Decoy activity through microRNAs: the therapeutic implications

Abstract

Introduction: microRNAs (miRNAs), small noncoding RNAs, are deregulated in several diseases including cancer. miRNAs regulate gene expression at a posttranscriptional level by binding to 5′UTR, coding regions or 3′UTR of messenger RNAs (mRNA), inhibiting mRNA translation or causing mRNA degradation. The same miRNA can have multiple mRNA targets, and the same mRNA can be regulated by various miRNAs.

Areas covered: Recently, seminal contributions by several groups have implicated miRNAs as components of an RNA–RNA language that involves cross-talk between competing endogenous RNAs through a decoy mechanism. We review the studies that described miRNAs as players in a biological decoy activity. miRNAs can either be trapped by competing endogenous RNAs or interact with proteins that have binding sites for mRNAs.

Expert opinion: The miRNA decoy functions have implications for the design of therapeutic approaches in human diseases, including specific ways to overcome resistance to drug therapy and future miRNA-based clinical trials design.

Keywords::

• mimic
• regulation
• sponge
• therapeutic potential

Acknowledgements

We thank an anonymous reviewer for comments that helped to clarify several concepts described in this review. We also thank Tamara Locke (Department of Scientific Publications, MD Anderson Cancer Center) for her help with the editing of this manuscript.

Declaration of interest

M.I.A. is supported by a PhD fellowship (SFRH/BD/47031/2008) from Fundação para a Ciência e Tecnologia, Portugal. Dr. Calin is The Alan M. Gewirtz Leukemia & Lymphoma Society Scholar. He is also supported as a Fellow at The University of Texas MD Anderson Research Trust, as a University of Texas System Regents Research Scholar, and by the CLL Global Research Foundation. Work in Dr. Calin's laboratory is supported in part by an NIH/NCI grant (CA135444), a Department of Defense Breast Cancer Idea Award, Developmental Research Awards in Breast Cancer, Ovarian Cancer, Brain Cancer, Prostate Cancer, Multiple Myeloma, and Leukemia SPOREs, the Laura and John Arnold Foundation, the RGK Foundation and the Estate of C. G. Johnson, Jr. The authors disclose no conflicts of interests and no funding was received in preparation of this manuscript.

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