Syndecan-1 expression is induced in the stroma of infiltrating breast carcinoma

Am J Clin Pathol. 1999 Sep;112(3):377-83. doi: 10.1093/ajcp/112.3.377.


Loss of expression of the heparan sulfate proteoglycan syndecan-1 leads to reduced cell adhesion, increased invasive potential, and dysregulated growth of mammary epithelial cells in vitro. We compared syndecan-1 expression in malignant and nonmalignant breast tissues using immunohisto-chemistry with monoclonal antibody B-B4. Staining for syndecan-1 is greatly diminished on malignant cells within infiltrating ductal carcinomas (n = 20) as compared with ductal epithelium of both normal breast (n = 14) and stromal-epithelial neoplasms (n = 10), which exhibit extensive basolateral epithelial staining. Surprisingly, comparison of malignant and nonmalignant breast tissue also reveals a striking difference in expression of syndecan-1 within the stromal compartment. In infiltrating ductal carcinomas, strong staining for syndecan-1 is present both within the connective tissue and on stromal cell surfaces, whereas syndecan-1 expression is absent in the stroma of both normal breast and stromal-epithelial neoplasms. Because syndecan-1 interacts with heparin-binding growth factors such as FGF-2, accumulation of syndecan-1 within the tumor stroma may contribute to the extensive angiogenesis and stromal proliferation characteristic of infiltrating breast carcinoma. Moreover, the induction of syndecan-1 within the stroma, coupled with the loss of syndecan-1 on malignant cells, suggests that changes in syndecan-1 expression are critical in promoting the metastatic phenotype of infiltrating ductal carcinoma of the breast.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Breast Neoplasms / metabolism*
  • Carcinoma, Ductal, Breast / metabolism*
  • Carcinoma, Ductal, Breast / pathology
  • Case-Control Studies
  • Female
  • Fibroadenoma / metabolism*
  • Fibroadenoma / pathology
  • Humans
  • Membrane Glycoproteins / biosynthesis*
  • Neoplasm Proteins / biosynthesis*
  • Proteoglycans / biosynthesis*
  • Stromal Cells / metabolism
  • Syndecan-1
  • Syndecans


  • Membrane Glycoproteins
  • Neoplasm Proteins
  • Proteoglycans
  • SDC1 protein, human
  • Syndecan-1
  • Syndecans