Analysis of cyclin D1 and retinoblastoma protein immunoreactivity in follicular thyroid tumors.
Protein products of cyclin D1 and retinoblastoma (Rb) genes play crucial roles in regulation of G1/S transition in the cell cycle. In this study we analyzed, using immunohistochemical methods, the expression of cyclin D1 and Rb proteins in material from medical archives (12 cases of follicular thyroid carcinoma, 57 cases of follicular adenoma and 17 nodular goiter cases). A positive nuclear reaction for cyclin D1 was observed in 83.3% (10/12) of the follicular carcinomas, in 96.5% (55/57) of the follicular adenomas and in 23.5% (4/17) of nodular goiters. Overexpression of cyclin Dl (more than 50% of positively staining cells) was noted in 25% (3/12) of the follicular carcinomas and in 22.8% (13/57) of the follicular adenomas. No overexpression of cyclin D1 was noted among nodular goiters. The number of carcinoma cases with cyclin D1 overexpression did not differ statistically in any significant way from the follicular adenoma group (p = 1.000). A positive nuclear reaction for Rb protein was noted in 100% of the follicular carcinomas (12/12), in 96.5% of the follicular adenomas (55/57) and in 47.1% of the cases (8/17) of nodular goiter. Rb protein overexpression (more than 50% of positively staining cells) was found in 83.3% (10/12) of the follicular carcinomas, in 68.4% (39/57) of the follicular adenomas and in 11.8% (2/17) of the nodular goiters. The number of cases with Rb protein overexpression in the follicular carcinoma group did not differ significantly from that in the follicular adenoma group (p = 0.486). A positive correlation was found in the groups studied between the expressions of Rb protein and cyclin D1. However, the correlation was statistically significant only in the nodular goiter group (Rs = 0.567; p = 0.018). In the follicular carcinoma group, that correlation was borderline (Rp = 0.437; p = 0.072) and, in the follicular adenoma group, it was statistically insignificant (Rs = 0.217; p = 0.105). Our results confirm the existence of mutual regulation mechanisms of Rb and cyclin D1 protein expressions, which are observed in cells from various carcinomas.
Ferenc
Tomasz
T
Department of Biology and Genetics, Medical University, Lódź.
Lewiński
Andrzej
A
Lange
Dariusz
D
Niewiadomska
Hanna
H
Sygut
Jacek
J
Sporny
Stanisław
S
Jarzab
Barbara
B
Satacińska-Los
Elzbieta
E
Kulig
Andrzej
A
Włoch
Jan
J
D018263:Adenocarcinoma, Follicular / Q000378:metabolism* / Q000473:pathology; D000236:Adenoma / Q000378:metabolism* / Q000473:pathology; D014408:Biomarkers, Tumor / Q000378:metabolism; D019938:Cyclin D1 / Q000378:metabolism*; D006044:Goiter, Nodular / Q000378:metabolism / Q000473:pathology; D006801:Humans; D016160:Retinoblastoma Protein / Q000378:metabolism*; D013964:Thyroid Neoplasms / Q000378:metabolism* / Q000473:pathology
D014408:Biomarkers, Tumor; D016160:Retinoblastoma Protein; D019938:Cyclin D1