ABSTRACT
F9 mouse teratocarcinoma cells have a high capacity to adhere to laminin and we identified alpha 6/beta 1 integrin as the principal laminin-binding protein present in these cells. F9 cells differentiated into parietal endoderm when monolayer cultures were treated with retinoic acid and dibutyryl cyclic AMP. In this process a decreased adherence to laminin was observed due to a lower expression of alpha 6/beta 1 integrin on the cell surface.
Subject(s)
Down-Regulation , Integrins/physiology , Laminin/physiology , Receptors, Laminin/physiology , Tretinoin/pharmacology , Animals , Bucladesine/pharmacology , Cell Adhesion , Cell Differentiation/drug effects , Integrin alpha6beta1 , Integrins/metabolism , Laminin/metabolism , Mice , Protein Binding , Receptors, Laminin/metabolism , Tumor Cells, Cultured/drug effectsABSTRACT
F9 mouse teratocarcinoma cells have a high capacity to adhere to laminin and we identified alpha6/beta1 integrin as the principal laminin-binding protein present in these cells. F9 cells differentiated into parietal endoderm when monolayer cultures were treated with retinoic acid and dibutyryl cyclic AMP. In this process a decreased adherence to laminin was observed due to a lower expression of alpha6/beta1 integrin on the cell surface
Subject(s)
Mice , Animals , Down-Regulation , Integrins/physiology , Laminin/physiology , Tretinoin/pharmacology , Cell Adhesion , Bucladesine/pharmacology , Cell Differentiation , Flow Cytometry , Integrins/metabolism , Laminin/metabolism , Protein Binding , Receptors, Laminin/metabolism , Receptors, Laminin/physiology , Tumor Cells, Cultured/drug effectsABSTRACT
The integrin family of adhesion receptors is likely to be important for tumor cell invasion and dissemination. We have studied the effects of the differentiating agents retinoic acid on integrin expression by the human melanoma cell line MeWo. Our results show that this agent inhibits cellular proliferation, increases melanin content and induces morphological changes in MeWo cells. Functionally, these alterations are associated with an enhanced adhesion to matrix protein vitronectin and higher levels of expression of vitronectin receptor on the cell surface. This is accompanied by increased levels of alpha v integrin mRNA. Although the mechanism by which retinoic acid regulates the expression of vitronectin receptor in MeWo cells needs further examination, this system may represent a good model for understanding the role of this receptor in melanoma progression, as well the molecular basis for retinoic acid therapy in these tumors.
