title: Size Dependent Lipidomic Analysis of Urinary Exosomes from Patients with Prostate Cancer by Flow Field-Flow Fractionation and Nanoflow Liquid Chromatography-Tandem Mass Spectrometry.
abstract: Exosomes are membrane-bound extracellular vesicles involved in intercellular communication and tumor cell metastasis. In this study, flow field-flow fractionation (FlFFF) was utilized to separate urinary exosomes by size, demonstrating a significant difference in exosome sizes between healthy controls and patients with prostate cancer (PCa). Exosome fractions of different sizes were collected for microscopic analysis during an FlFFF run and evaluated with exosome marker proteins using Western blot analysis. The results indicated that exosomes of different sizes originated from different types of cells. Collected exosome fractions were further examined using nanoflow ultrahigh performance liquid chromatography-electrospray ionization-tandem mass spectrometry (nUPLC-ESI-MS/MS) for lipidomic analysis. A total of 162 lipids (from 286 identified) were quantified using a selected reaction monitoring (SRM) method. The overall amount of lipids increased by 1.5- to 2-fold in patients with PCa and degree of increase was more significant in the smaller fractions (diameter <150 nm) than in the larger ones (diameter >150 nm) some classes of lipids. In addition, neutral lipids like diacylglycerol (DAG) and triacylglycerol (TAG) decreased in all exosomes without size dependency. Moreover, a dramatic increase in 22:6/22:6-phosphatidylglycerol (PG) was observed and significant decrease in (16:0,16:0)- and (16:1, 18:1)-DAG species (nearly 5-fold) and high abundant TAG species (>2.5-fold) was observed in patients with PCa. The results of this study indicate that FlFFF can be employed for the high-speed screening of urinary exosome sizes in patients with PCa and lipidomic analysis of the fractionated exosomes has potential for developing and distinguishing biomarkers of PCa.
authors.affiliation: Department of Chemistry, Yonsei University , 50 Yonsei-Ro, Seoul, 03722 South Korea.
authors.forename: Joon Seon
authors.initials: JS
authors.lastname: Yang
authors.affiliation: Department of Chemistry, Yonsei University , 50 Yonsei-Ro, Seoul, 03722 South Korea.
authors.forename: Jong Cheol
authors.initials: JC
authors.lastname: Lee
authors.affiliation: Department of Chemistry, Yonsei University , 50 Yonsei-Ro, Seoul, 03722 South Korea.
authors.forename: Seul Kee
authors.initials: SK
authors.lastname: Byeon
authors.affiliation: Department of Urology, Yonsei University College of Medicine , 50-1 Yonsei-Ro, Seoul, 03722 South Korea.
authors.forename: Koon Ho
authors.initials: KH
authors.lastname: Rha
authors.affiliation: Department of Chemistry, Yonsei University , 50 Yonsei-Ro, Seoul, 03722 South Korea.
authors.forename: Myeong Hee
authors.identifier: 0000-0002-5454-2601
authors.initials: MH
authors.lastname: Moon
mesh_terms: D000328:Adult; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D004075:Diglycerides / Q000032:analysis; D055354:Exosomes / Q000378:metabolism*; D031521:Fractionation, Field Flow; D006801:Humans; D008055:Lipids / Q000032:analysis*; D008297:Male; D036103:Nanotechnology; D011471:Prostatic Neoplasms / Q000378:metabolism / Q000473:pathology*; D053719:Tandem Mass Spectrometry; D014280:Triglycerides / Q000032:analysis
chemical_list: D004075:Diglycerides; D008055:Lipids; D014280:Triglycerides