title: Induction of anoikis by sodium arsenite in rat hepatoma FGC4 cells: comparison with cadmium chloride and implications for assessment of regulation of heat shock protein 70.
abstract: BACKGROUND
  Arsenic, a toxic metalloid with major health concerns, elicits upregulation of heat shock protein 70 (HSP70) in rat hepatoma FGC4 cells, together with evidence of detachment of viable cells from the growth substratum.
  
  
  OBJECTIVE
  To determine if this cell detachment was linked to anoikis, and the impact of this on measurement of HSP70 expression.
  
  
  METHODS
  FGC4 cells were exposed to sodium arsenite, and detached and attached cells were taken for assessment of cell viability, activation of procaspase-3, and expression of HSP70.
  
  
  RESULTS
  Exposure to sodium arsenite led to loss of viable cells from the substratum, associated with apoptosis in detached, but not attached, cells. Upregulation of HSP70 of a similar magnitude was demonstrated in both cell populations. Exposure of cells to cadmium chloride, a toxic metal, also of major environmental concern and believed to act by an oxidative stress mechanism, produced very little release of viable cells from the culture substratum, was not associated with apoptosis, but did elicit a modest upregulation of HSP70 in both cell populations.
  
  
  CONCLUSIONS
  Exposure of FGC4 cells to sodium arsenite elicits anoikis, a form of anchorage-dependent apoptosis, and assessment of the level of HSP70 upregulation in such cells should take account of the detached cell population. Further, the data suggest that this phenomenon is selective to sodium arsenite, rather than to another toxic element that shares a similar mechanism of toxicity.
authors: School of Biomedical Sciences, University of Nottingham Medical School, Queen's Medical Centre, Nottingham, UK.
authors: Mudafara
authors: M
authors: Bengleil
authors: Sherifa
authors: S
authors: Hassaneen
authors: Jeffrey R
authors: JR
authors: Fry
mesh_terms: D000818:Animals; D023102:Anoikis / Q000187:drug effects*; D017209:Apoptosis / Q000187:drug effects; D018053:Arsenites / Q000633:toxicity*; D015153:Blotting, Western; D019256:Cadmium Chloride / Q000633:toxicity*; D006528:Carcinoma, Hepatocellular / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D053148:Caspase 3 / Q000378:metabolism; D002448:Cell Adhesion / Q000187:drug effects; D045744:Cell Line, Tumor; D002470:Cell Survival / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D004785:Environmental Pollutants / Q000633:toxicity*; D018840:HSP70 Heat-Shock Proteins / Q000096:biosynthesis*; D022781:Hepatocytes / Q000187:drug effects / Q000378:metabolism / Q000473:pathology; D008113:Liver Neoplasms / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D051381:Rats; D017670:Sodium Compounds / Q000633:toxicity*; D015854:Up-Regulation / Q000187:drug effects
chemical_list: D018053:Arsenites; D004785:Environmental Pollutants; D018840:HSP70 Heat-Shock Proteins; D017670:Sodium Compounds; C017947:sodium arsenite; D053148:Caspase 3; D019256:Cadmium Chloride