Roles of Circular RNAs And Their Interactions With MicroRNAs in Human Disorders

Circular RNAs (circRNAs) are a class of non-coding RNAs (ncRNAs) that are involved in transcriptional and posttranscriptional gene expression regulation by sponging microRNAs (miRNAs). As miRNAs control a large set of biological processes, circRNA sponge activity also affects these pathways and thereby participates in human disease initiation and development. A growing number of works have confirmed that circRNAs may play critical roles in normal human tissues and organ functions and in the pathogenesis of human diseases, mainly by interacting with miRNAs. Herein, we review the expressions and functions of circRNAs in diverse disorders, including those of the nervous system and cardiovascular system, cancer, and other common diseases. As circRNAs are easily detected in many clinical samples, they present great potential as biomarkers for disease diagnosis and prognostic evaluation; thus, the prospect of using circRNAs as biomarkers for clinical decision-making is also discussed.