Muc4/sialomucin complex in the mammary gland and breast cancer

Kermit L. Carraway, Shari A. Price-Schiavi, Masanobu Komatsu, Scott Jepson, Aymee Perez, Coralie A. Carothers Carraway

Research output: Contribution to journalReview articlepeer-review


MUC4 is a one of the membrane mucins of the mucin gene (MUC) family, characterized by mucin tandem repeat domains and a transmembrane domain which associates it with the cell plasma membrane. Although MUC4 is encoded by a single gene, it is produced by epithelial cells as a heterodimer through a proteolytic cleavage mechanism. This heterodimer is found in both membrane and soluble forms associated with epithelia. Functionally, MUC4 is proposed to provide a protective mechanism for vulnerable epithelia, such as those of the airway, eye, female reproductive tract and mammary gland. The protective mechanism(s) may be highjacked by some carcinomas, such as those of the breast, to increase tumor progression. Two mechanisms are proposed to contribute to the MUC4 functions. First, MUC4 acts as an anti-adhesive or anti-recognition barrier at epithelial or tumor cell surfaces. Second, MUC4 can bind the receptor tyrosine kinase ErbB2 and alter its cellular signaling. Expression of MUC4 in mammary gland is repressed by posttranscriptional mechanisms involving basement membrane and TGF-β, which are relieved during pregnancy to permit secretion of MUC4 into milk. These mechanisms are also abrogated in some breast cancers, providing a scenario for promotion of tumor progression. These observations imply important functions for MUC4 in both normal mammary function and in breast cancer.

Original languageEnglish (US)
Pages (from-to)323-337
Number of pages15
JournalJournal of Mammary Gland Biology and Neoplasia
Issue number3
StatePublished - Jul 2001
Externally publishedYes


  • Antiadhesion
  • Breast carcinoma
  • Epithelia
  • ErbB2
  • Mucin
  • Regulation

ASJC Scopus subject areas

  • Oncology
  • Cancer Research


Dive into the research topics of 'Muc4/sialomucin complex in the mammary gland and breast cancer'. Together they form a unique fingerprint.

Cite this