Investigation of the bismuth oxide nanoparticles on bystander effect in MCF-7 and hFOB 1.19 cells

This study aims to investigate the effect of bismuth oxide nanoparticles (Bi2O3 NPs) on the radiation induced bystander effect (RIBE) in MCF-7 and hFOB 1.19 cells line. The cells were irradiated with radiation doses of 0 to 12 Gy using 6 MV photon beam in a single exposure. The irradiated cells' culture media were transferred to non-irradiated bystander cells 1 hour post-irradiation. PrestoBlue assay was then performed in this experiment to assess the cells' viability. Results of cell viability percentage in all bystander cell groups compared to the control showed no significant differences (P > 0.05) for both MCF-7 and hFOB 1.19 cell lines. The test also revealed no radiation dose dependencies for all bystander cells groups. The present study demonstrated that MCF-7 and hFOB 1.19 bystander cells were able to proliferate (> 80%) after 48 hours incubation with irradiated-cell conditioned medium (ICCM) treated with Bi2O3 NPs. In summary, the use of Bi2O3 NPs for radiosensitization in radiotherapy is safe and do not increase the RIBE responses in non-targeted cells. RIBE remained as one of the most crucial factors that need to be address and considered for the application of nanoparticles as radiosensitizers in radiotherapy.