title: Incorporation of alphafetoprotein by the MCF-7 human breast cancer cell line.
abstract: The intracellular uptake of alphafetoprotein (AFP) and its fluorescein conjugates, by cultures of the MCF-7 human breast cancer cell line, has been demonstrated using an indirect immuno-peroxidase technique or by direct visualization under fluorescent lighting. The protein was localized in the cytoplasm. Ultrastructural autoradiographs of MCF-7 cells incubated with human 3H-AFP showed protein accumulation in several cytoplasmic organelles, particularly in lipid droplets. Nuclei were free of AFP. A significant species-specificity of AFP internalization was observed in comparative assays with human, mouse, pig and chicken AFP. The incorporation of the protein was prevented by incubation at 0 degrees C or by previous treatment of the cultures with 10nM sodium azide. Attention is paid to the reappearance in a human breast carcinoma cell line of a property associated during ontogenic development with ectodermal derivatives, including the epidermis.
mesh_terms: D000418:Albumins / Q000378:metabolism; D000818:Animals; D001345:Autoradiography; D001943:Breast Neoplasms / Q000378:metabolism*; D002460:Cell Line; D002645:Chickens; D016650:Fluorescein-5-isothiocyanate; D005452:Fluoresceins; D006801:Humans; D007124:Immunoenzyme Techniques; D051379:Mice; D012709:Serum Albumin / Q000378:metabolism; D013552:Swine; D013861:Thiocyanates; D000509:alpha-Fetoproteins / Q000378:metabolism*
chemical_list: D000418:Albumins; D005452:Fluoresceins; D012709:Serum Albumin; D013861:Thiocyanates; D000509:alpha-Fetoproteins; D016650:Fluorescein-5-isothiocyanate