Changes in ErbB2 (her-2/neu), ErbB3, and ErbB4 during growth, differentiation, and apoptosis of normal rat mammary epithelial cells

Kathleen M. Darcy, Danilo Zangani, Ann L. Wohlhueter, Ruea Yea Huang, Mary M. Vaughan, Joy A. Russell, Margot M. Ip*

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

44 Scopus citations


Studies were undertaken to examine the natural role of ErbB2, ErbB3, and ErbB4 during the development of normal rat mammary epithelial cells (MECs) in vivo and in vitro. Immunohistochemical analysis demonstrated that mammary gland terminal end buds expressed abundant ErbB2 and ErbB4 but limited ErbB3 in pubescent rats, whereas luminal epithelial cells in nulliparous rats expressed ErbB2, ErbB3, and/or ErbB4. During pregnancy, ductal epithelial cells and stromal cells expressed abundant ErbB3 but limited ErbB2. Although ErbB2 and ErbB3 were downregulated throughout lactation, both receptors were re-expressed during involution. In contrast, ErbB4 was downregulated throughout pregnancy, lactation, and involution. Immunoblotting and immunoprecipitation studies confirmed the developmental expression of ErbB2 and ErbB3 in the mammary gland and the co-localization of distinct ErbB receptors in the mammary gland of nulliparous rats. In agreement with our in vivo findings, primary culture studies demonstrated that ErbB2 and ErbB3 were expressed in functionally immature, terminally differentiated and apoptotic MECs, and downregulated in functionally differentiated MECs. ErbB receptor signaling was required for epithelial cell growth, functional differentiation, and morphogenesis of immature MECs, and the survival of terminally differentiated MECs. Finally, ErbB4 expression did not interfere with functional differentiation and apoptosis of normal MECs.

Original languageEnglish
Pages (from-to)63-80
Number of pages18
JournalJournal of Histochemistry and Cytochemistry
Issue number1
StatePublished - Jan 2000
Externally publishedYes


  • EGF receptor
  • ErbB3
  • ErbB4
  • Her-2/neu
  • Immunocytochemistry
  • Immunohistochemistry
  • Mammary breast ErbB2


Dive into the research topics of 'Changes in ErbB2 (her-2/neu), ErbB3, and ErbB4 during growth, differentiation, and apoptosis of normal rat mammary epithelial cells'. Together they form a unique fingerprint.

Cite this