develops from branched duct epithelial cell luminal epithelial cell of mammary gland 2010-09-20T01:37:53Z The luminal epithelial cells of the mammary gland are a key constituent of the glandular tissue in the mammalian breast. Packed into complex structures known as mammary ducts and lobules, these specialized cell types derive their nomenclature from their location within these units - specifically against the inner surface or 'lumen'. The main physiological functions they perform are the synthesis, storage, and secretion of milk. During lactation, these cells synthesize the various macromolecular constituents of milk, such as lipids, proteins, and lactose, which are then secreted into the ductal lumen. An intricately coordinated mix of hormonal activation and signaling pathways, involving prolactin and oxytocin amongst others, regulate this process. Luminal cells also exhibit receptivity towards estrogen, and their proliferation is influenced by estrogen and progesterone. Luminal epithelial cells are also engaged in several other key aspects of mammary gland biology. They carry a role in the formation of the ductal tree during the developmental process and are involved in glandular remodeling during pregnancy and post-weaning involution. Furthermore, luminal epithelial cells, just like other cell types in the breast, are susceptible to oncogenic transformation. In fact, the majority of breast cancers, specifically those classified as ductal carcinomas, are believed to originate from this cell population, underlining the pathophysiological significance of these cells. (This extended description was generated by ChatGPT and reviewed by the CellGuide team, who added references, and by the CL editors, who approved it for inclusion in CL. It may contain information that applies only to some subtypes and species, and so should not be considered definitional.) A mammary epithelial cell that occurs in the lumen of the ductal and alveoli structure in the breast. https://cellxgene.cziscience.com/cellguide/CL_0002326 FMA:73280 mature luminal cell mammary gland epithelial cell progenitor cell of mammary luminal epithelium