Research Article

Synergistic effect of RAD50 downregulation on combination of rucaparib and doxorubicin

Volume: 62 Number: 2 June 12, 2023
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Synergistic effect of RAD50 downregulation on combination of rucaparib and doxorubicin

Abstract

Aim: The MRN (MRE11-RAD50-NBS1) protein complex functions as a DNA damage sensor and plays essential roles to coordinate the repair of DNA double-strand breaks. Although dysfunctional MRN activity has been shown to sensitize cancer cells to certain DNA-damaging agents or PARP inhibitors, the functional significance of RAD50 upon rucaparib and doxorubicin treatments has yet to be studied. The aim of this research was to investigate the response of RAD50-defective cancer cells toward the combination of rucaparib and doxorubicin. Materials and Methods: Human bone osteosarcoma epithelial cells (U2OS) were used in this study to assess the therapeutic potential of RAD50 expression levels. The RNA interference technology was applied to silence the expression of the RAD50 mRNA activity. The qRT-PCR technique was used to investigate the mRNA expression levels of the relevant genes. Western blotting analysis was conducted to assess the relevant protein expression levels. Clonogenic survival assay was performed to dissect the effect of RAD50-loss on the rucaparib and doxorubicin combination treatment. Results: RAD50 knockdown resulted in a significant decrease in MRE11 and NBS1 protein levels, whereas it did not affect p53 and p21 expressions at mRNA and protein levels. Furthermore, the cells with RAD50-loss had impaired DNA damage response activation against acute doxorubicin treatment. We finally showed that RAD50 depletion increased the cytotoxicity of doxorubicin when combined with the PARP inhibitor rucaparib. Conclusion: Taken together, our preclinical findings suggest that RAD50 expression levels can be explored as a predictive biomarker in the evaluation for precision cancer treatments involving PARP inhibitors.

Keywords

References

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Details

Primary Language

English

Subjects

Health Care Administration

Journal Section

Research Article

Publication Date

June 12, 2023

Submission Date

August 11, 2022

Acceptance Date

December 7, 2022

Published in Issue

Year 2023 Volume: 62 Number: 2

Vancouver
1.Ramazan Gundogdu, Mehmet Kadir Erdoğan, Aydın Sever, Yusuf Toy. Synergistic effect of RAD50 downregulation on combination of rucaparib and doxorubicin. EJM. 2023 Jun. 1;62(2):289-300. doi:10.19161/etd.1160550

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