title: Effect of culture at low oxygen tension on the expression of heat shock proteins in a panel of melanoma cell lines.
abstract: OBJECTIVE
  Tumours are commonly hypoxic and this can be associated with aggressive tumour type, metastasis and resistance to therapy. Heat shock proteins (hsps) are induced in response to hypoxia, provide cancer cells with protection against tumour-associated stressors and chaperone oncoproteins that drive tumour proliferation. This study examined the effect of different oxygen concentrations on the expression of hsps in melanoma cell lines.
  
  
  METHODS
  Melanoma cell lines were cultured in 2% and 20% O(2). Expression of Hsp90, Hsp70, Hsp60, Hsp40 and Hsp32 proteins were determined by flow cytometry.
  
  
  RESULTS
  Growth rates and viability were reduced in the majority of cell lines by culture in 2% O(2). Hsp expression was different in 2% compared to 20% O(2) and changes in Hsp90 expression correlated with cell line generation time (P<0.005) and viability (P<0.01). Greater total hsp expression correlated with improved viability in 2% but not 20% O(2) (P<0.05). Relative expression of the different hsps was consistent across cell lines and each correlated with the others (P = 0.0001) but not with Hsp32. Hsp expression was inversely correlated with cell line adhesion to laminin as well as collagen type IV and Breslow depth of the original primary tumour tissue (P<0.05), but not with Clark level or patient survival. All five hsps were identified on the cell surface.
  
  
  CONCLUSIONS
  Culture in 2% O(2) variably altered hsp expression in a panel of melanoma cell lines. Hsp expression was associated with certain cell line characteristics and clinical parameters of the originating tumour.
authors: Tübingen Ageing and Tumour Immunology Group, Department of Internal Medicine II, Centre for Medical Research, University of Tübingen, Tübingen, Baden-Württemberg, Germany. mrchristophershipp@gmail.com
authors: Christopher
authors: C
authors: Shipp
authors: Evelyna
authors: E
authors: Derhovanessian
authors: Graham
authors: G
authors: Pawelec
mesh_terms: D018929:Cell Culture Techniques; D049109:Cell Proliferation; D018834:Chaperonin 60 / Q000378:metabolism*; D005434:Flow Cytometry; D050956:HSP40 Heat-Shock Proteins / Q000378:metabolism*; D018840:HSP70 Heat-Shock Proteins / Q000378:metabolism*; D018841:HSP90 Heat-Shock Proteins / Q000378:metabolism*; D051547:Heme Oxygenase-1 / Q000378:metabolism*; D006801:Humans; D008545:Melanoma / Q000378:metabolism* / Q000401:mortality / Q000473:pathology; D010100:Oxygen / Q000494:pharmacology*; D015996:Survival Rate; D014407:Tumor Cells, Cultured
chemical_list: D018834:Chaperonin 60; C494647:DNAJB1 protein, human; D050956:HSP40 Heat-Shock Proteins; D018840:HSP70 Heat-Shock Proteins; D018841:HSP90 Heat-Shock Proteins; C496541:HMOX1 protein, human; D051547:Heme Oxygenase-1; D010100:Oxygen