Bone marrow ribonucleotide reductase mRNA levels and methylation status as prognostic factors in patients with myelodysplastic syndrome treated with 5-Azacytidine

Abstract

Ribonucleotide Reductase (RNR) is a two-subunit (RRM1, RRM2) enzyme, responsible for the conversion of ribonucleotides to deoxyribonucleotides required for DNA replication. To evaluate RNR as a biomarker of response to 5-azacytidine, we measured RNR mRNA levels by a quantitative real-time PCR in bone marrow samples of 98 patients with myelodysplastic syndrome (MDS) treated with 5-azacytidine with parallel quantification of the gene promoter’s methylation. Patients with low RRM1 levels had a high RRM1 methylation status (p = 0.005) and a better response to treatment with 5-azacytidine (p = 0.019). A next-generation sequencing for genes of interest in MDS was also carried out in a subset of 61 samples. Splicing factor mutations were correlated with lower RRM1 mRNA levels (p = 0.044). Our results suggest that the expression of RNR is correlated with clinical outcomes, thus its expression could be used as a prognostic factor for response to 5-azacytidine and a possible therapeutic target in MDS.

Keywords:

• Ribonucleotide reductase (RNR)
• myelodysplastic syndrome
• methylation
• 5-azacytidine
• response to treatment

Author contributions

Christina-Nefeli Kontandreopoulou participated in research design, performance of the research, data analysis, and writing of the paper. Panagiotis T. Diamantopoulos participated in data analysis and writing of the paper. Nora-Athina Viniou participated in research design and critically reviewed the final manuscript. Andreas Giannopoulos and Theodoros Loupis participated in the performance of the experiments. The remaining authors participated in the provision of patient samples and data collection.

Acknowledgments

We would like to thank Mr. George Kyriakakis for his valuable help in data collection and digitization.

Ethics approval

Informed consent was obtained in accordance with the Declaration of Helsinki. The study was approved by the Institutional Ethics Committee.

Disclosure statement

All authors have read and approved the manuscript. Panagiotis T. Diamantopoulos reports personal fees for presentations for Roche, Celgene, Janssen-Cilag, Astellas, Amgen, and Novartis. Argiris Symeonidis and Nora Athina Viniou report investigational grants and personal fees for presentations and advisory roles from Celgene/Genesis Pharma. Ioannis Kotsianidis, Vassiliki Pappa, Athanasios Galanopoulos, and Panayiotis Panayiotidis report personal fees for honoraria and advisory roles from Celgene/Genesis Pharma. Maria Dimou reports personal fees for advisory roles from Celgene/Genesis Pharma. The remaining authors declare that they have no conflict of interest.

Data availability statement

Research data are available upon reasonable request.

Additional information

Funding

The study was supported by Genesis Pharma under Grant [GE00036/2018].