Analysis of human papillomavirus type-16 variants in Italian women with cervical intraepithelial neoplasia and cervical cancer

J Med Virol. 2004 Sep;74(1):117-26. doi: 10.1002/jmv.20154.

Abstract

Human papillomavirus type 16 (HPV-16) classes (E, AA, As, Af1, Af2) and their variants have different geographic distribution and different degrees of association with cervical lesions. This study was designed to examine HPV-16 variants among Italian women and their prevalence in case patients (affected by invasive cervical carcinoma or cervical intraepithelial neoplasia grade 2-3 and cervical intraepithelial neoplasia grade 1), versus control subjects with normal cervical epithelium (controls). A total of 90 HPV-16 positive cervical samples from women of Italian Caucasian descent have been tested, including 36 invasive cervical carcinomas, 21 with cervical intraepithelial neoplasias grade 2-3, 17 with cervical intraepithelial neoplasia grade 1 and 16 controls. HPV-16 was detected with an E6/E7 gene-specific polymerase chain reaction, and variant HPV-16 classes and subclasses were identified by direct nucleotide sequencing of the region coding for the E6 and the E7 oncoproteins, the MY09/11-amplified highly conserved L1 region, and the long control region (LCR). Among the 90 HPV-16 samples, nine viral variants have been identified belonging to the European (Ep-T350 and E-G350) and non-European (AA and Af-1) branches. The E-G350 is the prevalent variant in all analyzed different disease stages being present in 55.5% of ICC, 52.4% of cervical intraepithelial neoplasias 2-3, 47.1% of cervical intraepithelial neoplasia grade 1, and 50.0% of control samples. The non-European variants AA and Af1, rarely detected in control samples, represent 33.3% of all HPV-16 infections in invasive cervical carcinoma (with a peak of 19.4% and 13.9%, respectively), showing a statistically significant increase in frequency in more advanced lesions (chi(2) trend = 7.2; P < 0.05). The prevalence of HPV-16 Ep-T350, however, is higher in controls (43.7%) and in of cervical intraepithelial neoplasia grade 1 (41.2%) than in cervical intraepithelial neoplasia grade 2-3 (28.6%) and in invasive cervical carcinoma (11.1%) cases strongly suggesting lack of progression for pre-neoplastic lesions associated with such variant. The increased frequency of non-European variants in invasive lesions suggests that they are more oncogenic than European variants. This could have implications for future diagnostic and therapeutic strategies.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Capsid Proteins / genetics
  • Case-Control Studies
  • Disease Progression
  • Female
  • Genes, Viral
  • Genetic Variation*
  • Genotype
  • Humans
  • Italy / epidemiology
  • Middle Aged
  • Molecular Epidemiology
  • Oncogene Proteins, Viral / genetics
  • Papillomaviridae / classification
  • Papillomaviridae / genetics*
  • Papillomaviridae / isolation & purification
  • Papillomavirus E7 Proteins
  • Papillomavirus Infections / epidemiology
  • Papillomavirus Infections / virology*
  • Phylogeny
  • Polymerase Chain Reaction
  • Repressor Proteins / genetics
  • Sequence Analysis, DNA
  • Uterine Cervical Dysplasia / epidemiology
  • Uterine Cervical Dysplasia / virology*
  • Uterine Cervical Neoplasms / epidemiology
  • Uterine Cervical Neoplasms / virology*

Substances

  • Capsid Proteins
  • E6 protein, Human papillomavirus type 16
  • Oncogene Proteins, Viral
  • Papillomavirus E7 Proteins
  • Repressor Proteins
  • oncogene protein E7, Human papillomavirus type 16
  • L1 protein, Human papillomavirus type 16