Zhao Shikang, Li Shuo, Liu Wei, Wang Yanye, Li Xiongfei, Zhu Shuai, Lei Xi, Xu Song
Department of Lung Cancer Surgery, Tianjin Medical University General Hospital, Tianjin, China.
Tianjin Key Laboratory of Lung Cancer Metastasis and Tumor Microenvironment, Lung Cancer Institute, Tianjin Medical University General Hospital, Tianjin, China.
Front Oncol. 2020 Oct 9;10:523342. doi: 10.3389/fonc.2020.523342. eCollection 2020.
Circular RNAs (circRNAs) are a class of endogenous non-coding RNAs (ncRNAs) with a structure of covalently closed continuous loops, which can regulate gene expression by acting as a microRNA sponge or through other mechanisms. Recent studies have identified that the expression of candidate circRNAs are dysregulated in various tumors and hence are considered as promising diagnostic or therapeutic targets across cancer types. However, the expression and function of circRNAs in lung adenocarcinoma (LUAD) remains unclear. In this article, we investigated the expression of circRNAs in LUAD via MiOncoCirc, which is the first and comprehensive database characterizing circRNAs across >2,000 cancer samples using an exome capture RNA sequencing. We identified seven abnormally expressed circRNAs in LUAD, including circCDR1-AS, circHIPK3, circFNDC3B, circPCMTD1, circRHOBTB3, circFAM13B, and circMAN1A2, as well as conducted a literature review about the function and features of these circRNAs. Previous studies have demonstrated that circCDR1-AS, circMAN1A2, and circHIPK3 were upregulated and significantly correlated with a poor survival, or promoted the tumor progression in lung cancer, whereas other circRNAs have not been fully explored. Besides, we reviewed all the publications regarding circRNAs and LUAD, and noticed that the dysregulation of these circRNAs impacts the development of LUAD through a variety of regulatory mechanisms. In conclusion, the underlying mechanisms of aberrant expression and functions of circRNAs in LUAD are worthy of being further investigated.
环状RNA（circRNAs）是一类内源性非编码RNA（ncRNAs），具有共价闭合连续环的结构，可通过充当微小RNA海绵或通过其他机制来调节基因表达。最近的研究发现，候选circRNAs的表达在各种肿瘤中失调，因此被认为是跨癌症类型有前景的诊断或治疗靶点。然而，circRNAs在肺腺癌（LUAD）中的表达和功能仍不清楚。在本文中，我们通过MiOncoCirc研究了LUAD中circRNAs的表达，MiOncoCirc是第一个也是最全面的数据库，它使用外显子捕获RNA测序对超过2000个癌症样本中的circRNAs进行了表征。我们在LUAD中鉴定出7种异常表达的circRNAs，包括circCDR1-AS、circHIPK3、circFNDC3B、circPCMTD1、circRHOBTB3、circFAM13B和circMAN1A2，并对这些circRNAs的功能和特征进行了文献综述。先前的研究表明，circCDR1-AS、circMAN1A2和circHIPK3在肺癌中上调且与较差的生存率显著相关，或促进肿瘤进展，而其他circRNAs尚未得到充分研究。此外，我们回顾了所有关于circRNAs和LUAD的出版物，并注意到这些circRNAs的失调通过多种调控机制影响LUAD的发展。总之，circRNAs在LUAD中异常表达和功能的潜在机制值得进一步研究。
