Syndecan-1, is a transmembrane heparan/chondroitin sulfate proteoglycan necessary
for cell-cell and cell-matrix interactions. Its decreased level on the cell surface
correlates with poor prognosis in several tumor types. Aberrant stromal localization
of syndecan-1 is also considered an unfavorable prognostic factor in various human
malignancies. In the presented work the question was addressed if changes in syndecan-1
expression are related to the prognosis of cervical cancer. Immunohistochemistry for
syndecan-1 extracellular domain was performed on surgical specimens of primary cervical
cancer. To follow the communication between tumor cells and stromal fibroblasts, their
mono-and co-cultures were studied, detecting the expression of syndecan-1, smooth
muscle actin, vimentin, and desmin. Immunohistochemistry of tumorous specimens revealed
that while cell surface syndecan-1 expression was reduced on cancer cells, it appeared
on the surface of tumor-associated fibroblasts. Until year 7, the cohort with high
cell surface syndecan-1 expression had significantly longer survival. No difference
in the same time-period could be detected when stromal syndecan-1 expression was analyzed.
In vitro analysis revealed, that tumor cells can induce syndecan-1 expression on fibroblast,
and fibroblasts showed that fibroblast-like cells are built by two cell types: (a)
syndecan-1 positive, cytokeratin negative real fibroblasts, and (b) syndecan-1 and
cytokeratin positive epithelial-mesenchymal transformed tumor cells. Syndecan-1 on
the surface of cancer cells appears to be a positive prognostic marker. Although syndecan-1
positive fibroblasts promote tumor cell proliferation in vitro, we failed to detect
their cancer promoting effect in vivo.
