Human papillomaviruses in non-melanoma skin cancer

Human papillomavirus type 7 identified in digitated warts on facial seborrhoeic eczema of a non-butcher immunocompetent individual

Human papillomavirus type 7 (HPV7) is frequently found in butchers' warts and has been demonstrated in several warts of immunocompromised hosts. HPV7 is rarely identified in non-butchers' warts, especially in individuals with normal immune status. We describe the first case of multiple HPV7-induced digitated warts which were developed on the face of a 68-year-old Japanese man, whose immune status was normal and who had no history of meat handling. Interestingly, the warts were developed exclusively on the skin affected with seborrhoeic eczema in the face, suggesting that some biologically active factors associated with seborrhoeic eczema and anatomical factors of sun-exposed facial skin might contribute to the development of HPV7-induced warts.

Aberrant expression and high-frequency mutations of SHARPIN in nonmelanoma skin cancer

Squamous cell carcinoma (SCC) and basal cell carcinoma (BCC) have exhibited a marked increase in incidence in previous decades and are the most common malignancies in Caucasian populations. Src homology 3 and multiple ankyrin repeat domains protein-associated RH domain-interacting protein (SHARPIN) has been identified as a commonly overexpressed proto-oncogene in several types of visceral cancer. However, to the best of our knowledge, the functions of SHARPIN in nonmelanoma skin cancer (NMSC) have not been described. The present study aimed to investigate the expression of SHARPIN protein and SHARPIN mutations in NMSC. A total of 85 BCC, 77 SCC and 21 keratoacanthoma (KA) formalin-fixed paraffin-embedded (FFPE) samples were collected. SHARPIN expression was detected using immunohistochemistry. DNA was extracted from the FFPE samples, and the sequences of SHARPIN were analyzed using polymerase chain reaction. In addition, high and moderate expression levels of SHARPIN were observed in normal skin tissues and KA samples. However, the expression of SHARPIN was absent in cancer nests and was significantly low in precancerous NMSC lesions. The total mutation frequency of SHARPIN was 21.8% in BCC and 17.0% in SCC. These data indicate that SHARPIN may serve a tumor-suppressing role and be a promising diagnostic, prognostic and therapeutic biomarker in NMSC.

HPV-47-Induced and Tattoo-associated Verrucae Planae: Report of a Case and Review of the Literature

The human papillomavirus (HPV), of which more than 200 different types have so far been identified, is an infectious disease impacting skin and mucous membranes. Several genera exist with distinct clinical impact. However, with ornamental tattoos increasing in popularity, a number of mostly cutaneous side effects have also been reported, such as infections, allergic reactions, or even a rise of malignant tumours within the tattoo. We report the first case of a β1-HPV-type infection in cutaneous lesions in terms of verrucae vulgares near a tattoo in an immunocompetent adult without pre-existing conditions, and discuss possible relationships and etiologic concerns of this association.

Immunologic Control of Mus musculus Papillomavirus Type 1

Persistent papillomas developed in ~10% of out-bred immune-competent SKH-1 mice following MusPV1 challenge of their tail, and in a similar fraction the papillomas were transient, suggesting potential as a model. However, papillomas only occurred in BALB/c or C57BL/6 mice depleted of T cells with anti-CD3 antibody, and they completely regressed within 8 weeks after depletion was stopped. Neither CD4+ nor CD8+ T cell depletion alone in BALB/c or C57BL/6 mice was sufficient to permit visible papilloma formation. However, low levels of MusPV1 were sporadically detected by either genomic DNA-specific PCR analysis of local skin swabs or in situ hybridization of the challenge site with an E6/E7 probe. After switching to CD3+ T cell depletion, papillomas appeared upon 14/15 of mice that had been CD4+ T cell depleted throughout the challenge phase, 1/15 of CD8+ T cell depleted mice, and none in mice without any prior T cell depletion. Both control animals and those depleted with CD8-specific antibody generated MusPV1 L1 capsid-specific antibodies, but not those depleted with CD4-specific antibody prior to T cell depletion with CD3 antibody. Thus, normal BALB/c or C57BL/6 mice eliminate the challenge dose, whereas infection is suppressed but not completely cleared if their CD4 or CD8 T cells are depleted, and recrudescence of MusPV1 is much greater in the former following treatment with CD3 antibody, possibly reflecting their failure to generate capsid antibody. Systemic vaccination of C57BL/6 mice with DNA vectors expressing MusPV1 E6 or E7 fused to calreticulin elicits potent CD8 T cell responses and these immunodominant CD8 T cell epitopes were mapped. Adoptive transfer of a MusPV1 E6-specific CD8+ T cell line controlled established MusPV1 infection and papilloma in RAG1-knockout mice. These findings suggest the potential of immunotherapy for HPV-related disease and the importance of host immunogenetics in the outcome of infection.

While most patients clear human papillomavirus (HPV) infection, some develop persistent papillomas, especially if immunocompromised. Likewise, we find a fraction of outbred SKH-1 mice challenged with Mus musculus papillomavirus type 1 (MusPV1/MmuPV1) develop persistent papillomas, whereas most SKH-1 mice, as seen for the inbred C57BL/6 and BALB/c strains, clear the infection. Viral clearance requires both CD4+ and CD8+ T cells, and depletion of either subset permits persistent but subclinical infection. In C57BL/6 mice, CD8+ T cell epitopes were mapped to MusPV1 E6 and E7; however the CD8+ T cell response to E6 dominated and correlated with spontaneous regression. A MusPV1 E6-specific CD8+ T cell line was developed by vaccination and culture in vitro, and its systemic administration once was sufficient to effect papilloma clearance in an immunodeficient mouse. Our observations in inbred and outbred mice challenged with MusPV1 suggest promise for immunotherapy to treat HPV-associated disease.

Cross-roads in the classification of papillomaviruses

Acceptance of an official classification for the family Papillomaviridae based purely on DNA sequence relatedness, was achieved as late as 2003. The rate of isolation and characterization of new papillomavirus types has greatly depended on and subjected to the development of new laboratory techniques. Introduction of every new technique led to a temporarily burst in the number of new isolates. In the following, the bumpy road towards achieving a classification system combined with the controversies of implementing and accepting new techniques will be summarized. An update of the classification of the 170 human papillomavirus (HPV) types presently known is presented. Arguments towards the implementation of metagenomic sequencing for this rapidly growing family will be presented.

Differential regulation of cutaneous oncoprotein HPVE6 by wtp53, mutant p53R248W and ΔNp63α is HPV type dependent

UV exposure and p53 mutations are major factors in non-melanoma skin cancer, whereas a role for HPV infections has not been defined. Previous data demonstrated the wtp53-mediated degradation of cutaneous HPV20E6 by caspase-3. ΔNp63α and hot-spot mutant p53R248W conveyed a protective effect on HPV20E6 under these conditions. We demonstrate a differential regulation by wtp53 of the E6 genes of cutaneous types HPV4, HPV5, HPV7, HPV27, HPV38, HPV48, HPV60 and HPV77. Caspase- or proteasome-mediated down-regulation was HPV type dependent. Mutant p53R248W up-regulated expression of all these E6 proteins as did ΔNp63α except for HPV38E6 which was down-regulated by the latter. None of these cellular proteins affected HPV41E6 expression. Ectopic expression of both mutp53R248W and ΔNp63α in the normal NIKS keratinocyte cell line harbouring endogenous p53 and p63however led to a down-regulation of HPV20E6. We demonstrate that HPV20E6 expression in these cells is modulated by additional, yet unidentified, cellular protein(s), which are not necessarily involved in apoptosis or autophagy. We further demonstrate proliferation of HPV20E6-expressing keratinocytes. Levels of proteins involved in cell cycle control, cyclin-D1, cdk6 and p16^INK4a, phosphorylated pRB, as well as c-Jun and p-c-Jun, were all increased in these cells. HPV20E6 did not compete for the interaction between p16^INK4a with cyclin-D1 or cdk6. Phosphorylation of pRB in the HPV20E6 expressing cells seems to be sufficient to override the cytokenetic block induced by the p16^INK4a/pRB pathway. The present study demonstrates the diverse influence of p53 family members on individual cutaneous HPVE6 proteins. HPV20E6 expression also resulted in varying protein levels of factors involved in proliferation and differentiation.

Association of human papilloma virus with pterygia and ocular-surface squamous neoplasia

There are more microorganisms that colonize the human body than resident cells; some are commensal whereas others are pathogenic. Pathogenic microorganisms are sensed by the innate or adaptive immune system, an immune response is initiated, and the infection is often cleared. Some microorganisms have developed strategies to evade immune defenses, ensuring their long-term survival with potentially devastating consequences for the host. Approximately 18% of all cancers can be attributed to infective agents; the most common being Helicobacter pylori, Human papilloma virus (HPV) and Hepatitis B and C virus in causing stomach, cervical and liver carcinoma, respectively. This review focuses on whether HPV infection is necessary for initiating pterygia, a common benign condition and ocular-surface squamous neoplasia (OSSN), a rare disease with metastatic potential. The search engine PubMed was used to identify articles from the literature related to HPV and pterygium or conjunctival neoplasia. From 34 investigations that studied HPV in pterygia and OSSN, a prevalence rate of 18.6% (136/731) and 33.8% (144/426), respectively, was recorded. The variation in HPV prevalence (0-100%) for both disease groups may have arisen from study-design faults and the techniques used to identify the virus. Overall, the data suggest that HPV is not necessary for initiating either condition but may be a co-factor in susceptible hosts. Currently, over 60 million people worldwide have been immunized with HPV vaccines, but any effect on pterygium and OSSN development may not be known for some time as these lesions can evolve over decades or occur in older individuals.

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

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

Papillomavirus-Associated Cutaneous Neoplasia in Mammals

For humans, strong evidence indicates that some mucosal papillomavirus (PV) types cause genital and oral neoplasia, and weaker evidence suggests that some cutaneous PVs may cause cutaneous squamous cell carcinomas (SCC). For nonhuman species, strong evidence supports a causal role of PVs in the development of feline and equine sarcoids. Likewise, PVs are believed to cause cutaneous SCCs in rabbits, western barred bandicoots, and some rodents. Furthermore, some evidence suggests that PVs may influence the development of both feline and canine cutaneous SCCs. This review discusses the evidence that PVs cause human cutaneous SCCs and the proposed mechanisms for this action. It then reviews preneoplastic and neoplastic skin diseases that are associated with PV infection in nonhuman mammals.

Human papillomavirus infection and ultraviolet light exposure as epidermoid inclusion cyst risk factors in a patient with epidermodysplasia verruciformis?

Epidermoid inclusion cysts are common lesions with unclear etiology. We sought to examine evidence for human papillomavirus (HPV) infection and ultraviolet light (UV) exposure as risk factors in the formation of epidermoid inclusion cysts. We performed HPV typing of biopsied cysts with polymerase chain reaction for a patient with darkly-pigmented skin, epidermodysplasia verruciformis (EV) and more than 250 photodistributed cysts. HPV types 8 and 6 DNA was demonstrated within biopsy specimens of 3 cysts. In one biopsy specimen, abnormal keratinocytes bridging the follicular infundibulum were seen. We concluded that UV exposure and HPV viral infection may be risk factors for the formation of epidermoid inclusion cysts.

Familial clustering of cancer at human papillomavirus-associated sites according to the Swedish Family-Cancer Database

Familial aggregation of cervical cancer has been demonstrated previously, however aggregation of other human papillomavirus-associated anogenital, upper aerodigestive tract and skin cancers has not been fully characterized. The Swedish Family-Cancer Database, which contains reliable data on cancer incidence and nuclear family linkages for all residents of Sweden between 1958 and 2004, was used to calculate standardized incidence ratios (SIR) and 95% confidence intervals for offspring site-specific cancer risks according to site-specific cancer in sibling and parental probands. Offspring cancer risk was significantly increased when either a sibling or parent was affected at the same site for penile squamous cell carcinoma (SCC, SIR = 7.54), cervical adenocarcinoma (AC, SIR = 2.31), vulvar SCC (SIR = 2.27), skin SCC (SIR = 2.14), rectal AC (SIR = 1.86), in situ cervical SCC (SIR = 1.80), invasive cervical SCC (SIR = 1.77) and upper aerodigestive tract SCC (SIR = 1.57). Significant aggregation on the order of 2-fold between anogenital cancers at different sites or histologies was also observed. In situ cervical SCC risk in offspring was strongly influenced by siblings affected with oropharyngeal SCC (SIR = 3.17) and tonsillar SCC (SIR = 1.84). Familial skin SCC was largely unassociated with anogenital or upper aerodigestive tract cancer risk in offspring. These data suggest that common host factors exist among individuals affected with anogenital and upper aerodigestive tract cancers.

E6/E7 expression of human papillomavirus type 20 (HPV-20) and HPV-27 influences proliferation and differentiation of the skin in UV-irradiated SKH-hr1 transgenic mice

The functional role of UV irradiation, in combination with the E6 and E7 proteins of the cutaneous human papillomavirus (HPV) types in the malignant conversion of benign papillomatous lesions, has not been elucidated. Transgenic SKH-hr1 hairless mice expressing HPV-20 and HPV-27 E6 and E7 proteins in the suprabasal compartment were generated and exposed to chronic UV irradiation. Histological and immunohistochemical examination of skin samples revealed enhanced proliferation of the epidermal layers and papilloma formation in both transgenic strains in comparison to what was observed with nontransgenic mice. Squamous cell carcinoma developed in the HPV-20 E6/E7 transgenic line as well as in the HPV-27 E6/E7 transgenic line. Several weeks after cessation of UV-B exposure, enhanced proliferation, as measured by BrdU incorporation, was maintained only in HPV-20 transgenic skin. Keratin 6 expression was increased in the transgenic mice throughout all cell layers. Expression of the differentiation markers involucrin and loricrin was reduced and disturbed. p63alpha expression was differentially regulated with high levels of cytoplasmic expression in clusters of cells in the granular layer of the skin in the transgenic lines 20 weeks after cessation of UV-B exposure, in contrast to uninterrupted staining in the nontransgenic lines. p53 was expressed in clusters of cells in nontransgenic and HPV-27 transgenic mice, in contrast to an even distribution in a higher number of cells in HPV-20 transgenic animals.

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.

TAp63alpha indirectly regulates a cutaneous HPV promoter through complex formation with Jun family members

The p63alpha isoforms of the p53 family have been demonstrated to play a crucial role in the development and differentiation of the skin. We show that expression of the TAp63alpha isoform leads to an upregulation of the cutaneous papillomavirus HPV 20 promoter, which is increased at least three-fold when c-Jun is co-expressed, in contrast to a minimal increase in activity in the presence of c-Jun alone. Co-expression of TAp63alpha with JunB or JunD, respectively, and in combination, leads to a reduction in the viral promoter activation measured by the expression of TAp63alpha alone. JunB and JunD also inhibits the additive effect exerted on the TAp63alpha activation by c-Jun. Co-immunoprecipitation assays demonstrate a complex formation of c-Jun, JunB and JunD with TAp63alpha through the SAM domain mediating protein-protein interactions, which is characteristic for p63alpha. Co-expression of p53 mutant R248W not only downregulates the differential modulation of the viral promoter by TAp63alpha alone and in the presence of the Jun family members, but leads to a reduction in the protein levels of the overexpressed c-Jun, JunB, JunD, as well as TAp63alpha. This model system provides insight into yet unknown pathways through which TAp63alpha and Jun may cooperate in the pathogenesis of HPV associated cutaneous lesions.

Detection of epidermodysplasia verruciformis-associated human papillomavirus DNA in nongenital seborrhoeic keratosis

BACKGROUND

DNA of epidermodysplasia verruciformis (EV)-associated human papillomaviruses (HPVs) has been widely detected in lesions of malignant skin tumours, benign tumours and other proliferative diseases of epithelial origin.

OBJECTIVES

To investigate the presence of EV-associated HPV DNA in nongenital seborrhoeic keratosis (SK) and to elucidate the prevalence of distinct HPV genotypes.

METHODS

We investigated HPV DNA in 55 nongenital SK biopsies, which were compared with 48 normal skin biopsies (healthy controls) using a nested polymerase chain reaction (PCR) using consensus primers CP65/CP70 and CP66/CP69. The positive PCR products were retracted and used to prepare recombination clones with T-vector. Distinct clones were analysed with endonucleases, and HPV genotypes were identified by direct sequencing.

RESULTS

EV-associated HPV DNA was detected in 42 of 55 (76%) nongenital SK biopsies vs. only 13 of 48 (27%) healthy controls (chi2 = 22.087; P < 0.005). The prevalence was higher in patients with more than five lesions than in those with only one lesion (P < 0.05). Ten distinct HPV genotypes were detected in the nongenital SK biopsies: HPV 20, 23, 5, renal transplant recipient (RTR) X7, HPV 17, 37, 17b, RTRX4, RTRX4b and strain SK3. HPV 20 was found in 26 of 42 (62%) positive specimens, followed by HPV 23 (11 of 42, 26%) and HPV 5 (six of 42, 14%). Existence of multiple HPV genotypes was observed in 12 of 42 (29%) positive specimens. In healthy controls, five genotypes of EV-associated HPV (HPV 20, 23, 5, 17 and RTRX4) were detected, with the same predominant genotype of HPV 20 (five of 13, 38%). Several distinct HPV genotypes were found to coexist in four of 13 (31%) positive specimens.

CONCLUSIONS

This study provides some evidence that EV-associated HPVs might play a part in the pathogenesis of nongenital SK.

Presence of papillomavirus sequences in condylomatous lesions of the mamillae and in invasive carcinoma of the breast

BACKGROUND

Viruses including Epstein-Barr virus (EBV), a human equivalent of murine mammary tumour virus (MMTV) and human papillomavirus (HPV) have been implicated in the aetiology of human breast cancer. We report the presence of HPV DNA sequences in areolar tissue and tumour tissue samples from female patients with breast carcinoma. The presence of virus in the areolar-nipple complex suggests to us a potential pathogenic mechanism.

METHODS

Polymerase chain reaction (PCR) was undertaken to amplify HPV types in areolar and tumour tissue from breast cancer cases. In situ hybridisation supported the PCR findings and localised the virus in nipple, areolar and tumour tissue.

RESULTS

Papillomavirus DNA was present in 25 of 29 samples of breast carcinoma and in 20 of 29 samples from the corresponding mamilla. The most prevalent type in both carcinomas and nipples was HPV 11, followed by HPV 6. Other types detected were HPV 16, 23, 27 and 57 (nipples and carcinomas), HPV 20, 21, 32, 37, 38, 66 and GA3-1 (nipples only) and HPV 3, 15, 24, 87 and DL473 (carcinomas only). Multiple types were demonstrated in seven carcinomas and ten nipple samples.

CONCLUSIONS

The data demonstrate the occurrence of HPV in nipple and areolar tissues in patients with breast carcinoma. The authors postulate a retrograde ductular pattern of viral spread that may have pathogenic significance.

Human papillomavirus and extragenital in situ carcinoma

BACKGROUND

The relation between human papillomavirus (HPV) and extragenital Bowen's disease (BD) is controversial.

METHODS

This study used in situ hybridisation to evaluate the rate of HPV in extragenital cutaneous BD and investigated possible relations with immune status and exposure of skin to light.

RESULTS

HPV DNA was detected in 58% of 69 samples from 50 patients. The percentage of HPV detection was not significantly higher in exposed (55%) than unexposed areas (65%), and no difference in HPV rate was found between immunosuppressed and immunocompetent patients.

CONCLUSION

Thus, this study confirms the high rate of HPV detection in extragenital cutaneous BD and suggests that there is no apparent relation concerning exposed areas and immune status.

UV-B irradiation stimulates the promoter activity of the high-risk, cutaneous human papillomavirus 5 and 8 in primary keratinocytes

Human papillomaviruses (HPV) have been implicated in the development of non-melanoma skin cancer (NMSC). HPV types 5 and 8 are strongly associated with NMSC in patients with the inherited disease Epidermodysplasia verruciformis (Ev). In these patients tumours arise predominantly on sun-exposed skin and consistently harbour HPV DNAs. To determine whether UV-B irradiation modulates the noncoding region (NCR) promoter activity of the Ev-HPV types 5, 8, 9, 14, 23, 24, and 25 we performed transient transfection assays with NCR luciferase reporter gene constructs in primary human epithelial keratinocytes (PHEKs) and in p53-null RTS3b cells. Each of the HPVs showed different basal NCR activity in both cell types and reacted differently upon UVB treatment and p53 cotransfection in RTS3b cells. The NCR of HPV5 and 8 were the only ones to be activated by UV-B in PHEKs. The stimulation of the NCR activity of the high-risk cutaneous HPV types 5 and 8 by UV-B irradiation may point to a role of this interaction in the development of NMSC.

Human papillomavirus type 77 E6 protein selectively inhibits p53-dependent transcription of proapoptotic genes following UV-B irradiation

DNA damage, such as that elicited by UV-B, can induce either a cell cycle arrest or apoptosis that can be signalled by the p53 protein through the activation of a number of downstream cellular target genes. In contrast to oncogenic anogenital human papillomaviruses (HPVs), which mediate proteolytic degradation of p53, the E6 protein of cutaneous HPVs, such as HPV 77, do not promote p53 degradation. We have previously shown, however, that expression of HPV 77 E6 can effectively block UV-induced apoptosis in cells that have UV-activated p53. Here, we report that expression of the E6 protein from the cutaneous HPV 77 attenuates the UV-induced transactivation of p53-regulated proapoptotic genes Fas, PUMAbeta, Apaf-1, PIG3. This inhibition of p53-activation of proapoptotic genes by HPV77 E6 is exerted selectively, as the increased expression of p53 target genes involved in cell cycle arrest or regulatory functions regulation, such as p21 and Hdm2, is unaffected. Our data suggest that HPV 77 E6 may play an important role in specifically deregulating p53-dependent transactivation of proapoptotic genes upon UV-B irradiation.

Repair of UV-induced thymine dimers is compromised in cells expressing the E6 protein from human papillomaviruses types 5 and 18

Ultraviolet (UV) irradiation is a major mutagenic environmental agent, causing the appearance of DNA adducts that, if unrepaired, may give rise to mutations. Ultraviolet radiation has been indicated as a major risk factor in the development of nonmelanoma skin cancers; however, recent reports have suggested that infections with human papillomaviruses, a widespread family of epitheliotropic DNA viruses, may also contribute to the tumorigenic process. Here, we investigated whether expression of the E6 protein from different HPV types interfere with the repair of thymine dimers caused by UV-B radiation. Results show that unrepaired DNA damage can be observed in UV-B-irradiated cells expressing the E6 protein of HPV types found in cervical and epithelial cancers. Moreover, such cells have the ability to overcome the G(1) cell cycle checkpoint induced as a result of unrepaired DNA.

Increased risk of skin cancer associated with the presence of epidermodysplasia verruciformis human papillomavirus types in normal skin

BACKGROUND

Human papillomaviruses (HPVs) are found in normal skin and in benign and malignant skin conditions. Epidermodysplasia verruciformis (EV) HPV types are those most plausibly linked to the development of squamous cell carcinomas of the skin.

OBJECTIVES

To assess the risk of nonmelanoma skin cancer (NMSC) associated with the presence of EV HPV in normal skin in immunocompetent (IC) individuals and renal transplant recipients (RTRs).

METHODS

Using a degenerate and nested polymerase chain reaction technique, HPV DNA was sought in 124 normal skin samples from sun-exposed and nonsun-exposed sites, from 39 IC individuals and 38 RTRs, both with and without NMSC. Data were analysed using the Mantel-Haenszel test and by logistic regression analysis.

RESULTS

HPV DNA was detected in 58/67 (87%) and 20/57 (35%) samples from renal transplant and IC patients, respectively. There was no difference in either the prevalence or spectrum of HPV types found in sun-exposed and nonsun-exposed normal skin. However, there was significant association between NMSC and the presence of EV HPV DNA. Multivariate analysis provided an odds ratio of 6.41 (95% confidence interval 1.79-22.9) for the association of EV HPV DNA in normal skin (irrespective of site) and NMSC status, even after stratifying for patient group and adjusting for the clustering effect of multiple sampling. Conversely, there was no association between skin cancer status and the presence of cutaneous or mucosal HPV types in either sun-exposed or nonsun-exposed skin.

CONCLUSIONS

HPV DNA is widespread in normal adult skin, particularly in transplant patients. In our study, the presence of EV but not cutaneous HPV DNA in normal skin was significantly associated with NMSC status and may prove to be of predictive value for skin cancer risk. These data provide reason to focus on EV HPV types as causal agents in skin cancer.

Human papillomavirus type 2 in a squamous cell carcinoma of the finger

BACKGROUND

Human papillomavirus (HPV) type 2 is generally considered to be a benign viral infection associated with common warts. Other HPV types have been associated with the development of squamous cell carcinomas (SCCs).

OBJECTIVE

To describe a case of HPV type 2 identified in a SCC of the finger in an immunocompetent patient. To our knowledge, this is the first such case reported in the literature.

METHODS

This is a case report and review of the literature.

RESULTS

Mohs micrographic surgery performed in two stages effectively removed the tumor.

CONCLUSION

HPV type 2 may play a role in the development of cutaneous SCC. Further epidemiologic and molecular studies of HPV and SCCs will be helpful in determining the role of HPV type 2 in cutaneous oncogenesis.

Mucosally-derived HPV-40 can infect both human genital foreskin and cutaneous hand skin tissues grafted into athymic mice

HPV-40 is a rare HPV type that has been detected only in genital mucosal tissues. This HPV type is very closely related to HPV-7, which has a predominantly cutaneous tissue tropism. We have shown, previously, that an isolate of HPV-40 (described here as HPV-40(Hershey) or HPV-40(H)) productively infected genital tissues. In this study, HPV-40(H) was tested for productive infection of cutaneous tissue. Fetal hand skin fragments were incubated with infectious HPV-40(H) and implanted subrenally into athymic mice. After 120 days, xenografts showed morphological changes consistent with HPV-40(H) infection and were HPV-40 DNA in situ positive and capsid antigen positive. The results demonstrated that hand skin can support HPV-40(H) infection thereby indicating that this viral type has the capacity to infect both genital mucosal and cutaneous tissues.

Healthy skin of many animal species harbors papillomaviruses which are closely related to their human counterparts

Papillomaviruses associated with clinical symptoms have been found in many vertebrate species. In this study, we have used an L1 gene consensus PCR test designed to detect a broad spectrum of human skin papillomaviruses to analyze swab samples from healthy skin of 111 animals belonging to 19 vertebrate species. In eight of the species, papillomavirus DNA was found with the following prevalences: chimpanzees, 9 of 11 samples positive; gorillas, 3 of 4; long-tailed macaques, 14 of 16; spider monkeys, 2 of 2; ruffed lemurs, 1 of 2; cows, 6 of 10; European elks, 4 of 4; aurochs, 1 of 1. In total, 53 new putative animal papillomavirus types were found. The results show that skin papillomaviruses can be detected in healthy skin from many different animal species and are sufficiently related genetically to their human counterparts to be identified by a human skin papillomavirus primer set (FAP59 and FAP64).

Human papillomaviruses and non-melanoma skin cancer

Epidemiological and experimental studies have overwhelmingly confirmed human papillomaviruses as important causal agents in anogenital carcinogenesis. A role for human papillomaviruses has also been proposed in a diverse range of other malignancies, and particular interest has focused on non-melanoma skin cancer, the commonest malignancy in fair-skinned populations worldwide. Although the evidence for this is considerably less convincing than for anogenital cancer, important epidemiological and functional data have emerged over the past year that have furthered our understanding of the possible contribution of human papillomaviruses to skin cancer. Epidemiological human papillomavirus DNA detection studies have shown associations with non-melanoma skin cancer, but have also emphasized the ubiquity of epidermodysplasia verruciformis human papillomavirus types in normal skin, hair follicles and benign hyperproliferative disorders, as have seroepidemiological approaches. Functional investigations have demonstrated mechanistically relevant interactions between the virus and ultraviolet radiation, host cytokines and cellular proteins including p53 and the pro-apoptotic protein Bak. Taken together, these data have advanced our understanding of the contribution of human papillomaviruses to malignant transformation in cutaneous keratinocytes, but further research is required before a causal association between human papillomaviruses and skin cancer is reliably confirmed.

Human papillomavirus and skin cancer

Human papillomavirus (HPV) appears to be the most ubiquitous of the human viruses. Over 100 HPV types have been identified. A minority of HPV cause cutaneous warts and mucosal condylomata. The HPV that cause mucosal condylomata put the patient at various degrees of risk for developing cancers, particularly cervical cancer. The majority of HPV infect the skin of normal and immunocompromised individuals. In normal people, most of these HPV appear to establish a latent infection of the skin, most likely as normal flora residing in hair follicles; however, in patients with various systemic and localized depressions of cell-mediated immunity, some HPV infections appear to be involved in the development of nonmelanotic skin cancer and its precursor lesions in skin, usually in sunlight-exposed areas. Circumstantial evidence suggests that these HPV may have a role in promoting proliferative lesions of the skin, although their sites of active infection and mode of transmission to susceptible individuals remain unknown.

Opposite regulation of the HPV 20-URR and HPV 27-URR promoters by ultraviolet irradiation and cytokines

Epidemiological evidence implicates ultraviolet radiation and genetic changes (e.g., p53 mutations) as important factors in the etiology of nonmelanoma skin cancer. Little is known about a possible role of cutaneous papillomaviruses in these tumors. We previously reported both positive and negative regulation of the promoter activity of a number of HPV types by UV irradiation. To determine the underlying mechanism, we examined the influence of pro-inflammatory cytokines and MAP-kinases induced by UV irradiation by transfecting the HPV 20-URR and the HPV 27-URR into the RKO, HaCaT and H1299 cell lines expressing wild-type or mutated p53 or lacking p53, respectively. IL-1alpha, IL-1beta, IL-6, IL-17, TNF-alpha, as well as interferon-alpha, -beta and -gamma activated the promoter in the HPV 20-URR but inhibited the HPV 27-URR promoter. The effect of IL-1alpha and UV light was abolished by the addition of IL-1 receptor antagonist. UV irradiation induced a prolonged activation of JNK in HaCaT and H1299 but not in RKO cells, and its dephosphorylation was enhanced in the presence of p53 and the HPV-URRs.

The ubiquity and impressive genomic diversity of human skin papillomaviruses suggest a commensalic nature of these viruses

Human papillomaviruses (HPV) are epitheliotropic viruses, with some types suggested to be associated with skin cancer. In this study, swab samples collected from five different sites on the skin of renal transplant recipients, dialysis patients, and age- and sex-matched healthy controls were analyzed for HPV DNA by a newly designed PCR test. Most individuals were found to have asymptomatic HPV infections; more specifically, 94% of the renal transplant patients, 82% of the dialysis patients, and 80% of the healthy controls were positive for HPV DNA. The multiplicity of the HPVs detected was astounding: 20 previously described and 30 putatively new types were identified by cloning and sequencing of 33 samples from 13 individuals. These results demonstrate that normal human skin harbors an array of papillomaviruses, most of them previously unknown.