miR-3059-3p Regulates Glioblastoma Multiforme Radiosensitivity Enhancement through the Homologous Recombination Pathway of DNA Repair

Yu-Wen Cheng; Chien-Ju Lin; Shih-Hsun Kuo; Ann-Shung Lieu; Chee-Yin Chai; Hung-Pei Tsai; Aij-Lie Kwan

doi:10.1155/2022/7250278

miR-3059-3p Regulates Glioblastoma Multiforme Radiosensitivity Enhancement through the Homologous Recombination Pathway of DNA Repair

J Oncol. 2022 Sep 21:2022:7250278. doi: 10.1155/2022/7250278. eCollection 2022.

Authors

Yu-Wen Cheng^{1

2}, Chien-Ju Lin³, Shih-Hsun Kuo⁴, Ann-Shung Lieu^{5

6}, Chee-Yin Chai^{2

7

8}, Hung-Pei Tsai⁵, Aij-Lie Kwan^{2

5

6

9}

Affiliations

¹ Department of Neurosurgery, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan.
² Graduate Institute of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan.
³ School of Pharmacy, College of Pharmacy, Kaohsiung Medical University, Kaohsiung, Taiwan.
⁴ Department of Radiation Oncology, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan.
⁵ Division of Neurosurgery, Department of Surgery, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan.
⁶ Department of Surgery, School of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan.
⁷ Department of Pathology, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan.
⁸ Department of Pathology, School of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan.
⁹ Department of Neurosurgery, University of Virginia, Charlottesville, VA, USA.

Abstract

Background: Glioblastoma multiforme (GBM) is one of the most deadly and recalcitrant illnesses of the neurocentral nervous system in humans. MicroRNAs (miRNAs) are a class of noncoding RNAs that play important roles in the regulation of gene expression and biological processes, including radiosensitivity. In this study, we demonstrated the relationship between miR-3059-3p and radiation in GBM.

Materials and methods: Radioresistant (RR) cells were obtained by exposing GBM8401 cells to 80 Gy radiation in 20 weekly 4 Gy fractions. miR-3059-3p mRNA and DNA replication helicase/nuclease 2 (DNA2) protein expressions were detected using real-time polymerase chain reaction and immunoblotting. Using flow cytometry, colony formation and apoptosis were identified using miR-3059-3p mimic, miR-3059-3p inhibitor, DNA2 siRNA, and DNA2 plasmid. Immunoblotting was used to detect DNA repair proteins.

Results: Low levels of miR-3059-3p and high levels of DNA2 were observed in RR cells. Colony formation and apoptosis assays revealed that miR-3059-3p targeted DNA2 to regulate radioresistance. Immunoblotting revealed that miR-3059-3p regulated the homologous recombination (HR) pathway (Rad51 and Rad52) but not the nonhomologous end joining pathway (ku70 and ku80).

Conclusion: Downregulation of DNA2 via miR-3059-3p enhanced the radiosensitivity of GBM cells through the inhibition of the HR pathway.