title: TTF-1 expression in nephroblastoma.
abstract: The unexpected observation of nuclear immunoreactivity for thyroid transcription factor-1 (TTF-1) associated with an apparent lack of nuclear immunoreactivity for Wilms tumor-1 protein (WT1) in the pulmonary metastasis of a morphologically typical case of nephroblastoma affecting a 6.5-year-old male prompted us to examine the expression of these 2 markers (and CD56) in a series of 48 nephroblastomas, 5 adult metanephric adenomas, and 1 pediatric cystic nephroma. TTF-1 was found to be positive in 8 of 48 (16.6%) nephroblastomas and negative in all 5 metanephric adenomas. WT1 was positive in 43 of 48 (89.6%) nephroblastomas and 4 of 5 (80.0%) metanephric adenomas. CD56 was positive in 45 of 47 cases that were so tested (95.74%), but negative in all metanephric adenomas. The single cystic nephroma was TTF-1-negative, WT1-negative, and CD56-positive. The finding of TTF-1 expression in one sixth of nephroblastomas constitutes a potential source of misdiagnosis. The biologic significance of this surprising finding is unclear. It may reflect the embryonal nature of these tumors and may conceivably result-directly or indirectly-in interference with the transcriptional control of target genes and other molecular events in the pathway leading to the development of nephroblastoma.
authors.affiliation: Department of Pathology, IRCCS-Casa Sollievo della Sofferenza Hospital, San Giovanni Rotondo (FG), Italy. bismi@libero.it
authors.forename: Michele
authors.initials: M
authors.lastname: Bisceglia
authors.forename: Moira
authors.initials: M
authors.lastname: Ragazzi
authors.forename: Carlos A
authors.initials: CA
authors.lastname: Galliani
authors.forename: Gaetano
authors.initials: G
authors.lastname: Lastilla
authors.forename: Juan
authors.initials: J
authors.lastname: Rosai
mesh_terms: D000328:Adult; D014408:Biomarkers, Tumor / Q000032:analysis*; D019002:CD56 Antigen / Q000096:biosynthesis; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D007223:Infant; D007680:Kidney Neoplasms / Q000378:metabolism* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D009687:Nuclear Proteins / Q000096:biosynthesis*; D012189:Retrospective Studies; D000074482:Thyroid Nuclear Factor 1; D014157:Transcription Factors / Q000096:biosynthesis*; D025721:WT1 Proteins / Q000096:biosynthesis; D009396:Wilms Tumor / Q000378:metabolism* / Q000473:pathology
chemical_list: D014408:Biomarkers, Tumor; D019002:CD56 Antigen; C000614412:NKX2-1 protein, human; D009687:Nuclear Proteins; D000074482:Thyroid Nuclear Factor 1; D014157:Transcription Factors; D025721:WT1 Proteins