Significance of p53, cyclin D1 and c-myc Expressions in Thyroid Tumors

Li, Zhuhu; Jeon, Ho Jong; Lee, Mi Ja

Abstract

BACKGROUND: The G1/S phase proteins of the cell cycle play critical roles in tumorigenesis and tumor progression. Our aim was to investigate the significance of p53, cyclin D1 and c-myc expressions in thyroid tumors.
METHODS
The expressions of these proteins were examined in 217 cases of thyroid tumors and tissues using immunohistochemistry. The results were correlated with lymph node metastasis.
RESULTS
p53 expression was seen in 75.5, 47.5, 66.7, and 50% of papillary carcinomas (PC), follicular carcinomas (FC), undifferentiated carcinomas (UC) and follicular adenomas (FA), respectively. There was a significant difference between these expressions in these tumors and the results in nodular hyperplasia (NH) and normal tissues. Cyclin D1 expression was noted in 80.0, 68.4, 66.7, 61.1 and 79.5% of PC, FC, UC, FA and NH, respectively. c-myc expression was seen in 80.0, 94.2, 66.7, 66.7 and 52.3% of PC, FC, UC, FA and NH, respectively. There was a significant association between the expressions in these tumors and the results in normal tissues. The expressions of p53, cyclin D1 and c-myc were not correlated with lymph node metastasis.
CONCLUSIONS
These findings suggest the expressions of p53, cyclin D1 and c-myc may act in the early stage, and participates in tumorigenesis and promoting cell growth.