Activation of EGF receptor family members suppresses the cytotoxic effects of tumor necrosis factor-alpha.
Tumor necrosis factor (TNF)-alpha has a broad range of biological activities, which depend heavily on cell type and physiological condition. In a panel of human tumor cell lines we analyzed expression of the receptor tyrosine kinases EGFR, ErbB2 and ErbB3, and the response to TNF-alpha. Among the cell lines tested those resistant to TNF-alpha were found to express high levels of either EGFR, or ErbB2 and ErbB3. In TNF-sensitive breast and cervical carcinoma cells activation of EGFR or ErbB2 by the exogenous growth factors EGF and heregulin beta1 resulted in a significant increase in the number of cells surviving TNF-alpha treatment. In contrast, inhibition of EGFR activation in TNF-resistant breast carcinoma cells by the novel antagonistic anti-EGFR antibody 14E1 sensitized the cells to the cytotoxic effects of TNF-alpha. A bacterially expressed fusion protein consisting of a 14E1 single-chain (sc) Fv antibody fragment linked to human TNF-alpha retained TNF-alpha activity. This scFv(14E1)-TNF-alpha molecule localized specifically to EGFR on the surface of tumor cells and activated the NF-kappaB pathway in co-cultured T cells, as demonstrated by electrophoretic mobility shift assays.
Hoffmann
M
M
Institute for Experimental Cancer Research, Tumor Biology Center, Freiburg, Germany.
Schmidt
M
M
Wels
W
W
D000818:Animals; D001943:Breast Neoplasms; D002277:Carcinoma; D018920:Coculture Techniques; D004351:Drug Resistance; D066246:ErbB Receptors / Q000378:metabolism*; D005260:Female; D006801:Humans; D018796:Immunoconjugates / Q000378:metabolism; D007128:Immunoglobulin Fragments / Q000378:metabolism; D051379:Mice; D016328:NF-kappa B / Q000378:metabolism; D011485:Protein Binding; D011518:Proto-Oncogene Proteins / Q000378:metabolism*; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000378:metabolism*; D020893:Receptor, ErbB-3; D013601:T-Lymphocytes / Q000166:cytology; D014407:Tumor Cells, Cultured; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism / Q000633:toxicity*
D066246:ErbB Receptors; D018796:Immunoconjugates; D007128:Immunoglobulin Fragments; D016328:NF-kappa B; D011518:Proto-Oncogene Proteins; D018719:Erb-b2 Receptor Tyrosine Kinases; D020893:Receptor, ErbB-3; D014409:Tumor Necrosis Factor-alpha; C055966:immunoglobulin Fv