c-myc copy number gain is a powerful prognosticator of disease outcome in cervical dysplasia

Abstract

Cervical carcinoma develops from preneoplasia by a multistep process. Although most low-grade dysplastic lesions will regress without intervention and even high-grade changes exhibit a substantial rate of regression, a small percentage of dysplasia will progress over time. Thus, indicators are needed to estimate the biological risk and to help avoid overtreatment in women who desire to preserve fertility. In addition to the classical biomarkers, PCR-ELISA-determined HPV genotype and immunohistochemically assessed p16^INK4a and Ki-67 expression, cells with integrated HPV and copy number gain of TERC and c-myc were quantified in a panel of 104 benign, intraepithelial neoplastic (CIN I, II, III) and cancerous lesions using fluorescence in situ hybridization. Optimal cut-off values were calculated; Kaplan-Meier curves and a Cox proportional hazard regression model were used to evaluate prognostic signatures. The assay reliably identified HPV integration, TERC and c-myc copy number gain as determined by comparisons with established biomarkers. All biomarker levels increased with the progression of the disease. However, only c-myc copy number gain independently prognosticated a low probability of dysplastic regression. Our results suggest that c-myc plays a key role in the process of dysplastic transformation and might thus be exploited for treatment and follow-up decision-making of cervical dysplasia.