p16(INK4A) genetic and epigenetic profiles differ in relation to age and site in head and neck squamous cell carcinomas. Hum Pathol. 2008;39:452-458. [PMID: 18261630 DOI: 10.1016/j.humpath.2007.08.004]

Human Papillomavirus-Associated Oral Epithelial Dysplasia: A Practical Approach to Make the Diagnosis

Background

High-risk Human Papillomavirus (HPV) genotypes are found in malignant oral epithelial lesions, and HPV infection is proposed as a risk factor for initiating Squamous cell carcinoma (SCC) in the head and neck region. This study suggests a practical approach to detect HPV in HPV-associated oral epithelial dysplasia (HAOED).

Methods

Fifty-four oral epithelial dysplasia specimens were examined, comprising twenty-seven cases diagnosed with high-grade dysplasia and twenty-seven cases diagnosed with low-grade dysplasia using a binary grading system. To assess the cases for HPV, the specimens were examined for p16 protein using an immunohistochemical (IHC) study, and then, the Chromatin In Situ Hybridization (CISH) test was performed for all positive cases. Chromatin Immunoprecipitation-Polymerase Chain Reaction (ChIP-PCR) was performed on CISH-positive specimens to assess the outcome. This cross-sectional study was conducted in 2020 at Tehran University of Medical Science. SPSS software version 22.0 was used to perform the Chi square or Fisher's exact test to examine the relationship between variables (statistically significant level P<0.05).

Results

The expression of p16 protein was not associated with the severity of epithelial dysplasia (81.5% in low-grade and 59.2% in high-grade cases) (P=0.16). Moreover, according to the CISH test result, 9.25% of all specimens were positive (P>0.99), and in the nine cases, undergone the ChIP-PCR study, two cases (22.2%) showed positivity for HPV-16, while one case (11.1%) demonstrated positivity for HPV-51.

Conclusion

Regarding HAOED, here, we proposed a step-by-step combination approach using different diagnostic methods, including IHC for p16 protein, CISH, and ChIP-PCR based on a complementary algorithm.

Recurrence in Oral Squamous Cell Carcinoma Associated with Wide Field of Cancerization: Analysis of 93 Cases

Background

The late presentation of oral squamous cell carcinoma (OSCC) patients in the Sudan, with advanced stages and wide field of cancerization, have a negative impact on both the morbidity and the mortality of these patients. The present study aimed to investigate the clinicopathological behavior of OSCC and predictors of development of recurrence in these patients.

Methods

This a prospective longitudinal study of 93 OSCC patients surgically treated at Khartoum Teaching Dental Hospital. Tumor's associated field of cancerization was identified. The patients were followed clinically on regular basis, for a year, for the development of recurrence.

Results

Out of the 93 patients, 57 (61.3%) were males and 36 (38.7%) were females. 82% of the patients presented with stage IV tumors, and 58 (62.4%) of the cases had nodal metastasis. Twenty-eight (30%) patients developed recurrence. Of them 17 (18.3%) had regional recurrence, eight (8.6%) had local recurrence and three (3.2%) had locoregional recurrence. Multivariate cox regression analysis showed that Toombak dipping (P.value = 0.001), tumor staging (P.value = 0.039) and presence of mucosal filed changes (P.value = 0.001) were independent predictors for local recurrence and positive pathological lymph nodes (P.value = 0.00) and extranodal extension (P.value = 0.040) were independent predictors for regional recurrence.

Conclusion

The present study showed that OSCC patients in the Sudan present with advanced lesions, mostly associated with wide field of cancerization particularly Toombak dippers. Overall recurrences were identified in 30% of the cases, regional recurrence was the commonest type followed by local recurrence.

A Case of HPV-Associated Oropharyngeal Squamous Cell Carcinoma with Block-Like, Partial Loss of p16 Expression

BACKGROUND

Oropharyngeal squamous cell carcinoma is frequently associated with high-risk HPV infection, which confers a good prognosis. Immunohistochemistry for p16 is used as a surrogate for HPV status, but discrepant results are occasionally seen. Here, we report a case with a unique pattern of partial loss of p16.

METHODS

A 63 year old male presented with a base of tongue nonkeratinizing squamous cell carcinoma and a large metastatic neck mass. The primary lesion and multiple regions of the metastatic mass were assessed with p16 immunohistochemistry, RNA in situ hybridization for high-risk HPV, and HPV16 genome sequencing.

RESULTS

The primary lesion was p16 negative, and the metastatic neck mass had large, confluent regions that were either strongly p16 positive or entirely p16 negative. All of these regions were positive for high-risk HPV with identical HPV16 genomes.

CONCLUSION

This unusual case illustrates a potential diagnostic pitfall, and it raises important questions regarding molecular mechanisms and prognostic implications of p16 staining in oropharyngeal squamous cell carcinoma.

Age-specific oncogenic pathways in head and neck squamous cell carcinoma - are elderly a different subcategory?

BACKGROUND

In recent clinical practice, an increasing number of elderly patients suffering from head and neck squamous cell carcinoma (HNSCC) of unknown pathophysiology is observed. The majority of HNSCC patients can roughly be divided into three subcategories. First, a small group of young patients who present with variants of genomic aberrations and inheritable diseases like Fanconi anaemia. Second, an increasing population of HPV-related HNSCCs that are regarded as genomic stable tumours with a more favourable prognosis. Though HPV-related tumours used to be more common among younger males, a notable rise in the elderly population is observed. The third subcategory, that of HPV-negative tumours, has been shown to be more heterogeneous with involvement of a variety of oncogenic pathways related to lifestyle factors like smoking and alcohol consumption, often seen in middle-aged males. Some of these pathways could be related to age, such as TP53 alterations, EGFR activation, apoptotic pathway alterations and field cancerization.

CONCLUSIONS

In this narrative review, we provide an overview of established and newly discovered age-specific pathophysiological mechanisms underlying HNSCC. We propose a fourth subcategory of patients with a suspected different pathophysiology: elderly (HPV-negative) HNSCC patients without a history of tobacco and alcohol consumption. In this subcategory, carcinogenesis seems to be a multi-step process based on genomic instability, immunosenescence, cell cycle disruption and telomere shortening. To conclude, we discuss suggestions for future research to fill the knowledge gap about age-dependent HNSCC carcinogenesis.

Portrait of DNA methylated genes predictive of poor prognosis in head and neck cancer and the implication for targeted therapy

In addition to chronic infection with human papilloma virus (HPV) and exposure to environmental carcinogens, genetic and epigenetic factors act as major risk factors for head and neck cancer (HNC) development and progression. Here, we conducted a systematic review in order to assess whether DNA hypermethylated genes are predictive of high risk of developing HNC and/or impact on survival and outcomes in non-HPV/non-tobacco/non-alcohol associated HNC. We identified 85 studies covering 32,187 subjects where the relationship between DNA methylation, risk factors and survival outcomes were addressed. Changes in DNA hypermethylation were identified for 120 genes. Interactome analysis revealed enrichment in complex regulatory pathways that coordinate cell cycle progression (CCNA1, SFN, ATM, GADD45A, CDK2NA, TP53, RB1 and RASSF1). However, not all these genes showed significant statistical association with alcohol consumption, tobacco and/or HPV infection in the multivariate analysis. Genes with the most robust HNC risk association included TIMP3, DCC, DAPK, CDH1, CCNA1, MGMT, P16, MINT31, CD44, RARβ. From these candidates, we further validated CD44 at translational level in an independent cohort of 100 patients with tongue cancer followed-up beyond 10 years. CD44 expression was associated with high-risk of tumor recurrence and metastasis (P = 0.01) in HPV-cases. In summary, genes regulated by methylation play a modulatory function in HNC susceptibility and it represent a critical therapeutic target to manage patients with advanced disease.

The Pathologic and Molecular Landscape of Esophageal Squamous Cell Carcinogenesis

Esophageal squamous cell carcinoma represents the most common histotype of epithelial neoplasm occurring within esophageal mucosa worldwide. Despite the comprehensive molecular characterization of this entity, to date no significant targeted therapy has been introduced into clinical practice. In this review, we describe the molecular landscape of esophageal squamous cell carcinoma based on the most recent literature. Moreover, we focus on other rare variants and on the relationship with head and neck squamous cell carcinomas.

DNA Methylation Changes in Human Papillomavirus-Driven Head and Neck Cancers

Disruption of DNA methylation patterns is one of the hallmarks of cancer. Similar to other cancer types, human papillomavirus (HPV)-driven head and neck cancer (HNC) also reveals alterations in its methylation profile. The intrinsic ability of HPV oncoproteins E6 and E7 to interfere with DNA methyltransferase activity contributes to these methylation changes. There are many genes that have been reported to be differentially methylated in HPV-driven HNC. Some of these genes are involved in major cellular pathways, indicating that DNA methylation, at least in certain instances, may contribute to the development and progression of HPV-driven HNC. Furthermore, the HPV genome itself becomes a target of the cellular DNA methylation machinery. Some of these methylation changes appearing in the viral long control region (LCR) may contribute to uncontrolled oncoprotein expression, leading to carcinogenesis. Consistent with these observations, demethylation therapy appears to have significant effects on HPV-driven HNC. This review article comprehensively summarizes DNA methylation changes and their diagnostic and therapeutic indications in HPV-driven HNC.

Frequency of HPV in oral cavity squamous cell carcinoma

BACKGROUND

The prevalence of high-risk human papillomavirus (HPV) DNA in cases of oral cavity squamous cell carcinoma (SCC) varies widely. The aim of this study is to investigate the frequency of high-risk HPV DNA in a large Brazilian cohort of patients with oral cavity SCC.

METHODS

Biopsy and resected frozen and formalin-fixed paraffin-embedded specimens of oral cavity SCC were available from 101 patients who were recruited at two Brazilian centres. Stringent measures with respect to case selection and prevention of sample contamination were adopted to ensure reliability of the data. Nested PCR using MY09/MY11 and GP5⁺/GP6⁺ as well as PGMY09/11 L1 consensus primers were performed to investigate the presence of HPV DNA in the tumours. HPV-positive cases were subjected to direct sequencing. Shapiro-Wilk and Student t test were used to evaluate data normality and to compare the means, respectively. Qualitative variables were analysed by logistic regression.

RESULTS

Our results demonstrate that the frequency of high-risk HPV types in oral cavity SCC is very low and is less than 4%. All HPV-positive cases were HPV16. In addition, our results do not show a significant association between the tumour clinical features and the risk factors (tobacco, alcohol and HPV) for oral cavity SCC.

CONCLUSION

In the current study, we observed an overlapping pattern of risk factors that are related to tumour development. This, along with a low frequency of high-risk HPV DNA, supports the findings that HPV is not involved in the genesis of oral cavity SCC in Brazilian population.

Novel insights into epigenetic drivers of oropharyngeal squamous cell carcinoma: role of HPV and lifestyle factors

In the last years, the explosion of high throughput sequencing technologies has enabled epigenome-wide analyses, allowing a more comprehensive overview of the oropharyngeal squamous cell carcinoma (OPSCC) epigenetic landscape. In this setting, the cellular pathways contributing to the neoplastic phenotype, including cell cycle regulation, cell signaling, DNA repair, and apoptosis have been demonstrated to be potential targets of epigenetic alterations in OPSCC. Of note, it has becoming increasingly clear that HPV infection and OPSCC lifestyle risk factors differently drive the epigenetic machinery in cancer cells. Epigenetic changes, including DNA methylation, histone modifications, and non-coding RNA expression, can be used as powerful and reliable tools for early diagnosis of OPSCC patients and improve prognostication. Since epigenetic changes are dynamic and reversible, epigenetic enzymes may also represent suitable targets for the development of more effective OPSCC therapeutic strategies. Thus, this review will focus on the main known epigenetic modifications that can occur in OPSCC and their exploitation as potential biomarkers and therapeutic targets. Furthermore, we will address epigenetic alterations to OPSCC risk factors, with a particular focus on HPV infection, tobacco exposure, and heavy alcohol consumption.

Frequent promoter hypermethylation associated with human papillomavirus infection in pharyngeal cancer

Oropharyngeal squamous cell carcinoma (OPSCC) incidence has increased dramatically due to human papillomavirus (HPV); however, associated epigenetic alterations are not well studied. We performed genome-wide DNA methylation analysis using an Infinium 450k BeadArray for clinical OPSCC and non-cancerous samples and cancer cell lines with/without 5-aza-2'-deoxycytidine and/or trichostatin A treatment. Frequent promoter hypermethylation and methylation-associated silencing were detected in 144 genes, which included those involved in cell-cell signaling and neuron differentiation. The methylation of nine genes (GHSR, ITGA4, RXRG, UTF1, CDH8, FAN19A4, CTNNA2, NEFH, and CASR) was quantitatively validated in 70 pharyngeal SCC cases by pyrosequencing. Hypermethylation significantly correlated with HPV-L1 positivity, but not with age or smoking status. p16^INK4A was generally activated in HPV-L1(+) tumors, and p16-positive cases significantly associated with better prognosis. RXRG hypermethylation strongly correlated with positivity of HPV-L1 and p16 (P = 3 × 10^-5 and P = 5 × 10^-4, respectively). RXRG-methylation(+) significantly associated with better prognosis when analyzing all tumor cases (P = 0.04), and when analyzing the p16-negative poorer-outcome group (P = 0.03). Thus, aberrant DNA methylation might be involved in HPV-associated OPSCC; in addition, DNA methylation could serve as a marker to classify subgroups based on outcome.

Human papillomavirus and head and neck carcinomas: focus on evidence in the babel of published data

Human papillomavirus (HPV)-associated squamous cell carcinoma of the oropharynx is a well-defined entity mostly affecting young to middle-aged male non-smokers. It is generally associated with a favourable outcome, and for this reason a less intensive therapeutic approach has been proposed for this subset of patients. The incidence of HPV-associated oropharyngeal cancers is rapidly increasing in most Western countries, but detailed epidemiological data are not available for the Italian population. Furthermore, among other head and neck regions, a smaller proportion of oral high-grade dysplasia and cancers seems to depend on HPV infection, whereas its role in laryngeal cancer is recognised as less relevant. HPV-dependent neoplastic transformation depends on the expression of viral oncogenes in the infected host cell that can only be directly documented through viral oncogene mRNA identification. The consensus on how to classify these patients from clinical and laboratory diagnostic points of view is still limited, with different approaches based on one or more diagnostic techniques including p16 immunostaining, in situ hybridisation and polymerase chain reation (PCR) amplification of viral DNA. The possibility of early diagnosis relying on the identification of HPV infection in oral and oropharyngeal exfoliated cells has so far provided unsatisfactory results, although viral persistence after treatment has been associated with risk of recurrence. Presently, sufficient data are not available to document the natural history and progression from tonsillar HPV infection to oropharyngeal cancer development, and to clearly define the modality of transmission and risk exposure, among which sexual behaviours appear to play a relevant role. The diffusion of HPV vaccination and its administration to both genders will undoubtedly dramatically modify the epidemiology of HPV-related head and neck cancers in the coming years.

Phospho-T356RB1 predicts survival in HPV-negative squamous cell carcinoma of the head and neck

Locally advanced squamous cell carcinoma of the head and neck (SCCHN) that is not associated with human papillomavirus (HPV) has a poor prognosis in contrast to HPV-positive disease. To better understand the importance of RB1 activity in HPV-negative SCCHN, we investigated the prognostic value of inhibitory CDK4/6 phosphorylation of RB1 on threonine 356 (T³⁵⁶) in archival HPV-negative tumor specimens from patients who underwent surgical resection and adjuvant radiation. We benchmarked p^T356RB1 to total RB1, Ki67, p^T202/Y204ERK1/2, and TP53, as quantified by automatic quantitative analysis (AQUA), and correlated protein expression with tumor stage and grade. High expression of p^T356RB1 but not total RB1 predicted reduced overall survival (OS; P = 0.0295), indicating the potential relevance of post-translational phosphorylation. Paired analysis of The Cancer Genome Atlas (TCGA) data for regulators of this RB1 phosphorylation identified loss or truncating mutation of negative regulator CDKN2A (p16) and elevated expression of the CDK4/6 activator CCND1 (cyclin D) as also predicting poor survival. Given that CDK4/6 inhibitors have been most effective in the context of functional RB1 and low expression or deletion of p16 in other tumor types, these data suggest such agents may merit evaluation in HPV-negative SCCHN, specifically in cases associated with high p^T356RB1.

Oral cavity and oropharyngeal squamous cell carcinoma--an update

Oral cavity squamous cell carcinoma (OC-SCC) is the most common malignancy of the head and neck (excluding nonmelanoma skin cancer). Recent trends have shown a dramatic rise in the incidence of oropharyngeal squamous cell carcinoma (OP-SCC), with a marked increase in lesions related to human papillomavirus infection. This update presents the latest evidence regarding OC-SCC and OP-SCC. In particular, the authors compare and contrast tumors at these two sites with respect to epidemiology, etiopathogenesis, clinicopathologic presentation, clinical assessment, imaging, management, and prognosis. It is important for clinicians to be aware of differences between OC-SCC and OP-SCC so that appropriate patient education and multidisciplinary care can be provided to optimize outcomes.

The protective effect of p16(INK4a) in oral cavity carcinomas: p16(Ink4A) dampens tumor invasion-integrated analysis of expression and kinomics pathways

A large body of evidence shows that p16(INK4a) overexpression predicts improved survival and increased radiosensitivity in HPV-mediated oropharyngeal squamous cell carcinomas.(OPSCC). Here we demonstrate that the presence of transcriptionally active HPV16 in oral cavity squamous cell carcinomas does not correlate with p16(INK4a) overexpression, enhanced local tumor immunity, or improved outcome. It is interesting that HPV-mediated oropharyngeal squamous cell carcinomas can be categorized as having a 'nonaggressive' invasion phenotype, whereas aggressive invasion phenotypes are more common in HPV-negative squamous cell carcinomas. We have developed primary cancer cell lines from resections with known pattern of invasion as determined by our validated risk model. Given that cell lines derived from HPV-mediated oropharyngeal squamous cell carcinomas are less invasive than their HPV-negative counterparts, we tested the hypothesis that viral oncoproteins E6, E7, and p16(INK4a) can affect tumor invasion. Here we demonstrate that p16(INK4a) overexpression in two cancer cell lines (UAB-3 and UAB-4), derived from oral cavity squamous cell carcinomas with the most aggressive invasive phenotype (worst pattern of invasion type 5 (WPOI-5)), dramatically decreases tumor invasiveness by altering expression of extracellular matrix remodeling genes. Pathway analysis integrating changes in RNA expression and kinase activities reveals different potential p16(INK4a)-sensitive pathways. Overexpressing p16(INK4a) in UAB-3 increases EGFR activity and increases MMP1 and MMP3 expression, possibly through STAT3 activation. Overexpressing p16(INK4a) in UAB-4 decreases PDGFR gene expression and reduces MMP1 and MMP3, possibly through STAT3 inactivation. Alternatively, ZAP70/Syk might increase MUC1 phosphorylation, leading to the observed decreased MMP1 expression.

Association between P16INK4a promoter methylation and HNSCC: a meta-analysis of 21 published studies

Background

The p16^INK4a is an important tumor suppressor gene (TSG) and aberrant methylation of promoter is known to be a major inactivation mechanism of the tumor suppressor and tumor-related genes. Aberrant TSG methylation was considered an important epigenetic silencing mechanism in the progression of head and neck squamous cell carcinoma (HNSCC). However, some studies have reported differences in the methylation frequencies of P^16INK4a promoter between cancer and the corresponding control group. Therefore, we conducted a meta-analysis to better identify the association.

Methods

PubMed, Ovid, ISI Web of Science, and EMBASE were searched to identify eligible studies to evaluate the association of p16^INK4a promoter methylation and HNSCC. Odds ratio (ORs) and 95% confidence intervals (95%CI) were calculated to evaluate the strength of association between p16^INK4a promoter methylation and HNSCC.

Results

A total of twenty-one studies with 1155 cases and 1017 controls were included in the meta-analysis. The frequencies of p16^INK4a promoter methylation in the cancer group were significantly higher than those in the control group (cancer group: median: 46.67%, range = 7.84%-95.12%; control group: median: 18.37%, range = 0–83.33%; respectively). The pooled odds ratio was 3.37 (95%CI = 2.32–4.90) in the cancer group versus the corresponding control group under the random-effects model.

Conclusion

This meta-analysis of 21 published studies identified that aberrant methylation of p16^INK4a promoter was found to be significantly associated with HNSCC.

Detection of HPV-associated oropharyngeal tumours in a 16-year cohort: more than meets the eye

BACKGROUND

Accurate assessment of the prevalence of the human papilloma virus (HPV) in oropharyngeal tumours (OpSCC) is important because HPV-positive OpSCC are consistently associated with an improved overall survival. Recently, an algorithm has become available that reliably detects clinically relevant HPV in tumour tissue, however, no complete cohorts have been tested. The aim was to determine the prevalence of active high-risk HPV infection in a complete cohort of OpSCC collected over a 16-year period.

METHODS

Using a triple algorithm of p16 immunohistochemistry, HPV-BRISH and HPV-PCR, we assessed the prevalence of active HPV infection in all OpSCC diagnosed in our hospital from 1997 to 2012 (n=193) and a random selection of 200 oral tumours (OSCC).

RESULTS

Forty-seven OpSCC (24%) were HPVGP PCR-positive; 42 cases were HPV16+, 1 HPV18+, 3 HPV33+ and 1 HPV35+. Brightfield in situ hybridisation did not identify additional HPV-positive cases. Human papilloma virus-associated tumour proportion increased from 13% (1997-2004) to 30% (2005-2012). Human papilloma virus-positivity was an independent predictor for longer disease-specific survival (HR=0.22; 95%CI:0.10-0.47). Only one OSCC was HPV+.

CONCLUSIONS

In our cohort, the incidence of HPV-associated OpSCC is low but increasing rapidly. The strict detection algorithm, analysis of disease-specific survival and the complete cohort, including palliatively treated patients, may influence the reported prevalence and prognostic value of HPV in OpSCC.

Epigenetic changes in the CDKN2A locus are associated with differential expression of P16INK4A and P14ARF in HPV-positive oropharyngeal squamous cell carcinoma

Human papillomavirus (HPV)-positive oropharyngeal squamous cell carcinoma (OPSCC) is recognized as a distinct disease entity associated with improved survival. DNA hypermethylation profiles differ significantly by HPV status suggesting that a specific subset of methylated CpG loci could give mechanistic insight into HPV-driven OPSCC. We analyzed genome-wide DNA methylation of primary tumor samples and adjacent normal mucosa from 46 OPSCC patients undergoing treatment at Montefiore Medical Center, Bronx, NY using the Illumina HumanMethylation27 beadchip. For each matched tissue set, we measured differentially methylated CpG loci using a change in methylation level (M value). From these analyses, we identified a 22 CpG loci panel for HPV+ OPSCC that included four CDKN2A loci downstream of the p16(INK4A) and p14(ARF) transcription start sites. This panel was significantly associated with overall HPV detection (P < 0.05; ROC area under the curve = 0.96, 95% CI: 0.91-1.0) similar to the subset of four CDKN2A-specific CpG loci (0.90, 95% CI: 0.82-0.99) with equivalence to the full 22 CpG panel. DNA hypermethylation correlated with a significant increase in alternative open reading frame (ARF) expression in HPV+ OPSCC primary tumors, but not to the other transcript variant encoded by the CDKN2A locus. Overall, this study provides evidence of epigenetic changes to the downstream region of the CDKN2A locus in HPV+ oropharyngeal cancer that are associated with changes in expression of the coded protein products.

Association of immunoexpression of the galectins-3 and -7 with histopathological and clinical parameters in oral squamous cell carcinoma in young patients

An increasing incidence of oral squamous cell carcinoma (OSCC) in individuals younger than 45 years has been observed in recent years. OSCC in younger patients differs in terms of biological behavior and prognosis with the disease being more aggressive than in older patients. The aim of this study was to analyze the immunohistochemical expression of galectins-3 and -7 in 32 cases of OSCC in young patients and to correlate this expression with clinical and morphological parameters. All cases of OSCC of the sample were diagnosed at oncology referral hospitals in Paraíba, Brazil, between 2002 and 2012. Clinical data were obtained from the patient records. Histological malignancy grading systems proposed by Bryne et al. (J Pathol 166:375-381, 1992) and the World Health Organization (In: Pathology and genetics of head and neck tumours: Word Health Organization classification of tumours, 2005) were used for morphological analysis. Immunohistochemistry was performed by the streptavidin-biotin technique using anti-galectin-3 and -7 antibodies. The results were analyzed statistically by the Chi-squared and Fisher exact tests (p < 0.05). Immunoexpression of galectin-3 was observed in 65.6 % of the cases analyzed, but showed no significant association with any of the variables studied (clinical staging; histological malignancy grading systems). Immunoexpression of galectin-7 was observed in 96.9 % of cases and was significantly associated with histological malignancy grading systems (p < 0.05). In conclusion, the results suggest the use of galectin-7 as marker of biological behavior and tumor progression in OSCC in young patients.

Quantitative methodology is critical for assessing DNA methylation and impacts on correlation with patient outcome

BACKGROUND

DNA hypermethylation is reported as a frequent event and prognostic marker in head and neck squamous cell carcinomas (HNSCC). Methylation has been commonly assessed with non-quantitative methodologies, such as methylation-specific PCR (MSP). We investigated previously reported hypermethylated genes with quantitative methodology in oral tongue squamous cell carcinomas (OTSCC).

RESULTS

The methylation status of 12 genes in 115 OTSCC samples was assessed by one or more of three quantitative analyses: methylation sensitive high resolution melting (MS-HRM), sensitive-melting analysis after real time-methylation specific PCR (SMART-MSP), and bisulfite pyrosequencing. In contrast to much of the literature, either no or infrequent locus-specific methylation was identified by MS-HRM for DAPK1, RASSF1A, MGMT, MLH1, APC, CDH1, CDH13, BRCA1, ERCC1, and ATM. The most frequently methylated loci were RUNX3 (18/108 methylated) and ABO (22/107 methylated). Interrogation of the Cancer Genome Atlas (TCGA) HNSCC cohort confirmed the frequency of significant methylation for the loci investigated. Heterogeneous methylation of RUNX3 (18/108) and ABO (22/107) detected by MS-HRM, conferred significantly worse survival (P = 0.01, and P = 0.03). However, following quantification of methylation levels using pyrosequencing, only four tumors had significant quantities (>15%) of RUNX3 methylation which correlated with a worse patient outcome (P <0.001), while the prognostic significance of ABO hypermethylation was lost. RUNX3 methylation was not prognostic for the TCGA cohort (P = 0.76).

CONCLUSIONS

We demonstrated the critical need for quantification of methylation levels and its impact on correlative analyses. In OTSCC, we found little evidence of significant or frequent hypermethylation of many loci reported to be commonly methylated. It is likely that previous reports have overestimated the frequency of significant methylation events as a consequence of the use of non-quantitative methodology.

Squamous Cell Carcinoma - Similarities and Differences among Anatomical Sites

Squamous cell carcinoma (SCC) is an epithelial malignancy involving many anatomical sites and is the most common cancer capable of metastatic spread. Development of early diagnosis methods and novel therapeutics are important for prevention and mortality reduction. In this effort, numerous molecular alterations have been described in SCCs. SCCs share many phenotypic and molecular characteristics, but they have not been extensively compared. This article reviews SCC as a disease, including: epidemiology, pathology, risk factors, molecular characteristics, prognostic markers, targeted therapy, and a new approach to studying SCCs. Through this comparison, several themes are apparent. For example, HPV infection is a common risk factor among the four major SCCs (NMSC, HNSC, ESCC, and NSCLC) and molecular abnormalities in cell-cycle regulation and signal transduction predominate. These data reveal that the molecular insights, new markers, and drug targets discovered in individual SCCs may shed light on this type of cancer as a whole.

Role of human papillomavirus in oropharyngeal squamous cell carcinoma: A review

Human papillomavirus (HPV) has been implicated in the pathogenesis of a subset of oropharyngeal squamous cell carcinoma. As a result, traditional paradigms in relation to the management of head and neck squamous cell carcinoma have been changing. Research into HPV-related oropharyngeal squamous cell carcinoma is rapidly expanding, however many molecular pathological and clinical aspects of the role of HPV remain uncertain and are the subject of ongoing investigation. A detailed search of the literature pertaining to HPV-related oropharyngeal squamous cell carcinoma was performed and information on the topic was gathered. In this article, we present an extensive review of the current literature on the role of HPV in oropharyngeal squamous cell carcinoma, particularly in relation to epidemiology, risk factors, carcinogenesis, biomarkers and clinical implications. HPV has been established as a causative agent in oropharyngeal squamous cell carcinoma and biologically active HPV can act as a prognosticator with better overall survival than HPV-negative tumours. A distinct group of younger patients with limited tobacco and alcohol exposure have emerged as characteristic of this HPV-related subset of squamous cell carcinoma of the head and neck. However, the exact molecular mechanisms of carcinogenesis are not completely understood and further studies are needed to assist development of optimal prevention and treatment modalities.

miR-639 promotes the proliferation and invasion of breast cancer cell in vitro

Breast cancer is characterised by an elevated capacity for tumour invasion and lymph node metastasis, but the cause remains to be determined. Recent studies suggest that microRNAs can regulate the evolution of malignant behaviours by regulating multiple target genes. In this study, we have first confirmed that miR-639 is up-regulated in metastatic breast cancer tissues and cell line with highly invasive capacity. Furthermore, we provided evidence to demonstrate that up-regulation of miR-639 contributes breast cancer invasion and metastasis. These data reveal a key role of miR-639 in breast cancer metastasis and support biological and clinical links between miR-639 and breast cancer.

p16INK4A and p14ARF gene promoter hypermethylation as prognostic biomarker in oral and oropharyngeal squamous cell carcinoma: a review

Head and neck squamous cell carcinoma is a heterogeneous group of tumors with each subtype having a distinct histopathological and molecular profile. Most tumors share, to some extent, the same multistep carcinogenic pathways, which include a wide variety of genetic and epigenetic changes. Epigenetic alterations represent all changes in gene expression patterns that do not alter the actual DNA sequence. Recently, it has become clear that silencing of cancer related genes is not exclusively a result of genetic changes such as mutations or deletions, but it can also be regulated on epigenetic level, mostly by means of gene promoter hypermethylation. Results from recent studies have demonstrated that DNA methylation patterns contain tumor-type-specific signatures, which could serve as biomarkers for clinical outcome in the near future. The topic of this review discusses gene promoter hypermethylation in oral and oropharyngeal squamous cell carcinoma (OSCC). The main objective is to analyse the available data on gene promoter hypermethylation of the cell cycle regulatory proteins p16^INK4A and p14^ARF and to investigate their clinical significance as novel biomarkers in OSCC. Hypermethylation of both genes seems to possess predictive properties for several clinicopathological outcomes. We conclude that the methylation status of p16^INK4A is definitely a promising candidate biomarker for predicting clinical outcome of OSCC, especially for recurrence-free survival.

Tongue squamous cell carcinoma in young nonsmoking and nondrinking patients: 3 clinical cases of orthodontic interest

Oral squamous cell carcinoma traditionally affects older men who smoke and drink. A change in this profile has been reported because of an increased incidence in young nonsmoking and nondrinking patients. The purpose of this article was to describe a series of young nonsmoking and nondrinking patients diagnosed with tongue squamous cell carcinoma who had recently received orthodontic treatment or evaluation. Details regarding diagnosis, treatment, follow-up, and disease evolution are presented, with a review of the pertinent literature. Orthodontists often treat young adults, who have frequent dental appointments and long-term follow-ups. Thus, practitioners should pay special attention to young patients during dental consultations, since the incidence of malignant oral lesions in this segment of the population seems to be increasing.

Differences in methylation profiles between HPV-positive and HPV-negative oropharynx squamous cell carcinoma: a systematic review

Oropharyngeal squamous cell carcinoma (OPSCC) is associated with human papillomavirus (HPV). HPV-positive OPSCC is considered a distinct molecular entity with a better prognosis than HPV-negative cases of OPSCC. However, the exact pathogenic mechanisms underlying the differences in clinical and molecular behavior between HPV-positive and HPV-negative OPSCC remain poorly understood. Epigenetic events play an important role in the development of cancer. Hypermethylation of DNA in promoter regions and global hypomethylation are 2 epigenetic changes that have been frequently observed in human cancers. It is suggested that heterogeneous epigenetic changes play a role in the clinical and biological differences between HPV-positive and HPV-negative tumors. Unraveling the differences in methylation profiles of HPV-associated OPSCC may provide for promising clinical applications and may pave the road for personalized cancer treatment. This systematic review aims to assess the current state of knowledge regarding differences in promoter hypermethylation and global methylation between HPV-positive and HPV-negative OPSCC.

An analysis of the epidemiological and etiological factors of oral tumors of young adults in a Central-Eastern European population

The etiology of tumors in young age is not precisely known yet, but studies on the topic generally agree that in this group of patients the traditionally known behavioural risk factors (tobacco and alcohol abuse) play no or a significantly less important role. Oral squamous cell carcinoma occurring at a young age is a topic of utmost importance that is extensively and intensively researched as, while the overall incidence of oral cancer is decreasing worldwide, that of squamous cell carcinoma diagnosed in young adults is steadily increasing. The present article aims at presenting the main questions and characteristics of tumors in young adults in Central-Eastern Europe and in developed West European countries as contrasted to tumors found in middle aged and elderly patients. Factors influencing the development of oral cancer include regulatory factors of the cell cycle, the inherited vulnerability of the genetic code of certain proteins and the presence of HPV infection with an oncogenic genotype. The connections of HPV infection and genetic damages are studied intensively. It is known that the prevalence of oral HPV infections is growing with a background of potentially changing sexual habits. It is debated, however, whether smoking and alcohol consumption could have a connection to HPV associated oral cancer and whether the spread of HPV in itself could be an explanation for the growing occurrence of young-age tumors. There is no consensus in the literature as to the prognostic significance of age. Some research groups have found a better life expectancy for young patients, while other authors found a worse prognosis for these patients. It is known that the prognosis of head and neck tumors, the prevalence of HPV infections as well as genetic mutations show regional and ethnic variations. This might be explained by differences in the degree of development of a preventive system, in the quality of care and in the attitudes of young patients towards visiting a doctor. The study is made difficult by incomparable patient selection criteria as well as by the question of the intraoral localisation of tumors as an independent risk factor.

Cyclin D1 overexpression is associated with poor prognosis in oropharyngeal cancer

OBJECTIVES

To determine the biological characteristics of oropharyngeal squamous cell carcinoma (OpSCC) and related outcome.

DESIGN

Retrospective study.

METHODS

Patients (N=60) with primary OpSCC from 2000 to 2005 were retrospectively identified from Pathology database and the outcome was confirmed through chart review. Among these, 41 biopsy samples with enough tissues were retrieved to construct a tissue microarray for detection of the presence of high-risk human papillomavirus (HPV) using Chromogenic in situ hybridization (CISH) as well as the expression of p16 and cyclin D1 using immunohistochemistry.

MAIN OUTCOME MEASURES

Disease-free survival.

RESULTS

Among 60 patients, 39 (65%) patients had no recurrence or died without disease at the last follow-up (disease-free survival or Group 1), and 21 (35%) patients had persistent disease or died of disease (progression-free survival or Group 2). Although follow-up time was twice as long in group 1 (4.7 ± 2.2 vs. 2.0 ± 1.6 years; P < 0.0001), there was no difference between the 2 groups in age, gender, smoking/alcohol habits, TNM staging and treatment modalities. Among those 41 cases with available tumour tissues, there was no difference in HPV status and p16 expression between the 2 groups but a significant difference in cyclin D1 expression (P = 0.05). Using Kaplan-Meir survival analysis and log-rank test, cyclin D1 overexpression was highly associated with a poor prognosis when comparing time to outcome (P < 0.0001).

CONCLUSION

Cyclin D1 overexpression is a potential prognostic marker of OpSCC.

Dysregulated miR-363 affects head and neck cancer invasion and metastasis by targeting podoplanin

Head and neck squamous cell carcinoma (HNSCC) is characterised by an elevated capacity for tumour invasion and lymph node metastasis and the cause remains to be determined. Recent studies suggest that microRNAs can regulate the evolution of malignant behaviours by regulating multiple target genes. In this study, we have first confirmed that miR-363 is down-regulated in HNSCC tissues with lymph node metastasis and cell lines with highly invasive capacity. We used bioinformatics, cellular and molecular methods to predict and prove that miR-363 directly targeted to podoplanin (PDPN) and caused up-regulation of PDPN in HNSCC. MSP assay showed that DNA promoter methylation was involved in silencing the miR-363 in HNSCC. Furthermore, we provided evidence to demonstrate that PDPN dysregulation caused by down-regulation of miR-363 contributes to HNSCC invasion and metastasis. These data reveal a key role of miR-363-PDPN in HNSCC metastasis and support biological and clinical links between miR-363-PDPN and HNSCC.

Human papillomavirus infection and papillary squamous cell carcinoma in the head and neck region

Papillary squamous cell carcinoma (PSCC) is a rare variant of SCC in the head and neck region. The role of human papillomavirus (HPV) infection in PSCC is still unclear. We retrospectively reviewed 11 PSCCs in our institute over a 21-year period and compared the HPV status of PSCCs with 26 squamous cell papillomas (SCPs). Polymerase chain reaction (PCR) amplification to detect HPV DNA and in situ hybridization (ISH) were performed to analyze the relationship between the papillary lesions and HPV infection. Immunohistochemical (IHC) staining for p16 protein expression was used to analyze the PSCC specimens. Nine of 11 (82 %), eight of 11 (73 %), and eight of 11 (73 %) PSCC samples were found to be HPV positive by PCR, ISH, and IHC staining for p16 protein expression, respectively. PSCC had a significantly higher rate of HPV infection than SCP by PCR (p = 0.002) and ISH (p = 0.001) analysis. This study presents different HPV status in two papillary neoplasms and may help to clarify the unique morphological and biological characteristics of head and neck PSCC.

Evaluation of ProExC as a prognostic marker in oropharyngeal squamous cell carcinomas

ProExC expression has been shown to perform similarly to p16 as an aid in the diagnosis of cervical dysplasia but has not been well characterized in head and neck squamous cell carcinomas (SCC). The purpose of this study is to determine whether ProExC performs similarly to p16 as a prognostic marker in oropharyngeal SCC and to evaluate the threshold of ProExC and p16 staining that correlates with survival. ProExC, p16, and human papillomavirus DNA in situ hybridization were performed on tissue microarray (TMA) cores and whole sections from 62 patients with oropharyngeal SCC. Sensitivity and specificity for high-risk HPV and correlation with overall survival (OS), cancer-specific survival (CSS), and time to distant metastasis (TDM) were calculated for ProExC and p16 at different thresholds. ProExC did not prove to be a robust marker. It showed strong correlation with OS at a 66% threshold on TMA cores, but correlation with OS was lost on whole sections. It also exhibited low sensitivity (53.7%) on TMA cores and low specificity on whole sections (65%). ProExC at a 33% threshold exhibited unacceptably low specificity and did not correlate with OS, CSS, or TDM. Sensitivity and specificity of p16 varied predictably with threshold: higher sensitivity and lower specificity with lower thresholds and vice versa for higher thresholds. p16 at a 50% threshold offers a balance between sensitivity and specificity, and correlates with OS, CSS, and TDM on whole sections; correlation with TDM is lost on TMA cores. These findings indicate that ProExC does not perform well enough to be used as a prognostic marker in oropharyngeal SCC. p16 should be used and scored as positive when at least half the tumor is strongly stained.

HPV DNA, E6*I-mRNA expression and p16INK4A immunohistochemistry in head and neck cancer - how valid is p16INK4A as surrogate marker?

It has been proposed that p16(INK4A) qualifies as a surrogate marker for viral oncogene activity in head and neck cancer (HNSCC). By analyzing 78 HNSCC we sought to validate the accuracy of p16(INK4A) as a reliable marker of active HPV infections in HNSCC. To this end we determined HPV DNA (HPVD) and E6*I mRNA (HPVR) expression status and correlated these results with p16(INK4A) staining. In tonsillar SCC 12/20 were HPVD+ and 12/12 of these showed active HPV infections whereas in non-tonsillar SCC 10/58 were HPVD+ and 5/10 showed active HPV infections. Thus, we prove about 8% of non-tonsillar SCC to be also correlated with HPV-associated carcinogenesis. Strikingly, 3/14 (21.4%) of tonsillar and non-tonsillar HPVD+/HPVR+ cases did not show p16(INK4A) overexpression and these cases would have been missed when applying initial p16(INK4A) staining only. However, in 13 cases negative for HPV, DNA p16(INK4A) was overexpressed. In conclusion, our data confirm tonsillar SCC to be predominantly but not only associated with active HPV infections. Furthermore, our data show that p16(INK4A) overexpression is not evident in a subgroup of HNSCC with active HPV infection. Definitive HPV data should therefore be utilized in diagnostics and treatment modalities of HPV positive and HPV negative HNSCC patients, resulting in a paradigm shift regarding these obviously different tumor entities.

Loss of protein expression and recurrent DNA hypermethylation of the GNG7 gene in squamous cell carcinoma of the head and neck

Although down-regulation of GNG7 in cancer was reported before, its role in carcinogenesis is poorly understood. It belongs to a family of large G-proteins that may be involved in cell-contact-induced growth arrest and function in tumor suppression. In the present study, we stained immunohistochemically 188 tumors derived from larynx or floor of the mouth for GNG7 protein and confronted it with clinicopathologic data. Moreover, we performed bisulfite pyrosequencing to analyze GNG7 promoter methylation. We identified recurrent loss of GNG7 protein expression in 68/188 (36%) cases and promoter hypermethylation in (42/98; 43%) primary tumors, predominantly in young patients (p < 0.001). Loss of GNG7 expression correlated with hypermethylation of GNG7 promoter region (p < 0.001). Moreover, loss of GNG7 protein expression correlated with tumor size (p = 0.012) and lack of cervical metastasis (p = 0.02) whereas sustained expression correlated with keratinization (p = 0.008). Taken together, loss of GNG7 protein expression is a frequent event in head and neck cancer. Moreover, our data suggest that hypermethylation of the promoter region of GNG7 is probably the mechanism of the observed inactivation.

Benefit of chemotherapy as part of treatment for HPV DNA-positive but p16-negative squamous cell carcinoma of the oropharynx

Background:

To determine (a) the cause of an improvement in survival from oropharyngeal squamous cell carcinoma (OSCC) in South East Scotland and (b) whether this improvement was human papillomavirus (HPV) and p16 subtype-dependent.

Methods:

Clinicopathological characteristics and outcome data for patients referred with OSCC from 1999 to 2001 (Cohort-1) and 2003 to 2005 (Cohort-2) were obtained. Molecular HPV detection and immunohistochemistry for p16 were performed from paraffin blocks.

Results:

Cohort-1 and Cohort-2 contained 118 and 136 patients, respectively. Kaplan–Meier analysis revealed significantly improved survival in Cohort-2 (P<0.0001). Sub-classification according to HPV and p16 status revealed no improvement in survival in Class-I (HPV−ve/p16−ve; 47 patients) or Class-III (HPV+ve/p16+ve; 77 patients). However in Class-II (HPV+ve/p16−ve; 56 patients) an increase in 5-year cause-specific survival from 36% in Cohort-1 to 73% in Cohort-2 was detected (P=0.0001).

Proportional hazards analysis of 217 patients treated radically demonstrated that significant variables were p16 (P<0.0001), N stage (P=0.0006) and cohort (P=0.0024). Removing cohort from the variables offered to the model showed that, whereas p16 (P<0.0001) and N stage (P=0.0016) remain significant, chemotherapy (P=0.0163) and T stage (P=0.0139) are now significant. This suggests that much of the cohort effect is due to the higher use of chemotherapy in the second cohort.

Conclusion:

These data suggest that HPV+ve/p16−ve patients constitute a separate subclass of OSCC who may particularly benefit from chemotherapy. They imply that p16 status cannot be considered a surrogate for HPV status, and those trials to de-escalate treatment in HPV+ve OSCC should take p16 status into account.

Increasing Incidence of Oral Tongue Squamous Cell Carcinoma in Young White Women, Age 18 to 44 Years

Purpose

To evaluate the incidence of oral cavity squamous cell carcinoma (OCSCC) and oral tongue squamous cell carcinoma (OTSCC) in young white women, age 18 to 44 years.

Patients and Methods

We analyzed incidence and survival data from the Surveillance, Epidemiology and End Results (SEER) Program of the National Cancer Institute from 1975 to 2007 for OCSCC and OTSCC. Three cohorts were examined: all ages, age 18 to 44 years (ie, “young”), and age > 44 years. Individuals were stratified by sex and/or race. Percentage change (PC) and annual percentage change (APC) were calculated. Joinpoint regression analyses were performed to examine trend differences.

Results

Overall, incidence of OCSCC was decreasing for all ages. However, incidence was increasing for young white women (PC, 34.8; APC, 2.2; P < .05). Incidence of OTSCC was decreasing for all ages except in the age 18 to 44 years group (PC, 28.8; APC, 1.8; P < .05). Young white individuals had increasing incidence trends of OTSCC (white women: PC, 111.3; APC, 4; P < .05; young white men: PC, 43.7; APC, 1.6; P < .05). The APC of OTSCC was significantly greater in young white women compared with that in young white men (P = .007). Furthermore, incidence of SCC in all other subsites of the oral cavity was decreasing. Nonwhites had a decreasing incidence of OCSCC and OTSCC. Cause-specific survival was similar among whites age 18 to 44 and individuals older than age 44 years.

Conclusion

OTSCC is increasing among young white individuals age 18 to 44 years, particularly among white women. Young white women may be a new, emerging head and neck cancer patient population.

Epigenetic silencing of MAL, a putative tumor suppressor gene, can contribute to human epithelium cell carcinoma

BACKGROUND

To identify new and useful candidate biomarkers in head and neck squamous cell carcinoma (HNSCC), we performed a genome-wide survey and found that Myelin and lymphocyte-associated protein (MAL) was a gene that was markedly down-regulated in HNSCC. Hence, we investigated the mechanism of MAL silencing and the effects of MAL on the proliferation, invasion, and apoptotic potential in HNSCC.

RESULTS

MAL was significantly down-regulated in 91.7% of HNSCC specimens at the mRNA level as compared with adjacent normal tissues (P = 0.0004). Moreover, the relative transcript levels of the MAL gene were remarkably decreased by five-fold in nine HNSCC cell lines as compared with normal head and neck epithelium cells. MAL gene expression was restored in 44%, 67%, and 89% in HNSCC cell lines treated with TSA, 5-Aza-dC, and TSA plus 5-Aza-dC, respectively. Furthermore, bisulfate-treated DNA sequencing demonstrated that the two CpG islands (that is, M1 and M2) located in MAL promoter region were completely methylated in the HNSCC cell lines (CpG methylated ratio was more than 90%), and only one CpG island (that is, M1) was partially methylated in HNSCC tissues (CpG methylated ratio between 20% and 90%). A significant reduction in cell proliferation and a change in the cell cycle profile were also observed in MAL transfectants. Matrigel assay demonstrated that the invasiveness of HNSCC cells significantly decreased. A significant increase in the population of apoptotic cells was observed in MAL transfected cells. The exogenous expression of the MAL gene suppressed malignant phenotypes, while the cell death induced by MAL gene transfer was a result of apoptosis as demonstrated by the induction of cleavage of the poly (that is, ADP-ribose) polymerase. Additionally, tumor growth was suppressed in cells expressing MAL as compared with cells not expressing MAL.

CONCLUSION

Our data suggest that the epigenetic inactivation of MAL, as a candidate tumor suppressor gene, can contribute to human epithelial cell carcinoma and may be served as a biomarker in HNSCC.

Promoter hypermethylation in Indian primary oral squamous cell carcinoma

We evaluated promoter hypermethylation of a panel of tumor suppressor genes as a means to detect epigenetic alterations in oral squamous cell carcinomas (OSCC) of Indian-origin and compare with North-American head and neck squamous cell carcinomas (HNSCC). Quantitative-methylation-specific PCR was used to investigate the promoter methylation status of DCC, EDNRB, p16(INK4a) and KIF1A in 92 OSCC, and compared to 48 paired normal tissues and 30 saliva and sera samples from healthy control subjects. Aberrant methylation of at-least one of these genes was detected in 74/92 (80.4%) OSCC; 72.8% at EDNRB, 71.7% at KIF1A, 47.8% at p16(INK4a) and 58.7% at DCC; and in 5 of 48 (10.4%) normal oral tissues. None of the saliva and sera samples from controls exhibited DNA methylation in these four target genes. Thirty-two of 72 node positive cases harbored p16(INK4a) and DCC hypermethylation (p = 0.005). Thus, promoter hypermethylation in genes analyzed herein is a common event in Indian OSCC and may represent promising markers for the molecular staging of OSCC patients. We found higher frequency of p16(INK4a) methylation (47.8%) in this Indian cohort in comparison with a North-American cohort (37.5%). In conclusion, aberrant methylation of EDNRB, KIF1A, DCC and p16(INK4a) genes is a common event in Indian OSCC, suggesting that epigenetic alterations of these genes warrant validation in larger studies for their potential use as biomarkers.

Schneiderian Papillomas and Carcinomas: A Retrospective Study with Special Reference to p53 and p16 tumor suppressor gene expression and association with HPV

Schneiderian papillomas are uncommon benign tumors of the sinonasal area. They are prone to local aggressiveness and recurrence, and some undergo malignant progression. We analyzed specimens obtainedfrom 67 Chinese patients who had presented to the ENT department of a regional hospital with biopsy-proven schneiderian papilloma. Seven of these patients had either synchronous or metachronous carcinoma, 1 of whom had pure carcinoma in situ. For each case, we documentedthe morphology, immunohistochemical expression of tumor suppressor genes p53 and p16, and any association with human papillomavirus (HPV) infection as detected by either polymerase chain reaction or in situ hybridization techniques. We found that severe dysplasia andp53positivity were strongly associated with malignantprogression. Association with HPV was demonstrated in 22 of the 67patients (33%); the association was strongest among patients with exophytic papillomas and carcinomas. The effect of HPV in papilloma oncogenesis probably begins duringthe early phase, while other factors are responsible for progression to carcinoma. We conclude thatp53-positive, dysplastic schneiderian papillomas warrant aggressive surgical treatment.

Human papillomavirus and oropharynx cancer: biology, detection and clinical implications

OBJECTIVES

To review evidence for the role of human papillomavirus (HPV) in the etiology of oropharyngeal cancers, methods of viral detection, and the resulting clinical implications.

STUDY DESIGN

Contemporary review.

METHODS

Published journal articles identified through PubMed and conference proceedings were reviewed.

RESULTS

HPV-associated squamous cell carcinomas represent a distinct disease entity from carcinogen-associated squamous cell carcinomas. HPV oncoproteins lead to mucosal cell transformation through well-defined mechanisms. Different methods of detecting HPV exist with variable levels of sensitivity and specificity for biologically active virus. Although virus is detected in a number of head and neck subsites, studies demonstrate improved outcomes in HPV-associated carcinoma of the oropharynx only. The cell cycle regulatory protein p16 is upregulated by biologically active HPV and serves as a biomarker of improved response to therapy.

CONCLUSIONS

HPV-associated squamous cell carcinoma of the oropharynx is a biologically distinct entity from carcinogen-associated carcinoma. Understanding the molecular mechanisms behind the improved outcomes in patients with HPV-associated oropharyngeal carcinoma may lead to novel therapeutics for patients with carcinogen-associated carcinomas.

Meta-analysis of the impact of human papillomavirus (HPV) on cancer risk and overall survival in head and neck squamous cell carcinomas (HNSCC)

BACKGROUND

HPV is important in a subset of HNSCC. Our meta-analysis determined the clinical characteristics of HPV-related HNSCC.

METHOD

Pubmed search terms "HPV" and "HNSCC" were used to identify 34 studies since 1980. We obtained pooled adjusted odds ratio (OR) or hazard ratio (HR) using random or fixed-effects model and compared OS depicted in forest plot.

RESULTS

A total of 5681 patients were included. The prevalence of HPV+ tumors was 22%, with 86.7% of HPV16+ genotype. The OR for HNSCC in HPV16+ patients was 4.44 (95% CI = 2.87-6.02). HPV status was associated with p16 expression (adj OR = 3.00; 0.90-9.70), and HPV+ tumors were less likely to harbor p53 mutations (adj OR = 0.21; 0.04-0.38). The HR for death in HPV+ patients was 0.42 (0.27-0.57). HPV+ HNSCC also had a better response to therapy.

CONCLUSION

HPV+ HNSCC are established as a separate biologic entity. Prospective trials are needed to establish the optimal therapy for HPV+ HNSCC.