Genital Human Papillomavirus Infection in women from Florianópolis - Santa Catarina, Brazil / Infecção genital pelo Papilomavírus Humano em mulheres de Florianópolis - Santa Catarina, Brasil

Introduction: Human Papillomavirus (HPV) infection is the most common sexually transmitted infection in women. About 80% of sexually active women will have contact with this virus at some age in their lives. Most infections will be transient, but when the infection becomes persistent, associated with high oncogenic risk HPV, there may be progression to cancer, especially cervical cancer. The best way to prevent HPV infection is through the use of vaccines. Objective: To assess which are the most prevalent types of HPV in the city of Florianópolis, Brazil and if the majority of the diagnosed types are contained in the HPV vaccines currently available on the market and in the public health sector. Methods: More than 14,727 HPV tests were evaluated for the diagnosis of genital HPV infection in women from Florianópolis. The prevalence of infection was evaluated according to age of the women. HPV detection was performed using molecular biology tests, such as hybrid capture (for diagnosis of the HPV group, high or low oncogenic risk) and PCR (viral genotyping) techniques. Results: The diagnosis of HPV infection was made for women between one and 102 years of age. The highest positivity of the exams was observed in women aged 20­25 years (51% of the exams). The most prevalent age group was 31­35 years old (23.5%), and the lowest was for women aged 70 and above (0.6%). High oncogenic risk HPV was detected in 94.1% of positive samples and was the most frequent in all age groups. Mixed infection (high- and low-risk HPV) was more prevalent in the 66­70 age group (25.6%). The most frequent genotypes were non-16/18 high oncogenic risk HPV (77% of positive cases). HPV 16 was found in 17.1% of positive cases, and HPV 18 in 6.5%. Conclusion: The most prevalent types of HPV in Florianópolis in the last 6 years are non-16/18 high oncogenic risk HPV types, viral types not covered by the current HPV vaccine available in the public health sector in Brazil.

Introdução: A infecção pelo Papilomavírus Humano (HPV)é a infecção sexualmente transmissível mais frequente na mulher. Cerca de 80% das mulheres sexualmente ativas irão entrar em contato com este vírus em algum momento da sua vida. A maioria das infecções será transitória, mas quando a infecção se torna persistente, associada aos HPV de alto risco oncogênico, poderá haver a progressão para o câncer, principalmente o câncer de colo de útero. A melhor forma de prevenção da contaminação pelo HPV é através da utilização das vacinas. Objetivo: Avaliar quais são os tipos de HPV mais prevalentes na cidade de Florianópolis, Brasil, e se a maioria dos tipos diagnosticados estão contidos nas vacinas contra o HPV atualmente disponíveis no mercado e no setor público de saúde. Métodos: Foram avaliados 14.727 exames para diagnóstico da infecção genital pelo HPV em mulheres de Florianópolis, de acordo com a idade das mulheres. A detecção do HPV foi realizada através dos exames de biologia molecular pelas técnicas de captura híbrida (para diagnóstico do grupo de HPV, alto ou baixo risco oncogênico) e PCR (genotipagem viral). Resultados: Foram avaliados exames para diagnóstico da infecção de mulheres entre um e 102 anos de idade. A maior positividade dos exames foi observada em mulheres dos 20­25 anos (51% dos exames). A faixa etária de maior prevalência foi dos 31­35 anos (23,5%), e a menor, após os 70 anos (0,6%). O HPV de alto risco oncogênico foi detectado em 94,1% dos casos positivos e foi o mais frequente em todas as faixas etárias. A infecção mista (HPV de alto e baixo risco) foi mais prevalente na faixa etária dos 66­70 anos (25,6%). Os genótipos mais frequentes foram os HPV de alto risco oncogênico não 16/18 (77% dos casos positivos). O HPV 16 foi encontrado em 17,1% dos casos positivos, e o HPV 18 em 6,5%. Conclusão: Os tipos de HPV mais prevalentes em Florianópolis nos últimos 6 anos são os HPV de alto risco oncogênico não 16/18, tipos virais não cobertos pela atual vacina contra o HPV disponível no setor público de saúde do Brasil.Palavras-chave: HPV. Tipos de HPV. Câncer de colo de útero. Cobertura vacinal.

Virus del papiloma humano en carcinoma colorrectal / Human papilloma virus in colorectal carcinoma

Resumen Introducción: Previos trabajos han reportado una asociación entre la infección del virus del papiloma humano (VPH) y el desarrollo de cáncer colorrectal, aunque existe controversia al respecto. Materiales y Método: Estudio observacional, transversal, descriptivo, retrospectivo, no ciego. Se utilizaron 50 muestras de patología con diagnóstico de adenocarcinoma colorrectal, incluidas en parafina, para aislar ADN de las muestras. Se realizó la extracción de ADN mediante protocolos establecidos para extracción, lisis y rehidratación de muestra. Se identificó y genotipicó el ADN del virus para amplificar y detectar subtipos oncogénicos de entre 35 subtipos diferentes incluidos en la prueba, secuenciando las muestras positivas, utilizando protocolos ya establecidos de purificación y análisis de muestra, mediante microarreglos. Resultados: Se identificaron 14 muestras de 50 (28%) estudiadas positivas para el virus de papiloma humano de las cuales 11 (22%) incluyen uno o más subtipos de alto riesgo para neoplasia. No se identificaron diferencias estadísticamente significativas entre grupos en cuanto a edad, sexo, localización del tumor, grado de diferenciación, infiltración, ganglios afectados, metástasis o número de paquetes/año. Conclusión: La detección de los subtipos de VPH de alto riesgo en un alto porcentaje de las muestras positivas, sugiere una asociación entre la infección con el desarrollo de cáncer colorrectal.

Introduction: Previous works have reported an association between human papilloma virus (HPV) infection and the development of colorectal cancer, and although controversy regarding this association exists. Materials and Method: This was an observational, cross-sectional, descriptive, retrospective unblinded study. Fifty pathology samples embedded in paraffin with a diagnosis of colorectal adenocarcinoma were used to isolate DNA from the tissue. DNA was extracted according to established protocols for extraction, lysis and sample rehydration. Viral DNA was identified and genotypified to amplify and detect oncogenic subtypes among 35 different subtypes included in the study, sequencing positive samples with established protocols of purification and sample analysis using microarrays. Results: Fourteen of 50 (28%) samples were identified as positive for human papilloma virus; of these 11 (22%) included one or more high-risk subtypes for neoplasia. Statistically significant differences were not found between the groups regarding age, sex, tumor location, degree of differentiation, infiltration, affected lymph nodes, metastasis and number of pack years. Conclusion: The detection of high-risk VPH subtypes in a high percentage of positive samples, suggests an association between infection and the development of colorectal cancer.

In vivo and ex vivo dermoscopy of lesions from implantation of human papillomavirus in tattoos: report of two cases

Abstract The number of individuals with tattoos has been increasing worldwide, alongside with reports of complications varying from reactions to the injected pigments to infections caused by agents inoculated in the pigmentation process. The diagnosis of such unwanted events can be obtained through complementary non-invasive methods, preserving the maximum of the tattoo design. The authors present two cases of patients with warts on tattooing, and correlate their clinical aspects to in vivo and ex vivo dermoscopy, and to the findings in the histopathological examination, aiming to determine patterns that aid the diagnosis of these lesions without performing biopsy.

Human papillomavirus infection in men with condyloma acuminatum: Genotype analysis of 70 cases / 中华男科学杂志

Objective@#To investigate the distribution of the gene subtypes of human papillomavirus (HPV) in male patients with condyloma acuminatum (CA) and analyze the characteristics of the gene subtypes.@*METHODS@#We extracted genomic DNA of the HPV virus from the genital tissue of 70 male CA patients, detected the DNA subtypes of HPV using the PCR-reverse dot hybridization technique, and analyzed the rates of different subtypes identified and their characteristics of distribution in different age groups.@*RESULTS@#The male HPV-positive patients were mainly infected at the age of 20－39 years, primarily with high- and low-risk mixed infection of various subtypes, which accounted for 61.54% in the 20- to 29-year-olds and 42.86% in the 30- to 39-year-olds. Among the 70 CA patients, 22 HPV subtypes were identified, the top five subtypes including HPV 11 (21.08%), HPV 6 (19.46%), HPV 42 (6.49%), HPV 59 (6.49%) and HPV 53 (5.95%); 20 infected with a single subtype (28.57%), 19 with two subtypes (27.14%) and 31 with three or more (44.29%); and 30 infected with a low-risk single subtype (42.86%) and 40 with both high- and low-risk multiple subtypes (57.14%).@*CONCLUSIONS@#Male patients with CA are mainly infected with HPV 11 and HPV 6, with a significantly higher rate of multi-subtype than single-subtype infection, and the multi-subtype patients chiefly with high- and low-risk mixed infection. Men aged 20－39 years old are most commonly affected by CA.

Molecular detection of oncogenic subtypes of human papillomavirus (HPV) in a group of women in the Amazon region of Brazil

The natural history of cervical cancer is strongly related to the presence of human papillomavirus (HPV) infection, with its relationship with cervical cancer being a matter of concern. It is estimated that 70% of all cervical cancers worldwide are caused by HPV 16 and 18. Accordingly, the present study aimed to contribute to the identification of HPV subtypes circulating in a group of women of Manaus-Brazil. Cervical samples were collected from 49 women, following the eligibility criteria of the study, and DNA was then extracted from the samples, which were analyzed for the presence of the virus in the genetic material through the polymerase chain reaction (PCR) using generic primers (GP05/06). Finally, identification of the viral subtypes was performed using specific primers for the detection of the main subtypes already examined (16 and 18). Positive HPV DNA was detected in 100% of the samples included in the study. Human papillomavirus 16 was the most prevalent subtype in the majority of lesions, accounting for 29 (59.2%) of the positive cases, and HPV 18 was detected in four (8.2%) women. In these 4 cases there was co-infection, with the presence of both HPV 18 and HPV 16. Therefore, 40.8% (20 cases) in which HPV DNA was detected presented infection with other subtypes of HPV not included in the study. This data has clinical implications related to cervical cancer prevention, as the current prophylactic HPV vaccines are only effective against high-risk HPV 16 and 18 subtypes.

Genotipificación de VPH en papilomas orales de pacientes con infección por VIH del Hospital San Juan de Dios / HPV genotypes in oral papilloma in Hospital San Juan de Dios HIV (+) patients

Resumen Introducción: Pacientes con infección por VIH presentan mayor riesgo de infecciones orales con genotipos de virus papiloma humano (VPH) de alto riesgo oncogénico (VPH-AR). Objetivo: Determinar los genotipos de VPH en lesiones papilomatosas orales de pacientes con infección por VIH y describir los factores clínicos, histopatológicos y recuento de linfocitos T CD4+ y carga viral asociados. Métodos: Se estudiaron ocho sujetos adultos con infección por VIH y lesiones papilomatosas por VPH. Se extrajo el ADN de la lesión y se detectó el genoma y los genotipos de VPH mediante reacción de polimerasa en cadena e hibridación con el kit comercial HPV 3.5 LCD-Array (Chipron®) y se describieron factores asociados. Resultados: El 63% de los pacientes exhibió más de un genotipo de VPH y 75% de ellos exhibió al menos un genotipo VPH-AR. El genotipo más frecuente fue el VPH 52 (27%), seguido del VPH16 y 56 (18%). El recuento medio de linfocitos T CD4+ en pacientes con al menos un genotipo VPH-AR fue de 330,6 céls/mm3. Conclusiones: Se detectó una mayor frecuencia de infecciones múltiples por VPH, incluido al menos un genotipo de alto riesgo. El genotipo VPH-AR 52 fue el más frecuente. El recuento medio de LT CD4+ en pacientes que presentan al menos un genotipo VPH-AR indica una inmunosupresión moderada. Se requiere aumentar el número de pacientes.

Background: HIV (+) patients have a higher risk of oral infections with high oncogenic risk HPV (HPV-HR). Aim: To determine the HPV genotypes in oral papillomatous lesions in HIV (+) patients and describe the associated factors. Methods: Eight adults HIV (+) subjects with papillomatous HPV lesions were studied. The lesions DNA was extracted and HPV genome and genotypes were detected by PCR and the commercial kit HPV 3.5 LCD-Array Kit (Chipron®) and associated factors were described. Results: 63% of patients exhibited more than one HPV genotype and 75% of them exhibited at least 1 HPV-HR genotype. The most frequent genotype was HPV 52 (27%), followed by HPV 16 and 56 (18%). The mean CD4 T lymphocyte count in patients with at least one HPV-HR genotype was 330.6 cells/mm3. Conclusions: A higher frequency of multiple HPV infections was detected, including at least one high-risk genotype. The genotype HPV-AR 52 was the most frequent. The mean CD4 T lymphocyte count in patients with at least one HPV-HR genotype indicates moderate immunosuppression. It is required to increase the number of patients.

Detección y tipificación del Virus Papiloma Humano en el marco del tamizaje virológico para la detección de lesiones del cuello uterino en Asunción, Paraguay / Detection and typing of Human Papilloma Virus during a virological screening for detection of cervical lesions in Asunción, Paraguay

En Paraguay la incidencia de cáncer de cuello uterino (CCU) es superior a las observadas en otros países de la región. El agente etiológico asociado al CCU es el virus papiloma humano (VPH), esencialmente tipos de alto riesgo oncogénicos. El objetivo es describir aspectos epidemiológicos de la infección genital por el virus papiloma humano de alto riesgo (VPH-AR) en mujeres de 25 a 64 años que consultaron en servicios de Patología Cervical del MSPyBS, de mayo a diciembre de 2013. Se utilizó el Cobas 4800 HPV Test (Roche) que permite la detección individual de VPH-16 y VPH-18 y un pool de otros VPH-AR que incluye 12 genotipos de alto riesgo. Los otros VPH-AR fueron tipificados por hibridación reversa en línea (RLB). Entre las 495 mujeres incluidas, se detectaron 72 casos positivos (14,5%) de VPH-AR. Se identificaron 19 tipos virales; siendo el más frecuente VPH-16 (2,1%), seguido del VPH-31, 33, 58 y 66; el VPH-18 aparece en sexto lugar. Este trabajo aporta los primeros datos sobre la implementación de técnicas moleculares para detección y tipificación de VPH como parte del sistema de salud pública de Paraguay. El predominio de VPH-16, confirma su amplia circulación a nivel mundial y dado su mayor potencial oncogénico, representa una alerta a considerar, en especial en las mujeres mayores de 30 años portadoras de una infección persistente. Estos resultados apoyan la importancia de la implementación criteriosa y la utilización apropiada de las pruebas moleculares actualmente disponibles para la prevención y control del CCU(AU)

Can quadrivalent human papillomavirus prophylactic vaccine be an effective alternative for the therapeutic management of genital warts? an exploratory study

ABSTRACT Objective: To evaluate the treatment effect of genital warts, we investigated the quadrivalent HPV vaccine injection compared with surgical excision. Materials and Methods: This prospective study included 26 patients (M:F = 24:2) who received HPV vaccine or surgical excision. After explanation of surgical excision or HPV vaccine, 16 patients underwent surgical excision and the others received HPV vaccine injections. Based on gross findings of genital warts, treatment outcomes were classified as complete response (no wart), partial response, and failed treatment. Results: Among enrolled patients, 42% (11 / 26) patients had recurrent genital warts. In vaccination group, complete response rates of genital wart were 60% following 3 times HPV vaccine. Partial response patients wanted to excise the genital lesions before the 3 times injection, because they worried about sexual transmission of disease to their sexual partners. One patient underwent surgical excision after 3 times injection. Excision sites included suprapubic lesions, but other sites including mid-urethra and glans showed complete response after injection. At a mean follow-up period of 8.42 ± 3.27 months, 10 patients (100%) who received HPV vaccine did not show recurrence. Conclusion: The response rates after HPV vaccine injection were 90% (complete and partial). Our results suggested that HPV vaccines could be effective in management of genital warts.

Importancia del sistema de Bethesda en el diagnóstico citológico de lesiones precancerosas del cérvix / The importance of Bethesda system in the cytological diagnosis of the cervix pre-cancerous lesions

RESUMEN El cáncer cérvico uterino, causa alrededor de 250 000 muertes anuales en el mundo y alrededor de 400 en Cuba, a pesar del esfuerzo que realiza el MINSAP, a través del Programa de Pesquisaje. Con el mismo se puede obtener el diagnóstico de lesiones precursoras del cáncer de cuello uterino, este diagnóstico citológico se realiza en Cuba a través del método de Richard y Barron que demuestra que existe un progreso citológico aparente hasta llegar al cáncer, que comienza con neoplasia intraepitelial (NICI a NICIII y carcinoma in situ), hasta finalmente el cáncer invasor. Por otro lado existe el método de Bethesda que responde casi todas las interrogantes que la citología plantea para su enfrentamiento, evidentemente los mayores aportes y revisiones se enfocan al manejo de las citologías atípicas de significado incierto, ya que no sólo presentan un mayor número de posibles evaluaciones, sino que representan el mayor porcentaje de citologías alteradas y la inclusión del VPH en las lesiones de bajo grado. En Cuba todavía se clasifica por el método de Richard y no se utiliza el Bethesda. Por la alta incidencia de esta entidad el propósito de este trabajo es emitir consideraciones sobre la implementación del sistema de Bethesda en el diagnóstico citológico de lesiones precancerosas del cérvix.

ABSTRACT The cervical-uterine cancer causes almost 250 000 death a year around the world and around 400 in Cuba in spite of the efforts made by the Public Health Ministry through the Screening Program. With it, the diagnosis of lesions that are predecessors of the cervical cancer could be reached. This cytological diagnosis is carried out through the Richard and Barron method, showing that there is an apparent cytological progress leading to the cancer that begins with intraepithelial neoplasia (NICI and NICIII and carcinoma in-situ) and ends in the invasive cancer. From the other hand there is the Bethesda methods answering to all the questions cytology ask for confronting it. Obviously the biggest contributions and reviews are focused in the management of the atypical cytologies with uncertain significance since they not only have a higher number of possible evaluations, but also represent the highest percent of the altered cytologies and the inclusion of the HPV in low grade lesions. The classification in Cuba is still made by the Richard method and the Bethesda one is not used. Due to the high incidence of this entity, the aim of this article is exposing considerations on the implementation of the Bethesda system in the cytological diagnosis of cervix pre-cancerous lesions.

Optimización de una técnica de PCR convencional para detección de virus de papiloma humano tipo 16 y 18 / Optimization of a conventional PCR technique for detection of human papillomavirus type 16 and 18

El cáncer de cuello uterino es el segundo cáncer femenino más común a nivel mundial. El agente causal es el virus de papiloma humano (VPH). Se han identificado 13 tipos de virus de papiloma humano de alto riesgo oncogénico (VPH-AR), entre los cuales el VPH 16 y VPH 18 son los más frecuentemente detectados en cáncer de cuello uterino, siendo en Paraguay detectados en el 70% de casos de cáncer invasor. Por ello, el objetivo fue estandarizar y determinar el límite de detección de una técnica de PCR convencional para la detección de VPH 16 y 18. Para la detección de ADN de VPH 16 y 18, se observaron mejores resultados con 2mM de MgCl2 y 60°C para la temperatura de alineamiento. El límite de detección para las PCR fue de 14,6x10-11ng/µL para VPH 16 y 21,7x10-12ng/µL para VPH 18. Este trabajo servirá de base a otros estudios de detección e identificación de estos tipos virales por PCR, con miras a identificar un grupo de mujeres positivas para VPH-AR que poseen mayor riesgo de desarrollo de lesión y cáncer de cuello uterino y precisan de un seguimiento más cercano(AU

Cervical cancer is the second most common female cancer worldwide. It is caused by the human papilloma virus (HPV). Thirteen genotypes of high oncogenic risk human papilloma viruses (HPV-HR) have been identified, among which types 16 and 18 are the most frequently detected in cervical cancer. In Paraguay, they are detected in 70% of the invasive cancer cases. Therefore, the objective was to standardize and determine the detection limit of a conventional PCR technique for the detection of HPV 16 and 18. Better results were observed with 2mM MgCl2 and 60°C for the alignment temperature in detection of HPV 16 and 18 DNA. The limit of detection was 14.6x10-11ng/µL for HPV 16 and 21.7x10-12ng/µL for HPV 18. This work will help other studies for the detection and identification of these viral types by PCR in order to identify a group of HPV-HR positive women who have higher risk for the development of lesions and cervical cancer and need a closer follow-up(AU)

Detección del virus del papiloma humano en muestras obtenidas mediante técnica de autotoma en un grupo de universitarias peruanas / Detection of the human papillomavirus in samples obtained by self-collection technique in a group of peruvian college students

RESUMEN Estudio transversal que determinó la frecuencia y genotipos del virus del papiloma humano de alto riesgo (VPH-AR) a través de la técnica de autotoma en un grupo de universitarias de Lima. Participaron 221 estudiantes y se detectó el ADN del VPH-AR con el método de reacción en cadena de la polimerasa (PCR). La frecuencia del VPH-AR en las participantes fue de 43,4%; de este grupo se encontraron los genotipos VPH 16 en el 15,6% y VPH 18 en el 4,2% y otros VPH-AR en el 80,2%. Se concluye que la frecuencia del VPH-AR es mayor en el grupo de universitarias de este estudio en comparación a investigaciones nacionales previas.

ABSTRACT Cross-sectional study that determined the frequency and the genotypes of the (HR-HPV) high-risk human papillomavirus through the self-collection technique in a group of college students of Lima. Two hundred twenty-one (221) students participated and the DNA of the HR-HPV was detected with polymerase chain reaction (PCR). The frequency of HR-HPV in participants was 43.4%; of this group, genotype HPV 16 was present in 15.6%, HPV 18 in 4.2%, and another HR-HPV in 80.2%. We can conclude that the frequency of HR-HPV is greater in the group of college students of this study in comparison with previous national investigations.

A high prevalence of human papillomavirus 16 and 18 co-infections in cervical biopsies from southern Brazil

ABSTRACT HPV types 16 and 18 were studied in paraffin-fixed cervical biopsy collected in southern Brazil. HPV 16, HPV 18 and co-infection HPV 16/18 were identified in 10/57 (17.5%), 4/57 (7%) and in 43/57 (75.4%) samples, respectively. Southern Brazil has one of the highest prevalence rates of HPV 16/18 reported.

PCR-RFLP assay as an option for primary HPV test

Persistent human papillomavirus (HPV) infection is an essential factor of cervical cancer. This study evaluated the analytical performance of restriction fragment length polymorphism polymerase chain reaction (PCR-RFLP) assay compared to PapilloCheck® microarray to identify human papilloma virus (HPV) in cervical cells. Three hundred and twenty-five women were analyzed. One sample was used for conventional cytology and another sample was collected using BD SurePath™ kit for HPV tests. Eighty samples (24.6%) were positive for HPV gene by PCR-Multiplex and were then submitted to PCR-RFLP and PapilloCheck® microarray. There was a genotyping agreement in 71.25% (57/80) on at least one HPV type between PCR-RFLP and PapilloCheck® microarray. In 22 samples (27.5%), the results were discordant and those samples were additionally analyzed by DNA sequencing. HPV 16 was the most prevalent HPV type found in both methods, followed by HPVs 53, 68, 18, 39, and 66 using PCR-RFLP analysis, and HPVs 39, 53, 68, 56, 31, and 66 using PapilloCheck® microarray. In the present study, a perfect agreement using Cohen's kappa (κ) was found in HPV 33 and 58 (κ=1), very good for HPV 51, and good for types 16, 18, 53, 59, 66, 68, 70, and 73. PCR-RFLP analysis identified only 25% (20/80) HPV coinfection, and PapilloCheck® microarray found 62.5% (50/80). Our Cohen's kappa results indicate that our in-house HPV genotyping testing (PCR-RFLP analysis) could be applied as a primary HPV test screening, especially in low income countries. If multiple HPV types are found in this primary test, a more descriptive test, such as PapilloCheck® microarray, could be performed.

Regulation of HPV transcription

Human papillomavirus infection is associated with the development of malignant and benign neoplasms. Approximately 40 viral types can infect the anogenital mucosa and are categorized into high- and low-risk oncogenic human papillomavirus, depending on their association with the development of cervical carcinoma. High-risk human papillomavirus 16 and 18 are detected in 55% and 15% of all invasive cervical squamous cell carcinomas worldwide, respectively. Low-risk human papillomavirus 6 and 11 are responsible for 90% of genital warts and are also associated with the development of recurrent respiratory papillomatosis. Human papillomavirus preferentially infects mitotic active cells of the basal layer from both mucosal and cutaneous epithelium through microabrasions. The viral life cycle synchronizes with the epithelial differentiation program, which may be due, in part, to the binding of differentially expressed cellular transcription factors to the long control region throughout the various epithelial layers. This review aimed to summarize the current knowledge regarding the mechanisms by which viral gene expression is regulated and the influence of human papillomavirus heterogeneity upon this phenomenon. A better understanding of the regulatory mechanisms may elucidate the particularities of human papillomavirus-associated pathogenesis and may provide new tools for antiviral therapy.

Innate immunity and HPV: friends or foes

Most human papillomavirus infections are readily cleared by the host immune response. However, in some individuals, human papillomavirus can establish a persistent infection. The persistence of high-risk human papillomavirus infection is the major risk factor for cervical cancer development. These viruses have developed mechanisms to evade the host immune system, which is an important step in persistence and, ultimately, in tumor development. Several cell types, receptors, transcription factors and inflammatory mediators involved in the antiviral immune response are viral targets and contribute to tumorigenesis. These targets include antigen-presenting cells, macrophages, natural killer cells, Toll-like receptors, nuclear factor kappa B and several cytokines and chemokines, such as interleukins, interferon and tumor necrosis factor. In the present review, we address both the main innate immune response mechanisms involved in HPV infection clearance and the viral strategies that promote viral persistence and may contribute to cancer development. Finally, we discuss the possibility of exploiting this knowledge to develop effective therapeutic strategies.

A pilot study on the identification of human papillomavirus genotypes in tongue cancer samples from a single institution in Ecuador

The relationship between human papillomavirus (HPV) and oropharyngeal squamous cell carcinoma has been established. However, data from Ecuador is limited. The objective of this study was to characterize HPV infection in Ecuadorian patients with tongue cancer. Fifty-three patients with tongue cancer treated at the tertiary referral center Sociedad de Lucha Contra el Cancer (SOLCA), Guayaquil, between 2006 and 2011 were identified. Linear Array® HPV genotyping was used to identify the presence and types of HPV on formalin-fixed paraffin-embedded biopsy samples from these patients with tongue cancer. HPV was identified in 42% (n=22) and high-risk (HR) HPV in 17% (n=9), with 18 different HPV types identified. The most common types were the HR HPV 33 (14%) and low-risk HPV 67 (14%), followed by the HR HPV 58. More than one HPV type was identified in 27.3% of cases. HPV 33 was frequently associated with other HPV types. No statistically significant differences in gender (P=0.58) and age (P=0.12) were observed between HPV-positive and HPV-negative cases. HPV was identified in almost half of the tongue cancer samples, with subtypes 33 and 67 being the most common. This suggested that HPV played an important role in this disease in the population studied. Given these results, current HPV vaccines may not be as effective in reducing tongue cancer rates in this population.

Human papillomavirus and genome instability: from productive infection to cancer

Infection with high oncogenic risk human papillomavirus types is the etiological factor of cervical cancer and a major cause of other epithelial malignancies, including vulvar, vaginal, anal, penile and head and neck carcinomas. These agents affect epithelial homeostasis through the expression of specific proteins that deregulate important cellular signaling pathways to achieve efficient viral replication. Among the major targets of viral proteins are components of the DNA damage detection and repair machinery. The activation of many of these cellular factors is critical to process viral genome replication intermediates and, consequently, to sustain faithful viral progeny production. In addition to the important role of cellular DNA repair machinery in the infective human papillomavirus cycle, alterations in the expression and activity of many of its components are observed in human papillomavirus-related tumors. Several studies from different laboratories have reported the impact of the expression of human papillomavirus oncogenes, mainly E6 and E7, on proteins in almost all the main cellular DNA repair mechanisms. This has direct consequences on cellular transformation since it causes the accumulation of point mutations, insertions and deletions of short nucleotide stretches, as well as numerical and structural chromosomal alterations characteristic of tumor cells. On the other hand, it is clear that human papillomavirus-transformed cells depend on the preservation of a basal cellular DNA repair activity level to maintain tumor cell viability. In this review, we summarize the data concerning the effect of human papillomavirus infection on DNA repair mechanisms. In addition, we discuss the potential of exploiting human papillomavirus-transformed cell dependency on DNA repair pathways as effective antitumoral therapies.

Alterations in the expression and activity of extracellular matrix components in HPV-associated infections and diseases

Infection with human papillomaviruses is associated with a series of benign and malignant hyperproliferative diseases that impose a heavy burden on human populations. A subgroup of mucosal human papillomavirus types are associated with the majority of cervical cancers and a relevant fraction of vulvar, vaginal, anal, penile and head and neck carcinomas. Human papillomaviruses mediate cell transformation by the expression of two pleiotropic oncoproteins that alter major cellular regulatory pathways. However, these viruses are not complete carcinogens, and further alterations within the infected cells and in their microenvironment are necessary for tumor establishment and progression. Alterations in components of the extracellular matrix for instance, matrix metalloproteinases and some of their regulators such as tissue inhibitors of metalloproteinases, have been consistently reported in human papillomaviruses-associated diseases. Matrix metalloproteinases function by remodeling the extracellular matrix and alterations in their expression levels and/or activity are associated with pathological processes and clinical variables including local tumor invasion, metastasis, tumor relapse and overall patient prognosis and survival. In this review we present a summarized discussion on the current data concerning the impact of human papillomavirus infection on the activity and expression of extracellular matrix components. We further comment on the possibility of targeting extracellular matrix molecules in experimental treatment protocols.

Characterisation of complete high- and low-risk human papillomavirus genomes isolated from cervical specimens in southern Brazil

The classification of human papillomavirus (HPV) intratypic lineages by complete genome sequencing is a determinant in understanding biological differences in association with this disease. In this work, we have characterised complete HPV genomes from southern Brazil. Fifteen cervicovaginal Pap smear negative samples previously categorised as HPV-positive were sequenced using ultradeep sequencing, and 18 complete genomes from 13 different HPV types were assembled. Phylogenetic and genetic distance analyses were performed to classify the HPV genomes into lineages and sublineages. This is the first report describing the distribution of HPV intratype lineages of high and low oncogenic risk in asymptomatic women from southern Brazil.

Human papillomavirus type distribution and HPV16 intratype diversity in southern Brazil in women with and without cervical lesions

BACKGROUND Increasing evidence suggests that human papillomavirus (HPV) intratype variants (specific lineages and sublineages) are associated with pathogenesis and progression from HPV infection to persistence and the development of cervical cancer. OBJECTIVES This study aimed to verify the prevalence of HPV infection and distribution of HPV types and HPV16 variants in southern Brazil in women with normal cytology or intraepithelial lesions. METHODS HPV typing was determined by L1 gene sequencing. To identify HPV16 variants, the LCR and E6 regions were sequenced, and characteristic single nucleotide variants were identified. FINDINGS A total of 445 samples were studied, with 355 from cervical scrapes and 90 from cervical biopsies. HPV was detected in 24% and 91% of these samples, respectively. The most prevalent HPV types observed were 16 (cervical, 24%; biopsies, 57%) and 58 (cervical, 12%; biopsies, 12%). Seventy-five percent of the HPV16-positive samples were classified into lineages, with 88% defined as lineage A, 10% as lineage D, and 2% as lineage B. MAIN CONCLUSIONS This study identified a high frequency of European and North American HPV16 lineages, consistent with the genetic background of the human population in southern Brazil.