Differential Diagnosis of Gingival Hyperplasia Based on IFN-γ-stimulated Gene Expression Using RT-PCR ( epulus / gingival squamous cell carcinoma / RT-PCR / IFN-γ / apoptosis / proliferation )

Epulus is a benign gingival tumour of unknown aetiopathogenesis. Classification is inconsis- tent, and standard management strategies are lacking. Epuli are generally believed to be inflammatory rather than neoplastic lesions. The literature does not present any molecular analysis of the tumour characteristics. The purpose of the present study was to compare benign (epulus) and malignant (cancer) gingival hyper- plasias with regard to the activity of the genes of apop- tosis, proliferation, and inflammation using RT-PCR. The investigation involved 70 patients with epuli and 15 patients with gingival squamous cell carcinoma. Each subject had specimens collected from the tumour, tissue margin (incision line), and healthy tissue. Molecular investigations by RT-PCR were used to eval- uate expression levels of the genes associated with apoptosis (Bcl-2, Bax, Bcl-2/Bax), proliferation (H3 histone), and inflammatory processes (IFN-γ, IFNγ-R1, IFN-γR2, IFN-γR1/IFN-γR2). Correlations have been disclosed between apoptosis and proliferation genes expression in giant cell epuli and high-differentiated gingival squamous cell carcinoma. In RT-PCR molecu- lar analysis, giant cell epulus shows characteristics of a neoplastic lesion, while other epulus types seem to be inflammatory tumours.