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

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 hereg…