Ultrastructural Study of Human Mammary Carcinoma Cells (MCF-7) Grown in Collagen-Coated Sponge

MCF-7 is an established cell line derived from a mammary carcinoma, that reproduces the tumor histological pattern when cultured in collagen-coated cellulose sponge.Cells grown in monolayer for more than 120 passages are seeded in a collagen-coated cellulose sponge and cultured in Eagle's nutrient medium, supplemented with insulin and 10% calf serum for 7 to 14 days. The sponges were fixed in Hirsch-Fedorko, embedded in Epon, and sectioned for electron microscopy.The cells are observed growing in clusters of 4 to 50 cells per level of section and also acinar-like structures.A common ultrastructual pattern can be described for most of the cells. The cell surface presents numerous microvilli, that have a positive ATPase histochemical reaction. The cells are joined by desmosomes, intermediary, and tight junctions with cell interdigitations among them, but no junctions are observed between the cells and the collagen coat (Fig. 3).</jats:p