High prevalence of epidermodysplasia verruciformis-associated human papillomavirus DNA in actinic keratoses of the immunocompetent population

E6/E7 from Beta-2-HPVs 122, 38b, and 107 possess transforming properties in a fibroblast model in vitro

Beta-2 Human papillomaviruses 38b, 107, and 122 have been frequently found in cervical cancer samples in western Mexico. Because their E6/E7 genes functions are not fully elucidated, we deepen into their transformation capabilities. To achieve this goal, primary human fibroblasts (FB) were transduced with E6/E7 genotype-specific viral particles. Additionally, E6/E7 from HPVs 16 and 18 were included as controls. All E6/E7-cell models increased their lifespan; however, it is important to highlight that FB-E6/E7-122 showed growth as accelerated as FB-E6/E7-16 and 18. Furthermore, both FB-E6/E7-38b and 122 exhibited abilities to migrate, and FB-E6/E7-122 presented high invasive capacity. On the other hand, ΔNp73 expression was found in all cell models, except for FB-pLVX (empty-vector). Finally, RNAseq found differentially expressed genes enriched in signaling pathways related to cell cycle, epithelial-mesenchymal transition, and cancer, among others. This study shows for the first time, the great transformative potential that genotypes of the Beta-2 also possess, especially HPV122. These Beta-2 HPVs can modulate some of the genes that are well known to be regulated by Alpha-HPVs, however, they also possess alternative strategies to modulate diverse signaling pathways. These data support the idea that Beta-2 HPVs should play an important role in co-infections with Alpha-HPV during carcinogenesis.

Comparative analysis of different PCR-based strategies for HPV detection and genotyping from cervical samples

BACKGROUND

Human papillomavirus (HPV) is the main cause of cervical cancer. Polymerase chain reaction (PCR)-based techniques are associated with accurate results with respect to HPV detection and genotyping, being able to identify viral DNA at low levels. However, differences in primer design influence their sensibility and specificity, depending on the HPV type assessed.

OBJECTIVE

The aim of the study was to comparatively evaluate the effectiveness of three different PCR-based strategies for HPV detection and genotyping from cervical samples.

STUDY DESIGN

The procedures were based on different primer design strategies, using MY09/MY11, EntroA, and type specific multiplex PCR primers.

RESULTS

Out of 411 samples of cervical scrapings, 45 (10.9%), 50 (12.2%), and 117 (28.5%) were positive for MY09/MY11, EntroA, and multiplex PCR, respectively. For MY09/MY11 positive samples, 36 were negative for EntroA and 23 for multiplex PCR. For EntroA positive samples, 40 were negative for MY09/MY11 and 26 for multiplex PCR. For multiplex PCR positive samples, 96 were negative for MY09/MY11 and 94 for EntroA. MY09/MY11 identified 12 different HPV types, EntroA detected eight types and multiplex PCR detected 11 HPV types. EntroA primers were able to detect HPV in more samples than MY09/MY11, while multiplex PCR, despite the limited targeted HPV types, presented higher sensibility than the other methods.

CONCLUSIONS

The three methods presented different advantages and disadvantages, and the present study reinforces the need to use more than one molecular strategy for HPV detection and genotyping, and the development of novel methods which could overcome the limitations of the existing tests.

A Systematic Review and Meta-Analysis: Evaluation of the β-Human Papillomavirus in Immunosuppressed Individuals with Cutaneous Squamous Cell Carcinoma

Background

Some types of beta-human papillomavirus (β-HPV) may be one of the probable causes of squamous cell carcinoma (SCC) in transplant recipients. β-HPVs are linked to SCC in the literature with small number of subjects.

Aim

Herein, the first meta-analysis was carried out on the association between β-HPVs and cutaneous SCC in immunosuppressed patients.

Methods

A systematic search was carried out in the PubMed and Scopus databases up to December 2018. The odds ratio (OR) were calculated by RevMan 5.3 software and the event rate (ER) by Comprehensive Meta-Analysis 2.0 software with a 95% confidence interval (CI).

Results

A total of 1250 records were identified through the two databases, but at last eleven studies were included in the meta-analysis that they were published from 1989 to 2018. The results showed a significantly high prevalence of β-HPVs in cutaneous SCC patients (ER = 69.1%; 95%CI: 58.7%, 77.8%). In addition, the prevalence of overall β-HPVs and β-HPVs of 5, 8, 9, 17, 49, 75, and 76 in immunosuppressed cutaneous SCC patients was significantly higher compared with controls.

Conclusions

The findings of the present meta-analysis support the hypothesis that β-HPV may play a role in cutaneous SCC development in immunosuppressed individuals.

E2 protein is the major determinant of specificity at the human papillomavirus origin of replication

The replication of human papillomavirus (HPV) genomes requires E1 and E2 proteins as the viral trans-factors and the replication origin, located in the URR, as a cis-element. The minimal requirements for an HPV replication origin vary among different virus types but always include one or more binding sites for the E2 protein. The requirements for an E1 binding site seem to vary among different HPV genera, with alpha-HPV11 and -18 minimal origins able to replicate without E1 binding site in contrast to beta-HPV8. In the present article, we analysed the sequence requirements for the beta-HPV5 minimal origin of replication. We show that the HPV5 URR is able to replicate in U2OS cells without the sequence proposed as an E1 binding site, albeit at lower levels than wt URR, given that three E2 binding sites are intact and both viral replication proteins are present. The lack of an absolute requirement of the E1 binding site for the origin of replication of HPV5 led us to analyse whether the viral E1 and E2 proteins from other HPV types are competent to support replication from this origin. Surprisingly, the E1 and E2 proteins from beta-HPV types support replication from the origin in contrast to proteins from alpha-HPV types 11, -16, or -18. Furthermore, the replication proteins E1 and E2 of these alpha-HPV types are unable to support the replication of HPV5 URR, even if the E1 binding site is intact. In light of these results, we performed a detailed analysis of the ability of different combinations of E1 and E2 proteins from various alpha- and beta-HPV types to support the replication of URR sequences from the respective HPV types in the U2OS cell line.

Mastomys Species as Model Systems for Infectious Diseases

Replacements of animal models by advanced in vitro systems in biomedical research, despite exceptions, are currently still not satisfactory in reproducing the whole complexity of pathophysiological mechanisms that finally lead to disease. Therefore, preclinical models are additionally required to reflect analogous in vivo situations as found in humans. Despite proven limitations of both approaches, only a combined experimental arrangement guarantees generalizability of results and their transfer to the clinics. Although the laboratory mouse still stands as a paradigm for many scientific discoveries and breakthroughs, it is mandatory to broaden our view by also using nontraditional animal models. The present review will first reflect the value of experimental systems in life science and subsequently describes the preclinical rodent model Mastomys coucha that-although still not well known in the scientific community-has a long history in research of parasites, bacteria, papillomaviruses and cancer. Using Mastomys, we could recently show for the first time that cutaneous papillomaviruses-in conjunction with UV as an environmental risk factor-induce squamous cell carcinomas of the skin via a "hit-and-run" mechanism. Moreover, Mastomys coucha was also used as a proof-of-principle model for the successful vaccination against non-melanoma skin cancer even under immunosuppressive conditions.

The molecular biology and HPV drug responsiveness of cynomolgus macaque papillomaviruses support their use in the development of a relevant in vivo model for antiviral drug testing

Due to the extreme tissue and species restriction of the papillomaviruses (PVs), there is a great need for animal models that accurately mimic PV infection in humans for testing therapeutic strategies against human papillomaviruses (HPVs). In this study, we present data that demonstrate that in terms of gene expression during initial viral DNA amplification, Macaca fascicularis PV (MfPV) types 5 and 8 appear to be similar to mucosal oncogenic HPVs, while MfPV1 (isolated from skin) resembles most high-risk cutaneous beta HPVs (HPV5). Similarities were also observed in replication properties during the initial amplification phase of the MfPV genomes. We demonstrate that high-risk mucosal HPV-specific inhibitors target the transient replication of the MfPV8 genomes, which indicates that similar pathways are used by the high-risk HPVs and MfPVs during their genome replication. Taking all into account, we propose that Macaca fascicularis may serve as a highly relevant model for preclinical tests designed to evaluate therapeutic strategies against HPV-associated lesions.

High prevalence of Gammapapillomaviruses (Gamma-PVs) in pre-malignant cutaneous lesions of immunocompetent individuals using a new broad-spectrum primer system, and identification of HPV210, a novel Gamma-PV type

Genus Gammapapillomavirus (Gamma-PV) is the most diverse and largest clade within the Papillomaviridae family. A novel set of degenerate primers targeting the E1 gene was designed and further used in combination with the well-known CUT PCR assay to assess HPV prevalence and genus distribution in a variety of cutaneous samples from 448 immunocompetent individuals. General HPV, Gamma-PV and mixed infections prevalence were significantly higher in actinic keratosis with respect to benign and malignant neoplasms, respectively (p = 0.0047, p = 0.0172, p = 0.00001). Gamma-PVs were significantly more common in actinic keratosis biopsies than Beta- and Alpha-PVs (p = 0.002). The full-length genome sequence of a novel putative Gamma-PV type was amplified by 'hanging droplet' long-range PCR and cloned. The novel virus, designated HPV210, clustered within species Gamma-12. This study provides an additional tool enabling detection of HPV infections in skin and adds new insights about possible early roles of Gamma-PVs in the development of cutaneous malignant lesions.

High-risk mucosal HPV types associated with squamous cell carcinoma on the nose tip in an immunocompetent young man

The oncogenic role of high-risk HPV in anogenital, head and neck, and cervical cancer is well recognized, but not in skin cancer in the general population. Some authors have demonstrated their appearance mainly on the hands and feet, particularly in the area of the nail bed, which could be due to contamination with HPV types from anogenital regions. Here, we describe a case of genital HPV associated with SCC on the nose tip in an immunocompetent young man, which was confirmed by histopathological findings and in situ hybridization. The importance of this report is to highlight the potential role of HPV in the etiology of skin cancer in an immunocompetent individual.

Generation of a novel next-generation sequencing-based method for the isolation of new human papillomavirus types

With the advent of new molecular tools, the discovery of new papillomaviruses (PVs) has accelerated during the past decade, enabling the expansion of knowledge about the viral populations that inhabit the human body. Human PVs (HPVs) are etiologically linked to benign or malignant lesions of the skin and mucosa. The detection of HPV types can vary widely, depending mainly on the methodology and the quality of the biological sample. Next-generation sequencing is one of the most powerful tools, enabling the discovery of novel viruses in a wide range of biological material. Here, we report a novel protocol for the detection of known and unknown HPV types in human skin and oral gargle samples using improved PCR protocols combined with next-generation sequencing. We identified 105 putative new PV types in addition to 296 known types, thus providing important information about the viral distribution in the oral cavity and skin.

Cutaneous human papillomavirus genotypes in different kinds of skin lesions in Argentina

Cutaneous human papillomaviruses (HPVs) comprise a large and highly heterogeneous virus group. Some of the cutaneous HPVs of the genus Beta have been suggested as a co-factor in the development of non-melanoma skin cancer (NMSC). The aim of this study was to determine cutaneous HPV prevalence and type-specific distribution in different kinds of skin lesions from Argentine patients visiting Dermatology Departments of three hospitals from Buenos Aires. A cross-sectional analysis was performed. HPV DNA was analyzed in (i) 3 patients with Epidermodysplasia verruciformis (EV) harboring benign lesions (BL) (n = 1) and squamous cell carcinoma (SCC) (n = 4); (ii) 240 non-EV patients harboring: (a) BL (n = 38), (b) Actinic Keratosis (AK) (n = 83), (c) SCC (n = 74), and (d) basal cell carcinoma (BCC) (n = 96). Detection and genotyping of 35 cutaneous HPV DNA was carried out by BGC-PCR and GP5+/6 + PCR followed by reverse line blot assay. In EV patients, Beta types were found in all lesions (5/5), including the potentially high-risk HPV types 5 and 8, mostly in multiple infections. In non-EV patients, cutaneous types were found in 50.0% of BL, 43.4% of AK, 31.1% of SCC, and 16.7% of BCC. Beta HPVs were the most frequently found in all lesions, being present in all AK and SCC cases that were positive for HPV. No type-specific correlation with lesion severity was found. In our series, a wide spectrum of cutaneous HPV types was detected in different skin lesions. A possible role for these HPVs in skin carcinogenesis deserves further study. J. Med. Virol. 89:352-357, 2017. © 2016 Wiley Periodicals, Inc.

Human papillomavirus infection and p16 expression in the immunocompetent patients with extragenital/extraungual Bowen's disease

BACKGROUND

The role of human papillomaviruses (HPV) in the development of squamous cell carcinoma (SCC) has been established for anogenital lesions but still remains controversial for carcinomas in other sites. The aim of this study was to determine the α-HPV and β-HPV prevalence and their association with p16 expression, sun exposure, and clinicopathological findings in patients with Bowen's disease (BD).

METHODS

One hundred sixty nine skin biopsy specimens from 157 immunocompetent patients with extragenital/extraungual BD were examined for HPV status and p16 expression. The presence of koilocyte-like changes, solar elastosis and papillomatosis was recorded for each specimen.

RESULTS

BD was diagnosed more often in potentially sun-exposed sites with prevalence 73.6 % and a remarkable predilection for the head and neck region. High risk α-HPV or β-HPV were detected in 34.7 % of lesions and β-HPV infections dominated over α-HPV. Higher prevalence of koilocyte-like changes and papillomatosis was found in HPV-positive specimens but it was not statistically significant. The expression of p16 was detected in 79.8 % of lesions and displayed no correlation with the HPV status. HPV-positivity tended to be detected more often in sun-protected sites. Dual infections by α-HPV/β-HPV genera and mixed α-HPV infections were not detected, while 37.5 % of β-HPV positive specimens were infected by two or more β-HPV genotypes. HPV 9 was significantly associated with mixed β-HPV infections.

CONCLUSIONS

HPV may play an etiological role at least in some SCC in situ arising in extragenital sites. Sunprotected sites may be more dependent on HPV-mediated co-carcinogenesis than sun exposed areas. The presence of the p16-expression, papillomatosis or koilocyte-like change is not a reliable marker of HPV infection in SCC in situ.

The EVER genes - the genetic etiology of carcinogenesis in epidermodysplasia verruciformis and a possible role in non-epidermodysplasia verruciformis patients

In recent years, the two adjacent novel EVER1 and EVER2 genes have been identified, whose mutations are responsible for the development of epidermodysplasia verruciformis (EV). Epidermodysplasia verruciformis is a rare, autosomal recessive genodermatosis associated with increased risk of skin carcinoma. Up to now 7 mutations in the EVER1 gene and 5 mutations in the EVER2 gene have been identified only in EV. It was also determined that the EVER genes belong to a novel gene family, the transmembrane channel-like (TMC) family, and are responsible for properly functioning zinc homeostasis. These observations have given new insights into EV pathogenesis.

Downregulation of Toll-Like Receptor 9 Expression by Beta Human Papillomavirus 38 and Implications for Cell Cycle Control

Innate immunity is the first line of host defense against infections. Many oncogenic viruses can deregulate several immune-related pathways to guarantee the persistence of the infection. Here, we show that the cutaneous human papillomavirus 38 (HPV38) E6 and E7 oncoproteins suppress the expression of the double-stranded DNA sensor Toll-like receptor 9 (TLR9) in human foreskin keratinocytes (HFK), a key mediator of the antiviral innate immune host response. In particular, HPV38 E7 induces TLR9 mRNA downregulation by promoting accumulation of ΔNp73α, an antagonist of p53 and p73. Inhibition of ΔNp73α expression by antisense oligonucleotide in HPV38 E6/E7 HFK strongly rescues mRNA levels of TLR9, highlighting a key role of ΔNp73α in this event. Chromatin immunoprecipitation experiments showed that ΔNp73α is part of a negative transcriptional regulatory complex with IκB kinase beta (IKKβ) that binds to a NF-κB responsive element within the TLR9 promoter. In addition, the Polycomb protein enhancer of zeste homolog 2 (EZH2), responsible for gene expression silencing, is also recruited into the complex, leading to histone 3 trimethylation at lysine 27 (H3K27me3) in the same region of the TLR9 promoter. Ectopic expression of TLR9 in HPV38 E6/E7 cells resulted in an accumulation of the cell cycle inhibitors p21(WAF1) and p27(Kip1), decreased CDK2-associated kinase activity, and inhibition of cellular proliferation. In summary, our data show that HPV38, similarly to other viruses with well-known oncogenic activity, can downregulate TLR9 expression. In addition, they highlight a new role for TLR9 in cell cycle regulation.

IMPORTANCE

The mucosal high-risk HPV types have been clearly associated with human carcinogenesis. Emerging lines of evidence suggest the involvement of certain cutaneous HPV types in development of skin squamous cell carcinoma, although this association is still under debate. Oncogenic viruses have evolved different strategies to hijack the host immune system in order to guarantee the persistence of the infection. Their capability to evade the immune system is as important as their ability to promote cellular transformation. Therefore, understanding the viral mechanisms involved in viral persistence is a valid tool to evaluate their potential role in human carcinogenesis. Here, we show that E6 and E7 oncoproteins from the cutaneous HPV38 downregulate the expression of the double-stranded DNA sensor TLR9 of innate immunity. We also present evidence that the HPV38-mediated downregulation of TLR9 expression, in addition to its potential impact on the innate immune response, is linked to cell cycle deregulation.

Human Beta-papillomavirus infection and keratinocyte carcinomas

Although the role of oncogenic human Alpha-papillomaviruses (HPVs) in the development of mucosal carcinomas at different body sites (eg cervix, anus, oropharynx) is fully recognized, a role for HPV in keratinocyte carcinomas (KCs; basal and squamous cell carcinomas) of the skin is not yet clear. KCs are the most common cancers in Caucasians, with the major risk factor being ultraviolet (UV) light exposure. A possible role for Beta-HPV types (BetaPV) in the development of KC was suggested several decades ago, supported by a number of epidemiological studies. Our current review summarizes the recent molecular and histopathological evidence in support of a causal association between BetaPV and the development of KC, and outlines the suspected synergistic effect of viral gene expression with UV radiation and immune suppression. Further insights into the molecular pathways and protein interactions used by BetaPV and the host cell is likely to extend our understanding of the role of BetaPV in KC.

Possible association between actinic keratosis and the rs7208422 (c.917A→T, p.N306l) polymorphism of the EVER2 gene in patients without epidermodysplasia verruciformis

BACKGROUND

Mutations of the EVER1 and EVER2 genes cause epidermodysplasia verruciformis (EV), a genodermatosis associated with squamous cell carcinoma (SCC). Recently, it has been found that the rs7208422 (c.917A→T, p.N306l) polymorphism in the EVER2 gene is related to an increased risk of SCC in patients with conditions other than EV. We hypothesized that this polymorphism might be also associated with actinic keratoses (AK).

AIM

To determine whether the rs7208422 polymorphism of the EVER2 gene is associated with AK in non-EV patients.

METHODS

We genotyped rs7208422 in 65 patients with AK and 274 controls, using reverse transcription PCR.

RESULTS

We detected a trend towards an association between AK and the TT genotype of rs7208422; the frequency of this genotype was 38.5% in patients with AK and 26.3% in controls (OR  =  1.75, P  <  0.06 for recessive model of inheritance). We also found an association between rs7208422 TT and both the age at which AK appeared and the extent of the AK. This variant was more frequent in patients who had AK onset before the age of 70 years compared with those whose age of onset was above 70 years (OR = 3.14, P = 0.03 for the recessive model; OR = 2.05, P = 0.04 for allelic comparison) and more frequent in AK involving > 3 body areas (OR = 3.14, P = 0.03 for the recessive model; OR = 2.34, P = 0.01 for allelic comparison). These associations remained significant in a multivariate regression analysis, showing that both parameters were independently associated with the TT genotype (P = 0.031).

CONCLUSIONS

This study indicates a potential role of the rs7208422 (c.917A→T, P.N306l) polymorphism of the EVER2 gene in AK.

Case-control study of genus-beta human papillomaviruses in plucked eyebrow hairs and cutaneous squamous cell carcinoma

Cutaneous human papillomaviruses (HPV) have been reported in cutaneous squamous cell carcinoma (SCC). We conducted a clinic-based case-control study to investigate the association between genus-beta HPV DNA in eyebrow hairs (EBH) and SCC. EBH from 168 SCC cases and 290 controls were genotyped for genus-beta HPV DNA. SCC tumors from a subset of cases (n = 142) were also genotyped. Viral load was determined in a subset of specimens positive for a single HPV type. Associations with SCC were estimated by odds ratios (OR) and 95% confidence intervals (CI) adjusted for age and sex using logistic regression. Statistical tests were two-sided. EBH DNA prevalence was greater in cases (87%) than controls (73%) (p < 0.05), and the association with SCC increased with the number of HPV types present, (≥ 4 types vs. HPV-negative: OR = 2.02, 95% CI = 1.07-3.80; p(trend) = 0.02). Type-specific associations were observed between SCC and DNA in EBH for HPV23 (OR = 1.90, 95% CI = 1.10-3.30) and HPV38 (OR = 1.84, 95% CI = 1.04-3.24). Additionally, when compared with the controls, the DNA prevalence in EBH was significantly higher among cases for 11 of the 25 genus-beta types tested, when accounting for DNA for the same HPV type in the tumor (ORs = 3.44-76.50). Compared to controls, the mean viral DNA load in EBH among the selected cases was greater for HPV5, HPV8 and HPV24, but lower for HPV38. SCC cases were more likely than controls to have HPV DNA+ EBH for single and multiple HPV types, providing additional support for the potential role of genus-beta HPV infections in SCC development.

Mapping of betapapillomavirus human papillomavirus 5 transcription and characterization of viral-genome replication function

Betapapillomavirus replication and transcription have not been studied in detail because of a lack of suitable cellular systems supporting human papillomavirus (HPV) genome replication. We have recently shown that the human osteosarcoma cell line U2OS provides a useful environment for the genome replication of many different HPVs, including the betapapillomaviruses HPV5 and HPV8. Using mutational analysis and complementation assay, we demonstrated herein that the viral early proteins E1 and E2 are viral transfactors that are necessary and sufficient for HPV5 genome replication. We also identified four HPV5 early promoter regions with transcription start sites (TSSs) at nucleotides (nt) 184/191, 460, 840, and 1254, respectively, and the HPV late promoter with a TSS at nt 7640. In addition, we mapped the HPV5 early polyadenylation cleavage sites via 3' rapid amplification of cDNA ends (3'RACE) to nt 4457 and 4475. In total, 14 different viral mRNA species, originating from the HPV5 genome, were mapped in U2OS cells during transient and stable replication. The main splicing donor and acceptor sites identified herein are consistent with the data previously obtained in HPV5-positive skin lesions. In addition, we identified novel E8 open reading frame (ORF)-containing transcripts (E8^E1C and E8^E2C) expressed from the HPV5 genome. Similar to several other papillomaviruses, the product of the E8^E2C mRNA acts as a repressor of viral genome replication.

Oncoprotein E7 from beta human papillomavirus 38 induces formation of an inhibitory complex for a subset of p53-regulated promoters

Our previous studies on cutaneous beta human papillomavirus 38 (HPV38) E6 and E7 oncoproteins highlighted a novel activity of IκB kinase beta (IKKβ) in the nucleus of human keratinocytes, where it phosphorylates and stabilizes ΔNp73α, an antagonist of p53/p73 functions. Here, we further characterize the role of the IKKβ nuclear form. We show that IKKβ nuclear translocation and ΔNp73α accumulation are mediated mainly by HPV38 E7 oncoprotein. Chromatin immunoprecipitation (ChIP)/Re-ChIP experiments showed that ΔNp73α and IKKβ are part, together with two epigenetic enzymes DNA methyltransferase 1 (DNMT1) and the enhancer of zeste homolog 2 (EZH2), of a transcriptional regulatory complex that inhibits the expression of some p53-regulated genes, such as PIG3. Recruitment to the PIG3 promoter of EZH2 and DNMT1 resulted in trimethylation of histone 3 on lysine 27 and in DNA methylation, respectively, both events associated with gene expression silencing. Decreases in the intracellular levels of HPV38 E7 or ΔNp73α strongly affected the recruitment of the inhibitory transcriptional complex to the PIG3 promoter, with consequent restoration of p53-regulated gene expression. Finally, the ΔNp73α/IKKβ/DNMT1/EZH2 complex appears to bind a subset of p53-regulated promoters. In fact, the complex is efficiently recruited to several promoters of genes encoding proteins involved in DNA repair and apoptosis, whereas it does not influence the expression of the prosurvival factor Survivin. In summary, our data show that HPV38 via E7 protein promotes the formation of a multiprotein complex that negatively regulates the expression of several p53-regulated genes.

Analysis of the genetic diversity and phylogenetic relationships of putative human papillomavirus types

More than 170 human papillomavirus (HPV) types have been completely sequenced, curated and divided into five genera: Alphapapillomavirus, Betapapillomavirus, Gammapapillomavirus, Mupapillomavirus and Nupapillomavirus. With the application of PCR methods, hundreds of putative novel HPV types have been identified as PCR amplicons in mucosa and skin. However, at present there are no studies reporting a systematic search of the currently known L1 amplicons and their phylogenetic relationships. This survey revealed the existence of at least 202 different putative HPV types that are pending for full-genome characterization: five alphapapillomaviruses, 37 betapapillomaviruses, 159 gammapapillomaviruses and one mupapillomavirus. All potential viruses of the genera Alphapapillomavirus and Betapapillomavirus were grouped in the defined species, while 59 putative gammapapillomaviruses types were segregated in 21 unidentified putative species. These data highlight the need for progress in the identification of additional taxa of the family Papillomaviridae in order to elucidate the diversity, evolution and medical implications of these viruses.

Eyebrow hairs from actinic keratosis patients harbor the highest number of cutaneous human papillomaviruses

BACKGROUND

Cutaneous human papillomavirus (HPV) infections seem to be associated with the onset of actinic keratosis (AK). This study compares the presence of cutaneous HPV types in eyebrow hairs to those in tissues of normal skin and skin lesions of 75 immunocompetent AK patients.

METHODS

Biopsies from AK lesions, normal skin and plucked eyebrow hairs were collected from each patient. DNA from these specimens was tested for the presence of 28 cutaneous HPV (betaPV and gammaPV) by a PCR based method.

RESULTS

The highest number of HPV prevalence was detected in 84% of the eyebrow hairs (63/75, median 6 types) compared to 47% of AK lesions (35/75, median 3 types) (p< 0.001) and 37% of normal skin (28/75, median 4 types) (p< 0.001), respectively. A total of 228 HPV infections were found in eyebrow hairs compared to only 92 HPV infections in AK and 69 in normal skin. In all three specimens HPV20, HPV23 and/or HPV37 were the most prevalent types. The highest number of multiple types of HPV positive specimens was found in 76% of the eyebrow hairs compared to 60% in AK and 57% in normal skin. The concordance of at least one HPV type in virus positive specimens was 81% (three specimens) and 88-93% of all three combinations with two specimens.

CONCLUSIONS

Thus, eyebrow hairs revealed the highest number of cutaneous HPV infections, are easy to collect and are an appropriate screening tool in order to identify a possible association of HPV and AK.

Apoptosis and in situ and invasive squamous cell carcinoma in sun-exposed sites

In vitro evidence indicates that the E6 protein of human papillomavirus (HPV) targets Bak, a proapoptotic protein, expression of which is enhanced in epidermal keratinocytes in response to ultraviolet B radiation. Given this, our aim was to ascertain Bak expression and prevalence of beta-HPV (β-HPV) in cutaneous squamous cell carcinoma (SCC) from sun-exposed sites to test our hypothesis that the virus plays a role in the neoplastic process by suppressing UV-induced apoptosis. This retrospective study included 30 cases of cutaneous SCC and 30 cases of SCC in situ (SCCIS) from sun-exposed sites. Immunohistochemical staining for Bak protein was performed on all, and β-HPV subtyping on 10 randomly selected cases from each group, using a broad-spectrum polymerase chain reaction-reverse hybridization assay. A semiquantitative scoring system for immunohistochemical expression of Bak was used based on the percentage positivity of the cells. Of cases studied, 30 of 30 (100%) of SCCIS and SCC (mean score 4.2 and 4.6, respectively, demonstrated immunopositivity, albeit to varying degrees, with Bak. Of the selected cases studied with reverse hybridization assay, 7 of 10 (70%) of SCCIS and 3 of 10 (30%) of SCC had β-HPV with HPV-5 being the most common subtype detected. Enhanced Bak immunoexpression confirms the presence of UV-induced apoptosis in both in situ as well as invasive epithelial malignancies, although the lack of differences in expression of Bak between both groups studied suggests that its relevance in disease progression is minimal. Expression of Bak in 100% of HPV-containing lesions from sun-exposed sites suggests that the virus does not abrogate UV-induced apoptosis.

Structural basis for hijacking of cellular LxxLL motifs by papillomavirus E6 oncoproteins

E6 viral oncoproteins are key players in epithelial tumors induced by papillomaviruses in vertebrates, including cervical cancer in humans. E6 proteins target many host proteins by specifically interacting with acidic LxxLL motifs. We solved the crystal structures of bovine (BPV1) and human (HPV16) papillomavirus E6 proteins bound to LxxLL peptides from the focal adhesion protein paxillin and the ubiquitin ligase E6AP, respectively. In both E6 proteins, two zinc domains and a linker helix form a basic-hydrophobic pocket, which captures helical LxxLL motifs in a way compatible with other interaction modes. Mutational inactivation of the LxxLL binding pocket disrupts the oncogenic activities of both E6 proteins. This work reveals the structural basis of both the multifunctionality and the oncogenicity of E6 proteins.

Case-control study of cutaneous human papillomavirus infection in Basal cell carcinoma of the skin

Genus-β human papillomavirus (HPV) DNA has been detected in basal cell carcinoma (BCC) tumors, but most epidemiologic studies have not observed associations between genus-β HPV seropositivity and BCC. A clinic-based case-control study was conducted to investigate cutaneous HPV infection in BCC. BCC cases (n=224) were recruited from a dermatology clinic, and controls (n=300) were patients who were screened negative for skin cancer. Antibodies against cutaneous HPV types in genera α, β, γ, mu, and nu were measured, and tumors from a subset of BCC cases (n=195) were tested for HPV DNA. Overall associations were observed between BCC and seropositivity for HPV types in genus-α (odds ratio (OR)=1.61; 95% confidence interval (CI)=1.11-2.35), γ (OR=1.78; 95% CI=1.22-2.60), and mu (OR=1.56; 95% CI=1.06-2.30). BCC cases with β-HPV DNA in their tumors were more likely to be β-HPV seropositive than controls (OR=1.76; 95% CI=1.03-3.01), with type-specific associations observed for HPV8 and HPV23, whereas no association was observed between β-HPV seropositivity and β-HPV DNA-negative BCC. No concordance between seropositivity and tumor DNA status was observed for HPV types in genera α and γ. In conclusion, the combined serology and tumor DNA results suggest that β HPV types may have a role in BCC. Additional studies of BCC that assess HPV types in multiple genera are needed.

A cross-sectional analysis of lower genital tract intraepithelial neoplasia in immune-compromised women with an abnormal Pap

OBJECTIVES

Persistent human papillomavirus (HPV) infections can cause intraepithelial neoplasia of the lower genital tract. Immune-compromised women have higher rates for all lower genital tract intraepithelial neoplasia. We wish to study the distribution of genital intraepithelial neoplasia in women with and without an immune system.

METHODS

The study consisted of 343 women with an abnormal genital lesion or cervical cytology who were referred to a gynecologic oncologist. All patients underwent vulva, vaginal, cervical and anal colposcopy. Any lesion detected was biopsied. Demographic and medical data were collected. The Chi-square test was used to determine the relationship between immunosuppression status and various variables, including sites of intraepithelial neoplasia.

RESULTS

Immune-compromised women (N = 33) are more likely than immune-competent women (N = 310) to have intraepithelial neoplasia of the vulva (p < 0.05) and vagina (p < 0.05), but not more likely to have intraepithelial neoplasia of the anus or cervix. Immune-compromised women are more likely than immune-competent women to have multifocal intraepithelial neoplasia (p < 0.001). In addition, immune-compromised women are more likely to have higher grade disease of the vulva and vagina (p < 0.05), and no more likely to have higher grade disease on the cervix or anus than immune-competent women.

CONCLUSION

Women with conditions suppressing the immune system are at higher risk for HPV-related disease outside of the cervix and for worse HPV-related diseases than immune-competent women. This study highlights the need for vigilant evaluation of the complete lower genital tract in women with immune-compromised systems.

Cutaneous squamous cell carcinoma and human papillomavirus: is there an association?

BACKGROUND

The role of human papillomavirus (HPV) in the induction and maintenance of cervical, anogenital, and some oropharyngeal carcinomas is well recognized, but its role in cutaneous squamous cell carcinoma (SCC) remains to be elucidated. HPV is thought to act as a possible cocarcinogen in the development of SCC.

OBJECTIVE

To review the literature assessing the correlation between and possible causation of HPV and cutaneous SCC in immunocompetent and immunocompromised populations.

METHODS

We reviewed HPV sampling and detection methods, epidemiologic studies examining HPV carriage in immunocompetent and immunosuppressed individuals, and evidence asserting an association between HPV and cutaneous SCC.

RESULTS

Although an abundant body of evidence points toward a link between HPV and cutaneous SCC, many studies indicate otherwise. Recent studies have focused on viral activity in addition to DNA presence.

CONCLUSION

The possibility exists that HPV may play a role in the induction but not maintenance of cutaneous SCC.

Case-control study of cutaneous human papillomaviruses in squamous cell carcinoma of the skin

BACKGROUND

Cutaneous human papillomavirus (HPV) infection may be a risk factor for squamous cell carcinoma (SCC) of the skin.

METHODS

To investigate the association between cutaneous HPV and SCC, a case-control study was conducted, including 173 SCC cases from a university dermatology clinic and 300 controls that screened negative for skin cancer. Serum antibodies against cutaneous HPV types in genera alpha, beta, gamma, mu, and nu were measured. Tumor tissue from 159 SCC cases was tested for the presence of DNA for genus-beta HPV types. Using logistic regression ORs and 95% confidence intervals (CI) were estimated for the associations between SCC and cutaneous HPV infection, adjusting for age and sex. The Bonferroni method was used to account for multiple comparisons.

RESULTS

SCC was positively associated with seropositivity to any genus-beta HPV type (OR, 1.93; 95% CI, 1.23-3.02), particularly with types in species-1 (OR, 1.86; 95% CI, 1.22-2.85). Type-specific associations with SCC were observed for HPV 8 (OR, 1.80; 95% CI, 1.14-2.84), 17 (OR, 1.59; 95% CI, 1.02-2.49) and HPV 10 from genus-alpha (OR, 2.24; 95% CI, 1.04-4.85). None of the type-specific associations remained statistically significant after correction for multiple comparisons. When DNA-positive SCC cases were compared with controls, strong serologic associations were observed for HPVs 5 (OR, 3.48; 95% CI, 1.27-9.59), 17 (OR, 3.36; 95% CI, 1.29-8.72), and 24 (OR, 3.79; 95% CI, 1.24-11.5).

CONCLUSION

Genus-beta HPV infections were associated with SCC in our study population.

IMPACT

Identifying the role of cutaneous HPV infection in SCC may lead to improved characterization of high-risk individuals and the development of novel prevention strategies.

Human papillomavirus type 8 E6 oncoprotein inhibits transcription of the PDZ protein syntenin-2

The E6 proteins from high-risk alpha human papillomavirus (HPV) types (e.g., HPV16) are characterized by the presence of a PDZ-binding motif through which they interact with a number of cellular PDZ domain-containing substrates and cooperate in their degradation. The ability of these E6 proteins to bind to PDZ domain proteins correlates with the oncogenic potential of the virus. The E6 proteins of oncogenic HPV from the genus Betapapillomavirus (betaPV, e.g., HPV8) do not encode a PDZ-binding motif. We found that the PDZ domain protein syntenin-2 is transcriptionally downregulated in primary human epidermal keratinocytes (PHEK) by HPV8 E6. The mRNA levels of the known HPV16 E6 PDZ protein targets Dlg, Scribble, Magi-1, Magi-3, PSD95, and Mupp1 were not changed by HPV8 E6. Decreased protein levels of syntenin-2 were observed in cell extracts from PHEK expressing HPV5, -8, -16, -20, and -38 E6 but not in HPV1 and -4 E6-positive keratinocytes. Surprisingly, HPV16 E6 also repressed transcription of syntenin-2 but with a much lower efficiency than HPV8 E6. In healthy human skin, syntenin-2 expression is localized in suprabasal epidermal layers. In organotypic skin cultures, the differentiation-dependent expression of syntenin-2 was absent in HPV8 E6- and E6E7-expressing cells. In basal cell carcinomas of the skin, syntenin-2 was not detectable, whereas in squamous cell carcinomas, expression was located in differentiated areas. Short hairpin RNA-mediated knockdown of syntenin-2 led to an inhibition of differentiation and an increase in the proliferation capacity in PHEK. These results identified syntenin-2 as the first PDZ domain protein controlled by HPV8 and HPV16 at the mRNA level.

Comparative analysis of recombinant Human Papillomavirus 8 L1 production in plants by a variety of expression systems and purification methods

Human papillomavirus 8 (HPV-8), one of the high-risk cutaneous papillomaviruses (cHPVs), is associated with epidermodysplasia verruciformis and nonmelanoma skin cancer in immuno-compromised individuals. Currently, no vaccines against cHPVs have been reported; however, recent studies on cross-neutralizing properties of their capsid proteins (CP) have fostered an interest in vaccine production against these viruses. We examined the potential of producing HPV-8 major CP L1 in Nicotiana benthamiana by agroinfiltration of different transient expression vectors: (i) the binary vector pBIN19 with or without silencing suppressor constructs, (ii) the nonreplicating Cowpea mosaic virus-derived expression vector pEAQ-HT and (iii) a replicating Tobacco mosaic virus (TMV)-based vector alone or with signal peptides. Although HPV-8 L1 was successfully expressed using pEAQ-HT and TMV, a 15-fold increase was obtained with pEAQ-HT. In contrast, no L1 protein could be immune detected using pBIN19 irrespective of whether silencing suppressors were coexpressed, although such constructs were required for identifying L1-specific transcripts. A fourfold yield increase in L1 expression was obtained when 22 C-terminal amino acids were deleted (L1ΔC22), possibly eliminating a nuclear localization signal. Electron microscopy showed that plant-made HPV-8 L1 proteins assembled in appropriate virus-like particles (VLPs) of T = 1 or T = 7 symmetry. Ultrathin sections of L1ΔC22-expressing cells revealed their accumulation in the cytoplasm in the form of VLPs or paracrystalline arrays. These results show for the first time the production and localization of HPV-8 L1 protein in planta and its assembly into VLPs representing promising candidate for potential vaccine production.

Human papillomavirus 8 E6 disrupts terminal skin differentiation and prevents pro-Caspase-14 cleavage

Expression of the betapapillomavirus (betaPV) E6/E7 genes has been shown to impair both keratinocyte differentiation and apoptosis. Especially late-terminal keratinocyte differentiation shares certain aspects with apoptosis, such as fragmentation of DNA and activation of caspases. Here we investigated the disruption of keratinocyte differentiation in organotypic skin (raft) cultures of primary (PHK) and immortalized (N/TERT) human keratinocytes, in particular by human papillomavirus (HPV)8. Immunohistochemical analysis of HPV5 and HPV8 E6/E7-expressing PHK revealed thickening of the rafts and complete absence of stratum corneum formation, even after 18 days of culture. This phenotype was confirmed in N/TERT raft cultures. When expressed separately, the aberrant morphology was observed only in rafts expressing E6, not E7. Immunofluorescence analysis of HPV8 E6 PHK rafts showed an increase in number and size of Filaggrin- and Caspase-14-positive cells in the granular layer. In raft lysates analyzed by western-blot, the presence of pro-Caspase-14 in the differentiated keratinocytes was confirmed, but in the HPV8 E6 rafts none of the Caspase-14 subunits were detected. In conclusion, in the raft system, HPV8 E6 prevented late-terminal keratinocyte differentiation resulting in an accumulation of Filaggrin and pro-Caspase-14-positive cells in the absence of stratification. This differentiation arrest was accompanied by the failure to express Caspase-14 subunits, suggesting absence of Caspase-14 activation and probable abrogation of Filaggrin maturation in HPV8 E6-expressing keratinocytes.

Seropositivity for human papillomavirus and incidence of subsequent squamous cell and basal cell carcinomas of the skin in patients with a previous nonmelanoma skin cancer

BACKGROUND

Infection with human papillomaviruses (HPVs) is a risk factor for several epithelial cancers, but its relationship with keratinocyte tumours has not yet been established. Objective  In this prospective study we investigated the possible role of different HPVs in the incidence of a subsequent nonmelanoma skin cancer (NMSC).

METHODS

One hundred and fifty-three patients with squamous cell carcinoma (SCC) and basal cell carcinoma (BCC) enrolled in a previous case-control study were re-contacted, and a follow-up visit was offered. Demographic and clinical data, date of first NMSC presentation, Fitzpatrick skin type and history of NMSC during the follow-up period were ascertained. Recurrences and new second cancers were considered together as 'outcomes' in time-to-event analyses and in Cox proportional hazard models.

RESULTS

Clinical data were obtained in 107 patients. HPV seropositivity at baseline was strongly associated with the risk of developing a second SCC after 5 years for a number of beta and gamma HPV types. For example, HPV-24-seropositive patients with an SCC at baseline had a 4-fold increased risk of developing a subsequent SCC (hazard ratio 4·35, 95% confidence interval 1·2-15·6, P = 0·024). No association between serological status for any HPV type tested and an increased risk of BCC was found.

CONCLUSIONS

We observed a consistent pattern of a positive association between seropositivity for beta and gamma HPV types and the risk of a subsequent SCC in patients with a previous SCC. Our data corroborate the results of previous case-control studies and may spur further prospective studies on the causal role of HPVs in NMSC.

Intradermal injection of PPD as a novel approach of immunotherapy in anogenital warts in pregnant women

Immunotherapy for treatment of recalcitrant warts was used through different modalities including intralesional injection of purified protein derivative (PPD), which is an extract of Mycobacterium tuberculosis, used for testing exposure to tuberculin protein, either from a previous vaccination or from the environment. This method is used to evaluate the efficacy of a new approach of intradermal injection of PPD in the treatment of anogenital warts in pregnant women. A total of 40 pregnant women, aged 20-35 years, and presented with anogenital warts were enrolled in this study. Human papillomavirus (HPV) typing was done using the GP5+/GP6+ PCR assay. The patients were treated with weekly injections of PPD given intradermally in the forearms, and evaluated for the response regularly. HPV type-6 was the predominant genotype (67.5%). Overall, the improvement in this study was 85% and was related to the extent of tuberculin reactivity. Nineteen (47.5%) patients demonstrated complete clearance, 15 (37.5%) had partial response, and three (7.5%) had minimal response. Three (7.5%) cases did not respond to treatment. Side effects were minimal and insignificant. Treatment of anogenital warts in pregnant women with intradermal injection of PPD was found to be a unique, safe, and effective modality of immunotherapy.

Detection of human papillomavirus DNA in feline premalignant and invasive squamous cell carcinoma

Squamous cell carcinoma (SCC) is the most common malignant cutaneous and oral neoplasm of cats. Papillomavirus (PV) DNA has been identified in a proportion of feline Bowenoid in situ carcinomas (BISCs), cutaneous SCCs and a single oral SCC, but its exact role in the pathogenesis remains unknown. In humans, it has been suggested that ultraviolet (UV) light and human PV (HPV) may act as cofactors in cutaneous SCC carcinogenesis. Little is known about the influence of UV light on PV prevalence in feline cutaneous lesions, including actinic keratosis (AK). Additionally, PV prevalence in noncutaneous feline lesions, including oral SCC, is largely not known. This study aimed to determine the presence of PV in 84 cats with premalignant and invasive SCC from cutaneous and noncutaneous sites using polymerase chain reaction and to investigate an association with UV light. Papillomaviral DNA was amplified from two of 12 cases of AK, seven of 22 BISCs, nine of 39 cutaneous SCCs and two of 35 non-cutaneous SCCs. Of the PV DNA sequenced, 50% was most similar to HPV of the genus Betapapillomavirus, while the other 50% was most similar to Felis domesticus PV type 2. Exposure to UV was not associated with an increase in PV for cutaneous SCC. The results of this study suggest that in the cat, HPV DNA may be detectible within a higher percentage of squamous lesions than previously demonstrated, UV exposure may not be a confounder for PV presence, and noncutaneous lesions may have a low prevalence of PV.

The Association between cutaneous squamous cell carcinoma and betapapillomavirus seropositivity: a cohort study

BACKGROUND

It is currently unclear whether betapapillomaviruses (betaPV) play a role in the etiology of cutaneous squamous cell carcinoma (SCC). We investigated the association between betaPV antibodies and subsequent SCC in a population-based cohort study.

METHODS

Serum samples were collected in 1992 and/or 1996 from 1,311 participants of the community-based Nambour Skin Cancer Study. These were tested for the presence of L1 antibodies against 21 different betaPV types. Histologically diagnosed SCCs were ascertained through three full-body skin examinations and linkage with the local pathology laboratories. We used age- and sex-adjusted Cox proportional hazards models to analyze the relationship between betaPV antibodies and SCC occurrence from 1992 until 2007.

RESULTS

SCC was newly diagnosed in 150 people. No associations were found between the presence of any betaPV L1 antibodies and the occurrence of SCC (HR = 1.0), and stratification by sex, skin color, and sunburn propensity did not affect these results. However, among people who were less than 50 years old in 1992, the presence of betaPV antibodies was associated with a two-fold increased risk of SCC. There was no significant association between antibodies to any individual betaPV type examined and the later development of SCC.

CONCLUSIONS

Whether betaPV infection of the skin, and indirectly betaPV antibodies, are involved in the oncogenic process in the general population remains unclear, and this longitudinal study provides only limited support.

IMPACT

This study emphasizes the need for additional longitudinal studies of HPV (human papilloma virus) and SCC, to avoid the possibility of reverse causality in case--control studies.

The combined influence of oral contraceptives and human papillomavirus virus on cutaneous squamous cell carcinoma

The vast majority of cutaneous squamous cell carcinoma (CSCC) will occur in those with fair complexion, tendency to burn, and high ultraviolet radiation (UVR) exposure. Organ transplant recipients also are an important population at great risk for CSCC. An association has been reported between oral contraceptive (OC) use, human papillomavirus virus (HPV) and cervical cancer, and there could be a similar association for CSCC. The cutaneous HPV β-E6 protein, a close cousin of the transformative E6 protein underlying anogenital cancers, has been shown to inhibit apoptosis in response to UVR damage and stimulate morphologic transformation in rodent fibroblast cell lines. Furthermore, OC use has been shown to enhance HPV transcription and may contribute to CSCC risk through this pathway.

Quantification of beta-human papillomavirus DNA by real-time PCR

Quantitative PCR with hybridization probes allows the reliable quantification of viral DNA sequences in clinical samples with a dynamic range and sensitivity that cannot be achieved with other methods. The technical background for the establishment of protocols is described and established protocols are presented to estimate the viral load per cell of frequently occurring betapapillomaviruses (HPV5, -8, -15, -20, -23, -24, -36 and -38) in skin tumors, healthy skin and hair bulbs. This approach accurately adjusts dilution series of reference DNA of different viral types relative to pUC18, which is crucial for comparative analyses and for interlaboratory standardization. The type-specific determination of beta-HPV DNA loads is an important research tool toward discrimination between low-level persistence and activated possibly pathologically relevant infections. The analysis of 24 samples, starting with DNA extraction and followed by HPV typing and quantification of-on average-three of the described HPV types takes about 2 d.

Squamous cell carcinomas are associated with verrucokeratotic cutaneous lesions but not with common warts in organ-transplant patients. A case-control study

BACKGROUND

Warts are thought to be associated with the development of squamous cell carcinoma (SCC) in organ transplant patients. We investigated the association between the different types of warts and SCC in organ transplant patients.

METHODS

A prospective multicenter case-control study was conducted. Cases were patients with a kidney or heart transplant who were referred for a SCC. Controls were organ transplant patients without SCC, individually matched for age, gender, type of organ transplant (heart or kidney), skin phototype, time from transplantation, and center. Four types of warts: flat warts, verrucae vulgares (including palmo-plantar warts and common warts), verrucous papilloma, and verrucokeratotic lesions were compared between cases and controls using conditional logistic regression.

RESULTS

Ninety-nine cases and 169 controls were included. In multivariate analysis, number of rejections, azathioprine, prednisolone and anti-lymphocyte anti-serum or anti-CD3 monoclonal antibodies use, cumulative sun exposure, actinic keratosis, and verrucokeratic lesions (odds ratio [OR] 16.50; 95% confidence interval [CI] 2.82-96.80) were independently associated with SCC, whereas the association with verrucous papilloma was borderline significant (OR 2.21; 95% CI 0.97-8.15). The association between the presence of at least one of these two types of warts (verruco-keratotic lesions and verrucous papilloma) and the occurrence of SCC was highly significant (OR 18.36; 95% CI 3.03-111) when these warts were located in the same area than SCC, whereas no significant association was evidenced when these warts were located in another area (OR 1.02; 95% CI 0.13-5.79).

CONCLUSION

Verrucous papilloma and mainly verrucokeratotic lesions are strongly associated with the risk of SCC in organ transplant patients, whereas the most typical types of warts: verrucae vulgares and flat warts, are not.

Lack of association between the presence and persistence of betapapillomavirus DNA in eyebrow hairs and betapapillomavirus L1 antibodies in serum

Betapapillomavirus (betaPV) DNA and seroresponses are highly prevalent in the general population and both are frequently used as infection markers in epidemiological studies to elucidate an association with cutaneous squamous cell carcinoma (SCC). Little is known about the natural history of betaPV infection and the aspects of infection that drive antibody responses. To investigate the relationship between these markers, this study assessed whether the presence or persistence of betaPV DNA in eyebrow hairs and L1 antibodies of the same betaPV type co-occurred more frequently than would be expected by chance in both a cross-sectional assessment and a longitudinal study. betaPV DNA in plucked eyebrow hairs and L1 antibodies in serum were measured in 416 participants of the Australian community-based Nambour Skin Cancer Study in 1996. Similar data were available for a subset of 148 participants in 2003. Observed co-occurrence of betaPV DNA and antibodies was compared with expected values based on prevalence. A case-wise concordance index was used to calculate the overall concordance of betaPV DNA and antibodies of the same type. No significant associations were found between the presence or persistence of betaPV DNA and antibody responses. The age and sex of the host did not influence the association, and nor did SCC status or a history of sunburns. It was concluded that betaPV antibody responses in adults are not primarily driven by betaPV infection as measured in eyebrow hairs. Other factors, such as viral load, may play a more pivotal role in the induction of detectable seroresponses.

Human papillomavirus infection and squamous cell carcinoma of the conjunctiva

Background:

Squamous cell carcinoma of the conjunctiva (SCCC) is associated with HIV-related immunosuppression, but human papillomavirus virus (HPV) is also suspected to have a role. We carried out a case–control study to assess the role of cutaneous and mucosal HPV types in SCCC, conjunctival dysplasia, and their combination (SCCC/dysplasia) in Uganda.

Methods:

We compared HPV prevalence in frozen biopsies from 94 SCCC cases (79 of whom were found to be HIV-positive), 39 dysplasia cases (34 HIV-positive), and 285 hospital controls (128 HIV-positive) having other eye conditions that required surgery. Highly sensitive PCR assays that detect 75 HPV types were used. Odds ratios (ORs) and 95% confidence intervals (CIs) were computed, adjusting for, or stratifying by age, sex, and HIV status.

Results:

Cutaneous HPV types were detected in 45% of SCCC cases, 41% of dysplasia cases and 11% of controls. Human papillomavirus virus 5 and 8 were the most common types in SCCC, and most often occurred in combination with other types. Associations were observed between SCCC/dysplasia and detection of both single (OR=2.3; 1.2–4.4) and multiple (OR=18.3; 6.2–54.4) cutaneous HPV types, and were chiefly based on findings in HIV-positive patients. Cutaneous HPV infections were rarely observed among HIV-negative patients and the association with SCCC/dysplasia was not significant (OR=2.4; 0.6–9.6) among them. Squamous cell carcinoma of the conjunctiva/dysplasia risk and mucosal HPV types were not associated in either HIV-positive or HIV-negative patients.

Conclusions:

We detected cutaneous HPV types in nearly half of SCCC/dysplasia cases and often multiple types (HPV5 and 8 being most common). The role of HIV (confounder or strong enhancer of cutaneous HPV carcinogenicity) is still uncertain.

Prevalence and multiplicity of cutaneous beta papilloma viruses in plucked hairs depend on cellular DNA input

In view of the low loads of beta human papillomaviruses in skin samples, amounts of cellular DNA used in qualitative PCR may become limiting for virus detection and introduce variations in prevalence and multiplicity. This issue was explored within the context of a multicentre study and increasing prevalence and multiplicity was found with increasing input amounts of cellular DNA extracted from hair bulbs. To improve the quality and comparability between different epidemiologic studies ideally equal amounts of cellular DNA should be employed. When cellular DNA input varies this should be clearly taken into account in assessing viral prevalence and multiplicity.