BACKGROUND: Hsp60, a Group I mitochondrial chaperonin, is classically considered an intracellular chaperone with residence in the mitochondria; nonetheless, in the last few years it has been found extracellularly as well as in the cell membrane. Important questions remain pertaining to extracellular Hsp60 such as how generalized is its occurrence outside cells, what are its extracellular functions and the translocation mechanisms that transport the chaperone outside of the cell. These questions are particularly relevant for cancer biology since it is believed that extracellular chaperones, like Hsp70, may play an active role in tumor growth and dissemination. METHODOLOGY/PRINCIPAL FINDINGS: Since cancer cells may undergo necrosis and apoptosis, it could be possible that extracellular Hsps are chiefly the result of cell destruction but not the product of an active, physiological process. In this work, we studied three tumor cells lines and found that they all release Hsp60 into the culture media by an active mechanism independently of cell death. Biochemical analyses of one of the cell lines revealed that Hsp60 secretion was significantly reduced, by inhibitors of exosomes and lipid rafts. CONCLUSIONS/SIGNIFICANCE: Our data suggest that Hsp60 release is the result of an active secretion mechanism and, since extracellular release of the chaperone was demonstrated in all tumor cell lines investigated, our observations most likely reflect a general physiological phenomenon, occurring in many tumors.

Merendino, A.M., Bucchieri, F., Campanella, C., Marcianò, V., Ribbene, A., David, S., et al. (2010). Hsp60 is actively secreted by human tumor cells. PLOS ONE, 5(2).

Hsp60 is actively secreted by human tumor cells

MERENDINO, Anna Maria;BUCCHIERI, Fabio;CAMPANELLA, Claudia;MARCIANO', Vito;RIBBENE, Anna;DAVID, Sabrina;ZUMMO, Giovanni;BURGIO, Giosalba;CORONA, Davide;CAPPELLO, Francesco
2010-01-01

Abstract

BACKGROUND: Hsp60, a Group I mitochondrial chaperonin, is classically considered an intracellular chaperone with residence in the mitochondria; nonetheless, in the last few years it has been found extracellularly as well as in the cell membrane. Important questions remain pertaining to extracellular Hsp60 such as how generalized is its occurrence outside cells, what are its extracellular functions and the translocation mechanisms that transport the chaperone outside of the cell. These questions are particularly relevant for cancer biology since it is believed that extracellular chaperones, like Hsp70, may play an active role in tumor growth and dissemination. METHODOLOGY/PRINCIPAL FINDINGS: Since cancer cells may undergo necrosis and apoptosis, it could be possible that extracellular Hsps are chiefly the result of cell destruction but not the product of an active, physiological process. In this work, we studied three tumor cells lines and found that they all release Hsp60 into the culture media by an active mechanism independently of cell death. Biochemical analyses of one of the cell lines revealed that Hsp60 secretion was significantly reduced, by inhibitors of exosomes and lipid rafts. CONCLUSIONS/SIGNIFICANCE: Our data suggest that Hsp60 release is the result of an active secretion mechanism and, since extracellular release of the chaperone was demonstrated in all tumor cell lines investigated, our observations most likely reflect a general physiological phenomenon, occurring in many tumors.
2010
Merendino, A.M., Bucchieri, F., Campanella, C., Marcianò, V., Ribbene, A., David, S., et al. (2010). Hsp60 is actively secreted by human tumor cells. PLOS ONE, 5(2).
File in questo prodotto:
File Dimensione Formato  
10447-54468.pdf

accesso aperto

Dimensione 239.66 kB
Formato Adobe PDF
239.66 kB Adobe PDF Visualizza/Apri

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/10447/54468
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 142
  • ???jsp.display-item.citation.isi??? 136
social impact