Keeping abreast of the mammary epithelial hierarchy and breast tumorigenesis.
The epithelium of the mammary gland exists in a highly dynamic state, undergoing dramatic morphogenetic changes during puberty, pregnancy, lactation, and regression. The recent identification of stem and progenitor populations in mouse and human mammary tissue has provided evidence that the mammary epithelium is organized in a hierarchical manner. Characterization of these normal epithelial subtypes is an important step toward understanding which cells are predisposed to oncogenesis. This review summarizes progress in the field toward defining constituent cells and key molecular regulators of the mammary epithelial hierarchy. Potential relationships between normal epithelial populations and breast tumor subtypes are discussed, with implications for understanding the cellular etiology underpinning breast tumor heterogeneity.
Visvader
Jane E
JE
VBCRC (Victorian Breast Cancer Research Consortium) Laboratory, The Walter and Eliza Hall of Medical Research, Parkville, Victoria 3052, Australia. visvader@wehi.edu.au
D000818:Animals; D001943:Breast Neoplasms / Q000235:genetics / Q000473:pathology* / Q000503:physiopathology; D002454:Cell Differentiation; D005260:Female; D005786:Gene Expression Regulation; D006801:Humans; D008321:Mammary Glands, Animal / Q000166:cytology / Q000473:pathology* / Q000637:transplantation; D042361:Mammary Glands, Human / Q000166:cytology / Q000473:pathology*; D009154:Mutation / Q000235:genetics; D011247:Pregnancy; D013234:Stem Cells / Q000166:cytology; D044767:Ubiquitin-Protein Ligases / Q000235:genetics; D051153:Wnt Proteins / Q000378:metabolism
D051153:Wnt Proteins; C111164:BRAP protein, human; D044767:Ubiquitin-Protein Ligases