Protection and Sensitization of Human Cells to Proton Radiation by Cerium Oxide Nanoparticles

Abstract

In radiation therapy for the treatment of cancer, there is demand for novel approaches that will improve tumor cell killing while protecting healthy tissue. One such approach that has shown considerable promise is the application of nanoparticles as radiation sensitizers for tumor cells and as radiation protectants for healthy tissue. In this investigation, cerium oxide nanoparticles (CNPs) obtained from the University of Central Florida's NanoScience Technology Center were studied for their protective effect to charged particle radiation in non-malignant breast cells, and for their sensitizing effect in breast and prostate cancer cell lines. These experiments were conducted at East Carolina University, where human cells were grown in the cell culture facility in the Department of Biology and then irradiated with energetic protons in the Accelerator Laboratory in the Department of Physics. Prior to irradiation, the cells were treated with distinct CNP preparations ranging in concentrations from 10 nanomolar to 10 micromolar, and cell viability was assessed using multiple assays post-irradiation. Radioprotection and radiosensitization were observed for several of the CNP treatments tested. Ultimately, the goal is to find a specific nanoparticle treatment that holds the synergistic effect of enhancing the rate of killing in tumor cells while simultaneously improving the survival of normal cells.