Association of Matrix Metalloproteinase (MMP)-2 and -9 Expression with Extra-gastrointestinal Stromal Tumor Metastasis

Matrix metalloproteinase (MMP)-2 and MMP-9 are important proteases involved in invasion and metastasisof various tumors. Extra-gastrointestinal stromal tumors (EGISTs) are rare neoplasms. This study was performedto assess MMP-2 and MMP-9 expression in EGIST tissue samples for association with clinicopathological datafrom the patients. Twenty-one surgical EGIST tissue specimens were collected for analysis of MMP-2 and MMP-9 expression using immunohistochemistry. MMP-2 and MMP-9 proteins were expressed in all of the epithelialcell types of EGISTs, whereas they were only expressed in 75% of the spindle cell type, although there was nostatistically significant difference (p>0.05). Expression of MMP-2 and MMP-9 proteins was associated with tumorsize, mitotic rate, tumor necrosis, and distant metastasis (p<0.05). MMP-2 expression was linked with MMP-9levels (p<0.05). However, there was no correlation between MMP-9 expression and age, sex, primary site, or cellmorphology in any of these 21 EGIST patients (p>0.05). Moreover, expression of MMP-2 and MMP-9 proteinsincreased with the degree of EGIST risk. This study provided evidence of an association of MMP-2 and MMP-9expression with advanced EGIST behavior.