Overexpression of p53 as a possible prognostic factor in human thyroid carcinoma.
A total of 110 cases of thyroid carcinomas were examined immunohistochemically to evaluate the overexpression of mutant forms of p53 protein in the light of their relationship with their histological subtypes. A polyclonal antibody, CM-1, was applied to the routine formalin-fixed, paraffin-embedded tissues for this survey. Overall, immunohistochemically detected p53 expression confined to the nucleus was identified in 22.7% of the thyroid carcinomas. A significant difference in the positivity of p53 among histological subtypes was noted; the positivity was 11.1% of the cases in well-differentiated papillary carcinoma, 14.3% in well-differentiated follicular carcinoma, 40.9% in poorly differentiated carcinoma, and 63.6% in undifferentiated carcinoma. No immunohistochemical positivity was found in adjacent non-neoplastic tissues or in benign lesions, including follicular adenoma, adenomatous goiter, and chronic thyroiditis. These results suggest that overexpression of p53 is not a responsible factor for the oncogenesis itself, but rather that it plays a crucial role in aggressive subtypes of thyroid carcinomas. Additionally, the distinct entity of poorly differentiated carcinoma, previously categorized in the well-differentiated carcinoma under the name of papillary or follicular carcinoma, was statistically confirmed.
Dobashi
Y
Y
Department of Pathology, Faculty of Medicine, University of Tokyo, Japan.
Sakamoto
A
A
Sugimura
H
H
Mernyei
M
M
Mori
M
M
Oyama
T
T
Machinami
R
R
D002277:Carcinoma / Q000378:metabolism* / Q000473:pathology; D006801:Humans; D007150:Immunohistochemistry / Q000379:methods; D011379:Prognosis; D013194:Staining and Labeling; D013964:Thyroid Neoplasms / Q000378:metabolism* / Q000473:pathology; D016159:Tumor Suppressor Protein p53 / Q000378:metabolism*
D016159:Tumor Suppressor Protein p53