Circular RNA (circRNA) is emerging as a new class of endogenous and regulatory noncoding RNA in recent years. Generally, most circRNAs function as miRNA sponges or transcription/translation regulator to impact the expression of miRNA target genes, which plays important roles in the regulation of cancers. With the widespread application of RNA sequencing (RNA-seq) technology and bioinformatics prediction, large numbers of circRNAs have been identified. However, low abundance expression level of circRNA significantly limits the detection efficiency of RNA-seq.
