Circular RNAs and Exosomes: The New Frontier of Cancer Diagnosis

摘要

Over the last decade, the development of new technologies for genome-wide analyses of the eukaryotic tran-scriptome has allowed comprehensive studies of circRNA species. Although biologists identified circular transcripts more than 20 years ago, these circular molecules were long considered artefacts of aberrant splicing reactions or the prerogative of a few viral pathogens. The evidence from expression data indicates a wide range of more than thousands of endogenous circRNAs in mammalian cells, some of which are abundant, conserved, and stably accumulated within the cell. The functional analysis of these transcripts revealed that circRNAs might regulate microRNA (miRNA) function and suggest that they might act in the regulation of gene expression.Due to their emerging role as gene expression regulators, circRNAs are very likely to become important players in cancer development and pathologies like other types of noncoding RNAs.Moreover, they have shown a great potential as tissue-based markers for cancer classification and prognostication. Recently, it was discovered that circRNAs are secreted through exosomes vesicles; thus, the study of this class of non-coding RNAs has potential implications for therapeutic and research applications.