%0 Journal Article
%T Tumour-stromal interactions: Transforming growth factor-beta isoforms and hepatocyte growth factor/scatter factor in mammary gland ductal morphogenesis
%A Jeffrey W Pollard
%J Breast Cancer Research
%D 2001
%I BioMed Central
%R 10.1186/bcr301
%X The development of the mammary gland largely occurs postnatally. Initially, the ductal system begins to develop from the nipple, and is characterized by specialized structures - the terminal end buds (TEBs) ¨C capping the end of the ducts. TEBs grow out across the fat pad and, by bifurcation, lay down by puberty the minimally branched structure that covers the fat pad, at which point the TEBs disappear. Throughout the estrus cycle there is modest development of the ductal system, but it is during pregnancy that a dramatic outgrowth of secondary branches occurs that, together with the formation of the lobuloalveolar structures, results in the milk-producing gland. Once weaning has occurred, this fully developed structure regresses to a virgin-like state.It has been well established that these events are under the control of a complex interplay of circulating hormones, particularly estrogen, progesterone, glucocorticoids and prolactin gene family members [1]. However, it has also become clear that local mesenchymal¨Cepithelial interactions are essential for mammary development, and that many of these are mediated by growth factors that are often synthesized in response to the circulating hormones. These include wnt family proteins, TGF-¦Á, fibroblast growth factors, insulin-like growth factors, epidermal growth factor [2], colony stimulating factor-1 [3], and ¨C the subjects of the present review ¨C the TGF-¦Â family of proteins and HGF/SF.The three classical members of the TGF-¦Â family belong to a much larger family. In humans this family contains almost 30 members, including bone morphogenic proteins, activins, and Mullerian inhibiting substance [4]. These TGF-¦Â family members have profound effects during development, regulating cell fate by affecting proliferation, differentiation and cell death, and therefore they are important for the development of many tissues.All three of the classical TGF-¦Â isoforms (TGF-¦Âs) activate intracellular responses by binding to and hetero
%K apoptosis
%K ductal morphogenesis
%K growth factor
%K mammary gland
%K SMAD
%U http://breast-cancer-research.com/content/3/4/230