Decreased adherence of interleukin 6-treated breast carcinoma cells can lead to separation from neighbors after mitosis.
Interleukin 6 (IL-6) has been shown to inhibit the proliferation, but increase the motility, of wild-type ZR-75-1 human ductal breast carcinoma cells, a line of cells that resemble closely the malignant cells cultured from the ascitic effusion. IL-6-treated cells lose their epithelial character, become stellate or fusiform in shape, and migrate away from neighbors. In the wild-type ZR-75-1 cells, IL-6 causes cell-cell separation in preformed colonies as well as postmitotically. We have now investigated the action of IL-6 in clone B ZR-75-1 cells, which are morphologically distinct from wild-type ZR-75-1 cells. In the more polygonal rather than cuboidal clone B cells, IL-6 did not cause early inhibition of DNA synthesis and it caused little cell-cell separation in preformed colonies. However, IL-6 treatment markedly prolonged the interval between mitosis and readherence of daughter cells to their neighbors and the substratum. Supernatants from IL-6-treated cultures contained detached viable cells in increased numbers. Intermitotic intervals were prolonged in IL-6-treated cultures. IL-6-treated dividing breast carcinoma cells are characterized by an increased probability of separation from neighbors and the substratum.
Tamm
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Cell Physiology and Virology Laboratory, Rockefeller University, New York, NY 10021.
Cardinale
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Murphy
J S
JS
D001943:Breast Neoplasms / Q000473:pathology*; D002285:Carcinoma, Intraductal, Noninfiltrating / Q000473:pathology*; D002448:Cell Adhesion; D002455:Cell Division; D002465:Cell Movement; D004247:DNA / Q000096:biosynthesis; D005472:Fluorouracil / Q000494:pharmacology; D006801:Humans; D015850:Interleukin-6 / Q000494:pharmacology*; D008938:Mitosis; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D013997:Time Factors; D014407:Tumor Cells, Cultured
D015850:Interleukin-6; D004247:DNA; D013755:Tetradecanoylphorbol Acetate; D005472:Fluorouracil