Detection of circulating miRNAs : comparative analysis of extracellular vesicle-incorporated miRNAs and cell-free miRNAs in whole plasma of prostate cancer patients

Funding Information: This study was supported by the Norwegian Financial Mechanism 2009–2014 under Project Contract No NFI/R/2014/045. The funding body had no role in the design of the study and collection, analysis, and interpretation of data and in writing the manuscript. Publisher Copyright: © 2017 The Author(s).Background: Circulating cell-free miRNAs have emerged as promising minimally-invasive biomarkers for early detection, prognosis and monitoring of cancer. They can exist in the bloodstream incorporated into extracellular vesicles (EVs) and ribonucleoprotein complexes. However, it is still debated if EVs contain biologically meaningful amounts of miRNAs and may provide a better source of miRNA biomarkers than whole plasma. The aim of this study was to systematically compare the diagnostic potential of prostate cancer-associated miRNAs in whole plasma and in plasma EVs. Methods: RNA was isolated from whole plasma and plasma EV samples from a well characterised cohort of 50 patient with prostate cancer (PC) and 22 patients with benign prostatic hyperplasia (BPH). Nine miRNAs known to have a diagnostic potential for PC in cell-free blood were quantified by RT-qPCR and the relative quantities were compared between patients with PC and BPH and between PC patients with Gleason score ≥ 8 and ≤6. Results: Only a small fraction of the total cell-free miRNA was recovered from the plasma EVs, however the EV-incorporated and whole plasma cell-free miRNA profiles were clearly different. Four of the miRNAs analysed showed a diagnostic potential in our patient cohort. MiR-375 could differentiate between PC and BPH patients when analysed in the whole plasma, while miR-200c-3p and miR-21-5p performed better when analysed in plasma EVs. EV-incorporated but not whole plasma Let-7a-5p level could distinguish PC patients with Gleason score ≥ 8 vs ≤6. Conclusions: This study demonstrates that for some miRNA biomarkers EVs provide a more consistent source of RNA than whole plasma, while other miRNAs show better diagnostic performance when tested in the whole plasma.publishersversionPeer reviewe

Circulating miRNAs as biomarkers in multiple sclerosis

Vairākos pētījumos ir atklātas miRNS, tajā skaitā cirkulējošas miRNS, kuru daudzums ir izmainīts multiplā sklerozē. miRNS kā jaunu biomarķieru izpēte šai slimībai varētu palīdzēt diagnosticēt un prognozēt tās attīstību agrīnā stadijā. Šajā pētījumā ir prezentēti mūsu dati par dažām miRNS, kas tikadetektētas MS pacientu asins plazmā, kā izmainītas. Mēs salīdzinājām miRNS ekspresijas līmeņus MS un tās apakštipos ar veselo kontroli, lai atrastu potenciālās miRNS, kas var tikt izmantotas, kā MS biomarķieri. Galvenais mērķis bija validēt sekvenēšanas rezultātā atlasītās miRNS, kuru daudzums bija izmainīts MS pacientu asins plazmā neatkarīgā pacientu kopā. miRNS 484, kuras daudzums bija visvairāk izmainīts saskaņā ar sekvenēšanas datiem, tika validēta ar qPCR neatkarīgā MS pacientu kopā. Tas norāda uz šīs miRNS potenciālu kā MS diagnostiskais biomarķieris.Several studies found miRNAs to be dysregulated in multiple sclerosis including circulating cell-free miRNAs. Investigation of miRNAs as novel biomarkers could help to diagnose and predict the development of the disease in early stages. Here, we present our data of several miRNAs found in blood plasma of MS patients. We compared expression levels of miRNAs in MS and its subtypes versus healthy controls in order to find a link between miRNA dysregulation and the disease. The main aim was to validate the dysregulation of selected circulating miRNAs in MS patients, indicated by our sequencing results of a discovery group, in an independent validation group. miRNA-484, which was the most significantly dysregulated miRNA according to the sequencing experiment, could be validated by qPCR in MS patients. This indicates the potential of miRNA-484 to serve as diagnostic MS biomarker

Discovery of extracellular vesicle-enclosed microbial RNA in human blood and urine

Gandrīz visi cilvēka šūnu tipi sekretē ekstracelulārās vezikulas (EVs), un tām ir svarīga loma starpšūnu komunikācijā. Jaunākie pētījumi liecina, ka komunikācija notiek arī starp cilvēka mikrobiotu un saimniekorganisma šūnām. Šajā pētījumā mēs parādām, ka no cilvēka asinīm un urīna izdalītās EVs satur RNS fragmentus no dažādiem mikroorganismiem. Visbiežāk sastopami baktēriju tipi un supertipi asinīs un urīnā bija Proteobacteria, PVC grupa un Terrabacteria. Lai noteiktu vai šo mikrobiālo transkriptu galvenais avots ir zarnu mikrobioms, mēs izstrādājām EV izdalīšanas metodi no cilvēku fēču paraugiem. Tālāk mēs plānojām veikt RNS sekvencēšanas (RNA-seq) analīzi EV, kas izdalītas no plazmas, urīna un fēcēm no tiem pašiem indivīdiem.According to numerous studies, extracellular vesicles (EVs) are released by almost all cell types within human body and act as mediators of various biological processes via cell-to-cell communication. Recent studies show that intercellular communication is possible between human microbiota and host cells as well. In this study, we show that EVs isolated from human blood and urine contain RNA fragments derived from various microorganisms. The most commonly represented phyla and superphyla in blood and urine were Proteobacteria, PVC group and Terrabacteria. To determine if the major source of these microbial transcripts is gut microbiome, we developed a method for the isolation of EVs from human stool samples. Next, we plan to perform RNA sequencing (RNA-seq) analysis of EVs isolated from plasma, urine and stool from the same individuals