Skip to main content
. Author manuscript; available in PMC: 2009 Nov 5.
Published in final edited form as: Dev Cell. 2008 Apr;14(4):570–581. doi: 10.1016/j.devcel.2008.03.003

Figure 7. Mammary Epithelia Are in a Multilayered State during Morphogenesis.

Figure 7

(A) Early hyperplasias from the MMTV-PymT mouse model lose myoepithelial (ME) coverage and transition into a multilayered epithelial organization.

(B) Late hyperplasias from the MMTV-PymT mouse model have a multilayered epithelial organization and consist of incompletely polarized cells, with β-catenin on all lateral surfaces.

(C and D) Normal (C) FGF2-treated ducts in culture and (D) terminal end buds in vivo are multilayered and consist of incompletely polarized cells, with β-catenin on all lateral surfaces.

(E) Schematic representation of epithelial morphogenesis in culture.

(F) During normal morphogenesis, mammary epithelium transiently reorganizes into a highly proliferative, low-polarity, multilayered state and then returns to a quiescent, simple epithelial state. Aberrant entry into, or failure to exit from, this morphogenetically active state may facilitate tumor initiation or progression.

Scale bars are 20 μm.