Relationships between thermotolerance, oxidative stress responses and induction of stress proteins in human tumour cell lines.
Thermotolerance, resistance to oxidative stress and induction of stress proteins were examined in a panel of 10 human tumour cell lines. An inverse relationship was indicated between intrinsic thermotolerance (cell survival after treatment at 43.5 degrees for 3 hr) and thermotolerance induced by pretreatment at 42.5 degrees for 30 min. Similar levels of induction of hsp 70 were found in cell lines with high or low levels of intrinsic thermotolerance; induction of other stress proteins could not be detected. Cell survival following treatment with H2O2 correlated with that following streptonigrin treatment (P < 0.05). Pretreatment with buthionine sulphoximine or diamide synergistically increased the toxicity of heat, H2O2 and streptonigrin whereas reduced glutathione had the reverse effect. No direct correlation was found, however, between tolerance to heat and to oxidative stress, and hsp 70 was not induced by the latter. The stress protein heme oxygenase, detected by immunoblotting with the monoclonal antibody HO, was induced by H2O2 in melanoma cell lines but not in HeLa. Cadmium and arsenite ions, however, readily induced heme oxygenase in HeLa, indicating that in these cells induction of heme oxygenase by oxidative stress involves a different mechanism. Overall, the results suggest that tolerance to heat or oxidative stress in these cell lines may not necessarily be associated with the induction of heat shock proteins or heme oxygenase but that cell survival after both types of stress depends to a certain extent on cellular sulphydryls.
Steels
E L
EL
Department of Biochemistry, Microbiology and Nutrition, University of New England, Armidale, New South Wales, Australia.
Watson
K
K
Parsons
P G
PG
D000222:Adaptation, Physiological / Q000502:physiology*; D002470:Cell Survival / Q000502:physiology; D006367:HeLa Cells; D006360:Heat-Shock Proteins / Q000096:biosynthesis*; D006419:Heme Oxygenase (Decyclizing) / Q000096:biosynthesis; D006358:Hot Temperature; D006801:Humans; D006861:Hydrogen Peroxide / Q000633:toxicity; D008545:Melanoma / Q000201:enzymology / Q000378:metabolism / Q000503:physiopathology; D009374:Neoplasms, Experimental / Q000201:enzymology / Q000378:metabolism* / Q000503:physiopathology; D010084:Oxidation-Reduction; D010100:Oxygen / Q000378:metabolism / Q000633:toxicity*; D017382:Reactive Oxygen Species / Q000633:toxicity; D013308:Streptonigrin / Q000633:toxicity; D013312:Stress, Physiological / Q000139:chemically induced / Q000209:etiology / Q000378:metabolism*; D013439:Sulfhydryl Reagents / Q000494:pharmacology; D014407:Tumor Cells, Cultured
D006360:Heat-Shock Proteins; D017382:Reactive Oxygen Species; D013439:Sulfhydryl Reagents; D013308:Streptonigrin; D006861:Hydrogen Peroxide; D006419:Heme Oxygenase (Decyclizing); D010100:Oxygen