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

Microhomology-mediated repair machinery and its relationship with HPV-mediated oncogenesis

Human Papillomaviruses (HPV) are a diverse family of non-enveloped dsDNA viruses that infect the skin and mucosal epithelia. Persistent HPV infections can lead to cancer frequently involving integration of the virus into the host genome, leading to sustained oncogene expression and loss of capsid and genome maintenance proteins. Microhomology-mediated double-strand break repair, a DNA double-stranded breaks repair pathway present in many organisms, was initially thought to be a backup but it's now seen as vital, especially in homologous recombination-deficient contexts. Increasing evidence has identified microhomology (MH) near HPV integration junctions, suggesting MH-mediated repair pathways drive integration. In this comprehensive review, we present a detailed summary of both the mechanisms underlying MH-mediated repair and the evidence for its involvement in HPV integration in cancer. Lastly, we highlight the involvement of these processes in the integration of other DNA viruses and the broader implications on virus lifecycles and host innate immune response.

Human Papillomavirus-Associated Giant Clear Cell Acanthoma and Squamous Cell Carcinoma: A Rare Case Report and Literature Review

Clear cell acanthoma (CCA) and squamous cell carcinoma (SCC) represent distinct entities within dermatological oncology, each posing unique diagnostic and therapeutic challenges. CCA is a rare, benign epidermal growth, often not associated with human papillomavirus (HPV) infection, whereas SCC, a more aggressive form of skin cancer, has been linked to both ultraviolet (UV) exposure and HPV. Understanding the co-occurrence of these conditions in a single patient can enhance diagnostic accuracy and therapeutic outcomes. We report a 64-year-old male who underwent an operation for a verruciform lesion in the right groin, which was diagnosed as HPV-positive CCA alongside keratinised SCC. A literature search across January 2024 revealed limited evidence directly linking HPV to CCA, suggesting a need for further investigation. The speculative association between HPV and CCA warrants deeper exploration, especially considering the potential for HPV to contribute to lesion development through indirect mechanisms. The coexistence of CCA and SCC in an elderly patient presents a unique clinical scenario. This emphasises the need for vigilant diagnosis and tailored treatment strategies, highlighting the gap in understanding the pathogenesis of CCA, particularly its potential association with HPV. Further research is crucial for elucidating the complex interactions governing these conditions and for developing targeted interventions.

Rubella virus chronic inflammatory disease and other unusual viral phenotypes in inborn errors of immunity

Infectious susceptibility is a component of many inborn errors of immunity. Nevertheless, antibiotic use is often used as a surrogate in history taking for infectious susceptibility, thereby disadvantaging patients who present with viral infections as their phenotype. Further complicating clinical evaluations are unusual manifestations of viral infections which may be less familiar that the typical respiratory viral infections. This review covers several unusual viral phenotypes arising in patients with inborn errors of immunity and other settings of immune compromise. In some cases, chronic infections lead to oncogenesis or tumor-like growths and the conditions and mechanisms of viral-induced oncogenesis will be described. This review covers enterovirus, rubella, measles, papillomavirus, and parvovirus B19. It does not cover EBV and hemophagocytic lymphohistiocytosis nor lymphomagenesis related to EBV. EBV susceptibility has been recently reviewed. Our goal is to increase awareness of the unusual manifestations of viral infections in patients with IEI and to describe treatment modalities utilized in this setting. Coincidentally, each of the discussed viral infections can have a cutaneous component and figures will serve as a reminder of the physical features of these viruses. Given the high morbidity and mortality, early recognition can only improve outcomes.

Metagenomic search of viral coinfections in herpes simplex encephalitis patients

Little is known about concomitant central nervous system (CNS) infections by more than one virus. Current diagnostics are based on molecular tests for particular pathogens making it difficult to identify multi-viral infections. In the present study, we applied DNA- and RNA-based next-generation sequencing metagenomics (mNGS) to detect viruses in cerebrospinal fluids from 20 patients with herpes simplex encephalitis. Coinfection was detected in one patient: sequences in cerebrospinal fluids matched enterovirus A (2.660 reads; 4% of recovered genome) and enterovirus B (1.571 reads; 13% of recovered genome). Subsequent PCR combined with serotyping allowed to identify human echovirus 6, a representative of enterovirus B. Several other mNGS hits (human pegivirus, Merkel cell polyomavirus, human papillomavirus type 5) were not considered to represent a genuine signal as they could not be confirmed by specific RT-PCR/PCR. HSV DNA, while being detectable by PCR in every patient, was detected by mNGS in only one. In conclusion, contaminations and false signals may complicate mNGS interpretation; however, the method can be useful in diagnostics of viral coinfections in CNS, particularly in the case of rare pathogens.

Therapeutic strategy for oncovirus-mediated oral cancer: A comprehensive review

Oral cancer is a neoplastic disorder of the oral cavities, including the lips, tongue, buccal mucosa, and lower and upper gums. Oral cancer assessment entails a multistep process that requires deep knowledge of the molecular networks involved in its progression and development. Preventive measures including public awareness of risk factors and improving public behaviors are necessary, and screening techniques should be encouraged to enable early detection of malignant lesions. Herpes simplex virus (HSV), human papillomavirus (HPV), Epstein-Barr virus (EBV), and Kaposi sarcoma-associated herpesvirus (KSHV) are associated with other premalignant and carcinogenic conditions leading to oral cancer. Oncogenic viruses induce chromosomal rearrangements; activate signal transduction pathways via growth factor receptors, cytoplasmic protein kinases, and DNA binding transcription factors; modulate cell cycle proteins, and inhibit apoptotic pathways. In this review, we present an up-to-date overview on the use of nanomaterials for regulating viral proteins and oral cancer as well as the role of phytocompounds on oral cancer. The targets linking oncoviral proteins and oral carcinogenesis were also discussed.

Condyloma and coincidental epidermodysplasia verruciformis acanthoma positive for human papillomavirus-14 and -21

Epidermodysplasia verruciformis (EDV) is a rare genodermatosis that predisposes individuals to persistent infection with β-human papillomavirus (HPV) genotypes. The term EDV acanthoma may be applied to lesions with incidental findings of EDV-defining histopathological features without clinical signs of EDV. We report a case of HPV-14- and -21-positive EDV acanthoma arising in association with condyloma in a female patient with a history of low-grade squamous intraepithelial lesion of the cervix positive for high-risk HPV (non-16/18), chronic kidney disease, and systemic lupus erythematosus. The patient had no family or personal history of EDV, but the patient was on immunosuppressive therapy with mycophenolate mofetil and prednisone. A biopsy specimen from one of the perianal lesions revealed histopathologic changes consistent with EDV in the setting of condyloma. Molecular testing showed HPV-14 and -21, which supported the coexistence of condyloma with EDV acanthoma.

Factors mediating cancer risk in systemic lupus erythematosus

Patients with systemic lupus erythematosus (SLE) are at an elevated risk for certain cancers compared to the population at large. Cancers seen at higher rates in the SLE population include hematologic malignancies, such as non-Hodgkin lymphoma, and cancers of the lung and thyroid. SLE patients also have a decreased risk for certain malignancies, such as breast cancer, melanoma, and prostate cancer. We review the literature on risk factors for malignancy in patients with SLE and discuss the exogenous and innate factors that are thought to contribute to the unique pattern of cancer risk observed in this patient population. These risk factors are important for providers of SLE patients to understand in order to maintain high clinical suspicion and detect malignancy as soon as possible. Further research is needed to determine the most effective guidelines on counseling patients on cancer screening and prevention.

Cervical dysplasia in a patient with inherited epidermodysplasia verruciformis-A mere coincidence?

Epidermodysplasia verruciformis (EV) is a rare inherited or acquired genodermatosis caused by increased susceptibility to infection by the beta subtypes of human papillomavirus (HPV). The co-occurrence of EV with high-risk (HR) HPV infection leading to cervical dysplasia is unreported in the literature to date. We report a patient with inherited EV who developed extensive anogenital and cervical dysplasia linked to concurrent HR-HPV infection. Literature review suggests that there is a negative correlation of cervical dysplasia and cervical cancer with EV, which suggests that this patient's presentation and course are exceptional.

Sebaceous Carcinoma Epidemiology and Genetics: Emerging Concepts and Clinical Implications for Screening, Prevention, and Treatment

Sebaceous carcinoma is an aggressive skin cancer with a 5-year overall survival rate of 78% for localized/regional disease and 50% for metastatic disease. The incidence of this cancer has been increasing in the United States for several decades, but the underlying reasons for this increase are unclear. In this article, we review the epidemiology and genetics of sebaceous carcinoma, including recent population data and tumor genomic analyses that provide new insights into underlying tumor biology. We further discuss emerging evidence of a possible viral etiology for this cancer. Finally, we review the clinical implications of recent advances in sebaceous carcinoma research for screening, prevention, and treatment.

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.

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.

Diagnosis of epidermodysplasia verruciformis: Two cases highlighting the role of direct HPV L1 gene sequencing

Epidermodysplasia verruciformis (EV) is a rare skin disease characterized by the development of multiple flat warts with the potential for malignant transformation. Patients are susceptible to human papillomavirus (HPV) infection that develops in a background of either a genetic or acquired immunodeficiency predisposing patients to infection with specific HPV types that are ubiquitous but generally non-pathogenic in healthy individuals. There is no standard clinical methodology for determining the causative HPV from patients with suspected EV. Here, we report the diagnostic workup of two EV cases and describe the use of L1 gene Sanger sequencing as a specific method to accurately identify the causative HPV genotype and confirm the diagnosis of EV.

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.

The Role of Human Papillomaviruses and Polyomaviruses in BRAF-Inhibitor Induced Cutaneous Squamous Cell Carcinoma and Benign Squamoproliferative Lesions

Background: Human papillomavirus (HPV) has long been proposed as a cofactor in the pathogenesis of cutaneous squamous cell carcinoma (cSCC). More recently, the striking clinico-pathological features of cSCCs that complicate treatment of metastatic melanoma with inhibitors targeting BRAF mutations (BRAFi) has prompted speculation concerning a pathogenic role for oncogenic viruses. Here, we investigate HPV and human polyomaviruses (HPyV) and correlate with clinical, histologic, and genetic features in BRAFi-associated cSCC.

Materials and Methods: Patients receiving BRAFi treatment were recruited at Barts Health NHS Trust. HPV DNA was detected in microdissected frozen samples using reverse line probe technology and degenerate and nested PCR. HPV immunohistochemistry was performed in a subset of samples. Quantitative PCR was performed to determine the presence and viral load of HPyVs with affinity for the skin (HPyV6, HPyV7, HPyV9, MCPyV, and TSPyV). These data were correlated with previous genetic mutational analysis of H, K and NRAS, NOTCH1/2, TP53, CDKN2A, CARD11, CREBBP, TGFBR1/2. Chromosomal aberrations were profiled using single nucleotide polymorphism (SNP) arrays.

Results: Forty-five skin lesions from seven patients treated with single agent vemurafenib in 2012–2013 were analyzed: 12 cSCC, 19 viral warts (VW), 2 actinic keratosis (AK), 5 verrucous keratosis/other squamoproliferative (VK/SP) lesions, one melanocytic lesion and 6 normal skin samples. Significant histologic features of viral infection were seen in 10/12 (83%) cSCC. HPV DNA was detected in 18/19 (95%) VW/SP, 9/12 (75%) cSCC, 4/5 (80%) SP, and 3/6 (50%) normal skin samples and in 1/12 cases assessed by immunohistochemistry. HPyV was co-detected in 22/30 (73%) of samples, usually at low viral load, with MCPyV and HPyV7 the most common. SNP arrays confirmed low levels of chromosomal abnormality and there was no significant correlation between HPV or HPyV detection and individual gene mutations or overall mutational burden.

Conclusion: Despite supportive clinicopathologic evidence, the role for HPV and HPyV infection in the pathogenesis of BRAFi-induced squamoproliferative lesions remains uncertain. Synergistic oncogenic mechanisms are plausible although speculative. Nonetheless, with the prospect of a significant increase in the adjuvant use of these drugs, further research is justified and may provide insight into the pathogenesis of other BRAFi-associated malignancies.

Human papillomavirus-associated cutaneous disease burden in human immunodeficiency virus (HIV)-positive patients: the role of human papillomavirus vaccination and a review of the literature

Human papillomavirus (HPV) infection is related to the development of cutaneous squamous cell carcinoma, oropharyngeal carcinoma, and anogenital malignancies. Patients infected with human immunodeficiency virus (HIV) have impaired cell-mediated immunity, placing them at risk for more prolonged infection with a greater likelihood of disease expression. This presents important implications for screening and treatment of HPV in the HIV patient population. The use of prophylactic vaccines directed against HPV has been a promising clinical development, though the immunogenicity of these vaccines in the immunocompromised host and in patients with previously established HPV infections has not been well established. In this review, we describe the pathogenesis and epidemiology of HPV-related cutaneous malignancies in patients with HIV. We outline the current guidelines and recent advances in the field of HPV vaccination. It is our hope that increasing awareness of the HPV-related HIV comorbidities will lead to developments in preventative medicine capable of reducing the burden of these diseases. We recognize the importance of prevention as a primary defense against disease and hope that this article organizes and disseminates recent findings in the field of HPV-associated comorbidities in the HIV population.

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.

A programme of research to set priorities and reduce uncertainties for the prevention and treatment of skin disease

Background

Skin diseases are very common and can have a large impact on the quality of life of patients and caregivers. This programme addressed four diseases: (1) eczema, (2) vitiligo, (3) squamous cell skin cancer (SCC) and (4) pyoderma gangrenosum (PG).

Objective

To set priorities and reduce uncertainties for the treatment and prevention of skin disease in our four chosen diseases.

Design

Mixed methods including eight systematic reviews, three prioritisation exercises, two pilot randomised controlled trials (RCTs), three feasibility studies, two core outcome initiatives, four funding proposals for national RCTs and one completed national RCT.

Setting

Secondary care, primary care and the general population.

Participants

Patients (and their caregivers) with eczema, vitiligo, SCC and PG, plus health-care professionals with an interest in skin disease.

Interventions

Our three intervention studies included (1) barrier enhancement using emollients from birth to prevent eczema (pilot RCT); (2) handheld narrowband ultraviolet light B therapy for treating vitiligo (pilot RCT); and (3) oral ciclosporin (Neoral®, Novartis Pharmaceuticals) compared with oral prednisolone for managing PG (pragmatic national RCT).

Results

Systematic reviews included two overarching systematic reviews of RCTs of treatments for eczema and vitiligo, an umbrella review of systematic reviews of interventions for the prevention of eczema, two reviews of treatments for SCC (one included RCTs and the second included observational studies), and three reviews of outcome measures and outcome reporting. Three prioritisation partnership exercises identified 26 priority areas for future research in eczema, vitiligo and SCC. Two international consensus initiatives identified four core domains for future eczema trials and seven core domains for vitiligo trials. Two pilot RCTs and three feasibility studies critically informed development of four trial proposals for external funding, three of which are now funded and one is pending consideration by funders. Our pragmatic RCT tested the two commonly used systemic treatments for PG (prednisolone vs. ciclosporin) and found no difference in their clinical effectiveness or cost-effectiveness. Both drugs showed limited benefit. Only half of the participants’ ulcers had healed by 6 months. For those with healed ulcers, recurrence was common (30%). Different side effect profiles were noted for each drug, which can inform clinical decisions on an individual patient basis. Three researchers were trained to PhD level and a dermatology patient panel was established to ensure patient involvement in all aspects of the programme.

Conclusions

Findings from this programme of work have already informed clinical guidelines and patient information resources. Feasibility studies have ensured that large national pragmatic trials will now be conducted on important areas of treatment uncertainty that address the needs of patients and the NHS. There is scope for considerable improvement in terms of trial design, conduct and reporting for RCTs of skin disease, which can be improved through wider collaboration, registration of trial protocols and complete reporting and international consensus over core outcome sets. Three national trials have now been funded as a result of this work. Two international initiatives to establish how best to measure the core outcome domains for eczema and vitiligo are ongoing.

Trial registration

Current Controlled Trials Barrier Enhancement for Eczema Prevention (BEEP) (ISRCTN84854178 and NCT01142999), Study of Treatments fOr Pyoderma GAngrenosum Patients (STOP GAP) (ISRCTN35898459) and Hand Held NB-UVB for Early or Focal Vitiligo at Home (HI-Light Pilot Trial) (NCT01478945).

Funding

This project was funded by the National Institute for Health Research (NIHR) Programme Grants for Applied Research programme and will be published in full inProgramme Grants for Applied Research; Vol. 4, No. 18. See the NIHR Journals Library website for further project information.

[Infectious and neoplasic complications after kidney transplantation]

Infections and malignancies are the expected complications of immunosuppressive therapy, which non-specifically impairs cellular and humoral immune responses in renal transplant recipients. Infections were usually frequent and severe during the early post-transplant period (first year). Recent diagnostic methods (molecular biology) and availability of new antivirals, antifungal and antibiotic drugs made rapid diagnosis and systematic preventive strategies much easier and this resulted in a significant reduction of infections and infectious death in this population. However, new infectious agents like BK polyomavirus, hepatitis E virus, parvovirus (as well as Chigunkunya, West Nile and others in particular areas) were recently recognized as responsible of aggressive infections in the immunocompromised host. Malignancies are also common after transplantation, due to the intensity and duration of immunosuppression. Skin cancers and lymphoproliferative disorders are the most common and are undoubtedly caused by viral infections, but incidence of non-skin cancers is also increased. After reduction of immunosuppression, treatment is similar to non-transplant patients: Results are usually poor and cancer is now the third cause of death in transplant recipients. Due to their anti-proliferative and anti-tumoral properties, incidence of de novo cancer significantly decreased in patients receiving mTor inhibitors as maintenance immunosuppression; furthermore, in patients already diagnosed with Kaposi sarcoma or recurrent skin cancers, introduction of mTor was associated with stabilisation and/or regression of malignant lesions.

Human papillomavirus detected in viral warts of renal transplant recipients

OBJECTIVES

Few studies have been conducted in South America regarding the detection and genotyping of human papillomavirus (HPV) in viral warts of renal transplant recipients (RTRs). The characterization of the population most susceptible to the development of warts and the knowledge of the main HPV types in this environment prompted this study, which focuses on the detection and typing of HPV in RTRs in Brazil.

METHODS

Fifty-eight patients with viral warts from the Hospital São Paulo/Federal University of São Paulo were included in this study. HPV was detected by polymerase chain reaction (PCR) using combinations of the following primers: PGMY 09/11, RK 91, CP 65/70, and CP 66/69. Restriction fragment length polymorphism and automated sequencing techniques were used for HPV typing.

RESULTS

HPV was detected by PCR in 89.7% of viral wart samples. The most frequently detected HPV types included 57, 27, 1a, 2a, and 20. Other types of HPV-epidermodysplasia verruciformis were also detected, including 14, 15, 19, 20, 21, 23, 36, and 38. Rare HPV types were also detected in our environment, including RTR X1, RTR X7, and 100. The time after transplant was correlated with an increased number of lesions and beta papillomavirus genus infection.

CONCLUSIONS

The HPV types detected in the RTR population were similar to those described in immunocompetent populations. However, the diversity of the HPV types identified and the number of lesions were increased in the RTR population.

HPV vaccination for prevention of skin cancer

Cutaneous papillomaviruses are associated with specific skin diseases, such as extensive wart formation and the development of non-melanoma skin cancer (NMSC), especially in immunosuppressed patients. Hence, clinical approaches are required that prevent such lesions. Licensed human papillomavirus (HPV) vaccines confer type-restricted protection against HPV types 6, 11, 16 and 18, responsible of 90% of genital warts and 70% of cervical cancers, respectively. However, they do not protect against less prevalent high-risk types or cutaneous HPVs. Over the past few years, several studies explored the potential of developing vaccines targeting cutaneous papillomaviruses. These vaccines showed to be immunogenic and prevent skin tumor formation in certain animal models. Furthermore, under conditions mimicking the ones found in the intended target population (i.e., immunosuppression and in the presence of an already established infection before vaccination), recent preclinical data shows that immunization can still be effective. Strategies are currently focused on finding vaccine formulations that can confer protection against a broad range of papillomavirus-associated diseases. The state-of-the-art of these approaches and the future directions in the field will be presented.

Cancer prevention in HIV-infected populations

People living with human immunodeficiency virus (HIV) are living longer since the advent of effective combined antiretroviral therapy (cART). While cART substantially decreases the risk of developing some cancers, HIV-infected individuals remain at high risk for Kaposi sarcoma, lymphoma, and several solid tumors. Currently HIV-infected patients represent an aging group, and malignancies have become a leading cause of morbidity and mortality. Tailored cancer-prevention strategies are needed for this population. In this review we describe the etiologic agents and pathogenesis of common malignancies in the setting of HIV, as well as current evidence for cancer prevention strategies and screening programs.

Plexin-B1 and semaphorin 4D cooperate to promote cutaneous squamous cell carcinoma cell proliferation, migration and invasion

BACKGROUND OBJECTIVES

Semaphorin 4D (Sema4D) and its receptor, Plexin-B1, are involved in the pathogenesis of squamous cell carcinoma (SCC) by mediating angiogenesis or perineural invasion through the interaction between Sema4D expression on SCC cells and Plexin-B1 expression on endothelial cells or nerves. Plexin-B1 was also recently found to be expressed on SCC cells. Plexin-B1 expression on several types of tumor cells could mediate various, and occasionally opposing, effects, including tumor cell survival, proliferation, angiogenesis, invasion, and metastasis. However, whether Sema4D exerts paracrine or autocrine effects on SCC via Plexin-B1 remains unclear.

OBJECTIVES

The aim of this study is to explore the effects of Sema4D/Plexin-B1 interaction on SCC via Plexin-B1 expressed on the tumor cells.

METHODS

In the present study, we detected the expression of Plexin-B1 and Sema4D in cutaneous SCC (cSCC) tissues and in the cSCC cell line A431 and analyzed the effects of the Sema4D/Plexin-B1 interaction on cSCC cell proliferation, migration, and invasion, as well as on the signaling pathway downstream of Plexin-B1.

RESULTS

We observed significantly increased Plexin-B1 and Sema4D expression in keratinocytes in cSCC lesions and in A431 cells compared with that in normal skin tissue and in non-malignant keratinocytes. Plexin-B1 silencing reduced the growth, proliferation, migration, and invasion of A431 cells and inhibited the phosphorylation of Akt and extracellular signal-regulated protein kinase (Erk). Soluble recombinant Sema4D promoted the growth, proliferation, migration, and invasion of A431 cells; Akt and Erk phosphorylation is also involved in these processes with a Plexin-B1 dependent manner.

CONCLUSION

Plexin-B1 induces cSCC cell proliferation, migration, and invasion by interacting with Sema4D. Plexin-B1 might serve as a useful biomarker and/or as a novel therapeutic target for cSCC.

Disruption of Bcl-2 and Bcl-xL by viral proteins as a possible cause of cancer

The Bcl proteins play a critical role in apoptosis, as mutations in family members interfere with normal programmed cell death. Such events can cause cell transformation, potentially leading to cancer. Recent discoveries indicate that some viral proteins interfere with Bcl proteins either directly or indirectly; however, these data have not been systematically described. Some viruses encode proteins that reprogramme host cellular signalling pathways controlling cell differentiation, proliferation, genomic integrity, cell death, and immune system recognition. This review analyses and summarises the existing data and discusses how viral proteins interfere with normal pro- and anti-apoptotic functions of Bcl-2 and Bcl-xL. Particularly, this article focuses on how viral proteins, such as Herpesviruses, HTLV-1, HPV and HCV, block apoptosis and how accumulation of such interference predisposes cancer development. Finally, we discuss possible ways to prevent and treat cancers using a combination of traditional therapies and antiviral preparations that are effective against these viruses.

Resistance to UV-induced apoptosis by β-HPV5 E6 involves targeting of activated BAK for proteolysis by recruitment of the HERC1 ubiquitin ligase

UV exposure is the main etiological agent in the development of non-melanoma skin cancer (NMSC), but mounting evidence suggests a co-factorial role for β-genus HPV types early in tumor initiation or progression. UV damage initiates an apoptotic response, driven at the mitochondrial level by BCL-2 family proteins, that eliminates damaged cells that may accumulate deleterious mutations and acquire tumorigenic properties. BAK is a pro-apoptotic BCL-2 protein that functions ultimately to form pores that permeabilize the mitochondrial outer membrane, thereby committing a cell to death, a process involving changes in BAK phosphorylation and conformation. The E6 protein of β-type HPV5 signals BAK for proteasomal degradation, a function that confers protection from UV-induced apoptosis. We find that HPV5 E6 does not constitutively target BAK for proteolysis, but targets the latter stages of BAK activation, following changes in phosphorylation and conformation. A mutational analysis identified the lysine residue on BAK required for proteolysis, and a functional siRNA screen identified the HECT domain E3 ubiquitin ligase HERC1 as being required for E6-mediated BAK degradation. We show that HERC1 interacts with BAK in E6-expressing cells that have been damaged by UV, and provide evidence that the interaction of HERC1 with BAK requires access to a hydrophobic surface on BAK that binds BH3 domains of BCL-2 proteins. We also show that HERC1 contains a putative BH3 domain that can bind to BAK. These findings reveal a specific and unique mechanism used by the HPV5 E6 protein to target BAK.

HLA-C -35kb expression SNP is associated with differential control of β-HPV infection in squamous cell carcinoma cases and controls

A single nucleotide polymorphism (SNP) 35 kb upstream of the HLA-C gene is associated with HLA-C expression, and the high expressing genotype (CC) has been associated with HIV-I control. HLA-C is unique among the classical MHC class I molecules for its role in the control of viral infections and recognition of abnormal or missing self. This immunosurveillance is central to the pathogenesis of non-melanoma skin cancer (NMSC), and of squamous cell carcinoma (SCC) in particular. While sun exposure is a major risk factor for these cancers, cutaneous infections with genus β-HPV have been implicated in the development of SCC. We hypothesized that the high expression HLA-C genotype is associated with β-HPV infections. Therefore, we investigated the association between β-HPV serology and the -35 kb SNP (rs9264942) in a population-based case-control study of 510 SCC cases and 608 controls. Among controls, the high expression -35 kb SNP genotype (CC) reduced the likelihood of positive serology for multiple (≥2) β-HPV infections (OR = 0.49, 95% CI: 0.25-0.97), and β-HPV species 2 infection (OR = 0.43, 95% CI: 0.23-0.79). However, no association with β-HPV status was observed among SCC cases. Our findings suggest that underlying immunogenotype plays an important role in differential control of β-HPV in SCC cases and controls.

Persistent toenail onycholysis associated with Beta-papillomavirus infection of the nail bed

Onycholysis, separation of the nail plate from the nail bed, is etiologically classified as primary (idiopathic) or secondary (eg, caused by psoriasis, squamous cell carcinoma). Repetitive microtrauma plays a role in idiopathic onycholysis and also facilitates human papillomavirus (HPV) infection. Herein, we report a case of persistent primary onycholysis associated with repetitive trauma and infection by a multiplicity of Beta-papillomavirus (Beta-PV) genotypes. An otherwise healthy 27-year-old woman presented with a 6-year history of onycholysis of the halluces and right second toe. Her occupation required wearing steel-toed boots. Fungal cultures were negative and antifungal therapy was ineffective. Punch biopsy of the hallux nail bed revealed epidermal hyperplasia, acanthosis, hypergranulosis, hyperkeratosis, and regions of koilocytosis without significant inflammation. This histopathology implicated chronic irritation and HPV infection. Immunohistochemistry demonstrated productive HPV infection. Nested PCR using degenerate consensus primers revealed infection with 5 known and 1 novel Beta-PV genotypes (HPV 5, HPV 8, HPV 20, HPV 23, HPV 37, and FA25). The histopathology of primary onycholysis is unknown. Based on the aforementioned, we propose that repetitive microtrauma caused by wearing steel-toed boots promoted onycholysis and HPV infection, the latter of which, altered the differentiation of nail bed epithelium, preventing adhesion of nail plate to the nail bed. Lastly, the presence of oncogenic Beta-PV genotypes (ie, HPV 5, 8, and 20) implicates a risk for subungual squamous cell carcinoma, particularly if the nail remains symptomatic and persistently irritated.

DNA cleavage enzymes for treatment of persistent viral infections: recent advances and the pathway forward

Treatment for most persistent viral infections consists of palliative drug options rather than curative approaches. This is often because long-lasting viral DNA in infected cells is not affected by current antivirals, providing a source for viral persistence and reactivation. Targeting latent viral DNA itself could therefore provide a basis for novel curative strategies. DNA cleavage enzymes can be used to induce targeted mutagenesis of specific genes, including those of exogenous viruses. Although initial in vitro and even in vivo studies have been carried out using DNA cleavage enzymes targeting various viruses, many questions still remain concerning the feasibility of these strategies as they transition into preclinical research. Here, we review the most recent findings on DNA cleavage enzymes for human viral infections, consider the most relevant animal models for several human viral infections, and address issues regarding safety and enzyme delivery. Results from well-designed in vivo studies will ideally provide answers to the most urgent remaining questions, and allow continued progress toward clinical application.

A conserved C-terminal sequence of high-risk cutaneous beta-human papillomavirus E6 proteins alters localization and signalling of β1-integrin to promote cell migration

Beta-human papillomaviruses (β-HPV) infect cutaneous epithelia, and accumulating evidence suggests that the virus may act as a co-factor with UV-induced DNA damage in the development and progression of non-melanoma skin cancer, although the molecular mechanisms involved are poorly understood. The E6 protein of cutaneous β-HPV types encodes functions consistent with a role in tumorigenesis, and E6 expression can result in papilloma formation in transgenic animals. The E6 proteins of high-risk α-HPV types, which are associated with the development of anogenital cancers, have a conserved 4 aa motif at their extreme C terminus that binds to specific PDZ domain-containing proteins to promote cell invasion. Likewise, the high-risk β-HPVs HPV5 and HPV8 E6 proteins also share a conserved C-terminal motif, but this is markedly different from that of α-HPV types, implying functional differences. Using binding and functional studies, we have shown that β-HPV E6 proteins target β1-integrin using this C-terminal motif. E6 expression reduced membrane localization of β1-integrin, but increased overall levels of β1-integrin protein and its downstream effector focal adhesion kinase in human keratinocytes. Altered β1-integrin localization due to E6 expression was associated with actin cytoskeleton rearrangement and increased cell migration that was abolished by point mutations in the C-terminal motif of E6. We concluded that modulation of β1-integrin signalling by E6 proteins may contribute towards the pathogenicity of these β-HPV types.

Diversity of human papillomaviruses in skin lesions

Pools of frozen biopsies from patients with squamous cell carcinoma (SCC) (n=29) actinic keratosis (AK) (n=31), keratoacanthoma (n=91) and swab samples from 84 SCCs and 91 AKs were analysed with an extended HPV general primer PCR and high-throughput sequencing of amplimers. We found 273 different HPV isolates (87 known HPV types, 139 previously known HPV sequences (putative types) and 47 sequences from novel putative HPV types). Among the new sequences, five clustered in genus Betapapillomavirus and 42 in genus Gammapapillomavirus. Resequencing of the three pools between 21 to 70 times resulted in the detection of 283 different known or putative HPV types, with 156 different sequences found in only one of the pools. Type-specific PCRs for 37 putative types from an additional 296 patients found only two of these putative types. In conclusion, skin lesions contain a large diversity of HPV types, but most appeared to be rare infections.

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

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

Identification of human papillomavirus type 156, the prototype of a new human gammapapillomavirus species, by a generic and highly sensitive PCR strategy for long DNA fragments

This study developed a hanging-droplet long PCR, a generic and highly sensitive strategy to facilitate the identification of new human papillomavirus (HPV) genomes. This novel procedure used for the first time the hanging-droplet PCR technique for the amplification of long DNA fragments with generic primers targeting the L1 and E1 regions. It was first applied to the amplification of types belonging to the highly divergent genus Gammapapillovirus (γ-PV). The hanging-droplet long PCR was 100-fold more sensitive than a simple long PCR procedure, detecting as few as ten copies of HPV-4. Nineteen skin samples, potentially containing putative HPV types from the γ-PV genus, were also screened. The method identified four γ-PV genomic halves from new and previously described putative types, and made the full characterization of HPV-156 possible. This novel virus meets the criteria for a new species within the γ-PV genus, with nucleotide identities in the L1 ORF ranging from 58.3 to 67.3 % compared with representative types of the current γ-PV species. HPV-156 showed the highest identity to HPV-60 (67.3 %) from species γ-4, and was consistently closely related to it in both late- and early-gene-derived phylogenies. In conclusion, this report provides a versatile and highly sensitive approach that allowed identification of the prototype of a new species within the γ-PV genus. Its application with primers targeting the different genera in which both human and non-human PVs are distributed may facilitate characterization of the missing members of the family Papillomaviridae.

High incidence of potentially virus-induced malignancies in systemic lupus erythematosus: a long-term followup study in a Danish cohort

OBJECTIVE

Patients with systemic lupus erythematosus (SLE) seem to experience an increased prevalence of oncogenic virus infections. The aim of the present study was to investigate whether SLE patients have an increased risk of virus-associated malignancies, defined as malignancies potentially caused by virus infection.

METHODS

A hospital-based cohort of 576 SLE patients was linked to the Danish Cancer Registry. The cohort was followed up for malignancies from the date of SLE diagnosis, and standardized incidence ratios (SIRs) were calculated for various forms of cancer.

RESULTS

The median duration of followup was 13.2 years. Compared to the general population, the patients experienced an increased overall risk of cancer (SIR 1.6 [95% confidence interval (95% CI)] 1.2-2.0). We observed an increased risk of virus-associated cancers combined (SIR 2.9 [95% CI 2.0-4.1]). Among human papillomavirus (HPV)-associated malignant and premalignant conditions, high risk was found for anal cancer (SIR 26.9 [95% CI 8.7-83.4]), vaginal/vulvar cancer (SIR 9.1 [95% CI 2.3-36.5]), epithelial dysplasia/carcinoma in situ of the uterine cervix (SIR 1.8 [95% CI 1.2-2.7]), and nonmelanoma skin cancer (SIR 2.0 [95% CI 1.2-3.6]). Increased SIRs were also found for other potentially virus-induced cancer types (liver cancer SIR 9.9 [95% CI 2.5-39.8], bladder cancer SIR 3.6 [95% CI 1.4-9.7], and non-Hodgkin's lymphoma SIR 5.0 [95% CI 1.9-13.3]).

CONCLUSION

The patients in this SLE cohort experienced an increased risk of HPV-associated tumors and other potentially virus-induced cancers during long-term followup. Our findings call for clinical alertness to oncogenic virus infections in SLE patients.

HIV infection status, immunodeficiency, and the incidence of non-melanoma skin cancer

Background The incidence of non-melanoma skin cancers (NMSCs), including basal cell (BCC) or squamous cell carcinoma (SCC), is not well documented among HIV-positive (HIV(+)) individuals. Methods We identified 6560 HIV(+) and 36 821 HIV-negative (HIV(-)) non-Hispanic white adults who were enrolled and followed up in Kaiser Permanente Northern California from 1996 to 2008. The first biopsy-proven NMSCs diagnosed during follow-up were identified from pathology records. Poisson models estimated rate ratios that compared HIV(+) (overall and stratified by recent CD4 T-cell counts and serum HIV RNA levels) with HIV(-) subjects and were adjusted for age, sex, smoking history, obesity diagnosis history, and census-based household income. Sensitivity analyses were adjusted for outpatient visits (ie, a proxy for screening). All statistical tests were two-sided. Results The NMSC incidence rate was 1426 and 766 per 100 000 person-years for HIV(+) and HIV(-) individuals, respectively, which corresponds with an adjusted rate ratio of 2.1 (95% confidence interval [CI] = 1.9 to 2.3). Similarly, the adjusted rate ratio for HIV(+) vs HIV(-) subjects was 2.6 (95% CI = 2.1 to 3.2) for SCCs, and it was 2.1 (95% CI = 1.8 to 2.3) for BCCs. There was a statistically significant trend of higher rate ratios with lower recent CD4 counts among HIV(+) subjects compared with HIV(-) subjects for SCCs (P trend < .001). Adjustment for number of outpatient visits did not affect the results. Conclusion HIV(+) subjects had a twofold higher incidence rate of NMSCs compared with HIV(-) subjects. SCCs but not BCCs were associated with immunodeficiency.

Incidence, risk factors, and preventative management of skin cancers in organ transplant recipients: a review of single- and multicenter retrospective studies from 2006 to 2010

BACKGROUND

Organ transplant recipients (OTRs) taking immunosuppressants are at high risk of skin cancer, which is the most common malignant condition in OTRs, so dermatologic surveillance is important for OTRs.

OBJECTIVES

To characterize the most common skin cancers arising from chronic immunosuppression in OTRs.

METHODS

A PubMed search for retrospective single- and multicenter studies reporting skin cancer incidence from 2006 to 2010 was undertaken. Data regarding each study's immunosuppressive regimen, affected skin cancer cohort, and associated risk factors were extracted.

RESULTS

Thirty-six articles that met our inclusion criteria reported incidences of nonmelanoma skin cancer (NMSC), Kaposi's sarcoma, melanoma, and Merkel cell carcinoma. NMSC was the most commonly reported cancer of all skin cancers after transplantation. Common risk factors were sex, age, sunlight exposure, and immunosuppressive agent-related (duration, type).

CONCLUSION

Sun education programs and frequent screenings in organ transplant clinics have provided the best preventative strategies after transplantation, although the characteristics of the immunosuppressive regimen also play an important role. Thus, the adjuvant strategy of modifying immunosuppression may be effective when confronting severe transplant-associated skin cancer. Although the decision-making process for curbing levels of immunosuppression is difficult, further long-term, randomized controlled studies should assess the effect of using less immunosuppressant medication while preserving graft function.

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

BACKGROUND

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

OBJECTIVE

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

METHODS

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

RESULTS

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

CONCLUSION

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

Multiple forms of DNA damage caused by UVA photoactivation of DNA 6-thioguanine

Thiopurines are prescribed frequently as medication for cancer and for inflammatory disorders. One of them, azathioprine, has been the immunosuppressant of choice for organ transplant recipients for many years. Thiopurine use is associated with elevated sun sensitivity and skin cancer risk. Skin sensitization is selective for UVA. 6-TG integrates into DNA and unlike the canonical DNA bases, it is a strong UVA chromophore with an absorbance maximum at 342 nm. DNA 6-TG is a photosensitizer and a source of reactive oxygen species. Reactive oxygen that is generated from the photochemical activation of DNA 6-TG causes extensive damage to DNA and proteins. This damage is mutagenic and extremely toxic to cultured human cells. Here we describe some of the lesions that are known to be generated from UVA irradiation of DNA 6-TG. We discuss how this photochemical damage might contribute to the toxic effect of thiopurine/UVA treatment on cultured cells and to the high risk of skin cancer in thiopurine-treated patients.

Skin cancer in solid organ transplant recipients: advances in therapy and management: part I. Epidemiology of skin cancer in solid organ transplant recipients

Skin cancer is the most frequent malignancy in organ transplant recipients, 95% of which are nonmelanoma skin cancer, especially squamous cell and basal cell carcinomas. This paper also discusses the incidence of other tumors (eg, melanoma, Merkel cell carcinoma, and Kaposi sarcoma) that are also increased in organ transplant patients compared to the general population. Part I of this two-part series describes the latest data concerning the epidemiologic and pathogenic aspects of nonmelanoma skin cancer development in solid organ transplant recipients. This review also highlights the concept of "field cancerization," represented by extensive areas of actinic damage and epidermal dysplasia, which accounts for increased risk of aggressive skin cancer development in susceptible patients.

High throughput sequencing reveals diversity of Human Papillomaviruses in cutaneous lesions

There are at least 120 completely characterized human papillomavirus (HPV) types and putative new types are continuously found. Both squamous cell carcinoma of the skin (SCC) and other skin lesions commonly contain multiple cutaneous HPV types. The objective of this study was to achieve an improved resolution of the diversity of HPV types in lesions such as SCCs, actinic keratoses (AKs) and keratoacanthomas (KAs). Fresh frozen biopsies from 37 SCC lesions, 36 AK lesions and 92 KA lesions and swab samples from the top of the lesion from 86 SCCs and 92 AKs were amplified using the general HPV primers FAP and mixed to three pools followed by high throughput sequencing. We obtained 2196 reads with homology to HPV. In the pool of SCC/AK biopsies 48 different HPV types were found. Eighty-three types were found in the pool of SCC/AK swab samples and 64 types in the KA biopsies, respectively. For 9 novel putative HPV types most of the amplimer sequence was obtained, whereas for an additional 35 novel putative HPV types only partial amplimer sequences were obtained. Most of the novel putative types belonged to the genus Gamma. In conclusion, high throughput sequencing was an effective means to identify both known and previously unknown HPV types in putatively HPV-associated lesions and has revealed an extended diversity of HPV types.

Sorafenib-induced premalignant and malignant skin lesions

PURPOSE

To review characteristics of patients who develop premalignant and malignant skin lesions while on sorafenib therapy and discuss implications for subsequent treatment of their primary malignancies.

BACKGROUND

Sorafenib is a newly developed multitargeted protein kinase inhibitor reported to induce a variety of adverse cutaneous effects, rarely including actinic keratoses, keratocanthomas, and squamous cell carcinomas (SCCs).

METHODS

Published reports of individuals who have developed cutaneous lesions demonstrating atypia of the epidermis are reviewed. In addition, a 77-year-old man who developed not only an SCC but also verrucas within one month of taking sorafenib monotherapy for metastatic adenocarcinoma of the lung is described.

RESULTS

Cutaneous lesions develop most commonly in Caucasian men older than 40 years without previous histories of skin cancer, within two weeks to three years of starting sorafenib therapy. Currently there is no definitive explanation for the relationship between sorafenib and cutaneous neoplasms. Management typically involves treatment of skin lesions with cryotherapy or excision with at least a brief discontinuation of sorafenib. In patients whose primary malignancies were responding well, sorafenib therapy was continued with close follow-up.

CONCLUSIONS

The possibility of rapidly developing actinic keratoses, keratocanthomas, verrucas, and SCC during treatment with sorafenib, warrants close dermatologic follow-up and a lower threshold for biopsy and treatment of suspicious cutaneous lesions. Development of a sorafenib-induced SCC is not an absolute contraindication for continued use of sorafenib therapy; however, the drug should be briefly discontinued until lesions are treated.

Determination of the relationship between Basal cell carcinoma and human papilloma virus, based on immunohistochemistry staining method

Background:

Basal cell carcinoma (BCC) is the most common skin cancer among Caucasians, and in most cases, occurs in the sun-exposed areas. In recent years, in addition to many other etiologies such as exposure to UV radiation, and occasionally xeroderma pigmentosa, burns, tattoos, and pox scars, human papillomavirus (HPV) is also considered to have an etiologic role. Different studies were conducted with varied results in this regard.

Aims:

We evaluate this plausible relationship between HPV and BCC by means of immunohistochemistry (IHC) staining method.

Methods:

This is an analytic cross-sectional study in which 160 samples were selected randomly consisting of 80 BCC lesions and 80 safe margins. Sampling was done among paraffin-embedded blocks in pathology ward of Kashani and Alzahra hospitals, Isfahan-Iran, from 2004-2007. A section of each block was IHC stained for HPV immunoreactivity (DAKO, Denmark). This was followed by microscopic evaluation in terms of being positive or negative.

Results:

Fifty seven point five percent of the samples belonged to men and the others to women. In 10%, HPV marker was positive, both in lesion and margin. In 83.8% neither the lesions nor the margins were immunoreactive for HPV. Only in 5 cases (6.3%) the lesion was positive and the margin was negative for this marker. There was no case of immunoreactivity for HPV marker in margins, while it was negative in lesions. Our study results followed by McNemar analysis did not show a significant relationship between BCC incidence and HPV existence. This was consistent in both genders (P > 0.05, power > 90%).

Conclusion:

In this study we did not find a significant relationship between BCC and HPV, but based on review of articles it appears that large multicentric studies are to be conducted in this regard.