title: Screening of exosomal microRNAs from colorectal cancer cells.
abstract: BACKGROUND
  Cells release extracellular membrane vesicles including microvesicles known as exosomes. Exosomes contain microRNAs (miRNAs) however the full range within colorectal cancer cell secreted exosomes is unknown.
  
  
  OBJECTIVE
  To identify the full range of exosome encapsulated miRNAs secreted from 2 colorectal cancer cell lines and to investigate engineering of exosomes over-expressing miRNAs.
  
  
  METHODS
  Exosomes were isolated from HCT-116 and HT-29 cell lines. RNA was extracted from exosomes and microRNA array performed. Cells were engineered to express miR-379 (HCT-116-379) or a non-targeting control (HCT-116-NTC) and functional effects were determined. Exosomes secreted by engineered cells were transferred to recipient cells and the impact examined.
  
  
  RESULTS
  Microvesicles 40-100 nm in size secreted by cell lines were visualised and confirmed to express exosomal protein CD63. HT-29 exosomes contained 409 miRNAs, HCT-116 exosomes contained 393, and 338 were common to exosomes from both cell lines. Selected targets were validated. HCT-116-379 cells showed decreased proliferation (12-15% decrease, p < 0.001) and decreased migration (32-86% decrease, p < 0.001) compared to controls. HCT-116-379 exosomes were enriched for miR-379. Confocal microscopy visualised transfer of HCT-116-379 exosomes to recipient cells.
  
  
  CONCLUSIONS
  Colorectal cancer cells secrete a large number of miRNAs within exosomes. miR-379 decreases cell proliferation and migration, and miR-379 enriched exosomes can be engineered.
authors: Discipline of Surgery, Lambe Institute for Translational Research, National University of Ireland Galway, Galway, Ireland.
authors: Cillian
authors: C
authors: Clancy
authors: Discipline of Surgery, Lambe Institute for Translational Research, National University of Ireland Galway, Galway, Ireland.
authors: Sonja
authors: S
authors: Khan
authors: Discipline of Surgery, Lambe Institute for Translational Research, National University of Ireland Galway, Galway, Ireland.
authors: Claire L
authors: CL
authors: Glynn
authors: School of Mathematics, Statistics and Applied Mathematics, National University of Ireland Galway, Galway, Ireland.
authors: Emma
authors: E
authors: Holian
authors: Discipline of Anatomy, National University of Ireland Galway, Galway, Ireland.
authors: Peter
authors: P
authors: Dockery
authors: Discipline of Anatomy, National University of Ireland Galway, Galway, Ireland.
authors: Pierce
authors: P
authors: Lalor
authors: Discipline of Surgery, Lambe Institute for Translational Research, National University of Ireland Galway, Galway, Ireland.
authors: James A L
authors: JA
authors: Brown
authors: Discipline of Surgery, Lambe Institute for Translational Research, National University of Ireland Galway, Galway, Ireland.|Department of Colorectal Surgery, Galway University Hospital, Galway, Ireland.
authors: Myles R
authors: MR
authors: Joyce
authors: Discipline of Surgery, Lambe Institute for Translational Research, National University of Ireland Galway, Galway, Ireland.
authors: Michael J
authors: MJ
authors: Kerin
authors: Discipline of Surgery, Lambe Institute for Translational Research, National University of Ireland Galway, Galway, Ireland.
authors: Roisin M
authors: RM
authors: Dwyer
mesh_terms: D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000235:genetics; D015179:Colorectal Neoplasms / Q000235:genetics* / Q000473:pathology; D055354:Exosomes / Q000235:genetics*; D045325:HCT116 Cells; D019073:HT29 Cells; D006801:Humans; D035683:MicroRNAs / Q000235:genetics*
chemical_list: D035683:MicroRNAs
keywords: Exosomes; colorectal cancer; microRNAs