state-of-the-art in nanomedicine research. Liposomes, dendrimers, quantum dots, iron oxide, nanomicelles, perflurocarbon and carbon nanotubes are commonly used carriers for the development of radionanopharmaceuticals. The radionuclides used in radionanomedicine for therapy are α-particle emitters (Ac-225, At-211 ), β-particle emitters (Cu-67, I-131, Re-186, Re-188, Y-90) and Auger electron emitters (I-125, In-111, At-211 and Ga-67). Radionuclides used for imaging, are γ emitters (In-111, Tc-99m) and electron-particle emitters (Cu-64, F-18, I-124, Y-86, etc.). The aim of this work is to provide an overview of the current status of multifunctional radionanomedicine, and discuss issues to be addressed before exploiting the clinical benefits of radionanopharmaceuticals (radionuclide stability in the nanoradiotracers, radionuclide leakage from nanoradiotracers, possible interactions between the drug and radionuclide, nanoparticles toxicity).