Mammary gland epithelial cell

Mammary gland epithelial cells form the bilayered structure of the mammary ducts and alveoli, consisting of an inner luminal layer responsible for milk secretion and an outer basal/myoepithelial layer that provides contractile support for milk ejection. These cells drive ductal elongation, branching morphogenesis, and alveolar development during puberty, pregnancy, and lactation through interactions with hormones like estrogen, progesterone, prolactin, and signaling pathways including Wnt/β-catenin, FGF, and PTHrP. They respond to stromal cues from adipocytes, fibroblasts, and extracellular matrix to regulate proliferation, differentiation, porosity. In disease, particularly breast cancer, these cells undergo epithelial-to-mesenchymal transition, losing tumor-suppressive functions of myoepithelial cells, which normally inhibit invasion by maintaining basement membrane integrity. While not direct therapeutic targets like receptors or enzymes, their dysregulation contributes to oncogenesis, with luminal progenitors implicated in tumor initiation.

Other names

mammary epithelial cell (MEC)breast epithelial cell