Presence of high-risk mucosal human papillomavirus genotypes in primary melanoma and in acquired dysplastic melanocytic naevi

Detection of human papillomavirus (HPV) in malignant melanoma

The most common type of melanoma is cutaneous melanoma (CM). The predominant mutational signature is that of ultraviolet radiation (UVR) exposure. The Cancer Genome Atlas (TCGA) molecular classification includes four major subtypes of CM based on common genetic alterations involving the following genes: BRAF, NRAS, and NF1, with a small fraction being "triple" wild-type. The two main signaling pathway abnormalities in CM are the mitogen-activated protein kinase (MAPK) pathway and the phosphoinositol-3-kinase (PI3K) pathway. Other less common types include mucosal melanomas (MM) and uveal melanoma (UM), which have a significantly different genomic landscape. Although few studies reported rare cases with HPV-positive (HPV+) melanoma, the clinicopathological and molecular characteristic of this entity has not been well-described. Among the 2084 melanoma cases queried at our institution, we identified seven patients diagnosed with HPV+ melanoma (prevalence 0.03 %), including five instances of CM and two of MM. The majority of cases were positive for HPV16 (n = 6). Most of the patients were elderly and with advanced disease (n = 6), although this finding may be attributed to the relative frequency of our institution testing advanced-stage tumors. Histologically, most cases showed high degree of pleomorphism and high mitotic count (5 or more mitoses/mm2) (n = 6). UVR signature was present in the CM, but not in the MM cases. Alterations in either MAPK and/or PI3K pathways were detected in the majority of cases (n = 6). The most common genetic abnormalities detected in this study occurred in the TERT promoter (TERTp) (n = 5), a finding that has been reported to be associated with aggressive disease. Our data shows that while HPV+ melanoma is rare, identifying this disease entity could help guide therapy given the demonstrated genomic alterations.

Molecular mechanisms of human papilloma virus related skin cancers: A review

The human papillomavirus (HPV) belongs to the Papillomaviridae family of viruses which includes small, double-stranded DNA viral agents. Approximately 90% of HPV infections occur asymptomatically and resolve spontaneously. However, infection with high-risk viral strains can lead to the development of preneoplastic lesions, with an increased propensity to become cancerous. The location of these malignancies includes the oral cavity, cervix, vagina, anus, and vulva, among others. The role of HPV in carcinogenesis has already been demonstrated for the aforementioned neoplasia. However, regarding skin malignancies, the mechanisms that pinpoint the role played by HPV in their initiation and progression still elude our sight. Until now, the only fully understood mechanism of viral cutaneous oncogenesis is that of human herpes virus 8 infection in Kaposi sarcoma. In the case of HPV infection, however, most data focus on the role that beta strains exhibit in the oncogenesis of cutaneous squamous cell carcinoma (cSCC), along with ultraviolet radiation (UVR) and other environmental or genetic factors. However, recent epidemiological investigations have highlighted that HPV could also trigger the onset of other non-melanocytic, for example, basal cell carcinoma (BCC), and/or melanocytic skin cancers, for example, melanoma. Herein, we provide an overview of the role played by HPV in benign and malignant skin lesions with a particular focus on the main epidemiological, pathophysiological, and molecular aspects delineating the involvement of HPV in skin cancers.

Mucosal Melanoma Clinical Management and Prognostic Implications: A Retrospective Cohort Study

Mucosal melanoma (MM) is an uncommon melanoma subtype affecting mucosal surfaces of the head and neck, anorectal region, and vulvovaginal area. We aimed to present our experience at a tertiary-level hospital regarding MM diagnosis, management, monitoring of progression, mutations, and outcome predictors. We performed a registry-based cohort study including MM cases diagnosed from 2012 to 2022 and retrospectively characterized somatic mutations on BRAF, NRAS and c-KIT. We employed Kaplan-Meier curves, log-rank tests, and Cox regression analysis to explore prognostic factors and survival outcomes in a cohort of 35 patients, mainly women (63%) with a median age of 70 years. Predominantly, MM occurred in the vulvovaginal region (48.6%). At diagnosis, 28.6% had lymph node involvement, and 31.4% also had distant metastasis. Mutations in BRAF and c-KIT were identified in 3/35 (9%) and 2/6 patients (33%), respectively. Surgery was performed in 71.4% of patients, and most received systemic treatment (65.7%). Lower disease stage, thinner Breslow depth, and surgical resection were associated with improved overall survival. Notably, age, sex, radiotherapy, and BRAF mutant status did not affect survival. Standard management typically involves immunotherapy. Cases with BRAF or c-KIT mutations may be considered for targeted therapies. Unfortunately, MM prognosis remains unfavorable, with a less than 50% survival rate at 2 years.

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

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

Microbiota, Oxidative Stress, and Skin Cancer: An Unexpected Triangle

Mounting evidence indicates that the microbiota, the unique combination of micro-organisms residing in a specific environment, plays an essential role in the development of a wide range of human diseases, including skin cancer. Moreover, a persistent imbalance of microbial community, named dysbiosis, can also be associated with oxidative stress, a well-known emerging force involved in the pathogenesis of several human diseases, including cutaneous malignancies. Although their interplay has been somewhat suggested, the connection between microbiota, oxidative stress, and skin cancer is a largely unexplored field. In the present review, we discuss the current knowledge on these topics, suggesting potential therapeutic strategies.

Oncoviruses and melanomas: A retrospective study and literature review

The role of human oncoviruses in melanoma has been poorly investigated. The aim of this study was to investigate the association between oncoviruses and melanomas searching for human papillomavirus (HPV), Epstein Barr virus (EBV), and human herpesvirus 8DNA in melanoma specimens. Formalin-fixed and paraffin-embedded tissue specimens of cutaneous, mucosal, and ocular melanomas (OM) were selected from the Pathology Departments of the Galliera Hospital (Genoa) and the University Hospitals of Turin and Cagliari. Cutaneous and mucosal nevi have been collected as controls. The oncoviruses search has been performed with different polymerase chain reaction reagent kits. Fifty-four melanomas (25 mucosal, 12 ocular, and 17 cutaneous) and 26 nevi (15 cutaneous and 11 mucosal) specimens were selected. The detection rate for one of the investigated oncoviruses was 17% in mucosal, 20% in ocular, and 0% in cutaneous melanomas (CMs). Despite the differences between groups seeming remarkable, there was no statistical significance (p > 0.5). Our data do not support a primary role of oncoviruses in melanoma carcinogenesis; however, the finding of HPV and EBV DNA in a considerable fraction of mucosal and OMs suggests that these viruses may act as cofactors in the development of extra-CMs.

Mucosal Melanoma: A Review Emphasizing the Molecular Landscape and Implications for Diagnosis and Management

Mucosal melanomas are rare, often aggressive tumors that can arise at any mucosal site but most frequently occur in the head and neck, vulvovaginal, and anorectal regions. They have distinct biological, clinical, and histopathologic features, which have important management implications. Recent whole-genome sequencing studies have led to a greater understanding of the molecular landscape of mucosal melanomas and uncovered oncogenic drivers that could potentially be susceptible to therapeutic manipulation. The authors provide a brief overview of epidemiologic, clinical, and histopathologic features of mucosal melanoma, with particular emphasis on recent advances in understanding, which have arisen from analyzing their molecular landscape.

The Impact of Human Papillomavirus Infection on Skin Cancer: A Population-Based Cohort Study

BACKGROUND

This study investigated the correlation between a history of human papillomavirus (HPV) infection and skin cancer risk.

MATERIALS AND METHODS

The study cohort comprised 26,919 patients with newly diagnosed HPV infection between 2000 and 2012; with the use of computer-generated numbers, patients without previous HPV infection were randomly selected as the comparison cohort. The patients in the HPV infection cohort were matched to comparison individuals at a 1:4 ratio by demographic characteristics and comorbidities. All study individuals were followed up until they developed skin cancer, withdrew from the National Health Insurance program, were lost to follow-up, or until the end of 2013. The primary outcome was subsequent skin cancer development. Cox proportional hazards regression analysis was used to analyze the risk of skin cancer with hazard ratios (HRs) and 95% confidence intervals (CIs) between the HPV and control cohort.

RESULTS

The adjusted HR of skin cancer for patients with HPV relative to controls was 2.45 after adjusting sex, age and comorbidities. (95% CI, 1.44-4.18, p < .01). The subgroup analysis indicated that a patient with HPV infection had a significantly greater risk of skin cancer if they were aged >40 years. Notably, a risk of skin cancer was found in the group diagnosed with HPV within the first 5 years after the index date (adjusted HR, 3.12; with 95% CI, 1.58-5.54). Sensitivity analysis by propensity score, matching with balanced sex, age, and comorbidities, showed consistent results.

CONCLUSION

A history of HPV infection is associated with the development of subsequent skin cancer in Taiwanese subjects, and the risk wanes 5 years later.

IMPLICATIONS FOR PRACTICE

In this Taiwan nationwide cohort study, there was a 2.45-fold increased risk of developing new-onset skin cancers for patients with incident human papillomavirus (HPV) infection, compared with the matched controls. Furthermore, the risk was noticeably significant among patients aged >40 years. A prominent risk of skin cancers was found in the group diagnosed with HPV within the first 5 years after the index date in this study. The results of this analysis may raise consensus on the effect of HPV infection on the risk of skin cancers. Clinicians are encouraged to implement prudently on the differential diagnosis of skin cancers and HPV prevention and treatment, especially in older patients.

Prevalence of Equus caballus Papillomavirus Type-2 Infection and Seropositivity in Asymptomatic Western Canadian Horses

Equus caballus papillomavirus type 2 (EcPV-2) has been recognized as a potential cause of a subset of genital squamous cell carcinomas (SCCs) in horses. In the current study, we measured EcPV-2 seropositivity in 50 healthy horses from Western Canada, and these were compared to a herd of horses with known EcPV-2 exposure. Second, the presence of EcPV-2 DNA was measured using EcPV-2-specific PCR (polymerase chain reaction), performed on a variety of tissues collected at necropsy from 70 horses that lacked any history, gross, or histologic evidence of neoplasia or papillomavirus-associated disease. EcPV-2-specific RNA in situ hybridization (R-ISH) was performed on PCR-positive samples to identify the specific tissues infected. The prevalence of asymptomatic infection with EcPV-2 in Western Canadian horses was 20/70 (29%). Exposure to EcPV-2 as measured by seropositivity was 18/50 (36%). EcPV-2 positivity by anatomic location, as measured by R-ISH, was as follows: penis 10/29 (35%), vulva 5/34 (15%), eyelid 8/68 (12%), oral mucosa 7/65 (11%), skin from muzzle 7/68 (10%), and retropharyngeal lymph node 2/64 (3%). The youngest horses with EcPV-2 infection, based on PCR, were fetuses, suggesting for the first time that vertical transmission of EcPV-2 occurs in horses. The current study observed an increased prevalence of EcPV-2 as compared to previous studies. We suggest that this difference is due to our use of biopsies in place of superficial swabs. We propose that EcPV-2 infection in asymptomatic horses is more common than previously reported and that the virus' role in equine genital SCCs may be more complex than originally thought.

Metabolic Traits in Cutaneous Melanoma

Tumor microenvironment is a network of complex cellular and molecular systems where cells will gain specific phenotypes and specific functions that would drive tumorigenesis. In skin cancers, tumor microenvironment is characterized by tumor infiltrating immune cells that sustain immune suppression, mainly lymphocytes. Melanoma cellular heterogeneity can be described on genetic, proteomic, transcriptomic and metabolomic levels. Melanoma cells display a metabolic reprogramming triggered by both genetic alterations and adaptation to a microenvironment that lacks nutrients and oxygen supply. Tumor cells present clear metabolic adaptations and identifying deregulated glycolysis pathway could offer new therapy targets. Moreover, the immune cells (T lymphocytes, macrophages, NK cells, neutrophils and so on) that infiltrate melanoma tumors have metabolic particularities that, upon interaction within tumor microenvironment, would favor tumorigenesis. Analyzing both tumor cell metabolism and the metabolic outline of immune cells can offer innovative insights in new therapy targets and cancer therapeutical approaches. In addition to already approved immune- and targeted therapy in melanoma, approaching metabolic check-points could improve therapy efficacy and hinder resistance to therapy.

Cutaneous malignant melanoma incidences analyzed worldwide by sex, age, and skin type over personal Ultraviolet-B dose shows no role for sunburn but implies one for Vitamin D3

Because the incidence of cutaneous malignant melanoma (CMM) was reported to increase with increasing terrestrial UVR (290-400 nm) doses in the US back in 1975 and a recent publication showed no association exists with UVR exposure at all, we set out to fully elucidate the role of UVR in CMM. To achieve this goal, we analyzed the CMM incidences over latitude and estimated the average personal UVR dose in the US and numerous countries (> 50) on 5 continents around the world. Using data from the International Agency for Research on Cancer in 2005, we performed worldwide analysis of CMM over UVR dose by sex, age group (0-14, 15-29, 30-49, 50-69, 70-85+) and Fitzpatrick skin types I-VI. Surprisingly, increasing UVR doses, which represent erythemally-weighted doses comprised primarily of UVB (290-315 nm) radiation, did not significantly correlate with increasing CMM incidence for people with any skin type anywhere in the world. Paradoxically, we found significant correlations between increasing CMM and decreasing UVB dose in Europeans with skin types I-IV. Both Europeans and Americans in some age groups have significant increasing CMM incidences with decreasing UVB dose, which shows UVB is not the main driver in CMM and suggests a possible role for lower cutaneous vitamin D₃ levels and UVA (315-400 nm) radiation. CMM may be initiated or promoted by UVA radiation because people are exposed to it indoors through windows and outdoors through some sunscreen formulations. Thus, our findings may explain why some broad-spectrum sunscreen formulations do not protect against getting CMM.

Worldwide cutaneous malignant melanoma incidences analyzed by sex, age, and skin type over time (1955-2007): Is HPV infection of androgenic hair follicular melanocytes a risk factor for developing melanoma exclusively in people of European-ancestry?

The cutaneous malignant melanoma (CMM) incidence has been increasing in an exponential manner in certain populations around the world for over 7 decades. To help illuminate the etiology, we performed worldwide temporal (1955–2007) CMM incidence analysis by sex, age (0–14, 15–29, 30–49, 50–69, 70–85+), and skin type on 6 continents using data from the International Agency for Research on Cancer. We observe an exponential increase in the CMM incidence over time and an increase of about 2 orders of magnitude between age groups 0–14 and 15–29 exclusively in European-ancestry populations around the world independent of skin type (I–III or III–IV). Other populations like the Chinese (III-IV) had much lower CMM incidences that either remained stable or temporally decreased but did not display a dramatic increase between the youngest age groups. The dramatic increase in the incidence between the youngest age groups found only in European-ancestry populations suggests one of the most important risk factors for CMM may be developing androgenic hair, the occurrence of which appears to correlate with the distribution of CMM over male and female body sites. Besides that potential new risk factor, the increasing CMM incidence with increasing age, known not to be from cumulative UV doses, may be associated with age-related changes to skin, i.e., thinning epidermis causing lower vitamin D₃ levels, and hair, i.e., whitening from higher reactive oxygen species. The temporal exponential increasing CMM incidence in European-ancestry populations may be due to Human Papilloma Virus infection of follicular hair melanocytes, found in CMM biopsies.

Exponentially increasing incidences of cutaneous malignant melanoma in Europe correlate with low personal annual UV doses and suggests 2 major risk factors

For several decades the incidence of cutaneous malignant melanoma (CMM) steadily increased in fair-skinned, indoor-working people around the world. Scientists think poor tanning ability resulting in sunburns initiate CMM, but they do not understand why the incidence continues to increase despite the increased use of sunscreens and formulations offering more protection. This paradox, along with lower incidences of CMM in outdoor workers, although they have significantly higher annual UV doses than indoor workers have, perplexes scientists. We found a temporal exponential increase in the CMM incidence indicating second-order reaction kinetics revealing the existence of 2 major risk factors. From epidemiology studies, we know one major risk factor for getting CMM is poor tanning ability and we now propose the other major risk factor may be the Human Papilloma Virus (HPV) because clinicians find β HPVs in over half the biopsies. Moreover, we uncovered yet another paradox; the increasing CMM incidences significantly correlate with decreasing personal annual UV dose, a proxy for low vitamin D3 levels. We also discovered the incidence of CMM significantly increased with decreasing personal annual UV dose from 1960, when it was almost insignificant, to 2000. UV and other DNA-damaging agents can activate viruses, and UV-induced cytokines can hide HPV from immune surveillance, which may explain why CMM also occurs in anatomical locations where the sun does not shine. Thus, we propose the 2 major risk factors for getting CMM are intermittent UV exposures that result in low cutaneous levels of vitamin D3 and possibly viral infection.

Human papillomavirus and the incidence of nonmelanoma and melanoma skin cancer using cervical conization as a surrogate marker: a nationwide population-based Danish cohort study

PURPOSE

Human papillomavirus' (HPV's) role in skin cancer is controversial. To examine whether an individual is prone to develop a chronic oncogenic infection, we conducted a nationwide population-based cohort study of the risk of skin cancer after another HPV-related neoplasia-that is, cervical high-grade dysplasia or carcinoma-using cervical conization as a surrogate marker.

METHODS

Using Danish registries, we identified all women who underwent conization from 1978 to 2011 (n = 87,164) and followed them until first-time skin cancer diagnosis, death, emigration, or 31 December 2011, whichever came first. We calculated standardized incidence ratios (SIRs) and 95% confidence intervals (CIs) for basal cell carcinoma (BCC), squamous cell carcinoma (SCC), and malignant melanoma (MM) according to national incidence rates.

RESULTS

The 1-year absolute risks were 0.0012%, 0.045%, and 0.029% for SCC, BCC, and MM, respectively. Conization was clearly associated with increased incidence of SCC (SIR = 1.37; 95% CI: 1.13-1.65), but not MM (SIR = 1.00; 95% CI: 0.91-1.11). BCC risk was slightly increased (SIR = 1.08; 95% CI: 1.02-1.13).

CONCLUSIONS

The association between conization and cutaneous SCC provides evidence for conization as a marker of underlying general susceptibility to oncogenic HPV.

HPV-associated diseases

Nearly 200 distinct human papilloma viruses (HPVs) have now been recognized, and each is associated with a specific set of clinical lesions. They are associated with a spectrum of diseases, from benign verrucae vulgares and condylomata acuminata to the malignancies of the cervix, vulva, anus, and penis. Disease associated with HPV can be divided into skin and mucosal lesion of the genital and extragenital regions. The relationship between HPV and nonmelanoma skin cancer (NMSC) is important clinically, because NMSC is the most common form of malignancy among fair-skinned populations. HPVs have also been detected in skin tags, lichen sclerosus, seborrheic keratoses, actinic keratoses, epidermal cysts, psoriatic plaques, and plucked hairs, but cutaneous HPV can be found on healthy skin.

Clustering of cutaneous melanoma in health care workers of a dermatological day hospital unit

BACKGROUND

The incidence of cutaneous melanoma is increasing but in most countries is still below 20/100,000 per year. Despite such a low frequency of occurrence, recently the authors have had notice of several new melanoma cases among colleagues. We carried out a survey of melanoma occurrence among the personnel, and their close relatives, of a dermatological clinic. The self-reported figures were compared with data from cancer registries.

OBSERVATIONS

Thirty-eight doctors and nurses were surveyed. Three responders reported having had a diagnosis of melanoma (7.9%, 95% CI 1.7-21.4%). The respondents reported having 617 'relatives who are alive today and would have come to them if they had a melanoma': 12 had known diagnoses of melanoma (1.9%, 95% CI 1.0-3.4%). The relative risks were 26.3 (95% CI 8.9-78.0) and 4.1 (95% CI 1.2-13.8) for doctors and nurses compared to the general population and to their relatives, respectively, and 6.5 (95% CI 3.7-11.4) for relatives compared to the general population.

CONCLUSIONS

Two nonmutually exclusive hypotheses may be formulated to explain these findings: (a) most cutaneous melanomas regress spontaneously; (b) an infectious agent is involved in the causal pathway of cutaneous melanoma. Further studies may be warranted to confirm our observations and test such hypotheses.

BD ProEx C immunostaining in extramammary Paget's disease and perineal melanoma

The differential diagnosis of perineal biopsies can include squamous intraepithelial lesions, extramammary Paget's disease, and melanoma. Less frequently two of these lesions coexist. BD ProEx C is a recently developed immunoassay that targets expression of two genes shown to be associated with cervical cancer. Immunostaining for ProEx C has been validated in cervical cytology and positive staining has also been shown to be strongly associated with human papilloma virus (HPV)-induced cervical and anal intraepithelial neoplasia in biopsies. We observed positive staining for ProEx C in Paget cells in all of 26 cases of Paget's disease irrespective of tissue site (extramammary, mammary) and in melanoma cells in all of 12 cases of primary perineal melanoma with immunostaining in >50% of malignant cells in 73% of Paget disease cases and 43% of perineal melanoma cases. Positive staining was heterogeneous and exclusively nuclear in all cases. In situ hybridization was negative for low-risk and high-risk HPV subtypes in all Paget and melanoma cases that were tested. Currently neither of these lesions is known to be HPV related although according to the literature the possibility of a role for HPV in melanoma is still unsettled. Relevant literature is reviewed.

Case report of primary rectal melanoma and review of the etiology of melanoma

BACKGROUND

Primary rectal melanoma is a very rare and aggressive malignancy. It is defined as melanoma arising in the rectal mucosa, more than 4 cm from the anal verge.

OBJECTIVE

A case of primary rectal melanoma is reported, and the theories of the etiology of melanoma are reviewed.

METHODS AND RESULTS

This article reports a case of a 75-year-old woman who presented with lower gastrointestinal bleeding and abdominal discomfort. A polyp was removed from the low-lying rectum during colonoscopy. After immunohistochemical staining and microscopic examination, it was diagnosed as melanoma.

CONCLUSION

In light of primary melanoma in sun-shielded regions such as the rectum, theories of causation other than sun exposure merit consideration. Factors such as genetics, immunosuppression, and virus infections, as well as ultraviolet radiation, may play a role in the etiology of melanoma.

Qualitative PCR-ELISA protocol for the detection and typing of viral genomes

PCR is an established technique providing rapid and highly productive amplification of specific DNA sequences. The demand for equally rapid, sensitive and objective methods to achieve detection of PCR products has led to the coupling of PCR with ELISA. PCR-ELISA involves direct incorporation of labeled nucleotides in amplicons during PCR-amplification, their hybridization to specific probes and hybrid capture-immunoassay in microtiter wells. PCR-ELISA is performed in 1 d and is very flexible, with the ability to process simultaneously up to 96 or 384 samples. This technique is potentially automatable and does not require expensive equipment, and thus can be fundamental in laboratories without access to a real-time PCR thermocycler. PCR-ELISA has mainly been used to detect infectious agents, including viruses, bacteria, protozoa and fungi. A PCR-ELISA protocol for the qualitative detection of papillomavirus genomes and simultaneous typing of different genotypes are detailed here as an example of the technique.

Assessment of the presence of mucosal human papillomaviruses in malignant melanomas using combined fluorescent in situ hybridization and chemiluminescent immunohistochemistry

BACKGROUND

The vast majority of studies aimed at detecting human papillomavirus (HPV) DNA in skin cancer have used sensitive polymerase chain reaction (PCR) methods but the PCR technique, despite its high sensitivity, is not suitable to ascertain whether (i) the presence of HPV can be related only to few cells harbouring the virus, (ii) the presence of HPV is due to a tumour surface contamination and (iii) the presence of HPV is localized in cancer cells, rather than in normal keratinocytes present in the tumour biopsy. In a recent work we have found mucosal high-risk (HR) HPV genotypes in primary melanoma by PCR.

OBJECTIVES

To localize mucosal HR-HPV nucleic acids and tumoural melanocytic marker in the same sections of primary melanoma samples in order to understand the relationship between HPVs and melanoma cells.

METHODS

We have developed a very sensitive method that combines an enzyme-amplified fluorescent in situ hybridization (ISH) for the detection of HPV nucleic acids (types 16 and 18) with a chemiluminescent immunohistochemistry (IHC) method for the detection of the tumoural melanocytic marker HMB-45 sequentially in the same section. Digital images of fluorescent ISH and chemiluminescent IHC were separately recorded, assigned different colours and merged using specific software for image analysis.

RESULTS

The combined fluorescent ISH and chemiluminescent IHC demonstrated a sharp colocalization (in the range 60-80%) of HPV nucleic acids and melanoma marker inside the same sections of melanoma biopsies, with a strong specificity and sensitivity.

CONCLUSIONS

The strong colocalization of mucosal HR-HPV nucleic acids and HMB-45 melanocytic marker emphasized that viral nucleic acids were specifically present in melanoma cells and supported a possible active role of HPV in malignant melanoma.

Prevalence of mucosal types of human papillomavirus in skin lesions in north part of Iran

Human papillomaviruses (HPVs) consist of more than 100 types and are known to be associated with numerous malignant tumors, including carcinomas of the mucosal and cutaneous epithelium. Non-melanoma skin cancer (NMSC) is the most frequently occurring malignancy worldwide in the Caucasian population. Some studies have shown that NMSC biopsy specimens harbor cutaneous as well as mucosal human papillomavirus, suggesting that mucosal types may play a role in development and progression of the tumor in skin. To investigate the presence of mucosal HPV types in skin lesions, we performed a retrospective study in which 288 paraffin embedded biopsies from benign and malignant skin lesions (NMSC) were collected. Using nested PCR with MY09/11 and GP5+/6+ primers mucosal HPVs were detected in 25.7% of malignant specimens, but just in 0.7% of benign lesions. Direct sequencing revealed HPV18 as the most frequent type, which was found in 75% of HPV-positive specimens. HPV16 and HPV56 were also detected, 22.3 and 2.7%, respectively. These findings suggest that, high-risk mucosal HPV types recently identified as significant risk factors for cervical cancer, may also represent a risk factor for non-melanoma skin cancer.

Epidermodysplasia Verruciformis and Cutaneous Human Papillomavirus DNA, but Not Genital Human Papillomavirus DNAs, Are Frequently Detected in Vulvar and Vaginal Melanoma

Vulvovaginal melanomas are rare and their etiology is unknown. Genital mucosal human papillomavirus (HPV) 16 has been identified in both cutaneous and mucosal melanoma, suggesting that it might play a role in the pathogenesis or progression of melanoma. In this study, we investigated the prevalence of HPV DNA by using a broad spectrum of degenerate and type-specific primers for genital-mucosal, epidermodysplasia verruciformis-associated (EV), and cutaneous HPV types in 6 vulvar and 3 vaginal melanomas. The patients were mostly postmenopausal women (8/9), had a mean age of 67 years (range, 44-85 years), and had mucosal lentiginous (7) or nodular (2) melanomas. In the adjacent skin/mucosa, mucosal melanosis was found in 5, lichen sclerosus or a lichenoid mucositis in 4, and blue nevi in 2 women. With nested polymerase chain reaction techniques followed by direct sequencing, HPV DNA was identified in 6 of 9 (67%) melanomas; these were either cutaneous (HPV 3) (4/9) or epidermodysplasia verruciformis-associated types (HPV 38, Z95969, AJ00151) (4/9). Epidermodysplasia verruciformis-associated HPV (type 15) was found solely in 1/10 (10%) normal vulvar controls. Genital-mucosal HPV types were not detected either by degenerate nested polymerase chain reaction or type-specific probes for HPV 16. We propose that the above findings are not coincidental but may represent a molecular record of HPV involvement in pathogenesis or progression of melanoma, which is consistent with the strong but poorly defined association of cutaneous HPV types with nonmelanoma skin cancers. The theory that HPV may act as a cofactor in melanoma development deserves further clinical and experimental investigations.