环状RNA(circularRNAs,circRNAs)是一类非常令人感兴趣的保守单链RNA分子,其通过前体mRNA反向剪接衍生自外显子或内含子序列。与典型的线性RNA不同,circRNAs形成共价闭合,连续的稳定环,没有5'端盖和3'末端聚(A)尾部,因此对外切核酸酶消化有抗性。大多数circRNAs是高度丰富的,并在不同物种中保守,具有组织或发育阶段特异性表达。circRNAs已被证明作为microRNA海绵发挥重要作用,基因剪接和转录的调节因子,RNA结合蛋白海绵和蛋白/肽翻译。新的证据表明,circRNAs在各种人类疾病中起作用,特别是癌症,并可能作为癌症治疗更好的预测生物标志物和治疗靶点。考虑到它们潜在的临床相关性,circRNAs已成为肿瘤病理领域新的研究热点。在本研究中,目前对生物发生的理解,特点,数据库,研究方法,生物学功能亚细胞分布,表观遗传调控,讨论了circRNAs的细胞外运输和降解。特别是,首先总结了circRNA研究中涉及的多个数据库和方法,以及确定circRNAs在肿瘤生长中潜在作用的最新进展,移民和入侵,这使得circRNAs更好的预测生物标志物,被描述。此外,提出了circRNAs在癌症患者管理中的临床应用的未来观点,这可以为将来的circRNAs提供新的见解。
Circular RNAs (circRNAs) are a very interesting class of conserved single-stranded RNA molecules derived from exonic or intronic sequences by precursor mRNA back-splicing. Unlike canonical linear RNAs, circRNAs form covalently closed, continuous stable loops without a 5\'end cap and 3\'end poly(A) tail, and therefore are resistant to exonuclease digestion. The majority of circRNAs are highly abundant, and conserved across different species with a tissue or developmental-stage-specific expression. circRNAs have been shown to play important roles as microRNA sponges, regulators of gene splicing and transcription, RNA-binding protein sponges and protein/peptide translators. Emerging evidence reveals that circRNAs function in various human diseases, particularly cancers, and may function as better predictive biomarkers and therapeutic targets for cancer treatment. In consideration of their potential clinical relevance, circRNAs have become a new research hotspot in the field of tumor pathology. In the present study, the current understanding of the biogenesis, characteristics, databases, research methods, biological functions subcellular distribution, epigenetic regulation, extracellular transport and degradation of circRNAs was discussed. In particular, the multiple databases and methods involved in circRNA research were first summarized, and the recent advances in determining the potential roles of circRNAs in tumor growth, migration and invasion, which render circRNAs better predictive biomarkers, were described. Furthermore, future perspectives for the clinical application of circRNAs in the management of patients with cancer were proposed, which could provide new insights into circRNAs in the future.