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1.
J Clin Microbiol ; 41(6): 2763-7, 2003 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12791926

RESUMEN

Human papillomavirus (HPV) DNA loads of six oncogenic HPV types were measured by real-time PCR in cervical scrapes of human immunodeficiency virus (HIV)-infected and uninfected women. In both groups, HPV loads increased with the grade of cervical disease. HIV infection did not affect HPV loads in low-grade lesions but was associated with significantly higher HPV loads in severe dysplasia; highest loads were found in advanced HIV disease. Our data reflect the aggressive course of HPV infection in HIV-positive women.


Asunto(s)
ADN Viral/análisis , Infecciones por VIH/complicaciones , Papillomaviridae/aislamiento & purificación , Infecciones por Papillomavirus/virología , Enfermedades del Cuello del Útero/virología , Neoplasias del Cuello Uterino/virología , Adolescente , Adulto , Anciano , Progresión de la Enfermedad , Femenino , Infecciones por VIH/virología , Humanos , Persona de Mediana Edad , Papillomaviridae/clasificación , Papillomaviridae/genética , Reacción en Cadena de la Polimerasa , Enfermedades del Cuello del Útero/fisiopatología , Neoplasias del Cuello Uterino/fisiopatología
2.
Br J Dermatol ; 147(4): 793-6, 2002 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-12366433

RESUMEN

We describe a patient with a 9-year history of generalized eruptive keratoacanthoma (KA) of the Grzybowski type whose multiple skin lesions showed steady progression, resulting in a sclerotic, mask-like facial expression and ectropion. Eleven tumour biopsies representing lesions of different stages and localizations (erupting and regressing KAs, biopsies from non-involved light-protected and light-exposed skin, dermatosclerosis and squamous cell carcinomas) were analysed for human papillomavirus (HPV) sequences using a polymerase chain reaction approach capable of detecting the majority of all presently known HPV genotypes. None of the biopsy specimens proved to be HPV-positive, although HPV was detected in weakly and heavily affected control specimens by the method applied. These findings suggest an HPV-independent aetiology of this rare type of multiple KA.


Asunto(s)
Queratoacantoma/virología , Papillomaviridae/aislamiento & purificación , Neoplasias Cutáneas/virología , Anciano , Progresión de la Enfermedad , Neoplasias Faciales/virología , Facies , Femenino , Estudios de Seguimiento , Humanos
3.
Cancer ; 92(11): 2875-84, 2001 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-11753961

RESUMEN

BACKGROUND: Oncogenic human papillomaviruses (HPV) DNA have repeatedly been observed in many head and neck carcinomas (HNSCCs), and HPV infections are currently considered a possible factor in the etiology of these tumors. However, the reported prevalences of HPV-DNA in HNSCC are variable. In the current study the authors used highly sensitive polymerase chain reactions (PCRs) to analyze the occurrence of viral sequences in 98 carefully stratified HNSCCs. The authors determined the load and localization of HPV DNA in a subset of tonsillar carcinomas and their metastases. METHODS: Nested PCR and an HPV16 specific single step PCR were used to screen 98 HNSCCs for HPV DNA for genital- and Epidermodysplasia verruciformis (EV)-associated HPVs. Typing was performed by direct sequencing and/or sequencing of cloned amplimers. In two patients HPV16 subtypes in tonsillar carcinomas and their metastases were compared by amplification and sequencing of the long control region of the virus. In a subset of HPV16 positive tonsillar carcinomas and their metastases, localization and viral load were determined using laser assisted microdissection and real time fluorescent PCR, respectively. RESULTS: Altogether 25 HNSCCs (26%) were found to be HPV positive. Stratified according to the tumor localization, the frequency of HPV positive lesions was 18% in the oral cavity, 45% for oropharynx, 25% for hypopharynx, 8% for nasopharynx, and 7% for larynx. The highest HPV DNA prevalence (58%) was found in tonsillar carcinomas. The high risk HPV type 16 was found in 84% of positive HNSCCs, in 14% of which EV-associated HPVs were detected. Human papillomavirus sequences were detected in 64% of biopsies with normal mucosa from 11 patients with positive carcinomas. As a control group, 14 tumor free tonsils were analyzed. In none of these specimens were HPV sequences detected. Viral long transcriptional control region sequences in homologous metastases were identical with those in primary tumors and the load values in both locations were roughly comparable. Viral loads differed substantially in different areas of one tumor. Statistical evaluation of data related to clinicopathologic parameters showed a significant linkage of HPV with tonsillar carcinomas compared to other locations. Furthermore, a significant correlation of HPV status of tonsillar carcinomas with tumor grading and alcohol consumption was found. CONCLUSIONS: Our study shows a preferential association of HPV-DNA with tonsillar carcinomas. The data support the view of HPV negative and positive tonsillar carcinomas being different tumor entities and conventional cancer risk factors being of less importance in HPV-infected individuals. The HPV genome is located in the cancer cells, whereas the infection of normal mucosa is a rare event. Data on quantification of HPV16 in tonsillar tumors and their metastases showed mean viral loads comparable to other HPV associated malignancies.


Asunto(s)
ADN Viral/análisis , Papillomaviridae , Infecciones por Papillomavirus/epidemiología , Neoplasias Tonsilares/virología , Infecciones Tumorales por Virus/epidemiología , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Papillomaviridae/genética , Papillomaviridae/fisiología , Infecciones por Papillomavirus/etiología , Prevalencia , Análisis de Secuencia de ADN , Estadística como Asunto , Neoplasias Tonsilares/complicaciones , Infecciones Tumorales por Virus/etiología , Carga Viral
6.
Br J Dermatol ; 144(5): 1044-9, 2001 May.
Artículo en Inglés | MEDLINE | ID: mdl-11359395

RESUMEN

BACKGROUND: Netherton's syndrome (NS) is a hereditary disorder with dermatological signs (e.g. ichthyosis) and a complex immunological dysfunction. In immunodeficient individuals human papillomavirus (HPV) types are associated with carcinomas on non-mucosal sites. OBJECTIVES: To study the presence of HPV infection in different skin lesions of three male NS patients and to investigate a possible association between HPV and malignancies in NS. METHODS: Patient 1 had extraordinary widespread multiple skin carcinomas on sunlight-exposed areas, as well as common viral warts. Patient 2 showed disseminated viral plane warts that resolved spontaneously, and patient 3 was free of skin lesions suspicious for HPV infection; only pseudoepitheliomatous wart-like lesions as a symptom of ichthyosis were apparent. We performed nested polymerase chain reaction analysis of DNA from benign and malignant skin lesions and HPV-8 serology in these three patients. RESULTS: Antibodies to HPV-8 were not detectable in our patients; however, seven of 22 (31%) biopsies of the three NS patients were positive for HPV DNA. Epidermodysplasia verruciformis (EV) -associated HPV types and normal cutaneous types (HPV-2, HPV-28) were detected. Interestingly, only the patient with cutaneous carcinomas harboured, preferentially in malignant lesions, EV-HPV types (HPV-19, 23, 38 and HPV-RTRX9, closely related to EV-HPVs), whereas plane warts of patient 2 were positive for HPV-28. The pseudoepitheliomatous skin lesions were HPV-DNA negative in all investigated probes. CONCLUSIONS: These data in NS patients further confirm an association of EV-HPVs with non-melanoma skin cancer (NMSC) and suggest a possible carcinogenic role similar to that assumed for NMSC in transplant recipients. A complex immunological disorder facilitating EV-HPV infection, negative HPV serology and photochemotherapy may all have contributed to the unusual occurrence of multiple cancers in one of our NS patients.


Asunto(s)
Ictiosis/complicaciones , Papillomaviridae/aislamiento & purificación , Infecciones por Papillomavirus/complicaciones , Neoplasias Cutáneas/virología , Infecciones Tumorales por Virus/complicaciones , Adulto , ADN Viral/análisis , Humanos , Enfermedades del Sistema Inmune/complicaciones , Masculino , Infecciones Oportunistas/complicaciones , Papillomaviridae/clasificación , Lesiones Precancerosas/virología , Síndrome
7.
J Invest Dermatol ; 115(1): 124-8, 2000 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10886519

RESUMEN

DNA of human papillomaviruses has frequently been detected in nonmelanoma skin cancers, raising the question of a possible causal contribution of these tumor viruses to skin carcinogenesis. Basal cell carcinomas are the most common nonmelanoma skin cancers; however, so far they are only poorly analyzed with regard to human papillomavirus infection. We searched for human papillomavirus-DNA in 69 biopsies from 61 immunocompetent basal cell carcinoma patients from two geographic locations in Europe using six different polymerase chain reaction primer systems. We could demonstrate human papillomavirus-DNA in 43.5% of the tested tumors. Human papillomavirus positivity did not seem to correlate with the duration of disease or patients' age. The vast majority of virus types in the biopsies belonged to the group of epidermodysplasia verruciformis-associated human papillomavirus. Of 31 sample pairs tested for human papillomavirus-DNA in tumors as well as in perilesional healthy skin, seven carried viral sequences in lesional and healthy skin and three only in the basal cell carcinoma. Six of the seven human papillomavirus-positive basal cell carcinoma/healthy skin pairs contained identical human papillomavirus types in tumors and histologically normal tissue. Forty basal cell carcinoma patients were additionally analyzed for IgG antibodies against virus-like particles of three representative epidermodysplasia verruciformis-human papillomavirus types: 8, 15, and 36. No statistically significant differences could be detected between human papillomavirus antibody prevalences of basal cell carcinoma patients and of dermatologically healthy individuals. Moreover, serologic findings did not correlate with the detection of specific human papillomavirus types in tumors. Our results seem to suggest that the occurrence of human papillomavirus-DNA in basal cell carcinoma does not reflect a major etiologic role of human papillomavirus in this cancer.


Asunto(s)
Carcinoma Basocelular/genética , ADN Viral/análisis , Papillomaviridae/genética , Neoplasias Cutáneas/genética , Anciano , Anciano de 80 o más Años , Anticuerpos Antivirales/sangre , Biopsia , Carcinoma Basocelular/patología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Papillomaviridae/inmunología , Neoplasias Cutáneas/patología
8.
Br J Dermatol ; 142(1): 103-9, 2000 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-10651702

RESUMEN

Epidermodysplasia verruciformis-associated human papillomaviruses (EV-HPVs) are possibly involved in the development of actinic keratoses and may play a part in the pathogenesis of squamous cell carcinoma (SCC) of the skin, as the DNA of these viruses is frequently detected in biopsies of such lesions. Properly designed epidemiological studies, using serological tests to investigate the role of infection with EV-HPVs in cutaneous oncogenesis, are still rare. An IgG-specific enzyme-linked immunosorbent assay using virus-like particles composed of the major capsid protein L1 of the EV-specific HPV 8 (HPV 8 VLPs) was developed and used to test the seroprevalence of HPV 8 in 114 inhabitants of a tropical island, of whom 13 had developed SCC, and 19 had developed basal cell carcinoma. Gender, age, eye and hair colour, sun exposure and number of actinic keratoses were recorded for all individuals. The presence of antibodies against HPV 8 VLPs was associated with the development of large numbers of actinic keratoses. After adjusting for gender, age, eye and hair colour, and sun exposure, the odds ratio to develop 37 (the median in this dataset) or more actinic keratoses in the presence of antibodies against HPV 8 VLPs was 2.3 (95% confidence interval: 1.0; 5.3). Similarly, after adjustment for the same factors, the presence of these antibodies was associated with SCC with an odds ratio of 3.1 (0.74; 13.3), but the small number of individuals with SCC does not permit any definite conclusions. The presence of these antibodies did not appear to be associated with basal cell carcinoma as, after adjustment for the same factors, the odds ratio was 0.73 (0.23; 2.4). This study provides serological evidence that infection with EV-HPVs may play a part in the pathogenesis of actinic keratoses. The role of EV-HPVs in the development of SCC, however, remains to be elucidated.


Asunto(s)
Carcinoma de Células Escamosas/virología , Epidermodisplasia Verruciforme/virología , Queratosis/virología , Papillomaviridae , Neoplasias Cutáneas/virología , Adulto , Anciano , Anciano de 80 o más Años , Anticuerpos Antivirales/análisis , Carcinoma de Células Escamosas/inmunología , Ensayo de Inmunoadsorción Enzimática , Epidermodisplasia Verruciforme/inmunología , Femenino , Humanos , Inmunoglobulina G/análisis , Queratosis/inmunología , Masculino , Persona de Mediana Edad , Papillomaviridae/inmunología , Luz Solar/efectos adversos
9.
J Invest Dermatol ; 113(1): 122-6, 1999 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10417630

RESUMEN

Epidermodysplasia verruciformis-associated human papillomaviruses and in particular human papillomavirus type 5 were recently shown to be highly prevalent in psoriatic skin. We have analyzed lesional skin from 54 psoriasis patients for infections with genital-specific and epidermodysplasia verruciformis-specific human papillomaviruses to define the spectrum of involved human papillomavirus types and to test if it is influenced by psoralen ultraviolet A therapy. Using polymerase chain reaction analysis we could detect human papillomavirus sequences in skin lesions of 83% of the tested patients. In contrast, human papillomavirus-DNA was only demonstrated in 19% of skin samples from 42 dermatologically healthy, immunocompetent individuals. Sequence analysis of the polymerase chain reaction amplimers revealed 14 human papillomavirus types, all belonging to the epidermodysplasia verruciformis or epidermodysplasia verruciformis-related papillomaviruses. Only in one case we identified sequences related to those of genital viruses, which, however, represented a putatively new human papillomavirus type. The most prevalent human papillomavirus type in our patient series was human papillomavirus type 36, found in 62% of the patients positive for human papillomavirus-DNA, followed by human papillomavirus type 5 (38%) and human papillomavirus type 38 (24%). Multiple infections with two to five different human papillomavirus types could be detected in skin samples of 63% of the analyzed patients. The overall human papillomavirus detection rate did not differ significantly between patients which have been subjected to psoralen ultraviolet A photochemotherapy or solely treated with topical preparations (77 vs 89%). Human papillomavirus type 5, however, could be detected significantly more frequent in lesions of psoralen ultraviolet A-treated patients (p < 0.001). Our data strongly argue for infections with epidermodysplasia verruciformis-specific papillomaviruses being an almost consistent feature of the lesional psoriatic skin and substantiate the importance of further studies to elucidate a possible involvement of human papillomaviruses in psoriasis pathology.


Asunto(s)
Terapia PUVA , Papillomaviridae , Infecciones por Papillomavirus/tratamiento farmacológico , Psoriasis/tratamiento farmacológico , Infecciones Tumorales por Virus/tratamiento farmacológico , Adolescente , Adulto , Anciano , Secuencia de Aminoácidos , Secuencia de Bases , Biopsia , ADN Viral/genética , Epidermodisplasia Verruciforme/virología , Humanos , Persona de Mediana Edad , Datos de Secuencia Molecular , Papillomaviridae/clasificación , Papillomaviridae/genética , Prevalencia , Psoriasis/epidemiología , Psoriasis/virología , Alineación de Secuencia , Análisis de Secuencia de ADN , Homología de Secuencia de Aminoácido , Homología de Secuencia de Ácido Nucleico , Piel/patología , Piel/virología , Enfermedades Cutáneas Virales/tratamiento farmacológico , Enfermedades Cutáneas Virales/patología
10.
J Invest Dermatol ; 111(4): 696-701, 1998 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9764856

RESUMEN

There is increasing evidence for widespread occurrences of infection with Epidermodysplasia verruciformis-related human papillomaviruses, both in the general population and in immunosuppressed patients. In order to test for the prevalence of antibodies directed against the native L1 epitopes exposed on the surface of the virions, we have established an IgG-specific enzyme-linked immunosorbent assay with L1 virus-like particles of the Epidermodysplasia verruciformis-specific human papillomavirus 8 as antigen to screen 567 representative serum samples from the general population and immunosuppressed/dermatologic patients. Among healthy European donors (n = 210), 7.6% were found to be seropositive. In a group of renal transplant recipients (n = 185) the antibody prevalence was elevated to 21.1%, irrespective of the presence or absence of skin cancer. High positivity rates could be detected among (i) immunocompetent patients with nonmelanoma skin tumors (45.6%, n = 79) and (ii) Psoralene/UVA treated psoriasis patients (42.9%, n = 42). In contrast, anti-human papillomavirus 8-virus-like particle antibodies were found in only 6.8% of Hodgkin lymphoma patients (n = 44).


Asunto(s)
Epidermodisplasia Verruciforme/virología , Papillomaviridae , Infecciones por Papillomavirus/inmunología , Neoplasias Cutáneas/etiología , Infecciones Tumorales por Virus/inmunología , Anticuerpos Antivirales/análisis , Ensayo de Inmunoadsorción Enzimática , Humanos , Tolerancia Inmunológica , Inmunocompetencia , Trasplante de Riñón/inmunología , Proteínas Oncogénicas Virales/química , Proteínas Oncogénicas Virales/aislamiento & purificación , Papillomaviridae/inmunología , Prevalencia , Factores de Riesgo , Neoplasias Cutáneas/epidemiología , Neoplasias Cutáneas/inmunología
11.
J Gen Virol ; 78 ( Pt 12): 3287-95, 1997 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9400979

RESUMEN

Human papillomavirus type 8 (HPV-8) is a strictly cutaneous oncogenic virus known to induce malignant skin lesions in epidermodysplasia verruciformis patients. Our study shows that sequences surrounding transcription start sites of the HPV-8 oncogene E6 (nt 175-179) and comprising the presumable CCAAC and TATA boxes of the E6 promoter P175 contain a cluster of four motifs similar to the DNA recognition site of the multifunctional cellular transcription factor yin-yang 1 (YY1). Using DNase I footprinting and gel retardation tests it could be demonstrated that three of these motifs indeed act as YY1 binding sites. To test their functional relevance for P175 activity, engineered YY1 binding site mutants were analysed in the context of a P175 test vector using transient expression assays with human keratinocytes. YY1 turned out to exert both positive and negative effects upon the activity of the HPV-8 E6 promoter; binding of YY1 to a site upstream of the promoter's cap-position (BS1) activated transcription, whereas the downstream site (BS2) mediated repression. The second downstream YY1 binding site (BS3) seemed to play an auxiliary role, enhancing the negative effect of YY1 BS2. These observations define YY1 as an important cellular protein involved in the control of E6 oncogene expression of the skin-specific 'high risk' HPV-8 and emphasize the potential regulatory role of sequences located downstream of the transcription start site.


Asunto(s)
Proteínas de Unión al ADN/genética , Regulación Viral de la Expresión Génica , Proteínas Oncogénicas Virales/genética , Papillomaviridae/genética , Factores de Transcripción/genética , Factores de Unión al ADN Específico de las Células Eritroides , Humanos , Regiones Promotoras Genéticas/genética , Células Tumorales Cultivadas , Factor de Transcripción YY1
12.
J Virol ; 68(6): 3612-9, 1994 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-8189499

RESUMEN

The noncoding region of the highly oncogenic, epidermodysplasia verruciformis-associated human papillomavirus type 8 contains a negative regulatory element (NRE). Quantitative RNase protection analysis confirmed that the NRE sequence acts as a silencer of transcription. A 38-bp sequence upstream of late promoter P7535 down-regulated expression from the homologous P7535 promoter, as well as the heterologous tk gene promoter, independently of its orientation relative to the test promoters. It also reduced gene expression when cloned downstream of the transcription units. Transient expression assays with keratinocytes and fibroblasts of epidermodysplasia verruciformis patients and controls demonstrated that the NRE activity is not cell specific. Gel retardation tests suggested that NRE specifically interacts with only one nuclear factor. Mutational analysis identified three NRE mutants which no longer formed a detectable DNA-protein complex but still repressed transcription, indicating that protein-DNA interaction is not relevant for the silencer function. The NRE contains a binding site of viral trans activator protein E2. It was shown that expression of E2 overrides the inhibitory effect of the NRE sequences. Binding of E2 and that of the cellular factor were mutually exclusive. The bifunctional nature of NRE acting as a silencer and a target site for viral trans activator E2 offers an interesting opportunity to regulate the switch from early to late transcription in the human papillomavirus life cycle.


Asunto(s)
Genes Virales , Papillomaviridae/genética , Regiones Promotoras Genéticas , Secuencia de Bases , Células Cultivadas , ADN Viral/genética , ADN Viral/metabolismo , Epidermodisplasia Verruciforme/virología , Regulación Viral de la Expresión Génica , Genes Reguladores , Humanos , Datos de Secuencia Molecular , Mutagénesis Sitio-Dirigida , Proteínas Nucleares/metabolismo , Proteínas Oncogénicas Virales/genética , Proteínas Oncogénicas Virales/metabolismo , Papillomaviridae/clasificación , Papillomaviridae/metabolismo , Unión Proteica , Transactivadores/genética , Transactivadores/metabolismo , Transcripción Genética
13.
EMBO J ; 13(6): 1460-6, 1994 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-8137827

RESUMEN

Human papillomavirus type 16 (HPV16) induces squamous intraepithelial lesions of the cervical mucosa which may develop into invasive cancer. The expression of viral oncogenes in advanced neoplasias appears increased relative to the proliferating cell layers of low grade lesions raising questions about molecular mechanisms of deregulation of transcription. In a lymph node metastasis of a cervical cancer, we observed full-length HPV16 plasmids and molecules with a small deletion, which was mapped to the long control region (LCR). Both wild type and shortened LCR were amplified by PCR, cloned into the promoter test plasmid pBLCAT6 and sequenced to identify a 107 bp deletion from position 7794 to 7901 in the short LCR. CAT expression in cervical cancer-derived HT3, SiHa and CaSki cells appeared 5- to 6-fold increased under the control of the short LCR. This could be traced back to elevated levels of mRNA initiated at the viral oncogene promoter. A slight further increase in CAT expression was noted in the presence of the HPV16 E2 protein which is probably due to the deletion of one E2 binding site and consequent relief from E2 repression. Computer-assisted sequence analysis and band-shift experiments with purified YY1 protein and wild type or mutated oligonucleotides identified four binding sites for this cellular transcriptional repressor within the promoter-proximal segment of the HPV16 LCR, three of which were removed by the deletion. A LCR fragment comprising these YY1 binding sites was cloned in front of the heterologous thymidine kinase gene promoter and suppressed CAT expression 3- to 4-fold.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Proteínas de Unión al ADN/metabolismo , Proteínas Oncogénicas Virales/genética , Papillomaviridae/genética , Regiones Promotoras Genéticas , Proteínas Represoras , Factores de Transcripción/metabolismo , Neoplasias del Cuello Uterino/genética , Secuencia de Bases , Sitios de Unión , Cromosomas Humanos , ADN Viral/metabolismo , Factores de Unión al ADN Específico de las Células Eritroides , Femenino , Regulación Viral de la Expresión Génica , Humanos , Datos de Secuencia Molecular , Mutación , Proteínas E7 de Papillomavirus , Eliminación de Secuencia , Transcripción Genética , Células Tumorales Cultivadas , Neoplasias del Cuello Uterino/microbiología , Factor de Transcripción YY1
16.
Virology ; 196(2): 674-81, 1993 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-8396805

RESUMEN

Human papillomavirus (HPV) 8 belongs to the HPV types frequently associated with skin cancers of Epidermodysplasia verruciformis (EV)-patients. There are 33 nucleotides (M33 motif) in the 5'-part of the non-coding regulatory region of HPV8, which appear highly conserved among EV-specific HPVs and are consistently followed by an AP1 binding site. These sequences were shown to constitute an essential activator of transcription driven by the HPV8 late promoter P7535. The M33/AP1 element displayed properties of a constitutive enhancer, being also able to stimulate the activity of the heterologous thymidine kinase promoter in a position-independent manner. No protein binding could be detected within the 5'-part of the M33/AP1 region, which contributed significantly to the overall activity of the HPV8 enhancer. As shown by DNasel-footprinting, the central and the 3'-part of the enhancer region were involved in interactions with nuclear proteins. Three specific complexes could be observed in gel retardation tests with nuclear extracts from epithelial cells. One of these interactions involved the AP1 protein. Analysis of deletion and point mutations revealed binding of the AP1 protein to be essential for transcriptional activation, but DNA-protein interactions within M33 were important for maximal stimulation. The response to the phorbol ester TPA also required a cooperation of M33 and AP1.


Asunto(s)
Epidermodisplasia Verruciforme/microbiología , Regulación Viral de la Expresión Génica , Papillomaviridae/genética , Secuencias Reguladoras de Ácidos Nucleicos/genética , Transcripción Genética , Secuencia de Bases , Cloranfenicol O-Acetiltransferasa/biosíntesis , Cloranfenicol O-Acetiltransferasa/genética , Análisis Mutacional de ADN , Humanos , Datos de Secuencia Molecular , Ésteres del Forbol/farmacología , Mutación Puntual , Proteínas Recombinantes de Fusión/biosíntesis , Eliminación de Secuencia , Factor de Transcripción Sp1 , Timidina Quinasa/genética , Transcripción Genética/efectos de los fármacos , Células Tumorales Cultivadas
17.
J Virol ; 66(6): 3485-93, 1992 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-1316464

RESUMEN

Human papillomavirus type 8 (HPV8) belongs to the HPV types associated with skin carcinomas of patients with epidermodysplasia verruciformis (EV). Its noncoding regulatory sequences (NCR) were shown to drive the expression of the reporter gene chloramphenicol acetyltransferase (cat) in transient assays with human epithelial cells (HT3 cells). This constitutive activity could be enhanced by coexpression of the HPV8 transactivator protein E2. The analysis of 5' deletions of the NCR showed that the EV-specific sequence motif M33 and the neighboring AP1 site are essential for the promoter activity, whereas 44 nucleotides located immediately upstream of M33 are strongly inhibitory. The same effects were observed in simian virus 40-immortalized fetal keratinocytes (SV61 cells) and spontaneously immortalized skin keratinocytes (HaCaT cells). By using primer extension and RNase protection analyses two promoters could be identified within the HPV8 NCR. A nested set of weak signals, corresponding to start sites between positions 175 to 179, represented the previously described E6 promoter. The vast majority of transcripts was initiated at position 7535 and shown to undergo processing at an NCR-internal splice donor (positions 1 to 8). The promoter P7535 is similar to late promoters of other skin-associated papillomaviruses as far as localization, transcript structure, and sequence characteristics are concerned. To confirm that P7535-initiated transcripts proceed indeed to the L1 gene for the major capsid protein, viral mRNAs from an HPV8-induced lesion of a patient with EV were characterized by RNase protection and sequence analysis of polymerase chain reaction-amplified cDNAs. The NCR leader (positions 7535 to 4) appeared in two messages with three exons each. The third exon started with the second ATG codon of L1 in both cases; the short central exons from the 3' part of the early coding region were defined by a common splice acceptor site (position 3303) and different splice donor sites (positions 3443 and 3704).


Asunto(s)
Regulación Viral de la Expresión Génica , Papillomaviridae/genética , Regiones Promotoras Genéticas/genética , Transcripción Genética , Infecciones Tumorales por Virus/genética , Adulto , Secuencia de Bases , Cloranfenicol O-Acetiltransferasa/biosíntesis , Análisis Mutacional de ADN , Epidermodisplasia Verruciforme/microbiología , Femenino , Humanos , Datos de Secuencia Molecular , Proteínas Oncogénicas Virales/metabolismo , Precursores del ARN/genética , Empalme del ARN , Neoplasias Cutáneas/microbiología
18.
J Gen Virol ; 72 ( Pt 12): 2989-97, 1991 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-1662691

RESUMEN

The non-coding region (NCR) of the epidermodysplasia verruciformis (EV)-associated human papillomavirus 8 (HPV-8) has been investigated for sequence-specific DNA-protein interactions with nuclear proteins from epithelial HeLa cells. Using DNase I protection analysis 18 footprints could be found within the HPV-8 NCR, covering altogether over 60% of both DNA strands. Several footprints coincided with the known binding sites of transcription factors (NF1, AP1, octamer and PEA3 consensus sequences); the other displayed no obvious similarities in this regard. The overall distribution of sequences involved in DNA-protein interactions differed clearly from the binding patterns reported for other HPVs. Parts of the two binding sites for the viral trans-activator protein E2 were shown to interact with non-E2 factors. The EV-specific NCR motifs M33, M29 and A/T box were all involved in protein binding. By comparing the footprints within the respective motifs of the closely related types HPV-8 and -19, quantitative and qualitative differences were detected for M33 and the A/T box.


Asunto(s)
ADN Viral/metabolismo , Proteínas de Unión al ADN/metabolismo , Epidermodisplasia Verruciforme/microbiología , Papillomaviridae/genética , Secuencia de Bases , Sitios de Unión , Dermatoglifia del ADN , Proteínas de Unión al ADN/genética , Genes Virales , Células HeLa , Humanos , Datos de Secuencia Molecular
19.
Dermatol Clin ; 9(2): 267-76, 1991 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-1647905

RESUMEN

A variety of HPV types infect the anogenital mucosa, giving rise to lesions that differ in clinical appearance, histology, and risk of malignant progression. Human papillomavirus type 16 is distinguished by a strong association with high-grade intraepithelial neoplasia and the greatest prevalence in anogenital malignancy. Most cancers appear to have a multifactorial cause, and HPV infection alone is probably insufficient for malignant transformation. The consistent association between HPV infection and anogenital cancers emphasizes that the papillomaviruses may have a necessary role in carcinogenesis, however. Hence, there is a prospect that vaccination programs may one day allow public health control of HPV infection, thereby eliminating an important risk factor.


Asunto(s)
Neoplasias del Ano/microbiología , Neoplasias de los Genitales Femeninos/microbiología , Neoplasias de los Genitales Masculinos/microbiología , Papillomaviridae , Infecciones Tumorales por Virus , Animales , Neoplasias del Ano/patología , Neoplasias del Ano/prevención & control , Condiloma Acuminado/microbiología , Condiloma Acuminado/patología , Femenino , Neoplasias de los Genitales Femeninos/patología , Neoplasias de los Genitales Femeninos/prevención & control , Neoplasias de los Genitales Masculinos/patología , Neoplasias de los Genitales Masculinos/prevención & control , Humanos , Masculino , Infecciones Tumorales por Virus/patología , Infecciones Tumorales por Virus/prevención & control , Vacunación
20.
Int J Cancer ; 43(1): 41-4, 1989 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-2536006

RESUMEN

Human papillomavirus (HPV) 16 is most prevalent in cervical cancers and also persists in metastases. We examined HPV16-DNA-positive primary cancers and several lymph nodes from each of 14 patients to evaluate the use of HPV16 DNA as a diagnostic marker for the detection of early node involvement. The HPV16 DNA was exclusively integrated in 39% of the primary cancers, predominantly episomal in 36%, and integrated and extrachromosomal to a similar extent in 25%. Thirteen of 16 involved lymph nodes contained HPV16 sequences. Integrated viral DNA showed the same pattern in primary tumors and in metastases. The level of extrachromosomal HPV16 DNA, however, appeared to be considerably reduced in some nodes. HPV16 DNA was also detected in 18 out of 59 histologically negative lymph nodes. This result recommends nucleic acid hybridization as a sensitive method for the detection of HPV-DNA-positive cancer cells. The prognostic significance of viral sequences in histologically negative nodes remains to be established.


Asunto(s)
Biomarcadores de Tumor/análisis , ADN Viral/análisis , Ganglios Linfáticos/microbiología , Neoplasias del Cuello Uterino/microbiología , Southern Blotting , Femenino , Humanos , Metástasis Linfática , Papillomaviridae/genética
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