Cutaneous Human Papillomavirus in Head and Neck Squamous Cell Carcinomas

Phosphorylation of E2 Serine Residue 402 Is Required for the Transcription and Replication of the HPV5 Genome

Cutaneous human papillomavirus type 5 (HPV5) belongs to the supposedly oncogenic β-HPVs associated with specific types of skin and oral cavity cancers. Three viral proteins, namely, helicase E1 and transcription factors E2 and E8^E2, are master regulators of the viral life cycle. HPV5 E2 is a transcriptional activator that also participates in the E1-dependent replication and nuclear retention of the viral genome, whereas E8^E2 counterbalances the activity of E2 and inhibits HPV transcription and replication. In the present study, we demonstrate that the HPV5 E2 protein is extensively phosphorylated by cellular protein kinases, and serine residue 402 (S402) is the highest scoring phosphoacceptor site. This residue is located within a motif conserved among many β-HPVs and in the oncogenic HPV31 α-type. Using the nonphosphorylatable and phosphomimetic mutants, we demonstrate that phosphorylation of the E2 S402 residue is required for the transcription and replication of the HPV5 genome in U2OS cells and human primary keratinocytes. Mechanistically, the E2-S402-phopshodeficient protein is unable to trigger viral gene transcription and has an impaired ability to support E1-dependent replication, but the respective E8^E2-S213 mutant displays no phenotype. However, phosphorylation of the E2 S402 residue has no impact on the E2 stability, subcellular localization, self-assembly, DNA-binding capacity, and affinity to the E1 and BRD4 proteins. Further studies are needed to identify the protein kinase(s) responsible for this phosphorylation. IMPORTANCE Human papillomavirus type 5 (HPV5) may play a role in the development of specific types of cutaneous and head and neck cancers. The persistence of the HPV genome in host cells depends on the activity of its proteins, namely, a helicase E1 and transcription/replication factor E2. The latter also facilitates the attachment of episomal viral genomes to host cell chromosomes. In the present study, we show that the HPV5 E2 protein is extensively phosphorylated by host cell protein kinases, and we identify serine residue 402 as the highest scoring phosphoacceptor site of E2. We demonstrate that the replication of the HPV5 genome may be blocked by a single point mutation that prevents phosphorylation of this serine residue and switches off the transcriptional activity of the E2 protein. The present study contributes to a better understanding of β-HPV5 replication and its regulation by host cell protein kinases.

Mucosal and cutaneous human papillomaviruses in head and neck squamous cell papillomas

BACKGROUND

Conflicting data exist regarding the contribution of human papillomavirus (HPV) to the development of head and neck squamous cell papillomas.

METHODS

Formalin-fixed paraffin-embedded papillomas were tested for 28 mucosal and 79 cutaneous HPVs using polymerase chain reaction (PCR)-based methods.

RESULTS

Eighty-three papillomas (43 oropharyngeal, 31 oral, 6 laryngeal, and 3 nasopharyngeal) were analyzed. Twenty-four samples (28.9%) harbored mucosal HPVs: 3 oropharyngeal (6.9%), 15 oral (48.3%), 4 laryngeal (66.7%), and 2 nasopharyngeal papillomas (66.7%). Eighty-one cases were also tested for cutaneous HPVs, detected in 16 lesions (19.7%): 11 (13.5%) harbored only cutaneous types, and 5 (6.2%) were positive for both cutaneous and mucosal HPVs. Among these 81 cases, prevalence of mucosal and/or cutaneous HPV infection was 43.2%.

CONCLUSION

HPV DNA detection in a fraction of head and neck papillomas supports the role of HPV in their development. However, other markers need to be considered to confirm the association of HPV infection with these lesions. © 2016 Wiley Periodicals, Inc. Head Neck 39: 254-259, 2017.

Searching beyond the usual papillomavirus suspects in squamous carcinomas of the vulva, penis and head and neck

Human Papillomaviruses (HPVs) are involved in the etiology of anogenital and head and neck cancers. The HPV DNA prevalence greatly differs by anatomical site. Indeed, the high rates of viral DNA prevalence in anal and cervical carcinomas contrast with the lower fraction of cancer cases attributable to HPVs in other anatomical sites, chiefly the vulva, the penis and head and neck. Here we analyzed 2635 Formalin Fixed Paraffin Embedded surgical samples that had previously tested negative for the presence of HPVs DNA using the SPF10/DEIA procedure, in order to identify the presence of other PVs not explicitly targeted by standard molecular epidemiologic approaches. All samples were reanalyzed using five broad-PV PCR primer sets (CP1/2, FAP6064/FAP64, SKF/SKR, MY9/MY11, MFI/MFII) targeting the main PV main clades. In head and neck carcinoma samples (n=1141), we recovered DNA from two BetaHPVs, namely HPV20 and HPV21, and from three cutaneous AlphaPVs, namely HPV2, HPV57 and HPV61. In vulvar squamous cell carcinoma samples (n=902), we found one of the samples containing DNA of one cutaneous HPV, namely HPV2, and 29 samples contained DNA from essentially mucosal HPVs. In penile squamous cell carcinoma samples (n=592), we retrieved the DNA of HPV16 in 16 samples. Our results show first that the SPF10/DEIA is very sensitive, as we recovered only 2.1% (55/2635) false negative results; second, that although the DNA of cutaneous HPVs can be detected in cancer samples, their relative contribution remains anyway minor (0.23%; 6/2635) and may be neglected for screening and vaccination purposes; and third, their contribution to malignancy is not necessarily warranted and needs to be elucidated.

Beta-HPV types in patients with head and neck pathology and in healthy subjects

BACKGROUND

Human papillomaviruses (HPV) are a heterogeneous group of viruses classified into five genera. The beta-HPV type (beta-PV) infection is very common but mostly asymptomatic in immunocompetent individuals. However, beta-PVs play a role in Epidermodysplasia verruciformis and possibly in non-melanoma skin cancer. Head and neck cancer (HNC) is a common cancer type worldwide and high-risk alpha-PV involvement in HNC has been extensively studied but beta-PV types have rarely been the focus of such studies.

OBJECTIVES

To evaluate the prevalence of beta-PV types in HNC, subjects with non-malignant or potentially pre-malignant oral lesions, and healthy controls.

STUDY DESIGN

The frequency of different beta-PVs in samples from oral (n=35) and oropharyngeal (n=35) cancer patients, gender- and age-matched healthy controls (n=70), and subjects with various non-malignant or potentially pre-malignant oral lesions (n=102) was assessed by a highly sensitive, bead-based, multiplex genotyping assay.

RESULTS

Overall, 54.8% of all tested samples contained at least one beta-PV type. Even though the correlation between types found in lavage and tissue specimens from cancer patients was low, there was a large statistically significant difference between oropharyngeal cancer patients and matched controls for HPV5 (P=0.003; OR=15.58) and between both oral (P=0.026; OR=5.7) and oropharyngeal cancer patients (P=0.002; OR=25.5) and controls for HPV122. In addition, there was no correlation between the prevalence of alpha and beta-PVs in the study patients.

CONCLUSION

The study provides new data on the prevalence of beta-PVs in HNC. HPV5 was found significantly associated with HNC as already observed by other studies. Additionally, the significant association of HPV122 with HNC might warrant further study as this type has not been extensively studied so far.

Prevalence of human papillomavirus in head and neck cancers in European populations: a meta-analysis

BACKGROUND

Infection with human papillomavirus (HPV) is necessary for the development of cervical carcinoma. By contrast, the role of HPV in the pathogenesis of other malignancies, such as head and neck cancers, is less well characterised. This study aimed to address key information gaps by conducting a systematic review and meta-analysis of the prevalence of HPV infection in head and neck cancers, focusing on data for European populations.

METHODS

MEDLINE, Embase and grey literature sources were systematically searched for primary studies that were published in English between July 2002 and July 2012, and which reported on the prevalence of HPV infection in head and neck cancers in European populations. Studies on non-European populations, those not published in English, and those assessing patients co-infected with human immunodeficiency virus were excluded. Eligible studies were combined in a meta-analysis. In addition, the potential statistical association between the head and neck cancers and certain HPV types was investigated.

RESULTS

Thirty-nine publications met the inclusion criteria. The prevalence of HPV of any type in 3,649 patients with head and neck cancers was 40.0% (95% confidence interval, 34.6% to 45.5%), and was highest in tonsillar cancer (66.4%) and lowest in pharyngeal (15.3%) and tongue (25.7%) cancers. There were no statistically significant associations between the HPV types analysed and the geographical setting, type of sample analysed or type of primer used to analyse samples in head and neck cancers.

CONCLUSIONS

The prevalence of HPV infection in European patients with head and neck cancers is high but varies between the different anatomical sites of these malignancies. There appears to be no association between HPV type and geographical setting, type of samples analysed or type of primer used to analyse samples in such cancers.

High genital prevalence of cutaneous human papillomavirus DNA on male genital skin: the HPV Infection in Men Study

Background

The genital skin of males hosts a diversity of HPV genotypes and uncharacterized HPV genotypes. Previously we demonstrated that a specific viral genotype was not identified in 14% of all genital specimens (i.e., HPV unclassified specimens) using the Roche Linear Array method. Our goal was to identify and assess the prevalence of individual HPV types among genital HPV unclassified specimens collected in the HIM Study population, at enrollment, and examine associations with socio-demographic and behavioral characteristics.

Methods

Genital skin specimens of men that were considered unclassified (HPV PCR positive, no genotype specified) at enrollment were typed by sequencing amplified PGMY09/11 products or cloning of PGMY/GP+ nested amplicons followed by sequencing. PGMY/GP+ negative specimens were further analyzed using FAP primers. HPV type classification was conducted through comparisons with sequences in the GenBank database.

Results

Readable nucleotide sequences were generated for the majority of previously unclassified specimens (66%), including both characterized (77%) and yet uncharacterized (23%) HPV types. Of the characterized HPV types, most (73%) were Beta [β]-HPVs, primarily from β-1 and β-2 species, followed by Alpha [α]-HPVs (20%). Smokers (current and former) were significantly more likely to have an α-HPV infection, compared with any other genus; no other factors were associated with specific HPV genera or specific β-HPV species.

Conclusions

Male genital skin harbor a large number of β-HPV types. Knowledge concerning the prevalence of the diverse HPV types in the men genital is important to better understand the transmission of these viruses.

Electronic supplementary material

The online version of this article (doi:10.1186/s12879-014-0677-y) contains supplementary material, which is available to authorized users.

Both mucosal and cutaneous papillomaviruses are in the oral cavity but only alpha genus seems to be associated with cancer

BACKGROUND

Human papillomaviruses are associated with invasive cancers in the cervical, anogenital, and oropharyngeal areas. Persistent HPV infections, particularly with high-risk HPV such as HPV 16, are involved in the carcinogenesis of a subset of oropharyngeal cancers. The majority of published studies on HPV prevalence in these tumors concentrated on identifying high-risk mucosal types.

OBJECTIVES

To determine the HPV type specific prevalence in different samples collected from the oral cavity of three groups of patients: (A) healthy (n=25); (B) non-malignant lesions (n=47); and (C) cancers (n=78).

STUDY DESIGN

To evaluate the prevalence of HPV genotypes in the oral cavity, samples were analyzed by PCR with: MY09/MY11 followed by GP5+/GP6+, CP65/CP70 followed by CP66/CP69, and FAP59/FAP64 primers. The presence of viral transcripts was ascertained by RT-PCR with specific primers for the E7 region.

RESULTS

Mucosal HPV types were associated with the presence of cancers. This trend was statistically significant if the analysis was performed for HPV 16 (p=0.04), which is the most prevalent type detected in oropharyngeal cancers. Conversely, cutaneous HPVs were associated with non-malignant lesions (p=0.007). The multiple correspondence analysis confirmed these data. Viral transcripts of only mucosal HPVs were detected in non-malignant lesions and cancers.

CONCLUSIONS

Different types of HPVs infect the oral epithelium, but only the mucosal types, particularly HPV 16, are clearly associated with tumors. The discovery that cutaneous HPVs are associated with potential malignant oral disorders brings other data to understand the significance of their presence in the oral cavity.

Murine skin and vaginal mucosa are similarly susceptible to infection by pseudovirions of different papillomavirus classifications and species

Depending upon viral genotype, productive papillomavirus infection and disease display preferential tropism for cutaneous or mucosal stratified squamous epithelia, although the mechanisms are unclear. To investigate papillomavirus entry tropism, we used reporter pseudovirions based on various cutaneous and mucosal papillomavirus species, including the recently identified murine papillomavirus. Pseudovirus transduction of BALB/c mice was examined using an improved murine skin infection protocol and a previously developed cervicovaginal challenge model. In the skin, HPV5, HPV6, HPV16, BPV1 and MusPV1 pseudovirions preferentially transduced keratinocytes at sites of trauma, similar to the genital tract. Skin infection, visualized by in vivo imaging using a luciferase reporter gene, peaked between days 2-3 and rapidly diminished for all pseudovirion types. Murine cutaneous and genital tissues were similarily permissive for pseudovirions of HPV types 5, 6, 8, 16, 18, 26, 44, 45, 51, 58 and animal papillomaviruses BPV1 and MusPV1, implying that papillomavirus' tissue and host tropism is governed primarily by post-entry regulatory events in the mouse.