The carcinogenicity of human papillomavirus types reflects viral evolution

Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, US Department of Health and Human Services, Bethesda, MA, USA.
Virology (Impact Factor: 3.32). 07/2005; 337(1):76-84. DOI: 10.1016/j.virol.2005.04.002
Source: PubMed

ABSTRACT Persistent infections with carcinogenic human papillomaviruses (HPV) cause virtually all cervical cancers. Cervical HPV types (n > 40) also represent the most common sexually transmitted agents, and most infections clear in 1-2 years. The risks of persistence and neoplastic progression to cancer and its histologic precursor, cervical intraepithelial neoplasia grade 3 (CIN3), differ markedly by HPV type. To study type-specific HPV natural history, we conducted a 10,000-woman, population-based prospective study of HPV infections and CIN3/cancer in Guanacaste, Costa Rica. By studying large numbers of women, we wished to separate viral persistence from neoplastic progression. We observed a strong concordance of newly-revised HPV evolutionary groupings with the separate risks of persistence and progression to CIN3/cancer. HPV16 was uniquely likely both to persist and to cause neoplastic progression when it persisted, making it a remarkably powerful human carcinogen that merits separate clinical consideration. Specifically, 19.9% of HPV16-infected women were diagnosed with CIN3/cancer at enrollment or during the five-year follow-up. Other carcinogenic types, many related to HPV16, were not particularly persistent but could cause neoplastic progression, at lower rates than HPV16, if they did persist. Some low-risk types were persistent but, nevertheless, virtually never caused CIN3. Therefore, carcinogenicity is not strictly a function of persistence. Separately, we noted that the carcinogenic HPV types code for an E5 protein, whereas most low-risk types either lack a definable homologous E5 ORF and/or a translation start codon for E5. These results present several clear clues and research directions in our ongoing efforts to understand HPV carcinogenesis.

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Available from: Ana Cecilia Rodriguez, Sep 27, 2015
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    • "Infection with two specific types, HPV 16 and HPV 18, account for approximately 70% of cervical cancer cases worldwide, with the remainder of cases largely attributable to 14 other types (Bernard et al., 2010). Nevertheless, the great majority of infections with even carcinogenic HPV types are ultimately benign, demonstrating that HPV infection, although necessary, is not sufficient to cause of cervical cancer (Schiffman et al., 2005; Plummer et al., 2007). "
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    ABSTRACT: A major goal in infectious disease research is to identify the human and pathogenic genetic variants that explain differences in microbial pathogenesis. However, neither pathogenic strain nor human genetic variation in isolation has proven adequate to explain the heterogeneity of disease pathology. We suggest that disrupted co-evolution between a pathogen and its human host can explain variation in disease outcomes, and that genome-by-genome interactions should therefore be incorporated into genetic models of disease caused by infectious agents. Genetic epidemiological studies that fail to take both the pathogen and host into account can lead to false and misleading conclusions about disease etiology. We discuss our model in the context of three pathogens, Helicobacter pylori, Mycobacterium tuberculosis and human papillomavirus, and generalize the conditions under which it may be applicable.
    Frontiers in Genetics 08/2014; 5:290. DOI:10.3389/fgene.2014.00290
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    • "HPV types are traditionally grouped into phylogenetically-related species based on the genetic similarity of their L1 genes [50]. High-risk HPV types that cause cervical cancer fall largely, though not exclusively, within the Alphapapillomavirus 9 (alpha-9) species characterized by HPV-16 and including types -31, -33, -35, -52 and -58 and the alpha-7 species characterized by HPV-18 and including types -39, -45, -59 and -68 [51]. It is well documented that progression to SCC is greater for HPV-16 than HPV-18, but that HPV-18 is over-represented in ADC compared to SCC [52]. "
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    ABSTRACT: Data on the current burden of adenocarcinoma (ADC) and histology-specific human papillomavirus (HPV) type distribution are relevant to predict the future impact of prophylactic HPV vaccines. We estimate the proportion of ADC in invasive cervical cancer, the global number of cases of cervical ADC in 2015, the effect of cervical screening on ADC, the number of ADC cases attributable to high-risk HPV types -16, -18, -45, -31 and -33, and the potential impact of HPV vaccination using a variety of data sources including: GLOBOCAN 2008, Cancer Incidence in Five Continents (CI5) Volume IX, cervical screening data from the World Health Organization/Institut Catala d'Oncologia Information Centre on HPV and cervical cancer, and published literature. ADC represents 9.4% of all ICC although its contribution varies greatly by country and region. The global crude incidence rate of cervical ADC in 2015 is estimated at 1.6 cases per 100,000 women, and the projected worldwide incidence of ADC in 2015 is 56,805 new cases. Current detection rates for HPV DNA in cervical ADC tend to range around 80--85%; the lower HPV detection rates in cervical ADC versus squamous cell carcinoma may be due to technical artefacts or to misdiagnosis of endometrial carcinoma as cervical ADC. Published data indicate that the five most common HPV types found in cervical ADC are HPV-16 (41.6%), -18 (38.7%), -45 (7.0%), -31 (2.2%) and -33 (2.1%), together comprising 92% of all HPV positive cases. Future projections using 2015 data, assuming 100% vaccine coverage and a true HPV causal relation of 100%, suggest that vaccines providing protection against HPV-16/18 may theoretically prevent 79% of new HPV-related ADC cases (44,702 cases annually) and vaccines additionally providing cross-protection against HPV-31/33/45 may prevent 89% of new HPV-related ADC cases (50,769 cases annually). It is predicted that the currently available HPV vaccines will be highly effective in preventing HPV-related cervical ADC.
    BMC Cancer 11/2013; 13(1):553. DOI:10.1186/1471-2407-13-553 · 3.36 Impact Factor
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    • "The finding that the HPV-16/18 AS04-adjuvanted vaccine demonstrates efficacy against 6-month persistent infection with low-risk HPV types is unexpected, as the low-risk types are phylogenetically not closely related to the oncogenic types [17]. However, in the last few years, cell-mediated immune responses to HPV-6 and HPV-11 in women vaccinated with the HPV-16/18 AS04-adjuvanted vaccine have been observed. "
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    ABSTRACT: Background: Public Health England has reported a decrease of up to 20.8% in new diagnoses of external genital warts (GWs) among women aged <19 years since the national vaccination program with the human papillomavirus (HPV)-16/18 AS04-adjuvanted vaccine began in 2008. A post hoc analysis of the phase III PATRICIA (PApilloma TRIal against Cancer In young Adults) trial (NCT00122681) was performed to ascertain whether protection against low-risk HPV types was apparent. Methods: Vaccine efficacy (VE) at 48 months was assessed against 6-month persistent infection (6MPI) with low-risk HPV types in the total vaccinated cohort (TVC) and in the TVC naive (for 25 HPV types tested) populations. Results: In the TVC naive cohort, VE against 6MPI (95% confidence interval) was 34.5% (11.3 to 51.8) for HPV-6/11, 34.9% (9.1 to 53.7) for HPV-6, 30.3% (-45.0 to 67.5) for HPV-11, and 49.5% (21.0 to 68.3) for HPV-74. Conclusions: The HPV-16/18 AS04-adjuvanted vaccine appears to have moderate efficacy against persistent infections with a number of low-risk HPV types (HPV-6/11/74), which are responsible for the majority of external GWs, and recently, antibody and cell-mediated immune response to HPV-6/11 have been observed. These findings may help to explain the decrease in external GW diagnoses seen in England.
    The Journal of Infectious Diseases 11/2013; 208(9):1391-1396. DOI:10.1093/infdis/jit360 · 6.00 Impact Factor
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