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Review
. 2023 Jun;21(3):289-302.
doi: 10.1007/s11914-023-00786-7. Epub 2023 Apr 29.

Circular RNAs: Promising Targets in Osteoporosis

Sara Reis Moura  1   2   3 , Maria João Fernandes  1   2   3 , Susana G Santos  4   5 , Maria Inês Almeida  1   2   3
Affiliations
Review

Circular RNAs: Promising Targets in Osteoporosis

Sara Reis Moura et al. Curr Osteoporos Rep. 2023 Jun.

Abstract

Purpose of review: Circular RNAs (circRNAs) are RNA transcripts derived from fragments of pre-messenger RNAs through a back-splicing process. An advantage that rises from their circular covalently closed conformation is their high stability, when compared with their linear counterparts. The current review focuses on the emerging roles of circRNAs in osteoporosis, including in osteogenic differentiation and osteoclastogenesis. Their potential as osteoporosis biomarkers will also be discussed.

Recent findings: Although firstly described as non-coding, some of these single-stranded RNAs were recently reported to possess protein-coding capacity. On the other hand, the circRNAs exhibit cell and tissue-specific patterns at the transcriptome level in eukaryotes and are regulated throughout the development or disease progression. Even though thousands of these circular transcripts are listed and annotated, only a limited number of studies describe their biological role in bone processes. Recent evidence indicates inhibitory activator roles in both osteoblasts and osteoclasts differentiation and function. Latest screenings in the blood, plasma, or serum of osteoporosis patients support the potential for circRNA signature to be used as biomarkers in osteoporosis, but further validation is required. While intense research into circRNAs has been detailing their biological roles, there remains a need for standardization and further research to fulfil the future potential of this emerging and highly promising class of regulatory molecules.

Keywords: Bone; Osteoclastogenesis; Osteogenic differentiation; Transcriptome.

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Conflict of interest statement

SRM, MJF, SGS and MIA declare they have no financial interests.

Figures

Fig. 1
Fig. 1
Circular RNAs (circRNAs) in the bone/bone-marrow (left panel) and circulating circRNAs (right panel) in human samples from osteoporotic patients. Red, upregulated; grey, downregulated
See this image and copyright information in PMC

References

    1. Kristensen LS, Jakobsen T, Hager H, Kjems J. The emerging roles of circRNAs in cancer and oncology. Nat Rev Clin Oncol. 2022;19:188–206. doi: 10.1038/s41571-021-00585-y. - DOI - PubMed
    1. Holdt LM, Kohlmaier A, Teupser D. Molecular roles and function of circular RNAs in eukaryotic cells. Cell Mol Life Sci. 2018;75:1071–1098. doi: 10.1007/s00018-017-2688-5. - DOI - PMC - PubMed
    1. Chen L, Huang C, Wang X, Shan G. Circular RNAs in eukaryotic cells. Curr Genomics. 2015;16:312–318. doi: 10.2174/1389202916666150707161554. - DOI - PMC - PubMed
    1. Sanger HL, Klotz G, Riesner D, Gross HJ, Kleinschmidt AK. Viroids are single-stranded covalently closed circular RNA molecules existing as highly base-paired rod-like structures. Proc Natl Acad Sci U S A. 1976;73:3852–3856. doi: 10.1073/pnas.73.11.3852. - DOI - PMC - PubMed
    1. Hsu M-T, Coca-Prados M. Electron microscopic evidence for the circular form of RNA in the cytoplasm of eukaryotic cells. Nature. 1979;280:339–340. doi: 10.1038/280339a0. - DOI - PubMed

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