期刊名称:Proceedings of the National Academy of Sciences
印刷版ISSN:0027-8424
电子版ISSN:1091-6490
出版年度:1981
卷号:78
期号:1
页码:382-386
DOI:10.1073/pnas.78.1.382
语种:English
出版社:The National Academy of Sciences of the United States of America
摘要:Primary cultures of rat mammary epithelial cells proliferate and synthesize basement membrane collagen (type IV collagen) in a serum-free medium supplemented with epidermal growth factor (EGF), hydrocortisone or dexamethasone, insulin, transferrin, and Pedersen fetuin. The growth response of the cells to EGF and glucocorticoids but not to insulin or transferrin varies depending on the substratum on which the cells are plated. Cell growth is 4 times more sensitive to omission of EGF or glucocorticoid on type I collagen or plastic substratum than on type IV collagen substratum. The mechanism by which these two growth factors differentially affect cell growth appears to be linked to an increase in type IV collagen synthesis and a stabilization of secreted type IV collagen in the extracellular matrix. Glucocorticoids suppress the elaboration of type IV collagenolytic activity by the cells whereas EGF stimulates amino acid incorporation into type IV collagen. The results suggest that EGF and glucocorticoids affect mammary epithelial cell growth by facilitating the accumulation of the appropriate cell substratum.