Conclusion
There is now evidence that tumor-promoting agents can interfere with natural cellular defense mechanisms at diverse developmental and functional levels, resulting in various, partly opposite consequences. Such findings are in keeping with the concept that tumor promoters interfere with the formation and growth of tumors by promoting cell transformation and by stimulating the multiplication and functional capacities of transformed cells on the one hand, and on the other by interfering with key cellular effector systems involved in the host's antitumor defense.
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Keller, R. Host defense mechanisms against tumors as the principal targets of tumor promoters. J Cancer Res Clin Oncol 105, 203–211 (1983). https://doi.org/10.1007/BF00395747
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DOI: https://doi.org/10.1007/BF00395747