| n recent years, high atomic number nanoparticles (NPs) have emerged as promising radioenhancer agents for cancer radiation therapy due to their unique properties. Multi-disciplinary
studies have demonstrated the potential of NPs-based radio-sensitizers to improve cancer
therapy and tumor control at cellular and molecular levels. However, studies have shown that
the dose enhancement effect of the NPs depends on the beam energy, NPs type, NPs size, NPs
concentration, cell lines, and NPs delivery system. It has been believed that radiation dose
enhancement of NPs is due to the three main mechanisms, but the results of some simulation
studies failed to comply well with the experimental findings. Thus, this study aimed to
quantitatively evaluate the physical, chemical, and biological factors of the NPs. An organized
search of PubMed/Medline, Embase, ProQuest, Scopus, Cochrane and Google Scholar was
performed. In total, 77 articles were thoroughly reviewed and analyzed. The studies investigated
44 different cell lines through 70 in-vitro and 4 in-vivo studies. A total of 32 different types of
single or core-shell NPs in different sizes and concentrations have been used in the studies |