Nanoparticles to lower cancer radiation dose
doi:10.1038/nindia.2013.53 Published online 11 April 2013
Researchers have found that if human cancer cells are laced with glucose-capped gold nanoparticles before they undergo radiation therapy, it could significantly reduce the radiation dose needed to kill such malignant cells1. The finding would open new doors in cancer radiation therapy, for which researchers are always seeking new ways to reduce radiation dose and minimize the effect on surrounding normal cells and organs.
Noble metal nanoparticles have been interesting candidates due to their potential applications in diagnostics and therapeutics. The researchers synthesized glucose capped gold nanoparticles (Glu-AuNP) and radio-sensitised HeLa cell lines (human cervix cancer cells) with them. They compared the effect of radiation of these cells with normal Hela cells. They found that the Glu-AuNP treatment resulted in better radiation effect. This was evident from increase in relative biological effectiveness (RBE) values for carbon ion irradiated HeLa cells.
"There is about 30% reduction in radiation dose for 90% cell killing of HeLa cells, when internalized by Glu-AuNPs," Devesh Kumar Avasthi, one of the researchers from the Inter University Accelerator Centre in New Delhi told Nature India.
Why is a reduced radiation dose needed when the nanoparticles are internalized by the cancer cells? Avasthi attributed it to "enhanced radiosensitivity due to the presence of high Z nanoparticles in cancer cells". Radiation in HeLa cells with Au nanoparticles produces larger number of secondary electrons in interaction with high Z matter as opposed to HeLa cells without the nanoparticles.