Neural and mesenchymal differentiations in Ewing's sarcoma cell lines. Morphological, immunophenotypic, molecular biological and cytogenetic evidence

Three established Ewing's sarcoma (ES) cell lines (TC106, 6647, A4573), grown both in vitro and as xenograft tumors, were analyzed. In all 3 lines and tumors, the ES characteristic reciprocal translocation (11;22), as well as the presence of the ES-associated p30/32M1C2 antigen, were documented. However, these cell lines showed discrepancies in their neural and mesenchymal differentiation. The TC106 line was characterized by expression of the neuroendocrine marker secretogranin II (SgII) which was detectable by Northern blot and by radioimmunological detection (RIA) in the culture medium of secretoneurin, a proteolytic product of SgII. In contrast, TC106 cells were immunohistochemically and…