Biological evidence that human papillomaviruses are etiologically involved in a subgroup of head and neck squamous cell carcinomas

Current Evidence of a Deintensification Strategy for Patients with HPV-Related Oropharyngeal Cancer

Simple Summary

Human papillomavirus (HPV)-related oropharyngeal cancer represents a distinct disease entity, showing favorable treatment responses and survival outcomes. While the deintensification of treatment for HPV-related oropharyngeal cancer is widely considered necessary, details concerning patient selection and optimal strategies are undetermined. The heterogeneity of study populations and interventions in trials complicate the ability of physicians to apply the results in daily practice. The evolving landscape also requires physicians to consistently update the results of these trials. This article reviews the most recent evidence on the deintensification of HPV-related oropharyngeal cancer. We aim to provide physicians with some guidance regarding management options and assist researchers in appropriately designing trials in the future.

Abstract

Human papillomavirus (HPV)-related oropharyngeal cancer differs from HPV-negative oropharyngeal cancer in terms of etiology, epidemiology, and prognosis. Younger and lower comorbidity patient demographics and favorable prognosis allow HPV-related oropharyngeal cancer patients to anticipate longer life expectancy. Reducing long-term toxicities has become an increasingly important issue. Treatment deintensification to reduce toxicities has been investigated in terms of many aspects, and the reduction of radiotherapy (RT) dose in definitive treatment, replacement of platinum-based chemotherapy with cetuximab, response-tailored dose prescription after induction chemotherapy, and reduction of adjuvant RT dose after transoral surgery have been evaluated. We performed a literature review of prospective trials of deintensification for HPV-related oropharyngeal cancer. In phase II trials, reduction of RT dose in definitive treatment showed comparable survival outcomes to historical results. Two phase III randomized trials reported inferior survival outcomes for cetuximab-based chemoradiation compared with cisplatin-based chemoradiation. In a randomized phase III trial investigating adjuvant RT, deintensified RT showed noninferior survival outcomes in patients without extranodal extension but worse survival in patients with extranodal extension. Optimal RT dosage and patient selection require confirmation in future studies. Although many phase II trials have reported promising outcomes, the results of phase III trials are needed to change the standard treatment. Since high-level evidence has not been established, current deintensification should only be performed as part of a clinical study with caution. Implementation in clinical practice should not be undertaken until evidence from phase III randomized trials is available.

Immunotherapy Approaches in HPV-Associated Head and Neck Cancer

Immunotherapy approaches for head and neck squamous cell carcinoma (HNSCC) are rapidly advancing. Human papillomavirus (HPV) has been identified as a causative agent in a subset of oropharyngeal cancers (OPC). HPV-positive OPC comprises a distinct clinical and pathologic disease entity and has a unique immunophenotype. Immunotherapy with anti-PD1 checkpoint inhibitors has exhibited improved outcomes for patients with advanced HNSCC, irrespective of HPV status. To date, the clinical management of HPV-positive HNSCC and HPV-negative HNSCC has been identical, despite differences in the tumor antigens, immune microenvironment, and immune signatures of these two biologically distinct tumor types. Numerous clinical trials are underway to further refine the application of immunotherapy and develop new immunotherapy approaches. The aim of this review is to highlight the developing role of immunotherapy in HPV-positive HNSCC along with the clinical evidence and preclinical scientific rationale behind emerging therapeutic approaches, with emphasis on promising HPV-specific immune activators that exploit the universal presence of foreign, non-self tumor antigens.

HPV Status as Prognostic Biomarker in Head and Neck Cancer-Which Method Fits the Best for Outcome Prediction?

The incidence of human papillomavirus (HPV)-related head and neck cancer (HNSCC) is rising globally, presenting challenges for optimized clinical management. To date, it remains unclear which biomarker best reflects HPV-driven carcinogenesis, a process that is associated with better therapeutic response and outcome compared to tobacco/alcohol-induced cancers. Six potential HPV surrogate biomarkers were analyzed using FFPE tissue samples from 153 HNSCC patients (n = 78 oropharyngeal cancer (OPSCC), n = 35 laryngeal cancer, n = 23 hypopharyngeal cancer, n = 17 oral cavity cancer): p16, CyclinD1, pRb, dual immunohistochemical staining of p16 and Ki67, HPV-DNA-PCR, and HPV-DNA-in situ hybridization (ISH). Biomarkers were analyzed for correlation with one another, tumor subsite, and patient survival. P16-IHC alone showed the best performance for discriminating between good (high expression) vs poor outcome (low expression; p = 0.0030) in OPSCC patients. Additionally, HPV-DNA-ISH (p = 0.0039), HPV-DNA-PCR (p = 0.0113), and p16-Ki67 dual stain (p = 0.0047) were significantly associated with prognosis in uni- and multivariable analysis for oropharyngeal cancer. In the non-OPSCC group, however, none of the aforementioned surrogate markers was prognostic. Taken together, P16-IHC as a single biomarker displays the best diagnostic accuracy for prognosis stratification in OPSCC patients with a direct detection of HPV-DNA by PCR or ISH as well as p16-Ki67 dual stain as potential alternatives.

Phytochemicals as Potential Chemopreventive and Chemotherapeutic Agents for Emerging Human Papillomavirus-Driven Head and Neck Cancer: Current Evidence and Future Prospects

Head and neck cancer (HNC) usually arises from squamous cells of the upper aerodigestive tract that line the mucosal surface in the head and neck region. In India, HNC is common in males, and it is the sixth most common cancer globally. Conventionally, HNC attributes to the use of alcohol or chewing tobacco. Over the past four decades, portions of human papillomavirus (HPV)-positive HNC are increasing at an alarming rate. Identification based on the etiological factors and molecular signatures demonstrates that these neoplastic lesions belong to a distinct category that differs in pathological characteristics and therapeutic response. Slow development in HNC therapeutics has resulted in a low 5-year survival rate in the last two decades. Interestingly, HPV-positive HNC has shown better outcomes following conservative treatments and immunotherapies. This raises demand to have a pre-therapy assessment of HPV status to decide the treatment strategy. Moreover, there is no HPV-specific treatment for HPV-positive HNC patients. Accumulating evidence suggests that phytochemicals are promising leads against HNC and show potential as adjuvants to chemoradiotherapy in HNC. However, only a few of these phytochemicals target HPV. The aim of the present article was to collate data on various leading phytochemicals that have shown promising results in the prevention and treatment of HNC in general and HPV-driven HNC. The review explores the possibility of using these leads against HPV-positive tumors as some of the signaling pathways are common. The review also addresses various challenges in the field that prevent their use in clinical settings.

Frequency and Localization of Second Primary Tumors in Patients with Oropharyngeal Carcinoma-The Influence of the Human Papilloma Virus

Simple Summary

Human papillomavirus (HPV) infection, smoking, and excessive alcohol consumption have been established as risk factors for the development of oropharyngeal squamous cell carcinoma (OPSCC). While the HPV epidemic has led to an increasing incidence of OPSCC, HPV-negative OPSCC cases associated with smoking and alcohol remain stable. As HPV-positive and -negative OPSCC present two distinct etiological, clinical, and prognostic entities, different treatment and follow-up strategies are being discussed. Still, specific surveillance strategies for HPV-positive OPSCC are lacking, as the risk of second primary tumors (SPT) in the era of HPV-associated OPSCC has not been comprehensively assessed. Our study investigated the frequency and localization of SPT of HPV-positive OPSCC, as well as their prognostic impact. We find that the SPT of HPV-positive OPSCC are less frequent than those of HPV-negative OPSCC, and they are also associated with higher survival rates. The localization of SPT of HPV-positive OPSCC did not differ from the localization of SPT of HPV-negative OPSCC.

Abstract

Purpose: To investigate the frequency, localization, and survival of second primary tumors (SPT) of oropharyngeal squamous cell carcinoma (OPSCC) depending on human papillomavirus (HPV) status. Methods: We performed a retrospective chart analysis of 107 OPSCC patients treated at the Zurich University Hospital from 2001 to 2010. Rate and localization of SPT after an index OPSCC were stratified according to smoking and HPV infection status. Results: In total, 57/91 (63%) included patients showed an HPV-associated OPSCC. Of these, 37/57 (64.9%) patients with an HPV-positive and 32/34 (94.1%) patients with an HPV-negative OPSCC were smokers. The median age at diagnosis of the SPT was 59.54 years (interquartile range 52.7–65.6). In addition, 8/57 (14%) HPV-positive and 13/34 (38.2%) HPV-negative patients developed SPT. The rate of SPT in patients with HPV-positive index tumors was significantly lower than in patients with HPV-negative OPSCC (p-value 0.01). Smokers showed significantly more SPT in the head and neck area than outside. The development of an SPT led to a significantly lower survival time in HPV-negative patients, while it did not significantly affect the survival time of HPV-positive patients. Conclusions: Patients with HPV-positive index tumors had a significantly lower risk of developing SPT than patients with HPV-negative tumors. If SPT developed, survival was significantly shorter in patients with HPV-negative tumors than with HPV-positive tumors.

Clinical variables and magnetic resonance imaging-based radiomics predict human papillomavirus status of oropharyngeal cancer

BACKGROUND

Human papillomavirus (HPV)-positive oropharyngeal squamous cell carcinoma (OPSCC) have better prognosis and treatment response compared to HPV-negative OPSCC. This study aims to noninvasively predict HPV status of OPSCC using clinical and/or radiological variables.

METHODS

Seventy-seven magnetic resonance radiomic features were extracted from T1-weighted postcontrast images of the primary tumor of 153 patients. Logistic regression models were created to predict HPV status, determined with immunohistochemistry, based on clinical variables, radiomic features, and its combination. Model performance was evaluated using area under the curve (AUC).

RESULTS

Model performance showed AUCs of 0.794, 0.764, and 0.871 for the clinical, radiomic, and combined models, respectively. Smoking, higher T-classification (T3 and T4), larger, less round, and heterogeneous tumors were associated with HPV-negative tumors.

CONCLUSION

Models based on clinical variables and/or radiomic tumor features can predict HPV status in OPSCC patients with good performance and can be considered when HPV testing is not available.

Timing, number, and type of sexual partners associated with risk of oropharyngeal cancer

BACKGROUND

Case-control studies from the early 2000s demonstrated that human papillomavirus-related oropharyngeal cancer (HPV-OPC) is a distinct entity associated with number of oral sex partners. Using contemporary data, we investigated novel risk factors (sexual debut behaviors, exposure intensity, and relationship dynamics) and serological markers on odds of HPV-OPC.

METHODS

HPV-OPC patients and frequency-matched controls were enrolled in a multicenter study from 2013 to 2018. Participants completed a behavioral survey. Characteristics were compared using a chi-square test for categorical variables and a t test for continuous variables. Adjusted odds ratios (aOR) were calculated using logistic regression.

RESULTS

A total of 163 HPV-OPC patients and 345 controls were included. Lifetime number of oral sex partners was associated with significantly increased odds of HPV-OPC (>10 partners: odds ratio [OR], 4.3 [95% CI, 2.8-6.7]). After adjustment for number of oral sex partners and smoking, younger age at first oral sex (<18 vs >20 years: aOR, 1.8 [95% CI, 1.1-3.2]) and oral sex intensity (>5 sex-years: aOR, 2.8 [95% CI, 1.1-7.5]) remained associated with significantly increased odds of HPV-OPC. Type of sexual partner such as older partners when a case was younger (OR, 1.7 [95% CI, 1.1-2.6]) or having a partner who had extramarital sex (OR, 1.6 [95% CI, 1.1-2.4]) was associated with HPV-OPC. Seropositivity for antibodies to HPV16 E6 (OR, 286 [95% CI, 122-670]) and any HPV16 E protein (E1, E2, E6, E7; OR, 163 [95% CI, 70-378]) was associated with increased odds of HPV-OPC.

CONCLUSION

Number of oral sex partners remains a strong risk factor for HPV-OPC; however, timing and intensity of oral sex are novel independent risk factors. These behaviors suggest additional nuances of how and why some individuals develop HPV-OPC.

In situ hybridization for high risk HPV E6/E7 mRNA in oropharyngeal squamous cell carcinoma

OBJECTIVES

To report a single institution's experience using human papillomavirus (HPV) E6/E7 mRNA in-situ hybridization (mRNA ISH) for HPV detection in oropharyngeal squamous cell carcinoma (OPSCC). To review the literature on HPV detection methods.

STUDY DESIGN

Retrospective chart review, literature review.

SETTING

Tertiary care academic hospital.

SUBJECTS AND METHODS

We conducted a retrospective chart review of 122 OPSCC biopsy specimens. mRNA ISH was performed on formalin-fixed paraffin-embedded (FFPE) tissue with a pool of 18 high risk HPV probes using an automated stainer; p16 immunohistochemistry (IHC) was also performed. We conducted a literature review on HPV detection methods including p16 IHC, mRNA ISH, DNA ISH, and PCR.

RESULTS

In our cohort, mRNA ISH had a sensitivity and specificity of 100% and 100% with reference to p16 (100% concordance). 2-year OS was 87.5% vs. 94.5% for p16/HPV-negative vs. positive patients. 2-year DFS was 60.0% vs. 84.2%. On literature review, mRNA ISH demonstrated consistently high sensitivity and specificity ranging from 88-98% and 90-100% respectively. In comparison, the specificity of p16 was 85-95%.

CONCLUSIONS

Our report supports the use of mRNA ISH for HPV detection in OPSCC and validates its feasibility using automated tissue staining methods on FFPE tissue. Our findings and literature review support that mRNA ISH may have superior specificity and be easier to interpret than p16. Further study on the prognostic value and cost-effectiveness of mRNA ISH is warranted and may establish this HPV detection method as the "gold standard."

Human Papillomavirus Infection in Head and Neck Squamous Cell Carcinomas: Transcriptional Triggers and Changed Disease Patterns

Head and neck squamous cell carcinoma (HNSCC) is a heterogeneous group of cancers. Collectively, HNSCC ranks sixth in incidence rate worldwide. Apart from classical risk factors like tobacco and alcohol, infection of human papillomavirus (HPV) is emerging as a discrete risk factor for HNSCC. HPV-positive HNSCC represent a distinct group of diseases that differ in their clinical presentation. These lesions are well-differentiated, occur at an early age, and have better prognosis. Epidemiological studies have demonstrated a specific increase in the proportions of the HPV-positive HNSCC. HPV-positive and HPV-negative HNSCC lesions display different disease progression and clinical response. For tumorigenic-transformation, HPV essentially requires a permissive cellular environment and host cell factors for induction of viral transcription. As the spectrum of host factors is independent of HPV infection at the time of viral entry, presumably entry of HPV only selects host cells that are permissive to establishment of HPV infection. Growing evidence suggest that HPV plays a more active role in a subset of HNSCC, where they are transcriptionally-active. A variety of factors provide a favorable environment for HPV to become transcriptionally-active. The most notable are the set of transcription factors that have direct binding sites on the viral genome. As HPV does not have its own transcription machinery, it is fully dependent on host transcription factors to complete the life cycle. Here, we review and evaluate the current evidence on level of a subset of host transcription factors that influence viral genome, directly or indirectly, in HNSCC. Since many of these transcription factors can independently promote carcinogenesis, the composition of HPV permissive transcription factors in a tumor can serve as a surrogate marker of a separate molecularly-distinct class of HNSCC lesions including those cases, where HPV could not get a chance to infect but may manifest better prognosis.

Risk factors for the development of high-grade dysplasia and carcinoma in patients with laryngeal squamous cell papillomas: Large retrospective cohort study

BACKGROUND

The incidence and risk factors for the development of high-grade dysplasia (HG-D) and laryngeal squamous cell carcinoma (LSCC) were assessed in patients with laryngeal squamous cell papillomas (LSP).

METHODS

Clinical data, human papillomaviruses (HPV) typing, HPV E6/E7 mRNA in situ hybridization, and sequencing of host genes in LSP biopsies of 163 patients were analyzed.

RESULTS

Progression to HG-D and LSCC was identified in 21.5% and 4.3% of LSP patients, respectively. A more advanced age at LSP onset and lack of HPV infection were detected as risk factors for the development of HG-D and LSCC (P < .05). The identification of HG-D was associated with its progression to LSCC (P < .05). Host gene mutations were identified in 3 of 7 patients with LSCC.

CONCLUSIONS

The histological monitoring of LSP and HPV typing are necessary for early detection of epithelial changes. Further research is needed to elucidate the role of host gene mutations in LSCC transformation.

Comparison of Survival Estimates Following Recurrence, Persistence, or Second Primary Malignancy in Oropharyngeal Squamous Cell Carcinoma

OBJECTIVE

This study investigated survival among patients with oropharyngeal squamous cell carcinoma (OPSCC) after recurrence, persistence, and second primary malignancies (SPMs).

STUDY DESIGN

Retrospective cohort study.

SETTING

Patients were treated at a tertiary cancer center.

SUBJECTS AND METHODS

Patients with OPSCC who had completed treatment between 2001 and 2017 were included. Survival estimates of 4 groups of patients were calculated: (1) patients who were disease free after initial treatment, (2) patients who had persistent disease, (3) those with recurrent disease, and (4) patients with SPMs. Cox proportional hazard models and parametric survival analyses (using Weibull distributions) were used to obtain hazard ratios (HRs) and time ratios (TRs).

RESULTS

The cohort included 364 patients. The crude overall SPM prevalence was 8.2%. Mean overall survival (OS) time in years for patients who remained disease free after treatment was 4.02 years. Among patients who experienced recurrence, the recurrence-free survival (RFS) was 2.58 years while their mean (SD) OS was 3.67 (2.7) years. Participants who experienced persistence had a mean (SD) OS of 1.67 (1.68) years. Patients with observed SPMs had a mean (SD) OS of 6.39 (4.06) years since their primary cancer but shortened survivals of 1.75 (2.34) years since the secondary diagnosis. Differences were present even after accounting for human papillomavirus (HPV) and smoking status.

CONCLUSIONS

Our findings stress the importance of active surveillance as per current National Comprehensive Cancer Network guidelines, irrespective of the HPV status or smoking status. Prospective studies with a larger number of SPM cases and longer follow-up are needed to validate survival trends even beyond 5 years.

Automated RNA In Situ Hybridization for 18 High Risk Human Papilloma Viruses in Squamous Cell Carcinoma of the Head and Neck: Comparison With p16 Immunohistochemistry

Detection of human papilloma virus (HPV)-related head and neck squamous cell carcinoma (HNSCC) is important, as HPV-associated HNSCCs respond better to therapy. The RNAscope HPV-test is a novel RNA in situ hybridization (ISH) technique which strongly stains transcripts of E6 and E7 mRNA in formalin-fixed, paraffin-embedded tissue, with the potential to replace the indirect immunohistochemical (IHC) marker for p16 protein. A direct clinical comparison between p16 IHC and an automated RNA ISH using 18 probes has not been established. Samples from 27 formalin-fixed, paraffin-embedded HNSCC cases from the Emory University Hospital archives were stained using 18 individual RNA ISH probes for high-risk HPV (RNAscope 2.5 LS Probe ) on a Leica autostainer (Buffalo Grove, IL) and were compared with p16 IHC. Two pathologists reviewed and reached a consensus on all interpretations. The RNAscope technique was positive in 89% (24/27) and the p16 IHC was positive in 78% (21/27). The RNAscope was negative in 11.1% of samples (3/27) and the p16 IHC-negative in 22.2% (6/27). The RNA ISH detected 100% of the p16-positive IHC-stained slides and had a concordance of 88.9% (24/27). This easy to interpret automated staining method for 18 high-risk HPV genotypes is a feasible replacement for the indirect p16 IHC method.

Molecular Diagnostics in Human Papillomavirus-Related Head and Neck Squamous Cell Carcinoma

The incidence of human papillomavirus (HPV)-related head and neck squamous cell carcinoma continues to increase. Accurate diagnosis of the HPV status of a tumor is vital, as HPV+ versus HPV- tumors represent two unique biological and clinical entities with different treatment strategies. High-risk HPV subtypes encode oncoproteins E6 and E7 that disrupt cellular senescence and ultimately drive tumorigenesis. Current methods for detection of HPV take advantage of this established oncogenic pathway and detect HPV at various biological stages. This review article provides an overview of the existing technologies employed for the detection of HPV and their current or potential future role in management and prognostication.

Human Papillomavirus Infection in Head and Neck Squamous Cell Carcinomas: Transcriptional Triggers and Changed Disease Patterns

Head and neck squamous cell carcinoma (HNSCC) is a heterogeneous group of cancers. Collectively, HNSCC ranks sixth in incidence rate worldwide. Apart from classical risk factors like tobacco and alcohol, infection of human papillomavirus (HPV) is emerging as a discrete risk factor for HNSCC. HPV-positive HNSCC represent a distinct group of diseases that differ in their clinical presentation. These lesions are well-differentiated, occur at an early age, and have better prognosis. Epidemiological studies have demonstrated a specific increase in the proportions of the HPV-positive HNSCC. HPV-positive and HPV-negative HNSCC lesions display different disease progression and clinical response. For tumorigenic-transformation, HPV essentially requires a permissive cellular environment and host cell factors for induction of viral transcription. As the spectrum of host factors is independent of HPV infection at the time of viral entry, presumably entry of HPV only selects host cells that are permissive to establishment of HPV infection. Growing evidence suggest that HPV plays a more active role in a subset of HNSCC, where they are transcriptionally-active. A variety of factors provide a favorable environment for HPV to become transcriptionally-active. The most notable are the set of transcription factors that have direct binding sites on the viral genome. As HPV does not have its own transcription machinery, it is fully dependent on host transcription factors to complete the life cycle. Here, we review and evaluate the current evidence on level of a subset of host transcription factors that influence viral genome, directly or indirectly, in HNSCC. Since many of these transcription factors can independently promote carcinogenesis, the composition of HPV permissive transcription factors in a tumor can serve as a surrogate marker of a separate molecularly-distinct class of HNSCC lesions including those cases, where HPV could not get a chance to infect but may manifest better prognosis.

Human papilloma virus related squamous cell carcinomas of the head and neck: diagnosis, clinical implications and detection of HPV

High-risk human papillomavirus (HPV) positive squamous cell carcinoma (SCC) of the head and neck is reported most commonly in the oropharynx but can also uncommonly be found in other sites such as the anterior oral cavity and sinonasal tract. While HPV positive oropharyngeal squamous cell carcinoma (HPV-OPSCC) has been shown to have a more favourable prognosis than conventional smoking- and alcohol-related anterior oral cavity squamous cell carcinoma (OSCC), HPV positive SCC arising elsewhere in the head and neck region does not carry the same favourable prognosis. HPV-OPSCC often tends to present with large cystic metastases in the cervical lymph nodes, with a clinically and radiologically occult primary. Correct diagnosis of the initial biopsy/cytology specimen is critical for directing further investigations and management. In recognition of its distinct biological behaviour, the 8th edition of the American Joint Commission on Cancer (AJCC 8) has proposed a separate clinical and pathological staging system for HPV-OPSCC compared to that for a conventional primary OSCC or neck metastasis of similar size. The new AJCC staging does not apply to other HPV positive SCC of the head and neck. This review examines the current biology of HPV positive SCC, focusing on HPV-OPSCC. The value and pitfalls of current detection methods of HPV are discussed with an emphasis on the role of the pathologist in the diagnosis and management of HPV positive SCC of the head and neck.

CD47-SIRPα Signaling Induces Epithelial-Mesenchymal Transition and Cancer Stemness and Links to a Poor Prognosis in Patients with Oral Squamous Cell Carcinoma

Background: Oral squamous cell carcinoma (OSCC), with high mortality rates, is one of the most diagnosed head and neck cancers. Epithelial-to-mesenchymal transition (EMT) and the generation of cancer stem cells (CSCs) are two keys for therapy-resistance, relapse, and distant metastasis. Accumulating evidence indicates that aberrantly expressed cluster of differentiation (CD)47 is associated with cell-death evasion and metastasis; however, the role of CD47 in the generation of CSCs in OSCC is not clear. Methods: We investigated the functional roles of CD47 in OSCC cell lines SAS, TW2.6, HSC-3, and FaDu using the bioinformatics approach, immunoblotting, immunofluorescence staining, and assays for cellular migration, invasion, colony, and orosphere formation, as well as radiosensitivity. Results: We demonstrated increased expression of CD47 in OSCC patients was associated with an estimated poorly survival disadvantage (p = 0.0391) and positively correlated with the expression of pluripotency factors. Silencing CD47 significantly suppressed cell viability and orosphere formation, accompanied by a downregulated expression of CD133, SRY-Box transcription factor 2 (SOX2), octamer-binding transcription factor 4 (OCT4), and c-Myc. In addition, CD47-silenced OSCC cells showed reduced EMT, migration, and clonogenicity reflected by increased E-cadherin and decreased vimentin, Slug, Snail, and N-cadherin expression. Conclusion: Of therapeutic relevance, CD47 knockdown enhanced the anti-OSCC effect of radiotherapy. Collectively, we showed an increased CD47 expression promoted the generation of CSCs and malignant OSCC phenotypes. Silencing CD47, in combination with radiation, could provide an alternative and improved therapeutic efficacy for OSCC patients.

Protecting Tumors by Preventing Human Papilloma Virus Antigen Presentation: Insights from Emerging Bioinformatics Algorithms

Recent developments in bioinformatics technologies have led to advances in our understanding of how oncogenic viruses such as the human papilloma virus drive cancer progression and evade the host immune system. Here, we focus our review on understanding how these emerging bioinformatics technologies influence our understanding of how human papilloma virus (HPV) drives immune escape in cancers of the head and neck, and how these new informatics approaches may be generally applicable to other virally driven cancers. Indeed, these tools enable researchers to put existing data from genome wide association studies, in which high risk alleles have been identified, in the context of our current understanding of cellular processes regulating neoantigen presentation. In the future, these new bioinformatics approaches are highly likely to influence precision medicine-based decision making for the use of immunotherapies in virally driven cancers.

Proteomes of exosomes from HPV(+) or HPV(-) head and neck cancer cells: differential enrichment in immunoregulatory proteins

Human papillomavirus (HPV) is an etiologic factor in head and neck squamous cell carcinoma (HNSCC). HPV(+) cancers respond favorably to therapy potentially due to more robust anti-tumor immune responses. We hypothesized that tumor-derived exosomes (TEX) produced by HPV(+) or HPV(-) HNSCCs differentially modulate anti-tumor immune responses.

Proteomes of exosomes from HPV(+) and HPV(-) HNSCC cell lines were compared in search for proteins putatively involved in the communication with immune system. TEX were isolated from supernatants of HPV(+) (SCC-2, SCC-47, and SCC-90) or HPV(-) (PCI-13 and PCI-30) cells by size exclusion chromatography. A comparison of proteome profiles was performed by high-resolution mass spectrometry. The presence and biological activity of selected immunoregulatory proteins were validated by flow cytometry and co-incubation assays. Exosomes produced by SCC-90 and PCI-30 cells contained 711 proteins, including 80 proteins specific for HPV(+) exosomes and 77 specific for HPV(-) exosomes, associated with similar GO terms such as regulation of cell growth, metabolism, communication, and cellular signaling. Search for proteins localized in the membrane and involved in immune regulation identified a few proteins detected specifically in HPV(+) or HPV(-) exosomes. Only HPV(+) exosomes were enriched in immune effector cell-related CD47 and CD276 antigens; only HPV(-) exosomes contained tumor-protective/growth-promoting antigens, MUC-1 and HLA-DA. Flow cytometry and Western blots confirmed the reciprocal presence/paucity of these proteins in a whole panel of tumor cells and corresponding exosomes. The differential content of protein cargos in HPV(+) and HPV(-) exosomes might contribute to the disparity in immune responses that characterize HPV(+) and HPV(-) HNSCC.

HPV-Associated Oropharyngeal Cancer in the HIV/AIDS Patient

Since their discovery as the etiologic agents of cervical cancer in the mid-1970s, human papillomaviruses (HPVs) have been linked with a growing number of epithelial-derived tumors, including head and neck squamous cell carcinomas. HPV demonstrates a particular predilection for causing tumors of the oropharynx, with the majority of cases involving infection with high-oncogenic risk HPV-16. People living with HIV are at increased risk of infection with HPV- and HPV-related oral complications even with adequate control of their HIV infection with antiretroviral therapy. In this chapter, we discuss the molecular mechanisms that underlie HPV-mediated oncogenesis in the oropharynx. We also describe the progress that has been made in understanding the epidemiology of oral HPV infection and the determinants of oral HPV-related pathology. Finally, we examine what can be done to treat and prevent oral HPV infection, benign lesions, and cancer, particularly in the context of the HIV-positive patient.

Reviewing the role of human papillomavirus in oral cancer using the Bradford Hill criteria of causation

Human papillomavirus is a well-established risk factor for oropharyngeal cancer, although its role in oral cancer is still debated. Inconclusive evidence of its role in oral cancer is due to conflicting data arising from methodological differences, mostly due to the use of diagnostic tests with varying sensitivity and specificity. In addition, there is a lack of experimental data linking HPV to oral cancer. Recent epidemiological studies provide data on HPV prevalence in oral squamous cell carcinoma and other potentially malignant oral disorders. Further, molecular data from in vivo and in vitro models have led to new insights into the role of human papillomavirus in oral cancer. The clinical significance of identifying HPV as an etiology for oral squamous cell carcinoma is that if proven, vaccination could be an effective prevention tool. Further, like oropharyngeal squamous cell carcinoma, prognostic differences may exist between human papillomavirus positive and negative oral squamous cell carcinoma. This manuscript reviews data from the published literature using Bradford Hill criteria of causation to assess the role of human papillomavirus in oral cancer. Due to the advancement in molecular biology, the requirements of each of the Bradford Hill criteria of causation are modified to include integrated data from both epidemiological studies and experimental studies exploring molecular carcinogenesis.

Current status of clinical testing for human papillomavirus in oropharyngeal squamous cell carcinoma

While a variety of human papillomavirus (HPV) tests and surrogate markers are available, currently there is no consensus on the best detection method(s) that should be used to identify HPV-related oropharyngeal squamous cell carcinomas and serve as a standard test (or tests) for routine diagnostic use. As we begin to consider using the results of HPV testing for clinical purposes beyond simple prognostication, such as making decisions on treatment dose or duration or for targeted therapies that may be highly dependent on viral-mediated pathways, we need to be more rigorous in assessing and ensuring the performance of the test (or tests) used. Here we provide an overview of the platforms and technologies, including the strengths and limitations of each test, and discuss what steps are needed to generate confidence in their performance for use in clinical practice.

Head and Neck Cytopathology: Human Papillomavirus-Positive Carcinomas, Including Diagnostic Updates, Testing Modalities, and Recommendations

Oropharyngeal squamous cell carcinoma caused by transcriptionally active human papillomavirus (HPV) is now well established as a unique form of head and neck cancer. Given the high frequency of metastasis to cervical lymph nodes by HPV-positive oropharyngeal squamous cell carcinomas, fine-needle aspiration (FNA) represents a widely accepted method for the sampling and diagnosis of these cancers. The recently published College of American Pathologists Guideline (2017) provides recommendations for the effective performance and interpretation of high-risk (HR) HPV testing in head and neck squamous cell carcinoma (HNSCC), including testing on FNA samples of metastatic HNSCC to cervical lymph nodes. There is a wide range of options available for HR-HPV testing in cytologic specimens.

The molecular landscape of head and neck cancer

Head and neck squamous cell carcinomas (HNSCCs) arise in the mucosal linings of the upper aerodigestive tract and are unexpectedly heterogeneous in nature. Classical risk factors are smoking and excessive alcohol consumption, and in recent years, the role of human papillomavirus (HPV) has emerged, particularly in oropharyngeal tumours. HPV-induced oropharyngeal tumours are considered a separate disease entity, which recently has manifested in an adapted prognostic staging system while the results of de-intensified treatment trials are awaited. Carcinogenesis caused by HPV in the mucosal linings of the upper aerodigestive tract remains an enigma, but with some recent observations, a model can be proposed. In 2015, The Cancer Genome Atlas (TCGA) consortium published a comprehensive molecular catalogue on HNSCC. Frequent mutations of novel druggable oncogenes were not demonstrated, but the existence of a subgroup of genetically distinct HPV-negative head and neck tumours with favourable prognoses was confirmed. Tumours can be further subclassified based on genomic profiling. However, the amount of molecular data is currently overwhelming and requires detailed biological interpretation. It also became apparent that HNSCC is a disease characterized by frequent mutations that create neoantigens, indicating that immunotherapies might be effective. In 2016, the first results of immunotherapy trials with immune checkpoint inhibitors were published, and these may be considered as a paradigm shift in head and neck oncology.

Molecular and serologic markers of HPV 16 infection are associated with local recurrence in patients with oral cavity squamous cell carcinoma

Human papillomavirus (HPV) infections predict mortality in Taiwanese patients with oral cavity squamous cell carcinoma (OCSCC). To address their prognostic significance for local recurrence (LR), in this retrospective cohort study we investigated different serologic and molecular markers of HPV 16 infection in 85 consecutive patients with primary OCSCC who received standard treatment and had their sera stored before treatment. Resected tumor specimens were examined with PCR-based assays for HPV 16 E6/E7 mRNA expression. Sera were tested with suspension arrays for the presence of HPV-specific antibodies using synthetic L1 and E6 peptides as well as a synthetic E7 protein. HPV 16 E6/E7 mRNA, anti-L1, anti-E6, and anti-E7 antibodies tested positive in 12%, 25%, 38%, and 41% of the study patients, respectively. Multivariate analysis identified pathological T3/T4, E6/E7 mRNA, and anti-E7 antibodies as independent risk factors for LR, whereas anti-E6 antibodies were an independent protective factor. In patients with ≥ 3 (high-risk group), 2 (intermediate-risk), and ≤ 1 (low-risk) independent risk factors (predictors), the 5-year LR rates were 75%, 42%, and 4%, respectively. Results were validated in an independent cohort. Together, our preliminary data indicate that HPV 16 infections as well as low and high serum levels of anti-E6 and anti-E7 antibodies, respectively, can serve as biomarkers of LR in patients with OCSCC, whereas the clinical usefulness of anti-HPV 16 antibodies for risk stratification of newly diagnosed cases deserves further scrutiny.

High-risk HPV genotypes and P16INK4a expression in a cohort of head and neck squamous cell carcinoma patients in Singapore

Human papillomavirus (HPV), especially HPV16 genotype, is associated with oropharyngeal squamous cell carcinoma (OPSCC). We aim to determine the prevalence and characterize the high-risk (HR)-HPV genotypes in head and neck SCC (HNSCC) in a South-East Asian multi-ethnic society in Singapore and examine its prognostic significance.159 HNSCC archival tissue samples were retrieved and tumour DNA was screened for 18 HR-HPV genotypes using a PCR-based assay (Qiagen, digene HPV genotyping RH test). P16 protein overexpression was identified using immunohistochemistry (IHC). Statistical correlation between clinical outcomes were performed between HPV-positive and negative HNSCC patients.Six HR-HPVs (HPV16, 18, 31, 45, 56, 68) were detected in 90.6% of HNSCC; and 79.9% had multiple HPV genotypes detected. HPV31 and HPV45 were the most prevalent (79.2% and 87.4%, respectively); and HPV16 was predominantly found in OPSCC (p < 0.001). HPV-DNA PCR assay yielded a high sensitivity (96%) but low specificity (11%) when compared to p16 immunohistochemistry as the reference standard.P16-positive HNSCC was predominantly observed in OPSCC (73.7%; p = 0.005); and p16-positive OPSCC exhibited improved overall survival compared to p16-negative OPSCC (p = 0.022). Similarly, smoking and alcohol consumption were poor prognostic factors of overall survival (p = 0.007; p = 0.01) in OPSCC patients.HR-HPVs were identified in 90.6% of HNSCC patients using the HPV-DNA PCR assay. This test had a poor specificity when compared to p16 IHC; making it an unreliable detection technique in selecting patients for radiation dose de-escalation treatment protocol. P16-positive tumor was predominantly found in the oropharynx these patients demonstrated better overall survival than those with p16-negative OPSCC.

Detection of HPV E6/E7 mRNA in Clinical Samples Using RNA In Situ Hybridization

Detection of human papilloma virus (HPV) in tissue specimens has been a clinical challenge since last 2 decades; however, screening for presence of E6/E7 transcripts is regarded as the gold standard, and it verifies the active HPV infection. Here, we describe "RNAscope^® assay" a novel RNA in situ hybridization (ISH) technology; which detects E6/E7 mRNA of seven high risk HPV subtypes (HPV 16, 18, 31, 33, 35, 52, and 58) in formalin fixed paraffin embedded (FFPE) tissue samples.

Human papillomavirus and p16 protein expression as prognostic biomarkers in mobile tongue cancer

OBJECTIVES

The objectives were to determine the prevalence of human papillomavirus (HPV) in mobile tongue cancer (MTC) and evaluate associations and survival.

MATERIALS AND METHODS

Patients who underwent surgical resection as primary treatment for MTC (n = 127) were retrospectively evaluated. Formalin-fixed paraffin-embedded (FFPE) specimens were assessed for p16 and p53 by immunohistochemistry; for HPV DNA by nested multiplex polymerase chain reaction (PCR) using two pairs of consensus primers (MY09-MY11 and GP5+-GP6+); and for E6 and E7 oncogenes from 13 high-risk HPV types (16, 18, 31, 33, 35, 39, 45, 52, 56, 58, 59, 66, and 68) by real-time reverse transcription PCR (RT-PCR).

RESULTS

There were 18 (14.2%) p16-positive, 45 (35.4%) p53-positive, 9 (7.1%) HPV DNA-positive, and 7 (5.5%) E6 and/or E7 mRNA-positive tumors, but the correlation of all pairs was poor. There was no demographic or histopathologic association with HPV status. Cause-specific survival was significantly better with p16-positive than with p16-negative tumors (p = .037).

CONCLUSIONS

The prevalence of HPV and p16 positivity was relatively low and p16 status was a poor surrogate marker for HPV status. The results showed the importance of p16 expression in prognosticating mobile tongue cancer.

Molecular Patterns and Biology of HPV-Associated HNSCC

Head and neck cancer is the sixth most common cancer worldwide. The large majority are squamous cell carcinomas (HNSCC) that develop in the mucosal linings of the upper aerodigestive tract. These tumors develop either by exogenous carcinogen exposure (smoking, alcohol drinking) or by human papillomavirus (HPV) infection, particularly those in the oropharynx (OPSCC). HPV-positive (HPV+ve) and HPV-negative (HPV-ve) OPSCC are considered different disease entities. HPV+ve tumors are different at the molecular level and likely as a consequence have a much more favorable prognosis than HPV-ve tumors, despite their generally advanced stage at presentation. In general, HNSCCs develop in precancerous mucosal changes, and the apparent lack of precancerous HPV+ve mucosal changes is therefore remarkable. In this Chapter, head and neck carcinogenesis is discussed and the molecular differences between HPV+ve and HPV-ve tumors are outlined.

Telomeres and telomerase in head and neck squamous cell carcinoma: from pathogenesis to clinical implications

Strongly associated with tobacco use, heavy alcohol consumption, and with high-risk human papillomavirus (HPV) infection, head and neck squamous cell carcinoma (HNSCC) is a frequently lethal, heterogeneous disease whose pathogenesis is a multistep and multifactorial process involving genetic and epigenetic events. The majority of HNSCC patients present with locoregional advanced stage disease and are treated with combined modality strategies that can markedly impair quality of life and elicit unpredictable results. A large fraction of those who undergo locoregional treatment and achieve a complete response later develop locoregional recurrences or second field tumors. Biomarkers that are thus able to stratify risk and enable clinicians to tailor treatment plans and to personalize post-therapeutic surveillance strategies are highly desirable. To date, only HPV status is considered a reliable independent predictor of treatment response and survival in patients with HNSCC arising from the oropharyngeal site. Recent studies suggest that telomere attrition, which may be an early event in human carcinogenesis, and telomerase activation, which is detected in up to 90 % of malignancies, could be potential markers of cancer risk and disease outcome. This review examines the current state of knowledge on and discusses the implications linked to telomere dysfunction and telomerase activation in the development and clinical outcome of HNSCC.

Development of HPV Vaccines for HPV-associated Head and Neck Squamous Cell Carcinoma

High-risk genotypes of the human papillomavirus (HPV), particularly HPV type 16, are found in a distinct subset of head and neck squamous cell carcinomas (HNSCC). Thus, these HPV-associated HNSCC may be prevented or treated by vaccines designed to induce appropriate HPV virus-specific immune responses. Infection by HPV may be prevented by neutralizing antibodies specific for the viral capsid proteins. In clinical trials, vaccines comprised of HPV virus-like particles (VLPs) have shown great promise as prophylactic HPV vaccines. However, given that capsid proteins are not expressed at detectable levels by infected basal keratinocytes, vaccines with therapeutic potential must target other non-structural viral antigens. Two HPV oncogenic proteins, E6 and E7, are important in the induction and maintenance of cellular transformation and are co-expressed in the majority of HPV-containing carcinomas. Therefore, therapeutic vaccines targeting these proteins may have potential to control HPV-associated malignancies. Various candidate therapeutic HPV vaccines are currently being tested whereby E6 and/or E7 is administered in live vectors, in peptides or protein, in nucleic acid form, as components of chimeric VLPs, or in cell-based vaccines. Encouraging results from experimental vaccination systems in animal models have led to several prophylactic and therapeutic vaccine clinical trials. Should they fulfill their promise, these vaccines may prevent HPV infection or control its potentially life-threatening consequences in humans.

Human Papillomavirus Drives Tumor Development Throughout the Head and Neck: Improved Prognosis Is Associated With an Immune Response Largely Restricted to the Oropharynx

Purpose In squamous cell carcinomas of the head and neck (HNSCC), the increasing incidence of oropharyngeal squamous cell carcinomas (OPSCCs) is attributable to human papillomavirus (HPV) infection. Despite commonly presenting at late stage, HPV-driven OPSCCs are associated with improved prognosis compared with HPV-negative disease. HPV DNA is also detectable in nonoropharyngeal (non-OPSCC), but its pathogenic role and clinical significance are unclear. The objectives of this study were to determine whether HPV plays a causal role in non-OPSCC and to investigate whether HPV confers a survival benefit in these tumors. Methods Meta-analysis was used to build a cross-tissue gene-expression signature for HPV-driven cancer. Classifiers trained by machine-learning approaches were used to predict the HPV status of 520 HNSCCs profiled by The Cancer Genome Atlas project. DNA methylation data were similarly used to classify 464 HNSCCs and these analyses were integrated with genomic, histopathology, and survival data to permit a comprehensive comparison of HPV transcript-positive OPSCC and non-OPSCC. Results HPV-driven tumors accounted for 4.1% of non-OPSCCs. Regardless of anatomic site, HPV+ HNSCCs shared highly similar gene expression and DNA methylation profiles; nonkeratinizing, basaloid histopathological features; and lack of TP53 or CDKN2A alterations. Improved overall survival, however, was largely restricted to HPV-driven OPSCCs, which were associated with increased levels of tumor-infiltrating lymphocytes compared with HPV-driven non-OPSCCs. Conclusion Our analysis identified a causal role for HPV in transcript-positive non-OPSCCs throughout the head and neck. Notably, however, HPV-driven non-OPSCCs display a distinct immune microenvironment and clinical behavior compared with HPV-driven OPSCCs.

Diagnosis of HPV driven oropharyngeal cancers: Comparing p16 based algorithms with the RNAscope HPV-test

BACKGROUND

Accurate identification of HPV-driven oropharyngeal cancer (OPC) is a major issue and none of the current diagnostic approaches is ideal. An in situ hybridization (ISH) assay that detects high-risk HPV E6/E7 mRNA, called the RNAscope HPV-test, has been recently developed. Studies have suggested that this assay may become a standard to define HPV-status.

METHODS

To further assess this test, we compared its performance against the strategies that are used in routine clinical practice: p16 immunohistochemistry (IHC) as a single test and algorithms combining p16-IHC with HPV-DNA identification by PCR (algorithm-1) or ISH (algorithm-2).

RESULTS

105 OPC specimens were analyzed. The prevalence of HPV-positive samples varied considerably: 67% for p16-IHC, 54% for algorithm-1, 61% for algorithm-2 and 59% for the RNAscope HPV-test. Discrepancies between the RNAscope HPV-test and p16-IHC, algorithm-1 and 2 were noted in respectively 13.3%, 13.1%, and 8.6%. The 4 diagnostic strategies were able to identify 2 groups with different prognosis according to HPV-status, as expected. However, the greater survival differential was observed with the RNAscope HPV-test [HR: 0.19, 95% confidence interval (CI), 0.07-0.51, p=0.001] closely followed by algorithm-1 (HR: 0.23, 95% CI, 0.08-0.66, p=0.006) and algorithm-2 (HR: 0.26, 95% CI, 0.1-0.65, p=0.004). In contrast, a weaker association was found when p16-IHC was used as a single test (HR: 0.33, 95% CI, 0.13-0.81, p=0.02).

CONCLUSIONS

Our findings suggest that the RNAscope HPV-test and p16-based algorithms perform better that p16 alone to identify OPC that are truly driven by HPV-infection. The RNAscope HPV-test has the advantage of being a single test.

Human Papilloma Virus in Oral Cavity Cancer and Relation to Change in Quality of Life Following Treatment-a Pilot Study from Northern India

Human papilloma virus (HPV)-associated head and neck cancer (HNC) has generated significant amount of research interest in recent times with focus shifted to oral cavity squamous cell cancer (OCSCC) after oropharyngeal cancer. Due to high incidence of OCSCC and anecdotal reports on association of HPV infection from northern region of India, this study was conceived to investigate HPV infection and establish its association with lifestyle habits such as tobacco, alcohol consumption, oro-genital sex, number of sexual contacts, and change in quality of life posttreatment. A total of 43 primary OCSCC biopsy specimens were collected. These samples were analyzed for HPV DNA genotyping which was done by using 13 high-risk HPV real-time PCR kits. Quality of life was assessed using University of Washington questionnaire for HNC patients, which was administered pretreatment and 3-months posttreatment. HPV presence was confirmed in only three patients (7.0 %). HPV positivity did not find any statistical correlation with age, gender, residence, addiction habit, stage, tumor size, nodal status, tumor grade, and number of sexual contacts. There was no significant (p > 0.05) difference in the average percent change in QOL parameters from pretreatment to posttreatment when correlated with HPV status.

Human papillomavirus as a favorable prognostic factor in a subset of head and neck squamous cell carcinomas: A meta-analysis

Many epidemical and biological studies have proposed that human papillomavirus (HPV), primarily high-risk HPV16/18, is an etiological factor for a subset of head and neck (HN) cancers. On that premise, we systematically reviewed relevant articles and improved the understanding of HPV-related cancers. This article comprehensively described the characteristics of HPV-associated HN tumors according to demography, histopathology, molecular biology, and prognosis. Meta-analyses were conducted to combine the studies that reported the association between HPV status and these variables using Rev Man 5.0. The pooled results showed that HPV-positive tumors were not only poorly differentiated (OR = 2.77, 95% CI: 2.3-3.32) and smaller (OR = 2.21, 95% CI: 1.75-2.8) but were also strongly associated with oropharynx (OR = 5.8, 95% CI: 4.01-8.38) and node involvement (OR = 2.77, 95% CI: 2.3-3.32). HPV-related tumors showed significantly more p16 overexpression (OR = 34.55, 95% CI: 20.91-57.09) and less TP53 mutations (OR = 0.27, 95% CI: 0.18-0.41) than HPV-negative tumors. The patients with HPV-positive cancers had different clinical behaviors, such as a reduced risks of death (HR = 0.32, 95% CI: 0.29-0.36). This study supported the view point that HPV is a favorable indicator of prognosis and that HPV-related HN tumors are distinct from traditional tumors. This etiological relationship could impact future strategies of diagnosis, prevention, therapy, and prognosis for this subset of patients. J. Med. Virol. 89:710-725, 2017. © 2016 Wiley Periodicals, Inc.

Investigation into the presence of human papillomavirus in patients with obstructive sleep apnea

OBJECTIVES/HYPOTHESIS

The human papillomavirus (HPV) is known to infect the tissues of the oropharynx as demonstrated in HPV-positive oropharyngeal squamous cell carcinoma (OPSCC). HPV has also been shown to induce benign lymphoid hypertrophy. We sought to investigate an association between obstructive sleep apnea (OSA) and the presence of HPV in palatine and lingual tonsillar oropharyngeal tissue.

STUDY DESIGN

Case series with chart review.

METHODS

This retrospective laboratory-based study of oropharyngeal tissue from patients with OSA included patients >18 years old who underwent surgical treatment for OSA at a single institution between January 2012 and May 2014. Surgical specimens of adequate size were analyzed for HPV6, 11, and 16 using real-time quantitative polymerase chain reaction from DNA extracted from formalin-fixed paraffin-embedded tissue blocks. Student t test, Pearson χ² test, and linear logistic regression were used to assess comparisons of body mass index (BMI), apnea-hypopnea index (AHI), age, and gender between HPV-positive and HPV-negative groups.

RESULTS

Of 99 cases included in the study, six were positive for HPV: two with HPV16 and four with HPV6. BMI, AHI, age, and gender showed no significant differences between the HPV-positive and HPV-negative groups. Logistic regression to predict HPV positivity accounting for each variable and multivariate analysis were not statistically significant.

CONCLUSIONS

Our study did not show HPV to have a statistically significant association with OSA. None of the covariates analyzed (BMI, AHI, gender, age) predicted HPV positivity in surgically resected oropharyngeal tissue from OSA patients.

LEVEL OF EVIDENCE

4 Laryngoscope, 127:1231-1234, 2017.

The Expression Levels of XLF and Mutant P53 Are Inversely Correlated in Head and Neck Cancer Cells

XRCC4-like factor (XLF), also known as Cernunnos, is a protein encoded by the human NHEJ1 gene and an important repair factor for DNA double-strand breaks. In this study, we have found that XLF is over-expressed in HPV(+) versus HPV(-) head and neck squamous cell carcinoma (HNSCC) and significantly down-regulated in the HNSCC cell lines expressing high level of mutant p53 protein versus those cell lines harboring wild-type TP53 gene with low p53 protein expression. We have also demonstrated that Werner syndrome protein (WRN), a member of the NHEJ repair pathway, binds to both mutant p53 protein and NHEJ1 gene promoter, and siRNA knockdown of WRN leads to the inhibition of XLF expression in the HNSCC cells. Collectively, these findings suggest that WRN and p53 are involved in the regulation of XLF expression and the activity of WRN might be affected by mutant p53 protein in the HNSCC cells with aberrant TP53 gene mutations, due to the interaction of mutant p53 with WRN. As a result, the expression of XLF in these cancer cells is significantly suppressed. Our study also suggests that XLF is over-expressed in HPV(+) HNSCC with low expression of wild type p53, and might serve as a potential biomarker for HPV(+) HNSCC. Further studies are warranted to investigate the mechanisms underlying the interactive role of WRN and XLF in NHEJ repair pathway.

Low prevalence of transcriptionally active human papilloma virus in Indian patients with HNSCC and leukoplakia

OBJECTIVES

In the present study, we comprehensively analyzed the prevalence of transcriptionally active human papilloma virus (HPV) in tissue samples of Indian patients with leukoplakia, predominantly hyperplastic lesions and head and neck squamous cell carcinoma (HNSCC). In addition, saliva samples from patients with HNSCC were screened for HPV detection.

STUDY DESIGN

P16 overexpression was analyzed by immunohistochemistry. Tissue samples of leukoplakia (n = 121) and HNSCC (n = 427) and saliva from patients with HNSCC (n = 215) were tested for HPV using nested polymerase chain reaction. Positive samples were sequenced for subtyping. The presence of HPV E6/E7 mRNA was confirmed by RNA in situ hybridization.

RESULTS

P16 expression and HPV DNA were not detected in any of the leukoplakia specimens. Of the 427 HNSCC tumors, 9 showed p16 overexpression and 7/427 cases were positive for HPV16 DNA, in saliva or tissue. E6/E7 mRNA positivity was observed in 8 HNSCC samples, primarily from patients with no habit of tobacco consumption. The prevalence of high-risk HPV was restricted to oropharynx and larynx, with very little concordance between p16 overexpression and HPV positivity. All patients with HPV-positive saliva samples had transcriptionally active HPV present in their tumors.

CONCLUSION

The presence of HPV DNA does not necessarily reflect transcriptionally active virus in tumors; hence, it is important to consider this fact while categorizing HPV-associated tumors.

Automated Extraction of Formalin-Fixed, Paraffin-Embedded Tissue for High-Risk Human Papillomavirus Testing of Head and Neck Squamous Cell Carcinomas Using the Roche Cobas 4800 System

CONTEXT

-Testing for high-risk human papillomavirus (HR-HPV) in head and neck squamous cell carcinomas (HNSCCs) is important for both prognostication and clinical management. Several testing platforms are available for HR-HPV; however, effective alternative automated approaches are needed.

OBJECTIVE

-To assess the performance of the automated Roche cobas 4800 HPV real-time polymerase chain reaction-based system on formalin-fixed, paraffin-embedded HNSCC specimens and compare results with standard methods of in situ hybridization (ISH) and p16 immunohistochemistry.

DESIGN

-Formalin-fixed, paraffin-embedded samples of HNSCC were collected from archival specimens in the Department of Pathology, Massachusetts General Hospital (Boston), and prepared using the automated system by deparaffinization and dehydration followed by tissue lysis. Samples were integrated into routine cervical cytology testing runs by cobas. Corresponding formalin-fixed, paraffin-embedded samples were evaluated for HR-HPV by ISH and p16 by immunohistochemistry. Discrepant cases were adjudicated by polymerase chain reaction.

RESULTS

-Sixty-two HNSCC samples were analyzed using the automated cobas system, ISH, and immunohistochemistry. Fifty-two percent (n = 32 of 62) of formalin-fixed, paraffin-embedded tumors were positive for HR-HPV by cobas. Eighty-eight percent (n = 28 of 32) of cases were the HPV 16 subtype and 12% (n = 4 of 32) were other HR-HPV subtypes. Corresponding testing with ISH was concordant in 92% (n = 57 of 62) of cases. Compared with the adjudication polymerase chain reaction standard, there were 3 false-positive cases by cobas.

CONCLUSIONS

-Concordance in HNSCC HR-HPV status between cobas and ISH was more than 90%. The cobas demonstrated a sensitivity of 100% and a specificity of 91% for detection of HR-HPV. Advantages favoring cobas include its automation, cost efficiency, objective results, and ease of performance.

E1 detection as prognosticator in human papillomavirus-positive head and neck cancers

PURPOSE

HPV-related locally advanced head and neck cancers (LA-HNCs) show a good prognosis. This study aimed to investigate the HPV prevalence in LA-HNCs and compare the prognostic value of E1, E6 and L1 genomic viral fragments and p16, individually and in combination, in order to find the best prognosticator in terms of overall survival (OS) and progression-free survival (PFS).

PATIENTS AND METHODS

HPV16 was searched in 255 LA-HNC formalin-fixed paraffin-embedded tumor tissues, 89 oropharyngeal cancers (OPCs), and 166 non-OPCs by DNA-PCR with 3 primer pairs. p16 was analyzed by immunohistochemistry in 235 patients.

RESULTS

The prevalence of positive samples decreased constantly from E6 to L1 and E1 in both OPCs and non-OPCs. Each LA-HNC patient highlighted variable positivity for each fragment. OPCs showed a higher prevalence of positive samples compared to non-OPCs.Positive coexistence of all the fragments was more common in OPCs (31.5%) than non-OPCs (4.2%), and E1 detection was always associated with E6 and L1. E1-positive OPCs showed improved OS (p = 0.012) and PFS (p = 0.036), while L1- or E6-positive ones did not. p16-positive patients were more prevalent in the OPC (29.8%) than the non-OPC group (7.3%) (p&lt;0.0001) and its prognostic value was not superior to that of E1. However, the multivariate Cox analysis which included E1, L1, E6 status and p16 expression did not show a significant p value.

CONCLUSIONS

Though HPV16 positivity measured by DNA-PCR was higher for L1 and E6, they performed weakly as prognosticators; E1 might become a strong prognostic marker for OS and PFS in OPCs.

Performance of a Branch Chain RNA In Situ Hybridization Assay for the Detection of High-risk Human Papillomavirus in Head and Neck Squamous Cell Carcinoma

High-risk human papillomavirus (HR-HPV) is a major etiologic agent in a subset of head and neck squamous cell carcinomas (HNSCCs), and its recognition has prognostic and predictive implications. The availability of a sensitive and specific test to assess HR-HPV status is limited. We evaluate an RNA in situ hybridization (ISH) method using branch chain technology to detect HR-HPV and compare its results with DNA ISH, p16 immunohistochemistry, and polymerase chain reaction (PCR). Tissue sections from 54 patients were stained with a manual RNA ISH assay (ViewRNA), which detects 14 HR-HPV types, an automated DNA ISH assay, and p16 immunohistochemistry. Most cases (83%, n=45) were also tested on an automated platform for 14 HR-HPV types and 1 limited to HPV 16/18. PCR was performed in all cases and was successful in 93% (n=50). The RNA ISH assay produced results in 96% of the cases with strong signals and was easily interpreted. HR-HPV was detected in more cases (63%, n=34) by RNA ISH than by DNA ISH (39%, n=21). Compared with PCR, both ISH platforms were 94% specific. RNA ISH was more sensitive (91%) than DNA ISH (65%), and RNA ISH correlated more strongly with p16 immunostaining. HPV 16 represented 89% of HR-HPV detected. The cocktail HPV 16/18 platform was concordant with the pooled HR-HPV assay in all expected cases. The automated assay demonstrated high concordance (96%) with the manual version, showed decreased background, and should allow for easy implementation into the workflow of the diagnostic pathology laboratory.

HPV and cancer of the oral cavity

Increased awareness of human papillomavirus (HPV) as an etiological cause of head and neck squamous cell carcinoma has increased the interest in analysis of distinct oral sub-sites. It is currently under debate, whether HPV plays a role in the development of squamous cell carcinoma of the oral cavity (OSCC). The weakness in most published studies is the lack of performing different HPV detection tests combined with analysis for biological activity of the virus. In addition, different sub-sites of the oral cavity had been combined to a single entity, which retrospectively leads to a highly heterogeneous basis of data. In this review we mainly discuss the unclear role of HPV in OSCC development.

Applications of molecular diagnostics for personalized treatment of head and neck cancer: state of the art

Squamous cell carcinomas of the head and neck are the sixth most frequent tumors worldwide. Risk factors are carcinogenic exposure, infection with the human papillomavirus (HPV) and genetic predisposition. Lymph node metastasis in the neck and HPV status are major prognostic factors. There are several important clinical challenges that determine the research agenda in head and neck cancer. The first is more accurate staging, particularly of occult metastatic lymph nodes in the neck. A second challenge is the lack of biomarkers for personalized therapy. There are a number of treatment modalities that can be employed both single and in combination, but at present only site and stage of the tumor are used for treatment planning. Provided here is an overview of the successes and failures of molecular diagnostic approaches that have been and are being evaluated to address these clinical challenges.

Diagnosis of HPV-driven head and neck cancer with a single test in routine clinical practice

Accurate screening of HPV-driven head and neck squamous cell carcinoma is a critical issue. Although there are commercial direct and indirect assays for HPV-related head and neck squamous cell carcinoma, none are ideal. Recently, a novel RNA in situ hybridization test (the RNAscope HPV-test) has been developed for the detection of high-risk HPV E6/E7 mRNA in formalin-fixed paraffin-embedded tissue. However, validation of this assay against the 'gold standard' (identification of high-risk HPV E6/E7 mRNA in fresh-frozen tissue by quantitative real-time (qRT)-PCR) has only been reported by one team. Formalin-fixed paraffin-embedded samples from 50 patients with tonsil or tongue base carcinoma were tested using the RNAscope HPV-test, p16 immunohistochemistry, and chromogenic in situ hybridization for high-risk HPV-DNA. The results were compared with those of qRT-PCR on matched fresh-frozen samples. Compared with the reference test, the sensitivity, specificity, positive, and negative predictive values of the RNAscope HPV-test and of p16 immunohistochemistry were 93%, 94%, 96%, 88% and 96%, 93%, 96%, and 93%, respectively. Five cases were discrepant between the RNAscope HPV-test and p16-immunohistochemisrty. The RNAscope HPV-test demonstrated excellent analytical performance against the 'gold standard' and is easier to interpret than chromogenic in situ hybridization. p16-immunohistochemistry also performed very well, however its main weakness is that it is an indirect marker of the presence of HPV. These data suggest that the RNAscope HPV-test is a promising test that could be developed as a clinical standard for the precise identification of HPV-driven oropharyngeal squamous cell carcinoma.

Human papillomavirus infection on initiating synchronous esophageal neoplasia in patients with head and neck cancer

OBJECTIVES/HYPOTHESIS

Human papillomavirus (HPV) is a risk factor for head and neck squamous cell carcinoma (HNSCC) as well as esophageal squamous cell carcinoma (ESCC). We aimed to investigate whether HPV infection underlies the field cancerization phenomenon over upper aerodigestive tract to develop synchronous multiple cancers.

STUDY DESIGN

A case control study.

METHODS

The presence and subtype of HPV-DNA sequence in cancers were examined by polymerase chain reaction and sequencing in a prospective cohort with 100 HNSCCs, 50 of which had synchronous ESCCs. The clinicopathologic characteristics were further analyzed according to the presence of HPV.

RESULTS

Twelve patients were HPV-positive, of which 11 were positive for HPV-16. The prevalence of HPV infection were not different between the synchronous and HNSCC alone groups (P = 0.357). Testing for HPV in paired HNSCC and ESCC tissues from the same patient revealed that none were concomitantly HPV-positive. Multivariate logistic regression showed drinking alcohol (odds ratio [OR], 18.75; P = 0.030), alcohol flushing (OR, 2.53; P = 0.041), and body mass index (OR, 0.77; P = 0.001) but not HPV infection were independent risk factors for synchronous phenotype. The patients with synchronous ESCCs had significantly poorer survival than those with HNSCC alone (5-year overall survival: 30% vs. 70%; log-rank P < 0.001). However, patients with HPV-positive HNSCC tend to have favorable outcome than those with HPV-negative HNSCC.

CONCLUSIONS

HPV infection plays little role in field cancerization phenomenon to initiate synchronous SCC. The synchronous HNSCC and ESCC from the same patients had no clonal relationship. Routine endoscopic examination of the esophagus should be recommended for patients with risk factors identified.

LEVELS OF EVIDENCE

NA. Laryngoscope, 126:1097-1102, 2016.