Detailed Characteristics of Tonsillar Tumors with Extrachromosomal or Integrated Form of Human Papillomavirus

0559716 - ÚMG 2023 RIV CH eng J - Článek v odborném periodiku
Pokryvkova, B. - Salaková, M. - Šmahelová, J. - Vojtěchová, Z. - Novosadová, Vendula - Tachezy, R.
Detailed Characteristics of Tonsillar Tumors with Extrachromosomal or Integrated Form of Human Papillomavirus.
Viruses. Roč. 12, č. 1 (2020), č. článku 42. E-ISSN 1999-4915
Grant CEP: GA MŠMT(CZ) LQ1604; GA MŠMT(CZ) EF16_019/0000785
Institucionální podpora: RVO:68378050
Klíčová slova: human papillomavirus * E2 binding sites * methylation * genome status
Obor OECD: Virology
Impakt faktor: 5.048, rok: 2020
Způsob publikování: Open access
https://www.mdpi.com/1999-4915/12/1/42

The human papillomavirus (HPV) integration, the critical step in viral carcinogenesis, most frequently occurs in the E2 gene, which results in its inactivation and in an increase of E6/E7 transcription. However, in a substantial number of tumors, the virus is present in an extrachromosomal form. For those tumors, the transformation mechanisms are not fully elucidated. Here we evaluated the possible mechanism of inactivating the E2 without interruption of the gene, methylation or mutation of the E2 binding sites (E2BSs) in HPV16-positive tonsillar tumors by next-generation and Sanger sequencing. Viral genome status was analyzed by the amplification of papillomavirus oncogene transcripts assay (APOT) and mRNA mapping, and expression of viral oncogenes was performed by qPCR. The methylation of E2BSs was significantly higher in tumors with an integrated, in comparison to extrachromosomal, form of the viral genome. No mutations were detected in the E2BSs. The viral oncogenes were equally expressed in samples with an integrated and extrachromosomal form of the virus. Only the nucleotide variants were identified in the E2 gene. No proposed mechanism of E2 inactivation was confirmed in tonsillar tumors with an extrachromosomal form of the HPV genome. The expression of E6/E7 genes seems to be sufficient to initiate and maintain the carcinogenic process
Trvalý link: https://hdl.handle.net/11104/0332925