Increased expression of matrix metalloproteinase-2: a diagnostic marker but not prognostic marker of papillary thyroid carcinoma.
BACKGROUND
Matrix metalloproteinases are proteolytic enzymes that degrade extracellular matrix components. Numerous studies have demonstrated that individual MMPs play a crucial role in tumor invasion and metastasis.


OBJECTIVE
To examine the expression of MMPs and their inhibitor TIMP-2 in neoplastic and normal thyroid tissues.


METHODS
We examined 33 cases of thyroid tumor (papillary, follicular and medullary carcinoma, follicular adenoma and multinodular goiter). MMP protein content and activity were measured by enzyme-linked immunosorbent assay and gel zymography. Immunohistochemistry was also performed.


RESULTS
The thyroid tissues examined secreted MMP-2 and 9 as well as TIMP-2, but only MMP-2 was significantly higher in papillary carcinoma cases compared to the adjacent normal tissue or to the other tumor entities. Increased MMP-2 immunohistochemical staining was demonstrated in the neoplastic papillary epithelial component. No significant difference was seen between papillary carcinomas with lymph node metastases and those without.


CONCLUSIONS
Increased MMP-2 expression may be useful as a diagnostic marker to differentiate papillary carcinoma from other thyroid neoplasms, but it cannot serve as a useful prognostic marker.
Korem
Sigal
S
Endocrine Research Unit, Carmel Medical Center and Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa, Israel.
Kraiem
Zaki
Z
Shiloni
Eitan
E
Yehezkel
Oved
O
Sadeh
Orit
O
Resnick
Murray B
MB
D014408:Biomarkers, Tumor / Q000378:metabolism; D002291:Carcinoma, Papillary / Q000175:diagnosis* / Q000201:enzymology / Q000473:pathology; D003937:Diagnosis, Differential; D004797:Enzyme-Linked Immunosorbent Assay; D006801:Humans; D020778:Matrix Metalloproteinase 2 / Q000378:metabolism*; D061965:Matrix Metalloproteinase Inhibitors; D011379:Prognosis; D011480:Protease Inhibitors / Q000494:pharmacology; D013964:Thyroid Neoplasms / Q000145:classification / Q000175:diagnosis* / Q000201:enzymology / Q000473:pathology; D019716:Tissue Inhibitor of Metalloproteinase-2 / Q000494:pharmacology; D014407:Tumor Cells, Cultured
D014408:Biomarkers, Tumor; D061965:Matrix Metalloproteinase Inhibitors; D011480:Protease Inhibitors; D019716:Tissue Inhibitor of Metalloproteinase-2; D020778:Matrix Metalloproteinase 2