Human papillomavirus 16 E6 antibodies are sensitive for human papillomavirus-driven oropharyngeal cancer and are associated with recurrence

The Next Chapter in Cancer Diagnostics: Advances in HPV-Positive Head and Neck Cancer

Human papillomavirus (HPV)-associated head and neck squamous cell carcinoma (HNSCC), particularly oropharyngeal squamous cell carcinoma (OPSCC), is an increasingly prevalent pathology worldwide, especially in developed countries. For diagnosing HPV in HNSCC, the combination of p16 immunohistochemistry (IHC) and polymerase chain reaction (PCR) offers high sensitivity and specificity, with p16 IHC being a reliable initial screen and PCR confirming HPV presence. Advanced techniques like next-generation sequencing (NGS) and RNA-based assays provide detailed insights but are primarily used in research settings. Regardless of HPV status, standard oncological treatments currently include surgery, radiation, and/or chemotherapy. This conventional approach does not account for the typically better prognosis of HPV-positive HNSCC patients, leading to increased chemo/radiation-induced secondary morbidities and reduced quality of life. Therefore, it is crucial to identify and detect HPV positivity and other molecular characteristics of HNSCC to personalize treatment strategies. This comprehensive review aims to summarize current knowledge on various HPV detection techniques and evaluate their advantages and disadvantages, with a focus on developing methodologies to identify new biomarkers in HPV-positive HNSCC. The review discusses direct and indirect HPV examination in tumor tissue, DNA- and RNA-based detection techniques, protein-based markers, liquid biopsy potentials, immune-related markers, epigenetic markers, novel biomarkers, and emerging technologies, providing an overall insight into the current state of knowledge.

The molecular characteristics of recurrent/metastatic HPV-positive head and neck squamous cell carcinoma: A systematic review of the literature

OBJECTIVES

About 17% of patients with human papillomavirus (HPV)-positive head and neck squamous cell carcinoma (HNSCC), which is mainly comprised of oropharyngeal SCC (OPSCC), will experience disease recurrence, which is often considered incurable when manifested at a metastatic and/or recurrent stage. We conducted a critical qualitative systematic review. Our objectives were to provide an overview of the molecular landscape of recurrent/metastatic HPV-positive HNSCC as well as novel molecular biomarkers.

DESIGN

A literature review was conducted to identify studies reporting on the molecular characteristics of recurrent/metastatic HPV-positive HNSCC, novel molecular biomarkers and treatment options. The reviews of abstracts, full articles, and revision of the included studies, followed by data extraction and quality assessment were performed by three independent assessors. All primary literature, such as retrospective, prospective, and clinical trials as well as basic research studies were considered, and the final search was conducted at the end of February 2023. The level of evidence was rated using the guidelines published by the Oxford Centre for Evidence-based Medicine and quality was assessed using the Newcastle-Ottawa Scale criteria.

RESULTS AND CONCLUSIONS

The literature search resulted in the identification of 1991 articles. A total of 181 full articles were screened, and 66 articles were included in this analysis. Several studies reported that recurrent/metastatic HPV-positive HNSCC had higher rates of TP53 mutation and were genomically similar to HPV-negative HNSCC. The detection of circulating tumour tissue-modified HPV DNA (ctHPVDNA) as a specific biomarker has shown promising results for monitoring treatment response and recurrence in the subset of HPV-positive HNSCC. In addition, evidence for targeted therapy in recurrent/metastatic HPV-positive HNSCC has emerged, including agents that inhibit overexpressed EGFR. Studies of combination immunotherapy are also underway. Our review outlines the latest evidence on the distinct molecular profiles of recurrent/metastatic HPV-positive HNSCC as well as the clinical potential of ctHPVDNA testing in routine practice. More controlled and longitudinal studies are needed to identify additional molecular targets and to assess the performance and benefits of novel molecular biomarkers in clinical practice.

Assessing the feasibility of a multimodal liquid biopsy for the diagnosis of HPV-associated oropharyngeal squamous cell carcinoma

OBJECTIVES

In this feasibility study, we explored the combined use of circulating tumor human papillomavirus (HPV) DNA (ctHPVDNA) and HPV serology as diagnostic tests for HPV-associated oropharyngeal squamous cell carcinoma (OPSCC).

METHODS

Among patients with research-banked serum or plasma at diagnosis, IgG antibodies to oncoproteins from HPV types 16, 18, 31, 33, 35, 45, 52, and 58 were detected with multiplex serology. Positivity for HPV 16 was defined based on detection of combinations of anti-E6, E1, E2, and E7 and for other high-risk types on detection of anti-E6 and anti-E7. Circulating tumor HPV DNA was detected by custom digital droplet polymerase chain reaction (ddPCR) assays for HPV types 16, 18, 33, 35, and 45. p16 immunohistochemistry and high-risk HPV RNA in situ hybridization (ISH) using a cocktail of 18 high-risk HPV types were performed on tissue.

RESULTS

Of 75 patients, 67 (89.3%) were HPV-associated (p16 and HPV RNA ISH positive) and 8 (10.7%) were HPV-independent. All 8 HPV-independent patients were seronegative and negative for ctHPVDNA (100% specificity). Serology was positive in 53 (79.1%) of 67 HPV-associated patients, while ddPCR was positive for ctHPVDNA in 59 (88.6%) of 67 HPV-associated patients. Requiring both tests to be positive resulted in a sensitivity of 50 (74.6%) of 67 while combining assays (either positive) improved sensitivity to 62 (92.6%) of 67.

CONCLUSIONS

Compared to HPV RNA ISH, HPV serology and ctHPVDNA are sensitive and highly specific biomarkers for HPV-associated OPSCC at the time of presentation.

Current and Emerging Diagnostic, Prognostic, and Predictive Biomarkers in Head and Neck Cancer

Head and neck cancers (HNC) are a biologically diverse set of cancers that are responsible for over 660,000 new diagnoses each year. Current therapies for HNC require a comprehensive, multimodal approach encompassing resection, radiation therapy, and systemic therapy. With an increased understanding of the mechanisms behind HNC, there has been growing interest in more accurate prognostic indicators of disease, effective post-treatment surveillance, and individualized treatments. This chapter will highlight the commonly used and studied biomarkers in head and neck squamous cell carcinoma.

B cells in head and neck squamous cell carcinoma: current opinion and novel therapy

Head and neck squamous cell carcinoma (HNSCC) is a common malignant tumour. Despite advancements in surgery, radiotherapy and chemotherapy, which have improved the prognosis of most patients, a subset of patients with poor prognoses still exist due to loss of surgical opportunities, postoperative recurrence, and metastasis, among other reasons. The tumour microenvironment (TME) is a complex organization composed of tumour, stromal, and endothelial cells. Communication and interaction between tumours and immune cells within the TME are increasingly being recognized as pivotal in inhibiting or promoting tumour development. Previous studies on T cells in the TME of HNSCC have yielded novel therapeutic possibilities. However, the function of B cells, another adaptive immune cell type, in the TME of HNSCC patients has yet to be determined. Recent studies have revealed various distinct subtypes of B cells and tertiary lymphoid structures (TLSs) in the TME of HNSCC patients, which are believed to impact the efficacy of immune checkpoint inhibitors (ICIs). Therefore, this paper focuses on B cells in the TME to explore potential directions for future immunotherapy for HNSCC.

Diagnostic accuracy of HPV16 early antigen serology for HPV-driven oropharyngeal cancer is independent of age and sex

A growing proportion of head and neck cancer (HNC), especially oropharyngeal cancer (OPC), is caused by human papillomavirus (HPV). There are several markers for HPV-driven HNC, one being HPV early antigen serology. We aimed to investigate the diagnostic accuracy of HPV serology and its performance across patient characteristics. Data from the VOYAGER consortium was used, which comprises five studies on HNC from North America and Europe. Diagnostic accuracy, that is, sensitivity, specificity, Cohen's kappa and correctly classified proportions of HPV16 E6 serology, was assessed for OPC and other HNC using p16INK4a immunohistochemistry (p16), HPV in situ hybridization (ISH) and HPV PCR as reference methods. Stratified analyses were performed for variables including age, sex, smoking and alcohol use, to test the robustness of diagnostic accuracy. A risk-factor analysis based on serology was conducted, comparing HPV-driven to non-HPV-driven OPC. Overall, HPV serology had a sensitivity of 86.8% (95% CI 85.1-88.3) and specificity of 91.2% (95% CI 88.6-93.4) for HPV-driven OPC using p16 as a reference method. In stratified analyses, diagnostic accuracy remained consistent across sex and different age groups. Sensitivity was lower for heavy smokers (77.7%), OPC without lymph node involvement (74.4%) and the ARCAGE study (66.7%), while specificity decreased for cases with <10 pack-years (72.1%). The risk-factor model included study, year of diagnosis, age, sex, BMI, alcohol use, pack-years, TNM-T and TNM-N stage. HPV serology is a robust biomarker for HPV-driven OPC, and its diagnostic accuracy is independent of age and sex. Future research is suggested on the influence of smoking on HPV antibody levels.

Liquid Biopsies with Circulating Plasma HPV-DNA Measurements-A Clinically Applicable Surveillance Tool for Patients with HPV-Positive Oropharyngeal Cancer

PURPOSE

To evaluate the accuracy of cell-free human papillomavirus-DNA (cfHPV-DNA) measurements in liquid biopsies in predicting disease in patients with HPV-positive/p16-positive (HPV+/p16+) oropharyngeal squamous cell carcinoma (OPSCC).

EXPERIMENTAL DESIGN

This was a prospective cohort study. Plasma samples were collected before treatment, serially after curative intended therapy at follow-up visits 2 weeks, and 6, 9, 12, 18, 24, and 30 months after treatment. A droplet digital PCR assay comprising eight HPV genotypes was used. HPV genotypes found in plasma and tumor tissue were compared. We correlated biopsy- or imaging-verified tumor progression to cfHPV-DNA in follow-up samples.

RESULTS

We enrolled 72 patients with HPV+/p16+ OPSCC. Baseline sensitivity for cfHPV-DNA detection was 97.2% (95% confidence interval, 90.3%-99.6%). CfHPV-DNA copy number/milliliter plasma correlated with tumor stage. We found a 100% concordance between HPV genotype in tumor tissue and plasma. Fifty-four patients were followed with serial blood samples for a median of 19.7 months (interquartile range, 13.5-25.5 months). Forty-one patients had undetectable plasma cfHPV-DNA in all follow-up samples, and none developed recurrences. Thirteen patients were classified as cfHPV-DNA-positive in a follow-up plasma sample. Of these, five patients developed a recurrence, and three had residual cancer. It was possible to detect cfHPV-DNA in plasma 97 to 166 days prior to the proven recurrence.

CONCLUSIONS

To our knowledge, to date, our study, comprising the largest study of patients with HPV+/p16+ OPSCC, using an ultrasensitive multiplex HPV gene panel, revealed a high sensitivity of cfHPV-DNA detection in the liquid biopsies. We recommend serial plasma HPV samples for clinical monitoring of patients with HPV+/p16+ OPSCC.

Peripheral surrogates of tumor burden to guide chemotherapeutic and immunotherapeutic strategies for HPV-associated malignancies

With the rapid adoption of immunotherapy into clinical practice for HPV-associated malignancies, assessing tumor burden using "liquid biopsies" would further our understanding of clinical outcomes mediated by immunotherapy and allow for tailoring of treatment based on real-time tumor dynamics. In this review, we examine translational studies on peripheral surrogates of tumor burden derived from peripheral blood in HPV-associated malignancies, including levels and methylation of circulating tumor DNA (ctDNA), miRNA derived from extracellular vesicles, circulating tumor cells (CTCs), and HPV-specific antibodies and T cell responses. We review their utility as prognostic and predictive biomarkers of response to chemotherapy and radiation, with a focus on how they may inform and guide immunotherapies to treat locally advanced and metastatic HPV-associated malignancies. We also highlight unanswered questions that must be addressed to translate and integrate these peripheral tumor biomarkers into the clinic.

The Tumor-Specific Immune Landscape in HPV+ Head and Neck Cancer

Human papillomaviruses (HPVs) are the causative agent of several anogenital cancers as well as head and neck cancers, with HPV+ head and neck squamous cell carcinoma (HNSCC) becoming a rapidly growing public health issue in the Western world. Due its viral etiology and potentially its subanatomical location, HPV+ HNSCC exhibits an immune microenvironment which is more inflamed and thus distinct from HPV-negative HNSCC. Notably, the antigenic landscape in most HPV+ HNSCC tumors extends beyond the classical HPV oncoproteins E6/7 and is extensively targeted by both the humoral and cellular arms of the adaptive immune system. Here, we provide a comprehensive overview of HPV-specific immune responses in patients with HPV+ HNSCC. We highlight the localization, antigen specificity, and differentiation states of humoral and cellular immune responses, and discuss their similarities and differences. Finally, we review currently pursued immunotherapeutic treatment modalities that attempt to harness HPV-specific immune responses for improving clinical outcomes in patients with HPV+ HNSCC.

How to prevent human papillomavirus-related oropharyngeal cancer?

PURPOSE OF REVIEW

Human papillomavirus (HPV) is responsible of the increasing incidence rates of oropharyngeal squamous cell carcinoma (OPSCC) in high-income countries. This significant epidemiological change requires several and diverse prevention strategies.

RECENT FINDINGS

The cervical cancer prevention model is the paradigm of HPV-related cancer, and its success provides encouragement for the development of similar methods to prevent HPV-related OPSCC. However, there are some limitations that hinder its application in this disease. Here, we review the primary, secondary and tertiary prevention of HPV-related OPSCC and discuss some directions for future research.

SUMMARY

The development of new and targeted strategies to prevent HPV-related OPSCC is needed since they could definitely have a direct impact on the reduction of morbidity and mortality of this disease.

Regulation of innate immune system function by the microbiome: Consequences for tumor immunity and cancer immunotherapy

Innate effector cells are immune cells endowed with host protective features and cytotoxic functions. By sensing the tissue environment, innate cells have an important role in regulating the transition from homeostasis to inflammation and the establishment of pathological states, including the onset and development of cancer. The tumor microenvironment induces molecular and functional modifications in innate cells, dampening their capability to initiate and sustain anti-tumor immune responses. Emerging studies clearly showed a contribution of the microbiota in modulating the functions of innate cells in cancer. Commensal microorganisms can not only directly interact with innate cells in the tumor microenvironment but can also exert immunomodulatory features from non-tumor sites through the release of microbial products. The microbiota can mediate the priming of innate cells at mucosal tissues and determine the strength of immune responses mediated by such cells when they migrate to non-mucosal tissues, having an impact on cancer. Finally, several evidences reported a strong contribution of the microbiota in promoting innate immune responses during anti-cancer therapies leading to enhanced therapeutic efficacy. In this review, we considered the current knowledge on the role of the microbiota in shaping host innate immune responses in cancer.

Dynamics of oral human papillomavirus infection in healthy population and head and neck cancer

The recent increase in high-risk human papillomavirus (HR-HPV)-associated oral and oropharyngeal cancers has gained considerable importance due to their distinct clinical and molecular characteristics. However, the natural history of oral HPV from acquisition to persistence and malignant transformation is still unclear. The global prevalence of oral HPV infection in healthy individuals ranges from 0.67% to 35%, while 31%-38.5% in head and neck cancer (HNC). The persistence rate of oral HR-HPV infection is 5.5% -12.8% globally. India has the highest HNC burden due to apparent differences in predisposing factors compared with the West. The prevalence of oral HPV in healthy individuals and its contribution to HNC is less evident in Indian studies. HR-HPV-associated HNC in this region accounts for 26%, with an active infection in 8%-15% of these tumors. There is a lack of concordance in the expression of p16 as a surrogate marker for HPV detection in HNC because of differences in behavioral risk factors. Due to a lack of evidence, treatment de-escalation cannot be implemented despite the improved outcome of HPV-associated oropharyngeal cancers. This review critically analyzes the existing literature on the dynamics of oral HPV infection and HPV-associated HNC, identifying potential avenues for future research. A better understanding of the oncogenic role of HR-HPV in HNC will help to formulate novel therapeutic approaches and is expected to have a significant public health impact as preventive strategies can be implemented.

High levels of HPV16-L1 antibody but not HPV16 DNA load or integration predict oropharyngeal patient outcome: The Papillophar study

The incidence of oropharyngeal cancers (OPC) is increasing in the world. Among OPC, those induced by human papillomaviruses have a better prognosis than non-HPV-associated OPC. The objective of this study was to highlight the relevance of HPV16 load, HPV16 DNA integration and HPV16-L1 serology on progression-free survival and overall survival of OPC patients. The PAPILLOPHAR cohort consists of 362 patients with oropharyngeal squamous cell carcinomas prospectively followed up for 5 years after treatment. Tumor biopsies and sera were collected at inclusion to investigate tumor HPV DNA/RNA characteristics and HPV16 L1 serology, respectively. Twenty-seven percent of tumor biopsies were HPV DNA- and RNA-positive and HPV16 represented 93% of HPV-positive cases. Among them, neither HPV16 viral load nor HPV16 DNA integration was associated with overall survival (OS) or progression-free survival (PFS). In contrast, high anti-HPV16 L1 antibody titers were significantly associated with a better OS and PFS. This study reveals that HPV16 load and integration are not relevant prognosis biomarkers in OPC patients.Clinical Relevance: High levels of HPV16 L1 antibodies may be useful to predict OPC patient outcome following treatment.ClinicalTrials.gov Identifier: NCT00918710, May 2017.

Adaptive immune response in pathogenesis and treatment of head and neck squamous cell carcinoma: the influence of immunosuppression factors and gender

An obvious trend of the last decade in head and neck squamous cell carcinoma pathogenesis evaluation is awareness of the impact of immune response disorders on disease manifestation. The review presents an analysis of the differences in the type and degree of immunosuppression, as well as treatment response in head and neck squamous cell carcinoma patients in accordance with influencing carcinogenic factor, gender, age of the patient and concomitant diseases. An increase in CD8+ T-lymphocytes and a decrease of memory T-cells has been evaluated in smoking and alcohol abusing patients with head and neck squamous cell carcinoma, and a smaller number of CD8+ T-lymphocytes were detected in the tumor microenvironment compared to non-smoking and non-drinking patients. Studies have shown that the improved prognosis of patients with human papillomavirus (Hpv) – associated head and neck squamous cell carcinoma is largely due to the presence of antibodies against Hpv E6 and E7, E7-specific CD8+T lymphocytes in periphe ral blood and a high level of tumor-infiltrating T lymphocytes. The issue of gender differences in the type of immune response is widely discussed. It has been shown that the use of immune response checkpoint inhibitors is more effective in improving survival rates in men, and the use of these drugs in combination with chemotherapy is more effective in women. In addition, in elderly cancer patients, numerous age-associated T-lymphocyte’s function changes were revealed, including a decrease in the number of naive T-lymphocytes due to age-related involution of the thymus and an in crease in the relative number of memory cells and effector cells. Thus, it is clear that immunosuppression type, as well as treatment response, differ depending on the influencing factor, gender, age of the patient, as well as comorbidities.

Absolute Risk of Oropharyngeal Cancer After an HPV16-E6 Serology Test and Potential Implications for Screening: Results From the Human Papillomavirus Cancer Cohort Consortium

PURPOSE

Seropositivity for the HPV16-E6 oncoprotein is a promising marker for early detection of oropharyngeal cancer (OPC), but the absolute risk of OPC after a positive or negative test is unknown.

METHODS

We constructed an OPC risk prediction model that integrates (1) relative odds of OPC for HPV16-E6 serostatus and cigarette smoking from the human papillomavirus (HPV) Cancer Cohort Consortium (HPVC3), (2) US population risk factor data from the National Health Interview Survey, and (3) US sex-specific population rates of OPC and mortality.

RESULTS

The nine HPVC3 cohorts included 365 participants with OPC with up to 10 years between blood draw and diagnosis and 5,794 controls. The estimated 10-year OPC risk for HPV16-E6 seropositive males at age 50 years was 17.4% (95% CI, 12.4 to 28.6) and at age 60 years was 27.1% (95% CI, 19.2 to 45.4). Corresponding 5-year risk estimates were 7.3% and 14.4%, respectively. For HPV16-E6 seropositive females, 10-year risk estimates were 3.6% (95% CI, 2.5 to 5.9) at age 50 years and 5.5% (95% CI, 3.8 to 9.2) at age 60 years and 5-year risk estimates were 1.5% and 2.7%, respectively. Over 30 years, after a seropositive result at age 50 years, an estimated 49.9% of males and 13.3% of females would develop OPC. By contrast, 10-year risks among HPV16-E6 seronegative people were very low, ranging from 0.01% to 0.25% depending on age, sex, and smoking status.

CONCLUSION

We estimate that a substantial proportion of HPV16-E6 seropositive individuals will develop OPC, with 10-year risks of 17%-27% for males and 4%-6% for females age 50-60 years in the United States. This high level of risk may warrant periodic, minimally invasive surveillance after a positive HPV16-E6 serology test, particularly for males in high-incidence regions. However, an appropriate clinical protocol for surveillance remains to be established.

Detection of circulating tumor human papillomavirus DNA before diagnosis of HPV-positive head and neck cancer

Human papillomavirus (HPV), most commonly HPV16, causes a growing subset of head and neck squamous cell carcinomas (HNSCCs), including the overwhelming majority of oropharynx squamous cell carcinomas in many developed countries. Circulating biomarkers for HPV-positive HNSCC may allow for earlier diagnosis, with potential to decrease morbidity and mortality. This case-control study evaluated whether circulating tumor HPV DNA (ctHPVDNA) is detectable in prediagnostic plasma from individuals later diagnosed with HPV-positive HNSCC. Cases were participants in a hospital-based research biobank with archived plasma collected ≥6 months before HNSCC diagnosis, and available archival tumor tissue for HPV testing. Controls were biobank participants without cancer or HPV-related diagnoses, matched 10:1 to cases by sex, race, age and year of plasma collection. HPV DNA was detected in plasma and tumor tissue using a previously validated digital droplet PCR-based assay that quantifies tumor-tissue-modified viral (TTMV) HPV DNA. Twelve HNSCC patients with median age of 68.5 years (range, 51-87 years) were included. Ten (83.3%) had HPV16 DNA-positive tumors. ctHPV16DNA was detected in prediagnostic plasma from 3 of 10 (30%) patients with HPV16-positive tumors, including 3 of 7 (43%) patients with HPV16-positive oropharynx tumors. The timing of the plasma collection was 19, 34 and 43 months before cancer diagnosis. None of the 100 matched controls had detectable ctHPV16DNA. This is the first report that ctHPV16 DNA is detectable at least several years before diagnosis of HPV16-positive HNSCC for a subset of patients. Further investigation of ctHPV16DNA as a biomarker for early diagnosis of HPV16-positive HNSCC is warranted.

Imaging of human papilloma virus associated oropharyngeal squamous cell carcinoma and its impact on diagnosis, prognostication, and response assessment

The clinical behaviour and outcomes of patients with oropharyngeal cancer (OPC) may be dichotomised according to their association with human papilloma virus (HPV) infection. Patients with HPV-associated disease (HPV+OPC) have a distinct demographic profile, clinical phenotype and demonstrate considerably better responses to chemoradiotherapy. This has led to a reappraisal of staging and treatment strategies for HPV+OPC, which are underpinned by radiological data. Structural modalities, such as CT and MRI can provide accurate staging information. These can be combined with ultrasound-guided tissue sampling and functional techniques (such as diffusion-weighted MRI and 18F-fludeoxyglucose positron emission tomography-CT) to monitor response to treatment, derive prognostic information, and to identify individuals who might benefit from intensification or deintensification strategies. Furthermore, advanced MRI techniques, such as intravoxel incoherent motion and perfusion MRI as well as application of artificial intelligence and radiomic techniques, have shown promise in treatment response monitoring and prognostication. The following review will consider the contemporary role and knowledge on imaging in HPV+OPC.

Genetic variation within the human papillomavirus type 16 genome is associated with oropharyngeal cancer prognosis

PURPOSE

A significant barrier to adoption of de-escalated treatment protocols for human papillomavirus-driven oropharyngeal cancer (HPV-OPC) is that few predictors of poor prognosis exist. We conducted the first large whole-genome sequencing (WGS) study to characterize the genetic variation of the HPV type 16 (HPV16) genome and to evaluate its association with HPV-OPC patient survival.

PATIENTS AND METHODS

A total of 460 OPC tumor specimens from two large United States medical centers (1980-2017) underwent HPV16 whole-genome sequencing. Site-specific variable positions [single nucleotide polymorphisms (SNPs)] across the HPV16 genome were identified. Cox proportional hazards model estimated hazard ratios (HRs) and 95% confidence intervals (CIs) for overall survival by HPV16 SNPs. Harrell C-index and time-dependent positive predictive value (PPV) curves and areas under the PPV curves were used to evaluate the predictive accuracy of HPV16 SNPs for overall survival.

RESULTS

A total of 384 OPC tumor specimens (83.48%) passed quality control filters with sufficient depth and coverage of HPV16 genome sequencing to be analyzed. Some 284 HPV16 SNPs with a minor allele frequency ≥1% were identified. Eight HPV16 SNPs were significantly associated with worse survival after false discovery rate correction (individual prevalence: 1.0%-5.5%; combined prevalence: 15.10%); E1 gene position 1053 [HR for overall survival (HRos): 3.75, 95% CI 1.77-7.95; Pfdr = 0.0099]; L2 gene positions 4410 (HRos: 5.32, 95% CI 1.91-14.81; Pfdr = 0.0120), 4539 (HRos: 6.54, 95% CI 2.03-21.08; Pfdr = 0.0117); 5050 (HRos: 6.53, 95% CI 2.34-18.24; Pfdr = 0.0030), and 5254 (HRos: 7.76, 95% CI 2.41-24.98; Pfdr = 0.0030); and L1 gene positions 5962 (HRos: 4.40, 95% CI 1.88-10.31; Pfdr = 0.0110) and 6025 (HRos: 5.71, 95% CI 2.43-13.41; Pfdr = 0.0008) and position 7173 within the upstream regulatory region (HRos: 9.90, 95% CI 3.05-32.12; Pfdr = 0.0007). Median survival time for patients with ≥1 high-risk HPV16 SNPs was 3.96 years compared with 18.67 years for patients without a high-risk SNP; log-rank test P < 0.001. HPV16 SNPs significantly improved the predictive accuracy for overall survival above traditional factors (age, smoking, stage, treatment); increase in C-index was 0.069 (95% CI 0.019-0.119, P < 0.001); increase in area under the PPV curve for predicting 5-year survival was 0.068 (95% CI 0.015-0.111, P = 0.008).

CONCLUSIONS

HPV16 genetic variation is associated with HPV-OPC prognosis and can improve prognostic accuracy.

Fabricated Metal-Organic Frameworks (MOFs) as luminescent and electrochemical biosensors for cancer biomarkers detection

In the health domain, a major challenge is the detection of diseases using rapid and cost-effective techniques. Most of the existing cancer detection methods show poor sensitivity and selectivity and are time consuming with high cost. To overcome this challenge, we analyzed porous fabricated metal-organic frameworks (MOFs) that have better structures and porosities for enhanced biomarker sensing. Here, we summarize the use of fabricated MOF luminescence and electrochemical sensors in devices for cancer biomarker detection. Various strategies of fabrication and the role of fabricated materials in sensing cancer biomarkers have been studied and described. The structural properties, sensing mechanisms, roles of noncovalent interactions, limits of detection, modeling, advantages, and limitations of MOF sensors have been well-discussed. The study presents an innovative technique to detect the cancer biomarkers by the use of luminescence and electrochemical MOF sensors. In addition, the potential association studies have been opening the way for personalized patient treatments and the development of new cancer-detecting devices.

The tumor immune microenvironments of HPV+ and HPV- head and neck cancers

Human papillomaviruses (HPVs) are the etiological agent of a significant, and increasing, fraction of head and neck squamous cell carcinomas (HNSCC)-a heterogenous group of malignancies in the head and neck region. HPV infection accounts for approximately 25% of all cases, with the remainder typically caused by smoking and excessive alcohol consumption. These distinct etiologies lead to profound clinical and immunological differences between HPV-positive (HPV⁺ ) and HPV-negative (HPV^- ) HNSCC, likely related to the expression of exogenous viral antigens in the HPV⁺ subtype. Specifically, HPV⁺ HNSCC patients generally exhibit better treatment response compared to those with HPV^- disease, leading to a more favorable prognosis, with lower recurrence rate, and longer overall survival time. Importantly, a plethora of studies have illustrated that the tumor immune microenvironment (TIME) of HPV⁺ HNSCC has a strikingly distinct immune composition to that of its HPV^- counterpart. The HPV⁺ TIME is characterized as being immunologically "hot," with more immune infiltration, higher levels of T-cell activation, and higher levels of immunoregulation compared to the more immunologically "cold" HPV^- TIME. In general, cancers with an immune "hot" TIME exhibit better treatment response and superior clinical outcomes in comparison to their immune "cold" counterparts. Indeed, this phenomenon has also been observed in HPV⁺ HNSCC patients, highlighting the critical role of the TIME in influencing prognosis, and further validating the use of cancer therapies that capitalize on the mobilization and/or modulation of the TIME. This article is categorized under: Cancer > Molecular and Cellular Physiology Infectious Diseases > Molecular and Cellular Physiology.

Epigenetic biomarkers of ageing are predictive of mortality risk in a longitudinal clinical cohort of individuals diagnosed with oropharyngeal cancer

BACKGROUND

Epigenetic clocks are biomarkers of ageing derived from DNA methylation levels at a subset of CpG sites. The difference between age predicted by these clocks and chronological age, termed "epigenetic age acceleration", has been shown to predict age-related disease and mortality. We aimed to assess the prognostic value of epigenetic age acceleration and a DNA methylation-based mortality risk score with all-cause mortality in a prospective clinical cohort of individuals with head and neck cancer: Head and Neck 5000. We investigated two markers of intrinsic epigenetic age acceleration (IEAAHorvath and IEAAHannum), one marker of extrinsic epigenetic age acceleration (EEAA), one optimised to predict physiological dysregulation (AgeAccelPheno), one optimised to predict lifespan (AgeAccelGrim) and a DNA methylation-based predictor of mortality (ZhangScore). Cox regression models were first used to estimate adjusted hazard ratios (HR) and 95% confidence intervals (CI) for associations of epigenetic age acceleration with all-cause mortality in people with oropharyngeal cancer (n = 408; 105 deaths). The added prognostic value of epigenetic markers compared to a clinical model including age, sex, TNM stage and HPV status was then evaluated.

RESULTS

IEAAHannum and AgeAccelGrim were associated with mortality risk after adjustment for clinical and lifestyle factors (HRs per standard deviation [SD] increase in age acceleration = 1.30 [95% CI 1.07, 1.57; p = 0.007] and 1.40 [95% CI 1.06, 1.83; p = 0.016], respectively). There was weak evidence that the addition of AgeAccelGrim to the clinical model improved 3-year mortality prediction (area under the receiver operating characteristic curve: 0.80 vs. 0.77; p value for difference = 0.069).

CONCLUSION

In the setting of a large, clinical cohort of individuals with head and neck cancer, our study demonstrates the potential of epigenetic markers of ageing to enhance survival prediction in people with oropharyngeal cancer, beyond established prognostic factors. Our findings have potential uses in both clinical and non-clinical contexts: to aid treatment planning and improve patient stratification.

Performance of oral HPV DNA, oral HPV mRNA and circulating tumor HPV DNA in the detection of HPV-related oropharyngeal cancer and cancer of unknown primary

A biomarker that is useful for the detection of human papillomavirus (HPV)‐related oropharyngeal cancer (OPC) and cancer of unknown primary (CUP) is indispensable. We evaluated the diagnostic performance of HPV DNA and mRNA in oral gargle samples and circulating tumor HPV16 DNA (ctHPV16DNA) in blood samples. Oral HPV DNA and mRNA were analyzed using commercially available HPV assays of the GENOSEARCH HPV31 and Aptima, respectively. ctHPV16DNA was analyzed using in‐house droplet digital polymerase chain reaction. Seventy‐four patients with OPC and eight patients with CUP were included. The sensitivity and specificity of oral HPV DNA, oral HPV mRNA, and ctHPV16DNA were 82% (95% confidence interval [CI] = 66‐92) and 100% (95% CI = 88‐100), 85% (95% CI = 69‐94) and 94% (95% CI = 73‐100), and 93% (95% CI = 81‐99) and 97% (95% CI = 84‐100), respectively, for HPV16‐related OPC, while those were 20% (95% CI = 1‐72) and 100% (95% CI = 3‐100), 0% (95% CI = 0‐52) and 100% (95% CI = 3‐100), and 100% (95% CI = 54‐100) and 100% (95% CI = 16‐100), respectively, for HPV16‐related CUP. The sensitivity of ctHPV16DNA for HPV16‐related OPC was higher than that of oral biomarkers, though the difference was not statistically significant. ctHPV16DNA remarkably correlated with the anatomic extent of disease, total metabolic tumor volume and HPV16 copy number per tumor genome in patients with HPV16‐related OPC/CUP, whereas oral biomarkers did not. In conclusion, ctHPV16DNA is a potentially promising biomarker for HPV16‐related OPC, while further studies are required for HPV16‐related CUP.

What's new?

A minimally‐invasive biomarker that allows the detection of human papillomavirus (HPV)‐related oropharyngeal cancer and cancer of unknown primary is indispensable. Here, the authors show that circulating tumour HPV DNA (ctHPVDNA) correlates with the tumour burden and HPV copy number per tumour genome in HPV‐related oropharyngeal cancer and cancer of unknown primary. Neither oral HPV DNA nor mRNA exhibits such a correlation. ctHPVDNA outperforms oral HPV DNA and mRNA in detecting HPV‐related oropharyngeal cancer and in distinguishing HPV‐related cancer of unknown primary from HPV‐unrelated cancers. ctHPVDNA emerges as a potentially useful biomarker for HPV‐related oropharyngeal cancer and cancer of unknown primary.

Current Status of Human Papillomavirus-Related Head and Neck Cancer: From Viral Genome to Patient Care

Human papillomavirus (HPV) infection identified as a definitive human carcinogen is increasingly being recognized for its role in carcinogenesis of human cancers. Up to 38%-80% of head and neck squamous cell carcinoma (HNSCC) in oropharyngeal location (OPSCC) and nearly all cervical cancers contain the HPV genome which is implicated in causing cancer through its oncoproteins E6 and E7. Given by the biologically distinct HPV-related OPSCC and a more favorable prognosis compared to HPV-negative tumors, clinical trials on de-escalation treatment strategies for these patients have been studied. It is therefore raised the questions for the patient stratification if treatment de-escalation is feasible. Moreover, understanding the crosstalk of HPV-mediated malignancy and immunity with clinical insights from the proportional response rate to immune checkpoint blockade treatments in patients with HNSCC is of importance to substantially improve the treatment efficacy. This review discusses the biology of HPV-related HNSCC as well as successful clinically findings with promising candidates in the pipeline for future directions. With the advent of various sequencing technologies, further biomolecules associated with HPV-related HNSCC progression are currently being identified to be used as potential biomarkers or targets for clinical decisions throughout the continuum of cancer care.

Defining HPV-specific B cell responses in patients with head and neck cancer

Tumours often contain B cells and plasma cells but the antigen specificity of these intratumoral B cells is not well understood^1-8. Here we show that human papillomavirus (HPV)-specific B cell responses are detectable in samples from patients with HPV-positive head and neck cancers, with active production of HPV-specific IgG antibodies in situ. HPV-specific antibody secreting cells (ASCs) were present in the tumour microenvironment, with minimal bystander recruitment of influenza-specific cells, suggesting a localized and antigen-specific ASC response. HPV-specific ASC responses correlated with titres of plasma IgG and were directed against the HPV proteins E2, E6 and E7, with the most dominant response against E2. Using intratumoral B cells and plasma cells, we generated several HPV-specific human monoclonal antibodies, which exhibited a high degree of somatic hypermutation, consistent with chronic antigen exposure. Single-cell RNA sequencing analyses detected activated B cells, germinal centre B cells and ASCs within the tumour microenvironment. Compared with the tumour parenchyma, B cells and ASCs were preferentially localized in the tumour stroma, with well-formed clusters of activated B cells indicating ongoing germinal centre reactions. Overall, we show that antigen-specific activated and germinal centre B cells as well as plasma cells can be found in the tumour microenvironment. Our findings provide a better understanding of humoral immune responses in human cancer and suggest that tumour-infiltrating B cells could be harnessed for the development of therapeutic agents.

Diagnostic Accuracy of HPV Detection in Patients with Oropharyngeal Squamous Cell Carcinomas: A Systematic Review and Meta-Analysis

The aim of the study was to evaluate the diagnostic accuracy of Human Papillomavirus (HPV) techniques in oropharyngeal cancer. PubMed, EMBASE, the Cochrane Library and clinicaltrials.org were systematically searched for studies reporting methods of HPV detection. Primary outcomes were sensitivity and specificity of HPV detection. In this case, 27 studies were included (n = 5488, 41.6% HPV+). In this case, 13 studies evaluated HPV detection in tumour tissue, nine studies examined HPV detection in blood samples and five studies evaluated HPV detection in oral samples. Accuracy of HPV detection in tumour tissue was high for all detection methods, with pooled sensitivity ranging from 81.1% (95% CI 71.9-87.8) to 93.1% (95% CI 87.4-96.4) and specificity ranging from 81.1% (95% CI 71.9-87.8) to 94.9% (95% CI 79.1-98.9) depending on detection methods. Overall accuracy of HPV detection in blood samples revealed a sensitivity of 81.4% (95% CI 62.9-91.9) and a specificity of 94.8% (95% CI 91.4-96.9). In oral samples pooled sensitivity and specificity were lower (77.0% (95% CI 68.8-83.6) and 74.0% (95% CI 58.0-85.4)). In conclusion, we found an overall high accuracy for HPV detection in tumour tissue regardless of the HPV detection method used. HPV detection in blood samples may provide a promising new way of HPV detection.

Cancer of the Oropharynx and the Association with Human Papillomavirus

Squamous cell carcinoma of the oropharynx (OPC) consists of human papillomavirus (HPV)-negative disease caused by tobacco and alcohol use, and HPV-positive disease caused by the sexually transmitted infection HPV. These entities have unique but overlapping risk factors, epidemiologic trends, staging systems, and survival outcomes. HPV-positive tumor status confers a significant survival benefit compared with HPV-negative disease. OPC treatment entails a combination of surgery, radiation, and chemotherapy. Ongoing trials will determine whether treatment of HPV-related disease may be safely deintensified to decrease morbidity. Emerging HPV-related biomarkers are under study as tools to inform screening, diagnosis, treatment, and surveillance for HPV-positive OPC.

Serum HPV16 E7 Oncoprotein Is a Recurrence Marker of Oropharyngeal Squamous Cell Carcinomas

Despite improved prognosis for many HPV-positive head and neck squamous cell carcinomas (HNSCCs), some cases are still marked by recurrence and metastasis. Our study aimed to identify novel biomarkers for patient stratification. Classical HPV markers: HPV-DNA, p16 and HPV mRNA expression were studied in HNSCC (n = 67) and controls (n = 58) by qPCR. Subsequently, ELISA tests were used for HPV16 L1 antibody and HPV16 E7 oncoprotein detection in serum at diagnosis and follow-up. All markers were correlated to relapse-free survival (RFS) and overall survival (OS). HPV-DNA was found in HNSCCs (29.85%), HPV16-DNA in 95% of cases, HPV16 E7 mRNA was revealed in 93.75%. p16 was overexpressed in 75% of HPV-positive HNSCC compared to negative samples and controls (p < 0.001). Classical markers correlated with improved OS (p < 0.05). Serological studies showed similar proportions of HPV16 L1 antibodies in all HNSCCs (p > 0.05). Serum E7 oncoprotein was present in 30% HPV-positive patients at diagnosis (p > 0.05) and correlated to HNSCC HPV16 E7 mRNA (p < 0.01), whereas it was associated to worse RFS and OS, especially for oropharyngeal squamous cell carcinoma (OPSCC) (p < 0.01). Detection of circulating HPV16 E7 oncoprotein at diagnosis may be useful for stratifying and monitoring HPV-positive HNSCC patients for worse prognosis, providing clinicians a tool for selecting patients for treatment de-escalation.

Current Status of Human Papillomavirus-Related Head and Neck Cancer: From Viral Genome to Patient Care

Human papillomavirus (HPV) infection identified as a definitive human carcinogen is increasingly being recognized for its role in carcinogenesis of human cancers. Up to 38%–80% of head and neck squamous cell carcinoma (HNSCC) in oropharyngeal location (OPSCC) and nearly all cervical cancers contain the HPV genome which is implicated in causing cancer through its oncoproteins E6 and E7. Given by the biologically distinct HPV-related OPSCC and a more favorable prognosis compared to HPV-negative tumors, clinical trials on de-escalation treatment strategies for these patients have been studied. It is therefore raised the questions for the patient stratification if treatment de-escalation is feasible. Moreover, understanding the crosstalk of HPV-mediated malignancy and immunity with clinical insights from the proportional response rate to immune checkpoint blockade treatments in patients with HNSCC is of importance to substantially improve the treatment efficacy. This review discusses the biology of HPV-related HNSCC as well as successful clinically findings with promising candidates in the pipeline for future directions. With the advent of various sequencing technologies, further biomolecules associated with HPV-related HNSCC progression are currently being identified to be used as potential biomarkers or targets for clinical decisions throughout the continuum of cancer care.

Relevance of Human Papillomaviruses in Head and Neck Cancer-What Remains in 2021 from a Clinician's Point of View?

Human papillomaviruses (HPV) cause a subset of head and neck cancers (HNSCC). HPV16 predominantly signs responsible for approximately 10% of all HNSCC and over 50% of tonsillar (T)SCCs. Prevalence rates depend on several factors, such as the geographical region where patients live, possibly due to different social and sexual habits. Smoking plays an important role, with non-smoking patients being mostly HPV-positive and smokers being mostly HPV-negative. This is of unparalleled clinical relevance, as the outcome of (non-smoking) HPV-positive patients is significantly better, albeit with standard and not with de-escalated therapies. The results of the first prospective de-escalation studies have dampened hopes that similar superior survival can be achieved with de-escalated therapy. In this context, it is important to note that the inclusion of p16^INK4A (a surrogate marker for HPV-positivity) in the 8th TMN-classification has only prognostic, not therapeutic, intent. To avoid misclassification, highest precision in determining HPV-status is of utmost importance. Whenever possible, PCR-based methods, still referred to as the "gold standard”, should be used. New diagnostic antibodies represent some hope, e.g., to detect primaries and recurrences early. Prophylactic HPV vaccination should lead to a decline in HPV-driven HNSCC as well. This review discusses the above aspects in detail.

Sensitivity and Specificity of Human Papillomavirus (HPV) 16 Early Antigen Serology for HPV-Driven Oropharyngeal Cancer: A Systematic Literature Review and Meta-Analysis

Simple Summary

Serum antibodies against human papillomavirus 16 (HPV16) proteins are associated with HPV-driven oropharyngeal cancer (HPV-OPC). The HPV status of OPC cases is clinically relevant because patients with HPV-OPC show improved survival and treatment response compared to tobacco- or alcohol-induced OPC. In clinical settings, molecular HPV tumor status is usually determined by tissue-based methods detecting molecular markers, such as viral nucleic acids or p16 overexpression. Antibodies against HPV16 in peripheral blood were shown to be very accurate in determining the molecular HPV tumor status in multiple studies. In this work, we reviewed and summarized the available literature on the performance of HPV16 serology for E2, E6 and E7 antibodies to determine molecular HPV tumor status in OPC cases in comparison with tissue-based reference methods. We calculated summary estimates across different studies for sensitivity and specificity, and we investigated factors influencing test performance.

Abstract

Antibodies against HPV16 early proteins have been shown to be promising biomarkers for the identification of HPV-driven oropharyngeal cancer (HPV-OPC) among OPC cases in multiple studies. A systematic literature search was performed to identify original research articles comparing HPV early antigen serology with established reference methods to determine molecular HPV tumor status. Random-effects models were used to calculate summary estimates for sensitivity and specificity of HPV16 E2, E6 and E7 serology for HPV-OPC. Subgroup analyses were performed to explore heterogeneity across studies and describe variables associated with test performance. We identified n = 23 studies meeting all eligibility criteria and included these in the meta-analysis. E6 serology showed the best performance with pooled sensitivity and specificity estimates of 83.1% (95% confidence interval (CI) 72.5–90.2%) and 94.6% (95% CI 89.0–97.4%), respectively, while E2 and E7 serological assays were highly specific (E2: 92.5% (95% CI 79.1–97.6%); E7: 88.5% (95% CI 77.9–94.4%)) but moderately sensitive (E2: 67.8% (95% CI 58.9–75.6%); E7: 67.0% (95% CI 63.2–70.6%)). Subgroup analyses revealed increased pooled sensitivity for bacterially (89.9% (95% CI 84.5–93.6%)) vs. in vitro expressed E6 antigen (55.3% (95% CI 41.0–68.7%)), while both showed high specificity (95.2% (95% CI 93.0–96.7%) and 91.1% (95% CI 46.6–99.2%), respectively). Pooled specificity estimates for HPV16 E2, E6 and E7 serology were significantly lower in studies utilizing HPV DNA PCR as the only molecular reference method compared to those using a combination of any two reference methods (HPV DNA, RNA, in situ hybridization (ISH), p16 immunohistochemistry (IHC)), or histopathological reference methods (ISH or p16 IHC) as stand-alone marker. In conclusion, HPV16 E6 seropositivity is a highly sensitive and specific biomarker for HPV-OPC. However, its performance differs between serological assays and depends on molecular reference methods.

Virus-Associated Biomarkers in Oropharyngeal and Nasopharyngeal Cancers and Recurrent Respiratory Papillomatosis

Nasopharyngeal cancer (NPC) is known to be associated with Epstein–Barr virus (EBV). Pre-treatment and post-treatment detection of plasma cell-free EBV DNA has been shown to be useful as a diagnostic as well as a prognostic factor in NPC. On the other hand, the incidence of human papillomavirus (HPV)-associated oropharyngeal cancer (OPC) is increasing. In contrast to cervical cancer, which is classically known to be an HPV-associated malignancy, HPV testing is not clinically applied for OPC, except for p16 immunostaining as a surrogate marker of HPV infection. One of the major characteristics of HPV-associated OPC is its association with a good prognosis compared with non-HPV-associated OPC. However, some patients still have a poor prognosis. Another characteristic of HPV-associated OPC is the distinct risk factor of high sexual activity. Establishing a biomarker for the prediction of the prognosis before and/or after initial treatment, as well as for diagnosis in populations at high risk, is of marked interest. With this background, HPV DNA detection in plasma and oral rinses has become an area of focus. In this review, the current significance of HPV DNA detection in plasma and oral rinse samples, as well as serum HPV antibody levels, is evaluated.

Investigating the association between serum human papillomavirus type 16 E7 antibodies and risk of head and neck cancer

Human papillomavirus (HPV) is recognized as a major cause of oropharyngeal cancer (OPC) in Western countries. Less is known regarding its contribution to the OPC occurring in Asia. The current study aimed to investigate the association between antibody responses to HPV16 E7 and head and neck cancer (HNC) risk in a hospital‐based case–control study conducted in Taiwan with 693 HNC cases and 1,035 controls. A positive association was observed between seropositivity to HPV16 E7 and OPC risk, whereas no significant association was found in the non‐OPC cases. The increased OPC risk associated with seropositivity to HPV16 E7 was more significant among nonbetel quid or noncigarette users. Seropositivity to HPV16 E7 showed moderate agreement with P16 expression in OPC. OPC patients that were seropositive to HPV16 E7 or p16 positive were more highly educated and less likely to use alcohol, betel quids, and cigarettes compared to HPV16 E7 seronegative or p16 negative OPC patients. Furthermore, patients with p16 positive OPC were more likely to be women compared to patients with p16 negative OPC, likely owing to the low prevalence of alcohol, betel quid, and cigarette users among women. Overall, this study suggested that similar to Western countries, HPV may also be an important risk factor of OPC in Taiwan. With the declining consumption of betel quids and cigarettes in Taiwan, a higher percentage of OPC cases in Taiwan will be attributed to HPV in the future. Public health measures, including HPV vaccination, need to be implemented to prevent the occurrence of HPV‐positive OPC.

The current study found a a positive association between seropositivity to HPV16 E7 and oropharyngeal cancer risk. This study suggested that similar to Western countries, HPV may also be an important risk factor of OPC in Taiwan.

Circulating HPV DNA in the Management of Oropharyngeal and Cervical Cancers: Current Knowledge and Future Perspectives

Human papillomaviruses (HPVs) are associated with invasive malignancies, including almost 100% of cervical cancers (CECs), and 35–70% of oropharyngeal cancers (OPCs). HPV infection leads to clinical implications in related tumors by determining better prognosis and predicting treatment response, especially in OPC. Currently, specific and minimally invasive tests allow for detecting HPV-related cancer at an early phase, informing more appropriately therapeutical decisions, and allowing for timely disease monitoring. A blood-based biomarker detectable in liquid biopsy represents an ideal candidate, and the use of circulating HPV DNA (ct-DNA) itself could offer the highest specificity for such a scope. Circulating HPV DNA is detectable in the greatest part of patients affected by HPV-related cancers, and studies have demonstrated its potential usefulness for CEC and OPC clinical management. Unfortunately, when using conventional polymerase chain reaction (PCR), the detection rate of serum HPV DNA is low. Innovative techniques such as droplet-based digital PCR and next generation sequencing are becoming increasingly available for the purpose of boosting HPV ct-DNA detection rate. We herein review and critically discuss the most recent and representative literature, concerning the role of HPV ctDNA in OPC and CEC in the light of new technologies that could improve the potential of this biomarker in fulfilling many of the unmet needs in the clinical management of OPC and CEC patients.

Survival advantage in patients with human papillomavirus-driven oropharyngeal cancer and variation by demographic characteristics and serologic response: Findings from Head and Neck 5000

BACKGROUND

Patients with human papillomavirus (HPV)-driven oropharyngeal cancer (OPC) experience better survival than those with HPV-negative OPC. It is unclear whether this benefit varies by demographic characteristics and serologic response.

METHODS

Records from 1411 patients with OPC who had HPV serology data were analyzed. HPV status was based on HPV type 16 (HPV16) E6 serology. Participants were followed for a median of 5.9 years, and Cox proportional hazards models were used to estimate hazard ratios (HRs). The association between HPV status and overall survival was analyzed by age group, sex, smoking status, tumor site, HPV antibody levels, and HPV antibody pattern. Models were adjusted for age, sex, smoking status, and comorbidity.

RESULTS

For the overall association between HPV status and survival, the fully adjusted HR was 0.43 (95% CI, 0.33-0.56). The HR was 0.19 (95% CI, 0.10-0.35) for participants aged ≤54 years, 0.38 (95% CI, 0.25-0.56) for those aged 55 to 64 years, and 0.73 (95% CI, 0.47-1.13) for those aged ≥65 years (P for interaction = .023). There was no clear evidence for an interaction by sex, smoking status, or tumor site. Survival did not differ according to E6 antibody levels in those who were seropositive. All seropositivity patterns were associated with increased survival compared with a pattern of seronegativity for all antibodies. Patients who are positive for E1, E2, E6, and E7 may experience better survival.

CONCLUSIONS

HPV status confers a survival advantage across all groups. This survival advantage is more marked for younger patients. The HPV antibody pattern, but not the antibody level, may also affect survival.

Elimination of HPV-associated oropharyngeal cancers in Nordic countries

Incidence of human papillomavirus (HPV, most notably HPV type 16) associated oropharyngeal squamous cell carcinoma (OPSCC) among middle-aged (50-69 year-old) males has tripled in four high income Nordic countries (Denmark, Finland, Norway and Sweden) over the last 30 years. In Finland and Sweden, this increase was preceded by an HPV16 epidemic in fertile-aged populations in the 1980's. The recent implementation of school-based prophylactic HPV vaccination in early adolescent boys and girls will gradually decrease the incidence, and eventually eliminate the HPV-associated OPSCCs (especially tonsillar and base of tongue carcinomas) in the Nordic countries. However, beyond the adolescent and young adult birth cohorts vaccinated, there are approximately 50 birth cohorts (born in 1995 or before) that would benefit from screening for HPV-associated OPSCC. This article reviews the need, prerequisites, proof-of-concept trial and prospects of preventing HPV-associated OPSCC in the Nordic countries.

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.

Characterization of human papillomavirus (HPV) 16 E6 seropositive individuals without HPV-associated malignancies after 10 years of follow-up in the UK Biobank

BACKGROUND

Antibodies against the HPV16 oncoprotein E6 are promising biomarkers for HPV16-driven oropharyngeal cancer (HPV16-OPC) due to their high sensitivity and specificity, and prospective manifestation. In previous studies, 0•7% of controls without HPV-associated malignancies were HPV16 E6 seropositive of which only a minority is expected to develop HPV16-driven cancer. We aimed to characterise HPV16 E6 antibodies in individuals without HPV-associated malignancies.

METHODS

We analysed serum antibodies against HPV16 E6, E7, L1 and HPV18 L1 in a random sample (n = 9,695) of the prospective UK Biobank cohort (UKB). Excluding individuals with potentially HPV-associated malignancies (n = 192), we assessed risk factors for seropositivity by logistic regression.

FINDINGS

In individuals without potentially HPV-associated malignancies (n = 9,503), the HPV16 E6 seroprevalence was 0•8%. Seropositivity against HPV16 E6 and all other HPV antigens was strongly associated with sexual behaviour. The seroprevalence of HPV16 E6, L1 and HPV18 L1 increased with the number of lifetime sex partners (ptrend<0•005), and all HPV antibodies were associated with same-sex intercourse (ORE6 3•1, 95%CI 1•4-6•9; reference category: no same-sex intercourse). HPV16 E6 and L1 seropositivity were associated with young age (≤17 years) at sexual debut (ORE6 2•0, 95%CI 1•1-3•7) compared with individuals reporting sexual debut at age ≥20 years.

INTERPRETATION

This is the first study characterising HPV16 E6 antibodies in the general UK population. Their strong association with sexual behaviour, and overlapping risk factor profiles with other HPV antibodies support their relevance for HPV16-OPC disease prediction. However, additional risk stratification will be required to identify individuals at highest risk to develop HPV16-OPC.

High-Risk Human Papillomavirus-Related Oropharyngeal Squamous Cell Carcinoma Among Non-Indigenous and Indigenous Populations: A Systematic Review

OBJECTIVE

To estimate the prevalence of oral high-risk human papillomavirus (hr-HPV) infection and the proportion of hr-HPV-related oropharyngeal squamous cell carcinoma (OPSCC) among Indigenous and non-Indigenous populations.

DATA SOURCE

Electronic database searches of PubMed, PubMed Central, Embase, MEDLINE, Scope, and Google Scholar were conducted for articles published from January 2000 until November 2019.

REVIEW METHODS

Studies were included with a minimum of 100 cases assessing hr-HPV infection in either population samples or oropharyngeal cancer tumor series. The objective was to conduct meta-analyses to calculate the pooled prevalence of oral hr-HPV infection by adjusting for age group or sex in primary studies, the incidence of OPSCC, and the proportion of hr-HPV-related OPSCC in Indigenous people and non-Indigenous/general populations.

RESULTS

We identified 47 eligible studies from 157 articles for meta-analyses. The pooled prevalence of oral hr-HPV infection was 7.494% (95% CI, 5.699%-9.289%) in a general population, with a higher prevalence among men (10.651%) than women (5.176%). The pooled incidence rate was 13.395 (95% CI, 9.315-17.475) and 7.206 (95% CI, 4.961-9.450) per 100,000 person-years in Indigenous and non-Indigenous populations, respectively. The overall pooled proportion of hr-HPV-related OPSCC was 50.812% (95 CI, 41.656%-59.969%). The highest proportion was in North America (60.221%), while the lowest proportion was in the Asia-Pacific (34.246%).

CONCLUSION

Our findings suggest that in the general population, the prevalence of oral hr-HPV infection is lower among females and those in younger age groups. The incidence of OPSCC was higher among Indigenous than non-Indigenous populations, with the proportion being highest in North America.

[Tumor biology of oropharyngeal carcinoma]

BACKGROUND

Etiologically, oropharyngeal squamous cell carcinoma (OPSCC) can be divided into OPSCC caused by noxious agents and human papillomavirus (HPV)-driven carcinoma. These types differ with regard to clinical features and prognosis-differences which are rooted in the underlying molecular biology of the tumor.

OBJECTIVE

The aim of this work is to provide an overview of the molecular biological characteristics of the genetics, epigenetics, and immunology of OPSCC.

MATERIALS AND METHODS

A literature review was performed on a selection of genetic, epigenetic, and immunological factors characterizing OPSCC.

RESULTS

The understanding of genetic aberrations and their consequences for cancerogenesis and tumor biology is increasing. Epigenetic phenomena are complementing functional relationships. However, epigenetic mechanisms of gene regulation are complex and much research is still required in this field. Immunological aspects of cancer molecular biology have moved into the focus in light of recent advances in the field of immunotherapy.

CONCLUSION

The tumor biology of OPSCC is primarily defined by its HPV status. Additionally, HPV-independent genetic, epigenetic, and immunological signatures are being defined. From these advances, rationales for new treatment concepts may evolve.

Cell-Free HPV-DNA as a Biomarker for Oropharyngeal Squamous Cell Carcinoma-A Step Towards Personalized Medicine?

Simple Summary

Human papillomavirus (HPV)-related oropharyngeal squamous cell carcinoma (OPSCC) is a distinct tumor entity with relatively favorable overall survival. Nevertheless, up to 25% of HPV-related OPSCC patients develop recurrent or metastatic disease with a fatal outcomes. Biomarkers to enable early diagnosis and to monitor this disease are not established. Liquid biopsy presents a promising minimally invasive method to monitor the cell-free DNA of oncogenic HPV and to enable personalized therapy concepts. Few studies have investigated the role of cell-free HPV DNA (cfHPV-DNA) as a diagnostic marker in patients with OPSCC with variable outcomes. To emphasize the importance of cfHPV-DNA, we performed a literature review and meta-analysis. Our results demonstrate that cfHPV-DNA in patients with OPSCC presents a promising diagnostic tool with high specificity. Nevertheless, further studies with homogeneous inclusion criteria will be necessary to strengthen the role of cfHPV-DNA as a biomarker in the future.

Abstract

Global incidences of oropharyngeal squamous cell carcinoma (OPSCC) are rising due to an association with high-risk human papillomavirus (HPV). Although there is an improved overall survival of HPV-related OPSCC; up to 25% of the patients develop recurrent or distant metastatic disease with a fatal outcomes. Biomarkers to monitor this disease are not established. This meta-analysis reviews the role of cell-free HPV DNA in liquid biopsy (LB) as a biomarker for HPV-related OPSCC. Pubmed, Livivo, and Cochrane Library databases were searched from inception to August, 2020. All studies were analyzed by Meta-DiSc 1.4 and Stata 16.0 statistical software. In total, 16 studies were considered for systematic review, whereas 11 studies met inclusion criteria for meta-analysis, respectively. Pooled sensitivity of cfHPV-DNA at first diagnosis and during follow-up was 0.81 (95% CI; 0.78–0.84) and 0.73 (95% CI; 0.57–0.86), while pooled specificity was 0.98 (95% CI; 0.96–0.99) and 1 (95% CI; 0.99–1). The diagnostic odds ratio (DOR) at first diagnosis was 200.60 (95% CI; 93.31–431.22) and 300.31 (95% CI; 60.94–1479.88) during follow-up. The area under the curve (AUC) of summary receiver operating characteristic (SROC) was 0.99 at first diagnosis and 1.00 during follow-up, respectively. In conclusion, cfHPV-DNA presents a potential biomarker with high specificity in patients with HPV-related OPSCC.

HPV Detection in Head and Neck Squamous Cell Carcinomas: What Is the Issue?

Besides classic tobacco and alcohol risk factors, human papillomavirus (HPV) plays a role in the development of a subset of head and neck squamous cell carcinomas (HNSCCs), and notably oropharynx squamous cell carcinomas (OPSCCs). HPV-induced OPSCCs have a different biological behavior and a better prognosis compared to non-HPV-induced OPSCCs and the eighth-edition TNM classification now separates these two entities. Therefore, determining the HPV status of patients with OPSCC is now essential for treatment, prognosis, and development of clinical trials. In this review, after reminding essential steps of HPV implication in the cell cycle, we describe the existing tools that are currently feasible in routine practice according to facilities available in health structures, with their benefits and drawbacks: HPV PCR, E6/E7 mRNA RT-PCR, E6/E7 mRNA in situ hybridization, HPV DNA in situ hybridization, and P16 immunochemistry. Besides these traditional HPV detection tools, novel diagnostic approaches are being evaluated for HPV-induced OPSCC “ultrastaging.” E6 humoral response and ddPCR-detecting HPVct DNA are two techniques performed on blood and are therefore non-invasive. Baseline E6 humoral levels could have a prognostic value, and HPVct DNA could be helpful for HPV OPSCC recurrence monitoring. At last, next-generation sequencing (NGS)-based “capture HPV” is a technique feasible on biopsies and circulating DNA material. It helps characterize HPV integration status and sites, and it could define prognostic subgroups in HPV-induced OPSCC. These novel precision detection tools could be further integrated in the care of patients with HPV-induced OPSCC.

Immunological Network in Head and Neck Squamous Cell Carcinoma-A Prognostic Tool Beyond HPV Status

Head and neck squamous cell carcinoma (HNSCC) is a highly heterogeneous disease that affects more than 800,000 patients worldwide each year. The variability of HNSCC is associated with differences in the carcinogenesis processes that are caused by two major etiological agents, namely, alcohol/tobacco, and human papillomavirus (HPV). Compared to non-virally induced carcinomas, the oropharyngeal tumors associated with HPV infection show markedly better clinical outcomes and are characterized by an immunologically “hot” landscape with high levels of tumor-infiltrating lymphocytes. However, the standard of care remains the same for both HPV-positive and HPV-negative HNSCC. Surprisingly, treatment de-escalation trials have not shown any clinical benefit in patients with HPV-positive tumors to date, most likely due to insufficient patient stratification. The in-depth analysis of the immune response, which places an emphasis on tumor-infiltrating immune cells, is a widely accepted prognostic tool that might significantly improve both the stratification of HNSCC patients in de-escalation trials and the development of novel immunotherapeutic approaches.

Summary from an international cancer seminar focused on human papillomavirus (HPV)-positive oropharynx cancer, convened by scientists at IARC and NCI

Cancer of the oropharynx has attracted considerable attention in recent years given: (1) an increasing incidence in selected populations over the past three decades; (2) the discovery of human papillomavirus (HPV) infection as the driver of the increase, as opposed to the traditional risk factors such as tobacco (smoking and chewing) and alcohol; and (3) the promise of new prevention and treatment strategies. As a result of such developments, the International Agency for Research on Cancer (IARC) and the US National Cancer Institute (NCI), convened the fourth Cancer Seminar meeting in November 2018 to focus on this topic. This report summarizes the proceedings: a review of recent science on the descriptive epidemiology, etiology, biology, genetics, early detection, pathology and treatment of HPV-positive oropharyngeal cancer, and the formulation of key research questions to be addressed.

Natural and vaccine-induced B cell-derived systemic and mucosal humoral immunity to human papillomavirus

Introduction: Human papillomavirus (HPV) are the causative agent of mucosal neoplasia. Both cervical, anal and oropharyngeal cancers incidence is constantly increasing, making the HPV infection, a significant worldwide concern. Together, the CD8+ T cytotoxic cell-mediated response and the HPV-specific antibody response control most of the HPV infections before the development of cancers.Areas covered: We searched the MEDLINE and EMBASE databases and identified 228 eligible studies from 1987 to 2019 which examines both naturally acquired and vaccine induced humoral immunity against HPV infection in female and male subjects from worldwide origin. Herein, we synthesize current knowledge on the features of systemic and mucosal humoral immunity against HPV. We discuss the issues of the balance between the viral clearance or the escape to the host immune response, the differences between natural and vaccine-induced HPV-specific antibodies and their neutralizing capability. We also discuss the protection afforded after natural infection or following prophylactic vaccination.Expert opinion: Understanding the antibody response induced by HPV infection has led to the design of first-generation prophylactic vaccines. Now, prophylactic vaccination induces protective and long-lasting antibody response which would also strengthened the natural moderate humoral response in people previously exposed to the virus.

Post-treatment human papillomavirus antibody kinetics in cervical cancer patients

Antibodies to the E6 and E7 oncoproteins of high-risk human papillomavirus (HPV) types are strongly associated with HPV-driven cancer, while antibodies against the capsid protein L1 are considered cumulative exposure markers. To test the hypothesis that L1 antibody levels are stable over time, whereas E6 and E7 levels undergo decay after cervical cancer (CxCa) treatment, we performed multiplex serology for HPV16 and 18 antigens E6, E7 and L1 in a post-treatment study of 184 patients with invasive CxCa that were characterized with a median follow-up time of 725 days, and 2-12 sera per patient. Antibody titers significantly decreased within the first six months for HPV16 E6 and E7 but not L1, and stabilized for the following 12 months on a high level, with few patients showing seroreversion. Of 67 patients seropositive for HPV16 E6 at diagnosis, 28 (41.8%) showed a decrease in antibody titers of at least 50% within the first 18 months. Similarly, of 50 HPV16 E7 seropositives, 33 (66.0%) showed decreasing antibody levels, whereas antibody decay was less frequent for HPV16 L1 (12 of 47, 25.5%). Using a power-law mathematical model to characterize antibody decay kinetics, the mean (±s.e.) durations to a 50% reduction in antibody titers within individual patients were estimated to be 56.9 (±26.1) and 56.3 (±19.0) days for HPV16 E6 and E7, respectively. In summary, HPV16 E6 and E7 antibodies undergo a slow but significant decrease in antibody titers within the first 6-18 months following CxCa treatment. However, larger studies are needed to confirm the utility of serology for prediction of disease progression and time to relapse based on antibody decay kinetics. This article is part of the theme issue 'Silent cancer agents: multi-disciplinary modelling of human DNA oncoviruses'.

A Phase 1 Trial Assessing the Safety and Tolerability of a Therapeutic DNA Vaccination Against HPV16 and HPV18 E6/E7 Oncogenes After Chemoradiation for Cervical Cancer

PURPOSE

This study assessed the safety and tolerability of therapeutic immunization against the human papillomavirus (HPV) viral oncoproteins E6 and E7 in patients with cervical cancer after chemoradiation.

METHODS AND MATERIALS

MEDI0457 (INO-3112) is a DNA-based vaccine targeting E6 and E7 of HPV-16/18 that is coinjected with an IL-12 plasmid followed by electroporation with the CELLECTRA 5P device. At 2 to 4 weeks after chemoradiation, patients with newly diagnosed stage IB1-IVA (cohort 1) or persistent/recurrent (cohort 2) cervical cancers were treated with 4 immunizations of MEDI0457 every 4 weeks. The primary endpoints were incidence of adverse events and injection site reactions. Immune responses against HPV antigens were measured by ELISpot for interferon-γ (IFNγ), enzyme-linked immunosorbent assay for antibody responses and multiplexed immunofluorescence for immune cells in cervical biopsy specimens.

RESULTS

Ten patients (cohort 1, n = 7; cohort 2, n = 3) with HPV16 (n = 7) or HPV18 (n = 3) cervical cancers received MEDI0457 after chemoradiation. Treatment-related adverse events were all grade 1, primarily related to the injection site. Eight of 10 patients had detectable cellular or humoral immune responses against HPV antigens after chemoradiation and vaccination: 6 of 10 patients generated anti-HPV antibody responses and 6 of 10 patients generated IFNγ-producing T cell responses. At the completion of chemoradiation and vaccination, cervical biopsy specimens had detectable CD8⁺ T cells and decreased PD-1⁺CD8⁺, PD-L1⁺CD8⁺, and PD-L1⁺CD68⁺ subpopulations. All patients cleared detectable HPV DNA in cervical biopsies by completion of chemoradiation and vaccination.

CONCLUSIONS

Adjuvant MEDI0457 is safe and well tolerated after chemoradiation for locally advanced or recurrent cervical cancers, supporting further investigation into combining tumor-specific vaccines with radiation therapy.

Transcervical sonography and human papillomavirus 16 E6 antibodies are sensitive for the detection of oropharyngeal cancer

BACKGROUND

Human papillomavirus 16 (HPV-16) E6 seropositivity is a promising early marker of human papillomavirus-driven oropharyngeal cancer (HPV-OPC), yet more sensitive imaging modalities are needed before screening is considered. The objective of this study was to determine the sensitivity of transcervical sonography (TCS) for detecting clinically apparent HPV-OPC in comparison with computed tomography (CT) and positron emission tomography (PET)/CT.

METHODS

Fifty-one patients with known or suspected HPV-OPC without prior treatment underwent oropharyngeal TCS and blood collection (for HPV multiplex serology testing). Eight standard sonographic images were collected; primary-site tumors were measured in 3 dimensions if identified. Each patient underwent a full diagnostic workup as part of standard clinical care. The pathologic details, HPV status, final staging, and imaging findings were abstracted from the medical record. The sensitivity of each imaging modality was compared with the final clinical diagnosis (the gold standard).

RESULTS

Twenty-four base of tongue cancers (47%), 22 tonsillar cancers (43%), and 2 unknown primary cancers (4%) were diagnosed; 3 patients (6%) had no tumors. All p16-tested patients were positive (n = 47). Primary-site tumors were correctly identified in 90.2% (95% confidence interval [CI], 78.6%-96.7%) with TCS, in 69.4% (95% CI, 54.6%-81.7%) with CT, and in 83.3% (95% CI, 68.6%-93.0%) with PET/CT. TCS identified tumors in 10 of 14 cases missed by CT and recognized the absence of tumors in 3 cases for which CT or PET/CT was falsely positive. The smallest sonographically identified primary-site tumor was 0.5 cm in its greatest dimension; the average size was 2.3 cm. Among p16-positive patients, 76.1% (95% CI, 61.2%-87.4%) were seropositive for HPV-16 E6.

CONCLUSIONS

TCS and HPV-16 E6 antibodies are sensitive for the diagnosis of HPV-OPC.