High risk human papillomavirus in oral squamous carcinoma: evidence of risk factors in a Venezuelan rural population. Preliminary report

Human papillomavirus prevalence in oral and oropharyngeal squamous cell carcinoma in South America

Some studies have addressed the prevalence of human papillomavirus (HPV) in head and neck cancer in South America; however, no studies have systematically gathered prevalence and conducted a meta-analysis. This study aims to estimate the prevalence of HPV in oral and oropharyngeal squamous cell carcinomas in South America. We performed a systematic review and metaanalysis using the following databases: PubMed, Embase, Lilacs, Medline, Scopus, and Web of Science. Data were extracted and analyzed using random-effects models to estimate the pooled prevalence of HPV. We identified 209 nonduplicated studies, of which 38 were selected. The overall prevalence of HPV was 24.31% (95% CI 16.87–32.64; I² = 96%, p_{heterogeneity} <0.001). HPV prevalence in oropharyngeal cancer was 17.9% (95% CI 7.6–31.4; I² = 96%, p_{heterogeneity} <0.001) and that in oral cavity cancer was 23.19% (95% CI 14.94–32.63; I² = 94%, p_{heterogeneity} <0.001). We found an overall prevalence of HPV in 24.31% of oral and oropharyngeal squamous cell carcinomas in South American patients. The prevalence of HPV was 17.9% for oropharyngeal cancer and 23.19% for oral cavity cancer.

Molecular Identification of Human Papillomavirus DNA in Thyroid Neoplasms: Association or Serendipity?

Background: Human papillomavirus (HPV) is recognized as the most important cofactor in the etiology of cancers of the cervix, esophagus, larynx, and nasopharynx. Experimental evidence suggests that HPV could have an oncogenic influence on thyroid follicular cells; however, to the best of our knowledge, there is no record of its role in human thyroid gland neoplasms.

Objective: The purpose of this study is to describe the frequency and the types of HPV present in neoplastic thyroid tissue by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP).

Methods: Over 157 samples were analyzed of paraffin-embedded tissue from malignant and benign thyroid tumors. All the paraffin blocks were selected consecutively from the Pathology Tissue Bank archive of the Western Medical Center. The molecular detection and typing were performed at the Molecular Microbiology Laboratory of the Biomedical Research Center, Mexican Institute of Social Security.

Results: The frequency of HPV findings was 2.5% (four cases). HPV-6 was found in two cases of thyroid hyperplasia (2.5%), and HPV-33 in two cases of papillary cancer (4.6%).

Conclusion: The presence of HPV is not frequent in thyroid neoplasms, at least in the studied population. Due to the low prevalence of this virus in our sample, it is not possible to reach conclusions. Further research is needed.

Detection of human papilloma virus-E6/E7 proteins of high-risk human papilloma virus in saliva and lesional tissue of oral squamous cell carcinoma patients using nested multiplex polymerase chain reaction: A comparative study

INTRODUCTION

Human papilloma virus (HPV)-associated oral squamous cell carcinoma (OSCC) shows different biological behavior as compared to tobacco-induced OSCC. Mere presence of HPV in OSCC is of no clinical significance; however, the integration of HPV-DNA through E6/E7 gene into the host genome is important as it affects the development and progression of OSCC.

AIM

The aim of this study was to determine the presence of E6/E7 proteins of high-risk (HR) HPV (HPV16 and HPV18) in saliva as well as lesional tissue of OSCC patients and to determine the use of saliva as an alternative to tissue for E6 and E7 proteins in OSCC.

MATERIALS AND METHODS

Histopathologically confirmed 47 cases of OSCC were taken up for the study. The tumor tissue and saliva sample of each patient were obtained to detect the presence of HPV16 and HPV18 along with E6/E7 proteins in both samples by nested multiplex polymerase chain reaction (NMPCR). The data were analyzed using Student t-test (2 tailed) and Wilcoxon signed-ranks test.

RESULTS

In tumor tissue, 40.42% of cases showed HPV16 (19/47) positivity while 34.04% were HPV18 (16/47) positive; whereas, in salivary sample, 31.91% showed HPV16 (15/47) positivity while 25.53% of cases were HPV18 positive (12/47). Mean age of participants was 46.7 years, males showed no significant difference from females in the prevalence of HPV 16/18 with tongue being the most common site for the occurrence. There was no statistically significant difference for HPV16/18 presence in tissue and saliva sample of OSCC. Taking lesional tissue sample as standard, sensitivity and specificity for HPV16 and HPV18 in saliva by NMPCR was estimated at 68.42% and 92.86%, respectively. The accuracy level of NMPCR detection for HPV16 was 82.98% and HPV18 was 65.96%.

CONCLUSION

The study revealed no significant difference in the prevalence of HPV (16/18) among tissue and saliva of OSCC patients in Indian population. The study also found no difference in the level of DNA content of HPV in saliva and tissue indicating that saliva can be used as an alternative predictor of HPV positivity in OSCC.

Human papillomavirus and cancerous diseases of the head and neck: a systematic review and meta-analysis

The increasing incidence of head and neck cancer (HNSCC) highlights the need to better understand the role of human papillomavirus (HPV) in the development of these cancers. The aims of this study were to conduct a systematic review and a meta-analysis concerning observational studies on the association between HPV infection and HNSCC and to quantify this association, thereby obtaining a reliable estimation of the risk of HPV infection in the development of head and neck cancer. Literature searches were performed using PubMed and Scopus databases. StatsDirect 2.7.8 program was used for the analysis. We found 15 case-control studies, 63 prevalence studies, and no cohort studies. The pooled odds ratio (OR) for all the included case-control studies resulted in a value of 1.63 (95% CI 1.27-2.09; P < 0.0001). The highest pooled OR resulted from the analysis of all the studies that examined HPV 16 genotype in association oral cavity (OR 5.36; 95% CI 1.4-20). The strong evidence of association between HPV infection and HNSCC highlights the importance of the introduction of specific tests in the cancer prevention practices to evaluate the presence of the virus, especially in the oral cavity, and the possibility of an extension of the vaccine anti-HPV in the male population too.

Evidences suggesting involvement of viruses in oral squamous cell carcinoma

Oral cancer is one of the most common cancers and it constitutes a major health problem particularly in developing countries. Oral squamous cell carcinoma (OSCC) represents the most frequent of all oral neoplasms. Several risk factors have been well characterized to be associated with OSCC with substantial evidences. The etiology of OSCC is complex and involves many factors. The most clearly defined potential factors are smoking and alcohol, which substantially increase the risk of OSCC. However, despite this clear association, a substantial proportion of patients develop OSCC without exposure to them, emphasizing the role of other risk factors such as genetic susceptibility and oncogenic viruses. Some viruses are strongly associated with OSCC while the association of others is less frequent and may depend on cofactors for their carcinogenic effects. Therefore, the exact role of viruses must be evaluated with care in order to improve the diagnosis and treatment of OSCC. Although a viral association within a subset of OSCC has been shown, the molecular and histopathological characteristics of these tumors have yet to be clearly defined.

Epidemiology of human papillomavirus-related head and neck cancer

Human papillomavirus (HPV) is now recognized to cause a subset of head and neck squamous cell carcinomas (HNSCC). Although excessive tobacco and alcohol use continue to be important risk factors for HNSCC, epidemiologic studies suggest that more than 25% of HNSCC are now caused by HPV. The incidence of HPV-related HNSCC is increasing, highlighting the need to understand the oral HPV infections causing these cancers. This article reviews the evidence for a causal association between HPV and HNSCC, examines the changing epidemiologic trends of HNSCC, and discusses what is currently known about oral HPV infection, natural history, and transmission.

Human papillomavirus (HPV) detection in lip squamous cell carcinoma: correlation with clinical aspects and risk factors

Human papillomavirus (HPV) is associated with a wide spectrum of lesions in humans, and it has been linked to oral carcinogenesis. The aim of this study was to investigate the presence of HPV DNA in patients with lip squamous cell carcinoma and to correlate it with clinical characteristics and risk factors. We studied 33 patients with lip squamous cell carcinomas. Of these, 30 were positive for human beta globin gene and tested for HPV DNA, using polymerase chain reaction in two steps (PCR and nPCR) with MY11/MY09 and GP5+/GP6+ primers. HPV DNA was detected in 43.33% of patients analyzed. There was no association with the risk factors analyzed.

Human papillomavirus in oral squamous cells carcinoma in a population of 75 Brazilian patients

PURPOSE

In the present study, we investigated the presence of human papillomavirus (HPV) DNA and viral types in 75 cases of oral squamous cells carcinoma from Brazil to obtain data that would contribute to a better understanding of the role of HPV in the pathogenesis of this tumor.

MATERIALS AND METHODS

DNA was extracted from paraffin-embedded tissue and amplified by polymerase chain reaction using a pair of primers designated PCO3+ and PCO4+ for the detection of a fragment of the human beta-globin gene, followed by polymerase chain reaction for the detection of HPV DNA using a pair of generic primers, GP5+ and GP6+. Viral typing was performed by dot blot hybridization.

RESULTS

Human papillomavirus DNA was detected in 18 (24%) of the 75 cases positive for the human beta-globin gene. No significant association was observed between HPV and age, sex, or anatomical location of the tumor. The most prevalent viral type was HPV-18 (77,8%).

CONCLUSION

The low frequency of detection of HPV DNA in oral epidermoid carcinomas suggests a possible participation of the virus in the development and progression of only a subgroup of these tumors.

Human papillomaviruses in oral squamous cell carcinoma and pre-cancerous lesions detected by PCR-based gene-chip array

Human papillomavirus (HPV) infection is a significant risk factor for uterine cervical carcinoma. Many studies have also demonstrated the presence of HPV in oral epithelia tissue, but the role of HPV infection in oral squamous cell carcinoma (OSCC) is still controversial. The aim of this study was to determine the frequency and type of HPV in OSCC and oral pre-cancerous lesions. DNA samples were collected by cytobrushing from 51 patients with OSCC, 46 with oral pre-cancerous lesions and 90 normal controls. Nested polymerase chain reaction and gene-chip arrays were used to identify the HPV types in the samples. In pre-cancerous lesions, there was a higher frequency of HPV of any type (14/46, OR = 2.844, CI = 1.186-6.816, P = 0.0216) and of low-risk HPV types (9/46, OR = 5.529, CI = 1.597-19.14, P = 0.0096) than in control samples. The prevalence of high-risk types was significantly higher in OSCC than in control lesions (11/51 vs 8/90, OR = 2.819, CI = 1.051-7.558, P = 0.0420) but this was not the case for HPV of any type (13/51 vs 12/90, OR = 2.244, CI = 0.9266-5.337, P = 0.1066). High-risk HPV types are prevalent in OSCC and may play a role in its progression, while low-risk types are associated with oral pre-cancerous lesions.

HPV in oral squamous cell carcinomas of a Brazilian population: amplification by PCR

Human Papilomaviruses (HPV) are a group of viruses associated with benign and malignant lesions of cutaneous and mucosal epithelia. Some "high risk" HPV types, especially HPV 16 and 18, are strongly correlated with cervical and anogenital cancers and are also related to the genesis of oral squamous cell carcinomas (OSCC). The aim of this work was to investigate the incidence of HPV infection in 40 paraffin-embedded or fresh specimens of OSCC, using PCR amplification of the viral DNA. Literature based primers (GP5+/GP6+) were used in order to amplify HPV DNA from the L1 gene, present in more than 22 types of HPV. A condyloma case with HPV 16 and 18 detected by in situ hybridization was used as a positive control. Amplification of HPV was observed only in the positive control. No squamous cell carcinoma cases showed DNA viral amplification. Absence of HPV DNA amplification by PCR in the analyzed specimens of OSCCs suggests that this virus not always plays a role in the carcinogenesis process. Discrepancy with some studies found in the literature may be related to methodology or population differences.

Comparative study of HPV prevalence in Japanese and North-east Chinese oral carcinoma

BACKGROUND

Human papillomavirus (HPV) plays a role in the development of oral carcinoma. However, the reported prevalence of HPV in oral carcinoma has varied widely.

METHODS

The prevalence of HPV 16, 18 and 33 was investigated in Japanese and North-east Chinese oral squamous cell carcinomas (OSCCs) with polymerase chain reaction (PCR). The expression of p53 protein was examined immunohistochemically.

RESULTS

HPV 16 and 18 were detected in 7 (23.3%) and 10 (33.3%) of 30 Japanese and 11 (36.7%) and 5 (16.7%) of 30 Chinese samples, respectively. HPV 16 and 18 coinfection was detected in 3/30 Japanese and 2/30 Chinese samples. HPV 33 was not detected. There was no significant correlation between HPV 16 and 18 and the sites, gender, age and histological grade. The prevalence of both HPV 16 and 18 was similar and higher in the Japanese and North-east Chinese samples (46.7% each). HPV 16 or/and 18 infection or/and p53 overexpression were in 22 (73.3%) of 30 Japanese samples and 24 (80.0%) of 30 North-east Chinese samples, respectively.

CONCLUSIONS

HPV 16/18 infection or/and p53 overexpression may play an important role in developing some OSCCs. and the presence of HPV sequences and mutant p53 are not necessarily mutually exclusive.

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.