Korean J Pathol.  2006 Feb;40(1):60-65.

Expressions of Id-1 and Id-2 in Hyperplastic Thyroid Tissue and Thyroid Carcinoma

• Kim YA
• Park YJ
• Park DJ
• Park SH
• Kim JE

Abstract

BACKGROUND: Id proteins are a family of helix-loop-helix proteins and are regarded to be negative regulators of cell differentiation. In general, Id-1 and Id-2 expressions are upregulated during tumor development and progression in a variety of neoplasms, and these expressions may be associated with aggressive tumor behavior. However, little is known about the roles of Id-1 and Id-2 in thyroid neoplasms.
METHODS
The expressions of Id-1 and Id-2 were assessed immunohistochemically in 310 normal, hyperplastic, and neoplastic thyroid tissues using tissue microarrays.
RESULTS
Normal thyroid tissues rarely expressed Id-1 or Id-2. Moreover, whilst Id-1 expression was more elevated in malignant thyroid tissue than in hyperplastic thyroid tissue, Id-2 expression was more variable. No significant differences were observed between histologic subtypes of thyroid carcinomas with respect to Id-1 or Id-2 expression. Follicular adenomas showed higher expressions of Id-1 and Id-2 than thyroid carcinomas. No significant association was found between clinicopathological parameters and Id-1 expression, though Id-2 expression was significantly reduced in metastatic, stage IV tumors.
CONCLUSION
The expressions of Id-1 and Id-2 were elevated in hyperplastic and neoplastic thyroid tissues. However, neither appears suitable as a marker of malignancy or an aggressive phenotype, although Id-2 expression in advanced thyroid carcinomas may reflect a favorable prognosis.

Keyword

Inhibitor of differentiation protein 1; Inhibitor of differentiation protein 2; Thyroid gland; Carcinoma, papillary; Adenocarcinoma, follicular; Adenoma

MeSH Terms

Adenocarcinoma, Follicular
Adenoma
Carcinoma, Papillary
Cell Differentiation
Humans
Inhibitor of Differentiation Protein 1
Inhibitor of Differentiation Protein 2
Phenotype
Prognosis
Thyroid Gland*
Thyroid Neoplasms*
Inhibitor of Differentiation Protein 1
Inhibitor of Differentiation Protein 2