Dendrimers as Innovative Radiopharmaceuticals in Cancer Radionanotherapy

Abstract

Radiotherapy is one of the most commonly used cancer treatments, with an estimate of 40% success that could be improved further if more efficient targeting and retention of radiation at the tumor site were achieved. This review focuses on the use of dendrimers in radionanotherapy, an emerging technology aimed to improve the efficiency of radiotherapy by implementing nanovectorization, an already established praxis in drug delivery and diagnosis. The labeling of dendrimers with radionuclides also aims to reduce the dose of radiolabeled materials and, hence, their toxicity and tumor resistance. Examples of radiolabeled dendrimers with alpha, beta, and Auger electron emitters are commented, along with the use of dendrimers in boron neutron capture therapy (BNCT). The conjugation of radiolabeled dendrimers to monoclonal antibodies for a more efficient targeting and the application of dendrimers in gene delivery radiotherapy are also covered.

Current outlook on radionuclide delivery systems: from design consideration to translation into clinics

“…Nowadays, the application of dendimers in biomedicine as drug delivery platform is rapidly growing. The design principle of dendrimers, including surface/interior chemistry, size generation, shape, flexibility and composition, has been comprehensively reviewed and described in the work [136]. Various types of dendrimers including polyamidoamine (PAMAM), polypropyleneimine (PPI), poly(glycerol-co-succinic acid), poly- l -lysine (PLL), melamine, triazine, poly(glycerol), poly(2,2-bis(hydroxymethyl)-propionic acid) and PEG, as well as carbohydrate-based and citric-acid-based ones, have been developed as drug delivery platforms [137–140].…”

An Appendix of Radionuclides Used in Targeted Alpha Therapy

“…The disease-targeting vector is the component that will assure the delivery of the radionuclide to the desired cells. Many vectors have been studied over the years such as monoclonal antibodies, peptides, and nanobodies (eg, liposomes, polymers, micelles, and dendrimers) [14,[20][21][22]. When choosing the targeting vector, it is important to consider its biological half-life and how fast the vector will reach the targeted cell compared with the radionuclide half-life.…”

Nano drug delivery systems in upper gastrointestinal cancer therapy

“…Presently, researchers are exploring the concept of dendrimers as radiopharmaceuticals, which combine radiotherapy and gene or antibody delivery [104]. These approaches could enable more efficient targeting and reduce the dose of radioactive materials.…”