title: Reconstitution of mammary gland development in vitro: requirement of c-met and c-erbB2 signaling for branching and alveolar morphogenesis.
abstract: We have established a cell culture system that reproduces morphogenic processes in the developing mammary gland. EpH4 mouse mammary epithelial cells cultured in matrigel form branched tubules in the presence of hepatocyte growth factor/scatter factor (HGF/SF), the ligand of the c-met tyrosine kinase receptor. In contrast, alveolar structures are formed in the presence of neuregulin, a ligand of c-erbB tyrosine kinase receptors. These distinct morphogenic responses can also be observed with selected human mammary carcinoma tissue in explant culture. HGF/SF-induced branching was abrogated by the PI3 kinase inhibitors wortmannin and LY294002. In contrast, neuregulin- induced alveolar morphogenesis was inhibited by the MAPK kinase inhibitor PD98059. The c-met-mediated response could also be evoked by transfection of a c-met specific substrate, Gab1, which can activate the PI3 kinase pathway. An activated hybrid receptor that contained the intracellular domain of c-erbB2 receptor suffices to induce alveolar morphogenesis, and was observed in the presence of tyrosine residues Y1028, Y1144, Y1201, and Y1226/27 in the substrate-binding domain of c-erbB2. Our data demonstrate that c-met and c-erbB2 signaling elicit distinct morphogenic programs in mammary epithelial cells: formation of branched tubules relies on a pathway involving PI3 kinase, whereas alveolar morphogenesis requires MAPK kinase.
authors.affiliation: Max-Delbrück-Center for Molecular Medicine, D-13122 Berlin, Germany.
authors.forename: C
authors.initials: C
authors.lastname: Niemann
authors.forename: V
authors.initials: V
authors.lastname: Brinkmann
authors.forename: E
authors.initials: E
authors.lastname: Spitzer
authors.forename: G
authors.initials: G
authors.lastname: Hartmann
authors.forename: M
authors.initials: M
authors.lastname: Sachs
authors.forename: H
authors.initials: H
authors.lastname: Naundorf
authors.forename: W
authors.initials: W
authors.lastname: Birchmeier
mesh_terms: D000730:Androstadienes / Q000494:pharmacology; D000818:Animals; D001943:Breast Neoplasms; D017871:Calcium-Calmodulin-Dependent Protein Kinases / Q000378:metabolism; D015815:Cell Adhesion Molecules / Q000502:physiology; D002867:Chromones / Q000494:pharmacology; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005419:Flavonoids / Q000494:pharmacology; D006023:Glycoproteins / Q000502:physiology; D017228:Hepatocyte Growth Factor / Q000502:physiology; D006801:Humans; D008321:Mammary Glands, Animal / Q000166:cytology / Q000196:embryology* / Q000201:enzymology; D051379:Mice; D008854:Microscopy, Electron; D009024:Morphogenesis / Q000502:physiology; D009025:Morpholines / Q000494:pharmacology; D020880:Neuregulins; D019869:Phosphatidylinositol 3-Kinases / Q000378:metabolism; D019859:Proto-Oncogene Proteins c-met / Q000502:physiology*; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000502:physiology*; D015398:Signal Transduction / Q000187:drug effects / Q000502:physiology*; D014407:Tumor Cells, Cultured / Q000166:cytology / Q000201:enzymology / Q000648:ultrastructure; D000077191:Wortmannin
chemical_list: D000730:Androstadienes; D017871:Calcium-Calmodulin-Dependent Protein Kinases; D015815:Cell Adhesion Molecules; D002867:Chromones; D004791:Enzyme Inhibitors; D005419:Flavonoids; D006023:Glycoproteins; D017228:Hepatocyte Growth Factor; D009025:Morpholines; D020880:Neuregulins; D019869:Phosphatidylinositol 3-Kinases; D019859:Proto-Oncogene Proteins c-met; D018719:Erb-b2 Receptor Tyrosine Kinases; D000077191:Wortmannin; C085911:2-(4-morpholinyl)-8-phenyl-4H-1-benzopyran-4-one; C093973:2-(2-amino-3-methoxyphenyl)-4H-1-benzopyran-4-one