Effects of Lactogenic Hormones on Morphological Development and Growth of Human Breast Epithelial Cells Cultivated in Collagen Gels

We investigated the hormonal dependence of the growth and morphological development of human breast epithelial cells (HBEC) cultivated in collagen gels floating on serum–free medium. HBEC used had grown out from breast carcinoma tissue and from histologically non–malignant tissue fragments in the same mastectomy specimens. In the presence of ail three lactogenic hormones, hydrocortisone (HC), insulin (INS), and prolactin (PRL), both carcinoma–derived and histologically non–malignant tissue–derived HBEC grew and formed cell masses with protruding tubule–like extensions that consisted of a multilayer of cells. Deletion of any one of the hormones from the medium had no effect on cell growth of HBEC derived from either tissue type. However, morphological development, especially the morphology of the tubule–like extensions, was altered in the histologically non–malignant tissue–derived HBEC by deletion of HC or INS, and by deletion of HC, but not INS, in the carcinoma–derived HBEC. The present results suggest that the carcinomaderived HBEC have decreased responsiveness to INS as compared to that of HBEC derived from histologically non–malignant breast tissue.