Background: Radiation therapy (RT) is a main treatment option for cancer. Due to normal tissue toxicity, radiosensitizers are commonly used to enhance RT. In particular, high-Z nanoparticles, such as gold nanoparticles, have been investigated as radiosensitizers. So far, however, the studies have been focused on gold nanospheres (GNSs). In this study, we assessed the potential of ultra-thin gold nanowires (GNWs) as a radiosensitizer, which is the first time.
Results: Our studies showed that GNWs are superior to GNSs with regard to enhancing radical production under radiation. In vitro analysis found that GNWs could stick to the plasma membrane and elevate lipid peroxidation and intracellular oxidative stress under radiation. When tested in vivo , GNWs led to improved tumor suppression by RT relative to GNSs. GNWs may be gradually reduced to form GNSs and shorter gold nanowires, which benefits repeated radiation.
Conclusions: Our studies suggest that GNWs are as a promising type of radiosensitizer, which can be safely injected into tumors to enhance radiotherapy. While the current study was conducted in breast cancer models, the approach can be extended to the treatment of other cancers.