Abstract PR15: Charting extracellular transcriptomes in The Human Biofluid RNA Atlas
Authors: Hulstaert Eva , Morlion Annelien , Cobos Francisco Avila , Verniers Kimberly , Nuytens Justine , Eynde Eveline Vanden , Yigit Nurten , Anckaert Jasper , Geerts Anja , Hindryckx Pieter , Jacques Peggy , Brusselle Guy , Bracke Ken , Maes Tania , Malfait Thomas , Derveaux Thierry , Ninclaus Virginie , Van Cauwenbergh Caroline , Roelens Kristien , Roets Ellen , Hemelsoet Dimitri , Tilleman Kelly , Brochez Lieve , Kuersten Scott , Simon Lukas , Karg Sebastian , Nöhammer Christa , Kautzky-Willers Alexandra , Leutner Michael , Slaby Ondrej , Schroth Gary , Vandesompele Jo , Mestdagh Pieter 
Published: June 2020

Abstract
Liquid biopsies offer a minimally invasive alternative to tissue biopsies for both diagnosis and monitoring of treatment response. Extracellular RNAs present in biofluids have emerged as potential biomarkers in health and disease, including cancer. While current studies typically focus on plasma or serum, other biofluids may contain more informative RNA molecules for particular disease types. Here, we present an unprecedented atlas of messenger, circular, and small RNA transcriptomes of a comprehensive collection of 20 different human biofluids (amniotic fluid, aqueous humor, ascites, bile, bronchial lavage fluid, breast milk, cerebrospinal fluid, colostrum, gastric fluid, pancreatic cyst fluid, plasma, saliva, seminal fluid, serum, sputum, stool, synovial fluid, sweat, tear fluid, and urine). By means of 173 synthetic RNA spike-in controls, we compared RNA content across biofluids, revealing a more than 10,000-fold difference in RNA concentration. Of interest, the circular RNA fraction is significantly increased in nearly all biofluids compared to various solid tissues. Each biofluid transcriptome is enriched for RNA molecules derived from specific tissues and cell types. In addition, a subset of biofluids, including stool, sweat, saliva, and sputum, contain high levels of bacterial RNAs. These findings enable a more informed selection of the most relevant biofluid to monitor individual cancer types. To verify the biomarker potential in these biofluids, four validation cohorts representing a broad spectrum of diseases, including urine from bladder cancer patients and CSF from glioblastoma patients, were profiled, revealing differential RNAs between case and control subjects. Taken together, our results reveal novel insights in the RNA content of human biofluids and may serve as a valuable resource for future biomarker studies.
This abstract is also being presented as Poster B01.
Citation Format: Eva Hulstaert, Annelien Morlion, Francisco Avila Cobos, Kimberly Verniers, Justine Nuytens, Eveline Vanden Eynde, Nurten Yigit, Jasper Anckaert, Anja Geerts, Pieter Hindryckx, Peggy Jacques, Guy Brusselle, Ken Bracke, Tania Maes, Thomas Malfait, Thierry Derveaux, Virginie Ninclaus, Caroline Van Cauwenbergh, Kristien Roelens, Ellen Roets, Dimitri Hemelsoet, Kelly Tilleman, Lieve Brochez, Scott Kuersten, Lukas Simon, Sebastian Karg, Christa Nöhammer, Alexandra Kautzky-Willers, Michael Leutner, Ondrej Slaby, Gary Schroth, Jo Vandesompele, Pieter Mestdagh. Charting extracellular transcriptomes in The Human Biofluid RNA Atlas [abstract]. In: Proceedings of the AACR Special Conference on Advances in Liquid Biopsies; Jan 13-16, 2020; Miami, FL. Philadelphia (PA): AACR; Clin Cancer Res 2020;26(11_Suppl):Abstract nr PR15.