Activation of TRK genes in Ewing's sarcoma. Trk A receptor expression linked to neural differentiation.
Diagn Mol Pathol
; 6(1): 10-6, 1997 Feb.
Article
em En
| MEDLINE
| ID: mdl-9028732
ABSTRACT
Trk receptors have been identified by immunohistochemical methods in primitive neuroectodermal tumor (PNET)/Ewing's sarcoma (ES). However, the presence of different members of the Trk family of receptors in PNET/ES has not been specified. We have examined whether Trk A, B, and C receptors are specifically expressed in ES both with and without features of neural differentiation. Ten ES tumors (five primary tumors of bone and five extraosseous tumors transplanted into nude mice) were investigated for expression of Trk receptors by immunohistochemistry and reverse transcription-polymerase chain reaction. One primary ES and the five grafted ES tumors exhibited signs of neural differentiation; the remaining four primaries were undifferentiated ES. Other tumor types were analyzed as controls; they included three neuroblastomas (NB), two lymphomas, and single cases of pheochromocytoma (PHEO), schwannoma (SCHW), osteosarcoma, and carcinoma of breast, colon, and kidney. Trk receptors were detected in paraffin-embedded tumor tissue sections by means of a pan-Trk polyclonal antibody raised against the 14 carboxy-terminal residues of gp140trk, and trk A, B, and C transcripts were specifically detected by polymerase chain reaction-based amplification on cDNAs derived from tumor RNA with MuLV reverse transcriptase. Reactivity to the pan-Trk antibody was exhibited by six ES tumors, the three NBs, and the single PHEO and SCHW cases; immunoreactivity was restricted to differentiated tumors, in the case of ES. Tumor types positive for immunostaining were also distinguished by containing transcripts of TRK genes. However, the trk A, B, and C expression pattern of ES differed from that of NBs, PHEO, and SCHW. Transcripts of trk A, B, and C were detected in seven, four, and one case of ES, respectively, and in five, two, and five cases of NB, PHEO, and SCHW, respectively. Interestingly, all differentiated ES tumors contained trk A transcripts. Tumors of neuroectodermal phenotype and/or derivation were thus characterized by a distinct consensus expression pattern trk A+/B-/C+ for differentiated ES and trk A+/B-/C+ for NB-PHEO-SCHW. These results indicate that the TRK gene family is frequently activated in ES; they also suggest that Trk A receptor is a feature of ES with neural differentiation, whereas Trk B and C receptors seem to be present in undifferentiated ES.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Sarcoma de Ewing
/
Regulação Neoplásica da Expressão Gênica
/
Proteínas Proto-Oncogênicas
/
Receptores de Fator de Crescimento Neural
/
Receptores Proteína Tirosina Quinases
/
Tumores Neuroectodérmicos Primitivos
/
Neurônios
Tipo de estudo:
Prognostic_studies
Limite:
Animals
Idioma:
En
Revista:
Diagn Mol Pathol
Assunto da revista:
BIOLOGIA MOLECULAR
/
PATOLOGIA
Ano de publicação:
1997
Tipo de documento:
Article
País de afiliação:
Espanha