Cutaneous human papillomaviruses found in sun-exposed skin: Beta-papillomavirus species 2 predominates in squamous cell carcinoma

Risk Factors and Innovations in Risk Assessment for Melanoma, Basal Cell Carcinoma, and Squamous Cell Carcinoma

Skin cancer is the most frequently diagnosed cancer globally and is preventable. Various risk factors contribute to different types of skin cancer, including melanoma, basal cell carcinoma, and squamous cell carcinoma. These risk factors encompass both extrinsic, such as UV exposure and behavioral components, and intrinsic factors, especially involving genetic predisposition. However, the specific risk factors vary among the skin cancer types, highlighting the importance of precise knowledge to facilitate appropriate early diagnosis and treatment for at-risk individuals. Better understanding of the individual risk factors has led to the development of risk scores, allowing the identification of individuals at particularly high risk. These advances contribute to improved prevention strategies, emphasizing the commitment to mitigating the impact of skin cancer.

Das kutane Mikrobiom bei Hautkrebs - Eine systematische Übersicht: The cutaneous microbiome in skin cancer - A systematic review

Die Hautkrebs‐Inzidenz ist über die vergangene halbe Dekade weltweit gestiegen und mit signifikanter Morbidität und Mortalität assoziiert. Jüngste Fortschritte in der molekularen Diagnostik ermöglichen ein besseres Verständnis von Mikrobiom‐Veränderungen bei diesen Erkrankungen. Allerdings ist die Literatur zum kutanen Mikrobiom bei Hautkrebs nach wie vor heterogen und spärlich. Wir führten eine systematische Überprüfung durch, um die bestehende Literatur sowie ihren Nutzen bezüglich mikrobiombasierter Biomarker zu evaluieren. Die Datenbanken (PubMed, Medline, EMBASE, GoogleScholar) wurden zwischen Juni und Juli 2022 in Übereinstimmung mit den PRISMA‐Richtlinien gesichtet.

Insgesamt wurden 1.543 Artikel ermittelt, von denen 16 in die Übersicht eingeschlossen wurden (11 Artikel zu epithelialen Hauttumoren und 5 Artikel zu Melanomen). Bei Plattenepithelkarzinomen (PEKs) und aktinischer Keratose (AK) wird im Vergleich zu gesunder Haut eine erhöhte Prävalenz von Staphylococcus (S.) aureus bei gleichzeitigem Rückgang der kommensalen Organismen festgestellt. Das Mikrobiom des Melanoms scheint sich zwar von dem der gesunden Haut zu unterscheiden, doch stehen nur wenige Daten für aussagekräftige Schlussfolgerungen zur Verfügung.

Die vorliegende Übersicht fasst die aktuellen Erkenntnisse zum Mikrobiom bei epithelialem Hautkrebs und Melanom zusammen. Sie zeigt, dass sich das Mikrobiom bei diesen Erkrankungen von dem gesunder Haut unterscheidet und dass an dieser Dysbiose sowohl pathogene als auch kommensale Organismen beteiligt sind.

The cutaneous microbiome in skin cancer - A systematic review

The overall incidence of skin cancer has risen over the past half a decade worldwide and is associated with significant morbidity and mortality. Recent advances in molecular testing have allowed us to better characterize microbiome alterations in skin cancer. However, literature specific to skin microbiome and skin cancer remain heterogenous and scattered. A systematic review was performed to identify the existing literature and its usefulness in providing microbiome-based biomarkers. A search of the databases (PubMed, Medline, EMBASE, GoogleScholar) was conducted from June to July 2022 in accordance with the PRISMA guidelines. A total of 1,543 articles were identified, of which 16 were selected for inclusion in the review (11 articles on cancer of the keratinocytes and 5 articles on melanoma). Increased Staphylococcus (S.) aureus prevalence with decline in commensal organisms is seen in squamous cell carcinoma (SCC) and actinic keratosis (AK), compared to healthy skin. While the microbiome of melanoma appears to be distinct from healthy skin, limited data is available to draw meaningful conclusions. Our review summarizes the current evidence on the microbiome of keratinocyte skin cancers and melanoma. The study establishes that the microbiome of these cancers is altered from healthy skin and that this dysbiosis involves both pathogenic and commensal organisms.

Molecular investigation of some DNA viruses in mucosal melanoma: Case-control study

The association between viral infections and both cutaneous and mucosal melanoma (MM) has not been fully investigated. Here, we assessed the prevalence of the DNA of a broad range of viruses in 31 MMs and 15 biopsies of healthy mucosa (HM) using molecular methods. The parvoviruses CuV and B19V, herpesviruses HSV1, HSV2, EBV, HHV6, and HHV8, polyomavirus MCPyV, and α-HPVs were not detected, or rarely found, in MMs, and in HM, of the digestive, respiratory, and female genital tract. The overall prevalence of β-HPV in MMs was not significantly higher compared to that in HM (70.9% and 53.3% respectively; p = 0.514). However, the number of MMs positive for β-HPV types belonging to Species 3 and 5 and for some viral types belonging to Species 1, 2, 3, and 5 were significantly higher compared with HM (p < 0.05). Moreover, compared to HM, the MM samples contained a significantly higher number of β-HPV types, mainly belonging to Species 1, 3, and 5 (p < 0.05). Our data, although suggesting a role for certain β-HPV types in MM oncogenesis, require additional investigation in larger populations to support this hypothesis.

The role of HPV in keratinocyte skin cancer development: A systematic review

Keratinocyte skin cancers are the most frequent malignancy, accounting for approximately 30% of all cancers. Although beta genus HPV are the main etiologic agents for squamous cell carcinoma development in patients with epidermodysplasia verruciformis and organ transplant recipients, their role in non-melanoma skin cancer (NMSC) progression in the general population remains controversial. The aim of our review is to summarize current scientific data and to systematically analyse evidence regarding the role of HPV in keratinocyte skin cancers. A total of 2284 patients were included, of which 724 with actinic keratoses, 290 with Bowen's disease, 949 with cutaneous squamous cell carcinomas and 321 with keratoacanthomas. In the case of actinic keratoses, the majority were positive for beta (n = 372, 58.49%) and gamma HPV (n = 256, 40.25%) and only a few (n = 6, 0.94%) were positive for alpha subtypes. Similarly, most of the cutaneous squamous cell carcinomas were positive for beta (n = 248, 55.98%) and gamma HPV (n = 172, 33.82%) and 23 cases (2.42%) were positive for alpha subtypes. Bowen's disease lesions were mostly positive for beta (n = 43, 55.84%) and alpha HPV (n = 30, 38.96%), in contrast to the gamma genus (n = 4, 5.19%). Keratoacanthomas showed a high distribution among beta genus (n = 79, 50.31%) and an equal proportion between alpha (n = 39, 24.84%) and gamma (n = 39, 24.84%) genera. Studies published so far identifying HPV in keratinocyte skin cancers reflect the difference in detection methods rather than a type-specific tendency towards either actinic keratoses, Bowen's disease, squamous cell carcinoma or keratoacanthoma. On the other hand, recent evidence regarding the role of HPV vaccination in patients with non-melanoma skin cancer brings into perspective the idea of a beta-HPV vaccine or a combined alpha and beta-HPV vaccine that could be used as an adjuvant treatment measure in patients with recalcitrant non-melanoma skin cancer.

Next generation L2-based HPV vaccines cross-protect against cutaneous papillomavirus infection and tumor development

Licensed L1-VLP-based immunizations against high-risk mucosal human papillomavirus (HPV) types have been a great success in reducing anogenital cancers, although they are limited in their cross-protection against HPV types not covered by the vaccine. Further, their utility in protection against cutaneous HPV types, of which some contribute to non-melanoma skin cancer (NMSC) development, is rather low. Next generation vaccines achieve broadly cross-protective immunity against highly conserved sequences of L2. In this exploratory study, we tested two novel HPV vaccine candidates, HPV16 RG1-VLP and CUT-PANHPVAX, in the preclinical natural infection model Mastomys coucha. After immunization with either vaccines, a mock control or MnPV L1-VLPs, the animals were experimentally infected and monitored. Besides vaccine-specific seroconversion against HPV L2 peptides, the animals also developed cross-reactive antibodies against the cutaneous Mastomys natalensis papillomavirus (MnPV) L2, which were cross-neutralizing MnPV pseudovirions in vitro. Further, both L2-based vaccines also conferred in vivo protection as the viral loads in plucked hair after experimental infection were lower compared to mock-vaccinated control animals. Importantly, the formation of neutralizing antibodies, whether directed against L1-VLPs or L2, was able to prevent skin tumor formation and even microscopical signs of MnPV infection in the skin. For the first time, our study shows the proof-of-principle of next generation L2-based vaccines even across different PV genera in an infection animal model with its genuine PV. It provides fundamental insights into the humoral immunity elicited by L2-based vaccines against PV-induced skin tumors, with important implications to the design of next generation HPV vaccines.

Exposome and Skin. Part 2. The Influential Role of the Exposome, Beyond UVR, in Actinic Keratosis, Bowen's Disease and Squamous Cell Carcinoma: A Proposal

Actinic keratosis (AK) is the main risk factor for the development of cutaneous invasive squamous cell carcinoma (SCC). It represents the first sign of severe chronic ultraviolet radiation exposure, which has a clear significant effect. Nevertheless, the skin is exposed to many other exposome factors which should be thoroughly considered. Our aim was to assess the impact of exposome factors other than ultraviolet radiation (UVR) on the etiopathology of AK and Bowen's disease (BD) and progression of AK to SCC and to design tailored prevention strategies. We performed an exhaustive literature search in September 2021 through PubMed on the impact of exposome factors other than UVR on AK, BD and SCC. We conducted several parallel searches combining terms of the following topics: AK, BD, SCC and microbiome, hormones, nutrition, alcohol, tobacco, viral infections, chemical contaminants and air pollution. Notably, skin microbiome studies have shown how Staphylococcus aureus infections are associated with AK and AK-to-SCC progression by the production of chronic inflammation. Nutritional studies have demonstrated how a caloric restriction in fat intake, oral nicotinamide and moderate consumption of wine significantly reduce the number of premalignant keratoses and SCC. Regarding lifestyle factors, both alcohol and smoking are associated with the development of SCC in a dose-dependent manner. Relevant environmental factors are viral infections and chemical contaminants. Human papillomavirus infections induce deregulation of cellular proliferation and are associated with AK, BD and SCC. In addition to outdoor jobs, occupations such as industrial processing and farming also increase the risk of developing keratoses and SCC. The exposome of AK will undoubtedly help the understanding of its etiopathology and possible progression to SCC and will serve as a basis to design tailored prevention strategies.

Cutaneous beta HPVs, sun exposure and risk of squamous and basal cell skin cancers in Australia

BACKGROUND

Sun exposure causes cutaneous squamous (SCC) and basal cell (BCC) carcinomas. Human papillomavirus (HPV) infection might cause SCC.

METHODS

We examined associations of beta and gamma HPV infection in skin-swab DNA and serum antibodies with skin cancer risk, and modification of the carcinogenic effects of sun exposure by them, in case-control studies of 385 SCC cases, 832 BCC cases and 1100 controls nested in an Australian prospective cohort study (enrolled 2006-2009).

RESULTS

Presence of beta-1 and beta-3 HPV DNA appeared to increase risks for SCC and BCC by 30%-40% (P adjusted <0.01). BCC was also associated with genus beta DNA, OR=1.48; 95%CI 1.10-2.00 (P adjusted <0.01). Associations were strengthened with each additional positive beta HPV DNA type: SCC (OR=1.07; 95%CI 1.02-1.12) and BCC (OR=1.06; 95%CI 1.03-1.10), P trend <0.01. Positivity to genus beta or gamma in serology, and genus gamma in DNA, was not associated with either cancer. There was little evidence that any beta HPV type was more strongly associated than others with either cancer. A weaker association of sun-exposure with SCC and BCC in the presence of beta-3 HPVs than in their absence suggests that beta-3 HPVs modify sun exposure's effect.

CONCLUSIONS

Our substantive findings are at the level of genus beta HPV. Like SCC, BCC risk may increase with increasing numbers of beta HPV types on skin.

IMPACT

The consistency in our findings that HPV infection may moderate the effects of sun exposure, the main environmental cause of SCC and BCC, merits further investigation.

Transcription of human papillomaviruses in nonmelanoma skin cancers of the immunosuppressed

Nonmelanoma skin cancer (NMSC) has a greatly increased incidence among the immunosuppressed and the DNA of human papillomavirus (HPV) is commonly found in these tumors. To investigate if there are any actively transcribed HPV infections in these tumors, we identified all skin cancers diagnosed after solid organ transplantation in Sweden during 1964-2011 (n = 7614 NMSCs) and requested the diagnostic tumor blocks from the corresponding pathology archives. For the present study, we selected diagnostic specimens from 345 NMSC and performed whole genome transcriptome analysis using NovaSeq (Illumina), in comparison with three cervical cancers. Although we obtained an abundance of high-quality paired reads per sample (median of 35 million reads), only 15 NMSC specimens contained HPV transcription. Three specimens had transcription of oncogenic anogenital HPVs (HPV16 and 56), six tumors had transcription of HPVs from the beta-2 species (three HPV38, two with HPV23 and one with HPV107) and then there was one observation each of transcription of HPVs 3, 26, 57, 147, 158, 168 and of two nonestablished HPV types belonging to the gamma genus. In conclusion, transcription of specific HPV types can be found in NMSC among the immunosuppressed, but this is not common.

Cutaneous viral infections associated with ultraviolet radiation exposure

The complex interplay between ultraviolet radiation (UVR) and cutaneous viral infections in the context of cancer etiology is challenging to unravel, given the limited information on the independent association between UVR and cutaneous viral infections. Using multiple biomarkers of infection with 24 types of cutaneous human papillomavirus (HPV) and 4 types of polyomaviruses (HPyV), we investigated cross-sectional associations with recent UVR exposure, using skin pigmentation measured by spectrophotometer. Age- and sex-adjusted associations between UVR and viral seropositivity, viral DNA present in eyebrow hairs (EBH) and skin swabs (SSW) were estimated using logistic regression. Beta-HPV seropositivity was associated with viral DNA positivity in EBH (OR = 1.40, 95% CI = 1.05-1.88) and SSW (OR = 1.86, 95% CI = 1.25-2.74). Similar associations were observed for Merkel cell polyomavirus. Participants in the highest tertile of UVR exposure were more likely to be seropositive for beta-HPV (OR = 1.81, 95% CI = 1.16-2.38), and have beta-HPV DNA in EBH (OR = 1.57, 95% CI = 1.06-2.33) and SSW (OR = 2.22, 95% CI = 1.25-3.96), compared to participants with the lowest tertile of UVR exposure. UVR exposure was positively associated with three different markers of beta-HPV infection. Therefore, future studies of HPV associated KC development should address more directly the role of HPV and UVR exposure as potential co-carcinogens.

Detection of a large spectrum of viral infections in conjunctival premalignant and malignant lesions

To study the interaction between HIV and other carcinogenic infections in conjunctival squamous cell carcinoma (SCC), we evaluated the presence of a broad spectrum of human viruses in conjunctiva specimens. Beta Human papillomavirus (HPV; n = 46), gamma HPV (n = 52), polyomaviruses (n = 12) and herpes viruses (n = 3) was determined in DNA extracted from 67 neoplastic and 55 non-neoplastic conjunctival tissues of HIV-positive and HIV negative subjects by Luminex-based assays. Next-generation sequencing (NGS) was also used to further characterize the presence of cutaneous HPVs. Detection of beta-2 HPV infections was associated with the risk of neoplasia (adjusted odds ratio [aOR] 3.0; 95% confidence interval [CI] 1.3-6.8), regardless of HIV status (HIV positive, aOR 2.6, 95% CI 0.9-7.7; HIV negative, aOR 3.5, 95% CI 0.9-14.4). EBV was strongly associated with the risk of neoplasia (aOR 12.0, 95% CI 4.3-33.5; P < .01) mainly in HIV individuals (HIV positive, aOR 57.5; 95% CI: 10.1-327.1; HIV negative aOR 2.6; 95% CI: 0.2-34.7). NGS allowed to identify 13 putative novel HPVs in cases and controls. Our findings suggest a role of beta HPV types and EBV, in conjunctival SCC. However, additional studies of viral expression in tumor tissue are required to confirm the causal association.

Transforming Properties of Beta-3 Human Papillomavirus E6 and E7 Proteins

The beta human papillomaviruses (HPVs) are subdivided into 5 species (beta-1 to beta-5), and they were first identified in the skin. However, the beta-3 species appears to be more highly represented in the mucosal epithelia than in the skin. Functional studies have also highlighted that beta-3 HPV49 shares some functional similarities with mucosal high-risk (HR) HPV16. Here, we describe the characterization of the in vitro transforming properties of the entire beta-3 species, which includes three additional HPV types: HPV75, HPV76, and HPV115. HPV49, HPV75, and HPV76 E6 and E7 (E6/E7), but not HPV115 E6 and E7, efficiently inactivate the p53 and pRb pathways and immortalize or extend the life span of human foreskin keratinocytes (HFKs). As observed for HR HPV16, cell cycle deregulation mediated by beta-3 HPV E6/E7 expression leads to p16INK4a accumulation, whereas no p16INK4a was detected in beta-2 HPV38 E6/E7 HFKs. As shown for HPV49 E6, HPV75 and HPV76 E6s degrade p53 by an E6AP/proteasome-mediated mechanism. Comparative analysis of cellular gene expression patterns of HFKs containing E6 and E7 from HR HPV16, beta-3 HPV types, and beta-2 HPV38 further highlights the functional similarities of HR HPV16 and beta-3 HPV49, HPV75, and HPV76. The expression profiles of these four HPV HFKs show some similarities and diverge substantially from those of beta-3 HPV115 E6/E7 and beta-2 HPV38 E6/E7 HFKs. In summary, our data show that beta-3 HPV types share some mechanisms with HR HPV types and pave the way for additional studies aiming to evaluate their potential role in human pathologies.IMPORTANCE Human papillomaviruses are currently classified in different genera. Mucosal HPVs belonging to the alpha genus have been clearly associated with carcinogenesis of the mucosal epithelium at different sites. Beta HPV types have been classified as cutaneous. Although findings indicate that some beta HPVs from species 1 and 2 play a role, together with UV irradiation, in skin cancer, very little is known about the transforming properties of most of the beta HPVs. This report shows the transforming activity of E6 and E7 from beta-3 HPV types. Moreover, it highlights that beta-3 HPVs share some biological properties more extensively with mucosal high-risk HPV16 than with beta-2 HPV38. This report provides new paradigms for a better understanding of the biology of the different HPV types and their possible association with lesions at mucosal and/or cutaneous epithelia.

Beta human papillomaviruses infection and skin carcinogenesis

During the last decade, the worldwide incidence of keratinocyte carcinomas (KC) has increased significantly. They are now the most common malignancy, representing approximately 30% of all cancers. The role of ultraviolet (UV) radiation as a major environmental risk factor for skin cancers is well recognized. The aim of this review is to analyse the current understanding of the nature of beta-human papillomavirus (HPV) and its association with KC and explore the implications for the management and prevention of these cancers. A comprehensive review of the literature on beta-HPV and its association with KC was undertaken, the results reported in the form of a narrative review. A subgroup of HPV that infects the mucosal epithelia of the genital tract has been firmly associated with carcinogenesis. In addition, some HPV types with cutaneous tropism have been proposed to cooperate with UV in the development of KC. The first evidence for this association was reported in 1922 in patients with epidermodysplasia verruciformis (EV). Since then, epidemiological studies have highlighted the higher risk of skin cancer in patients with EV and certain cutaneous HPV types, and in vitro studies have elucidated molecular mechanisms and transforming properties of beta-HPV. Furthermore, in vivo research conducted on transgenic mice models has shown the possible role of beta-HPV in cutaneous carcinogenesis as a co-factor with UV radiation and immunosuppression. There is good evidence supporting the role of beta-HPV in the oncogenesis of KC. The high prevalence of beta-HPV in human skin and the worldwide burden of KC makes the search for an effective vaccine relevant and worthwhile.

The Role of Beta HPV Types and HPV-Associated Inflammatory Processes in Cutaneous Squamous Cell Carcinoma

Cutaneous squamous cell carcinoma (cSCC) is a common form of skin cancer with a complex but not fully understood pathogenesis. Recent research suggests the role of beta human papillomavirus (HPV) types and HPV-associated inflammatory processes in cSCC development. Beta HPV types are components of the normal flora; however, under the influence of certain cofactors, the virus may trigger a malignant process. Dysregulation of the immune system (chronic inflammation and immunosuppression), environmental factors (ultraviolet radiation), and genetic factors are the most important cofactors involved in beta HPV-related carcinogenesis. In addition, the oncoproteins E6 and E7 of beta HPV types differ biochemically from their counterparts in the structure of alpha HPV types, resulting in different mechanisms of action in carcinogenesis. The aim of our manuscript is to present an updated point of view on the involvement of beta HPV types in cSCC pathogenesis.

Molecular Profiling of Keratinocyte Skin Tumors Links Staphylococcus aureus Overabundance and Increased Human β-Defensin-2 Expression to Growth Promotion of Squamous Cell Carcinoma

The skin microbiota plays a prominent role in health and disease; however, its contribution to skin tumorigenesis is not well understood. We comparatively assessed the microbial community compositions from excision specimens of the main human non-melanoma skin cancers, actinic keratosis (AK), squamous cell carcinoma (SCC) and basal cell carcinoma (BCC). Keratinocyte skin tumors are characterized by significantly different microbial community compositions, wherein AK and SCC are more similar to each other than to BCC. Notably, in SCC, which represents the advanced tumor entity and frequently develops from AK, overabundance of Staphylococcus aureus, a known skin pathogen, was noted. Moreover, S. aureus overabundance was significantly associated with increased human β-defensin-2 (hBD-2) expression in SCC. By challenging human SCC cell lines with S. aureus, a specific induction of hBD-2 expression and increased tumor cell growth was seen. Increased proliferation was also induced by directly challenging SCC cells with hBD-2. Together, our data indicate that a changed microbial community composition in SCC, specified by S. aureus overabundance, might promote tumor cell growth via modulation of hBD-2 expression.

Viruses in Skin Cancer (VIRUSCAN): Study Design and Baseline Characteristics of a Prospective Clinic-Based Cohort Study

BACKGROUND

Accumulating evidence suggests that cutaneous viral infections are risk factors for the development of keratinocyte carcinomas. The Viruses in Skin Cancer (VIRUSCAN) Study, a prospective cohort study, was established in 2014 to investigate the risk of keratinocyte carcinoma associated with cutaneous human papillomavirus and polyomavirus infection and the possible interaction with ultraviolet radiation exposure (UVR).

METHODS/RESULTS

VIRUSCAN incorporates repeated measures of viral infection using multiple markers of infection and quantitative measures of UVR using a spectrophotometer. Participants were recruited between July 14, 2014 and August 31, 2017 at the University of South Florida Dermatology Clinic in Tampa, FL. After excluding 124 individuals with prevalent keratinocyte carcinomas at baseline, 1,179 participants (53.2% women, 46.8% men, all ages 60 years and older) were followed for up to 4 years with routine skin exams occurring every 6 to 12 months. Here, we present the VIRUSCAN Study design, methods, and baseline characteristics, including demographics, sun exposure behavior, quantitative UVR exposure measurements, and cutaneous viral prevalence, for the full study cohort.

CONCLUSIONS

The VIRUSCAN Study will provide critical temporal evidence needed to assess the causality of the role cutaneous viral infections play in the development of keratinocyte carcinomas, as well as the potential interaction between cutaneous viral infections and UVR exposure.

IMPACT

Study findings will be valuable in future development of novel keratinocyte carcinoma prevention strategies.

Association of Some High-Risk Mucosal Types of Human Papillomavirus with Cutaneous Squamous Cell Carcinoma in an Iranian Population

Background & Objective

Squamous cell carcinoma (SCC) is the second most common non-melanoma skin cancer that may be caused by Human papillomavirus (HPV), especially in immunosuppressed patients. However, the role of the mucosal types of HPV in SCC patients with normal immunity has not been extensively confirmed. The aim of this study was to investigate the association of some high-risk mucosal types of HPV with cutaneous SCC in an Iranian population.

Methods

Sixty-five formalin-fixed, paraffin-embedded tissue specimens with a diagnosis of cutaneous SCC as the case group and sixty-five healthy skin specimens as the control group were included in our case-control study. Genomic DNA was extracted from tissue samples and then PCR was used for the detection of HPV genotypes by a commercial kit.

Results

Our data revealed that 6 out of 65 SCC samples (9.2%) were infected by high-risk mucosal types of HPV whereas none of the 65 control samples were infected by the mentioned HPVs. Statistical analysis showed a significant association between these types of HPV infection and SCC risk in our studied population (P=0.028).

Conclusion

These findings suggested that some high-risk mucosal types of HPV are significant risk factors for cutaneous SCC.

Single-cell RNA sequencing reveals cell type-specific HPV expression in hyperplastic skin lesions

Human Papillomavirus infection is highly prevalent worldwide. While most types of HPV cause benign warts, some high-risk types are known to cause cervical cancer, as well as cancer of the oral cavity and head and neck. Persistent cutaneous HPV infection can be particularly problematic in patients with chronic immunosuppression, for example following organ transplantation. Due to unknown mechanisms, these patients may develop numerous warts, as well as present with a dramatically increased skin cancer prevalence. Despite an association between HPV persistence in the epidermis and excessive wart or squamous cancer development, the molecular mechanisms linking immunosuppression, HPV expression and excessive epidermal proliferation have not been determined, largely due to low-sensitivity methodology to capture rare viral transcription events. Here, we use single-cell RNA sequencing to profile HPV-positive skin lesions from an immunosuppressed patient that were found to express the alphapapillomavirus HPV78 in basal keratinocytes, suprabasal keratinocytes and hair follicle stem cells. This method can be applied to detect and investigate HPV transcripts in cutaneous lesions, allowing mechanistic links between immunosuppression-induced HPV life cycle and epidermal hyperproliferation to be uncovered.

Papillomavirus Immune Evasion Strategies Target the Infected Cell and the Local Immune System

Persistent infection with human papillomavirus (HPV) initiates ~5% of all human cancers, and particularly cervical and oropharyngeal cancers. HPV vaccines prevent HPV infection, but do not eliminate existing HPV infections. Papillomaviruses induce hyperproliferation of epithelial cells. In this review we discuss how hyperproliferation renders epithelial cells less sensitive to immune attack, and impacts upon the efficiency of the local immune system. These observations have significance for the design of therapeutic HPV cancer immunotherapies.

HPV and skin carcinogenesis

Epidemiological and biological studies provide several lines of evidence for the involvement of cutaneous beta human papillomaviruses (HPVs), together with ultraviolet (UV) radiation, in the development of cutaneous squamous cell carcinoma. These viruses appear to act with a hit-and-run mechanism, being necessary at an early stage of carcinogenesis and being dispensable for the maintenance of the malignant phenotype. Studies in experimental models show that beta HPVs, mainly via the E6 and E7 oncoproteins, are able to promote proliferation and to circumvent cellular stresses induced by UV radiation. These findings support a model of skin carcinogenesis in which beta HPV-infected keratinocytes remain alive despite the accumulation of UV-induced DNA mutations. In this manner, these cells become highly susceptible to progression towards malignancy. Thus, UV radiation is the main driver of skin cancer development, while beta HPVs act as facilitators of the accumulation of UV-induced DNA mutations.

Epizootic of multi-centric, squamous cell carcinomas in populations of Indo-Pacific humpbacked dolphins Sousa chinensis in Thai waters

Over the span of several years, 3 Indo-Pacific humpbacked dolphins died and were necropsied in Thailand. These 3 animals were all captive-bred at Oasis Sea World (Chanthaburi, Thailand), and displayed similar macroscopic progressive cutaneous lesions diagnosed as squamous cell carcinomas. In 2 of the 3 animals, necropsy revealed a severe fibrinosuppurative tracheitis and pneumonia secondary to metastasis of a cutaneous squamous cell carcinoma which extended from the head throughout the trunk and flippers. The tumors were characterized by coalescing botryoid masses with severe areas of cutaneous erosion, ulceration and necrohemorrhagic dermatitis. There was evidence of metastasis to the lungs and hilar lymph nodes. Necropsy of the third animal revealed similar progressive cutaneous squamous cell carcinomas but without evidence of metastasis. DNA molecular analysis of homogenized neoplastic tissue was conducted using polymerase chain reaction for both herpesvirus and papillomavirus in 2 of the 3 cases. In the first case, the tissues were positive for a herpesvirus alone, and this was phylogenetically classified as an alphaherpesvirus. This new herpesvirus has been tentatively named Sousa chinensis alphaherpesvirus. The second animal was negative for this novel herpesvirus and the third was not analyzed. In addition to the captive population, there is photographic evidence from 2 separate wild populations of Indo-Pacific humpbacked dolphins in the Gulf of Thailand, of a macroscopically identical proliferative and ulcerative process suspected to be squamous cell carcinomas.

An Emerging Issue in Oncogenic Virology: the Role of Beta Human Papillomavirus Types in the Development of Cutaneous Squamous Cell Carcinoma

Evidence suggests that beta human papillomaviruses (HPVs), together with ultraviolet radiation, contribute to the development of cutaneous squamous cell carcinoma. Beta HPVs appear to be not the main drivers of carcinogenesis but rather facilitators of the accumulation of ultraviolet-induced DNA mutations. Beta HPVs are promoters of skin carcinogenesis, although they are dispensable for the maintenance of the malignant phenotype. Therefore, beta HPV represents a target for skin cancer prevention, especially in high-risk populations.

Classic Vulvar Intraepithelial Neoplasia With Superimposed Lichen Simplex Chronicus: A Unique Variant Mimicking Differentiated Vulvar Intraepithelial Neoplasia

High-grade vulvar intraepithelial neoplasia, a precursor lesion to vulvar squamous cell carcinoma, is subdivided into 2 types, classic or usual vulvar intraepithelial neoplasia (CVIN) and differentiated vulvar intraepithelial neoplasia (DVIN). CVIN, which is a human papilloma virus (HPV)-dependent lesion, is typically distinguished from DVIN, a p53 mutation-dependent process, by its distinct histomorphologic and immunohistochemical characteristics. However, distinguishing between the 2 entities becomes challenging in cases of CVIN with superimposed inflammatory changes, especially lichen simplex chronicus (LSC). Twelve cases of DVIN, 9 cases of LSC, and 9 cases of CVIN with superimposed LSC were assessed for a number of morphologic features, including hyperkeratosis, hypergranulosis, acanthosis, hypercellularity, abnormal maturation (i.e. abnormal keratinization close to the base and/or dyskeratosis), hyperchromasia, and basal atypia. Immunohistochemistry for p53, p16, and MIB-1 was performed for all cases. When sufficient tissue was available, HPV genotyping was performed for cases of CVIN with superimposed LSC. DVIN uniformly demonstrated abnormal maturation, and atypia involving the basal cell layer; they were all p16 negative and demonstrated p53 positivity of moderate to strong intensity in a basal and parabasal distribution. CVIN with superimposed LSC frequently displayed hyperchromasia involving the basal 3 to 4 cell layers, basal to full-thickness atypia, and apoptosis. CVIN with superimposed LSC demonstrated intense p16 positivity extending from the basal cells to the mid-epithelium and a reduction or loss of staining in maturing keratinocytes. P53 staining revealed a unique pattern of parabasal and mid-epithelial weak to moderate staining with sparing of the basal layer. Cases of LSC demonstrated heterogenous p53 positivity and were negative for p16. MIB-1 staining showed a similar range of positivity for all diagnoses. HPV genotyping revealed HPV 16 in all 5 cases of CVIN with LSC that underwent testing. We conclude that, although CVIN with superimposed LSC can closely resemble DVIN, morphologic features such as nuclear hyperchromasia uniformly involving the basal 3 to 4 cell layers, apoptosis, and absent or less pronounced cytoplasmic maturation are more suggestive of CVIN with superimposed LSC. In cases where the morphology remains ambiguous, immunohistochemistry for both p16 and p53 can be helpful. In particular, p53 parabasal and mid-epithelial staining without involvement of the basal layer appears to be a characteristic finding in CVIN with superimposed LSC. MIB-1 staining is of little utility in distinguishing between these entities and should not be routinely performed.

Beta Human Papillomavirus and Associated Diseases

The cutaneous human papillomavirus (HPV), mostly from β- and γ-HPV genus, is ubiquitously distributed throughout the human body and may be part of the commensal flora. The association of β-HPVs and cutaneous squamous cell carcinoma (cSCC) development was initially reported in patients with the rare genetic disorder Epidermodysplasia verruciformis. Likewise, immunosuppressed organ transplant recipients have an increased susceptibility to β-HPV infections in the skin as well as to cSCC development. Although ultraviolet radiation (UVR) is the main risk factor of cSCC, experimental data points toward β-HPVs as co-carcinogens, which appear to be required solely at early stages of skin carcinogenesis by facilitating the accumulation of UVR-induced DNA mutations. Several epidemiological studies relying on different biomarkers of β-HPV infections have also been conducted in immunocompetent individuals to access their association with cSCC development. Additionally, in vivo and in vitro studies are presenting cumulative evidence that E6 and E7 proteins from specific β-HPVs exhibit transforming activities and may collaborate with different environmental factors in promoting carcinogenesis. Nevertheless, further research is crucial to better understand the pathological implications of the broad distribution of these HPVs.

Epidemiology and biology of cutaneous human papillomavirus

Cutaneous human papillomaviruses (HPVs) include β- and γ-HPVs, in addition to a small fraction of α-HPVs. β-HPVs were first isolated from patients with the rare genetic disorder Epidermodysplasia verruciformis, and they are associated with the development of nonmelanoma skin cancer at sun-exposed skin sites in these individuals. Organ transplant recipients also have greater susceptibility to β-HPV infection of the skin and an increased risk of developing nonmelanoma skin cancer. In both immunosuppressed and immunocompromised individuals, cutaneous HPVs are ubiquitously disseminated throughout healthy skin and may be an intrinsic part of the commensal flora. Functional analysis of E6 and E7 proteins of specific cutaneous HPVs has provided a mechanistic comprehension of how these viruses may induce carcinogenesis. Nevertheless, additional research is crucial to better understand the pathological implications of the broad distribution of these HPVs.

Metastatic squamous cell carcinoma of known and unknown primary origin treated with axillary or inguinal lymphadenectomy

BACKGROUND

Metastatic squamous cell carcinoma (SCC) to the axillary or inguinal lymph nodes from an unknown primary source is rarely encountered. We sought to evaluate a cohort of patients with metastatic SCC managed by lymphadenectomy to determine their survival and to determine which clinicopathologic factors were associated with outcome.

METHODS

All patients undergoing axillary or inguinal lymphadenectomy for SCC at our institution were identified retrospectively. Patients were stratified by unknown primary (UP) vs known skin primary (KP) tumors. Pertinent data on patient, tumor, and treatment variables was collected.

RESULTS

We identified 51 patients who met inclusion criteria. Of those, 20 patients (39%) had UP metastatic SCC and 31 patients (61%) had KP. The 5-year overall survival for UP was 65%, as compared to 49% for KP (p = 0.16). Cumulative incidence of recurrence was 46%. Cox regression failed to demonstrate a significant association between KP vs UP, HPV status, chemotherapy, or radiation with survival.

CONCLUSIONS

Nearly two-thirds of patients undergoing axillary or inguinal lymphadenectomy for metastatic SCC of unknown primary were alive five years following the procedure.

Beta and gamma human papillomaviruses in anal and genital sites among men: prevalence and determinants

Data regarding the anogenital distribution of and type-specific concordance for cutaneous β- and γ-HPV types in men who have sex with women is limited and geographically narrow. Knowledge of determinants of anogenital detection of cutaneous HPV types in different regions is needed for better understanding of the natural history and transmission dynamics of HPV, and its potential role in the development of anogenital diseases. Genital and anal canal samples obtained from 554 Russian men were screened for 43 β-HPVs and 29 γ-HPVs, using a multiplex PCR combined with Luminex technology. Both β- and γ-HPVs were more prevalent in the anal (22.8% and 14.1%) samples than in the genital (16.8% and 12.3%) samples. Low overall and type-specific concordance for β-HPVs (3.5% and 1.1%) and γ-HPVs (1.3% and 0.6%) were observed between genital and anal samples. HIV-positive men had higher anal β- (crude OR = 12.2, 95% CI: 5.3–28.1) and γ-HPV (crude OR = 7.2, 95% CI: 3.3–15.4) prevalence than HIV-negative men. Due to the lack of genital samples from the HIV-positive men, no comparison was possible for HIV status in genital samples. The lack of type-specific positive concordance between genital and anal sites for cutaneous β- and γ-HPV types in heterosexual men posits the needs for further studies on transmission routes to discriminate between contamination and true HPV infection. HIV-positive status may favor the anal acquisition or modify the natural history of cutaneous HPV types.

Detection of novel Betapapillomaviruses and Gammapapillomaviruses in eyebrow hair follicles using a single-tube 'hanging droplet' PCR assay with modified pan-PV CODEHOP primers

A modified pan-PV consensus-degenerate hybrid oligonucleotide primer (CODEHOP) PCR was developed for generic and sensitive detection of a broad-spectrum of human papillomaviruses (HPVs) infecting the cutaneous epithelium. To test the analytical sensitivity of the assay we examined 149 eyebrow hair follicle specimens from immunocompetent male patients. HPV DNA was detected in 60 % (89/149) of analysed eyebrow samples with a total of 48 different HPV sequences, representing 21 previously described HPVs and 27 putative novel HPV types. Evidence for ten novel HPV subtypes and seven viral variants, clustering to three out of five genera containing cutaneous HPVs, was also obtained. Thus, we have shown that the modified pan-PV CODEHOP PCR assay is able to identify multiple HPV types, even from different genera, in the same clinical sample. Overall, these results demonstrate that the pan-PV CODEHOP PCR is an excellent tool for screening and identification of novel cutaneous HPVs, even in samples with low viral loads.

Loss of Genome Fidelity: Beta HPVs and the DNA Damage Response

While the role of genus alpha human papillomaviruses in the tumorigenesis and tumor maintenance of anogenital and oropharyngeal cancers is well-established, the role of genus beta human papilloviruses (β-HPVs) in non-melanoma skin cancers (NMSCs) is less certain. Persistent β-HPV infections cause NMSCs in sun-exposed skin of people with a rare genetic disorder, epidermodysplasia verruciformis. However, β-HPV infections in people without epidermodysplasia verruciformis are typically transient. Further, β-HPV gene expression is not necessary for tumor maintenance in the general population as on average there is fewer than one copy of the β-HPV genome per cell in NMSC tumor biopsies. Cell culture, epidemiological, and mouse model experiments support a role for β-HPV infections in the initiation of NMSCs through a "hit and run" mechanism. The virus is hypothesized to act as a cofactor, augmenting the genome destabilizing effects of UV. Supporting this idea, two β-HPV proteins (β-HPV E6 and E7) disrupt the cellular response to UV exposure and other genome destabilizing events by abrogating DNA repair and deregulating cell cycle progression. The aberrant damage response increases the likelihood of oncogenic mutations capable of driving tumorigenesis independent of a sustained β-HPV infection or continued viral protein expression. This review summarizes what is currently known about the deleterious effects of β-HPV on genome maintenance in the context of the virus's putative role in NMSC initiation.

Prevalence and Concordance of Cutaneous Beta Human Papillomavirus Infection at Mucosal and Cutaneous Sites

Background

Cutaneous beta human papillomavirus (HPV) infection across cutaneous and mucosal tissues within individuals has not been examined.

Methods

A subcohort of men (n = 87) participating in the HPV Infection in Men (HIM) study provided eyebrow hairs, forearm skin swabs, genital skin swabs, oral rinse samples, and anal swabs. Beta-HPV DNA in the 5 tissues was detected using a multiplex assay, and site-specific beta-HPV prevalence was examined.

Results

Any beta-HPV was most prevalent in genital skin (81.6%), followed by forearm skin (64.4%), eyebrow hairs (60.9%), oral mucosa (35.6%), and anal mucosa (33.3%). Most prevalent beta-HPV types included HPV-38 (beta-2) in both genital skin (32.2%) and eyebrow hairs (16.1%), HPV-12 (beta-1) in forearm skin (23%) and oral mucosa (9.2%), and HPV-76 (beta-3) in anal mucosa (14.9%). Concordance of any beta-HPV infection was greater (31.0%) across the 3 keratinized tissue sites (genital skin, eyebrow hairs, forearm skin) than across the 2 mucosal sites (anal and oral mucosa, 6.9%).

Conclusions

Prevalence of beta-HPV varied by anatomic site of infection. Biological properties of beta-HPV types detected at mucosal sites and their role in disease pathogenesis should be examined.

Risk of cancer in patients with genital warts: A nationwide, population-based cohort study in Taiwan

Background

Condyloma acuminata currently affects around 1% of sexually active adults, and its incidence is increasing. The coexistence of genital warts (GW) and certain cancers and an association between human papillomavirus (HPV) and various malignancies have been reported. Therefore, we conducted this large national study to analyze the risk of malignancies among men and women with GW in Taiwan.

Methods and findings

Between January 2000 and December 2013, approximately 3 million patients were reported to the National Health Insurance Research Database of Taiwan. Of these patients, 21,763 were diagnosed with GW. In the same time period, a total of 213,541 cancer cases were reported to the registry, of which 1002 were recorded among patients with GW. The age-specific incidence rates of GW and standardized incidence ratios (SIRs) of malignancies compared to the general population were calculated. Women acquired GW earlier than men, with a mean age at diagnosis of 32.63±12.78 years. The highest incidence rate for both genders peaked at 20–29 years. Of the 1002 patients with GW and malignancies, the SIR was 1.95 (95%CI 1.83–2.07). The most markedly increased risk was found for HPV-related cancers, with a SIR of 9.74 (95%CI 3.70–15.77). Significantly elevated risks were also noted for smoking-related cancers, anogenital cancers, cervix in situ, colon, rectum, lung, kidney, and prostate cancers. Most cancers developed within 10 years after the diagnosis of GW.

Conclusions

Patients with GW have an increased risk of HPV-related cancers, especially anogenital malignancies in Taiwan. The elevated risk of other cancers highlights differences in exposure and risk factors among patients with GW compared to the general population. Cancer screening and HPV vaccination programs should be emphasized for at-risk patients.

Malignant skin tumors: Kids are not just little people

Skin tumors are a clinically heterogeneous group of dermatologic conditions that affect both children and adults. Although similar types of skin tumors can affect both children and adults, the epidemiology, pathogenesis, and treatment of these skin neoplasms can vary drastically in children compared with adults. Despite the clear need for literature elucidating the differences of skin tumors in children compared with adults, there is a serious dearth of scientific contributions addressing this area. This contribution highlights the types of differences that can occur between adults and children with skin neoplasms, as well as the special considerations that need to be recognized when managing skin tumors in children by providing a comparative analysis of basal cell carcinoma, squamous cell carcinoma, and Kaposi sarcoma occurring in adults with these same tumors occurring in children. Specifically, we examine the aforementioned tumors with a focus on (1) epidemiology, (2) etiology, (3) clinical presentation, (4) workup, and (5) treatment.

Human papillomaviruses and carcinogenesis: well-established and novel models

Human papillomaviruses (HPVs) infect the cutaneous or mucosal epithelia and are classified phylogenetically as genera and species. Persistent infections by the mucosal high-risk (HR) HPV types from genus alpha are associated with cancer development of the genital and upper respiratory tracts. The products of two early genes, E6 and E7, are the major HR HPV oncoproteins, being essential in all steps of the carcinogenic process. Cutaneous beta HPV types are proposed, together with ultraviolet (UV) radiation, to promote non-melanoma skin cancer development. However, in contrast to the HR HPV types, beta HPV types appear to be required only at an early stage of carcinogenesis, facilitating the accumulation of UV-induced DNA mutations. Although findings in experimental models also suggest that beta HPV types and other carcinogens may synergize in the induction of malignancies, these possibilities need to be confirmed in human studies.

Natural history of human papillomavirus infection of sun-exposed healthy skin of immunocompetent individuals over three climatic seasons and identification of HPV209, a novel betapapillomavirus

We present the first longitudinal study reporting the natural history of human papillomavirus (HPV) infection in sun-exposed skin of healthy individuals living in a geographical area in which solar UV radiation is influenced by the ozone content of the atmosphere. During three climatic seasons, skin swab samples were obtained from 78 healthy individuals and the prevalence of cutaneous HPVs was assessed with broad-spectrum FAP and CUT primers and determined at 54, 45 and 47 % in spring, summer and winter, respectively. Frequencies of mixed HPV infections were significantly higher in spring with respect to summer and winter (P=0.02). Seventy-one different HPV types/putative types were identified. While 62 volunteers were HPV-infected in at least one season, 23 had persistent infections. β-PVs (β-1) were the most prevalent and persistent. Age was associated with both the infection status (P=0.01) and the type of HPV infection (no infection, indeterminate/transient, persistent P=0.02). The molecular/phylogenetic analysis of the newly identified β-PV, officially designated as HPV209, showed that the virus has a typical genomic organization of cutaneous HPVs with five early (E6, E7, E1, E2 and E4) and two late genes (L2 and L1), which clusters to the species β-2. This provides useful data on cutaneous HPV infections in high UV-exposed regions.

Ovis aries Papillomavirus 3 in Ovine Cutaneous Squamous Cell Carcinoma

Squamous cell carcinoma (SCC) is a common malignancy affecting humans and other animals. Papillomaviruses (PVs) are frequently reported as causal agents of cutaneous benign and malignant epithelial lesions in different animal species, but only few studies have investigated their role in ovine SCC. In this study, we explore the possible involvement of the Ovine aries PVs (OaPV1, OaPV2, OaPV3) in cutaneous SCC using an integrated histological and molecular approach. Forty cutaneous SCCs from different anatomical locations of Sardinian sheep and 40 matched non-SCC samples were evaluated histologically and by polymerase chain reaction (PCR) to assess the presence of ovine PVs. In addition, DNA in situ hybridization (ISH) and reverse transcription-polymerase chain reaction (RT-PCR) were carried out to evaluate the cellular localization and viral transcriptional activity, respectively. OaPV3 DNA was detected in 26 of 40 (65%) SCCs and in 12 of 40 (30%) non-SCC samples using PCR. OaPV1 and OaPV2 were not detected. OaPV3 viral DNA was observed by ISH in malignant epithelial squamous cells of 18 of 40 (45%) SCCs. In addition, the viral transcriptional activity was identified in 24 of 40 (60%) SCCs by RT-PCR. Notably, a higher viral positivity was observed in SCCs compared with non-SCC samples. The considerable infection rate of OaPV3 in the most common skin tumor of the sheep suggests that PV could represent a key factor in the onset of ovine SCC.

The biology of beta human papillomaviruses

The beta genus comprises more than 50 beta human papillomavirus (HPV) types that are suspected to be involved, together with ultraviolet (UV) irradiation, in the development of non-melanoma skin cancer (NMSC), the most common form of human cancer. Two members of the genus beta, HPV5 and HPV8, were first identified in patients with a genetic disorder, epidermodysplasia verruciformis (EV), that confers high susceptibility to beta HPV infection and NMSC development. The fact that organ transplant recipients (OTRs) with an impaired immune system have an elevated risk of NMSC raised the hypothesis that beta HPV types may also be involved in skin carcinogenesis in non-EV patients. Epidemiological studies have shown that serological and viral DNA markers are weakly, but significantly, associated with history of NMSC in OTRs and the general population. Functional studies on mucosal high-risk (HR) HPV types have clearly demonstrated that the products of two early genes, E6 and E7, are the main viral oncoproteins, which are able to deregulate events closely linked to transformation, such as cell cycle progression and apoptosis. Studies on a small number of beta HPV types have shown that their E6 and E7 oncoproteins also have the ability to interfere with the regulation of key pathways/events associated with cellular transformation. However, the initial functional data indicate that the molecular mechanisms leading to cellular transformation are different from those of mucosal HR HPV types. Beta HPV types may act only at early stages of carcinogenesis, by potentiating the deleterious effects of other carcinogens, such as UV radiation.

The low-risk papillomaviruses

Human Papillomavirus (HPV) research has been dominated by the study of a subset of Alpha papillomaviruses that together cause almost 5% of human cancers worldwide, with the focus being on the two most prominent of these (HPV16 and 18). These viruses are referred to as 'high-risk' (hrHPV), to distinguish them from the over 200 prevalent HPV types that more commonly cause only benign epithelial lesions. The 'low-risk' (lrHPV) term used to describe this group belies their cumulative morbidity. Persistent laryngeal papillomas, which occur rarely in children and adults, require regular surgical de-bulking to allow breathing. Such infections are not curable, and despite being caused by HPV11 (a lrHPV) are associated with 1-3% risk of cancer progression if not resolved. Similarly, the ubiquitous Beta HPV types, which commonly cause asymptomatic infections at cutaneous sites, can sometimes cause debilitating papillomatosis with associated cancer risk. Recalcitrant genital warts, which affect 1 in 200 young adults in the general population, and even the ubiquitous common warts and verrucas that most of us at some time experience, cannot be reliably eradicated, with treatment strategies advancing little over the last 100 years. The review highlights molecular similarities between high and low-risk HPV types, and focuses on the different pathways that the two groups use to ensure persistent infection and adequate virus shedding from the epithelial surface. Understanding the normal patterns of viral gene expression that underlie lesion formation, and which also prevent loss of the infected basal cells in established lesions, are particularly important when considering new treatment options. Finally, the common requirement for deregulated viral gene expression and genome persistence in development of cancers, unites both high and low-risk HPV types, and when considered alongside viral protein functions, provides us with a working understanding of the mechanisms that underlie HPV-associated pathology.

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.

Associations of Oral α-, β-, and γ-Human Papillomavirus Types With Risk of Incident Head and Neck Cancer

Importance

Prospective studies are needed to examine the temporal relationship between oral human papillomavirus (HPV) detection and risk of head and neck squamous cell carcinoma (HNSCC). Moreover, the oral cavity contains a wide spectrum of α-, β-, and γ-HPV types, but their association with risk of HNSCC is unknown.

Objective

To prospectively examine associations between α-, β-, and γ-HPV detection in the oral cavity and incident HNSCC.

Design

A nested case-control study was carried out among 96 650 participants, cancer free at baseline, with available mouthwash samples in 2 prospective cohort studies: (1) the American Cancer Society Cancer Prevention Study II Nutrition Cohort and (2) the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial. Incident cases of HNSCC (n = 132) were identified during an average 3.9 years of follow-up in both cohorts. Three controls per case (n = 396) were selected through incidence density sampling and matched on age, sex, race/ethnicity, and time since mouthwash collection.

Methods

Through a next-generation sequencing assay, DNA from α-, β-, and γ-HPV types were detected. Conditional logistic regression models were used to estimate odds ratios (ORs) and 95% CIs, adjusting for smoking history, alcohol consumption, and detection of HPV-16 for β- and γ-HPVs.

Main Outcomes and Measures

Incident HNSCC, which includes cancers of the oropharynx, oral cavity, and larynx.

Results

A total of 132 participants developed HNSCC during the follow-up period (103 men and 29 women; average age at baseline, 66.5 years). Oral HPV-16 detection was associated with incident HNSCC (OR, 7.1; 95% CI, 2.2-22.6), with positive association for oropharyngeal SCC (OR, 22.4; 95% CI, 1.8-276.7), but not for oral cavity (OR, 4.5; 95% CI, 0.6-34.7) or laryngeal SCCs (OR, 0.11; 95% CI, 0.01-834.80). Detection of β1-HPV-5 and β2-HPV-38 types, as well as γ-11 and γ-12 species, had ORs for HNSCC that ranged from 2.64 to 5.45 (P < .01 for all comparisons). Detection of β1-HPV-5 type was associated with oropharyngeal (OR, 7.42; 95% CI, 0.98-56.82; P = .054), oral cavity (OR, 5.34; 95% CI, 1.51-18.80; P = .01), and laryngeal SCCs (OR, 2.71; 95% CI, 1.00-7.43; P = .05), whereas γ11- and γ12-HPV species were associated with both oral cavity (OR, 7.47; 95% CI, 1.21-46.17; P = .03; and OR, 6.71; 95% CI, 1.47-30.75; P = .01, respectively) and laryngeal SCCs (OR, 7.49; 95% CI, 1.10-51.04; P = .04 and OR, 5.31; 95% CI, 1.13-24.95; P = .03, respectively).

Conclusions and Relevance

This study demonstrates that HPV-16 detection precedes the incidence of oropharyngeal SCC. Associations of other HPVs, including γ11- and γ12-HPV species and β1-HPV-5 type suggest a broader role for HPVs in HNSCC etiology.

Characterization of novel human papillomavirus types 157, 158 and 205 from healthy skin and recombination analysis in genus γ-Papillomavirus

Gammapapillomavirus (γ-PV) is a diverse and rapidly expanding genus, currently consisting of 79 fully characterized human PV (HPV) types. In this study, three novel types, HPV157, HPV158 and HPV205, obtained from healthy sun-exposed skin of two immunocompetent individuals, were amplified by the "Hanging droplet" long PCR technique, cloned, sequenced and characterized. HPV157, HPV158 and HPV205 genomes comprise 7154-bp, 7192-bp and 7298-bp, respectively, and contain four early (E1, E2, E6 and E7) and two late genes (L1 and L2). Phylogenetic analysis of the L1 ORF placed all novel types within the γ-PV genus: HPV157 was classified as a new member of species γ-12 while HPV158 and HPV205 belong to species γ-1. We then explored potential recombination events in genus γ-PV with the RDP4 program in a dataset of 74 viruses (71 HPV types with available full-length genomes and the 3 novel types). Two events, both located in the E1 ORF, met the inclusion criterion (p-values <0.05 with at least four methods) and persisted in different ORF combinations: an inter-species recombination in species γ-8 (major and minor parents: species γ-24 and γ-11, respectively), and an intra-species recombination in species γ-7 (recombinant strain: HPV170; major and minor parents: HPV-109 and HPV-149, respectively). These findings were confirmed by phylogenetic tree incongruence analysis. An additional incongruence was found in members of species γ-9 but it was not detected by the RDP4. This report expands our knowledge of the family Papillomaviridae and provides for the first time in silico evidence of recombination in genus γ-PV.

Human papillomavirus molecular biology and disease association

Human papillomaviruses (HPVs) have evolved over millions of years to propagate themselves in a range of different animal species including humans. Viruses that have co‐evolved slowly in this way typically cause chronic inapparent infections, with virion production in the absence of apparent disease. This is the case for many Beta and Gamma HPV types. The Alpha papillomavirus types have however evolved immunoevasion strategies that allow them to cause persistent visible papillomas. These viruses activate the cell cycle as the infected epithelial cell differentiates in order to create a replication competent environment that allows viral genome amplification and packaging into infectious particles. This is mediated by the viral E6, E7, and E5 proteins. High‐risk E6 and E7 proteins differ from their low‐risk counterparts however in being able to drive cell cycle entry in the upper epithelial layers and also to stimulate cell proliferation in the basal and parabasal layers. Deregulated expression of these cell cycle regulators underlies neoplasia and the eventual progression to cancer in individuals who cannot resolve high‐risk HPV infection. Most work to date has focused on the study of high‐risk HPV types such as HPV 16 and 18, which has led to an understanding of the molecular pathways subverted by these viruses. Such approaches will lead to the development of better strategies for disease treatment, including targeted antivirals and immunotherapeutics. Priorities are now focused toward understanding HPV neoplasias at sites other than the cervix (e.g. tonsils, other transformation zones) and toward understanding the mechanisms by which low‐risk HPV types can sometimes give rise to papillomatosis and under certain situations even cancers. Copyright © 2015 John Wiley & Sons, Ltd.

No Evidence of Human Papilloma Virus Infection in Basal Cell Carcinoma

Background:

Basal cell carcinoma (BCC) is the most common skin cancer among whites, and several risk factors have been discussed in itsdevelopment and progress. Detection of human papilloma virus (HPV) deoxyribonucleic acid (DNA) BCCs in some studies suggests that the virus may play a role in the pathogenesis of this disease. Several molecular studies showed conflicting reports.

Aims:

The purpose of this study was to investigate the association between HPV and BCC using polymerase chain reaction (PCR).

Materials and Methods:

HPV DNA detection was done for 42 paraffin-embedded tissue specimens of BCC and 42 normal skin samples around the lesions by PCR using GP5+/GP6+ primers.

Results:

HPV DNA was not found in any of the 42 samples of BCC, and only one normal skin sample around the lesions was positive for HPV DNA by PCR.

Conclusion:

In this study, no statistically significant difference was seen between the presence of HPV DNA in BCC and normal skin around the lesion, and HPV is not likely to have an important role in pathogenesis of BCC.

Cancer, Warts, or Asymptomatic Infections: Clinical Presentation Matches Codon Usage Preferences in Human Papillomaviruses

Viruses rely completely on the hosts’ machinery for translation of viral transcripts. However, for most viruses infecting humans, codon usage preferences (CUPrefs) do not match those of the host. Human papillomaviruses (HPVs) are a showcase to tackle this paradox: they present a large genotypic diversity and a broad range of phenotypic presentations, from asymptomatic infections to productive lesions and cancer. By applying phylogenetic inference and dimensionality reduction methods, we demonstrate first that genes in HPVs are poorly adapted to the average human CUPrefs, the only exception being capsid genes in viruses causing productive lesions. Phylogenetic relationships between HPVs explained only a small proportion of CUPrefs variation. Instead, the most important explanatory factor for viral CUPrefs was infection phenotype, as orthologous genes in viruses with similar clinical presentation displayed similar CUPrefs. Moreover, viral genes with similar spatiotemporal expression patterns also showed similar CUPrefs. Our results suggest that CUPrefs in HPVs reflect either variations in the mutation bias or differential selection pressures depending on the clinical presentation and expression timing. We propose that poor viral CUPrefs may be central to a trade-off between strong viral gene expression and the potential for eliciting protective immune response.

Alpha, beta and gamma Human Papillomaviruses in the anal canal of HIV-infected and uninfected men who have sex with men

OBJECTIVES

Anal infection by cutaneous Human Papillomaviruses (HPV) has been rarely investigated. We aimed to assess the prevalence, genotype diversity, and determinants of mucosal (alpha) and cutaneous (beta and gamma) anal HPV infection in men who have sex with men (MSM).

METHODS

Anal samples were collected with a Dacron swab. Alpha HPVs were detected using the Linear Array HPV genotyping test, while beta and gamma HPVs using a PCR combined with Luminex technology.

RESULTS

A total of 609 MSM (437 HIV-uninfected and 172 HIV-infected, most of which were undergoing cART) were enrolled. Alpha, beta, and gamma HPVs were detected in 78.0%, 27.6% and 29.3% of the participants. Only alpha HPV prevalence was significantly higher among HIV-infected compared to uninfected MSM (93.0% vs. 72.1%, p < 0.0001). Beta2 and gamma10 represented the most frequent cutaneous HPV species, with no significant differences between HIV-infected and uninfected individuals. The most common alpha, beta, and gamma genotypes were HPV16, HPV111, HPV121, respectively. Alpha HPV infection was significantly associated with lifetime number of partners, receptive anal sex, and HIV status. Beta and/or gamma HPV infection showed no significant association with HIV status, socio-demographic or sexual behavioral factors.

CONCLUSIONS

A wide spectrum of mucosal and cutaneous HPV types is present in the anal canal. Only mucosal HPV prevalence increased significantly in cases of concomitant HIV infection.

Prevalence of beta and gamma human papillomaviruses in the anal canal of men who have sex with men is influenced by HIV status

BACKGROUND

Mucosal high-risk human papillomavirus (HPV) types benefit differently from the immunocompromised status of the host. So far it is not known whether a similar scenario holds for the large group of the β and γ cutaneous HPV types that appear to be present at several anatomical sites.

METHODS

The presence of β (n=43) and γ (n=30) HPVs in the anal samples of 66 HIV-positive and 153 HIV-negative anonymized men who have sex with men (MSM) was determined by multiplex PCR, using type-specific primers and bead-based hybridization (Luminex technology).

RESULTS

The prevalence of β and γ HPV infection was 65.6% and 68.2%, respectively, among HIV-positive MSM and 59.1% and 57.7%, respectively, among HIV-negative MSM. β-2 and γ-10 were found to be the most prevalent species in both groups. The prevalence of infection with HPV types of the species β-1 (P=0.02), β-3 (P=0.002), γ-6 (P=0.002), and γ-7 (P=0.02) was higher in HIV-positive than HIV-negative men. In contrast, the β-2 species was equally distributed in the two groups, while the γ-10 species was slightly affected by HIV status.

CONCLUSIONS

These findings provide evidence that impairment of the host's immune surveillance impacts β and γ HPV infections differently.