CircRNAs: From anonymity to novel regulators of gene expression in cancer (Review)

Harper,Katherine   L.; Mcdonnell,Euan; Whitehouse,Adrian

doi:10.3892/ijo.2019.4904

CircRNAs: From anonymity to novel regulators of gene expression in cancer (Review)

Authors:
- Katherine L. Harper
- Euan Mcdonnell
- Adrian Whitehouse
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Affiliations: School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds, LS2 9JT, UK
Published online on: October 24, 2019 https://doi.org/10.3892/ijo.2019.4904
Pages: 1183-1193

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Abstract

Circular RNAs (circRNAs) are a group of non‑coding RNAs, formed mostly through a unique backsplicing mechanism. Originally proposed to be a by‑product from errors in splicing, recent studies have shown they exhibit a range of roles in regulating gene expression, including sponging of microRNAs (miRNAs), interactions with RNA‑binding proteins and regulation of transcription. Though research is still in its infancy, evidence suggests circRNA levels are tightly regulated in the cell, reinforced by dysregulated circRNAs levels being implicated in a range of diseases, including cancer and viral infection. There is growing interest in circRNAs playing specific roles in cancers, either oncogenic or as tumour suppressors, with particular focus on their potential as novel biomarkers. This review will provide an overview of circRNA biogenesis and regulation, and their potential roles in the cell, with a focus on their dysregulation in cancer.

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