Systematic study of enhanced cytotoxicity effects of gold-based nanoparticles in targeted cancer radiotherapy

Worldwide, cancers are the leading causes of human mortality. To successfully treat advanced-stage cancers, it is important to increase cytotoxicity of targeted tumor cells while reducing side effects on normal cells during radiotherapy. Nanotechnology provides a promising solution to achieve this targeted treatment^[1-3]. An ideal strategy is to develop effective nanoscale radio-sensitizers targeting specifically at tumor cells. In this paper, we focus on gold-based nanoparticles as radio-sensitizers. Naked gold nanoparticles (GNPs) can accumulate at tumor tissues based on passively targeting mechanism and thus it can be used as a radio-sensitizer to kill cancers. However, GNPs conjugated with tumor-specific ligands are more promising for tumor diagnosis and treatment at the molecular scale. We have designed glucose-capped GNPs (or Glu-GNPs) to achieve specific targeting. Our preliminary results show a remarkable increase in cell-uptake of Glu-GNPs and also a significant increase of radiation cytotoxicity after applying irradiations.