Exosome and Exosomal MicroRNA: Trafficking, Sorting, and Function

Abstract

Exosomes are 40–100 nm nano-sized vesicles that are released from many cell types into the extracellular space. Such vesicles are widely distributed in various body fluids. Recently, mRNAs and microRNAs (miRNAs) have been identified in exosomes, which can be taken up by neighboring or distant cells and subsequently modulate recipient cells. This suggests an active sorting mechanism of exosomal miRNAs, since the miRNA profiles of exosomes may differ from those of the parent cells. Exosomal miRNAs play an important role in disease progression, and can stimulate angiogenesis and facilitate metastasis in cancers. In this review, we will introduce the origin and the trafficking of exosomes between cells, display current research on the sorting mechanism of exosomal miRNAs, and briefly describe how exosomes and their miRNAs function in recipient cells. Finally, we will discuss the potential applications of these miRNA-containing vesicles in clinical settings.

Intimate cross-talk between cancer cells and the tumor microenvironment of B-cell lymphomas: The key role of exosomes

“…The exact mechanism of how exosomes communicate with target cells is not yet clear. Based on in vitro studies, it is proposed that exosomes might mediate distant intercellular communication through membrane fusion, 36 endocytosis, 37 or receptor-mediated internalization. [38][39][40] In addition, accumulating evidence points out a new mechanism that exosomes burst and release their contents to regulate the recipient cells, similar to a paracrine mechanism.…”

Critical issues in the clinical application of liquid biopsy in non-small cell lung cancer

“…They contain proteins, lipids, DNA, mRNA, microRNAs and other non-coding RNAs, and are thought to be involved in cell communication and metastasis (24,25). There is growing interest towards these nanosized vesicles because the exosomal molecules are protected from RNase/proteinase-dependent degradation, and can be stably detected in the circulating compartment, making them ideal biomarkers for several clinical applications (26).…”

mirRICH, a simple method to enrich the small RNA fraction from over-dried RNA pellets

“…Most commercial kits use SPE, which binds to small RNAs, and this method is considered the most suitable for isolating small RNAs [17]. However, column-based commercial miRNA extraction kits offer the advantage yielding high quantities of small RNAs, but the cost may be a burden [18]. Therefore, it is necessary to develop a superior yet low-cost method to enrich small RNAs.…”