Radiation dose rate affects the radiosensitization of MCF-7 and HeLa cell lines to X-rays induced by dextran-coated iron oxide nanoparticles

Abstract

Background and purpose: The aim of radiotherapy is to deliver lethal damage to cancerous tissue while preserving adjacent normal tissues. Radiation absorbed dose of the tumoral cells can increase when high atomic nanoparticles are present in them during irradiation. Also, the dose rate is an important aspect in radiation effects that determines the biological results of a given dose. This in vitro study investigated the dose-rate effect on the induced radiosensitivity by dextran-coated iron oxide in cancer cells.

Materials and methods: HeLa and MCF-7 cells were cultured in vitro and incubated with different concentrations of dextran-coated iron oxide nanoparticles. They were then irradiated with 6 MV photons at dose rates of 43, 185 and 370 cGy/min. The MTT test was used to obtain the cells’ survival after 48 h of irradiations.

Results: Incubating the cells with the nanoparticles at concentrations of 10, 40 and 80 μg/ml showed no significant cytotoxicity effect. Dextran-coated iron oxide nanoparticles showed more radiosensitivity effect by increasing the dose rate and nanoparticles concentration. Radiosensitization enhancement factors of MCF-7 and HeLa cells at a dose-rate of 370 cGy/min and nanoparticles’ concentration of 80 μg/ml were 1.21 ± 0.06 and 1.19 ± 0.04, respectively.

Conclusion: Increasing the dose rate of 6 MV photons irradiation in MCF-7 and HeLa cells increases the radiosensitization induced by the dextran-coated iron nanoparticles in these cells.

Keywords:

• Radiotherapy
• radiosensitization
• dose rate
• iron oxide nanoparticles
• dextran

Acknowledgements

The authors gratefully acknowledge the research council of Kermanshah University of Medical Sciences (Grant No. 93456) for the financial support. This work was performed in partial fulfillment of the requirements for the master of science degree of Parvaneh Kiani, in the Faculty of Medicine, Kermanshah University of Medical Sciences, Kermanshah, Iran.

Disclosure statement

No potential conflict of interest was reported by the authors.

Notes on contributors

Karim Khoshgard, PhD, is an Assistant Professor of Medical Physics in Faculty of Medicine, Kermanshah University of Medical Sciences, Kermanshah, Iran.

Parvaneh Kiani, MSc, is a Medical Physicist, Kermanshah University of Medical Sciences, Kermanshah, Iran.

Abbas Haghparast, PhD, is an Associated Professor of Medical Physics, and head physicist in Imam Reza Hospital, Kermanshah University of Medical Sciences, Kermanshah, Iran.

Leila Hosseinzadeh, PhD, is an Associated Professor of Toxicology at the Pharmaceutical Research Center, Faculty of Pharmacy, Kermanshah, Iran.

Mohammad Taghi Eivazi, PhD, is an Assistant Professor of Medical Physics in Faculty of Medicine, Kermanshah University of Medical Sciences, Kermanshah, Iran.

Additional information

Funding

This work was supported by the Research Council of Kermanshah University of Medical Sciences [grant number: 93456].