Immunohistochemical analysis of cell-cycle- and apoptosis-related factors in lining epithelium of odontogenic keratocysts

We examined the immunohistochemical expressions of cell-cycle- and apoptosi s-related factors to investigate the possible role of these factors in odon togenic keratocyst (OKC). Expression of cyclin D1 and p16 protein was detec ted in the basal and parabasal cells in lining epithelium of OKCs and was f ound more frequently in basal cell nevus syndrome (BCNS)-associated OKCs th an in primary or recurrent OKCs, Positivity for p21 protein was detected in basal to superficial cells, whereas that for p27 protein was detected in p arabasal to superficial cells in lining epithelium of OKCs. DNA topoisomera se II alpha reacted with nuclei in basal and parabasal cells of the lining epithelium of OKCs, and positive cells were observed in BCNS-associated OKC s significantly more frequently than in primary or recurrent OKCs, Expressi on of Fas in suprabasal to superficial cells and expression of Fas-L in bas al and parabasal cells were detected in lining epithelium of OKCs. Immunore activity for caspase-3 was detected in basal to suprabasal or superficial c ells in lining epithelium of OKCs, Single stranded (ss)DNA-positive nuclei were detected in superficial cells in lining epithelium of OKCs. Fas was mo re broadly distributed in BCNS-associated OKCs than in primary OKCs, and ss DNA-positive cells were observed in BCNS-associated OKCs significantly more frequently than in primary or recurrent OKCs, These results suggest that B CNS-associated OKCs might be a distinguishable entity from solitary OKCs.