%0 Journal Article
%T Tumour-stromal interactions: Reciprocal regulation of extracellular matrix proteins and ovarian steroid activity in the mammary gland
%A Sandra Z Haslam
%A Terry L Woodward
%J Breast Cancer Research
%D 2001
%I BioMed Central
%R 10.1186/bcr324
%X Postnatal mammary gland development and function are highly dependent upon the actions of the ovarian hormones, estrogen and progesterone [1]. In estrogen receptor knockout (ERKO) mice only a rudimentary mammary gland is present at birth and no further development occurs postnatally [2]. To determine whether estrogen receptor (ER) is required in stromal tissue, epithelial tissue or both for normal mammary gland development, Cunha et al. [3] have surgically transplanted wild-type (ER+/+) or ERKO (ER-/-) epithelial tissue with wild-type or ERKO stromal tissue under the kidney capsule of athymic nude mice. These authors reported that ER+/+ stroma was required for normal mammary ductal morphogenesis, but ER+/+ epithelium was not. These results corroborate in vitro studies that have demonstrated that estrogen-dependent mammary epithelial proliferation and/or ductal morphogenesis is mediated through the paracrine action of estrogen-induced, stroma-derived factors. Stromal cells appear to influence epithelial cell behavior by the secretion of growth factors and/or by altering the composition of the extracellular matrix (ECM) in which epithelial cells reside [4,5,6]. Previously we have reviewed the regulation and action of autocrine and paracrine growth factors (including the epidermal growth factor, insulin-like growth factor, hepatocyte growth factor and fibroblast growth factor families) involved in ovarian steroid-mediated epithelial¨Cstromal interactions [4]. A recent report has also demonstrated that keratinocyte growth factor mRNA and protein are increased by estrogen in mammary stroma, although it is not clear what effect keratinocyte growth factor has on mammary gland development or differentiation [7]. In the past few years, several studies have revealed information about basement membrane (BM) ECM proteins and their cellular receptors: they regulate cell proliferation, differentiation and apoptosis; they are secreted and/or regulated by complex epithelial¨Cstromal
%K breast cancer
%K estrogen
%K extracellular matrix
%K integrins
%K progesterone
%U http://breast-cancer-research.com/content/3/6/365