title: Extracellular vesicle-mediated phenotype switching in malignant and non-malignant colon cells.
abstract: BACKGROUND
  Extracellular vesicles (EVs) are secreted from many cells, carrying cargoes including proteins and nucleic acids. Research has shown that EVs play a role in a variety of biological processes including immunity, bone formation and recently they have been implicated in promotion of a metastatic phenotype.
  
  
  METHODS
  EVs were isolated from HCT116 colon cancer cells, 1459 non-malignant colon fibroblast cells, and tumor and normal colon tissue from a patient sample. Co-cultures were performed with 1459 cells and malignant vesicles, as well as HCT116 cells and non-malignant vesicles. Malignant phenotype was measured using soft agar colony formation assay. Co-cultures were also analyzed for protein levels using mass spectrometry. The importance of 14-3-3 zeta/delta in transfer of malignant phenotype was explored using siRNA. Additionally, luciferase reporter assay was used to measure the transcriptional activity of NF-κB.
  
  
  RESULTS
  This study demonstrates the ability of EVs derived from malignant colon cancer cell line and malignant patient tissue to induce the malignant phenotype in non-malignant colon cells. Similarly, EVs derived from non-malignant colon cell lines and normal patient tissue reversed the malignant phenotype of HCT116 cells. Cells expressing an EV-induced malignant phenotype showed increased transcriptional activity of NF-κB which was inhibited by the NF--κB inhibitor, BAY117082. We also demonstrate that knock down of 14-3-3 zeta/delta reduced anchorage-independent growth of HCT116 cells and 1459 cells co-cultured with HCT derived EVs.
  
  
  CONCLUSIONS
  Evidence of EV-mediated induction of malignant phenotype, and reversal of malignant phenotype, provides rational basis for further study of the role of EVs in tumorigenesis. Identification of 14-3-3 zeta/delta as up-regulated in malignancy suggests its potential as a putative drug target for the treatment of colorectal cancer.
authors.affiliation: Department of Medicine, Rhode Island Hospital and The Alpert Medical School of Brown University, Coro West, Suite 5.01, One Hoppin St, Providence, RI, 02903, USA. hillary.e.mulvey@gmail.com.
authors.forename: Hillary E
authors.initials: HE
authors.lastname: Mulvey
authors.affiliation: Department of Medicine, Rhode Island Hospital and The Alpert Medical School of Brown University, Coro West, Suite 5.01, One Hoppin St, Providence, RI, 02903, USA. audreyyychang@gmail.com.
authors.forename: Audrey
authors.initials: A
authors.lastname: Chang
authors.affiliation: Department of Medicine, Rhode Island Hospital and The Alpert Medical School of Brown University, Coro West, Suite 5.01, One Hoppin St, Providence, RI, 02903, USA. jaadler23@gmail.com.
authors.forename: Jason
authors.initials: J
authors.lastname: Adler
authors.affiliation: Department of Medicine, Rhode Island Hospital and The Alpert Medical School of Brown University, Coro West, Suite 5.01, One Hoppin St, Providence, RI, 02903, USA. mdeltatto1@lifespan.org.
authors.forename: Michael
authors.initials: M
authors.lastname: Del Tatto
authors.affiliation: Department of Medicine, Rhode Island Hospital and The Alpert Medical School of Brown University, Coro West, Suite 5.01, One Hoppin St, Providence, RI, 02903, USA. kperez@lifespan.org.
authors.forename: Kimberly
authors.initials: K
authors.lastname: Perez
authors.affiliation: Department of Medicine, Rhode Island Hospital and The Alpert Medical School of Brown University, Coro West, Suite 5.01, One Hoppin St, Providence, RI, 02903, USA. pquesenberry@lifespan.org.
authors.forename: Peter J
authors.initials: PJ
authors.lastname: Quesenberry
authors.affiliation: Department of Medicine, Rhode Island Hospital and The Alpert Medical School of Brown University, Coro West, Suite 5.01, One Hoppin St, Providence, RI, 02903, USA. Devasis_chatterjee@brown.edu.
authors.forename: Devasis
authors.initials: D
authors.lastname: Chatterjee
mesh_terms: D048948:14-3-3 Proteins / Q000378:metabolism*; D045744:Cell Line, Tumor; D018920:Coculture Techniques; D003106:Colon / Q000166:cytology / Q000378:metabolism*; D003110:Colonic Neoplasms / Q000378:metabolism / Q000473:pathology*; D000067128:Extracellular Vesicles / Q000378:metabolism*; D005347:Fibroblasts / Q000378:metabolism*; D015972:Gene Expression Regulation, Neoplastic; D045325:HCT116 Cells; D006801:Humans; D010641:Phenotype; D015854:Up-Regulation
chemical_list: D048948:14-3-3 Proteins; C572235:YWHAZ protein, human