Soft tissue Ewing's sarcoma: Characterization in established cultures and xenografts with evidence of a neuroectodermic phenotype

Abstract

This study characterizes the histogenesis of soft tissue Ewing's sarcoma (StEs) based upon an analysis of three tumors. Long-term cultured cell lines and nude mice xenografts were established from original neoplasms or from their metastases. Histologically they revealed a small round cell pattern without signs of differentiation. Several ultrastructural features of neural type were found; the same were also seen on culture cell lines. Moreover, immunohistochemical study for neural markers revealed the presence of HNK-1, NSE, LIRC-LON 36, S-100 protein, glial fibrillary acidic protein, neurofilaments (70 kilodaltons), and chromogranin; some of these markers were present only in the transplants. Cytokeratin was also seen. The translocation t(11;22)(q24;q12) was found in all three neoplasms together with other chromosomal abnormalities. N-myc RNA gave negative results whereas c-myc RNA was expressed. Therefore it may be postulated that StEs displays neuroectodermal features somewhat similar to those seen in peripheral neuroepithelioma as well as in atypical Ewing's sarcoma of bone.

Orthopaedic Case of the Month: A 14-Year-Old Boy With a Medial Thigh Soft Tissue Mass

“…Histologically, this tumor is characterized by spherical to polygonal cells with round to oval nuclei and glycogen content [26,31,52]. The described immunohistochemistry varies, although immunoreactivity to CD99, S-100, and vimentin, with absence of cytokeratin and desmin, has been noted [9,25,30]. FISH and RT-PCR analyses reveal the fusion gene EWS-FL1 [t(11;22)(q24;q 12)] is present in greater than 80% of cases and an EWS-ETS fusion gene in most others.…”

Molecular Analysis of the 9p21 Locus and p53 Genes in Ewing Family Tumors

“…Some cases had been characterized previously by ultrastructural and immunohistochemistry (Llombart-Bosch et al, 1990). The most relevant clinical data from our cases are shown in Table 2.…”

“…EFT are specifically associated with cytogenetic rearrangements (Delattre et al, 1994), with the resultant fusion genes involving EWS gene and members of the ETS family of transcription factors, which from a clinical point of view provide a valuable diagnostic and prognostic marker (de Alava et al, 1998a(de Alava et al, , 1998bKovar, 1998;Llombart-Bosch, 1999;Llombart-Bosch et al, 1990Patiño-Garcia and Sierrasesúmaga, 1997;Pellín et al, 1994;Turc-Carel et al, 1988). EWS-ETS rearrangements are implicated in generating malignant transformation of EFT, but the presence of additional genetic alterations must be considered in their pathogenesis (Kovar, 1998;Llombart-Bosch, 1999).…”

Establishment and Characterization of a Clonal Human Extraskeletal Ewing's Sarcoma Cell Line, EES1

“…There were no significant associations between cytokeratin expression and each of the following parameters: patient age, sex, skeletal and extraskeletal primary site. Fujii et al (1989) and Llombart-Bosch et al (1990) reported positivity of their established EES cells for cytokeratin. In the present case, the primary tumor did not express keratin but the xenograft was reactive with keratin.…”

“…The extensive literature survey reveals that only ten cell lines of EES or PNET have been reported so far (Whang-Peng et al 1986;Fujii et al 1989;Homma et al 1989;Llombart-Bosch et al 1990;Hara et al 1991). Whang-Peng et al (1986) evaluated long cultured EES and the other small, round, blue-cell tumors including rhabdomyosarcoma, Ewing's sarcoma of bone, and mesenchymal chondrosarcoma.…”