Detection of Survivin and COX-2 in Thyroid Carcinoma: Anaplastic Carcinoma Shows Overexpression of Nuclear Survivin and Low COX-2 Expression

BACKGROUND: Overexpression of survivin, a member of the inhibitors of apoptosis protein, has been reported in various carcinomas, and its interaction with cyclooxygenase 2 (COX-2) results in accelerated tumor progression. The purpose of this study is to investigate the immunohistochemical expression of survivin and COX-2 in benign and malignant thyroid tissues and to define its association with pathologic and clinical features. METHODS: We examined expression of survivin and COX-2 by immunohistochemistry in 334 benign and malignant thyroid tissues and evaluated their clinical significance. RESULTS: Expression of survivin showed an increase along the spectrum of thyroid carcinoma progression; rarely positive in adenomatous goiter, moderately positive in papillary carcinoma, and strongly positive in anaplastic carcinoma (AC). Papillary microcarcinoma revealed the highest COX-2 positivity and AC demonstrated the lowest positivity among thyroid cancers. Node negative carcinomas showed higher COX-2 expression than node positive tumors. Survivin expression did not correlate with COX-2. CONCLUSIONS: Our findings suggest that survivin overexpression may be related to the pathogenesis of AC and can be a predictor of disease progression. COX-2 may be involved in the early phase of thyroid carcinoma.