Occurrence of papillomavirus structural antigens in oral papillomas and leukoplakias

Development of head and neck pathology in Europe

This review gives a brief history of the development of head and neck pathology in Europe from a humble beginning in the 1930s to the explosive activities the last 15 years. During the decades before the introduction of immunohistochemistry in the 1980s, head and neck pathology grew as a subspeciality in many European countries. In the late 1940s, the Institute of Laryngology and Otology with its own pathology laboratory was founded in London, and in 1964 the World Health Organization (WHO) International Reference Centre for the Histological Classification of Salivary Tumours was established at the Bland-Sutton Institute of Pathology, also in London. International collaboration, and very much so in Europe, led to the publication of the first WHO Classification of Salivary Gland Tumours in 1972. In the 1960s, a salivary gland register was organised in Hamburg and in Cologne the microlaryngoscopy was invented enabling microscopic endoscopic examination and rather shortly afterwards a carbon dioxide laser attached to the microscope became established and laryngeal lesions could be treated by laser vaporisation. During the last three decades, the use of immunohistochemistry supplemented with cytogenetic and refined molecular techniques has greatly facilitated the pathological diagnostics of head and neck lesions and has had a huge impact on research. Collaboration between different European centres has drastically increased partly due to establishment of scientific societies such as the Head and Neck Working Group (HNWG) within the European Society of Pathology and the International Head and Neck Scientific Group (IHNSG). A very large number of European pathologists have contributed to the 2nd, 3rd and 4th WHO books, and are involved in the upcoming 5th edition. Accredited educational meetings and courses are nowadays regularly arranged in Europe. Numerous textbooks on head and neck pathology have been written and edited by European pathologists. The increased collaboration has created larger series of tumours for research and new entities, mainly defined by their genetic abnormalities, are continuously emerging from Europe, particularly regarding salivary gland neoplasms and "undifferentiated" sinonasal tumours. These findings have led to a better and more precise classification and open the possibilities for new treatment strategies.

Detection and typing of human papillomaviruses (HPV) in malignant, dysplastic, nondysplastic and normal oral epithelium by nested polymerase chain reaction, immunohistochemistry and transitional electron microscopy in patients of northern Greece

OBJECTIVES

To evaluate the role of HPV in oral carcinogenesis, we examined the prevalence of HPV in malignant, potentially malignant and normal oral epithelium and studied the relation of HPV prevalence with other factors obtained from the patient's records.

MATERIALS AND METHODS

Our material consisted of 291 tissue specimens from 258 individuals. From every individual formalin fixed and paraffin embedded tissues were examined by nested Polymerase Chain Reaction (NPCR) for the detection of HPV DNA and by immunohistochemistry (IHC) for the in situ detection of HPV L1 protein. Positive PCR products were sequenced in order to type HPVs. Also 33 fresh tissues were obtained, fixed and used to detect HPV particles by transitional electron microscopy (TEM).

RESULTS

HPV was detected in 32.9% of the tissue specimens by NPCR, in 4.7% by immunohistochemistry and in 28.1% by TEM. In detail, by nested PCR HPV L1 DNA was detected in 40% of normal tissues, 40% of fibromas, 35.8% of non-dysplastic leukoplakias, 31.6% of dysplastic leukoplakias and 22.2% of oral squamous cell carcinomas. The HPV viral load of 96.5% of the samples was very low (1 viral copy per 10(2)-10(4) cells). HPV16 prevails in all histological groups in 89-100%.

CONCLUSION

We conclude that HPV does not seem, from the specific sample examined, to play a substantial role in oral carcinogenesis. However, it cannot be excluded that HPV could be involved in oral carcinogenesis only in cases with high viral load or at early stages of carcinogenesis possibly through the hit-and-run mechanism.

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.

Human papillomavirus and head and neck cancer: epidemiology and molecular biology

BACKGROUND

Human papillomaviruses (HPV) are known to cause cancers of the cervix and other anogenital tract sites. Molecular biology has provided some evidence as to the specific mechanisms involved in the HPV-related carcinogenesis. Epidemiologic and molecular biology studies have also suggested that HPV infection may be associated with cancers of the head and neck.

METHODS

This review summarizes the biology of HPV and its potential etiologic role in head and neck cancer. Published reports were used to determine the prevalence of HPV in benign, precancerous, and neoplastic lesions of the oral cavity, pharynx, and larynx. The prevalence was also examined by head and neck site, HPV type, and method of HPV detection. In addition, the occurrence of HPV in normal head and neck tissue, epidemiologic factors related to HPV infection, and clinical implications are discussed.

RESULTS

Overall, the frequency of HPV in benign and precancerous lesions ranged from 18.5% to 35.9%, depending upon the detection methodology. Based upon the most sensitive method of detection, polymerase chain reaction (PCR), the overall prevalence of HPV in head and neck tumors was 34.5% (416 of 1205 tumors). The majority of HPV-positive tumors contained the "high risk" HPV types 16 (40.0%) and 18 (11.9%). Among head and neck sites, HPV was most often detected in tumors of the oral cavity (59%), followed by the pharynx (43%), and larynx (33%). The frequency of HPV positivity in oral samples from healthy individuals ranged from 1% to 60%. A limited number of descriptive and analytic epidemiologic studies have indicated that age (<60 years) and sex (male) were associated with the presence of HPV in the tumor, whereas tobacco and alcohol use were not. The relationship between HPV and survival is unclear, with few comprehensive studies currently available.

CONCLUSIONS

The prevalence of HPV, particularly the high-risk types, suggests a potential etiologic role for the virus in head and neck cancer. Molecular biology has provided important data on the interaction of the HPV oncoproteins with genes important in cell cycle control. Nonetheless, more basic research is needed to describe the physical state of the virus in a variety of cell types and the interaction with other genes. In addition, epidemiologic research is required to further understand the association between HPV and demographic and other risk factors as well as possible routes of transmission. Finally, much work is warranted to provide a definitive assessment of the prognostic significance of HPV in head and neck cancer.

[Detection of human papillomavirus (HVP)-DNA in oral manifestation of lichen planus]

Human papilloma viruses (HPV) can be detected in different epithelia with the help of the polymerase chain reaction (PCR). The role of HPV in the development of anogenital cancers has been intensively studied, and current evidence shows that most cervical cancers are associated with so-called high risk HPV types (e.g. HPV 16 and 18). HPV-infections can also be demonstrated in oral premalignant lesions and squamous cell carcinomas. Depending on the sensitivity of the detection method, 40-67% of leukoplakias, 2.5-76% of squamous cell carcinomas and 0-87% of cases of lichen planus were described to be infected with HPV 16 or 18. Whether lichen planus can be considered as a premalignant lesion is still controversial. By the use of PCR and hybridization we found infections with the high risk HPV types 16, 18 and 31 in 42% (3/7) of the patients with lichen planus. Further investigations with a higher numbers of cases in combination with the analysis of the viral gene expression as well as the clinical and histological control of the corresponding regions are necessary. The aim of these studies is to find out the prognostic value of the HPV infection for this facultative premalignant disease.

Human papillomavirus in oral premalignant lesions

The aetiology of oral premalignant lesions is generally accepted to be multifactorial. Tobacco and alcohol are established as important cofactors in malignant development in the oral cavity, but in addition microorganisms, such as human papillomavirus (HPV), have gained much interest over the past decade. For many years, HPV has been accepted as an important cofactor in the development of cervical cancer, originating from a mucous membrane with similarities to the oral mucosa. 49 patients with oral premalignant lesions and 20 control patients with normal oral mucosa and no history of HPV infection were examined for the presence of HPV by immune histochemical staining using the peroxidase anti-peroxidase technique (PAP), DNA-DNA in situ hybridisation (ISH), and polymerase chain reaction (PCR) analysed by Southern blot hybridisation with an HPV 16 specific probe. The investigations revealed that HPV was found in 62.5% of the verrucous leucoplakias, 50.0% of the erythroplakias, 45.5% of the homogeneous leucoplakias, 33.3% of erythroleucoplakias and in 12.5% of the nodular leucoplakias. An overall HPV detection rate in the examined premalignant lesions was 40.8% and no patients in the control sample were positive. Concerning oral cancer development, it seems likely that HPV may be a cofactor, as 100% of patients who developed oral cancers within 4-12 years were all positive for HPV, one being positive for HPV 16.

Human papillomavirus expression in oral mucosa, premalignant conditions, and squamous cell carcinoma: a retrospective review of the literature

OBJECTIVES

The literature of human papillomavirus detection in normal oral mucosa and oral lesions associated with the dysplastic progression of epithelium was reviewed to help define the role of this virus in the development of oral squamous cell carcinoma.

STUDY DESIGN

All available data from published studies were analyzed by chi-square test for association between the human papillomavirus and age, gender, race, DNA type, location, lesional dysplastic progression, method of detection, tissue preservation, and use of tobacco and alcohol.

RESULTS

Human papillomavirus was identified with increasing frequency in normal oral mucosa (13.5%), benign leukoplakia (14.8%), intraepithelial neoplasia (18.5%), squamous carcinoma (26.2%), and verrucous carcinoma (27%). It was detected in oral squamous cell carcinoma significantly (p < 0.005) more often (37.1%; 122 of 329) in studies that used a high sensitivity assay (polymerase chain reaction) than studies that used moderate sensitivity assays (25.2%; 84 of 334) (e.g., Southern blot hybridization) and low sensitivity assays (16.9%; 61 of 362) (e.g., immunohistochemistry, in situ hybridization). Human papillomavirus DNA was detected significantly more often (p < 0.001) in frozen oral squamous cell carcinoma (51.6%; 115 of 223) than paraffin-embedded tissue (21.7%; 136 of 628). High-risk human papillomaviruses (2, 16, 18) were detected in 81.4% of OSCCs that contained the virus compared with low-risk human papillomavirus genotypes (6, 11) in 17.9% of oral squamous cell carcinoma that contained the human papillomavirus (p < 0.001). In studies that analyzed the use of chemical cofactors, the use of tobacco and alcohol (87.3%) was associated more often with oral squamous cell carcinoma than the presence of human papillomavirus (51.3%), however, the difference was not significant.

CONCLUSION

High-risk human papillomavirus genotypes have a significant association with oral squamous cell carcinoma. However, the presence of this virus in a high proportion of oral normal mucosa makes the virus alone a poor prognosticator of progression to malignancy.

Oral manifestations of selected sexually related conditions

The incidence of certain microbial infections occurring in the oropharynx is well documented, but infection by other pathogens, although highly probable, has not been established with certainty. Considerable recent interest in the incubation period of various infections and improved community surveillance programs combine to ascribe infection to specific incidents. It is prudent for health care personnel to acknowledge the presence of many sexually transmitted diseases in the oropharynx and consider them in the differential diagnosis of many well-established conditions.

A possible role for human papillomaviruses in head and neck cancer

Human papillomaviruses (HPVs) cause benign tumors in the respiratory tract. Mounting evidence suggests that they also play a role in the etiology of a subset of head and neck cancers. Carcinomas in patients with a history of recurrent respiratory papillomatosis clearly are caused by persisting HPV interacting with one of more carcinogenic agents. Verrucous carcinomas of the oral cavity, tonsillar and tongue carcinomas are strongly linked with HPVs, based on molecular epidemiologic data. Tonsillar cancer have been shown to express HPV RNA, presumed necessary to induce and maintain a carcinoma, supporting a viral etiology. This paper reviews the molecular and cellular basis for considering HPVs as causative agents of cancer, and reviews the literature that considers the possible role of HPVs in head and neck cancer.

Oral leukoplakia

Leukoplakia has evolved as a clinico-pathologic concept over many years, with the current clinical designation being accepted worldwide. Reflective of the biology of leukoplakia is the concept of cellular atypia and epithelial dysplasia. Adding to a better understanding of leukoplakia in general has been the definition of relevant clinical subsets which, in some cases, includes etiology (snuff), while in other cases a verrucous clinical appearance will suggest a more aggressive anticipated behavior pattern. Tobacco usage, in many of its forms, remains the prime etiologic factor; however, other considerations also apply. More recently, the potential etiologic role of Candida albicans has been stressed, as well as its possible role in carcinogenesis. So-called oral hairy leukoplakia has been defined in relation to a possible Epstein-Barr viral infection, usually in the immunosuppressed patient. Other viruses, human papilloma virus in particular, have been implicated in leukoplakia, while genetic alterations involving tumor suppressor elements (p53) have also been investigated. Finally, the management of this common condition remains a variable and includes local, topical, and systemic therapies such as anti-oxidants, carotenoids, and retinoids.

Association of p53 expression with cytokinetics and HPV capsid antigen prevalence in oral carcinomas

p53 protein expression in oral squamous cell carcinomas (SCCs) was studied in relation to presence of HPV capsid antigens and tumour cell kinetics. The protein and viral antigens were determined from 64 SCCs employing immunoperoxidase and immunofluorescence techniques, respectively. Cell kinetics were assessed by in vitro bromodeoxyuridine labelling. Different levels of p53 were detected in 61% cases. Well-differentiated SCCs (88%) showed increased p53 expression compared with the less differentiated ones. In SCCs with higher cell proliferation rate (LI%, 13.25 +/- 4.64) the expression was almost absent. However, it was higher in stage I than in stage II/III carcinomas and occurred in 54.5% and 75% cases of HPV antigen-positive and -negative (or very little) SCCs, respectively.

Oral cancer and human papillomaviruses: is there a link?

Cancer of the oral cavity accounts for almost 56,000 new cases in India each year totalling almost 30% of all cancer cases in the country. Despite the numerous advances in etiology and epidemiology, the mechanisms involved in oral carcinogenesis remain obscure. Current research has provided some provocative results, suggesting an association between human papillomavirus (HPV) and development of squamous cell tumors including oral cancer. Evidence has been presented showing HPV infection of the oral mucosa and its relation to neoplastic changes. However a clear cut association as is evident in the uterine cervix is not yet available. However, considering the many similarities between oral and cervical oncogenesis, many of the HPV induced changes in the cervix may also be applicable to the oral mucosa. This paper studies the evidence for the possible role of HPV infection in oral carcinogenesis, the uterine cervix as a model for HPV mediated carcinogenesis, and tries to determine if similar mechanisms could exist in both cases.

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.

Viruses and chronic disorders involving the human oral mucosa

Viruses have been implicated in the etiology of several chronic disorders of the oral mucosa. Most of these associations have been with DNA viruses, particularly certain herpesviruses, which are associated, for example, with some cases of erythema multiforme and with hairy leukoplakia. Papillomaviruses are associated with various papillomatous lesions, focal epithelial hyperplasia, and possibly with some carcinomas. Viruses may possibly be associated with recurrent aphthae, Behçet's syndrome, and some dermatoses. The literature concerning these possible associations is reviewed. However, much more research needs to be done before the full story of viral associations with oral mucosal disorders can be written.

Changing trends in oral cancer in the United States, 1935 to 1985: a Connecticut study

An extensive epidemiologic study was undertaken in an attempt to analyze patterns of oral cancer distribution and demography in Connecticut between 1935 and 1985. Sources of data for the investigation included both the Connecticut Tumor Registry (CTR) and the University of Connecticut Oral Pathology Biopsy Service. During the 51-year study period, 9,708 cases of primary oral cancer were reported to the CTR. Male age-adjusted incidence rates for overall oral cancer remained stable between 1935 and 1964 (14.5 to 14.8 per 100,000), with a gradual decline to 10.9 per 100,000 in the early 1980s. In contrast, age-adjusted rates for females advanced approximately threefold, from 1.4 per 100,000 in the 1930s to 4.1 per 100,000 in the early 1980s. There was a decrease in age-specific rates of oral cancer in males aged 70 and older; in contrast, age-specific incidence rates in females increased steadily over the same period. It was also found that female birth cohorts born in 1900 and later exhibited higher oral cancer incidence rates than those of previous cohorts. Between the 1960s and the present, male patients 30 to 39 years of age exhibited a nearly fourfold increase in oral cancer incidence; this was not observed among similarly aged females. Connecticut counties with highest oral cancer incidence rates in both sexes were the more densely populated Hartford and New Haven counties. In general, the picture of oral cancer, as revealed through analysis of cases accessioned by the University biopsy service between 1975 and 1986, exhibited similar trends to those disclosed by analysis of CTR data.(ABSTRACT TRUNCATED AT 250 WORDS)

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.

Human papilloma virus in erosive oral lichen planus

Several types of human papilloma viruses (HPV) have been associated with benign and malignant squamous cell tumours of mucosal epithelium. To identify HPV in erosive oral lichen planus (OLPe), considered as a premalignant lesion, tissues from 20 patients were examined by Southern blot hybridization with 32P-labeled HPV DNA probes. Type 11 was found in 6 of the lesions while HPV types 6, 16 and 18 were not detected in any of the tissues examined. Using a type-specific polymerase chain reaction (PCR) assay for HPV-6, 11, 16 and 18, HPV-11 was detected in 8 of the samples (all of those positive by Southern blot), and, in addition, HPV-6 was found in 5 samples and HPV-16 in 3 samples. Overall, by the more sensitive PCR assay, 65% of samples were positive for HPV DNA. The finding of HPV DNA in many of the samples using two different techniques indicates a high prevalence of HPV in the OLPe afflicted oral mucosa. However, the role of HPV in the pathogenesis of OLPe has yet to be determined.

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.

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.

Oral squamous papillomas: detection of HPV DNA by in situ hybridization

Oral squamous papillomas were segregated from other papillary lesions on the basis of histopathologic features. Twenty representative papillomas were evaluated for the presence of papillomavirus genus-specific antigen with the use of an immunoperoxidase technique. These same tumors were analyzed for human papillomavirus (HPV) types 2, 4, 6, and 11 with biotinylated full-length double-stranded DNA probes by in situ hybridization. Only one case exhibited papillomavirus antigen reactivity. Alternatively, seven of twenty cases (35%) yielded positive results for HPV 6 or 11 DNA; one papilloma exhibited a dual infection with both HPV 2 and 6 when assayed under conditions of high-stringency hybridization. It is concluded that some oral squamous papillomas harbor HPV genotypes akin to those encountered in genital tract condylomas. Viral DNA can be detected in the absence of capsid antigen immunoreactivity, thereby obviating the use of antigen detection assays for determining the presence or absence of virus.

Human papillomavirus type 2 DNA in oral and labial verruca vulgaris

Twenty instances of verruca vulgaris, equally divided between oral mucosa and lip vermillion, were assayed for the presence of human papillomavirus (HPV) capsid antigen and type-specific DNA employing in situ hybridization methods. All 10 cases arising on lip vermillon expressed capsid antigen and harbored HPV Type 2 genomes as assessed under conditions of high stringency DNA hybridization. Oral verrucae rarely expressed capsid antigen; HPV Type 2 genomes were encountered in 20% of the cases.

Demonstration of papillomavirus structural antigen in human urinary bladder neoplasia

Clear cells showing characteristic features of koilocytotic atypia were found in 41 (82%) of 50 paraffin sections of urinary bladder tumour. Papillomavirus common structural antigen was detected in seven (14%) of the samples using an avidin-biotin peroxidase staining technique. The results suggest a role for the human papillomavirus in the aetiology of urinary bladder neoplasia.

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.

Oncogenic potential of sexually transmitted viruses with special reference to oral cancer

Recent changes in social mores have been accompanied by a noted increase in the frequency of sexually transmitted diseases. Viruses that have been identified as causative agents for a large proportion of these diseases have also been associated with various malignant states. Concomitantly, the number of cases of oral cancer (considered to occur usually around or after the fifth decade of life) reportedly has been increasing among young adults. The oncogenic potential of several sexually transmitted viruses (HSV, HPV, CMV, and LAV/HTLV III) and their possible role in the development of malignant conditions, in particular oral cancer, are discussed in this review.

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.

Human papillomavirus 25-related DNA in solitary keratoacanthoma

Solitary keratoacanthomas of 32 patients were screened for the presence of human papillomavirus (HPV) 25 DNA, which was originally isolated and molecularly cloned from warts of an epidermodysplasia verruciformis (Ev) patient. Biotinylated virus DNA was hybridized in situ to thin sections obtained from paraffin-embedded material. HPV DNA was detected in 12 of 32 tumors under stringent conditions, and in 2 additional tumors under relaxed conditions.

Local immunoreactivity and human papillomavirus (HPV) in oral precancer and cancer lesions

A retrospective longitudinal study was performed on 20 patients with oral leukoplakia, 10 of which developed an oral squamous cell carcinoma, to assess whether any alterations in the local immunologic reactivity could be found of value in predicting the subsequent behavior of the lesions. During the major period of follow-up, the relative frequency of in situ IgA-producing plasma cells was significantly higher in biopsies from patients subsequently developing cancer than in patients showing no cancer development. Preceding the malignant transformation by 12 to 15 months, however, a remarkable shift from IgA to IgG plasma cell predominance was noticed in the biopsies of the cancer series, not detectable in the non-cancer group. HPV group specific capsid antigens were found in seven cases of the cancer series and in six of the non-cancer group. The possible diagnostic implications of these results are discussed.

Human papillomavirus type 2 DNA in oral verrucous carcinoma

Tissues from patients with oral verrucous carcinoma were examined for the presence of human papillomavirus (HPV). The tissues were stained for the presence of the type common papillomavirus antigen by immunohistochemical staining and the presence of HPV DNA was determined by in situ hybridization with biotin-labelled HPV DNA probes. Seventeen tissue specimens were obtained from 9 patients, and included pre-malignant lesions and primary and recurrent tumors. One pre-malignant lesion was positive for papillomavirus structural antigen. This lesion and lesions from 2 other patients hybridized at low stringency (Tm-35 degrees) to 3 different HPV probes. By hybridization under high stringency conditions (Tm-20 degrees), the virus in each case was identified as being HPV2.

Peroxidase-antiperoxidase evaluation of human oral squamous cell papillomas

In human beings, the viral origin of condylomatous lesions of the mouth and cervix, multiple papillomas, and verruca vulgaris of the larynx has been established. The viral origin of papillomatosis in rabbits and dogs has also been documented. The literature, however, shows no conclusive evidence of a viral origin of human oral squamous cell papillomas (SCP). The purpose of this study was to use the peroxidase-antiperoxidase (PAP) staining technique to determine whether human papillomavirus (HPV) antigens exist in serial step sections of human oral SCP. Fifty human oral SCPs were randomly selected from the department files, and tissue sections were subjected to an indirect immunoperoxidase-PAP technique. Evidence of HPV-Type I virus antigens was found in 2 of 50 papillomas studied (2 of 194 tissue sections). This suggests that all oral SCPs are not of viral antigen.

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.

Identification of human papillomavirus types in oral verruca vulgaris

Eleven oral verruca vulgaris specimens were examined for the presence of papillomavirus structural antigens by reaction with antibody to type-common antigens and detection by the avidin-biotin-peroxidase complex method. The specimens were also examined by in situ hybridization with biotin-labelled human papillomavirus (HPV) DNA to determine the specific HPV types present in the lesions. Six of the 11 specimens were positive for papillomavirus structural antigens. Of these 6, 5 hybridized to the HPV Type 2 (HPV2) probe and one to the HPV4 probe.

Immunologic localization of filaggrin in human oral epithelia and correlation with keratinization

Localization of filaggrin, a human epithelial structural protein, was investigated by indirect-immunofluorescence microscopy of oral mucosa. Thirty specimens were tested, 10 each of palate, gingiva, and buccal mucosa. Orthokeratinized and parakeratinized specimens displayed immunofluorescence within the stratum corneum, stratum granulosum, and upper stratum spinosum. Within the stratum corneum, the reaction was diffuse. Within the stratum granulosum and spinosum, the reaction was in a granular pattern, in a perinuclear position. Several of the nonkeratinized specimens had a negative reaction; however, most displayed a very weak, scattered reaction in a granular pattern within the most superficial cells. The presence of filaggrin in keratinized palate was confirmed by immunoblot studies with the same antibody. Profilaggrin was detectable in representative nonkeratinized and parakeratinized oral tissues, as well as in keratinized palatal epithelium. The localization of filaggrin is consistent with its possible function as the interfilamentous matrix protein within cells of the stratum corneum, and with its derivation from a cross-reactive precursor protein stored in keratohyaline granules. A strong positive correlation was found between the degree of keratinization and the amount of immunofluorescence; therefore, filaggrin and related antigens may be useful and sensitive marker proteins for epithelial keratinization.

Identification of genital tract papillomaviruses HPV-6 and HPV-16 in warts of the oral cavity

Warty lesions of the oral cavity were examined for etiologic association with genital tract papillomaviruses HPV-6, HPV-11, and HPV-16. DNAs extracted from ten oral biopsies were screened for HPV genomic sequences by Southern transfer hybridization with 32P-labeled viral DNA probes. Nonstringent hybridization with an HPV-6 probe revealed papillomavirus DNA sequences in four of seven tissues with histologic evidence of papillomatosis, in none of two tissues without histologic evidence of papillomatosis, and in one tissue that was not examined by histology. Stringent hybridization tests with HPV-6 and HPV-16 probes identified the genome in one tissue as being HPV-16, in a second tissue as being HPV-6 subtype a, and in a third tissue as HPV-6 (subtype unidentified); papillomavirus DNA sequences in two tissues are as yet not identified. An additional case of HPV-6 or HPV-11 related oral cavity lesion was diagnosed by in situ hybridization of paraffin sections with a 35S-labeled, mixed HPV-6 + HPV-11 probe. The hybridization in the positive section was extensive and confined to epithelial nuclei. The oral lesions associated with genital tract papillomaviruses were asymptomatic, multiple or single, and were located in different parts of the oral cavity, for example, on the gingivae, on the tongue, on the lip, on the tonsillar pillar, and on the floor of the mouth.

Proliferative verrucous leukoplakia. A long-term study of thirty patients

Up to 6% of oral leukoplakia, a relatively common mucosal disease, can be expected to become malignant. This report describes a long-term study of 30 patients in whom a particular form of leukoplakia was identified and labeled proliferative verrucous leukoplakia (PVL), a disease of unknown origin, which exhibits a strong tendency to develop areas of carcinoma. PVL begins as a simple hyperkeratosis but tends to spread and become multifocal. PVL is slow-growing, persistent, and irreversible, and in time areas become exophytic, wartlike, and apparently resistant to all forms of therapy as recurrence is the rule. The disease was most commonly seen in elderly women and had been present for many years. Patients were followed for 1 to 20 years. Thirteen died of or with their disease, 14 were alive with PVL, and 3 were alive without PVL at last contact. PVL rarely regressed despite therapy. All patients who died had persistent or recurrent disease. PVL appears to constitute a continuum of hyperkeratotic disease, ranging from a simple hyperkeratosis at one end to invasive squamous cell carcinoma at the other. Microscopic findings are dependent upon the stage of the disease's development and the location and adequacy of the biopsy.

Papillomaviruses: their possible role in oral disease

Papillomaviruses are ubiquitous DNA viruses that are epitheliotropic and produce a range of epithelial neoplasms, both benign and malignant, in animals and man. Human papillomaviruses are associated with a variety of rare and uncommon oral lesions, and there has been increasing suspicion that they may be implicated also in some premalignant and malignant oral lesions.

Analysis of oral papillomas, leukoplakias, and invasive carcinomas for human papillomavirus type related DNA

Five papillomas, five leukoplakias, and six carcinomas were investigated for the presence of papillomavirus group-specific antigens and viral DNA. Viral proteins were identified with genus-specific papillomavirus antibodies. Cloned human papillomavirus (HPV) 11 and 16 DNA were used as probes in Southern blot hybridization at conditions of different stringency in order to determine viral DNA. Four of five papillomas, four of five leukoplakias, and three of six carcinomas reacted with HPV DNA probes and revealed some stained cells after exposure to HPV antibodies. HPV type 16 was found in one carcinoma and HPV type 11 was demonstrated in another case of carcinoma.

Verrucous carcinoma: a possible viral pathogenesis

Seventeen cases of verrucous carcinoma of the oral cavity were reviewed. It was found that cytologic features generally associated with viral modification were observed in 15 of these cases. This finding suggests that viruses may play some role in the pathogenesis of verrucous carcinoma. The hypothesis that an opportunistic, persistent virus may act in concert with frank carcinogens to promote the development of verrucous carcinoma is discussed.

Quantitative analysis of immunocompetent cells in human normal oral and uterine cervical mucosa, oral papillomas and leukoplakias

Using monoclonal antibodies reacting with T-cell subpopulations, Langerhans cells and macrophages, the number and distribution of cells of the immune system in normal oral and cervical mucosa was determined and statistically compared with that in oral papillomas and oral leukoplakias. Increased numbers of labelled cells were found in oral leukoplakias and particularly in oral papillomas. In the epithelium of all specimens, Langerhans cells and T-lymphocytes of the suppressor/cytotoxic phenotype as well as of the helper phenotype were seen. Suppressor/cytotoxic and helper T-lymphocytes were in equal numbers in the epithelium of oral papillomas, but were about 2:1 in all other lesions. In normal oral epithelium, macrophages were rare but were in greater numbers in leukoplakias and papillomas. In the connective tissue of all lesions, more labelled cells were present than in epithelium with T-lymphocytes predominant. Although Langerhans cells were rare in connective tissue, many were seen in oral papillomas.

Oral "hairy" leucoplakia in male homosexuals: evidence of association with both papillomavirus and a herpes-group virus

An outbreak of a new form of oral leucoplakia, found principally on the lateral borders of the tongue, is reported in male homosexuals in the San Francisco area. Many of the patients showed evidence of immunosuppression, and candida was often found in the lesions. The characteristic histology is similar to that of the flat wart of skin. There was immunocytochemical evidence of papillomavirus core antigen in 77% of 30 biopsy specimens, but no papillomaviruses were detected by electron microscopy in samples from 6 randomly selected patients. In 5 of these 6 patients there was evidence of a herpes-type virus. Pneumocystis carinii pneumonia has developed in 8 of 37 patients in a 33-month period. This leucoplakia may presage AIDS, may be associated with both papillomavirus and a herpes-type virus, and may offer clues to the pathogenesis of other forms of oral epithelial hyperplasia and dysplasia.