title: Exosomal shuttling of miR-126 in endothelial cells modulates adhesive and migratory abilities of chronic myelogenous leukemia cells.
abstract: BACKGROUND
  Recent findings indicate that exosomes released from cancer cells contain microRNAs (miRNAs) that may be delivered to cells of tumor microenvironment.
  
  
  RESULTS
  To elucidate whether miRNAs secreted from chronic myelogenous leukemia cells (CML) are shuttled into endothelial cells thus affecting their phenotype, we first analysed miRNAs content in LAMA84 exosomes. Among the 124 miRNAs identified in LAMA84 exosomes, we focused our attention on miR-126 which was found to be over-overexpressed in exosomes compared with producing parental cells. Transfection of LAMA84 with Cy3-labelled miR-126 and co-culture of leukemia cells with endothelial cells (EC) confirmed that miR-126 is shuttled into HUVECs. The treatment of HUVECs with LAMA84 exosomes for 24 hours reduced CXCL12 and VCAM1 expression, both at the mRNA and protein level, and negatively modulated LAMA84 motility and cells adhesion. Transfection in HUVECs of miR-126 inhibitor reversed the decrease of CXCL12 and restored the motility and adhesion of LAMA84 cells while the over-expression of miR-126, showed opposite effects.
  
  
  CONCLUSIONS
  Our results show that the miR-126 shuttled by exosomes is biologically active in the target cells, and support the hypothesis that exosomal miRNAs have an important role in tumor-endothelial crosstalk occurring in the bone marrow microenvironment, potentially affecting disease progression.
authors.forename: Simona
authors.initials: S
authors.lastname: Taverna
authors.forename: Valeria
authors.initials: V
authors.lastname: Amodeo
authors.forename: Laura
authors.initials: L
authors.lastname: Saieva
authors.forename: Antonio
authors.initials: A
authors.lastname: Russo
authors.forename: Marco
authors.initials: M
authors.lastname: Giallombardo
authors.forename: Giacomo
authors.initials: G
authors.lastname: De Leo
authors.affiliation: Dipartimento di Biopatologia e Metodologie Biomediche, Sezione di Biologia e Genetica, Università di Palermo, Palermo, Italy. riccardo.alessandro@unipa.it.
authors.forename: Riccardo
authors.initials: R
authors.lastname: Alessandro
mesh_terms: D002448:Cell Adhesion / Q000235:genetics; D045744:Cell Line, Tumor; D002465:Cell Movement / Q000235:genetics; D054377:Chemokine CXCL12 / Q000096:biosynthesis; D042783:Endothelial Cells / Q000378:metabolism; D055354:Exosomes / Q000235:genetics / Q000378:metabolism*; D061307:Human Umbilical Vein Endothelial Cells; D006801:Humans; D015464:Leukemia, Myelogenous, Chronic, BCR-ABL Positive / Q000235:genetics* / Q000378:metabolism* / Q000473:pathology; D035683:MicroRNAs / Q000235:genetics*; D019010:Vascular Cell Adhesion Molecule-1 / Q000096:biosynthesis
chemical_list: C515255:CXCL12 protein, human; D054377:Chemokine CXCL12; C527111:MIRN126 microRNA, human; D035683:MicroRNAs; D019010:Vascular Cell Adhesion Molecule-1