The Use of Gadolinium-based Nanoparticles to Improve Radiation Therapy Efficacy in HNSCC

Head and neck squamous cell carcinoma (HNSCC) is an aggressive and recurrent malignancy owing to intrinsic radioresistance and lack of apoptosis induction. Several strategies aiming at radiosensitizing these tumors are currently being developed, one of which relies on the use of high Z elements nanoparticles such as gadolinium. Ultrasmall (5nm) gadolinium-based nanoparticles (GBNs) display properties, including stability, lack of toxicity, renal elimination, preferential accumulation in tumors (EPR effect) which make them a promising radiosensitizing tool. Once delivered to the tumor, GBNs amplify the efficacy of radiotherapy through the generation of secondary electrons leading to the overproduction of reactive oxygen species (ROS).