Klin Padiatr 2004; 216 - 8
DOI: 10.1055/s-2004-828553

Clear cell sarcoma of soft parts (CCSST): functional analysis of ERBB3

K Brachwitz 1, KL Schaefer 1, Y Braun 1, HE Gabbert 1, C Poremba 1
  • 1Department of Pathology, University of Duesseldorf, Germany

CCSST, a rare and slowly growing tumor usually affecting adolescents and young adults, have been shown to overexpress the member of the EGF-receptor family ERBB3 by expression profile analysis of corresponding tumor cell lines. Therefore we sought to investigate the impact of this gene for tumor cell activation and proliferation.

All eight CCSST cell lines could be shown to dramatically overexpress ERBB3 mRNA and protein while ERBB2 protein expression was found to be week. By immunohistochemistry primary tumor biopsies also stain positive for ERBB3.

We found that CCSST may be stimulated by the ERBB3-ligand heregulin which could be shown by receptor tyrosine phosphorylation.

Employing breast cancer cell lines as positive controls which show both receptors at elevated levels CCSST only respond to higher concentrations of heregulin.

The functional impact of the expression of ERBB3 still remains to be elucidated and may be more complex than expected.