AUTHOR=Turchinovich Andrey , Samatov Timur R., Tonevitsky Alexander G., Burwinkel Barbara TITLE=Circulating miRNAs: cell–cell communication function? JOURNAL=Frontiers in Genetics VOLUME=Volume 4 - 2013 YEAR=2013 URL=https://www.frontiersin.org/journals/genetics/articles/10.3389/fgene.2013.00119 DOI=10.3389/fgene.2013.00119 ISSN=1664-8021 ABSTRACT=Nuclease resistant extracellular miRNAs have been found in all known biological fluids. The biological function of extracellular miRNAs remains questionable; however, strong evidence suggests that these miRNAs can be more than just byproducts of cellular activity. Some extracellular miRNA species might carry cell-cell signaling function during various physiological and pathological processes. In this review, we discuss the state-of-the-art in the field of intercellular miRNA transport and highlight current theories regarding the origin and the biological function of extracellular miRNAs.