Papillomaviruses: their possible role in oral disease

Statistical analysis of human papillomavirus in a subset of upper aerodigestive tract tumors

Human papilloma virus (HPV) has been detected in some upper aerodigestive tract tumors, but the correlation between HPV and these tumors is not well understood. There is also some controversy regarding this correlation because a large variation in the prevalence of HPV in these tumors has been reported. To discuss the impact of HPV infection on upper aerodigestive tract tumors, this review estimated systematically the prevalence and risk of HPV in upper aerodigestive tract tumors from studies published between 1982 and 2012. In total, 418 articles were selected, which included 273 studies on the head and neck and 145 studies on esophageal squamous cell carcinoma. The overall prevalence of HPV in the 5,467 head and neck squamous cell carcinoma specimens was 36.3%. HPV was detected more frequently in the Americas (40%), than in Asia (38.6%), Europe (32%), or others regions (30.5%). The prevalence of HPV was significantly higher in oropharyngeal (48.5%) than in oral (32.5%), laryngeal (30.7%), and unselected head and neck squamous cell carcinoma (33.3%) (P < 0.001). The pooled prevalence of HPV in the 6,912 esophageal squamous cell carcinoma cases was 38.9% and it was significantly higher in China (44%) versus other regions (31.3%) (P < 0.05). Meta-analysis showed that head and neck and esophageal squamous cell carcinoma are associated with HPV infection (combined OR: 3.58, OR for head and neck and esophageal squamous cell carcinoma: 4.20). These findings suggest that HPV might be linked etiologically to the development of some upper aerodigestive tract tumors.

An update on oral human papillomavirus infection

Human papillomavirus (HPV) constitutes the majority of newly acquired sexually transmitted infections (STIs) in United States as per the centers for disease control factsheet 2013. Genital HPV is the most common STI with incidence of about 5.5 million world-wide, nearly 75% of sexually active men and women have been exposed to HPV at some point in their lives. Oral Sexual behavior is an important contributor to infection of HPV in the oral mucosa especially in cases known to practice high risk behavior and initiating the same at an early age. HPV infection of the oral mucosa currents is believed to affect 1-50% of the general population, depending on the method used for diagnosis. The immune system clears most HPV naturally within 2 years (about 90%), but the ones that persist can cause serious diseases. HPV is an essential carcinogen being implicated increasingly in association with cancers occurring at numerous sites in the body. Though there does not occur any specific treatment for the HPV infection, the diseases it causes are treatable such as genital warts, cervical and other cancers.

Human papillomavirus and oral disease - emerging evidence: a review

Human papillomavirus (HPV) infections have received considerable attention in recent years. Of the 120 or so known types of the virus, some cause a variety of benign wart-like lesions of the skin and genital and oral mucosae, whilst others are aetiologically associated with cervical and anogenital cancers. Recent epidemiologic evidence suggests that HPV may also be an independent risk factor for oropharyngeal cancer. In this context it has been suggested that HPV virus may modulate the process of carcinogenesis in some tobacco and alcohol induced oropharyngeal cancers and act as the primary oncogenic agent for inducing carcinogenesis among non-smokers. Dental practitioners have a major role in detecting all lesions of the oral mucosa caused, or possibly caused, by HPV. This paper briefly reviews the current state of knowledge of molecular and clinical aspects of HPV infections of the oral mucosa.

A review of risk factors for oral cavity cancer: the importance of a standardized case definition

The aim of this work is to review the literature on risk factors of oral cavity cancer with a special attention to the definition of the cases, in order to highlight special features of these cancers and of their subsites. PubMed database was systematically searched to access relevant articles published between 1980 and 2010. Reference lists of selected papers were examined to identify further articles. One hundred and two studies met the inclusion criteria. Their results were difficult to compare because of the lack of uniformity in defining oral cavity. In addition, few studies examined risk factors other than alcohol and tobacco, and studies differentiating between subsites were rare. Despite these limitations, some characteristics of oral cavity cancers may be emphasized: smoked tobacco seems to be a stronger risk factor for oral cavity cancer than alcohol, and the floor of the mouth seems to be more sensitive to the harmful effects of alcohol and smoked tobacco. Studies limited strictly to oral cavity cancers and distinguishing between subsites are needed to better understand the aetiology of these cancers, and better define risk groups to target prevention efforts and screening.

Prevalência do papilomavírus humano (HPV) na cavidade oral e na orofaringe

A prevalência do papilomavírus humano (HPV) na cavidade oral e na orofaringe ainda não está bem esclarecida como nos estudos do trato genital, na qual é bem definida. Entretanto, novas pesquisas estão surgindo após o aparecimento dos exames de biologia molecular. Neste estudo foi realizada uma revisão da literatura com o objetivo de verificar a prevalência do papilomavírus humano na cavidade oral e na orofaringe. Os resultados desta pesquisa mostraram uma prevalência do HPV 16 na mucosa oral normal (infecção latente). Já nas lesões benignas orais associadas ao HPV mostraram uma prevalência do HPV 6 e 11 em papilomas de células escamosas e condilomas, e, nas verrugas, uma prevalência do HPV 2 e 57, enquanto na hiperplasia epitelial focal prevaleceram os HPVs 13 e 32, e no câncer oral, principalmente, no carcinoma de células escamosas (CCE), foi evidenciada uma alta prevalência do HPV 16, o que sugere sua participação na carcinogênese oral, apesar de ser um assunto controverso. Constatou-se também uma enorme discrepância nos resultados da prevalência do papilomavírus humano (HPV) na mucosa oral normal (infecção latente) e no câncer oral, enquanto nas lesões benignas associadas ao vírus, os resultados foram confirmatórios.

Prevalence of human papillomavirus (HPV) in oral cavity and oropharynx

The prevalence of human papillomavirus (HPV) in the oral cavity and oropharynx has not yet been as well studied as its infection of the vaginal tract. However, new study are emerge after the development of molecular biology techniques. The objective of this study is to show the prevalence of HPV in the oral cavity and the oropharynx. An ample bibliographic review was done showing a prevalence of HPV 6, 11 in a normal oral mucous membrane (latent infection). In oral benign lesions associated with HPV, a prevalence of HPV 6 and 11 was observed in squamous cell papilloma (SCP) and condylomas acuminatum, while HPV 2 and 57 were more prevalent in verruca vulgaris lesions. As for focal epithelial hyperplasia (FEH) and oral cancer, especially squamous cell carcinoma (SCC), the prevalence was of HPV 13 and 32, and HPV 16, respectively. The last findings are, nonetheless, controversial. The last findings are, nonetheless, controversial. Showed also discrepancy result the prevalence of human papillomavírus (HPV) in normal oral mucous (latent infection) and in oral cancer, however evidenced confirmatory result in oral benign lesions associated with virus.

Oral cancer; the evidence for sexual transmission

The incidence of oral cancer amongst young adults is increasing in many European and high incidence countries. Most oral cancer is aetiologically linked to the use of tobacco and/or alcohol but nearly two decades ago, we produced the first evidence for the presence of viral nucleic acids in oral squamous cell carcinoma (OSCC) tissues, hypothesising that there may be a viral involvement in at least some OSCC. Subsequently, human papillomaviruses (HPV) in particular have been implicated in OSCC. Antibody responses to HPV are seen and HPV-DNA detected in tumours by us and many others, the virus being mainly HPV-16, the genotype associated with ano-genital cancer. Recent studies have indicated that HPV may be aetiologically important particularly in some types of oropharyngeal cancer, at least in tonsillar carcinogenesis, and may represent an alternative pathway in carcinogenesis to the established factors of tobacco and alcohol. Studies of patients with OSCC have suggested possible sexual transmission of HPV.

Detection of human papillomaviruses of high oncogenic potential in oral squamous cell carcinoma in a Venezuelan population

OBJECTIVE

The aim of this work was to detect and typify human papillomaviruses (HPV) in oral squamous cell carcinoma (OSCC) in a Venezuelan population. MATERIAL(S) AND METHODS: Eighteen tissue samples were obtained from biopsies, formalin-fixed, and paraffin-embedded; 16 were diagnosed as SCC. We isolated DNA from paraffin-embedded tissue; two to three sections of 5 microm were obtained and resuspended in digestion buffer and proteinase K. Five microliters of the aqueous phase was used for polymerase chain reaction (PCR). The PCR for HPV amplification was carried out with consensus primers for L1 region (MY09 and MY11) and beta-globin gene was used as internal control. The viral types were determined by molecular hybridization with a mix of probes for high/intermediate and low HPV oncogenic risk types.

RESULTS

The HPV-DNA was detected in 50% (eight of 16) of the SCC cases. Of these HPV-DNA-positive samples, 68% were histopathologically diagnosed as moderately differentiated SCC. The most common anatomical location was the alveolar ridge mucosa. All positive biopsies contained high oncogenic HPV types.

CONCLUSIONS

We observed a high prevalence of HPV infection of high oncogenic potential types in patients with SCC in our studied group. The moderately differentiated SCCs were more associated to HPV infection. These differences could be influenced by nutritional, environmental and genetical factors in our population but further studies should be carried out to determine these aspects.

HPV e carcinogênese oral: revisão bibliográfica

O Papilomavírus humano (HPV) é um vírus ubíquo de DNA, epiteliotrópico, que tem a pele e as mucosas como principais sítios de infecção. Ultimamente, a sua associação com neoplasias benignas e malignas da cavidade oral, principalmente o carcinoma epidermóide, tem sido mais evidente. O seu achado comum em epitélio de mucosa oral normal, amplamente divulgado na literatura, não permite inferências mais precisas quanto ao seu papel na carcinogênese (se agente etiológico principal, coadjuvante ou simples habitante do epitélio de revestimento da mucosa oral). São mais de 100 tipos já identificados, dos quais 24 já foram localizados na cavidade oral. Desses, 4 são particularmente importantes, os tipos 6 e 11 (que estão envolvidos nas lesões benignas do epitélio oral) e 16 e 18 (comprovadamente carcinogênicos e possivelmente envolvidos na etiologia de determinados carcinomas epidermóides orais). A ação desses dois últimos tipos está principalmente associada às oncoproteínas E6 e E7 produzidas pelos mesmos. A E6 liga-se, seqüestra e degrada a p53, importante proteína supressora de tumor. A segunda liga-se e seqüestra a pRb, também supressora de tumor, facilitando a liberação de E2F. Apesar do aprimoramento das técnicas de detecção do HPV nas lesões de mucosa oral, o seu envolvimento direto com os carcinomas orais não foi ainda devidamente comprovado, todavia a sua ação sinérgica com outros carcinógenos químicos e físicos, tais como o fumo e o álcool, em determinados carcinomas epidermóides nos parece o caminho mais correto para explicar a ação do papilomavírus humano na carcinogênese oral.

Current management of tonsillar cancer

Traditionally, risk factors for the development of tonsil cancer include the use of alcohol and/or tobacco, however a significant proportion of new cases develop in young patients without these risk factors. Recent investigation suggests that human papilloma virus (HPV) may serve as an etiology in such cases and represent a unique risk factor in a sub-set of patients. Irrespective of the etiology, in the majority of cases early carcinoma of the tonsil can effectively be treated using single modality therapy. While local-regional control and survival are similar following surgery or radiotherapy, primary surgery can be accomplished with minimal functional morbidity while reserving radiation for recurrent disease. In contrast, surgical salvage following external beam radiotherapy can be technically challenging and is often associated with a significant increase in surgical complications and functional morbidity. In contrast to early tonsillar disease, advanced tonsil cancer represents a clinical challenge that requires multimodality therapy. While advanced lesions are often treated with a combination of radiation, chemotherapy, and surgical ablation, management of the neck and distant metastases continues to present a therapeutic dilemma.

Human papillomavirus infections in children: the potential role of maternal transmission

To date, more than 100 types of human papillomavirus (HPV) have been identified. In the past 20 years, there has been an increasing interest in HPVs because of their potential role in the pathogenesis of malignant tumors. HPV infections are known to affect predominantly adult, sexually active age groups, whereas skin warts, at various anatomic sites, are usually associated with younger individuals. The modes of viral transmission in children remain controversial, including perinatal transmission, auto- and hetero-inoculation, sexual abuse, and, possibly, indirect transmission via fomites. Recent studies on perinatal infection with HPV have been inconclusive. It is still unclear how frequently perinatal infection progresses to clinical lesions, whether genital, laryngeal, or oral. Conflicting reports have been published on the prevalence of HPV infections in children. The current consensus is, however, that newborn babies can be exposed to cervical HPV infection of the mother. The detection rate of HPV DNA in oral swabs of newborn babies varies from 4% to 87%. The concordance of HPV types detected in newborn babies and their mothers is in the range of 57% to 69%, indicating that the infants might acquire the HPV infection post-natally from a variety of sources. HPV antibodies have been detected in 10% to 57% of the children, and there is usually no correlation between seropositivity and the detection of HPV DNA in either the oral or the genital mucosa. There is also evidence that transmission in utero or post-natal acquisition is possible. The mode of in utero transmission remains unknown, but theoretically the virus could be acquired hematogenously, by semen at fertilization, or as an ascending infection in the mother. The understanding of viral transmission routes is important, particularly because several vaccination programs are being planned worldwide. The serologic response to HPV detected in different populations of young women or women at risk of cervical cancer might be due to genital infections, but the possibility that HPV infection has been acquired earlier in life through the oral mucosa or respiratory tract cannot be ruled out.

Oral squamous cell carcinoma; from an hypothesis about a virus, to concern about possible sexual transmission

Nearly two decades ago, we produced the first evidence for the presence of viral nucleic acids in oral squamous cell carcinoma (OSCC) tissues, hypothesising that there may be a viral involvement in at least some OSCC. Subsequently, human papillomaviruses (HPV) in particular have been implicated in OSCC. Antibody responses to HPV are seen and HPV-DNA detected in tumors by us and many others, the virus being mainly HPV-16, the genotype associated with ano-genital cancer. HPV are seen by in situ hybridisation only in tumour and premalignant tissue but not in surrounding normal mucosa suggesting HPV has a causal relationship. HPV may also be integrated in the host genome, further suggesting a causal role. Studies of patients with OSCC have suggested possible sexual transmission of HPV. Recent studies have indicated that HPV may be aetiologically important particularly in some types of oropharyngeal cancer, at least in tonsillar carcinogenesis, and may represent an alternative pathway in carcinogenesis to the established factors of tobacco and alcohol. We have come a very long way in the two decades since our first suggestion of a viral aetiopathogenesis was greeted with incredulity, and data from on-going studies by the International Agency for Research on Cancer, Johns Hopkins Oncology Center and others are eagerly awaited.

Human papillomavirus as a risk factor for oral squamous cell carcinoma: a meta-analysis, 1982-1997

OBJECTIVE

Human papillomavirus (HPV) infection is a significant risk factor for uterine cervical carcinoma. However, the role of HPV infection in oral squamous cell carcinoma (OSCC) is less well defined. To determine the significance of the relationship of this virus in the progressive development of oral cancer, we estimated the risk of HPV detection in normal oral mucosa, precancerous oral tissue, and oral carcinoma using meta-analysis.

STUDY DESIGN

Case reports and clinical series published in English-language journals were retrieved by searching MEDLINE (January 1980-August 1998). Review articles were also examined to identify additional studies. Studies that used biochemical, immunologic, microscopic, or molecular analyses to detect HPV in tissue or cells derived from normal oral mucosa (n = 25), benign leukoplakia (n = 21), intraepithelial neoplasia (ie, dysplasia and carcinoma in situ; n = 27), and oral cancer (n = 94) were included in the meta-analysis. Information on sample size, age, sex, method of tissue preservation (ie, fresh, frozen, paraffin-embedded), assay, primer amplification region (early, late), high-risk versus low-risk genotype, and use of tobacco or alcohol was abstracted by one author (C.S.M.).

RESULTS

Data from 94 reports that analyzed 4680 samples were included in the meta-analysis. Analyses made by means of a random-effects model with and without adjustments for assay sensitivity showed increased probability of HPV detection in tissue with precancerous and cancerous features compared with normal mucosa. The likelihood of detecting HPV in normal oral mucosa (10.0%; 95% confidence interval [CI], 6.1%-14.6%) was significantly less than of detecting benign leukoplakia (22.2%; 95% CI, 15.7%-29.9%), intraepithelial neoplasia (26.2%; 95% CI, 19.6%-33.6%), verrucous carcinoma (29.5%; 95% CI, 23%-36.8%), and OSCC (46.5%; 95% CI, 37.6%-55.5%). Adjustment of findings for differences in assay sensitivity indicated that these estimates may be conservative. Overall, HPV was between 2 and 3 times more likely to be detected in precancerous oral mucosa and 4.7 times more likely to be detected in oral carcinoma than in normal mucosa. The pooled odds ratio for the subset of studies directly comparing the prevalence of HPV in normal mucosa and OSCC was 5.37, confirming the trend observed in the overall sample. The probability of detecting high-risk HPVs in OSCCs was 2.8 times greater than that of low-risk HPVs.

CONCLUSION

This meta-analysis indicates that HPV is detected with increased frequency in oral dysplastic and carcinomatous epithelium in comparison with normal oral mucosa. The findings provide further quantitative evidence that oral infection with HPV, particularly with high-risk genotypes, is a significant independent risk factor for OSCC.

Detection of human papilloma virus type 16 DNA in oral squames from normal young adults

We have employed the polymerase chain reaction (PCR) to detect Human Papillomavirus (HPV) type 16 in oral squames and mononuclear cells from 62 healthy young adult volunteers. Two groups were screened for the presence of this virus, but in not all cases was DNA obtained from the scrapes. In the first (n = 30), the results show that 43% of normal individuals harbour HPV 16 (a genital type) in their buccal mucosa, epithelium of dorsum of tongue and hard palate. In the second group (n = 18), 44% of individuals were positive for HPV 16 in their oral epithelial scrapes, while only 6% were positive for the same virus in mononuclear cells. Interestingly, in 2 cases, peripheral blood lymphocyte DNA gave a positive reaction with the HPV 16 primers. To investigate possible HPV infection of lymphocytes, a further 42 lymphocyte samples, taken from the same age group as the epithelial study group, were analysed. None of these lymphocytes were positive for the presence of HPV 16 DNA.

Oral diseases in HIV-1 infection

HIV-associated oral lesions have been reported since the beginning of the AIDS epidemic, be they fungal, viral, bacterial, neoplastic, or non-specific in origin. The most common lesions are oral candidiasis (OC; noted in several forms) and oral hairy leukoplakia (OHL). OC appears to be directly related to levels of immunosuppression while OHL, a newly described lesion, is associated with the Epstein-Barr virus. Although prevalence data for all types of oral lesions are scarce, this review identifies and describes those reported most often. Lesions associated with HIV may appear on most oral mucosal surfaces and may differ from those seen on other body areas. The role of saliva in reducing the potential for transmission of the HIV virus appears to be significant. Physicians and dentists should cooperate in the management of the HIV patient who has oral disease.

Oral manifestations of HIV infection in children

Human immunodeficiency virus (HIV) infection was first recognized in children in 1983 and has now assumed the proportions of a major public health challenge. This article briefly reviews, on the basis of the literature, the epidemiology, diagnosis, clinical and immunologic characteristics, and prognosis of HIV infection in children. The clinical oral manifestations in children are described on the basis of the literature and the personal observations of HIV-infected pediatric patients.

Demonstration of human papillomavirus DNA in a peripheral ameloblastoma by in situ hybridization

The peripheral ameloblastoma (PA) is a rare, extraosseous, odontogenic lesion usually located on the mandibular or maxillary gingiva. It often appears as an asymptomatic, firm, pink-red nodule with occasional secondary involvement of the underlying bone. Although histologically identical to primary intraosseous ameloblastoma, the PA is notably less aggressive in biologic behavior and rarely recurs following conservative treatment. It has a proposed dual histogenesis, while its etiology remains obscure. Several benign oral mucosal lesions have been found to be associated with various types of human papillomavirus (HPV). The following study uses a commercially available HPV DNA in situ hybridization technique to confirm the presence of HPV in a previously reported case of PA. Results were positive for HPV types 16/18 but negative for HPV types 6/11. The implications of these results with regard to etiology are discussed.

Human papillomavirus (HPV) infections and their associations with oral disease

More than 65 distinct types of human papillomavirus (HPV) have been identified to date. Several of the HPV types have been proposed as etiologic agents of squamous cell carcinoma. In the oral cavity, HPVs have been found associated with several benign squamous cell proliferations. Evidence from histology and DNA hybridization studies suggests that HPV is also involved in oral carcinogenesis. It is apparent, however, that substantial amount of confusion exists in the diagnosis of oral HPV infections. The keratotic, papillary lesions in the oral cavity are usually small and easily overlooked. The gross appearance of these viral lesions is not distinct enough to be readily diagnosed by the clinicians. Degenerative changes found on oral mucosa frequently simulate koilocytosis. Thus, caution should be exercised to avoid overdiagnosis of HPV infection in the oral cavity. The present review summarizes the current evidence available on HPV infections in general and on oral HPV infections in particular. The diagnostic techniques available as well as the problems encountered in the distinction of these lesions are also discussed in short.

Study of human papillomavirus in oral epithelial dysplasia and epidermoid carcinoma in the absence of tobacco and alcohol use

Human papillomaviruses (HPVs) are implicated in the etiology of benign and malignant mucosal lesions in both human beings and animals. The oncogenic role of HPV in malignant cervical lesions is well supported by DNA hybridization techniques and epidemiologic studies. However, the role of HPV in oral epithelial dysplasia and epidermoid carcinoma remains speculative. In this study the in situ hybridization technique was used to detect HPV genotypes 6 and 11; 16 and 18; and 31, 33, and 35 in tissue specimens from a study group consisting of 18 patients who were non-tobacco users, or non-tobacco and non-alcohol users, in whom oral epithelial dysplasia and epidermoid carcinoma developed. The hybridization findings were compared with those of a comparable control group of patients with similar lesions who had a history of tobacco and alcohol use. None of the study group cases was reactive with any of the DNA probes. Two cases of the control group showed positive hybridization with HPV DNA probe types 6/11 and 16/18. The implications of these findings are presented and discussed in an attempt to clarify the role of HPV in HPV-associated oral epidermoid carcinomas.

Detection of human papillomavirus (HPV) DNA in oral squamous cell carcinomas by in situ hybridization and polymerase chain reaction

A series of 156 formalin-fixed, paraffin-embedded biopsies from 40 patients with surgically-treated oral squamous cell carcinomas was analysed for the presence of human papillomavirus (HPV) infection by histopathological evaluation, in situ DNA hybridization and polymerase chain reaction (PCR). Epithelial changes suggesting a HPV lesion within, or adjacent to, the carcinoma lesions were found in 16 out of 40 patients (40%). Morphological signs of a flat HPV lesion were found in four cases (10%), those of inverted type in three cases (7.5%), and those of papillary type in nine cases (22.5%). HPV DNA was demonstrated in one of the lesions by in situ hybridization with biotin-labelled DNA cocktail probe containing HPV types 6, 11, 16 and 18. With the PCR technique, samples from 11 (27.5%) of the 40 patients proved to contain HPV DNA. Of these, HPV 6 was demonstrated in one case, HPV 16 in ten cases and HPV 18 in one case. HPV DNA was exclusively detected in the biopsies showing carcinoma tissue or its adjacent precancer lesions. No viral DNA was found in the biopsies derived from the tumour-free resection margins. These results provide further evidence to support the concept of HPV involvement in the aetiology of oral squamous cell carcinomas, most probably acting synergistically with other carcinogens.

Evaluation of oral and laryngeal specimens for human papillomavirus (HPV) DNA by dot blot hybridization

Human papillomavirus (HPV) is an infectious agent which is increasingly associated with mucosal cancers, in particular, cancer of the cervix. The present investigation was undertaken in an attempt to determine whether the Virapap human papillomavirus (HPV) DNA detection kit, originally designed for identification of HPV in exfoliated cervical cells could be employed in detection of HPV in biopsies of oral and laryngeal tissue samples, specifically oral squamous cell carcinomas, epithelial dysplasias, smokeless tobacco keratoses, and laryngeal papillomatosis. The ViraPap HPV DNA detection assay was found to be useful for HPV DNA identification in tissue samples from oral and laryngeal specimens.

Epithelial dysplasia produced by carcinogen pretreatment and subsequent wounding

Golden hamsters in which the tongues were pretreated with DMBA for 4 weeks, subsequently excised, and either received no treatment or received additional postexcisional applications of acetone or DMBA for 9 to 13 days exhibited histologic evidence of epithelial dysplasia; these dysplastic lesions stained positive for papillomavirus genus-specific antigens. Conversely, animals in which the tongues received the same pretreatment yet had no excision failed to show any dysplastic changes, even though the tongues received additional applications of DMBA. Furthermore, papillomavirus genus-specific antigens were not demonstrable. The animals in which the tongues received no pretreatment with DMBA for 4 weeks followed by excisional wounding showed normal healing, even though the tongues were post-treated with DMBA. Papillomavirus genus-specific antigens could not be demonstrated in this last group.

Ameloblastoma in young persons: a clinicopathologic analysis and etiologic investigation

Ameloblastoma, an odontogenic tumor of ectodermal origin, has been reported to arise, on rare occasions, in a primordial or dentigerous cyst of a young person. Numerous authors have suggested differing nomenclatures for these ameloblastomas (e.g., mural, unicystic, monocystic, intracystic, cystogenic, cystic, plexiform unicystic) and have sought to describe and classify the clinical and histopathologic features. These tumors have been characterized as a distinct variant exhibiting less aggressive behavior and a lower rate of recurrence than conventional ameloblastoma. Furthermore, various etiologic factors have been proposed for these cystic ameloblastomas, including (1) nonspecific irritational factors such as extraction, caries, trauma, infection, inflammation, or tooth eruption; (2) nutritional deficit disorders, and (3) viral infection. The files of the combined accessioned cases of Emory University's and Temple University's oral pathology laboratories were searched and a review of the literature was performed. Thirty-eight cases of mandibular ameloblastoma (37 intraosseous, 1 peripheral) in persons 19-year-old and younger were found from a combined total of 311 accessioned cases of ameloblastoma (12.2%). The average age at diagnosis was 10.4 years for the 18 males and 20 females. Of the 33 cases in which race was stated, 19 (57.6%) were white and 14 (42.4%) were black. In the 28 cases in which a clinical diagnosis was offered, fifteen (53.6%) were thought to be dentigerous cysts. Ten cases from patients less than 19 years old were investigated by means of an immunohistochemical staining technique for the detection of human papilloma virus (HPV) genus-specific structural antigen in formalin-fixed, paraffin-embedded tissue. Three of the ten cases (cases 31, 37 and 38) were positive for HPV capsid antigen, whereas none of ten randomly selected ameloblastomas in adults was positive. A discussion of the clinical and histopathologic comparative findings, with emphasis on treatment results and possible HPV etiology, is included. The preliminary nature of finding HPV in the tumor cells is stressed, with recommendation for further verification and typing with the more sensitive in situ hybridization technique.

Unusual HPV types in oral warts in association with HIV infection

Human papillomaviruses (HPV) are associated with certain oral soft tissue lesions, such as papillomas, warts, condylomata, and focal epithelial hyperplasia (FEH). HPV types 2, 6, 11, 16, and 18 have been identified in some of these oral lesions, while HPV 13 and 32 are associated with FEH. Little is known about the HPV types in oral warts of persons infected with human immunodeficiency virus (HIV). In this study, oral warts in 17 HIV-seropositive individuals were biopsied. Southern blot analyses were performed and the HPV types found were HPV 7 (7/17), 13 (1/17), 32 (1/17), and 18 (1/17). The presence of HPV type 7 is unusual in that it normally is found only in butcher's warts. There was no correlation between HPV type, histopathology, and clinical appearance of the lesions examined, except that the flat (FEH type) warts contained HPV types 13, 18 and 32 (1 of each). HIV infection appears to predispose individuals to oral infection with unusual HPV types.

Viruses and salivary gland disease: are there associations?

Viruses can cause sialadenitis and may be associated with other diseases of salivary glands, particularly immunologically mediated and neoplastic lesions. The evidence that such an association with Sjögren's syndrome is causal is reviewed here and shown to be fairly tenuous at present.

Human papillomavirus (HPV) DNA sequences in oral precancerous lesions and squamous cell carcinoma demonstrated by in situ hybridization

A series of routinely processed, paraffin-embedded biopsies from 73 surgically treated oral precancerous lesions (OPL) (22 cases), and oral squamous cell carcinomas (SCC) (51 cases), was first screened using an in situ DNA hybridization technique with a human papillomavirus (HPV) DNA probe cocktail containing the 35S-labelled DNA of HPV types 6, 11, 13, 16, 18 and 30. The specific HPV types in lesions shown to contain HPV DNA in this procedure were further analysed by using in situ hybridization and the 6 HPV DNA probes separately. A total of 12/73 (16.4%) of the lesions proved to contain HPV DNA; 6/51 (11.8%) carcinomas and 6/21 (28.6%) dysplasias. The most frequent sites of HPV DNA-positive lesions were palate (4/7; 57%), followed by the floor of the mouth (2/8; 25%), the tongue and gingiva (11.8%). HPV 13 or HPV 30 were not found in any of the lesions studied. HPV 11 DNA was demonstrated in 2 mild dysplasia lesions, but not in carcinomas. One additional mild dysplasia proved to contain HPV 6 DNA. HPV 16 DNA was present in 5 biopsies; 3 carcinomas and 2 dysplasias. In one of the HPV 16-positive carcinomas, HPV 18 DNA was simultaneously present. HPV 18 alone was found in 3 additional carcinomas and in one moderate dysplasia lesion. The results confirm the recently reported evidence on HPV involvement in OPL and oral cancer. The implications of these findings are discussed in terms of the possible HPV etiology of oral SCC.(ABSTRACT TRUNCATED AT 250 WORDS)

Papillomaviruses: the current status in relation to oral disease

Human papillomaviruses of different types are associated with a variety of benign oral lesions and may be associated with some premalignant and malignant oral lesions. However, since it is now clear that a variant of human papillomavirus 16 is harbored by normal oral mucosa, as well as by premalignant and malignant lesions, such associations may not necessarily always be causal. The rapid progress of recent research in this field is reviewed, with particular reference to oral disease, and the current status is discussed.

In situ DNA hybridization analysis of human papillomavirus (HPV) sequences in benign oral mucosal lesions

A series of 144 surgically treated benign oral mucosal lesions were analysed using an in situ DNA hybridization technique with 35S-labeled human papillomavirus (HPV) DNA probes to demonstrate the DNA of HPV types 6, 11, 13, and 16, in routinely processed, paraffin-embedded biopsy specimens. These lesions and an additional 62 benign oral mucosal biopsy specimens (total, 206 specimens) were also assessed by the indirect immunoperoxidase (IP-PAP) technique to detect the expression of HPV structural proteins (viral antigens). A total of 54/206 (26.2%) lesions were observed to express HPV antigens, being found in 45/92 (48.9%) of the squamous cell papillomas/condylomas, in 1/54 fibrous hyperplasias, in 1/8 true fibromas, and in 7/8 (87.5%) of the focal epithelial hyperplasia (FEH) lesions. Of the HPV DNA-positive lesions, 15/45 (33.3%) expressed HPV antigens, the expression not being related to any particular HPV type. HPV DNA sequences were found in 45/144 (31.3%) of the lesions. HPV DNA was present with the highest frequency in FEH (83.3%), followed by the papilloma/condyloma group (33.8%), papillary hyperplasia (28.6%), fibrous hyperplasia (24.4%), and true fibromas (14.3%). The most frequent HPV type was HPV 11, representing 37.8% of the DNA-positive lesions. HPV 13 DNA, previously regarded as specific to FEH, was disclosed as a single HPV type in seven cases, and as a double infection by HPV 11 and 13 in an additional three cases, including all five morphologically distinct entities. Noteworthy is the discovery of the high-risk HPV type 16 DNA in 17.8% of the DNA-positive lesions, four papilloma/condyloma lesions, three fibrous hyperplasias, and one FEH.(ABSTRACT TRUNCATED AT 250 WORDS)

Detection of human papillomavirus DNA in biopsies of human oral tissue

We have employed molecular probes produced from DNA fragments of human papillomavirus, cloned into prokaryotic vectors, to detect virus nucleic acid sequences in extracts of human oral tissues. The study was conducted with duplicate coded snap-frozen tissue biopsies from which frozen sections had been taken to accurately assess the pathology of each particular sample. The results show that a large proportion of the oral biopsies contained DNA which hybridized to the viral DNA probes, even under conditions of high stringency. The presence of virus did not correlate with neoplasia in the tissues examined, but HPV like sequences were found in a high proportion (80%) of biopsies taken from areas of keratosis and lichen planus and also in 41 to 46% of normal and tumour tissues.

Human papillomavirus (HPV) in oral squamous cell papillomas

One hundred and forty oral squamous cell papillomas (SCPs) were subjected to immunocytochemical staining for papillomavirus antigen using the immunoperoxidase-PAP method 41% of the oral squamous papillomas showed positive intranuclear staining, 50% were negative and the remaining 9% showed both intranuclear and cytoplasmic staining. In view of these findings it is suggested that a review of the etiology of lesions diagnosed as oral SCPs should be considered.

Demonstration of human papillomavirus DNA in oral condyloma acuminatum

Condyloma acuminatum arising on oral mucous membranes exhibits distinct histopathological features that allow for differentiation from the more common squamous papilloma. These lesions are parakeratinized with cryptic invagination of cornified cells extending into an acanthotic spinous cell layer. Superficial spinous layer koilocytosis is a prominent feature and the condylomatous papillomas exhibit a tendency for sessile architecture. Among 62 instances, the average age was 39.7 years with a predilection for the 3rd and 4th decades. The male to female ration was 5.7:1 and the tongue, gingiva and lips were the favored sites. Whereas 25% of the evaluated cases demonstrated upper spinous layer papillomavirus common antigen immunoreactivity, DNA in situ hybridization under conditions of high stringency disclosed the presence of human papillomavirus Types 6, 11 or related genomes in 85% of the lesions. A single case was found to harbor human papillomavirus Type 2.

Detection of human papillomavirus DNA in oral mucosal lesions using in situ DNA-hybridization applied on paraffin sections

The in situ DNA hybridization technique, carried out under stringent conditions, was used to detect human papillomavirus (HPV) DNA of types 6, 11, and 16 in paraffin sections of 32 surgically treated oral mucosal lesions. Expression of HPV structural proteins was analyzed by means of the immunoperoxidase (IP-PAP) method. A total of 10 (31.3%) of the 32 lesions proved to express HPV antigens, which were found in 4 of 7 squamous cell papillomas, in 2 of 2 classic condylomas, in 2 of 10 papillary hyperplasias, and in 2 of 3 leukoplakia lesions. Two of the squamous cell papillomas contained HPV 6 DNA, and 4 additional lesions were positive for HPV 11 DNA. In one of the condylomas, a double infection by HPV 6 and 11 was found, while the second was positive for HPV 11 alone. Both the HPV antigen-positive papillary hyperplasias contained HPV 6 DNA, as did the HPV antigen-positive leukoplakia lesions. Of the latter, one was infected by HPV 6 and 11. DNA of the "high-risk" HPV 16 was contained in two lesions: one lichen planus lesion and one of the two squamous cell carcinomas. The results confirm the previously reported evidence of HPV involvement in oral mucosal lesions. The implications of these findings are discussed in terms of the well-established premalignant character of oral leukoplakia and oral lichen planus, although far less commonly versus leukoplakia, with special emphasis on the discovery of the "high-risk" HPV 16 in the latter as well as in oral cancer.(ABSTRACT TRUNCATED AT 250 WORDS)

Detection of papillomavirus DNA in oral papillomas and carcinomas: application of in situ hybridization with biotinylated HPV 16 probes

Four oral papillomas and 7 carcinomas were studied for the presence of HPV DNA by means of in situ hybridization. Hybridization was carried out with a HPV 16 probe labelled with biotin under different conditions (nick translation/photobiotin). Subsequently, a modified biotin-avidin-alkaline phosphatase procedure was used to visualize virus infected cells. Four/4 papillomas and 4/7 carcinomas were seen to contain HPV harbouring cells. Positive cells were located at intermediate and superficial cell layers in papillomas and in keratinized zones in carcinomas. Analogous results were found with nick translated and photobiotinylated probes. DNA-biotinylation in conjunction with the biotin-avidin-alkaline phosphatase detection system proved to be a sensitive, convenient and rapid modification of in situ hybridization.