Human papillomavirus in malignant neoplasms of different localizations

Abstract

Introduction. High-risk human papillomaviruses (HPVs) which include dozens of genotypes (16, 18, 45, etc.) are detected in some malignant tumors. Aim. To determine the viral load, genotypes and DNA status for HPVs in HPV-positive tumour tissue samples taken from patients with malignant neoplasms of different localisation. Materials and methods. A total of 61 HPV-positive tumor tissue samples from patients with oropharyngeal, anal cancer and malignant neoplasms of the female genital organs were studied. Identification, genotyping, viral load and detection of physical status of HPV-DNA were carried out by real-time PCR using commercially available domestic test kits. Results. All samples showed the presence of HPV genotype 16: in 86.9% (53/61) as a monogenotype and in the rest as combinations with 18, 31, 35, 39, 45. A high HPV viral load was detected in 60.7% of cases, mainly in anal and cervical cancers. A partially integrated (‘mixed’) viral DNA was detected in 97.4% (37/38) of samples with high viral load, while a fully integrated viral DNA was detected in 83.3% (5/6) of samples with low viral load (p=0.00003). Conclusion. DNA of HPV genotype 16 partially or fully integrated into the human genome was detected in all HPV-positive tumour tissue samples of malignant neoplasms of different localizations. The fully integrated form was detected in samples with low viral load in both early and late stages of cancer.