Analysis of human papillomavirus and Epstein-Barr virus infection and aberrant death-associated protein kinase methylation in high-grade squamous intraepithelial lesions

This study was conducted to investigate the presence of Epstein-Barr virus (EBV) and human papillomavirus (HPV) and the promoter methylation status of the death-associated protein kinase (DAPK) gene in high-grade intraepithelial lesions. Viral infection was analyzed using polymerase chain reaction (PCR), and promoter methylation status was evaluated using chemical modification by sodium bisulfite followed by PCR. A total of 24 samples were studied. HPV was detected in 16.6%, EBV in 16.6%, and HPV/EBV coinfection in 16.6%. No virus infection was detected in 50% of the samples studied. DAPK promoter methylation was observed in 29.2% of the analyzed samples. There was no significant correlation between DAPK methylation and viral infection. DAPK methylation was detected in 28% of HPV-positive lesions, in 28% of HPV- and EBV-positive lesions, and in 44% (3/7) of the samples without viral infection. There was no observed methylation in samples with isolated EBV infection. In DAPK unmethylated samples, HPV infection was found in 12%, EBV infection in 23%, HPV/EBV coinfection in 12%, and an absence of HPV and EBV infection in 53%. The promoter methylation of the DAPK gene is an important event during carcinogenesis and may have potential clinical application as a marker for the progression and prognosis of cancer.