Genotyping and Phylogenetic Analysis of Human Papillomaviruses in Formalin Fixed Paraffin Embedded Sections from Cervical Lesions in Duhok-Iraq

Abstract

Objective: Human papillomavirus (HPV) has been identified as an important causative factor in cervical cancer development. Cervical cancer is the fourth most prevalent malignant tumor among women globally. The purpose of this study was to investigate the prevalence and genotyping sequences of HPV in formalin-fixed paraffin-embedded (FFPE) cervical tissue using conventional polymerase chain reaction (PCR), and HPV-DNA sequencing. Material and Methods: Retrospective cross-sectional study. Forty (FFPE) blocks with different cervical lesions were taken; patients’ ages ranged from 24 to 65 years. Detection and sequencing of HPV DNA were done by conventional PCR (L1 gene), which was achieved by universal PCR primers (MY09/11 oligonucleotides). Then sequencing and phylogenetic tree was constructed. Results: Nine samples were found positive and detected by conventional PCR, they were identified in CIN1 and SCC at 7.5% (n=3) for each, 5.0% (n=2) KA, and 2.5% (n=1) in CIN3 cases, after sequencing were submitted to GenBank and accession numbers were obtained. The phylogenetic tree was constructed and the aligned sequences showed high homology with the nucleotide sequence of the references from the Genbank database. HPV 11, 16, 18, 22, 33, 52, and 58 were found to have little nucleotide heterogeneity and thus no amino acid heterogeneity. Conclusion: Sequencing and phylogenetic analysis of circulating HPV types in Duhok provides very essential data about nucleotides and amino acid heterogeneity, to reveal genetic diversity with strains included in the vaccines that have not been introduced to Iraq yet.

Iniciadores utilizados en la identificación de virus de papiloma humano por PCR: una revisión

“…Los genotipos de alto riesgo corresponden a VPH 16,18,31,33,35,39,45,51,52,56,58,59, 66, 68, 73 y 82 (2, 3) y los de bajo riesgo incluyen a los genotipos VPH 6,11,40,42,43,44,54,61,70,72, 81 y CP6108 (3,4). No obstante, acorde a diferentes estudios, las variantes VPH 16 y VPH 18 son los genotipos más prevalentes, con altos porcentajes en las lesiones precancerosas y cáncer de cuello uterino (CCU) considerado como el tercer motivo de cáncer más frecuente en mujeres en todo el mundo, sobre todo en los países en vías de desarrollo (5,6), por esta razón es el principal motivo de investigación epidemiológica y del desarrollo de vacunas.…”