Matrix metalloproteinase-2 expression correlates with morphological and immunohistochemical epithelial characteristics in synovial sarcoma.
OBJECTIVE
Synovial sarcoma is a unique mesenchymal tumour characterized by the presence of epithelial differentiation, although the mechanism involved in the epithelial morphology is still unclear. The aim of this study was to evaluate the function of matrix metalloproteinase-2 (MMP-2) in synovial sarcoma, in order to assess whether MMP-2 expression plays an important role in epithelial differentiation, or whether it contributes to a poor clinical outcome.


RESULTS
Immunohistochemical stainings for MMP-2, cytokeratins (CKs) 7, 8, 18 and 19, and E-cadherin were performed for 58 (44 monophasic and 14 biphasic) cases of synovial sarcoma, and we compared the expression of these proteins with the histological and clinical findings. MMP-2 and E-cadherin expression was observed in 43 cases (74.1%) and in 18 cases (31.0%), respectively. Expression of these proteins was preferentially observed in the glandular components of biphasic tumours or the epithelioid areas of monophasic tumours. Statistically significant correlations were recognized between MMP-2 expression and E-cadherin expression of biphasic subtype. Moreover, there were statistically significant correlations between monophasic tumours with epithelioid areas and MMP-2 expression or E-cadherin expression. MMP-2 expression was correlated with epithelial differentiation as assessed by CK immunoreactivity. The expression of MMP-2 did not affect the overall survival rate in synovial sarcoma.


CONCLUSIONS
MMP-2 expression seemed to have an important role to play in the epithelial differentiation of tumour cells in synovial sarcoma, through remodelling of the extracellular matrix and by changing the cytoskeletal interaction between the extracellular matrix and tumour cells.
Saito
T
T
Department of Anatomic Pathology, Kyushu University, Graduate School of Medical Sciences, Fukuoka, Japan.
Oda
Y
Y
Sakamoto
A
A
Tamiya
S
S
Iwamoto
Y
Y
Tsuneyoshi
M
M
D015820:Cadherins / Q000032:analysis; D004848:Epithelium / Q000737:chemistry / Q000201:enzymology / Q000473:pathology; D006801:Humans; D007150:Immunohistochemistry; D007633:Keratins / Q000032:analysis; D020778:Matrix Metalloproteinase 2 / Q000096:biosynthesis*; D013584:Sarcoma, Synovial / Q000201:enzymology / Q000378:metabolism / Q000473:pathology*
D015820:Cadherins; D007633:Keratins; D020778:Matrix Metalloproteinase 2