Nanomaterials based on rare-earth fluorides, such as cerium(III) fluoride (CeF₃) and gadolinium-doped (Gd-doped) fluoride nanoparticles, exhibit the ability to modulate oxidative stress, mitochondrial function, and cellular damage, thereby selectively enhancing the radiosensitivity of tumor cells. Previous studies have demonstrated that Gd-based fluoride nanomaterials could possess pronounced radiosensitizing potential accompanied by increased production of reactive oxygen species and radiation-induced apoptosis in cancer cells. In line with these findings, the aim of this study was to evaluate the cytotoxic effects of CeF₃ and CeF₃:Gd (15%) nanoparticles using the XTT viability assay on the human HeLa cell line. The nanoparticles were applied at concentrations of 0.5, 1, 2, 4, and 8 mg/mL, and cell viability assessed following 24 hours of treatment. The results show that CeF₃ induces a mild, dose-dependent reduction in viability (76–87%), indicating low cytotoxicity. In contrast, CeF₃:Gd (15%) nanoparticles exhibit a markedly stronger cytotoxic effect (56–72%), with a linear decline in viability and a substantially lower IC₅₀ value. These findings indicate that gadolinium doping significantly enhances the cytotoxic potential of CeF₃ nanoparticles toward HeLa cells, suggesting that Gd-modified fluoride nanomaterials may represent a more effective platform for the development of antitumor and radiosensitizing agents. The results provide a basis for future studies focusing on the underlying mechanisms of action and the evaluation of combined therapeutic approaches.
Kostic et al. (Wed,) studied this question.