Análise crítica dos métodos moleculares para detecção do papilomavírus humano: revisão da literatura / Molecular methods for human papillomavirus detection: literature review

O papilomavírus humano (HPV) é um vírus que infecta o epitélio cutâneo e das mucosas. Células infectadas por este vírus perdem a capacidade de controlar o ciclo celular e passam a proliferar descontroladamente gerando alterações displásicas que podem progredir para lesões malignas. Existem mais de 200 tipos de HPV e entre eles aqueles que apresentam maior ou menor risco de causar câncer. Dessa forma, o HPV pode ser classificado como sendo de baixo risco ou alto risco. Os métodos mais utilizados em pesquisa para análise molecular do HPV é a hibridização in situ (ISH), reação em cadeia da polimerase (PCR) que varia desde a PCR alelo específica, passando pelo tipo Nested e a PCR multiplex, e a mais nova técnica baseada na tecnologia de microarray. A maioria destes testes é realizada apenas em centros de pesquisa, e não rotineiramente na clínica. Por outro lado, o teste de captura híbrida II para HPV, baseado na hibridização do DNA, é comercialmente disponível. As técnicas para detecção do DNA do HPV e sua genotipagem variam quanto a sua sensibilidade e especificidade. Técnicas que utilizam sondas como a hibridização in situ e o Southern blotting são as menos sensíveis para detecção da sequência do DNA, enquanto que as mais sensíveis são as técnicas que utilizam a amplificação do DNA alvo, como a PCR e a qPCR. À medida que a tecnologia avança, as técnicas moleculares vão se aprimorando para a detecção do HPV. O objetivo final é desenvolver uma metodologia de baixo custo que apresente resultados rápidos e eficientes.

The human papillomavirus (HPV) is a virus that infects the skin and mucosal epithelium. Infected cells lost the ability to control cell cycle and begin to proliferate uncontrollably causing dysplastic alterations that can progress to malignant lesions. There are over 200 types of HPV with higher or lower risk of causing cancer. Thereby, HPV can be classified as high risk or low risk. The methods used in research for molecular analysis of HPV is the in situ hybridization (ISH), polymerase chain reaction (PCR) that varies from the allele specific PCR, Nested, PCR multiplex, and the newest technique based on microarray technology. Most of these tests are performed only in research centers, and not routinely in the clinic. An exception is the Hybrid Capture II test for HPV. The detection techniques of HPV and its genotyping vary in their sensitivity and specificity. Techniques that use probes, as in situ hybridization and Southern blotting are less sensitive for detection of DNA sequence, while the most accurate are the techniques based on DNA amplification, such as PCR and qPCR. As technology advances, molecular techniques become more accurate for the detection of HPV. The ultimate goal is to develop an inexpensive method to provide rapid and efficient results.

HPV infection in Brazilian patients with esophageal squamous cell carcinoma: interpopulational differences, lack of correlation with surrogate markers and clinicopathological parameters.

The role of HPV in esophageal squamous cell carcinoma (ESCCs) is controversial. Therefore, we determined, through different methodologies, the prevalence of HPV in 264 ESCC samples from Brazil, and correlated it with the presence of surrogate markers and clinicopathological characteristics. HPV is present in 13% of ESCC, and with a 3-fold variation between high and medium incidence areas. Most HPV positive tumors were infected with HPV16, but this was not associated with p16 expression, TP53 mutation status, patient age, amount of tobacco or alcohol consumption, or overall survival. We conclude that HPV infection may not have a role in ESCC.

Infecção oral pelo HPV e lesões epiteliais proliferativas associadas / HPV oral infection and proliferative epithelial associated lesions

Os papilomavírus humanos (HPVs) pertencem à família Papillomaviridae e seu ciclo de vida é diretamente ligado à diferenciação das células epiteliais do hospedeiro. Possuem seis genes que se expressam precocemente e dois genes que se expressam tardiamente, sendo denominados respectivamente E (early) e L (late). O ácido desoxirribonucleico (DNA) viral dentro da célula do hospedeiro pode assumir duas formas: epissomal e integrada. O HPV tem como alvo as células basais de epitélios escamosos, em particular da área genital, onde está associado ao carcinoma da cérvice uterina. Na boca, o HPV está associado a papiloma escamoso oral, condiloma acuminado, verruga vulgar e hiperplasia epitelial focal. Entretanto, seu papel na carcinogênese oral é ainda controverso, sendo também identificado como agente etiológico de alguns carcinomas de células escamosas de cabeça e pescoço. A infecção pelo HPV pode agir sinergicamente com agentes carcinogênicos, como o tabaco e o álcool. Pelo menos 150 subtipos diferentes de HPV já foram identificados, sendo que 25 têm sido detectados em lesões orais. Considerando a relevância do tema para a melhor compreensão da infecção oral pelo HPV, o objetivo desta atualização é rever os aspectos relevantes da biologia do HPV, com ênfase na relação HPV-ceratinócitos, e a importância dos dados clínicos e histopatológicos na definição diagnóstica das lesões orais possivelmente associadas ao HPV.

Papillomaviruses belong to the family Papillomaviridae and their life cycle is directly linked to the differentiation of host epithelial cells. They have six genes that are expressed earlier and two genes that are expressed later in their life cycle, named respectively E (early) and L (late). Host cell viral DNA can take two forms: episomal and integrated. The human papillomavirus (HPV) targets the basal cells of squamous epithelia, particularly from the genital area, which is associated with uterine cervix carcinoma. In the oral area HPV is associated with oral squamous papilloma, condyloma acuminatum, verruca vulgaris, and focal epithelial hyperplasia. However, its role in oral carcinogenesis is still controversial. Moreover, it has identified as an etiological agent of some head and neck squamous cell carcinomas. HPV infection may act synergistically with carcinogens such as tobacco and alcohol. At least 150 different subtypes of HPV have been identified, of which 25 types have been detected in oral lesions. Considering the relevance of the topic for better understanding of HPV oral infection, the objective of this update is to review relevant aspects of HPV biology, with emphasis on HPV-keratinocytes relationship and the importance of clinical and histopathological aspects in the diagnosis of oral lesions possibly associated with HPV.

Detection of Dialister pneumosintes in the subgingival biofilm of subjects with periodontal disease.

Dialister pneumosintes has been indicated as a potentially new periodontopathic species. This study evaluated the prevalence of this microorganism in saliva and subgingival biofilm from subjects with different periodontal conditions. Subgingival biofilm and saliva samples from 48 subjects with periodontal health (PH) and 116 patients with chronic periodontitis (CP) were obtained. DNA was extracted from the samples and the presence of D. pneumosintes was determined by PCR. Differences in clinical parameters and frequency of D. pneumosintes between groups were sought by Mann-Whitney, Chi-square and Fisher's exact tests. Overall, D. pneumosintes was detected in 47.8% of the biofilm samples, but only in 3% of saliva samples. CP patients presented a significantly greater mean prevalence of this species in sites with periodontal health and periodontal infection (43.5+/-7.4% and 62.1+/-6.4%, respectively) than PH subjects (29.4+/-7.9%) (Mann-Whitney; p<0.01). Moreover, significant associations between the prevalence of D. pneumosintes and pocket depth (p=0.001), attachment loss (p=0.001) and bleeding on probing (GLM, p=0.014) were observed after adjusting for age and gender. These findings corroborate the association of D. pneumosintes with periodontitis.