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Circular RNAs and exosomes in cancer: a mysterious connection

Abstract

Circular RNAs (CircRNAs) are a type of non-coding RNAs (NcRNAs) with a closed annular structure. Until next-generation sequencing (NGS) is developed, the misunderstanding of circRNAs ‘splicing error’ has changed, and the mysterious veil of circRNAs has been revealed. NGS provides an approach to investigate circRNAs. Many scholars point out that circRNAs may play an important role in many diseases, especially cancer. At the same time, exosomes, as a kind of extracellular vesicles loaded with many contents, are a hotspot in recent years. They can act as ‘messengers’ between cells, especially in cancer. Lately, it is interesting circRNAs are enriched and stable in exosomes, also called exo-circRNAs, and there have been several articles on circRNAs associated with exosomes. In this review, we summarize the characteristics of circRNAs, especially its main functions. Then, we briefly introduce exosomes and their function in cancer. Finally, the known relation between circRNAs and exosomes is discussed. With further researches, exo-circRNAs may be a novel pathway for cancer diagnosis and targeted therapy.

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Acknowledgments

We thank the members of our laboratory for support and advice. Jun-chen Hou and Wen Jiang contributed equally to this work and should be considered co-first authors.

Funding

This research was supported by the National Program on Key Research Project (No. 2016YFC0905900), Medical Training Programme Foundation for the Talents by Jiangsu Provincial Department of health (No. 17 [2016]), the 333 Talent Project of Jiangsu Province, top-level (No. 4 [2016]), the National key clinical specialist construction Programs of China (No. 544 [2013]), Natural Science Foundation of Jiangsu Province (No. BK20151579), A Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD, JX10231802), the Key Research Program for the Social Development of Jiangsu Province, China (BE2015718) and the National Natural Science Foundation of China (grant number 81602551).

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Hou, J., Jiang, W., Zhu, L. et al. Circular RNAs and exosomes in cancer: a mysterious connection. Clin Transl Oncol 20, 1109–1116 (2018). https://doi.org/10.1007/s12094-018-1839-y

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Keywords

  • Circular RNAs
  • CircRNAs
  • Exosomes
  • Extracellular vesicles
  • Non-coding RNAs
  • Cancer