The Mouse Adult Gross Anatomy Ontology and Mammalian Phenotype Ontology are downloaded weekly from the Mouse Genome Informatics databases at Jackson Laboratories (ftp://ftp.informatics.jax.org/pub/reports/index.html). For more information about these ontologies, see the MGI Publications Page at http://www.informatics.jax.org/mgihome/other/publications.shtml.
any functional anomaly of the outer cell layer of the mammary gland epithelium bilayer which is located basal to the luminal (secretory) cells and adjacent to the basement membrane; basal cells (aka myoepithelial cells or MECs) are specialized epithelial cells that express smooth muscle-specific contractile and cytoskeletal properties; during lactation, MECs contract in response to oxytocin to generate the contractile force required for milk ejection; MECs are involved in all developmental stages of mammary gland morphogenesis, modulating proliferation and differentiation of luminal cells; they take part in the formation of extracellular matrix, synthesizing its components and secreting proteinases and their inhibitors; in addition, MECs are regarded as natural cancer suppressors: they secrete suppressor proteins limiting cancer growth, invasiveness, and neoangiogenesis; MECs are markedly resistant to malignant transformation and they are able to suppress the transformation of neighboring luminal cells