Background: Radiotherapy is used as one of the most effective regimens for cancer
treatment, while radioresistance is a major drawback in cancer treatment.
Objectives: This study aimed to evaluate the sensitizing effect of olanzapine (OLA) with X-ray on
glioblastoma (U-87 MG) cells death.
Methods: The synergistic killing effect of OLA with ionizing radiation (IR) on glioma was evaluated
by colony formation assay. The generations of reactive oxygen species (ROS) and protein carbonyl
(PC) as oxidized proteins were determined in OLA-treated and irradiated cells.
Results: Results of this study showed that OLA reduced the number of colonies in irradiated glioma
cells.OLA elevated ROS and PC levels in irradiated cells. The synergistic killing effect of OLA
with IR in U-87 MG cells was observed at concentrations of 1 μM and 20 μM of OLA. The maximum
radiosensitizing effect of OLA was observed at a concentration of 20 μM.
Conclusion: The present study demonstrates that OLA has a radiosensitizing effect on cell death induced
by IR in glioma cells.