TY - JOUR
T1 - Overexpression of manganese-containing superoxide dismutase confers resistance to the cytotoxicity of tumor necrosis factor α and/or hyperthermia
AU - Li, Jian-Jian
AU - Oberley, Larry W.
PY - 1997/5/15
Y1 - 1997/5/15
N2 - Human breast cancer cells (MCF-7) overexpressing manganesecontaining superoxide dismutase (MnSOD) by stable or transient transfection were challenged with the cytotoxicity of tumor necrosis factor (TNF-α), hyperthermia, and a combination of both. In contrast to the vector control and wild-type MCF-7 cells, the stable MnSOD transfectants showed significant resistance to the cytotoxicity of TNF-α (100 units/ml), heat at 43 or 45°C, and a combination of TNF-α and heat at 43°C. To probe the correlation of MnSOD levels with cell survival, cell sensitivity to TNF-α, heat at 43°C, or a combination of both was also measured after MnSOD cDNA transient transfection. The data showed that the level of cell resistance was proportional to the exogenous MnSOD gene expression. These results suggest that superoxide free radicals or their reaction products are responsible for much of the synergistic cytotoxicity of TNF-α and hyperthermia.
AB - Human breast cancer cells (MCF-7) overexpressing manganesecontaining superoxide dismutase (MnSOD) by stable or transient transfection were challenged with the cytotoxicity of tumor necrosis factor (TNF-α), hyperthermia, and a combination of both. In contrast to the vector control and wild-type MCF-7 cells, the stable MnSOD transfectants showed significant resistance to the cytotoxicity of TNF-α (100 units/ml), heat at 43 or 45°C, and a combination of TNF-α and heat at 43°C. To probe the correlation of MnSOD levels with cell survival, cell sensitivity to TNF-α, heat at 43°C, or a combination of both was also measured after MnSOD cDNA transient transfection. The data showed that the level of cell resistance was proportional to the exogenous MnSOD gene expression. These results suggest that superoxide free radicals or their reaction products are responsible for much of the synergistic cytotoxicity of TNF-α and hyperthermia.
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M3 - Article
C2 - 9157996
AN - SCOPUS:0030968919
VL - 57
SP - 1991
EP - 1998
JO - Journal of Cancer Research
JF - Journal of Cancer Research
SN - 0099-7013
IS - 10
ER -