Human papillomavirus type 17 transcripts expressed in skin carcinoma tissue of a patient with epidermodysplasia verruciformis

Merkel cell polyomavirus and HPV-17 associated with cutaneous squamous cell carcinoma arising in a patient with melanoma treated with the BRAF inhibitor dabrafenib

IMPORTANCE

Approximately 10% to 25% of patients treated with BRAF inhibitors develop cutaneous squamous cell carcinoma (SCC), but the mechanism responsible has not yet been determined. We report what we believe to be the first case in which Merkel cell polyomavirus (MCPyV) and human papillomavirus subtype 17 (HPV-17) were associated with cutaneous SCC that developed during treatment with the BRAF inhibitor dabrafenib.

OBSERVATIONS

A 62-year-old woman with V600E BRAF -mutant metastatic melanoma enrolled in a phase 1 trial of dabrafenib, a selective inhibitor of V600-mutant BRAF kinase. During the first 6 weeks of treatment, the patient developed multiple skin lesions, including a 6-mm crusted papule on the left eyebrow, which was resected and, on pathology examination, revealed SCC. The DNA extracted from paraffin-embedded tissue was amplified by polymerase chain reaction for detection of MCPyV and epidermodysplasia verruciformis HPV (EV-HPV) types. Analysis of the cloned and sequenced polymerase chain reaction products revealed the presence of MCPyV and HPV-17 DNA. Other EV-HPV subtypes were not detected.

CONCLUSIONS AND RELEVANCE

To our knowledge, this is the first report demonstrating the coexistence of MCPyV and HPV-17 in cutaneous SCC. Because both viruses have oncogenic potential, their role in the development of BRAF inhibitor-related SCC merits further investigation.

Bead-based multiplex genotyping of 58 cutaneous human papillomavirus types

Cutaneous human papillomaviruses (HPVs) are a heterogeneous, nonmonophyletic assembly, comprising about 50 characterized types and at least 133 isolates putatively representing new types. Their natural history of infection and potential association with nonmelanoma skin cancer are not well understood. Several PCR systems have been developed that amplify a broad spectrum of cutaneous HPVs. However, amplicon genotyping by sequencing or reverse line blot assays are complex and not well suited for high-throughput analyses. We developed a novel multiplex cutaneous papillomavirus genotyping (McPG) assay for 38 defined and 20 putative cutaneous HPVs of the beta, gamma, mu, and nu genera. Viral DNA was amplified by the use of a modified single-tube nested "hanging-droplet" FAP PCR. The amplifiable papillomavirus (PV) spectrum was enlarged by the use of 9 outer and 13 inner primers. Biotinylated PCR products were hybridized to type-specific oligonucleotide probes coupled to fluorescence-labeled polystyrene beads and analyzed using Luminex technology. Analytical sensitivity was analyzed for 38 defined HPVs and was ≤100 genome copies for all types. Integrated β-globin primers allow for simultaneous DNA quality control. McPG is characterized by high reproducibility (κ= 0.84, 95% confidence interval = 0.79 to 0.88), good concordance with the original nested FAP PCR, followed by sequencing (70.2% complete or partial agreement) when 322 skin biopsy DNA samples were analyzed, and improved ability to detect multiple infections (on average 2.5 HPV types per HPV-positive sample compared to 1.7 HPV types with nested FAP-PCR). In conclusion, McPG is a powerful tool for genotyping multiple cutaneous HPVs in a high-throughput format and is thus suitable for large-scale epidemiological studies.

Seroreactivity of 38 human papillomavirus types in epidermodysplasia verruciformis patients, relatives, and controls

Epidermodysplasia verruciformis (EV) is a rare recessive genodermatosis characterized by high susceptibility to infections with human papillomaviruses (HPVs) of genus beta. Knowledge about seroreactivity against HPV in these patients and their first-degree relatives is scarce. Using multiplex serology, we analyzed antibodies to 38 HPV types from five genera in 32 EV patients, 22 first-degree relatives, and 64 and 44 age- and sex-matched, non-related, healthy controls, respectively. EV patients showed higher seroprevalences than non-related controls with statistically significant odds ratios (ORs) for 5 of 10 investigated alpha (OR range 6.9-21.3), all 16 beta (OR range 12.3-61.3), 3 of 9 gamma (OR range 6.4-11.7), and 1 of 2 micro HPVs (OR 5.8). In comparison to their relatives, antibodies in EV patients were significantly more prevalent for 4 of 16 beta HPVs (OR range 12.5-25.6), but for none of the other genera. A significantly increased seroprevalence in relatives compared with their controls was only seen for HPV 5 (OR 22.1). The considerably elevated HPV seroprevalence in EV patients, especially for beta papillomaviruses (PVs), reflects the high viral load described for these individuals. Whether the observed differences between relatives and healthy controls depend on heterozygosity for EV-associated alleles requires further investigation.

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

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

Epidermodysplasia verruciformis

Epidermodysplasia verruciformis is an uncommon cutaneous entity characterized by persistent human papillomavirus infection. A defect in cell-mediated immunity is the suggested causative factor. Numerous specific human papillomavirus types have been detected in this disease. Multiple nonmelanoma skin cancers are commonly seen in such patients; thus, early diagnosis is beneficial.

Human papillomavirus: a review

Human papillomavirus infection remains a great source of morbidity and mortality. Progress in understanding the structure of HPV and its pathogenesis has led to a wide variety of possible new treatment modalities to combat HPV-related disease. Most HPV infections (whether high risk or low risk) resolve without any medical intervention. Persistent or progressive disease, however, remains difficult to treat. Although currently available therapies have proved efficacious and tolerable in the treatment of nongenital and genital warts, no single therapy is uniformly effective in eradicating persistent HPV infection. Cytodestructive methods, such as cryotherapy, remain the primary treatment modality for nongenital warts. Immune response modifiers, such as imiquimod, currently show the greatest promise in treating HPV-induced anogenital lesions, both with respect to complete response and in preventing recurrence. Human papillomavirus infection is one of the most common sexually transmitted diseases in the world, and cervical cancer still causes significant morbidity and mortality. Pap smear tests have greatly reduced the incidence and mortality of cervical cancer in developed countries. Additional research will focus on primary and secondary prevention strategies. Vaccines against high-risk HPV types are promising modalities currently under investigation to prevent HPV infections and possibly to treat them.

Clinical, histopathologic, and molecular aspects of cutaneous human papillomavirus infections

Human papillomaviruses comprise a large family of double stranded DNA viruses that are the etiologic agents of benign warts and anogenital cancers. At least 82 different human papillomavirus types have been identified and many remain yet uncharacterized. The development of new molecular techniques in recent years has led to an increased understanding of human papillomaviruses and their roles in carcinogenesis. Several clinicopathologic entities arising from human papillomavirus infection encountered by the dermatologist are the subject of the article. The epidemiology, molecular biology, clinical presentation, histologic findings, and treatment of each disorder, where applicable, is discussed.

Epidermodysplasia verruciformis as a model of human papillomavirus-induced genetic cancers: the role of local immunosurveillance

Epidermodysplasia verruciformis (EV) presents a genetically determined, unusual susceptibility to infection with EV-specific human papillomaviruses (HPVs) related to abrogation of immunosurveillance exclusively against these viruses. The cutaneous viral carcinogenesis depends upon potentially oncogenic HPVs, the cocarcinogenic effect of ultraviolet irradiation, and genetic host factors, presumably a defect of anti-oncogenes or alleles of major histocompatibility complex and tumor necrosis factor locus involved in antigen presentation.

Genetic heterogeneity among human papillomaviruses (HPV) associated with epidermodysplasia verruciformis: evidence for multiple allelic forms of HPV5 and HPV8 E6 genes

In order to get some insight into modifications of human papillomavirus (HPV) genomes which could play a role in tumor progression in epidermodysplasia verruciformis (EV), we studied three EV patients infected by HPV5 and one by HPV8, with cancers containing mostly or only episomal viral genomes with a deletion. The mutants were compared with the full-length genomes present in the benign lesions of each patient. Deletions affected the L1 and/or L2 open reading frames (ORFs), and extended in the 5' end of the long control region in two cancers. The isolates studied showed a polymorphism of restriction endonuclease cleavage sites and variations in the nucleotide sequence of the E6 ORF and the regions flanking the deletions. However, except for one patient infected by two distinct HPV5 variants, no difference was observed in the nucleotide sequence of isolates cloned from the benign lesions and the cancer of the same patient. This may suggest that point mutations are not involved in tumor progression. Comparison of nucleotide sequence data revealed an unexpectedly high number of nucleotide substitutions among the four HPV5 variants and the HPV8 variant, as compared with HPV5 and HPV8 published sequences. Changes involved 49 of the 457 nucleotides of HPV5 E6 ORF and 14 of the 465 nucleotides of HPV8 E6 ORF. This corresponds to amino acid substitutions affecting 17 of the 157 amino acids of HPV5 E6 proteins and 7 of the 155 amino acids of HPV8 E6 proteins. Half of the substitutions represent nonconservative changes. The variants showing the highest degree of sequence variation were detected in additional EV patients by PCR. This points to the existence of a set of HPV5 and HPV8 stable variants, encoding for multiple allelic forms of the transforming E6 gene.

The role of human papillomavirus in carcinoma

Human papillomaviruses have long been identified as the cause of common warts and condylomata acuminata. Evidence is now accumulating that human papillomaviruses may be involved in not only benign, but also in malignant neoplasms. They might also be significant in the malignant transformation of cutaneous neoplasms. This review examines the oncogenic potential of human papillomaviruses when they are found in carcinomas in various anatomic areas, including the skin.

The primary structure of major viral RNA in a rat cell line transfected with type 47 human papillomavirus DNA and the transforming activity of its cDNA and E6 gene

A transformed cell line (RC335) showing higher saturation cell density was obtained from 3Y1 cells (a fibroblastic cell line of rat) transfected with DNA of human papillomavirus type 47 (HPV-47), an epidermodysplasia verruciformis-associated virus, which our laboratory reported previously. The cell line was found to produce a major and several minor species of viral RNAs. The primary structure of the major viral RNA in RC335 was extensively studied and found to consist of two exons and contain open reading frames (ORFs) E6, E7, and a fused ORF, E1/E4. The major RNA was indicated to play an important role in the transformation of RC335 by an experiment with the recombinant retrovirus designed to produce the RNA containing these ORFs, i.e., the recombinant virus induced transformation similar to that in RC335 upon infection of 3Y1 cells. Furthermore the experiments with recombinant viruses carrying a nonsense mutation or large deletion in the above ORF(s) indicated that E6 was necessary and sufficient for the transformation.

Epidermodysplasia verruciformis in a patient with Hodgkin's disease: characterization of a new papillomavirus type and interferon treatment

A new human papillomavirus (HPV) was discovered in disseminated, macular, pityriasis versicolor-like lesions on the skin of the neck, face, scalp, and pubic region of a 42-year-old male suffering from Hodgkin's disease. Histopathology revealed features characteristic of epidermodysplasia verruciformis (ev). In contrast to classical ev, the lesions were almost exclusively seen in previously irradiated and UV-exposed skin areas. Papillomavirus capsid antigen was demonstrated with the genus-specific antiserum and the patient's serum, which had IgM and IgG antibody titers. HPV DNA was isolated from biopsies and cloned into the vector pIC20H. It proved to be related to ev-associated viruses, showing 23% cross-hybridization with DNA of the closest relative HPV14. The new HPV type was named HPV46. The genome was physically mapped and colinearly aligned with HPV8 DNA to establish its gene organization. Interferon treatment of the patient did not significantly change the clinical picture nor was the concentration of viral DNA per lesion affected. However, no virus capsid antigen was detectable after starting treatment.