Evaluation of p53, PCNA, Ki-67, MDM2 and AgNOR in oral peripheral and central giant cell lesions

OBJECTIVES: Peripheral giant cell lesion (PGCL) and central giant cell lesi on (CGCL) of the jaws have a distinct clinical behaviour, Whether such biol ogical differences are supported by a distinct pattern of proliferation mar kers or cell cycle associated proteins expression is not known, Therefore t he purpose of the present study was to compare the immunohistochemical expr ession of p53, MDM2, Ki-67, PCNA and the histochemical expression of argyro philic nuclear organiser region (AgNOR) on PGCL and CGCL of the jaws. MATERIALS AND METHODS: Paraffin wax blocks of 14 cases of PGCL and IZ cases of CGCL were retrieved. A biotin-streptavidin amplified system was used fo r identification of the antigens, The AgNOR number was also evaluated, RESULTS: Ki-67 immunoreactivity was greater in the mononuclear cells of PGC L compared to CGCL, PCNA and AgNOR staining were similar in PGCL and CGCL, Prominent MDM2 immunoreactivy was observed in all tissues investigated, By contrast, there was no p53 immunoreactivity. CONCLUSIONS: Although CGCL present a more aggressive clinical behaviour, it has a decreased proliferative activity compared to PGCL. Finally, p53, MDM 2, PCNA, Ki-67 immunohistochemical expression and AgNOR histochemical expre ssion do not reflect their distinct biological behaviour.