Amphiregulin mediates self-renewal in an immortal mammary epithelial cell line with stem cell characteristics.
Amphiregulin (AREG), a ligand for epidermal growth factor receptor, is required for mammary gland ductal morphogenesis and mediates estrogen actions in vivo, emerging as an essential growth factor during mammary gland growth and differentiation. The COMMA-D beta-geo (CDbetageo) mouse mammary cell line displays characteristics of normal mammary progenitor cells including the ability to regenerate a mammary gland when transplanted into the cleared fat pad of a juvenile mouse, nuclear label retention, and the capacity to form anchorage-independent mammospheres. We demonstrate that AREG is essential for formation of floating mammospheres by CDbetageo cells and that the mitogen activated protein kinase signaling pathway is involved in AREG-mediated mammosphere formation. Addition of exogenous AREG promotes mammosphere formation in cells where AREG expression is knocked down by siRNA and mammosphere formation by AREG(-/-) mammary epithelial cells. AREG knockdown inhibits mammosphere formation by duct-limited mammary progenitor cells but not lobule-limited mammary progenitor cells. These data demonstrate AREG mediates the function of a subset of mammary progenitor cells in vitro.
Booth
Brian W
BW
Mammary Biology and Tumorigenesis Laboratory, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA. brbooth@clemson.edu
Boulanger
Corinne A
CA
Anderson
Lisa H
LH
Jimenez-Rojo
Lucia
L
Brisken
Cathrin
C
Smith
Gilbert H
GH
D066258:Amphiregulin; D000818:Animals; D002461:Cell Line, Transformed; D049109:Cell Proliferation; D066255:EGF Family of Proteins; D004847:Epithelial Cells / Q000166:cytology* / Q000201:enzymology / Q000378:metabolism*; D005260:Female; D006023:Glycoproteins / Q000037:antagonists & inhibitors / Q000172:deficiency / Q000378:metabolism*; D036341:Intercellular Signaling Peptides and Proteins / Q000172:deficiency / Q000378:metabolism*; D008321:Mammary Glands, Animal / Q000166:cytology*; D051379:Mice; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism; D034741:RNA, Small Interfering / Q000378:metabolism; D013234:Stem Cells / Q000166:cytology* / Q000378:metabolism*; D014162:Transfection
D066258:Amphiregulin; C587849:Areg protein, mouse; D066255:EGF Family of Proteins; D006023:Glycoproteins; D036341:Intercellular Signaling Peptides and Proteins; D034741:RNA, Small Interfering; D020928:Mitogen-Activated Protein Kinases