Aspartate-ß-hydroxylase and hypoxia marker expression in head and neck carcinomas: implications for HPV-associated tumors.

BACKGROUND: A proportion of head and neck carcinomas (HNSCCs) are induced by high-risk human papillomaviruses (HPVs) and are associated with better patient outcomes compared to patients with HNSCCs related to tobacco and alcohol abuse. In the microenvironment of solid tumors, including HNSCCs, oxygen levels are often reduced, and a hypoxic state is induced. This can lead to a poor treatment response and a worse patient prognosis. One of the hypoxia-responsive genes is aspartate-ß-hydroxylase (ASPH), whose activity promotes the growth, invasiveness, and metastasis of many types of solid tumors. METHODS: In our study, HNSCC samples were analyzed for the expression of ASPH and selected endogenous hypoxia markers by real-time PCR and/or multiplex fluorescence immunohistochemistry. RESULTS: Except for the EPAS1 gene, which had higher mRNA expression in the HPV-negative group of HNSCC (p < 0.05), we found no other differences in the expression of the tested genes that were related to HPV status. On the contrary, a statistically significantly higher number of cells producing ASPH (p < 0.0001), HIF1A (p < 0.0001), GLUT1 (p < 0.0001), and MMP13 (p < 0.05) proteins were detected in the HPV-positive tumor group than in the HPV-negative sample group. All the evaluated markers, except for MMP9/13, were more abundant in the tumor parenchyma than in the tumor stroma. The Cox proportional hazard models showed that increased numbers of cells with GLUT1 and HIF1A protein expression were positive prognostic markers for overall and disease-specific survival in patients independent of HPV tumor status. CONCLUSION: The study examined HNSCC samples and found that elevated ASPH and hypoxia marker proteins, typically associated with poor prognosis, may actually indicate active HPV infection, the strongest prognostic factor in HNSCC patients. In cases where HPV status is uncertain, increased expression of HIF1A and GLUT1 can serve as positive prognostic factors.

PD1+CD8+ Cells Are an Independent Prognostic Marker in Patients with Head and Neck Cancer.

Head and neck squamous cell carcinomas (HNSCCs) belong to a group of diverse tumors, which can be induced by infection with human papillomavirus (HPV) or tobacco and alcohol consumption. The viral etiology of HNSCC relates to better clinical outcomes reflecting a different immune system response. Here, we retrospectively analyzed 97 tissue samples from oral and oropharyngeal carcinomas associated and non-associated with HPV infection using multispectral fluorescent immunohistochemistry. To evaluate the immune cell infiltration in tumor and stroma compartments, we designed four panels of four to five antibodies. We detected more T lymphocytes in the stroma, compared to the tumor parenchyma. In HPV positive (HPV+) in comparison to HPV negative (HPV-) tumors, higher counts of CD3+CD4+, CD3+CD8+, PD1+CD4+, PD1+CD8+ T cells, and ICOS- Treg cells were detected while more ICOS+ Treg cells and CTLA4+CD4+ T cells were observed in HPV- than in HPV+ tumors. The results of the univariate and multivariate analyses confirmed the predominant impact of HPV status on prognosis. More importantly, the number of CD8+PD-1+ T cells was identified as an independent factor, influencing the overall and/or disease-specific survival of patients with oral cavity or oropharyngeal carcinomas.

ARG1 mRNA Level Is a Promising Prognostic Marker in Head and Neck Squamous Cell Carcinomas.

Head and neck squamous cell carcinomas (HNSCC) can be induced by smoking or alcohol consumption, but a growing part of cases relate to a persistent high-risk papillomavirus (HPV) infection. Viral etiology has a beneficial impact on the prognosis, which may be explained by a specific immune response. Tumor associated macrophages (TAMs) represent the main immune population of the tumor microenvironment with a controversial influence on the prognosis. In this study, the level, phenotype, and spatial distribution of TAMs were evaluated, and the expression of TAM-associated markers was compared in HPV positive (HPV+) and HPV negative (HPV-) tumors. Seventy-three formalin and embedded in paraffin (FFPE) tumor specimens were examined using multispectral immunohistochemistry for the detection of TAM subpopulations in the tumor parenchyma and stroma. Moreover, the mRNA expression of TAM markers was evaluated using RT-qPCR. Results were compared with respect to tumor etiology, and the prognostic significance was evaluated. In HPV- tumors, we observed more pro-tumorigenic M2 in the stroma and a non-macrophage arginase 1 (ARG1)-expressing population in both compartments. Moreover, higher mRNA expression of M2 markers-cluster of differentiation 163 (CD163), ARG1, and prostaglandin-endoperoxide synthase 2 (PTGS2)-was detected in HPV- patients, and of M1 marker nitric oxide synthase 2 (NOS2) in HPV+ group. The expression of ARG1 mRNA was revealed as a negative prognostic factor for overall survival of HNSCC patients.

Consensus recommendations from the Czech Head and Neck Cancer Cooperative Group (2019): definition of surgical margins status, neck dissection reporting, and HPV/p16 status assessment.

The Czech Head and Neck Cancer Cooperative Group (CHNCCG) held a meeting in Tabor on 11-12 October 2019 with the aim of reaching an interdisciplinary consensus on some controversial points where international unity is absent. The meeting resulted in recommendations on resection margin size terminology (definition of terms: negative margin, close margin and positive margin) and on the adoption of terminology for neck dissections reporting according to the International Recommendation of the International Head and Neck Scientific Group and on assessment of HPV/p16 status in head and neck tumors.

Prevalence and Risk Factors for Oral HPV in Healthy Population, in Central Europe.

Background/Aim: The incidence of oropharyngeal tumours induced by human papillomaviruses (HPV) is ever increasing. Information about oral HPV prevalence and its risk factors are very important for future screening and early diagnosis of the disease. The present study aimed to assess oral HPV prevalence in healthy population and risk factors for HPV infection, since this data is scarce or even missing in Central Europe. Patients and Methods: HPV prevalence in oral rinse and HPV-specific antibodies in peripheral blood were investigated in two groups of healthy participants. Group I consisted of 294 students who reached sexual maturity after the HPV vaccine had been licensed with mean age 23.2 years, and Group II of 215 unvaccinated participants with the mean age 55.7 years. Additionally, the risk factors were evaluated. Results: In Group I, 2% of participants were positive for oral HPV DNA. A statistically significantly higher rate (8.8%) was found in Group II. The seropositivity rates for anamnestic HPV antibodies were comparable in both groups. None of the analysed risk factors was significantly associated with oral HPV positivity. Conclusion: The lower prevalence of oral HPV DNA in younger participants suggests the positive influence of vaccination against oral HPV.

Otorhinolaryngology and sleep disorders.

In the field of sleep disorders, otorhinolaryngology is mainly concerned with snoring and obstructive sleep apnea (OSA). Prevalence of OSA is suggested between 14-49 % of male and 5-30 % of female population, which makes it most common sleep disorder. The treatment of choice is positive airway pressure (PAP) therapy with excellent success rate of 90 %, however many patients dont tolerate it. Sleep surgery is usually used to get off snoring and for mild cases of OSA. Most of surgical approaches has much lower effectivity than PAP therapy; however, surgery benefit is present constantly, while PAP therapy demands patients cooperation, that is why many patients still prefer sleep surgery.

Prognostic value of posttreatment HPV-specific antibodies in patients with oropharyngeal tumors.

BACKGROUND: The presence of human papillomavirus (HPV)-specific antibodies in patients with head and neck cancer at enrollment has prognostic significance. In cervical carcinoma patients, the decrease of HPV E6/E7-specific antibodies appears to be associated with a better prognosis. METHODS: This prospective study with follow-up focused on the persistence and prognostic value of antibodies specific for HR HPV-derived VLPs and HPV16 E6/E7 oncoproteins in patients with oropharyngeal cancers. In this study, we analyzed sera of 93 patients taken a year after the end of treatment and sera from 58 of these patients taken up to 14 years after treatment. RESULTS: The level of HPV-specific antibodies decreased on the 1-year follow-up and the decrease during the long follow-up was statistically significant. For HPV16 E7 antibodies the decrease was steeper in nonrecurrent patients. While the level of antibodies at enrollment was not predictive of recurrences, the decrease of HPV16 E6 antibodies at 1-year follow up was associated with better overall as well as disease-specific survival of patients. CONCLUSIONS: The data suggest that the pretreatment level of HPV-specific antibodies is not predictive of the occurrence of recurrences but the decrease HPV16 E6 antibodies on the 1-year follow-up is predictive of better survival of HN patients.

Clinical relevance of human papillomavirus outside of oropharynx.

PURPOSE OF REVIEW: The role of HPV in oropharyngeal cancer is well recognized. HPV DNA is also found in a fraction of head and neck tumors outside of oropharynx but its clinical importance is unknown. The purpose of this review is to sum up the present knowledge about the prevalence and possible impact of HPV presence in head and neck tumors in nonoropharyngeal sites. RECENT FINDINGS: The data demonstrating prevalence of HPV presence in tumors outside of oropharynx are inconsistent. However, it can be stated that it is substantially lower than in oropharynx. Most articles report the HPV DNA presence only but very few prove also the transcriptionally active viral presence. The fraction of really HPV-induced tumors is probably very small. The majority of literature shows no impact of HPV on prognosis in nonoropharyngeal locations. Also the role of high-risk HPV in malignant transformation of lesions potentially linked to malignancy like inverted papillomas, recurrent respiratory papillomatosis or laryngeal dysplasia was up to date not demonstrated. SUMMARY: Despite of the unknown role of HPV and lack of evidence regarding any clinical use of HPV knowledge in other than oropharyngeal tumors, further research is warranted.

HPV infection and P16 expression in oral and oropharyngeal cancer in Kazakhstan.

BACKGROUND: Human papillomavirus (HPV) is an important etiologic factor in different cancers of anogenital region and also in a fraction of head and neck cancers (HNC) particularly oropharyngeal tumors. The HPV16 genotype associated with the majority of HPV-related head and neck carcinomas. Th incidence of oropharyngeal cancer is increasing in many countries, and the rate of HPV positive tumors is about 70% in Europe and North America. Little known about the prevalence of HPV in HNC in Central Asia. METHODS: It's a prospective analysis of patients with verified oral or oropharyngeal cancer. Sociodemographic and clinical data obtained on admission to treatment. The diagnosis of HPV positivity assessed by both the P16 expression on immunohistochemistry(IHC) and polymerase chain reaction (PCR)with HPV DNA detection and HR HPV type determination. RESULTS: Seventy six patients with oral and oropharyngeal cancer tested for HPV. Forteen cases were positive for HPV by PCR and 15 cases by P16 IHC. Of the 35 oropharyngeal tumors, nine were HPV DNA and p16 IHC positive, giving the rate of 25.7%. Of the 41 oral tumors, five were HPV DNA and six p16 IHC positive, giving the rate of 12.2%. CONCLUSION: It is the first study mapping prevalence of HPV positivity in oral and oropharyngeal cancer in the Central Asian region. The rate of HPV positivity was higher in oropharyngeal than in oral cancer, the nonsmokers were significantly more frequent in the HPV positive group and HPV 16 was the most frequent type. However, the HPV positivity rates are lower than referred in the western world.

Comparison of the miRNA expression profiles in fresh frozen and formalin-fixed paraffin-embedded tonsillar tumors.

MicroRNAs are considered as promising prognostic and diagnostic biomarkers of human cancer since their profiles differ between tumor types. Most of the tumor profiling studies were performed on rarely available fresh frozen (FF) samples. Alternatively, archived formalin-fixed paraffin-embedded (FFPE) tissue samples are also well applicable to larger-scale retrospective miRNA profiling studies. The aim of this study was to perform systematic comparison of the miRNA expression profiles between FF and macrodissected FFPE tonsillar tumors using the TaqMan Low Density Array system, with the data processed by different software programs and two types of normalization methods. We observed a marked correlation between the miRNA expression profiles of paired FF and FFPE samples; however, only 27-38% of the differentially deregulated miRNAs overlapped between the two source systems. The comparison of the results with regard to the distinct modes of data normalization revealed an overlap in 58-67% of differentially expressed miRNAs, with no influence of the choice of software platform. Our study highlights the fact that for an accurate comparison of the miRNA expression profiles from published studies, it is important to use the same type of clinical material and to test and select the best-performing normalization method for data analysis.

Beta-HPV types in patients with head and neck pathology and in healthy subjects.

BACKGROUND: Human papillomaviruses (HPV) are a heterogeneous group of viruses classified into five genera. The beta-HPV type (beta-PV) infection is very common but mostly asymptomatic in immunocompetent individuals. However, beta-PVs play a role in Epidermodysplasia verruciformis and possibly in non-melanoma skin cancer. Head and neck cancer (HNC) is a common cancer type worldwide and high-risk alpha-PV involvement in HNC has been extensively studied but beta-PV types have rarely been the focus of such studies. OBJECTIVES: To evaluate the prevalence of beta-PV types in HNC, subjects with non-malignant or potentially pre-malignant oral lesions, and healthy controls. STUDY DESIGN: The frequency of different beta-PVs in samples from oral (n=35) and oropharyngeal (n=35) cancer patients, gender- and age-matched healthy controls (n=70), and subjects with various non-malignant or potentially pre-malignant oral lesions (n=102) was assessed by a highly sensitive, bead-based, multiplex genotyping assay. RESULTS: Overall, 54.8% of all tested samples contained at least one beta-PV type. Even though the correlation between types found in lavage and tissue specimens from cancer patients was low, there was a large statistically significant difference between oropharyngeal cancer patients and matched controls for HPV5 (P=0.003; OR=15.58) and between both oral (P=0.026; OR=5.7) and oropharyngeal cancer patients (P=0.002; OR=25.5) and controls for HPV122. In addition, there was no correlation between the prevalence of alpha and beta-PVs in the study patients. CONCLUSION: The study provides new data on the prevalence of beta-PVs in HNC. HPV5 was found significantly associated with HNC as already observed by other studies. Additionally, the significant association of HPV122 with HNC might warrant further study as this type has not been extensively studied so far.

Comparison of the miRNA profiles in HPV-positive and HPV-negative tonsillar tumors and a model system of human keratinocyte clones.

BACKGROUND: Better insights into the molecular changes involved in virus-associated and -independent head and neck cancer may advance our knowledge of HNC carcinogenesis and identify critical disease biomarkers. Here we aimed to characterize the expression profiles in a matched set of well-characterized HPV-dependent and HPV-independent tonsillar tumors and equivalent immortalized keratinocyte clones to define potential and clinically relevant biomarkers of HNC of different etiology. METHODS: Fresh frozen tonsillar cancer tissues were analyzed together with non-malignant tonsillar tissues and compared with cervical tumors and normal cervical tissues. Furthermore, relative miRNAs abundance levels of primary and immortalized human keratinocyte clones were evaluated. The global quantitation of miRNA gene abundance was performed using a TaqMan Low Density Array system. The confirmation of differentially expressed miRNAs was performed on a set of formalin-fixed paraffin-embedded tumor samples enriched for the tumor cell fraction by macrodissection. RESULTS: We defined 46 upregulated and 31 downregulated miRNAs characteristic for the HPV-positive tonsillar tumors and 42 upregulated miRNAs and 42 downregulated miRNAs characteristic for HPV-independent tumors. In comparison with the expression profiles in cervical tumors, we defined miR-141-3p, miR-15b-5p, miR-200a-3p, miR-302c-3p, and miR-9-5p as specific for HPV induced malignancies. MiR-335-5p, miR-579-3p, and miR-126-5p were shared by the expression profiles of HPV-positive tonsillar tumors and of the HPV immortalized keratinocyte clones, whereas miR-328-3p, miR-34c-3p, and miR-885-5p were shared by the miRNA profiles of HPV-negative tonsillar tumors and the HPV-negative keratinocytes. CONCLUSIONS: We identified the miRNAs characteristic for HPV-induced tumors and tonsillar tumors of different etiology, and the results were compared with those of the model system. Our report presents the basis for further investigations leading to the identification of clinically relevant diagnostic and/or therapeutic biomarkers for tumors of viral and non-viral etiology.

Analysis of the integration of human papillomaviruses in head and neck tumours in relation to patients' prognosis.

Integration, which leads to the disruption of the circular HPV genome, is considered as a critical, albeit not obligatory, step in carcinogenic progression. Although cervical carcinomas with extrachromosomal HPV plasmid genomes have been described, the virus is integrated in 70% of HPV16-positive cervical tumours. Limited information is available about HPV integration in head and neck tumours (HNC). In this study, we have characterised the physical status of HPV in a set of tonsillar tumour samples using different methods--the mapping of E2 integration breakpoint at the mRNA level, the 3' RACE based Amplification of Papillomavirus Oncogene Transcripts (APOT) assay and Southern blot. Furthermore, the impact of HPV integration on patients' prognosis has been evaluated in a larger set of 186 patients with head and neck cancer. Based on the analysis of E2 mRNA, HPV was integrated in the host genome in 43% of the HPV-positive samples. Extrachromosomal or mixed form was present in 57%. In fresh frozen samples, the APOT and E2 mapping results were in agreement. The results were confirmed using Southern blotting. Furthermore, the type and exact site of integration were determined. The survival analysis of 186 patients revealed HPV positivity, tumour size and lymph node positivity as factors that influence disease specific survival. However, no statistically significant difference was found in disease specific survival between patients with HPV-positive integrated vs. extrachromosomal/mixed forms of the virus.

What are the implications of human papillomavirus status in oropharyngeal tumors for clinical practice?

PURPOSE OF REVIEW: Human papillomavirus (HPV) status itself is an important and very probably the strongest prognostic factor in head and neck cancer. Because of the prognostic advantage of patients with HPV-positive cancers, the issue of the quality of life of survivors has become increasingly important. The possibility of treatment de-escalation in patients with virally induced tumors is being considered. Many challenges have to be addressed in order to integrate HPV status in the routine decision-making in patients with oropharyngeal cancer. The present review discusses the standardization of detection methods suitable for clinical use and the differences in predictive parameters between patients with HPV-positive and HPV-negative tumors. RECENT FINDINGS: The gold standard for the identification of patients with oropharyngeal tumors etiologically linked to HPV infection is undoubtedly the detection of HPV 16 E6/E7 mRNA. The detection of a surrogate marker of active viral infection, p16ink4a, has a low sensitivity when used alone and must therefore be combined with the detection of HPV DNA or HPV-specific antibodies. The detailed knowledge of the importance of specific prognostic parameters is crucial in the choice of treatment. Nodal staging is probably much less important in HPV-positive cancers. SUMMARY: It is of great importance to implement standardized testing for the identification of patients with HPV-induced oropharyngeal tumors. The treatment decision models in HPV-positive tumors have to take into account the probably different prognostic value of nodal parameters. Before introducing treatment de-escalation in patients with virally induced tumors into clinical practice, more research and clinical studies are needed.

Markers of HPV infection and survival in patients with head and neck tumors.

The purpose of this study was to determine whether changes in human papillomavirus (HPV) DNA prevalence in oral rinses and/or HPV-specific antibody levels in the sera of patients with oral/oropharyngeal cancer have prognostic significance. One hundred and forty-two patients with oral/oropharyngeal tumors were enrolled. The presence of HPV DNA was assayed in tumor tissue and oral rinses and HPV-specific antibodies were assessed in the sera. Oral rinses were collected before treatment and one year after the treatment. Sera were drawn before treatment, one month, and one year after the end of the treatment. Altogether, 59.2% of tumors were HPV positive. The presence of HPV DNA in the tumors correlated with HPV DNA positivity in oral rinses and with HPV-specific antibodies in the sera. Out of 66 patients with HPV-positive oral rinses at enrolment, 84.8% became negative at one-year follow-up, while most patients remained seropositive for HPV-specific antigens. However, the mean titers of HPV16 E6 and/or E7 antibodies at follow-up were significantly lower. Of 16 patients with recurrences at follow-up (alive on second sampling), six were positive at enrolment for HPV16 E6 and/or E7 antibodies. In five of these, no decrease in antibody levels was observed. Titers of antibodies specific for HPV16 capsid antigens did not change during the follow-up. Our data suggest that the detection of antibodies specific for the HPV 16 E6 and E7 oncoproteins may serve not only as a marker of HPV etiology, but also as a marker of recurrence and a prognostic indicator in patients with HPV-positive tumors.

Nodal status is not a prognostic factor in patients with HPV-positive oral/oropharyngeal tumors.

OBJECTIVES: The primary aim is to compare the prognostic parameters in patients with HPV-positive and HPV-negative tumors. The secondary aim is to compare the patterns of treatment failure between these groups. METHODS: Analysis of prognostic factors in a group of 170 patients. RESULTS: High-risk HPV DNA was detected in 98 cases, 72 tumors were HPV negative. Both the overall and disease-specific survival rates were better in HPV-positive patients. In patients with HPV-negative tumors, the prognostic factors in univariate analysis were pT and pN classification, tumor stage, number of positive nodes, and extracapsular spread. Stage, pT, higher pN, and number of nodes maintained statistical significance after adjustment. None of the studied prognostic factors was significant in the group of patients with HPV-positive tumors. There was a significant difference in the local--regional recurrence rates--37% in HPV-negative cases and 18% in HPV-positive cases. CONCLUSION: The characteristics of the extent of the disease in general and of regional lymph node metastasis in particular are probably much less important in the prediction of the outcome of HPV-positive than of HPV-negative tumors. Improved survival of patients with HPV-positive tumors is due mostly to the difference in the local-regional failure rates.

Combined bipolar radiofrequency surgery of the tongue base and uvulopalatopharyngoplasty for obstructive sleep apnea.

INTRODUCTION: The aim of the study was to investigate the effectiveness of combined bipolar radiofrequency surgery of the tongue base (RFBT) and uvulopalatopharyngoplasty (UPPP) in a single session for obstructive sleep apnea and whether this combination is safe and well tolerated. MATERIAL AND METHODS: Seventy-nine patients with obstructive sleep apnea and both palatal and retroglossal obstruction underwent UPPP with bipolar RFBT. The control group consisted of 35 patients treated by UPPP alone. RESULTS: The apnea-hypopnea index significantly decreased from 28.7 to 14.1. The oxygen desaturation index decreased from 15.1 to 10.3. Mean oxygen saturation was unchanged. Subjectively, the Epworth Sleepiness Scale was significantly improved from 10.6 to 7.3, and the snoring level decreased from 8.4 to 6.0. The overall treatment success rate increased from 41.9% for UPPP alone to 51.7% for UPPP + RFBT. No serious adverse events occurred. Two patients had postoperative bleeding from the tonsillar bed after UPPP. Four patients had ulceration of the base of the tongue after RFBT with spontaneous cure. One patient had a taste change in half of the tongue that resolved within two months. CONCLUSIONS: Combined bipolar RFBT and UPPP in a single session is well tolerated and safe surgery in the treatment of obstructive sleep apnea. It is effective in reducing respiratory parameters and subjective symptoms of obstructive sleep apnea. Further advantages are a single session, simple feasibility, bipolar technique and short time of the procedure.

Complications of total laryngectomy in the era of chemoradiation.

As more total laryngectomies (TLE) are nowadays performed as salvage procedures, the rate of postoperative complications increases. The primary aim was to report the rates of postoperative local complications for total laryngectomy in patients with previous radiotherapy or chemoradiotherapy (RT/CRT) in comparison with primary TLE data. We attempted to identify patient- and tumor-related factors predictive of postoperative pharyngocutaneous fistula (PCF) formation. The secondary aims were to analyze the survival rate in relation to postoperative complications and to study prognostic factors of survival in TLE patients. A retrospective study was conducted in 208 patients. Logistic regression was used to determine the most significant risk factors for fistula formation. Survival was analyzed by the Kaplan-Meier method, log-rank test, and Cox multivariate regression. PCF developed in 20.7% of cases. In the group of patients with previous RT/CRT, the fistula rate was significantly higher (34%). In multivariate analysis, significant risk factors for fistula formation were previous radiotherapy or chemoradiotherapy (p = 0.02), higher N classification (p = 0.03), and procedure performed by a less experienced surgeon (p = 0.003). The survival and recurrence rates were not influenced by PCF formation. The overall survival rates were lower in patients with previous RT/CRT and in patients with lymph node involvement.

HPV involvement in tonsillar cancer: prognostic significance and clinically relevant markers.

The association of high-risk human papillomaviruses (HR HPVs) with tonsillar cancer (TC) has been documented. Because patients with HPV-associated tumors show better survival rates, modification of their treatment regimen is being considered. It is therefore crucial to find markers for the identification of patients whose tumors are linked to viral infection. A cohort of 109 patients with primary TC was screened for HPV DNA presence in the tumor tissues and HPV-specific antibodies in sera. Data regarding risk factors and clinical parameters were collected. Forty-five specimens were analyzed for the expression of viral E6 and E2-region mRNA, and the p16 and p53 protein expression status was assessed by immunohistochemistry. The overall prevalence of HPV DNA in TC tissues was 65.1%. Ninety-three percent of HR HPV DNA-positive samples expressed E6*I mRNA. E2-region mRNA expression was detected in 36% of positive samples, which implies that the virus is integrated in 64% of HPV DNA/RNA-positive tumors. p16 overexpression and the presence of antibodies specific to HPV16 E6/E7 oncoproteins correlated well with HPV DNA and RNA presence. The disease-specific survival rate of patients with HPV DNA-positive tumors was significantly higher than that of HPV DNA-negative patients. In addition to providing further evidence of the involvement of HPV infection in the etiopathogenesis of a proportion of TC cases, our study demonstrates that p16 immunostaining and anti-E6/E7 antibodies as surrogate markers of HPV involvement represent specific, sensitive and clinically accessible assays for the identification of TC patients who have a considerably better prognosis.

Human papillomavirus in head and neck tumors: epidemiological, molecular and clinical aspects.

High-risk types of human papillomaviruses (HR HPV) play an important role in the etiology of a group of head and neck squamous cell cancers (HNSCC). This review is focused on epidemiological, molecular, and clinical aspects of HPV infection in head and neck cancer. High risk HPV DNA is being detected in a very different proportion of HNSCC with the highest prevalence in oropharynx. Patients with HPV-associated tumors are characterized by moderate tobacco and alcohol consumption. Some aspects of sexual behavior may represent a risk factor. Recently, it has been shown that HPV infection is spreading and the rising prevalence of HPV-positive tumors can probably be attributed to this epidemic. On molecular level the viral oncoproteins E6 and E7 were shown to be involved in oncogenesis. HPV-positive cancers have better prognosis and HPV status should be considered in clinical decision-making. The rising proportion of HPV-positive tumors underlines the importance of HPV vaccination also for the prevention of HNSCC.