Endothelial cells stimulate growth of normal and cancerous breast epithelial cells in 3D culture
1 Stem cell research unit, Department of anatomy, Faculty of medicine, University of Iceland and Department of laboratory hematology, Landspitali, university hospital, (Vatnsmýrarvegur 16), Reykjavík, (101), Iceland
2 Department of cellular and molecular medicine, Faculty of health science, Copenhagen University, (Blegdamsvej 3), Copenhagen, (2200), Denmark
3 Department of pathology, Landspitali, university hospital, (building 7/8), Reykjavik, (101), Iceland
4 St. Josefs hospital, (Suðurgata 41), Hafnarfjörður, (220), Iceland
5 Department of pharmacology and toxicology, Faculty of medicine, University of Iceland, (Hofsvallagata 53), Reykjavík, (101), Iceland
BMC Research Notes 2010, 3:184 doi:10.1186/1756-0500-3-184Published: 7 July 2010
Epithelial-stromal interaction provides regulatory signals that maintain correct histoarchitecture and homeostasis in the normal breast and facilitates tumor progression in breast cancer. However, research on the regulatory role of the endothelial component in the normal and malignant breast gland has largely been neglected. The aim of the study was to investigate the effects of endothelial cells on growth and differentiation of human breast epithelial cells in a three-dimensional (3D) co-culture assay.
Breast luminal and myoepithelial cells and endothelial cells were isolated from reduction mammoplasties. Primary cells and established normal and malignant breast cell lines were embedded in reconstituted basement membrane in direct co-culture with endothelial cells and by separation of Transwell filters. Morphogenic and phenotypic profiles of co-cultures was evaluated by phase contrast microscopy, immunostaining and confocal microscopy.
In co-culture, endothelial cells stimulate proliferation of both luminal- and myoepithelial cells. Furthermore, endothelial cells induce a subpopulation of luminal epithelial cells to form large acini/ducts with a large and clear lumen. Endothelial cells also stimulate growth and cloning efficiency of normal and malignant breast epithelial cell lines. Transwell and gradient co-culture studies show that endothelial derived effects are mediated - at least partially - by soluble factors.
Breast endothelial cells - beside their role in transporting nutrients and oxygen to tissues - are vital component of the epithelial microenvironment in the breast and provide proliferative signals to the normal and malignant breast epithelium. These growth promoting effects of endothelial cells should be taken into consideration in breast cancer biology.