Ns, also as autophagy-related proteins which includes LC3 and p62, within the EV fraction in the culture media. We also identified that inhibitor treatment facilitates secretion of EVs distinct from exosomes in size, and that these EVs are involved in secretion of ubiquitinated proteins. Interestingly, analysis of knockout cells deficient for autophagy-related proteins revealed that the elements inside the initiation step of autophagy are needed for EVmediated secretion of ubiquitinated proteins.ISEV2019 ABSTRACT BOOKSummary/Conclusion: These Membrane Cofactor Protein/CD46 Proteins custom synthesis Results indicate that autophagy impairment promotes secretion of ubiquitinated proteins by way of EVs. Our data give the mechanistic link involving the autophagy/lysosome pathway and vesicle secretion. We propose that cells may use the EV-mediated secretion as an option pathway to preserve protein homeostasis when cellular proteostasis machinery is functionally impaired. Funding: This function was supported by JST; by KAKENHI (18H02585); by The Asahi Grass Foundation plus the Tokyo Biochemical Study Foundation.miRNAs, four miRNAs altered the EV secretion in each cell lines, HCT116 and A549. Summary/Conclusion: A few of these target genes have reported as endosomal pathway related protein and shown the up-regulation in cancer cells. These findings recommend that the identification of target genes of these miRNAs provides the new insight in to the cancer cell communication with all the microenvironmental cells, which results in a promising therapeutic method against cancer progression.PF07.04 PF07.Identifying the miRNAs linked with EV Secretion from cancer cell lines Tomofumi Yamamotoa, Nobuyoshi Kosakab, Fumihiko Urabea, Yutaka Hattoric and Takahiro Ochiyab Division of Molecular and Cellular Medicine, National Cancer Center Analysis Institute, Tokyo, Japan; bDepartment of Molecular and Cellular Medicine, Institute of Health-related Science, Tokyo Medical University, Shinjyuku-ku, Japan; cClinical Physiology and Therapeutics, Keio University Faculty of Pharmacy, Tokyo, JapanaRas Tumour microvesicles biogenesis and signalling in drosophila Vakil Ahmad, Carson Broeker, Kayla Calandro and Yves Chiswili. Chabu University of Missouri, Columbia, USAIntroduction: Extracellular vesicles (EVs) derived from cancer cells contribute to their surrounding microenvironmental cells for their advantage. Our group has previously shown that inhibiting the EVs production attenuated the angiogenesis in the tumour, resulting within the suppression of metastasis. Therefore, understanding the mechanisms of EV secretion could contribute towards the regulation of EVmediated cancer progression. Having said that, the VISTA Proteins Biological Activity precise mechanism of EV secretion in cancer cells remains unclear. The objective of this study will be to elucidate the unknown mechanisms of EV secretion in cancer cells. To reveal this, microRNAs (miRNAs), which regulate various genes, are employed. Procedures: To identify the EV secretion related miRNAs, miRNA-based screening strategy was established. Combined with ExoScreen, which can be ultra-sensitive detection system of EV by measuring surface protein of EVs, such as CD9 and CD63, miRNAbased screening was performed in colorectal cancer cell line, HCT116, and lung cancer cell line, A549. The results in the screening have been confirmed by the nanoparticle tracking evaluation. Candidate genes of those miRNAs have been chosen by in silico analysis. Results: In the initial 1728 miRNAs, we identified 13 miRNAs that are connected with EV secretion in each and every cell lines. Then, the target.
