title: The odyssey of Hsp60 from tumor cells to other destinations includes plasma membrane-associated stages and Golgi and exosomal protein-trafficking modalities.
abstract: BACKGROUND
  In a previous work we showed for the first time that human tumor cells secrete Hsp60 via exosomes, which are considered immunologically active microvesicles involved in tumor progression. This finding raised questions concerning the route followed by Hsp60 to reach the exosomes, its location in them, and whether Hsp60 can be secreted also via other mechanisms, e.g., by the Golgi. We addressed these issues in the work presented here.
  
  
  RESULTS
  We found that Hsp60 localizes in the tumor cell plasma membrane, is associated with lipid rafts, and ends up in the exosomal membrane. We also found evidence that Hsp60 localizes in the Golgi apparatus and its secretion is prevented by an inhibitor of this organelle.
  
  
  CONCLUSIONS
  We propose a multistage process for the translocation of Hsp60 from the inside to the outside of the cell that includes a combination of protein traffic pathways and, ultimately, presence of the chaperonin in the circulating blood. The new information presented should help in designing future strategies for research and for developing diagnostic-monitoring means useful in clinical oncology.
authors: Dipartimento BIONEC, Sezione di Anatomia Umana, University of Palermo, Palermo, Italy.
authors: Claudia
authors: C
authors: Campanella
authors: Fabio
authors: F
authors: Bucchieri
authors: Anna M
authors: AM
authors: Merendino
authors: Alberto
authors: A
authors: Fucarino
authors: Giosalba
authors: G
authors: Burgio
authors: Davide F V
authors: DF
authors: Corona
authors: Giovanna
authors: G
authors: Barbieri
authors: Sabrina
authors: S
authors: David
authors: Felicia
authors: F
authors: Farina
authors: Giovanni
authors: G
authors: Zummo
authors: Everly Conway
authors: EC
authors: de Macario
authors: Alberto J L
authors: AJ
authors: Macario
authors: Francesco
authors: F
authors: Cappello
mesh_terms: D045744:Cell Line, Tumor; D018834:Chaperonin 60 / Q000378:metabolism*; D003600:Cytosol / Q000378:metabolism; D055354:Exosomes / Q000378:metabolism*; D005110:Extracellular Space / Q000378:metabolism; D006056:Golgi Apparatus / Q000378:metabolism*; D006801:Humans; D021962:Membrane Microdomains / Q000378:metabolism*; D021381:Protein Transport
chemical_list: D018834:Chaperonin 60