IMMUNOHISTOCHEMICAL DISTRIBUTION OF THE SIBLINGS IN AMELOBLASTOMA AND ODONTOGENIC KERATOCYST

Abstract

Objective Ameloblastomas are benign but aggressive neoplasms of the jaw. The odontogenic keratocysts (OKC) are aggressive jaw cysts of odontogenic origin. A recent WHO classification designated OKC as a neoplasm but a current edition re-designated it as a cyst. The small integrin-binding ligand n-linked glycoproteins (SIBLINGs) are a family of molecules that some epithelial neoplasms use in furthering their progression. Members of the SIBLING family are bone sialoprotein (BSP), dentin matrix protein1 (DMP1), dentin sialophosphoprotein (DSPP), matrix extracellular phosphoglycoprotein (MEPE), and osteopontin (OPN). The objective of this study was to compare the expression of the SIBLINGs in ameloblastomas and odontogenic keratocysts. Findings Using immunohistochemistry, with appropriate controls, 49 cases of ameloblastomas and 35 cases of OKCs were screened for the expression of all five SIBLINGs in a retrospective study on archived paraffin sections. Immunoreactivity was scored as positive if > 10% of tumor/cyst cells stained for a SIBLING and negative if Conclusion While all members of the SIBLINGs are expressed in ameloblastomas and OKCs, DSPP expression in OKCs is significantly higher than in ameloblsatomas, whereas, MEPE expression in OKCs is considerably lower than in ameloblastomas. The differences in the expression of DSPP and MEPE between ameloblastomas and OKCs may indicate differences in the degree of aggressive behaviors.