Breast Epithelial Cells In Culture Research Articles

Biochemical and Histological Characterization of Antigens Preferentially Expressed on the Surface and Cytoplasm of Breast Carcinoma Cells Identified by Monoclonal Antibodies Against the Human Milk Fat Globule

The preparation of monoclonal antibodies (MAbs) against the human milk fat globule membrane with preferential binding to breast carcinoma cells is described. Using BALB/c mouse myeloma cells; inter-specific, intra-strain, and inter-strain hybridomas were isolated that identified three different components of the human milk fat globule of approximately 46,000, and 70,000 daltons and a mucin-like glycoprotein complex (NPGP) ranging from 400,000 to over a million daltons, respectively. Three MAbs (BrE1, BrE2, BrE3) identified the latter component which consists of at least three different size molecules for which the aforementioned MAb's have different binding specificities. MAbs, BrE2 and BrE3, bound to normal breast epithelial cells but to a lesser extent than to tumors and only at the apical surface facing the lumen, while they bound breast carcinomas strongly, and often in the cytoplasm as well as on the surface. Higher concentrations of BrE3 were required to stain normal breast compared to breast tumors. BrE1 also stained breast carcinomas both on the surface and cytoplasmically but did not stain normal breast tissue. The MAb, Mc13, as well as the previously reported MAb McR2, both against the 70,000 dalton component, did not significantly stain either normal or cancerous breast tissue in histological sections but did bind significantly to cultured breast epithelial cells and to the milk fat globule membrane. The MAbs, Mc8 and Mc3, reported previously to be against the 46,000 dalton component, stained histologically only malignant breast tissue but only weakly; however, they bound strongly to intact breast carcinoma cells and breast cell membrane preparations with a radioimmunobinding assay. These MAbs should be useful in characterizing the surface of breast epithelial cells, studying surface alterations in malignancy, and possibly in breast cancer diagnosis and therapy.

Progestin Effect on Cell Proliferation and 17β-Hydroxysteroid Dehydrogenase Activity in Normal Human Breast Cells in Culture*

In contrast to cancer cell lines, normal human breast epithelial cells are infrequently studied. Such cells, now routinely cultured in our laboratory from tissue obtained at the time of reduction mammoplasty, were used to study the actions of estradiol (E2), the progestin promegestone (R5020), and the antiprogesterone RU486 on cell growth and progesterone-dependent 17 beta-hydroxysteroid dehydrogenase (E2DH) activity, which is considered good marker of epithelial differentiation as well as progesterone dependency. The studies were carried out using secondary cultures to assure equal initial cell distribution. Cell growth was estimated daily by a histometric method providing a growth index and DNA assay. E2 stimulation of cell growth was not found when the cells were grown in our usual culture medium, but E2 dose-dependent growth stimulation occurred in medium minimally supplemented with serum (1%), insulin; and epidermal growth factor. R5020 inhibited cell growth and stimulated E2DH activity in a dose-dependent manner. RU486 behaved as a pure but low potent progestin agonist concerning E2DH stimulation, but as an agonist with partial antagonist properties concerning cell growth inhibition. In conclusion, E2 stimulated proliferation of human breast epithelial cells in culture, whereas the progestin R5020 inhibited cell multiplication and favored differentiation. The antiprogesterone RU486 had a biphasic effect acting both as progestin agonist and partial antagonist.

Dual agonist and antagonist properties of RU486 on normal human breast epithelial cells in culture

Dual agonist and antagonist properties of RU486 on normal human breast epithelial cells in culture

Preparation and identification of human breast epithelial cells in culture

The routine preparation of gram quantities of lobuloalveolar and ductal structures from human reduction mammaplasties by treatment with collagenase is described. When cultured on plastic or glass surfaces these structures give rise, initially, to epithelial sheets consisting of cells which retain many morphological characteristics of myoepithelial cells and do not stain with an antiserum which reacts with the surfaces of the lining epithelium of breast ducts and lobulo-alveoli. Subsequently, cells which resemble the lining epithelial cells migrate from these structures and react strongly with the antiserum. Cell proliferation in these cultures is minimal. Explants of major ducts dissected from mastectomies produce vigorously proliferating epithelial sheets which contain morphologically similar cells not identifiable as either lining epithelium or myoepithelium, although nearly all the cells in direct contact with the medium react with the lining epithelium specific antiserum.