Immunoexpression of Extracellular Matrix Metalloproteinase Inducer (EMMPRIN) and Angiogenic Index in Odontogenic Cysts

Extracellular matrix remodeling and angiogenesis are important events in the evolution of cystic and neoplastic lesions. This study aimed to assess and compare the differential expression of extracellular matrix metalloproteinase inducer (EMMPRIN) and angiogenic index in radicular cysts (RCs), dentigerous cysts (DCs), and odontogenic keratocysts (OKCs). Twenty RCs, 20 DCs, and 20 OKCs were evaluated by immunohistochemistry. The expression of EMMPRIN was evaluated in the epithelial component and in endothelial cells of vessels in the fibrous capsule of the lesions. The angiogenic index was determined by microvessel count (MVC) using anti-CD105 immunoexpression. Immunoexpression of EMMPRIN was observed in most RCs (95%) and in all DCs and OKCs. Compared with RCs and DCs, OKCs revealed lower immunopositivity for EMMPRIN in the epithelial component ( P <0.001). In endothelial cells, EMMPRIN expression was higher in OKCs than in RCs ( P =0.010) and DCs ( P =0.007). RCs had the highest angiogenic index, with a statistically significant difference compared with OKCs ( P =0.018). A positive correlation was observed between MVC and immunoexpression of EMMPRIN in endothelial cells of vessels in RCs ( r =0.654; P =0.002). The results suggest an important role for EMMPRIN in the development of RCs, DCs, and OKCs. The higher expression of this metalloproteinase inducer in endothelial cells of vessels in the fibrous capsule of OKCs could be related to the aggressive biological behavior of these lesions. In RCs, EMMPRIN seems to act as a proangiogenic factor.