Abstract | OBJECTIVE: STUDY DESIGN: Twenty follicular thyroid neoplasms were classified as adenomas (11) or minimally invasive follicular carcinomas (9) according to current pathological criteria. Protein expression was evaluated to identify differences between benign and malignant tumors that could be used as an adjunct to histopathological analysis. METHODS:
Paraffin-embedded tissue sections containing tumor and adjacent nonneoplastic parenchyma were analyzed by immunohistochemistry for the expression of TbetaR type II (TbetaR-II) and Smad2, Smad4, Smad6, and Smad7. Expression of each protein in the tumor was compared with that of the corresponding adjacent nonneoplastic thyroid parenchyma. RESULTS: TbetaR-II expression was lost in 78% of the carcinomas. In the remaining 22%, TbetaR-II was preserved but Smad2 expression was lost. In all conventional adenomas, however, TbetaR-II expression was maintained. Furthermore, all tumors with normal expression of all proteins were adenomas. CONCLUSIONS: Downregulation of TbetaR-II is a consistent abnormality in follicular carcinomas and can be used to differentiate minimally invasive carcinomas from adenomas. Also, downregulation of Smad proteins is another mechanism by which carcinomas can become independent from TGF-beta-mediated growth inhibition.
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Authors | J West, T Munoz-Antonia, J G Johnson, D Klotch, C A Muro-Cacho |
Journal | The Laryngoscope
(Laryngoscope)
Vol. 110
Issue 8
Pg. 1323-7
(Aug 2000)
ISSN: 0023-852X [Print] United States |
PMID | 10942134
(Publication Type: Journal Article)
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Chemical References |
- Biomarkers, Tumor
- DNA-Binding Proteins
- Receptors, Transforming Growth Factor beta
- SMAD2 protein, human
- SMAD4 protein, human
- SMAD6 protein, human
- Smad2 Protein
- Smad4 Protein
- Smad6 Protein
- Trans-Activators
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Topics |
- Adenocarcinoma, Follicular
(metabolism, pathology)
- Adenoma
(metabolism)
- Biomarkers, Tumor
(metabolism)
- DNA-Binding Proteins
(metabolism)
- Humans
- Immunohistochemistry
- Neoplasm Invasiveness
- Receptors, Transforming Growth Factor beta
(metabolism)
- Signal Transduction
- Smad2 Protein
- Smad4 Protein
- Smad6 Protein
- Thyroid Neoplasms
(metabolism, pathology)
- Trans-Activators
(metabolism)
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