title: Differential expression of NGF receptors in human thymic epithelial tumors.
abstract: NGF receptor (TrkA and p75NGFR) expression was investigated in human thymuses, including normal thymuses, thymic hyperplasias, thymomas and thymic carcinomas. TrkAI but not TrkAII transcripts were demonstrated by RT-PCR. In normal thymuses, immunohistochemistry revealed a restricted TrkA-immunoreactivity to epithelial and interdigitated reticular cells, while only interdigitaded reticular cells were immunoreactive for p75NGFR. Thymocytes were negative for both receptors. A switch from the normal TrkA positive-p75NGFR negative phenotype to a TrkA negative-p75NGFR positive phenotype was found in histologically aggressive epithelial cell tumors, suggesting that NGF and its receptors are potentially involved in thymus stroma organogenesis and proliferation.
authors.affiliation: Laboratoire d'Histologie-Embryologie, CHU de Bordeaux, France. Marie.Parrens@histo.u-bordeaux2.fr
authors.forename: M
authors.initials: M
authors.lastname: Parrens
authors.forename: P
authors.initials: P
authors.lastname: Dubus
authors.forename: A
authors.initials: A
authors.lastname: Groppi
authors.forename: J F
authors.initials: JF
authors.lastname: Velly
authors.forename: E
authors.initials: E
authors.lastname: Labouyrie
authors.forename: A
authors.initials: A
authors.lastname: de Mascarel
authors.forename: J P
authors.initials: JP
authors.lastname: Merlio
mesh_terms: D034961:Antigens, Nuclear; D002277:Carcinoma / Q000378:metabolism*; D006801:Humans; D006965:Hyperplasia / Q000378:metabolism; D007150:Immunohistochemistry; D009687:Nuclear Proteins / Q000096:biosynthesis; D020033:Protein Isoforms / Q000096:biosynthesis; D020917:Receptor, trkA / Q000096:biosynthesis; D017475:Receptors, Nerve Growth Factor / Q000096:biosynthesis*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013945:Thymoma / Q000378:metabolism*; D013950:Thymus Gland / Q000378:metabolism* / Q000473:pathology; D013953:Thymus Neoplasms / Q000378:metabolism*
chemical_list: D034961:Antigens, Nuclear; D009687:Nuclear Proteins; D020033:Protein Isoforms; D017475:Receptors, Nerve Growth Factor; D020917:Receptor, trkA