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

BACKGROUND: Human papillomaviruses (HPVs) are found in normal skin and in benign and malignant skin conditions. Epidermodysplasia verruciformis (EV) HPV types are those most plausibly linked to the development of squamous cell carcinomas of the skin. OBJECTIVES: To assess the risk of nonmelanoma skin cancer (NMSC) associated with the presence of EV HPV in normal skin in immunocompetent (IC) individuals and renal transplant recipients (RTRs). METHODS: Using a degenerate and nested polymerase chain reaction technique, HPV DNA was sought in 124 normal skin samples from sun-exposed and nonsun-exposed sites, from 39 IC individuals and 38 RTRs, both with and without NMSC. Data were analysed using the Mantel-Haenszel test and by logistic regression analysis. RESULTS: HPV DNA was detected in 58/67 (87%) and 20/57 (35%) samples from renal transplant and IC patients, respectively. There was no difference in either the prevalence or spectrum of HPV types found in sun-exposed and nonsun-exposed normal skin. However, there was significant association between NMSC and the presence of EV HPV DNA. Multivariate analysis provided an odds ratio of 6.41 (95% confidence interval 1.79-22.9) for the association of EV HPV DNA in normal skin (irrespective of site) and NMSC status, even after stratifying for patient group and adjusting for the clustering effect of multiple sampling. Conversely, there was no association between skin cancer status and the presence of cutaneous or mucosal HPV types in either sun-exposed or nonsun-exposed skin. CONCLUSIONS: HPV DNA is widespread in normal adult skin, particularly in transplant patients. In our study, the presence of EV but not cutaneous HPV DNA in normal skin was significantly associated with NMSC status and may prove to be of predictive value for skin cancer risk. These data provide reason to focus on EV HPV types as causal agents in skin cancer.

STEVOR--a multifunctional protein?

The stevor multigene family is the third largest identified in Plasmodium falciparum. Its members have the potential to be involved in antigenic variation and virulence by analogy with the var and rif multigene families. This review highlights recent studies of stevor transcription and expression which show that stevor is distinct from both the var and rif multigene families. STEVOR is expressed during several stages of the lifecycle, and thus may contribute significantly to the long term survival of the parasite.

High frequency of loss of heterozygosity in vulval intraepithelial neoplasia (VIN) is associated with invasive vulval squamous cell carcinoma (VSCC).

Vulval intraepithelial neoplasia (VIN) is thought to be the premalignant phase of human papillomavirus (HPV)-associated vulval squamous cell carcinoma (VSCC). Various molecular events have been suggested as markers for progression from VIN to VSCC, but loss of heterozygosity (LOH) in vulval neoplasia has rarely been studied in this context. We performed LOH analysis by polymerase chain reaction (PCR) amplification of polymorphic microsatellite markers at 6 chromosomal loci (17p13-p53, 9p21-p16, 3p25, 4q21, 5p14 and 11p15). The presence of HPV was assessed using consensus PCR primers and DNA sequencing. To examine any association between LOH and the presence of invasive disease, we analyzed 43 cases of lone VIN III, 42 cases of lone VSCC and 21 cases of VIN with concurrent VSCC. HPV DNA was detected in 95% of lone VIN III samples and 71% of lone VSCC samples. Fractional regional allelic loss (FRL) in VIN associated with VSCC was higher than in lone VIN (mean FRL 0.43 vs. 0.21, p < 0.005). LOH at 3p25 occurred significantly more frequently in HPV-negative VSCC than in HPV-positive VSCC (58% vs. 22%, p < 0.04). These data suggest that genetic instability in VIN, reflected by LOH, may increase the risk of invasion. In addition, molecular events differ in HPV-positive and -negative VSCC and 3p25 may be the site of a tumor suppressor gene involved in HPV-independent vulval carcinogenesis.

Human papillomavirus infection and non-melanoma skin cancer in immunosuppressed and immunocompetent individuals.

The role of human papillomavirus (HPV) in anogenital carcinogenesis is established firmly, but a similar role in non-melanoma skin cancer remains speculative. Certain immunosuppressed individuals have an increased incidence of both viral warts and non-melanoma skin cancer, that has prompted the suggestion that HPV may play a pathogenic role. Differences in the techniques used to detect HPV DNA in skin, however, have led to discrepancies in the prevalence and spectrum of HPV types reported in these malignancies. This study describes the use of a comprehensive degenerate PCR technique to compare the HPV status of 148 Non-melanoma skin cancers from immunosuppressed and immunocompetent individuals. HPV DNA was detected in 37/44 (84.1%) squamous cell carcinomas, 18/24 (75%) basal cell carcinomas and 15/17 (88.2%) premalignant skin lesions from the immunosuppressed group compared with 6/22 (27.2%) squamous cell carcinomas, 11/30 (36.7%) basal cell carcinomas and 6/11 (54. 4%) premalignancies in the immunocompetent group. Epidermodysplasia verruciformis HPV types prevailed in all lesion types from both groups of patients. In immunosuppressed individuals, cutaneous HPV types were also identified at high frequency, and co-detection of multiple HPV types within single tumours was commonly observed. This study represents the largest and most comprehensive analysis of the HPV status of non-melanoma skin cancers yet undertaken; whereas there are clearly significant differences in non-melanoma skin cancers from immunosuppressed and immunocompetent populations, we provide evidence that the prevalence and spectrum of HPV types does not differ in squamous cell carcinomas, basal cell carcinomas or premalignancies within the two populations. These data have important implications for future investigation of the role of HPV in cutaneous carcinogenesis at a functional level.

Degenerate and nested PCR: a highly sensitive and specific method for detection of human papillomavirus infection in cutaneous warts.

The role of human papillomavirus (HPV) in anogenital carcinogenesis is firmly established, but evidence that supports a similar role in skin remains speculative. Immunosuppressed renal transplant recipients have an increased incidence of viral warts and nonmelanoma skin cancer, and the presence of HPV DNA in these lesions, especially types associated with the condition epidermodysplasia verruciformis (EV), has led to suggestions that HPV may play a pathogenic role. However, differences in the specificities and sensitivities of techniques used to detect HPV in skin have led to wide discrepancies in the spectrum of HPV types reported. We describe a degenerate nested PCR technique with the capacity to detect a broad spectrum of cutaneous, mucosal, and EV HPV types. In a series of 51 warts from 23 renal transplant recipients, this method detected HPV DNA in all lesions, representing a significant improvement over many previously published studies. Cutaneous types were found in 84.3% of warts and EV types were found in 80.4% of warts, whereas mucosal types were detected in 27.4% of warts. In addition, the method allowed codetection of two or more distinct HPV types in 94.1% of lesions. In contrast, single HPV types were detected in all but 1 of 20 warts from 15 immunocompetent individuals. In summary, we have established a highly sensitive and comprehensive degenerate PCR methodology for detection and genotyping of HPV from the skin and have demonstrated a diverse spectrum of multiple HPV types in cutaneous warts from transplant recipients. Studies designed to assess the significance of these findings to cutaneous carcinogenesis are under way.

Simian virus 40 and human pleural mesothelioma.

BACKGROUND: An aetiological role for Simian virus 40 (SV40) in malignant mesothelioma has been suggested from studies in the USA and the UK but results have been conflicting. A study was undertaken to look for evidence of SV40 in stored tissue samples from pleural mesotheliomas. METHODS: DNA was extracted from paraffin embedded tissue. The presence of DNA was established by amplification of a 250 bp product from the betaglobin gene. Primers PYV.F and PYV.R were used in a concentration of 50 per mol each per reaction to amplify a 172 bp fragment of a conserved region of SV40 that codes for a portion of large T antigen that is common to SV40 and other polyoma viruses. RESULTS: Twelve of the 17 samples contained amplifiable betaglobin DNA. None of the samples (0/12, 95% CI 0 to 26.5%) was positive for the polyoma large T antigen. CONCLUSIONS: These results do not lend any support to the hypothesis that SV40 infection may be aetiologically relevant to the increasing incidence of mesothelioma in the UK.

Detection and typing of human papillomaviruses in mucosal and cutaneous biopsies from immunosuppressed and immunocompetent patients and patients with epidermodysplasia verruciformis: a unified diagnostic approach.

AIM: To develop a unified diagnostic approach for the detection of human papillomavirus (HPV) DNA in skin and mucosal biopsies from both immunocompetent and immunosuppressed individuals using a degenerate polymerase chain reaction (PCR) method. METHODS: The sensitivity and specificity of three published degenerate primer sets (HVP2/B5 and F14/B15; MY09/MY11; CP62/69 outer and CP65/68 nested primer pairs) were evaluated in PCR reactions with serial dilutions of 12 representative cloned HPV types. This combination of primers was then used to detect HPV DNA in 49 benign and malignant lesions of cutaneous and mucosal origin from immunosuppressed, immunocompetent, and epidermodysplasia verruciformis (EV) patients, and compared with detection rates using single primer sets alone. RESULTS: The observed sensitivity of MY09/MY11 and CP62/69 + CP65/68 was high for mucosal and EV HPV types, respectively. The sensitivity of all primer sets for cutaneous types was low, but nonetheless the use of this combination of primers allowed HPV DNA detection in all of the benign warts analysed. Several mixed infections were also identified. A high prevalence of HPV DNA was similarly detected in squamous cell carcinomas from immunocompromised patients; the HPV types found were exclusively EV related. CONCLUSIONS: The use of a combined degenerate primer PCR approach considerably improves HPV DNA detection over individual primer sets and allows detection of mixed infections. The findings may help explain the discrepancies in published reports relating to HPV DNA detection in benign and malignant skin lesions. Further modifications to this method are in progress which should significantly improve comprehensive HPV detection and typing for diagnostic purposes.

Detection of human papillomavirus DNA in PUVA-associated non-melanoma skin cancers.

Psoralen and UVA (PUVA) photochemotherapy is associated with a dose-dependent increased risk of nonmelanoma skin cancer in patients treated for psoriasis. Like ultraviolet B radiation, PUVA is both mutagenic and immunosuppressive and may thus act as a complete carcinogen; however, the reversed squamous to basal cell carcinoma ratio (SCC:BCC) in PUVA-treated patients, also seen in immunosuppressed renal transplant recipients, suggests a possible cofactor role for human papillomavirus (HPV) infection. In this study we examine a large series of benign and malignant cutaneous lesions for the presence of HPV DNA from patients treated with high dose (> or =500 J per cm2) ultraviolet A. A panel of degenerate primers based on the L1 (major capsid protein) open reading frame was employed, designed to detect mucosal, cutaneous, and epidermodysplasia verruciformis HPV types with high sensitivity and specificity. HPV DNA was detected in 15 of 20 (75%) non-melanoma skin cancer, seven of 17 (41.2%) dysplastic PUVA keratoses, four of five (80%) skin warts, and four of 12 (33%) PUVA-exposed normal skin samples. The majority of HPV positive lesions contained epidermodysplasia verruciformis-related HPV including HPV-5, -20, -21, -23, -24, and -38. Possible novel epidermodysplasia verruciformis types were identified in further lesions. Mixed infection with epidermodysplasia verruciformis, cutaneous, and/or mucosal types was present in six of 30 (20%) of all HPV positive lesions, including in normal skin, warts, dysplastic PUVA keratoses, and squamous cell carcinomas. The prevalence and type of HPV infection in cutaneous lesions from PUVA-treated patients is similar to that previously reported in renal transplant-associated skin lesions, and suggests that the role of HPV in PUVA-associated carcinogenesis merits further study.

Active psoriasis and profound CD4+ lymphocytopenia.

We report the case of a patient with a long-standing history of widespread chronic plaque psoriasis, who was recently found to have a profound CD4+ lymphocytopenia. He is human immunodeficiency virus (HIV) negative. His psoriasis remains active and widespread, and he has had 60 cutaneous malignancies, including many squamous cell carcinomas, excised over the last 10 years. In the past he has had numerous cutaneous viral warts. Despite a low peripheral blood CD4+ T-cell count, similar numbers of activated T cells, identified by double labelling for CD4 and HLA-DR antigens, were found in the epidermis of our patient as other individuals with psoriasis. Thus, there appear to be sufficient activated CD4+ T cells in our patient's psoriatic plaques to maintain the psoriatic process.