Association between epidermodysplasia verruciformis-associated human papillomavirus DNA in plucked eyebrow hair and solar keratoses

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.

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.

[Low-dose prophylactic oral isotretinoin treatment for 18 years in a patient with epidermodysplasia verruciformis and numerous squamous cell carcinomas]

Epidermodysplasia verruciformis (also known as Lewandowsky-Lutz dysplasia) is an extremely rare autosomal recessive genodermatosis, in which the skin is unusually sensitive to human papilloma viruses (HPV). It is associated with a high risk of developing non-melanocytic skin tumors. Treatment with keratolytic retinoids is currently considered to be the most effective therapy. Retinoids have a broad spectrum of activity and inhibit the growth of squamous cell carcinoma and other malignant tumors. We report the case of an 81-year-old woman who had been receiving prophylactic treatment with oral isotretinoin at a daily dose of 1.0-0.33 mg/kg bodyweight for about 18 years because of her epidermodysplasia verruciformis (HPV types 9 & 57 detected). We observed a reduction of the incidence of squamous cell carcinomas of the skin and presume a causal relationship between the treatment with this retinoid and the reduction of squamous cell carcinomas of the skin in this patient.

Seroprevalence of cutaneous human papillomaviruses (HPVs) among men in the multinational HPV Infection in Men study

Data on cutaneous human papillomavirus (HPV) seroprevalence are primarily derived from skin cancer case-control studies. Few studies have reported the seroprevalence of cutaneous HPV among healthy men. This study investigated the seroprevalence of cutaneous HPV types and associated risk factors among men residing in Brazil, Mexico and the USA. Six hundred men were randomly selected from the HPV Infection in Men study. Archived serum specimens were tested for antibodies against 14 cutaneous HPV genotypes, β-HPV types (5/8/12/14/17/22/23/24/38/48), α-HPV 27, γ-HPV 4, µ-HPV1 and ν-HPV 41 using a glutathione S-transferase L1-based multiplex serology assay. Risk factor data were collected by a questionnaire. Binomial proportions were used to estimate seroprevalence, and logistic regression to examine factors associated with seropositivity. Overall, 65.4 % of men were seropositive to ≥1 of the 14 cutaneous HPV types, and 39.0 % were positive for ≥1 β-HPV types. Seroprevalence was 8.9, 30.9, 28.6 and 9.4 % for α-HPV 27, γ-HPV 4, µ-HPV 1 and ν-HPV 41, respectively. In multivariate analyses, seropositivity for any cutaneous HPV type was associated with higher education [adjusted odds ratio (AOR) 1.75; 95 % confidence interval (CI) 1.08-2.83], and seropositivity of any β-HPV type was significantly associated with increasing age (AOR 1.72; 95 % CI 1.12-2.63, for men aged 31-44 years vs men aged 18-30 years). Other factors associated with various type-specific cutaneous HPV seropositivity included country, circumcision and lifetime number of male sexual partners. These data indicate that exposure to cutaneous HPV is common. Future studies are needed to assess the role of cutaneous HPV in diseases.

Equine Genital Squamous Cell Carcinoma: In Situ Hybridization Identifies a Distinct Subset Containing Equus caballus Papillomavirus 2

Equus caballus papillomavirus 2 (EcPV2) has been proposed as an etiologic agent for genital squamous cell carcinoma (SCC), the most common malignant tumor of the horse penis. EcPV2 is commonly detected by polymerase chain reaction (PCR) on normal horse genitalia; therefore, unraveling the virus' role in oncogenic transformation requires other methods of detection. In this study, a highly sensitive multiple-probe chromogenic in situ hybridization (ISH) technique was designed to recognize the E6/E7 oncogenes of EcPV2. ISH demonstrated abundant virus within 6 of 13 penile and preputial SCCs, whereas evidence of solar damage was found in 6 cases that were negative for EcPV2 by ISH. The ISH technique is valuable for studies of pathogenesis, since it demonstrates for the first time that the vast majority of neoplastic cells contain virus. Moreover, hybridization was present in all metastases examined, implying stability of E6/E7 expression in these clonal populations of neoplastic cells. This study contributes to the accumulating evidence for a causal role of EcPV2 in a subset of genital SCCs in horses.

Morphological Spectrum of Orbitoocular Diseases in a Tertiary Health Centre in Keffi, North Central Nigeria

Aim. The aim of this study was to carry out a retrospective clinicopathological analysis of the ocular lesions requiring biopsy seen in the Department of Histopathology, Federal Medical Centre (FMC), Keffi, in North Central Nigeria. Materials and Method. A retrospective review of the clinicopathologic profile of orbitoocular lesions diagnosed at the FMC, Keffi, was done. Clinical and pathological data were obtained from the patients' clinical records and original biopsy reports, respectively. Results. Sixty-six cases of orbitoocular lesions were reviewed for this study. Of the 54 cases investigated, 28 were HIV negative while 26 were HIV positive (37.1% of all cases). There were 30 cases of Ocular Surface Squamous Neoplasia (OSSN) with a male-to-female ratio of 0.9 : 1. Squamous cell carcinoma (SCC) was the most frequent OSSN with 17 cases. The mean age of cases of SCC is 37.1 ± 7.6 SD (years). The mean age of carcinoma in situ is 35.8 ± 11.4 years. Conclusion. There was no significant difference in the sex distribution of patients with OSSN. It is probable that a diagnosis of squamous cell carcinoma may be encountered in about a year after diagnosis of a carcinoma in situ especially if the in situ carcinoma is left untreated or improperly treated.

Human papillomavirus load in eyebrow hair follicles and risk of cutaneous squamous cell carcinoma

BACKGROUND

Beta-human papillomavirus (betaPV) may play a role in the development of cutaneous squamous cell carcinoma (SCC). However betaPV is highly prevalent, and it may only be people with a higher viral load who have increased risk of SCCs. We therefore examined the association between betaPV load and SCCs.

METHODS

We recruited 448 immunocompetent cases with SCCs and 464 controls from Italy and Australia and 497 immunosuppressed organ transplant recipients (OTR; 179 cases and 318 controls) from Europe. We used reverse hybridization to genotype 25 betaPV types in eyebrow hair follicles and determined the viral load for eight selected types using quantitative PCR. We used logistic regression to assess associations between type-specific and cumulative viral load and SCCs.

RESULTS

Australian and OTR participants in the highest cumulative load tertile were at significantly higher risk of SCCs than those in the lowest tertile. Those with more than four betaPV types in the high load tertile were at approximately three-fold increased risk of SCCs. In Australia, HPV23 and 36 loads were significantly associated with SCCs, with borderline associations for HPV5 and 38. In OTR, HPV8 and 38 loads were significantly associated and HPV20 and 36 were borderline. We found little evidence for an association between load and SCCs in Italy.

CONCLUSIONS

High viral load may be associated with risk of cutaneous SCCs, with total load seemingly more important than the load of any specific type.

IMPACT

Our findings lend weight to the hypothesis that HPV plays a role in skin carcinogenesis.

Myrmecia wart inclusions as an incidental histopathologic finding

BACKGROUND

Latent infection by human papillomavirus (HPV) has been described for genital (mucosal) and epidermodysplasia verruciformis subtypes. Only rarely has cutaneotropic, non-oncogenic HPV been found by polymerase chain reaction studies in normal skin.

METHODS

We noted myrmecia wart inclusions as an incidental histopathologic finding in four specimens from diverse sites (eyebrow, scalp, forehead, leg). The final diagnoses for these four cases were intradermal nevus, scarring alopecia, benign keratosis and stasis dermatitis. Anti-HPV antibody staining was performed in all cases. This antibody detects HPV-1,6,11,16,18 and 31 in formalin-fixed paraffin-embedded tissue.

RESULTS

The foci of myrmecia wart inclusions were characterized by smooth to angular cytoplasmic inclusions in the granular layer, spanning one to three rete. The inclusions stained with an anti-HPV antibody in three specimens.

CONCLUSIONS

This finding of incidental myrmecia wart inclusions in skin biopsies supports latent infection by cutaneotropic, non-carcinogenic HPV.

Nonmelanoma skin cancer in solid organ transplant recipients: update on epidemiology, risk factors, and management

BACKGROUND

Nonmelanoma skin cancers (NMSC) are the most frequently observed cancers in solid organ transplant recipients (SOTR) and may have a significant disease burden.

OBJECTIVE

To provide an update regarding the epidemiology and management of NMSC in SOTR.

RESULTS

Ten-year incidence rates range from 10% in Italy to 20% in Northern Europe to 70% in Australia. More than 50% of NMSC are located on sun-exposed areas (head, dorsum of hands). Many risk factors have been identified, including age at transplantation, fair skin, type of immunosuppressive drugs, cumulative sun exposure, viral infections, and various genetic markers. Patients with a first NMSC have a 49 times higher risk of developing a subsequent NMSC. Skin self-examination and photoprotection should be encouraged in all transplanted patients. Long-term skin surveillance, early diagnosis and aggressive treatment of any suspicious lesion, reduction of immunosuppressive therapy, and conversion to m-TOR inhibitors can be also effective measures for reduction of NMSC incidence.

CONCLUSIONS

NMSC is the most frequent cancer observed in SOTR. Early diagnosis, patient education, and modification of immunosuppression are effective measures for reduction of NMSC incidence.

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.

A case-control study of betapapillomavirus infection and cutaneous squamous cell carcinoma in organ transplant recipients

We examined the association between betapapillomavirus (betaPV) infection and cutaneous squamous cell carcinoma (SCC) in organ transplant recipients. A total of 210 organ transplant recipients with previous SCC and 394 controls without skin cancer were included. The presence of 25 betaPV types in plucked eyebrow hairs was determined using a human papillomavirus (HPV) DNA genotyping assay, and antibodies for the 15 most prevalent betaPV types were detected using multiplex serology. We used multivariate logistic regression models to estimate associations between various measures of betaPV infection and SCC. BetaPV DNA was highly prevalent (>94%) with multiple types frequently detected in both groups. We found a significant association between SCC and the concordant detection of both antibodies and DNA for at least one betaPV type (adjusted OR 1.6; 95% CI 1.1;2.5). A borderline-significant association with SCC was found for HPV36 (adjusted OR 2.4; CI 1.0;5.4), with similar associations for HPV5, HPV9 and HPV24. These data provide further evidence of an association between betaPV infection and SCC in organ transplant recipients. Confirmation of a betaPV profile predictive of risk for SCC may pave the way for clinically relevant pretransplant HPV screening and the development of preventive and therapeutic HPV vaccination.

Transcriptome sequencing demonstrates that human papillomavirus is not active in cutaneous squamous cell carcinoma

Beta-papillomavirus (β-HPV) DNA is present in some cutaneous squamous cell carcinomas (cuSCC), but no mechanism of carcinogenesis has been determined. We used ultra-high throughput sequencing of the cancer transcriptome to assess whether papillomavirus transcripts are present in these cancers. Sixty-seven cuSCC samples were assayed for β-HPV DNA by PCR, and viral loads were measured with type-specific qPCR. Thirty-one SCCs were selected for whole transcriptome sequencing. Transcriptome libraries were prepared in parallel from the HPV18 positive HeLa cervical cancer cell line and HPV16 positive primary cervical and periungual SCC. Thirty percent (20/67) of the tumors were positive for β-HPV DNA, but there was no difference in β-HPV viral load between tumor and normal tissue (p=0.310). Immunosuppression and age were significantly associated with higher viral load (p=0.016 for immunosuppression; p=0.0004 for age). Transcriptome sequencing failed to identify papillomavirus expression in any of the skin tumors. In contrast, HPV 16 and 18 mRNA transcripts were readily identified in primary cervical and periungual cancers and HeLa cells. These data demonstrate that papillomavirus mRNA expression is not a factor in the maintenance of cuSCC.

Organ transplantation and skin cancer: basic problems and new perspectives

Solid organ transplant and subsequent graft survival have increased worldwide, while immunosuppression has prevented rejection with increasing success. Side effects of cutaneous infection and neoplasm, however, affect the majority of solid organ transplant recipients (OTRs). Squamous cell carcinoma of the skin (SCC) is the most common neoplasm overall following organ transplant with a risk that is 60-100 times greater than for the immunocompetent population. This review focuses on questions of ongoing debate about SCC formation in OTRs such as viral carcinogenesis, systemic photoprotection, photosensitization by drugs, the impact of immunosuppressive drugs and inflammation as a driver of carcinogenesis.

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.

Betapapillomavirus infection profiles in tissue sets from cutaneous squamous cell-carcinoma patients

Human papillomaviruses from the genus beta (betaPV) are a possible cause of cutaneous squamous cell carcinoma (SCC). We compared the betaPV infections in SCC and in sets of cutaneous tissues collected from a series of individual SCC patients to determine concordance and to assess the adequacy of eyebrow hairs as noninvasive markers of betaPV infection. Biopsies of SCC tumors, perilesional tissue, normal skin from the mirror image of nonfacial SCC and plucked eyebrow hairs were collected from 21 patients with incident SCC living in Queensland, Australia. These were tested for the presence of DNA from 25 different betaPV types. Overall prevalence of betaPV was high in every sample type, ranging from 81% to 95%. The median number of types was significantly higher in the SCC tumour (6), perilesional skin (5) and eyebrow hairs (5) than in normal skin (2). Comparing SCC tissue with other sample types within patients showed 63 overlapping infections with eyebrow hairs (71%; 95% CI: 60-80); 56 with perilesional skin samples (63%; 95% CI: 52-73) and 23 with normal skin samples (26%; 95% CI: 17-36). The sensitivity of eyebrow hair testing for detection of betaPV in the tumor was 82% (95% CI: 57-96) with concordance defined as 50% of betaPV types in common and 29% (95% CI: 10-56) for 100% concordance. These findings support the concept that perilesional skin represents an area of field change involving betaPV preceding SCC development and indicate that eyebrow hairs can serve to some degree as an easily collected marker of tumor betaPV status in epidemiological studies.

Detection of human papillomavirus infection in trichilemmomas and verrucae using in situ hybridization

BACKGROUND

It is hypothesized that trichilemmomas are 'burned out' verrucae. By performing in situ hybridization using HPV type-specific probes, we explored this concept.

METHODS

Verrucae vulgaris and plantaris were positive controls, and inverted follicular keratoses (IFKs) were negative controls. Additionally, all lesions were tested for HPV genital types (low and high risk).

RESULTS

We analyzed 9 trichilemmomas, 20 verrucae vulgaris, 8 verrucae plana, 3 verrucae plantaris and 6 IFKs. All trichilemmomas were negative for HPV types 1, 2 and genital types. Conversely, 9/20 verrucae vulgaris, 2 verrucae plantaris, and 1 verruca plana were positive for HPV type 2. Among HPV-2 positive lesions, 2/2 verrucae plantaris and 1 verruca vulgaris (chin) were strongly positive for genital-type HPV. One verruca plana (shin) was positive for genital-type HPV only. All 6 IFKs were HPV negative.

CONCLUSIONS

Using HPV type 1 and 2-specific probes and mixed genital-type probes, we were unable to detect HPV in trichilemmomas. This suggests that HPV-1, HPV-2 and low and high risk genital-type HPVs are not involved in the histogenesis of trichilemmoma. We also showed that genital HPV types could be present in non-genital verrucae.

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.

Prevalence and associated factors of betapapillomavirus infections in individuals without cutaneous squamous cell carcinoma

Betapapillomavirus (betaPV) infections are often associated with squamous-cell carcinoma (SCC) and the prevalence of betaPV infections in (immunosuppressed) SCC patients is known to be high. The distribution and possible associated factors of betaPV infections in the general population, however, are largely unknown. To address this issue, betaPV infection was studied in 1405 SCC-free immunocompetent (n=845) and immunosuppressed (n=560) individuals from six countries of different latitudes. A standard study protocol was used to obtain information about age, sex, UV-irradiation and skin type, and from all participants eyebrow hairs were collected for detection and genotyping of 25 established betaPV types using the PM-PCR reverse hybridization assay (RHA) method. The frequency of betaPV-positive participants ranged from 84 to 91 % in the immunocompetent population with HPV23 as the most prevalent type, and from 81 to 98 % in the immunosuppressed population with HPV23 as the most or the second most prevalent type. The median number of infecting betaPV types ranged from four to six in the immunocompetent and from three to six in the immunosuppressed population. Increasing age in the immunocompetent participants and (duration of) immunosuppression in the immunosuppressed patients were associated with betaPV infection. In both groups, sex, skin phototype, sunburns and sun-exposure were not consistently associated with betaPV infection. This study demonstrates that betaPV infections are also highly prevalent in SCC-free individuals, with similar HPV types prevailing in both immunocompetent and immunosuppressed persons. Age and (duration of) immunosuppression were identified as betaPV infection-associated factors, whereas characteristics related to sun exposure and skin type were not.

Betapapillomaviruses: innocent bystanders or causes of skin cancer

Human papillomaviruses (HPV) are found in almost all squamous epithelia where they can cause hyperproliferative disease of mucosa and skin. Mucosal HPV types, such as HPV6 and HPV16, are known to cause anogenital warts and dysplasia or neoplasia, respectively. These HPV types have been studied extensively, and for some of them recently preventive vaccines have become available. Although HPV that populate the skin were the first identified HPV types, knowledge of the pathogenicity of HPV in the cornified epithelia stayed behind. What the majority of cutaneous HPV types do, for instance those belonging to the beta genus (betaPV), is largely unknown. As the number of reports that describe epidemiological associations between markers of betaPV infection and skin cancer gradually increases, the need for basic knowledge about these viruses grows as well. This review aims to picture what is currently known about betaPV with respect to infection, transmission and transformation, in order to envisage their potential role in cutaneous carcinogenesis.

Four novel human betapapillomaviruses of species 2 preferentially found in actinic keratosis

Recent studies have suggested an association between human papillomaviruses (HPVs), particularly species 2 members of the genus Betapapillomavirus, and squamous cell carcinoma (SCC) of the skin. As most of these viruses are uncharacterized, molecular characterization and epidemiology are needed to advance our understanding of their significance in carcinogenesis. This study determined the complete genomes of four betapapillomaviruses of species 2 from skin lesions designated HPV-107, -110 and -111 and FA75[KI88-03], an isolate of an unpublished HPV type, and analysed their prevalence and viral loads in biopsies from SCC, actinic keratosis (AK), basal cell carcinoma, seborrhoeic keratosis and the healthy skin of 263 immunocompetent patients by HPV type-specific real-time PCR assays. Seventeen patients (6.5 %) harboured at least one of the four HPV types in their lesion, whereas seven patients (2.7 %) harboured one or more of the HPV types in healthy skin. Overall, the four viruses were more common in AK than in healthy skin (odds ratio 5.0, 95 % confidence interval 1.4–17.5), but the prevalence and viral loads were low. This characterization of HPV-107, -110 and -111 and FA75[KI88-03] expands the heterogeneity of members of species 2 of the genus Betapapillomavirus. However, as these types were found in only a few samples and in low amounts, a possible role in carcinogenesis remains elusive.

Specific betapapillomaviruses associated with squamous cell carcinoma of the skin inhibit UVB-induced apoptosis of primary human keratinocytes

Epidemiological studies have shown an association between infections by specific betapapillomaviruses, such as human papillomavirus (HPV) types 5 and 8, and cutaneous squamous cell carcinoma (SCC). The role of betapapillomaviruses in the development of cutaneous SCC is, however, still enigmatic. The ability to inhibit UVB-induced apoptosis, as demonstrated for HPV5 in vitro, may be important in this respect, as survival of DNA-damaged and mutated cells increases the risk of transformation. The aim of this study was to assess whether inhibition of UVB-induced apoptosis is a general property of betapapillomaviruses and to identify apoptotic factors that are potentially involved in this process. Primary human keratinocytes transduced with E6 and E7 of selected betapapillomaviruses (HPV5, HPV8, HPV15, HPV20, HPV24 and HPV38) were characterized and subjected to UVB irradiation. HPV8- and HPV20-expressing keratinocytes in particular showed fewer signs of apoptosis, as demonstrated by lower levels of active caspase 3, less enzymic caspase activity and less DNA fragmentation. The observed inhibition of UVB-induced apoptosis was mediated by E6 and coincided with reduced steady-state expression of the pro-apoptotic protein Bax. In conclusion, E6 of HPV8 and HPV20 reduces the apoptotic responses upon UVB irradiation when expressed in primary human keratinocytes. Infections with HPV8 and HPV20 may therefore augment the carcinogenic effect of UV radiation and potentially contribute to oncogenic transformation of the skin.

Seroprevalence of 34 human papillomavirus types in the German general population

The natural history of infections with many human papillomavirus (HPV) types is poorly understood. Here, we describe for the first time the age- and sex-dependent antibody prevalence for 29 cutaneous and five mucosal HPV types from 15 species within five phylogenetic genera (alpha, beta, gamma, mu, nu) in a general population. Sera from 1,797 German adults and children (758 males and 1,039 females) between 1 and 82 years (median 37 years) were analysed for antibodies to the major capsid protein L1 by Luminex-based multiplex serology. The first substantial HPV antibody reactions observed already in children and young adults are those to cutaneous types of the genera nu (HPV 41) and mu (HPV 1, 63). The antibody prevalence to mucosal high-risk types, most prominently HPV 16, was elevated after puberty in women but not in men and peaked between 25 and 34 years. Antibodies to beta and gamma papillomaviruses (PV) were rare in children and increased homogeneously with age, with prevalence peaks at 40 and 60 years in women and 50 and 70 years in men. Antibodies to cutaneous alpha PV showed a heterogeneous age distribution. In summary, these data suggest three major seroprevalence patterns for HPV of phylogenetically distinct genera: antibodies to mu and nu skin PV appear early in life, those to mucosal alpha PV in women after puberty, and antibodies to beta as well as to gamma skin PV accumulate later in life.

Extension of the typing in a general-primer-PCR reverse-line-blotting system to detect all 25 cutaneous beta human papillomaviruses

beta-Papillomaviruses (PV) seem to be involved in the pathogenesis of cutaneous squamous cell carcinoma and its early stage actinic keratosis. In this study, typing was extended of a previously described consensus primer-mediated beta- and gamma-cutaneous HPV PCR method followed by reverse-line-blotting (BGC-PCR/RLB) to detect all 25 known beta-PV and to examine their prevalence in actinic keratosis. The typing format of the BGC-PCR assay was extended by adding hybridization probes of six beta-PV (HPV 75, 76, 80, 92, 93, and 96) to the RLB system. Subsequently, tumor and normal skin tissues were collected from 75 patients with actinic keratosis, allowing typing for a total of 25 beta- and 5 gamma-types. The analytical sensitivity was between 10 copies (HPV 75, 80, 92, 93, and 96) and 100 copies (HPV 76). Except for that of HPV 76, none of the added probes showed any cross-hybridization with other beta-HPV. HPV DNA was detected in 45% of actinic keratosis and in 33% of normal skin by BGC-PCR, and at least one of the six added beta-types was present in 19% of actinic keratoses and in 13% of normal skin. Six beta-HPV types were added successfully to the typing format of the BGC-PCR/RLB system. The potential role of these types in the development of non-melanoma skin cancer awaits further studies.

Betapapillomaviruses frequently persist in the skin of healthy individuals

Infections with human papillomaviruses (HPVs) belonging to the genus Betapapillomavirus have been linked to the development of non-melanoma skin cancer. Although persistence is expected, systematic investigation of this aspect of betapapillomavirus (beta-PV) infection has not been conducted. This study investigated the prevalence and persistence of 25 known beta-PV types in the skin of immunocompetent individuals. Over a 2 year period, eight consecutive plucked eyebrow hair samples taken from 23 healthy individuals were analysed for the presence of beta-PV DNA. Using a recently published general beta-PV PCR and genotyping method, 61% of the individuals were beta-PV DNA positive for one or more types at intake, whereas during follow-up this percentage rose to 96%. HPV23 was the most frequently detected beta-PV type. Type-specific beta-PV DNA was detected over 6 months or longer in 74% of the individuals. In 57% of the individuals, DNA from multiple beta-PV types was detected simultaneously for 6 months or longer. When the detection intervals of all beta-PV type-specific infections in the study population were considered, a substantial proportion, 48%, lasted at least half a year. The consistent beta-PV patterns found over time in most individuals strongly suggested that beta-PV DNA detection in plucked eyebrow hairs reveals true beta-PV infection. If the minimum interval of detection was set at 6 months, persistent beta-PV infections were found in the majority of the study population (74%).

New evidence for geographic variation in the role of human papillomavirus in tonsillar carcinogenesis

AIMS

Our previous studies of tonsillar cancers from New South Wales, Australia, and Jilin Province in the north-east of China, provided evidence that the proportion of these cancers attributable to human papillomavirus (HPV) varies geographically. This study provides the first data on HPV in tonsillar cancers from Hong Kong.

METHODS

A total of 49 Hong Kong tonsillar cancers were analysed for HPV DNA by PCR/sequencing and for p16(INK4A), retinoblastoma (pRb) protein, cyclin D1 and p53 expression by semiquantitative immunohistochemistry as evidence of virus causality. Results were compared with those from New South Wales and Jilin Province.

RESULTS

Of the 31 Hong Kong cancers with amplifiable DNA, nine (29%) were HPV positive by PCR compared with 46% from New South Wales and 0% from Jilin Province. HPV positivity correlated with female gender, young age, over-expression of p16(INK4A) and loss of pRb and cyclin D1. Five-year disease-specific survival for patients with HPV positive and HPV negative cancers was 82 and 42%, respectively. Relationships between HPV status and cell protein expression in Hong Kong cancers were consistent with those from New South Wales and Jilin Province. The proportion of HPV-associated cancers reflected the relative incidence of oropharyngeal cancer in these regions.

CONCLUSIONS

HPV is responsible for a small proportion of tonsillar cancers in Hong Kong patients. Differences in the proportions of tumours attributable to HPV in Hong Kong, New South Wales and Jilin Province may be due to environmental, cultural or genetic factors in the different populations.

Beta-papillomaviruses in anogenital hairs plucked from healthy individuals

A total of 150 specimens of anogenital hairs plucked from the scrotal, pubic, and perianal region of 51 immunocompetent healthy male individuals were tested for the presence of beta-papillomaviruses (beta-HPV) using the nested M(a)/H(a) polymerase chain reaction. Beta-HPV were found in a total of 38 (25.3%) of 150 hair samples. According to the sampling sites, beta-HPV were detected in 18/51 (35.3%), 13/50 (26.0%), and 7/49 (14.3%) plucked hair samples obtained from the pubic, scrotal, and perianal region, respectively. The prevalence of beta-HPV in the plucked pubic hairs was significantly higher than in the perianal hairs (P = 0.013). In contrast, the difference in the prevalence of beta-HPV in the pubic and scrotal hairs as well as in scrotal and perianal hairs did not reach statistical significance (P = 0.302 and P = 0.227, respectively). The difference in the lifetime-cumulative sun exposure is the most likely explanation for the differences obtained on beta-HPV prevalence. Beta-HPV genotype HPV-38 was detected most frequently, followed by HPV-36, HPV-15, and HPV-14D. In addition to the beta-HPV recognized officially five partial DNA sequences suggesting putative new HPV genotypes were identified.

Changes of epidermodysplasia verruciformis in benign skin lesions: the EV acanthoma

Foci of histological changes of epidermodysplasia verruciformis (EV) were noted in five benign skin lesions. These skin lesions included an intradermal nevus, a pigmented seborrheic keratosis, an isolated papule on the forearm, a perianal lesion, and an acantholytic acanthoma. Because the changes resembled true EV so strongly despite the absence of clinical EV in these patients, we searched for EV-human papilloma virus (HPV) types in these skin lesions. Polymerase chain reaction (PCR) analysis on the formalin-fixed, paraffin-embedded blocks was performed. As a positive control, we included tissue from two HIV-positive patients with clinical EV proven by biopsy. Studies were also performed on five other archived biopsies that did not show changes of EV on multiple tissue sections. A nested PCR method detected EV-HPV types in three of the five benign skin lesions showing EV changes as well as in the positive controls. EV changes and EV-HPV can be found incidentally on biopsy in the absence of clinical EV; when such changes are the major histopathological finding in an isolated skin lesion, the lesion should be termed an EV acanthoma.

Evaluation of a novel highly sensitive, broad-spectrum PCR-reverse hybridization assay for detection and identification of beta-papillomavirus DNA

Human papillomavirus can be detected by amplification of viral DNA. A novel one-step PCR (PM-PCR) was evaluated for amplification of a 117-bp fragment from the E1 region. It permitted ultrasensitive detection of all 25 known human papillomavirus genotypes from the beta-papillomavirus genus. The intra- and intertypic sequence variations of the 77-bp interprimer region were studied. Genotype-specific probes as well as general probes were selected for the 25 established beta-papillomavirus types, and a reverse hybridization assay (RHA) was developed (PM-PCR RHA method). The analytical sensitivity of the PM-PCR RHA method was 10 to 100 viral genomes. The one-step PM-PCR turned out to be more sensitive than the previously described nested MaHa-PCR for beta-papillomavirus detection. The PM-PCR RHA method was able to detect and identify beta-papillomavirus types in frozen patient material as well as in poorly amplifiable material such as formalin-fixed, paraffin-embedded skin biopsy specimens. Inter- and intralaboratory variability experiments showed that the reproducibility of the assay was very high. In conclusion, the one-step PM-PCR together with the RHA allows extremely sensitive, specific, and reproducible detection of beta-papillomavirus DNA as well as reliable identification of beta-papillomavirus genotypes in both fresh and paraffin-embedded patient material.

Markers of cutaneous human papillomavirus infection in individuals with tumor-free skin, actinic keratoses, and squamous cell carcinoma

Separately, actinic keratosis (AK) and cutaneous squamous cell carcinoma (SCC) have been associated with cutaneous human papillomavirus (HPV) infections. To further explore the association between HPV infection and SCC development, we determined markers of cutaneous HPV infection within a single population in persons with precursor lesions (AK), cancerous lesions (SCC), and without. Serum and plucked eyebrow hairs were collected from 57 tumor-free controls, 126 AK, and 64 SCC cases. Presence of HPV L1 and E6 seroreactivity and viral DNA were determined for HPV types 5, 8, 15, 16, 20, 24, and 38. Significant positive associations with increasing severity of the lesions (controls, AK, and SCC, respectively) were observed for overall HPV L1 seropositivity (13%, 26%, and 37%) and for HPV8 (4%, 17%, and 30%). In parallel, the proportion of L1 seropositive individuals against multiple HPV types increased from 14% to 39% and 45%. The overall E6 seroreactivity, however, tended to decline with AK and SCC, especially for HPV8 (21%, 11%, and 2%). HPV DNA positivity was most prevalent in the AK cases (54%) compared with the SCC cases (44%) and the tumor-free controls (40%). Among all participants, there was a positive trend between overall HPV DNA positivity and L1 seropositivity, but not E6 seropositivity. Taken together, our data suggest that cutaneous HPV infections accompanied by detectable HPV DNA in eyebrow hairs and HPV L1 seropositivity, but not E6 seropositivity, are associated with an increased risk of AK and SCC.

Diversity of cutaneous human papillomavirus types in individuals with and without skin lesion

BACKGROUND

Human papillomavirus (HPV) is ubiquitous on the skin of normal and immunosuppressed hosts.

OBJECTIVE

We describe the diversity of HPV types in skin specimens using PCR-sequencing directly and after cloning with FAP59/64 or HVP2/B5 primers.

STUDY DESIGN

Cross-sectional analysis of skin swabs.

RESULTS

Seventy-five (92.6%) of 81 subjects provided samples that could be analysed with PCR (34 healthy controls <50 years old, 13 healthy controls > or =50 years old, 12 with actinic keratosis (AK), 8 with squamous cell carcinoma (SCC) and 8 renal transplant recipients). HPV DNA was detected more frequently with FAP59/64 (68/75, 91%) than with HVP2/B5 (9/75, 12%) (p<0.001). Agreement of typing results using FAP59/64 primers with both sequencing strategies was fair (mean kappa 0.56+/-0.19, 95% CI: 0.46-0.65). HPV species 1 and 2 of the beta-papillomavirus genus were associated with the presence of AK (OR=24.8, 95% CI: 2.3-262.6). A greater number of HPV types per sample was found in individuals with AK or SCC (p=0.046) or AK alone (p=0.02), than in healthy participants.

CONCLUSION

HPV infection on the skin is best evaluated with a combination of primers and sequencing strategies. Novel putative types were frequently detected in SCC. Skin lesions have a greater number of HPV types than normal skin.

Epidermodysplasia Verruciformis: An Unusual Presentation

BACKGROUND Epidermodysplasia verruciformis (EV) is a rare autosomal recessive genetic disorder of the immune system manifested by increased susceptibility to cutaneous human papillomavirus (HPV) infection beginning from the early years of life, and compromising lesions resembling flat warts, especially on the distal extremities and the face; but malignant transformation occurs in sun-exposed areas within the third or fourth decade of life. OBJECTIVE We describe two case reports of epidermodysplasia verruciformis, one of which was onset and had more aggressive features than the usual presentation. METHODS Intermittent surgical excision of the tumoral lesions were performed in the first case, whereas only one surgical intervestion was sufficient in the second case. RESULTS The early onset case was more aggressive, and new tumoral lesions were seen, whereas the other patients was free of the disease for 2 years.CONCLUSION Epidermodysplasia verruciformis possess multi factorial etiologies, and the main prognostic factor of the behavior of the disease may be the family history and genetic susceptibility.

Human papillomavirus gene expression in cutaneous squamous cell carcinomas from immunosuppressed and immunocompetent individuals

Epidermodysplasia verruciformis (EV)-type human papillomavirus (HPV) DNA have been detected by PCR in squamous cell carcinomas (SCC) from both organ transplant recipients (OTR) and immunocompetent individuals. Their role in skin cancer remains unclear, and previous studies have not addressed whether the viruses are transcriptionally active. We have used in situ hybridization to investigate the transcriptional activity and DNA localization of HPV. EV-HPV gene transcripts were demonstrated in four of 11 (36%) OTR SCC, one of two (50%) IC SCC, and one of five (20%) OTR warts positive by PCR. Viral DNA co-localized with E2/E4 early region gene transcripts in the middle or upper epidermal layers. Non-EV cutaneous HPV gene transcripts were demonstrated in one of five (20%) OTR SCC and four of 10 (40%) OTR warts. In mixed infections transcripts for both types were detected in two of six (33%) cases. Our results provide evidence of EV-HPV gene expression in SCC; although only a proportion of tumors were positive, the similarly low transcriptional activity in warts suggests this is an underestimate. These observations, together with emerging epidemiological and functional data, provide further reason to focus on the contribution of EV-HPV types to the pathogenesis of cutaneous SCC.

The papillomavirus life cycle

Papillomaviruses infect epithelial cells, and depend on epithelial differentiation for completion of their life cycle. The expression of viral gene products is closely regulated as the infected basal cell migrates towards the epithelial surface. Expression of E6 and E7 in the lower epithelial layers drives cells into S-phase, which creates an environment that is conducive for viral genome replication and cell proliferation. Genome amplification, which is necessary for the production of infectious virions, is prevented until the levels of viral replication proteins rise, and depends on the co-expression of several viral proteins. Virus capsid proteins are expressed in cells that also express E4 as the infected cell enters the upper epithelial layers. The timing of these events varies depending on the infecting papillomavirus, and in the case of the high-risk human papillomaviruses (HPVs), on the severity of neoplasia. Viruses that are evolutionarily related, such as HPV1 and canine oral papillomavirus (COPV), generally organize their productive cycle in a similar way, despite infecting different hosts and epithelial sites. In some instances, such as following HPV16 infection of the cervix or cottontail rabbit papillomavirus (CRPV) infection of domestic rabbits, papillomaviruses can undergo abortive infections in which the productive cycle of the virus is not completed. As with other DNA tumour viruses, such abortive infections can predispose to cancer.

Detection of various types of human papillomavirus DNA, mainly belonging to the cutaneous-group, more frequently in normal tissue than in squamous cell carcinomas of the lip

BACKGROUND

Mucosal high-risk human papillomaviruses (HPVs), such as type 16, are detectable in oral cancers, especially of the oropharynx and tonsils, and there is evidence that they play a pathogenetic role in some cases. However, information is limited about their significance for cancers of the vermilion of the lip.

OBJECTIVE

To determine the detection rate, types and localization of HPVs in squamous cell carcinomas (SCCs) of the lip.

METHODS

Nested PCR for cutaneous HPVs, including epidermodysplasia verruciformis-related HPV (EV-HPV), and single PCR for mucosal HPVs, were conducted for a total of 27 SCCs and normal samples from 30 individuals. Tyramide-based in situ hybridization (ISH) was also applied.

RESULTS

Various types of HPVs were detected, particularly from normal individuals. Among the kinds of the HPV types detected in this study, half were found by PCR using a primer pair, which we newly designed. The prevalence of HPV was 5 out of 27 SCCs (ca. 18%) and 10 out of 30 normal individuals (ca. 33%). They were the entire cutaneous-group except for two, from one SCC and one normal individual.

CONCLUSION

On the surface of the normal lip various types of mainly cutaneous-group HPVs may be present, but there does not appear to be any obvious association with SCCs developing in this site.

Detection of human papillomavirus type 56 DNA, belonging to a mucous high-risk group, in hair follicles in the genital area of a woman no longer suffering from viral warts

BACKGROUND

Human papillomaviruses (HPVs) parasitize human epithelium, but it is not clear where they reside when they do not cause apparent infection. Hair follicles are important candidates as reservoirs.

OBJECTIVES

A patient reported previously by us as having perianal warts caused mainly by HPV 56, demonstrated hair follicles in her genital area which bulged a little from the surface and appeared somewhat enlarged. We therefore examined whether DNA of HPV 56, a member of the mucous high-risk group, might be detectable in these structures.

METHODS

We obtained plucked hairs and performed an examination by polymerase chain reaction and subsequent reverse-phase dot blot hybridization (PCR-RDBH) and in situ hybridization (ISH).

RESULTS

Strong positive signals were obtained not only with PCR-RDBH but also with ISH.

CONCLUSIONS

Hair follicles in the genital area might serve as reservoirs for HPVs belonging to the mucous high-risk group.

Pigmented Epidermal Plaques in Three Dogs

Papillomavirus was identified in pigmented epidermal plaques (PEP) from three dogs: a miniature schnauzer with hyperadrenocorticism and hypoglobulinemia, an American Staffordshire terrier with hypoglobulinemia, and a Pomeranian with unconfirmed hypothyroidism. Squamous cell carcinoma (SCC) arose within several plaques in the Pomeranian. Clinical improvement coincided in the first two cases with treatment of the concurrent disease and the administration of low-dose oral interferon-α. This is the first report of PEP in an American Staffordshire terrier and a Pomeranian. The potential for malignant transformation of PEP to SCC emphasizes the need for recognition and clinical management of PEP.