Inhibitory effects of transforming growth factor-beta on laminin production and growth exhibited by endoderm-like cells derived from embryonal carcinoma cells.
Previous studies have shown that two mouse embryonal carcinoma (EC) cell lines do not express cell surface receptors for transforming growth factor type-beta (TGF-beta) until they are induced to differentiate. To understand the effects of TGF-beta in this model system, we have examined the effects of TGF-beta on parietal endoderm-like cells derived from EC cells. We have determined that TGF-beta exerts three effects on these cells. TGF-beta inhibits proliferation of the parietal endoderm-like cells, and this occurs even in the presence of growth factors that stimulate their proliferation. TGF-beta also alters the morphology of the parietal endoderm-like cells by increasing their spreading. Moreover, the morphological effect of TGF-beta is observed in the presence of dibutyryl cyclic AMP (dbcAMP), which reduces the spreading of these cells. Lastly, TGF-beta, but not other growth factors, decreases the production of laminin by the parietal endoderm-like cells. This was unexpected since TGF-beta has been shown to increase the production of extracellular matrices in other systems. Thus, our findings indicate that parietal endoderm-like cells provide a useful system for broadening the study of TGF-beta. Furthermore, our findings provide additional support for the possibility that TGF-beta plays important roles during the early stages of mammalian development.
Kelly
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D
Eppley Institute for Research in Cancer and Allied Diseases, University of Nebraska Medical Center, Omaha 68105.
Rizzino
A
A
D000818:Animals; D002460:Cell Line; D002465:Cell Movement / Q000187:drug effects; D002471:Cell Transformation, Neoplastic / Q000187:drug effects*; D004707:Endoderm / Q000187:drug effects / Q000378:metabolism / Q000473:pathology*; D007797:Laminin / Q000378:metabolism*; D051379:Mice; D013724:Teratoma / Q000378:metabolism / Q000473:pathology*; D015291:Transforming Growth Factors / Q000494:pharmacology*; D014407:Tumor Cells, Cultured / Q000187:drug effects / Q000378:metabolism / Q000473:pathology
D007797:Laminin; D015291:Transforming Growth Factors