Enhanced radiotherapy efficacy of breast cancer multi cellular tumor spheroids through in-situ fabricated chitosan-zinc oxide bio-nanocomposites as radio-sensitizing agents

Zahra Arab-Bafrani; Erfan Zabihi; Seid Mahdi Jafari; Alireza Khoshbin-Khoshnazar; Elham Mousavi; Mohsen Khalili; Amir Babaei

doi:10.1016/j.ijpharm.2021.120828

Enhanced radiotherapy efficacy of breast cancer multi cellular tumor spheroids through in-situ fabricated chitosan-zinc oxide bio-nanocomposites as radio-sensitizing agents

Int J Pharm. 2021 Aug 10:605:120828. doi: 10.1016/j.ijpharm.2021.120828. Epub 2021 Jun 24.

Authors

Zahra Arab-Bafrani¹, Erfan Zabihi², Seid Mahdi Jafari³, Alireza Khoshbin-Khoshnazar¹, Elham Mousavi⁴, Mohsen Khalili⁵, Amir Babaei⁶

Affiliations

¹ Metabolic Disorders Research Center, Golestan University of Medical Sciences, Gorgan, Iran; Department of Biochemistry and Biophysics, Faculty of Medicine, Golestan University of Medical Sciences, Gorgan, Iran.
² Cancer Research Center, Golestan University of Medical Sciences, Gorgan, Iran; Department of Polymer Engineering, Faculty of Engineering, Golestan University, Gorgan, Iran.
³ Cancer Research Center, Golestan University of Medical Sciences, Gorgan, Iran; Faculty of Food Science and Technology, Gorgan University of Agricultural Sciences and Natural Resources, Gorgan, Iran. Electronic address: smjafari@gau.ac.ir.
⁴ Medical Mycology and Bacteriology Research Center, Kerman University of Medical Sciences, Kerman, Iran; Department of Microbiology and Virology, School of Medicine, Kerman University of Medical Sciences. Kerman, Iran.
⁵ Medical Cellular and Molecular Research Center, Golestan University of Medical Sciences, Gorgan, Iran.
⁶ Department of Polymer Engineering, Faculty of Engineering, Golestan University, Gorgan, Iran.

PMID: 34174360
DOI: 10.1016/j.ijpharm.2021.120828

Abstract

Overwhelming evidence has shown that three-dimensional multicellular tumor spheroids (MCTSs) as a mimic of in-vivo tumor can accurately exhibit cellular responses to treatments. So, we compared the capability of pure zinc oxide nanoparticles (ZnO-NPs) and chitosan-ZnO bio-nanocomposites (CS-ZnO BNCs) for enhancing the radiosensitization of MDA-MB-231 breast cancer cells (BCCs) in the 3D-MCTSs model. ZnO-NPs and CS-ZnO BNCs were synthesized by a facile co-precipitation method. FE-SEM images revealed that the uniform spherical ZnO-NPs with an average diameter of 35 nm were successfully dispersed on chitosan. MDA-MB-231 MCTSs which were formed in a non-adherent culture plate, possessed functional features of in-vivo tumor. The priority of such culture method to conventionally used 2D monolayer (or parental) cell culture is the mimicking of tumor microenvironment. The toxicity of CS-ZnO BNCs and ZnO-NPs against the MDA-M-231 BCCs was evaluated using MTT-colorimetric assay, which demonstrated superior biocompatibility of CS-ZnO BNCs compared to pure ZnO-NPs (even at high concentration of 100 μg/mL). Survival fraction analysis of cells under clinical X-ray irradiation (6 MV) showed that MCTSs had a higher radioresistance compared to parental cells. Besides, the clonogenic potential of irradiated MCTSs was significantly decreased by the addition of CS-ZnO BNCs similar to that of monolayer cells. The sensitivity enhancement ratios (SER) for MCTSs and monolayer cells were calculated 1.5 and 1.63, respectively. Further, tracking of radiobiological properties and apoptosis induction of MCTSs showed that CS-ZnO BNCs not only could lead to the creation of higher radiation-induced complex DNA break and apoptosis death in MCTSs, but also weakened DNA repair mechanisms. It was found that non-toxic concentration of CS-ZnO BNCs has promising potential to enhance radiosensitivity of resistant-MCTSs as a superior in-vitro tumor model. So, CS-ZnO BNCs can be a prominent candidate for overcoming the resistance of BCCs to radiotherapy.

Keywords: Bio-nanocomposites; Breast cancer; Chitosan; Radiosensitizers; ZnO.

MeSH terms

Breast Neoplasms* / drug therapy
Breast Neoplasms* / radiotherapy
Chitosan*
Female
Humans
Nanocomposites*
Nanoparticles*
Tumor Microenvironment
Zinc Oxide*

Substances

Chitosan
Zinc Oxide