Conley, AndrewMinciacchi, Valentina R.Lee, Dhong HyunKnudsen, Beatrice S.Karlan, Beth Y.Citrigno, LuigiViglietto, GiuseppeTewari, MuneeshFreeman, Michael R.Demichelis, FrancescaDi Vizio, Dolores2017-05-012017Conley, A., V. R. Minciacchi, D. H. Lee, B. S. Knudsen, B. Y. Karlan, L. Citrigno, G. Viglietto, et al. 2017. “High-throughput sequencing of two populations of extracellular vesicles provides an mRNA signature that can be detected in the circulation of breast cancer patients.” RNA Biology 14 (3): 305-316. doi:10.1080/15476286.2016.1259061. http://dx.doi.org/10.1080/15476286.2016.1259061.http://nrs.harvard.edu/urn-3:HUL.InstRepos:32630490ABSTRACT Extracellular vesicles (EVs) contain a wide range of RNA types with a reported prevalence of non-coding RNA. To date a comprehensive characterization of the protein coding transcripts in EVs is still lacking. We performed RNA-Sequencing (RNA-Seq) of 2 EV populations and identified a small fraction of transcripts that were expressed at significantly different levels in large oncosomes and exosomes, suggesting they may mediate specialized functions. However, these 2 EV populations exhibited a common mRNA signature that, in comparison to their donor cells, was significantly enriched in mRNAs encoding E2F transcriptional targets and histone proteins. These mRNAs are primarily expressed in the S-phase of the cell cycle, suggesting that they may be packaged into EVs during S-phase. In silico analysis using subcellular compartment transcriptome data from the ENCODE cell line compendium revealed that EV mRNAs originate from a cytoplasmic RNA pool. The EV signature was independently identified in plasma of patients with breast cancer by RNA-Seq. Furthermore, several transcripts differentially expressed in EVs from patients versus controls mirrored differential expression between normal and breast cancer tissues. Altogether, this largest high-throughput profiling of EV mRNA demonstrates that EVs carry tumor-specific alterations and can be interrogated as a source of cancer-derived cargo.en-USJournal Article2017-05-0110.1080/15476286.2016.1259061