Ods: Omental fat exosomes have been created from fresh human omental fat specimens. Proliferation, migration, invasion and chemoresistance had been utilized to evaluate the phenotypic behaviour of omental-exosomes treated gastric cancer cells. Applying a extensive cytokine array, we identified the proteome of omental-exosomes. Exosomal miRNAs have been profiled working with NanoString technologies. A xenograft model wasJOURNAL OF EXTRACELLULAR VESICLES Universidade da Coru . Xubias de Arriba, 84 15006 A Coru , Spain., A Coru , SpainIntroduction: Connexin43 (Cx43), a transmembrane protein involved in cell communication and signalling, has been described as a tumour suppressor element in melanoma, on the other hand its part in disease progression remains below debate. Extracellular vesicles (EVs) released by melanoma cells give signals and “educate” distant cells. The presence of Cx43 in EVs delivers these particles with an added capacity to exchange smaller molecules for example RNAs, metabolites or ions with target cells via gap junction channels (GJs).B7-H3/CD276 Proteins medchemexpress Within this study, we have investigated the role of exosomal Cx43 in metastatic melanoma. Solutions: Protein levels and activity had been studied by western-blot, immunofluorescence, colony formation and proliferation and migration assays. GJIC by Scrape loading. EVs were isolated by ultracentrifugation and analysed applying the NanoSight and electron microscopy. Their content material was analysed by mass spectrometry (MS) and by RNA-seq. Benefits: Low levels and SUMOylated Cx43 in BRAFmutant human melanoma cells was CD131 Proteins medchemexpress associated with cytoplasmic distribution and low incidence of dye coupling (GJIC). Ectopic Cx43 gene expression usingvectors restored Cx43 membrane localization, raised GJIC and enhanced Cx43 inside the EVs. EVs isolated from BRAF-mutant melanoma cells overexpressing Cx43 only consists of the non-SUMOylated Cx43. When diverse melanoma cell lines were exposed to exosomes containing Cx43, these EVs considerably decreased cell proliferation and blocked colonies development. The effect of exosomal Cx43 was in comparison to the overexpression of the protein. The presence of Cx43 in EVs considerably enhanced the sensitivity of BRAF-mutant metastatic melanoma to drugs such as BRAF/MEK inhibitors. The RNA and proteomic element identified by RNA-Seq and MS revealed that exosomal Cx43 by way of its scaffolding function may be involved in the recruitment of proteins and compact RNAs towards the EVs switching the messages and therefore the role of these EVs in melanoma. Summary/Conclusion: Our outcomes indicate that exosomal particles containing Cx43 are potent autos to combat metastatic melanoma. Additional understanding of your role of Cx43 in EVs will have implications for the improvement of new therapeutic tactics. As an example, we demonstrated their ability as drug carriers to combat metastasic melanoma when these vesicles contain Cx43.ISEV2019 ABSTRACT BOOKSymposium Session 4: EV Biogenesis I Chairs: Nobuyoshi Kosaka; Clotilde Th y Location: Level B1, Hall A 11:002:OT04.Linking the trafficking of CD63 and CD9 to their secretion mechanisms into extracellular vesicles Mathilde Mathieua, JosIgnacio Valenzuelab, Mathieu Maurina, Mabel Jouvea, Nathalie Nevoa, Ga le Boncompaina, Franck Perezb and Clotilde Theryca Institut Curie, INSERM U932, Paris, France; bInstitut Curie, umr144, Paris, France; 3Institue Curie, Paris, Franceobserved improved secretion of CD63+ but not CD9 + EVs. Summary/Conclusion: Our benefits demonstrate that modest EVs can form both at t.