Immunohistochemical study of bcl-2 protein, Ki-67 antigen and p53 protein in epithelium of glandular odontogenic cysts and dentigerous cysts.

The aim of the present study was the evaluation of the immunohistochemical expression of the apoptosis-inhibiting protein bcl-2, the cell-cycle-related antigen Ki-67 and the p53 protein, which is involved both in cell cycle and apoptosis regulation, in the lining epithelium of glandular odontogenic cysts of the jaws. Formalin-fixed and paraffin-embedded tissue sections of three glandular odontogenic cysts and six dentigerous cysts were immunostained with a standard avidin-biotin peroxidase procedure, after microwave antigen retrieval. The glandular odontogenic cysts showed immunoreactivity for bcl-2 protein in the basal and suprabasal layers, while staining in dentigerous cysts was basal or focal. Most mucous cells and superficial cuboidal cells were negative. The percentage of Ki-67- or p53-positive cells was lower in glandular odontogenic cysts compared with dentigerous cysts. The findings suggest that the biological behavior of glandular odontogenic cysts may be associated with deregulation of cell death in the lining epithelium, while cell proliferation and p53 status do not seem to play a significant role.