TRANSFORMATION OF HUMAN BREAST EPITHELIAL CELLS IN VITRO

点击翻译按钮获取中文摘要

Our long term objective is to induce preneoplastic and neoplastic transformation of human mammary epithelial cells, under defined in vitro conditions, with direct- and indirect-acting chemical carcinogens. An ability to consistently transform human mammary cells under defined in vitro conditions is essential to designing experiments to understand the cellular-molecular events underlying transformation and histogenesis of human breast cancer(s). Our strategy is to transform human epithelial cells grown under serum- free conditions in a collagen gel culture system, as well as in monolayer culture systems using various matrices. Specifically, we will: a) analyze the growth regulation of normal, benign (fibrocystic) and carcinomatous human mammary cells in collagen culture, under serum-free conditions in the presence of hormones (estrogen, progesterone, prolactin, etc.), growth factors (EGF, FGF, TGF alpha, TGF beta, etc.) and nonhormonal agents (lipids, TPA, Li+); b) use these endpoints to design culture conditions which facilitate human mammary epithelial cell transformation at high yield, in a manner similar to those developed for transformation of murine epithelial cells; c) use cDNA probes to determine whether amplification, rearrangement or expression of plasminogen activators (tPA, urokinase), TGF alpha, TGF beta, EGF receptor, glutathione-s-transferase-P, gamma-glutamyl transpeptidase and 0-6 alkyl-DNA-alkyltransferase are reliable, quantitative molecular markers for transformation and tumor histogenesis; d) determine whether changes at the molecular level correlate with phenotype changes (karyotypic, immunocytochemical, ultramicroscopic); e) develop suitable in vitro and in vivo assay systems to identify those molecular-cellular changes which represent preneoplastic and neoplastic (malignant) transformants. Our experience and approach suggest that development of a system(s) for transformation of human mammary epithelial cell in vitro is an achievable goal.