[ immunohistochemical comparative evaluation of CK13 and CK18 expression in odontogenic cysts and ameloblastoma]

ABSTRACT

Evaluating cytokeratin contents of odontogenic cysts and tumors can be one of the important aspects in comparative study of these lesions. The aim of this study was to evaluate expression of CK13 and CK18 in odontogenic cysts and ameloblastomas. In this study, radicular cysts [20 cases], dentigerous cysts [20 cases], OKC [20 cases], unicystic ameloblastoma [20 cases] and solid ameloblastoma [20 cases] were evaluated. Then, 3-4 micro m sections were prepared and stained with immuhistochemical procedure [avidin- biotin method. The obtained data by microscopic consideration was analyzed with statistical tests such as Chi-square, Mann-Whitney, Wilcoxon [p<0.05]. All of the odontogenic cysts and cystic parts of unicystic ameloblastoma expressed CK13 in the upper layers [middle and superficial] more than the deeper ones [basal and parabasal]. In ameloblastomas, CK 13 expression in stellate reticulum and acanthomatose component was more than preameloblasts. Expression of CK 18 in the upper layers [middle and superficial] was more than deeper layers [basal and parabasal] in radicular and dentigerous cysts. Results of immunoreactivity with CK18 in OKC was negative in 100% of cases. In addition, ameloblastomas [unicystic and solid] did have not significant differences in expression of CK13 and CK18. CK13 did not show any differences between these lesions but significant difference in CK18 expression at all 4 layers of the epithelium in odontogenic cysts and ameloblastomas may indicate the different nature of these lesions and probably confirms this suggestion that unicystic ameloblastoma is initiated as a neoplasm essentially, no from neoplastic change of an odontogenic cyst, in particular dentigerous cyst. The same CK 13 and CK18 expression pattern in unicystic and solid ameloblastomas reveals the same biomolecular nature despite different gross and clinical features