About RNAs
The majority of RNA species in eukaryotic cells is comprised of non-coding RNA (ncRNA) rather than messenger RNA (mRNA), and studies have shown that these ncRNAs play a vital role in physiological and developmental processes. Previously, scientists mainly focused on linear ncRNAs, such as long non-coding RNAs (lncRNAs) and micro-RNAs (miRNAs), indicating that these linear ncRNAs have multiple functions in physiological and pathological processes. As a kind of unique circular ncRNA, circular RNAs (circRNAs) have been considered accidental by-products or ‘splicing noise’ with low abundance and little functional potential, resulting from errors during post-transcriptional processing. Now, circRNAs have been recognized and taken seriously in various biological fields. Recent studies have experimentally confirmed the significant biological functions of circRNAs, especially in the field of cancer.
Source: Shang Q et al. The novel roles of circRNAs in human cancer. Mol Cancer. 2019 Jan 9;18(1):6. doi: 10.1186/s12943-018-0934-6