Nanoscintillator-photosensitizer conjugate for X-ray induced photodynamic therapy : in vitro studies

The aim of this proposal is to study the ability of radioluminescent nanoparticles (nanoscintillators) to potentiate synchrotron radiotherapy by inducing deep-tissue photodynamic therapy (PDT) and radiation dose-enhancement effect (RDE). While the RDE effect results from an excess of energy deposited by photo- and Auger electrons that are created when X-rays interact with heavy-elements, PDT relies on photosensitizers (PS) that generate cytotoxic species upon light activation. As light penetrates weakly in tissues, PDT is usually limited to superficial tumors. To reach deep tumors, nanoscintillators can be used to locally convert X-rays into visible light and remotely induce PDT. In this project, we will investigate the ability of a nanoscintillator (Lu3Al5O12:Pr) conjugated to a clinically used PS (protoporphyrin IX, PpIX) to induce a PDT and RDE effect in vitro in 2D and 3D cultures of pancreatic tumors.