Viral load, physical status, and E6/E7 mRNA expression of human papillomavirus in head and neck squamous cell carcinoma

Biplex quantitative PCR to detect transcriptionally active human papillomavirus 16 from patient saliva

Head and neck cancers, particularly oropharyngeal cancers (OPC), have been increasingly associated with human papillomavirus (HPV) infections, specifically HPV16. The current methods for HPV16 detection primarily rely on p16 staining or PCR techniques. However, it is important to note the limitations of conventional PCR, as the presence of viral DNA does not always indicate an ongoing viral infection. Moreover, these tests heavily rely on the availability of tissue samples, which can present challenges in certain situations. In this study, we developed a RT-qPCR biplex approach to detect HPV16 oncogenes E6 and E7 RNA in saliva samples from OPC patients. Salivary supernatant was used as the liquid biopsy source. We successfully obtained RNA from salivary supernatant, preserving its integrity as indicated by the detection of several housekeeping genes. Our biplex approach accurately detected E6 and E7 RNA in HPV16-positive cell lines, tissues, and finally in OPC salivary samples. Importantly, the assay specifically targeted HPV16 and not HPV18. This biplexing technique allowed for reduced sample input without compromising specificity. In summary, our approach demonstrates the potential to detect viable HPV16 in saliva from OPC patients. Since the assay measures HPV16 RNA, it provides insights into the transcriptional activity of the virus. This could guide clinical decision-making and treatment planning for individuals with HPV-related OPC.

Human Papillomavirus Infection and EGFR Exon 20 Insertions in Sinonasal Inverted Papilloma and Squamous Cell Carcinoma

This study aimed to clarify the roles of high-risk human papillomavirus (HR-HPV) infection and epidermal growth factor receptor (EGFR) exon 20 mutations in sinonasal inverted papilloma (IP) and sinonasal squamous cell carcinoma (SNSCC). Samples were collected from 20 cases with IP, 7 with IP and squamous cell carcinoma (IP-SCC), and 20 with SNSCC and examined for HPV infection and EGFR exon 20 mutations. Low- or high-risk HPV DNA was observed in 25% of IP, 57.1% of IP-SCC, and 35% of SNSCC cases. Transcriptionally active HR-HPV infections in IP-SCC and SNSCC, accompanied by p16 overexpression, were observed in 28.5% and 25% of cases, respectively. Heterozygous EGFR exon 20 amino acid insertions (ex20ins), located between amino acids 768-774, were observed in 45% of IP, 28.5% of IP-SCC, and 0% of SNSCC and chronic sinusitis cases. EGFR phosphorylation sites were located at tyrosine (Y) 845, Y1068, Y1086, and Y1197 and induced PI3K/AKT/mTOR activation. The phosphorylation pattern of EGFR with ex20ins resembled that of HPV-related SNSCC and oropharyngeal cancer. The transcriptionally active HR-HPV infection and ex20ins might be responsible for the pathogenesis of IP-SCC cases with different fashions. Since IP-SCC might be a multifactorial disease, further investigation is needed to understand IP-SCC etiology.

Radiotherapy Plus Cetuximab for Squamous Cell Carcinoma of the Oral Cavity: A Multicenter Retrospective Study of 79 Patients in Japan

There are a few reports that focus on radiotherapy (RT) and cetuximab (CET) therapy exclusively for oral cancer. This retrospective study aimed to investigate the efficacy and safety of RT and CET therapy for locally advanced (LA) or recurrent/metastatic (R/M) oral squamous cell carcinoma (OSCC). Seventy-nine patients from 13 hospitals who underwent RT and CET therapy for LA or R/M OSCC between January 2013 and May 2015 were enrolled in the study. Response, overall survival (OS), disease-specific survival (DSS), and adverse events were investigated. The completion rate was 62/79 (78.5%). The response rates in patients with LA and R/M OSCC were 69% and 37.8%, respectively. When only completed cases were examined, the response rates were 72.2% and 62.9%, respectively. The 1- and 2-year OS were 51.5% and 27.8%, respectively (median, 14 months), for patients with LA OSCC, and 41.5% and 11.9% (median, 10 months) for patients with R/M OSCC. The 1- and 2-year DSS were 61.8% and 33.4%, respectively (median, 17 months), for patients with LA OSCC, and 76.6% and 20.4% (median, 12 months) for patients with R/M OSCC. The most common adverse event was oral mucositis (60.8%), followed by dermatitis, acneiform rash, and paronychia. The completion rate was 85.7% in LA patients and 70.3% in R/M patients. The most common reason for noncompletion was an inadequate radiation dose due to worsening general conditions in R/M patients. Although the standard treatment for LA or R/M oral cancer is concomitant RT with high-dose cisplatin (CCRT) and the efficacy of RT and CET therapy for oral cancer is not considered to be as high as that for other head and neck cancers, it was thought that RT and CET therapy could be possible treatments for patients who cannot use high-dose cisplatin.

Differences between Squamous Cell Carcinomas of the Base of the Tongue and the Tonsils in Prevalence of HPV16 Infection, Its Type, and Clinical Features

Regarding attempts to find de-escalation methods of treatment for patients with HPV16-positive squamous cell carcinoma of the oropharynx (OPSCC), there is an urgent need to identify new prognostic factors which allow physicians to differentiate the prognosis of these patients. The aim of the study is to compare the incidence of transcriptionally active HPV16 infection and its type as well as other epidemiological, clinical, and histopathological features between SCC of the base of the tongue (BOTSCC) and tonsils (TSSCC). The analysis was performed in a group of 63 patients with OPSCC, for which, in our earlier studies, we assessed transcriptionally active HPV16 infection and its type (viral load and viral genome status). Transcriptionally active HPV16 infection was significantly more common in TSSCC (96.3%) than in BOTSCC (3.7%). Patients with TSSCC had significantly higher disease-free survival rates (84.1%) than those with BTSCC (47.4%); the same was true in the subgroup with HPV16 positivity. The obtained results are an important indication for further research on the development of new prognostic and/or predictive factors for patients with HPV16-positive squamous cell carcinomas of the oropharynx.

Causal Link of Human Papillomavirus in Barrett Esophagus and Adenocarcinoma: Are We There Yet?

Esophageal cancer is a relatively common malignancy worldwide with a high mortality (5-year survival of <15%). Despite screening, surveillance, improved imaging and treatment, the exponential rise in OAC continues. The strongest risk factors for OAC are chronic heartburn and metaplastic transformation of the lower third of the esophagus (Barrett's esophagus). The risk profile includes Caucasian race, male gender older age, obesity and smoking. Although the tumor risk in BO has been progressively revised downwards, the exponential rise in OAC remains unchecked. This paradox points to an unidentified missing link. Relatively recently, we provided the world's initial data for a strong association of biologically relevant hr-HPV with BD and OAC. Since then, systematic reviews and meta-analysis have documented HPV DNA prevalence rates in OAC of between 13 to 35%. In this review, we provide some evidence for a probable causal relationship between hr-HPV and OAC. This is challenging given the multifactorial etiology and long latency. Increasingly, high-risk HPV (hr-HPV) is regarded as a risk factor for OAC. This discovery will aid identification of a sub-group of high-risk progressors to esophageal cancer by surveillance and the development of effective preventive strategies including vaccination.

Association of Tumor Site With the Prognosis and Immunogenomic Landscape of Human Papillomavirus-Related Head and Neck and Cervical Cancers

Importance

Human papillomavirus (HPV)-positive status in patients with oropharyngeal squamous cell carcinoma (OPSCC) is associated with improved survival compared with HPV-negative status. However, it remains controversial whether HPV is associated with improved survival among patients with nonoropharyngeal and cervical squamous cell tumors.

Objective

To investigate differences in the immunogenomic landscapes of HPV-associated tumors across anatomical sites (the head and neck and the cervix) and their association with survival.

Design, Setting, and Participants

This cohort study used genomic and transcriptomic data from the Cancer Genome Atlas (TCGA) for 79 patients with OPSCC, 435 with nonoropharyngeal head and neck squamous cell carcinoma (non-OP HNSCC), and 254 with cervical squamous cell carcinoma and/or endocervical adenocarcinoma (CESC) along with matched clinical data from TCGA. The data were analyzed from November 2020 to March 2021.

Main Outcomes and Measures

Positivity for HPV was classified by RNA-sequencing reads aligned with the HPV reference genome. Gene expression profiles, immune cell phenotypes, cytolytic activity scores, and overall survival were compared by HPV tumor status across multiple anatomical sites.

Results

The study comprised 768 patients, including 514 (66.9%) with HNSCC (380 male [73.9%]; mean [SD] age, 59.5 [10.8] years) and 254 (33.1%) with CESC (mean [SD] age, 48.7 [14.1] years). Human papillomavirus positivity was associated with a statistically significant improvement in overall survival for patients with OPSCC (adjusted hazard ratio [aHR], 0.06; 95% CI, 0.02-0.17; P < .001) but not for those with non-OP HNSCC (aHR, 0.64; 95% CI, 0.31-1.27; P = .20) or CESC (aHR, 0.50; 95% CI, 0.15-1.67; P = .30). The HPV-positive OPSCCs had increased tumor immune infiltration and immunomodulatory receptor expression compared with HPV-negative OPSCCs. Compared with HPV-positive non-OP HNSCCs, HPV-positive OPSCCs showed greater expression of immune-related metrics including B cells, T cells, CD8+ T cells, T-cell receptor diversity, B-cell receptor diversity, and cytolytic activity scores, independent of tumor variant burden. The immune-related metrics were similar when comparing HPV-positive non-OP HNSCCs and HPV-positive CESCs with their HPV-negative counterparts. The 2-year overall survival rate was significantly higher for patients with HPV-positive OPSCC compared with patients with HPV-negative OPSCC (92.0% [95% CI, 84.8%-99.9%] vs 45.8% [95% CI, 28.3%-74.1%]; HR, 0.10 [95% CI, 0.03-0.30]; P = .009).

Conclusions and Relevance

In this cohort study, tumor site was associated with the immune landscape and survival among patients with HPV-related tumors despite presumed similar biologic characteristics. These tumor site-related findings provide insight on possible outcomes of HPV positivity for tumors in oropharyngeal and nonoropharyngeal sites and a rationale for the stratification of HPV-associated tumors by site and the subsequent development of strategies targeting immune exclusion in HPV-positive nonoropharyngeal cancer.

Causes and Consequences of HPV Integration in Head and Neck Squamous Cell Carcinomas: State of the Art

A constantly increasing incidence in high-risk Human Papillomaviruses (HPV)s driven head and neck squamous cell carcinomas (HNSCC)s, especially of oropharyngeal origin, is being observed. During persistent infections, viral DNA integration into the host genome may occur. Studies are examining if the physical status of the virus (episomal vs. integration) affects carcinogenesis and eventually has further-reaching consequences on disease progression and outcome. Here, we review the literature of the most recent five years focusing on the impact of HPV integration in HNSCCs, covering aspects of detection techniques used (from PCR up to NGS approaches), integration loci identified, and associations with genomic and clinical data. The consequences of HPV integration in the human genome, including the methylation status and deregulation of genes involved in cell signaling pathways, immune evasion, and response to therapy, are also summarized.

Chemopotentiating effects of low-dose fractionated radiation on cisplatin and paclitaxel in cervix cancer cell lines and normal fibroblasts from patients with cervix cancer

The aim of the present study was to compare the effects (assessed by clonogenic survival and γH2AX foci assays) of low-dose fractionated radiation LDFR (4 × 0.125 Gy, 4 × 0.25 Gy and 4 × 0.5 Gy) versus single radiation doses (0.5 Gy, 1 Gy and 2 Gy) on cisplatin and paclitaxel in HRS-negative cervix cancer cell lines SiHa and CaSki to see if the effects of LDFR can emerge in cells that not present low-dose hyper-radiosensitivity (HRS) phenomenon. Additionally, we report the effects in normal fibroblasts (HRS-negative and HRS-positive) from two patients with cervix cancer to see if the chemopotentiating effects of LDFR also apply to normal cells. LDFR (4 × 0.125 Gy, 4 × 0.25 Gy and 4 × 0.5 Gy) as well as single doses (0.5 Gy, 1 Gy and 2 Gy) enhanced cytotoxicity of cisplatin and paclitaxel in all the cell lines. Cisplatin-potentiating effects were maximum with LDFR 4 × 0.5 Gy, and were two-fold greater than those with a single dose of 2 Gy in SiHa, CaSki and HFIB2 cells. Paclitaxel-enhancing effects were also maximum with LDFR 4 × 0.5 Gy, however only in HRS-positive HFIB2 fibroblasts were significantly greater than those with a single dose of 2 Gy. The results demonstrate that LDFR may enhance the effects of cisplatin and paclitaxel in SiHa and CaSki cells, although they lack HRS phenomenon, and show that the magnitude of the potentiating effects of LDFR depends on cytostatic type and the size of low doses. In normal fibroblasts the chemopotentiating effects of LDFR seem to depend on HRS status. In conclusion, the unique enhancing effects of LDFR on cisplatin in cervical cancer cell lines, even when HRS negative, suggest that all patients with cervical cancer may benefit from the addition of LDFR to adjuvant cisplatin-based chemotherapy.

Detection of human papillomavirus in oropharyngeal squamous cell carcinoma

Worldwide there has been a significant increase in the incidence of oropharyngeal squamous cell carcinoma (OPSCC) etiologically attributed to oncogenic human papillomavirus (HPV). Reliable and accurate identification and detection tools are important as the incidence of HPV-related cancer is on the rise. Several HPV detection methods for OPSCC have been developed and each has its own advantages and disadvantages in regard to sensitivity, specificity, and technical difficulty. This review summarizes our current knowledge of molecular methods for detecting HPV in OPSCC, including HPV DNA/RNA polymerase chain reaction (PCR), loop-mediated isothermal amplification (LAMP), p16 immunohistochemistry (IHC), and DNA/RNA in situ hybridization (ISH) assays. This summary may facilitate the selection of a suitable method for detecting HPV infection, and therefore may help in the early diagnosis of HPV-related carcinoma to reduce its mortality, incidence, and morbidity.

Human Papillomavirus in Sinonasal Squamous Cell Carcinoma: A Systematic Review and Meta-Analysis

Simple Summary

The causative role of human papillomavirus (HPV) in sinonasal squamous cell carcinoma (SNSCC) remains unclear and is hindered by small studies using variable HPV detection techniques. This meta-analysis aims to provide an updated overview of HPV prevalence in SNSCC stratified by detection method, anatomic subsite, and geographic region. From 60 eligible studies, an overall HPV prevalence was estimated at 26%. When stratified by detection method, HPV prevalence was lower when using multiple substrate testing compared to single substrate testing. Anatomic subsite HPV prevalence was higher in subsites with high exposure to secretion flow compared to low exposure subsites. HPV prevalence in SNSCC followed the global distribution of HPV+ oropharyngeal squamous cell carcinoma. Taken together, this meta-analysis further supports a role for HPV in a subset of SNSCCs.

Abstract

Human papillomavirus (HPV) drives tumorigenesis in a subset of oropharyngeal squamous cell carcinomas (OPSCC) and is increasing in prevalence across the world. Mounting evidence suggests HPV is also involved in a subset of sinonasal squamous cell carcinomas (SNSCC), yet small sample sizes and variability of HPV detection techniques in existing literature hinder definitive conclusions. A systematic review was performed by searching literature through March 29th 2020 using PubMed, Embase, and Web of Science Core Collection databases. Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were followed by two authors independently. A meta-analysis was performed using the random-effects model. Sixty studies (n = 1449) were eligible for statistical analysis estimating an overall HPV prevalence of 25.5% (95% CI 20.7–31.0). When stratified by HPV detection method, prevalence with multiple substrate testing (20.5%, 95% CI 14.5–28.2) was lower than with single substrate testing (31.7%, 95% CI 23.6–41.1), highest in high-exposure anatomic subsites (nasal cavity and ethmoids) (37.6%, 95% CI 26.5–50.2) vs. low-exposure (15.1%, 95% CI 7.3–28.6) and highest in high HPV+ OPSCC prevalence geographic regions (North America) (30.9%, 95% CI 21.9–41.5) vs. low (Africa) (13.1, 95% CI 6.5–24.5)). While small sample sizes and variability in data cloud firm conclusions, here, we provide a new reference point prevalence for HPV in SNSCC along with orthogonal data supporting a causative role for virally driven tumorigenesis, including that HPV is more commonly found in sinonasal subsites with increased exposure to refluxed oropharyngeal secretions and in geographic regions where HPV+ OPSCC is more prevalent.

Droplet digital PCR quantification suggests that higher viral load correlates with improved survival in HPV-positive oropharyngeal tumours

BACKGROUND

Although HPV-positive oropharyngeal cancer (OPC) patients have improved prognosis compared to HPV negative patients; there remains an HPV-positive group who have poor outcomes. Biomarkers to stratify discrete patient outcomes are thus desirable. Our objective was to analyse viral load (VL) by droplet digital PCR (ddPCR), in HPV-positive patients with OPC on whom clinical outcome data were available.

METHODS

In a cohort of patients that had previously tested HPV positive via conventional PCR, VL was determined using ddPCR assays for HPV16 L1 and E6 genes. VL was classed as "medium/high" if more than 5.57 copies or 8.68 copies of the HPV 16 L1 or E6 gene were detected respectively. Effect of VL on overall survival and hazard of death & disease progression was performed with adjustments made for sex, age, deprivation, smoking, alcohol consumption and stage.

RESULTS

L1 VL ranged from 0.0014-304 gene copies per cell with a mean of 30.9; comparatively E6 VL ranged from 0.0012-356 copies per cell with a mean of 37.9. Univariate analysis showed those with a medium/high VL had a lower hazard of death; this was significant for L1 (p = 0.02) but not for E6 (p = 0.67). The ratio of E6 to L1 deviated from n = 1 in most samples but had no influence on clinical outcomes.

CONCLUSIONS

HPV viral load may be informative for the further stratification of clinical outcomes in HPV positive OPC patients.

Importance of investigating high-risk human papillomavirus in lymph node metastasis of esophageal adenocarcinoma

High-risk human papillomavirus has been suggested as a risk factor for esophageal adenocarcinoma. Tumor human papillomavirus status has been reported to confer a favorable prognosis in esophageal adenocarcinoma. The size of the primary tumor and degree of lymphatic spread determines the prognosis of esophageal carcinomas. Lymph node status has been found to be a predictor of recurrent disease as well as 5-year survival in esophageal malignancies. In human papillomavirus driven cancers, e.g. cervical, anogenital, head and neck cancers, associated lymph nodes with a high viral load suggest metastatic lymph node involvement. Thus, human papillomavirus could potentially be useful as a marker of micro-metastases. To date, there have been no reported studies regarding human papillomavirus involvement in lymph nodes of metastatic esophageal adenocarcinoma. This review highlights the importance of investigating human papillomavirus in lymph node metastasis of esophageal adenocarcinoma based on data derived from other human papillomavirus driven cancers.

Detailed Characteristics of Tonsillar Tumors with Extrachromosomal or Integrated Form of Human Papillomavirus

The human papillomavirus (HPV) integration, the critical step in viral carcinogenesis, most frequently occurs in the E2 gene, which results in its inactivation and in an increase of E6/E7 transcription. However, in a substantial number of tumors, the virus is present in an extrachromosomal form. For those tumors, the transformation mechanisms are not fully elucidated. Here we evaluated the possible mechanism of inactivating the E2 without interruption of the gene, methylation or mutation of the E2 binding sites (E2BSs) in HPV16-positive tonsillar tumors by next-generation and Sanger sequencing. Viral genome status was analyzed by the amplification of papillomavirus oncogene transcripts assay (APOT) and mRNA mapping, and expression of viral oncogenes was performed by qPCR. The methylation of E2BSs was significantly higher in tumors with an integrated, in comparison to extrachromosomal, form of the viral genome. No mutations were detected in the E2BSs. The viral oncogenes were equally expressed in samples with an integrated and extrachromosomal form of the virus. Only the nucleotide variants were identified in the E2 gene. No proposed mechanism of E2 inactivation was confirmed in tonsillar tumors with an extrachromosomal form of the HPV genome. The expression of E6/E7 genes seems to be sufficient to initiate and maintain the carcinogenic process.

Unlocking the Potential of Saliva-Based Test to Detect HPV-16-Driven Oropharyngeal Cancer

The incidence of human papillomavirus (HPV)-positive oropharyngeal cancer (OPC) is rising in high-income countries, including Australia. Increasing evidence suggests that accurate HPV testing is pivotal for clinical decision making and treatment planning in these patients. Recently, the eighth edition of the American Joint Committee on Cancer/Union for International Cancer Control (AJCC/UICC) tumor-node-metastasis (TNM) staging system for OPC (based on the p16INK4a (p16) status) was proposed and has been implemented. However, the applicability of this new staging system is still far from clear. In our study, n = 127 OPC patients from Queensland, Australia were recruited, and the tumor p16 expression in these patients was examined using immunohistochemical (IHC) analysis. HPV-16 genotyping, viral load, and physical status (episomal versus integrated) in the saliva samples of OPC patients were determined using the qPCR method. A good inter-rater agreement (k = 0.612) was found between tumor p16 expression and oral HPV-16 infection in OPC. Importantly, according to the eighth edition staging system, HPV-16 DNA viral load (>10 copies/50 ng) was significantly associated with the advanced stages of OPC. In concordance with previous studies, a mixed HPV-16 form (partially or fully integrated) was predominately found in OPC patients. Taken together, our data support HPV-16 detection in saliva as a screening biomarker to identify people within the community who are at risk of developing OPC.

A novel human in vitro papillomavirus type 16 positive tonsil cancer cell line with high sensitivity to radiation and cisplatin

Background

Human papillomavirus (HPV) is an established risk factor for oropharyngeal squamous cell carcinoma (OSCC). The aim was to establish cell lines from HPV-positive tonsil carcinomas to be used for treatment development.

Methods

Fresh samples from 23 HPV-positive tonsil carcinomas were cultivated in vitro. The established cell line was analyzed for viral characteristics, cell karyotype, TP53 status, and growth capabilities in nude mice. In vitro studies of sensitivities to radiation, cisplatin and cetuximab were performed.

Results

After 19 months (eight passages), one cell line, LU-HNSCC-26, was established in vitro and also grew as xenografts. The tumor was from a 48 year old non-smoking man with non-keratinizing, p16 positive tonsil OSCC, stage T2N0M0 with HPV16. It contained 19.5 (CV% 3.7) HPV16 copies/cell (passage 8). The complete HPV16 genome sequence was obtained. Episomal HPV16 was present with an E2/E7 ratio of 1.1 (CV% 2.6). In addition, HPV16 mRNA specific for the intact E2 gene was detected. The viral expression manifested 1.0 (CV% 0.1) E7 mRNA copies per HPV16 genome. The karyotype was determined and the cell line demonstrated wild type TP53. The ID50 for radiation was 0.90 Gy and the IC50 for cisplatin was 0.99 μmol/L. The cell line was inhibited to a maximum of 18% by cetuximab.

Conclusions

We established an in vitro tonsil carcinoma cell line containing episomal HPV16. This is an important step towards efficient treatment development.

Electronic supplementary material

The online version of this article (10.1186/s12885-019-5469-8) contains supplementary material, which is available to authorized users.

High-risk type human papillomavirus infection and p16 expression in laryngeal cancer

Background

Oropharyngeal cancers associated with high-risk type human papillomavirus (HR-HPV) infection have better prognosis than virus negative cancers. Similarly, the HPV status in laryngeal cancer (LC) may be associated with better outcome.

Methods

Samples from 88 patients with LC were investigated using the polymerase chain reaction (PCR) and p16 immunohistochemistry for HR-HPV analysis. The cut-off point for p16 overexpression was diffuse (≥75%) tumor expression with at least moderate (+ 2/3) staining intensity.

Results

The 5-year cumulative survival (CS) rate was 80.7% in all patients with LC. According to a combination of HR-HPV DNA status and p16 overexpression, subjects with LC were divided into four groups: HR-HPV DNA-positive/p16 overexpression-positive (n = 5, 5.7%; CS = 100%), HR-HPV DNA-positive/p16 overexpression-negative (n = 11, 12.5%; CS =81.8%), HR-HPV DNA-negative/p16 overexpression-positive (n = 0), and HR-HPV DNA-negative/p16 overexpression-negative (n = 72, 81.8%; CS = 79.5%). HR-HPV DNA-positive/p16-positive cases tended to have integrated HPV infection and high viral load, compared with HR-HPV DNA-positive/p16 overexpression-negative cases.

Conclusions

LC patients with HPV infection and high levels of p16 expression might have an improved survival outcome; however, it is necessary to recruit additional LC cases with HPV infection to determine the definitive characteristics of HPV-mediated LC and estimate survival outcome. These results may contribute to the development of a useful method for selecting patients with a potentially fair response to treatment and ensure laryngeal preservation.

Staging and prognosis of oropharyngeal carcinoma according to the 8th Edition of the American Joint Committee on Cancer Staging Manual in human papillomavirus infection

PURPOSE

The aim of this study was to evaluate the 8th edition of the American Joint Committee on Cancer Staging Manual: Head and Neck Section on oropharyngeal squamous cell cancer (OPSCC) and to clarify the relationship between p16 overexpression and the presence of human papillomavirus (HPV) DNA using fresh frozen samples.

METHODS

Samples from 100 OPSCC patients were analyzed using polymerase chain reaction (PCR) and p16 immunohistochemistry.

RESULTS

Five-year overall survival (OS) was 73.0%, 93.9%, and 62.2% in all, p16-positive (n = 34), and p16-negative (n = 66) cases, respectively. OS tended to be better aligned with stage in the 8th edition than in the 7th edition. The 5-year OS was 96.0% in never or light smokers (< 40 pack-years), and 87.5% in heavy smokers (≥ 40 pack-years) in the p16-positive group, respectively (p = 0.027). HPV infection was found in 100% of p16-positive and 21.2% of p16-negative cases. The p16-positive cases had higher viral load and integrated physical status than the p16-negative cases. Although 1 case with p16 overexpression showed no PCR amplification using consensus primers, PCR amplification was detected using HPV 16 E6-specific primers.

CONCLUSIONS

The 8th edition predicts OPSCC prognosis more accurately than the 7th edition and p16-overexpression is an excellent surrogate marker for detecting HPV infection. Although high-risk-type HPV infection was observed in p16-negative cases, it showed no significant effect in survival outcome.

Detection of circulating HPV16 DNA as a biomarker in the blood of patients with human papillomavirus-positive oropharyngeal squamous cell carcinoma

BACKGROUND

Development of biomarker analysis using the circulating cell-free DNA (cfDNA) methodology is a challenge for noninvasive cancer diagnosis. In this study, a comparison between the plasma and tumor tissue HPV16 DNA viral loads (VLs) has been presented.

METHODS

Real-time polymerase chain reaction was performed for quantitating of HPV16 DNA in the plasma and tumor samples of patients with oropharyngeal cancer.

RESULTS

Among the tissues, HPV16-positive patients with oropharyngeal squamous cell carcinoma, nonsmoking patients, displayed significantly higher HPV16 DNA VLs in their tissue. No smoking and advanced N disease were the most important predictors for cHPV16 DNA (circulating HPV16 DNA) detection. The cHPV16-positive women displayed significantly higher VLs in their tumor tissues compared to the men, although without notable impact on the blood detection.

CONCLUSIONS

Many factors were responsible for human papillomavirus DNA circulation in blood. As a result of the small size of the analyzed group, some observed discrepancies need to be proven on a larger cohort.

Human papillomavirus in head and neck squamous cell carcinomas in a South African cohort

BACKGROUND

Most tumours of the head and neck are attributable to smoking and alcohol use, but an increasing proportion of head and neck tumours are caused by human papillomaviruses (HPVs). The aim of this study was to use in house molecular assays to detect and genotype HPV in biopsies from patients with histologically confirmed head and neck squamous cell carcinomas. In addition, the results were compared with p16 immunohistochemistry staining, which has been described as a potential marker for HPV infection.

METHODS

Biopsies of squamous cell carcinomas of the oropharynx, nasopharynx, larynx and hypopharynx from 112 South African patients were screened using three PCR assays targeting the L1 and E6 regions of HPV and p16 immunohistochemical staining.

RESULTS AND CONCLUSION

HPV was identified in 7 (6.3%) tumours, while 22 (19.6%) had positive p16 immunohistochemical staining. There was concordance between the results obtained using the three PCR assays. There was substantial agreement between the results of molecular tests and p16 immunohistochemistry for hypopharyngeal carcinomas, but only fair agreement for laryngeal and oropharyngeal carcinomas.

HPV-16 viral load in oropharyngeal squamous cell carcinoma using digital PCR

CONCLUSIONS

We did not identify any strong associations between HPV-16 viral load and any of the clinical or lifestyle factors.

OBJECTIVE

The epidemiology of oropharyngeal SCC is changing, with an increasing proportion of HPV-positive cases seen in the last decade. It is known that a high viral load is linked to the development of cervical cancer, the relation between viral load and oropharyngeal SCC is less clear. We sought to determine HPV-16 viral load in HPV-positive oropharyngeal SCCs using highly sensitive digital PCR and to identify clinical and lifestyle factors associated with viral load.

SUBJECTS AND METHODS

We analysed 45 HPV-16 positive oropharyngeal SCCs diagnosed between 2013 and 2015. All patients completed a lifestyle questionnaire and clinical data were extracted from medical charts. Viral load was determined using digital PCR assays for HPV-L1 and RNAseP.

RESULTS

We found large variations in HPV-16 viral load from 1 to 930 copies per cell (median 34 copies per cell).

Viral DNA integration and methylation of human papillomavirus type 16 in high-grade oral epithelial dysplasia and head and neck squamous cell carcinoma

This study evaluated the integration and methlyation of human papillomavirus type 16 (HPV16) in head and neck squamous cell carcinoma (HNSCC) and its oral precursor, high-grade oral epithelial dysplasia (hgOED). Archival samples of HPV16-positive hgOED (N = 19) and HNSCC (N = 15) were evaluated, along with three HNSCC (UMSCC-1, -47 and -104) and two cervical cancer (SiHa and CaSki) cell lines. HgOED cases were stratified into three groups with increasing degrees of cytologic changes (mitosis, karyorrhexis and apoptosis). The viral load was higher and the E2/E6 ratio lower (indicating a greater tendency toward viral integration) in group 3 than in groups 1 or 2 (p = 0.002, 0.03). Methylation was not observed in hgOED cases and occurred variably in only three HNSCC cases (26.67%, 60.0% and 93.3%). In HNSCC cell lines, lower E7 expression correlated with higher levels of methylation. HgOED with increased cytologic change, now termed HPV-associated oral epithelial dysplasia (HPV-OED), exhibited an increased viral load and a tendency toward DNA integration, suggesting a potentially increased risk for malignant transformation. More detailed characterization and clinical follow-up of HPV-OED patients is needed to determine whether HPV-OED is a true precursor to HPV-associated HNSCC and to clarify the involvement of HPV in HNSCC carcinogenesis.

Detection of human papillomavirus in branchial cleft cysts

High-risk human papillomavirus (HPV) DNA has been reported to be present in branchial cleft cysts, but further information is required to clarify the role of HPV infection in branchial cleft cysts. The presence of HPV, the viral load and the physical statuses in samples from six patients with branchial cleft cysts were investigated using the polymerase chain reaction (PCR), quantitative PCR, in situ hybridization (ISH) using HPV DNA probes and p16^INK4a immunohistochemical analysis. High-risk type HPV-16 DNA was identified in four of the six branchial cleft cysts analyzed. Of the HPV-positive branchial cleft cysts, three exhibited mixed-type integration of HPV. HPV DNA was distributed among the basal-to-granular layers of the cystic wall in ISH analysis, and p16^INK4a was weakly expressed in the nuclei and cytoplasm of the same layers in patients with integration. ISH revealed that one patient with episomal-type infection exhibited HPV DNA in the cyst wall and did not express p16^INK4a. Two patients without evidence of HPV infection exhibited weak p16^INK4a expression in the superficial cyst-lining cells of branchial cleft cysts. These results indicate that infection with high-risk HPV types may be common in branchial cleft cysts. In addition, p16^INK4a is not a reliable surrogate marker for HPV infection in branchial cleft cysts.

Human papillomavirus type 16 (HPV16) DNA copy number in oral rinse samples from oral cavity cancer patients

Objectives:

The objective of this study is to examine the human papillomavirus type 16 (HPV16) DNA copy number in the oral cavity of cancer patients using oral rinse samples.

Methods:

We analyzed the HPV16 DNA copy number of oral rinse samples in 13 primary oral cavity cancer patients (mean age 67.8 years, range 48–84 years) who visited the Department of Oral and Maxillofacial Reconstructive Surgery of Hiroshima University Hospital (Hiroshima, Japan). The 13 oral cavity cancers included 6 carcinomas in situ and 7 squamous cell carcinomas. Real-time PCR analysis was performed to examine the number of HPV16 E6 viral copies in oral rinse samples. Additionally, the HPV16 integration status was investigated using the real-time PCR findings for HPV16 E2 genes in HPV16 E6-positive oral rinse samples.

Results:

HPV16 E6 copy numbers above the detection limit in a standard curve for HPV16 E6 DNA were assessed as HPV16 positive in oral rinse samples from 6 of 13 patients. The average number of HPV16 E6 viral copies was 1.71 ± 1.72 per cell (range, 0.39–4.96 copies/cell) in six oral rinse samples. The HPV16 E2 viral load was detected in four of the six HPV16-positive oral rinse samples. Two of the six HPV16-positive oral rinse samples showed HPV16 E2 copy numbers below the detection limit, indicating the full integration of HPV16 DNA.

Conclusions:

The number of patients in this study was small; therefore, further investigation using a larger number of participants is required to clarify the level of HPV16 viral copy number in the oral cavity of cancer patients.

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.

Association of an intact E2 gene with higher HPV viral load, higher viral oncogene expression, and improved clinical outcome in HPV16 positive head and neck squamous cell carcinoma

To assess the relationship of E2 gene disruption with viral gene expression and clinical outcome in human papillomavirus (HPV) positive head and neck squamous cell carcinoma, we evaluated 31 oropharyngeal and 17 non-oropharyngeal HPV16 positive carcinomas using two PCR-based methods to test for disruption of E2, followed by Sanger sequencing. Expression of HPV16 E6, E7 and E2 transcripts, along with cellular ARF and INK4A, were also assessed by RT-qPCR. Associations between E2 disruption, E2/E6/E7 expression, and clinical outcome were evaluated by Kaplan-Meier analysis for loco-regional recurrence and disease-specific survival. The majority (n = 21, 68%) of HPV16 positive oropharyngeal carcinomas had an intact E2 gene, whereas the majority of HPV16 positive non-oropharyngeal carcinomas (n = 10, 59%) had a disrupted E2 gene. Three of the oropharyngeal tumors and two of the non-oropharyngeal tumors had deletions within E2. Detection of an intact E2 gene was associated with a higher DNA viral load and increased E2/E6/E7, ARF and INK4A expression in oropharyngeal tumors. Oropharyngeal carcinomas with an intact E2 had a lower risk of loco-regional recurrence (log-rank p = 0.04) and improved disease-specific survival (p = 0.03) compared to tumors with disrupted E2. In addition, high E7 expression was associated with lower risk of loco-regional recurrence (p = 0.004) as was high E6 expression (p = 0.006). In summary, an intact E2 gene is more common in HPV16 positive oropharyngeal than non-oropharyngeal carcinomas; the presence of an intact E2 gene is associated with higher HPV viral load, higher viral oncogene expression, and improved clinical outcome compared to patients with a disrupted E2 gene in oropharyngeal cancer.

The prevalence of human papillomavirus in oropharyngeal cancer in a New Zealand population

BACKGROUND

The incidence of oropharyngeal cancer (OPC) in New Zealand (NZ) has more than doubled over the last 14 years with 126 cases in 2010. Overseas studies have shown that human papillomavirus (HPV) plays a significant role in the development of these cancers. However, the role of HPV in OPC and the burden on the NZ health system is unclear.

AIM

The aim of the study was to determine the prevalence and the genotypes of HPV associated with OPC in New Zealand.

METHODS

In this study, 621 OPC were identified from cancer registry data from 1996-98, 2003-05, and 2010-12. Biopsies of 267 cases were then retrieved from laboratories throughout New Zealand. p16 immunohistochemistry and a human beta globin PCR were performed on all specimens. HPV genotyping was performed on all beta globin positive specimens using real-time PCR with melt analysis.

RESULTS

Using a p16/PCR algorithm, 77.9% (95% CI: 71.1-83.5%) of cases were attributable to HPV. Of these, 98.5% were HPV 16 positive. There was also one case each of HPV 33 and 35. The percentage of HPV positive cases increased from 61.9% (95% CI: 40.9%- 79.2%) in 1996-98 to 87.5% (95% CI: 79.8%- 92.5%) in 2010-12. Results from the multivariable model, adjusted for sex and ethnicity found statistically significant associations between HPV positivity and timeframe (OR: 5.65, 95% CI: 2.60-12.30, 2010-12 vs 1996-98), and between HPV positivity and patient age (OR: 0.55, 95% CI: 0.33-0.99, ≥61 years vs ≤60 years).

CONCLUSIONS

This data is consistent with data from other developed countries showing an increase in cases of HPV positive OPC in New Zealand, and the majority of cases being attributable to HPV 16. These results support the recent inclusion of males into the nationally funded immunization schedule for Gardasil® 9.

Differences in the prognosis of HPV16-positive patients with squamous cell carcinoma of head and neck according to viral load and expression of P16

Purpose

To evaluate the impact of HPV16 load (VL—the number of virus genome copies per cell) and P16 expression on prognosis of patients with squamous cell carcinomas (SCCs) of head and neck (HN).

Materials and methods

HPV16 presence was assessed in the group of 109 patients with HNSCCs by quantitative polymerase chain reaction (qPCR). VL (assessed by qPCR) and P16 expression (evaluated by immunohistochemistry) were analysed only in the subgroup of HPV16-positive tumours. These features were correlated with 5-year overall survival (OS) and disease-free survival (DFS).

Results

HPV16 infection was found in 36 tumours (33.0%). Virus-positive patients had better OS and DFS than those without infection (P = 0.041 and 0.005). Among HPV16-positive HNSCCs, 18 (50.0%) had higher VL (median value > 6764.3 copies/cell) and 25 (73.5%) P16 over expression. The significant differences in OS and DFS (P = 0.008 and 0.004) were noticed according to VL, wherein 100% DFS was found for patients with higher VL. According to P16 expression, significant difference was found only for OS (P = 0.020). In multivariate analysis, VL (P = 0.045; HR = 2.795; CI 0.121–1.060) and the level of smoking (P = 0.023, HR = 2.253; CI 1.124–4.514) were independent factors affecting DFS of HPV16-positive patients.

Conclusion

On the basis of viral load, it is possible to differentiate prognosis of patients with HPV16-positive HNSCCs. In this subgroup, viral load has stronger prognostic potential than P16 expression.

Methylation of CpG sites in the upstream regulatory region, physical status and mRNA expression of HPV-6 in adult-onset laryngeal papilloma

The methylation status of HPV-6 upstream regulatory region (URR) in adult-onset laryngeal papillomatosis (AO-LP) remains unclear. The purpose of this study was to investigate the methylation status of URR and the physical status of HPV-6, as well as the dynamic variations of viral load and mRNA expression in AO-LP. We examined 18 specimens from 11 patients with AO-LP by real-time polymerase chain reaction (PCR), bisulfite-sequencing PCR, and amplification of papilloma oncogene transcripts. HPV-6 was identified in 9 of 11 patients (81.8%), and all the 15 specimens derived from 9 HPV-6-positive cases contained only episomal HPV-6 transcripts with intact E2. Three HPV-6-positive patients developed recurrent lesions, and HPV-6 copy numbers and mRNA expression decreased after surgical treatment. Among the 96 CpG sites (16/case), 67 (69.8%) were unmethylated, while 23 (30.2%) were heterogeneous (≥ 1 methylated CpG clone). High viral loads and episomal status of HPV-6 were frequently observed in AO-LP; thus, persistent E6/E7 mRNA expression of LR-HPV-6 may be associated with AO-LP recurrences. Hypomethylation and scattered patterns of methylated CpGs at the URR of HPV-6 were identified in AO-LP.

Proportion of transcriptionally active DNA virus integrants: a meta-analysis

Oncoviruses are collectively responsible for over 1,000,000 new cases of cancer per year; some can integrate into the host's chromosomes. The present work was aimed at assessing the proportion of transcriptionally active viral integrants through a systematic review of the scientific publications present on the MedLine database. From the articles screened, 628 viral integrants overall were retrieved, of which 530.84 were transcriptionally active (84.53%); among the clinical samples, 264 of 323 integrants were active (81.73%). The causes for the silencing were not addressed in the articles analyzed. These findings might highlight a possible risk factor for the insurgence of cancer since some oncovirus integrants could be reactivated by stimuli of disparate nature. Further studies should address such possibility.

Human papillomavirus dysregulates the cellular apparatus controlling the methylation status of H3K27 in different human cancers to consistently alter gene expression regardless of tissue of origin

High-risk human papillomaviruses (HPV) cause cancer at multiple distinct anatomical locations. Regardless of the tissue of origin, most HPV positive (HPV+) cancers show highly upregulated expression of the p16 product of the cyclin-dependent kinase inhibitor 2A (CDKN2A) gene. Paradoxically, HPV+ tumor cells require continuous expression of this tumor suppressor for survival. Thus, restoration of normal p16 regulation has potential therapeutic value against HPV induced cancers. Normally, p16 transcription is tightly controlled at the epigenetic level via polycomb repressive complex-mediated tri-methylation of histone 3 lysine 27 (H3K27me3). Although a mechanism by which HPV induces p16 has been proposed based on tissue culture models, it has not been extensively validated in human tumors. In this study, we used data from over 800 human cervical and head and neck tumors from The Cancer Genome Atlas (TCGA) to test this model. We determined the impact of HPV status on expression from the CDKN2A locus, the adjacent CDKN2B locus, and transcript levels of key epigenetic regulators of these loci. As expected, HPV+ tumors from both anatomical sites exhibited high levels of p16. Furthermore, HPV+ tumors expressed higher levels of KDM6A, which demethylates H3K27me3. CpG methylation of the CDKN2A locus was also consistently altered in HPV+ tumors. This data validates previous tissue culture studies and identifies remarkable similarities between the effects of HPV on gene expression and DNA methylation in both cervical and oral tumors in large human cohorts. Furthermore, these results support a model whereby HPV-mediated dysregulation of CDKN2A transcription requires KDM6A, a potentially druggable target.

Integration of Human Papillomavirus Genomes in Head and Neck Cancer: Is It Time to Consider a Paradigm Shift?

Human papillomaviruses (HPV) are detected in 70–80% of oropharyngeal cancers in the developed world, the incidence of which has reached epidemic proportions. The current paradigm regarding the status of the viral genome in these cancers is that there are three situations: one where the viral genome remains episomal, one where the viral genome integrates into the host genome and a third where there is a mixture of both integrated and episomal HPV genomes. Our recent work suggests that this third category has been mischaracterized as having integrated HPV genomes; evidence indicates that this category consists of virus–human hybrid episomes. Most of these hybrid episomes are consistent with being maintained by replication from HPV origin. We discuss our evidence to support this new paradigm, how such genomes can arise, and more importantly the implications for the clinical management of HPV positive head and neck cancers following accurate determination of the viral genome status.

Physical state and copy numbers of HPV16 in oral asymptomatic infections that persisted or cleared during the 6-year follow-up

Persistent human papillomavirus (HPV) infection is a key event in HPV-induced carcinogenesis. As part of the prospective Finnish Family HPV Study, we analysed the physical state and viral copy numbers of HPV16 in asymptomatic oral infections that either persisted or cleared during the 6-year follow-up. The persister group comprised 14 women and 7 men with 51 and 21 HPV16-positive brush samples. The clearance group included 41 women and 13 men, with 64 and 24 samples, respectively. Physical state and viral DNA load were assessed by using quantitative PCR for HPV16 E2 and E6 genes. E2/E6 ratio was calculated and HPV16 was classified as episomal, mixed or integrated with values of 0.93-1.08, <0.93 and 0, respectively. In both genders, the physical state of HPV16 was significantly different between the cases and controls (P<0.001). HPV16 was episomal in all men and 66 % (27/41) of women who cleared their infection. HPV16 was mixed and/or integrated in71 % and 57 %of the women and men persisters, respectively. The mean HPV16 copy number per 50 ng genomic DNA was nearly 5.5-fold higher in the women than in the men clearance group (P=0.011). Only in men, HPV16 copy numbers were higher in persisters than in the clearance group (P=0.039). To conclude, in both genders, persistent oral HPV16 infections were associated with the mixed or integrated form of HPV16, while in the clearance groups, episomal HPV16 predominated. This indicates that HPV16 integration is a common event even in asymptomatic oral infections, which might predispose the infected subjects to progressive disease.

Integration of high-risk human papillomavirus into cellular cancer-related genes in head and neck cancer cell lines

BACKGROUND

Human papillomavirus (HPV)-positive oropharyngeal cancer is generally associated with excellent response to therapy, but some HPV-positive tumors progress despite aggressive therapy. The purpose of this study was to evaluate viral oncogene expression and viral integration sites in HPV16- and HPV18-positive squamous cell carcinoma lines.

METHODS

E6/E7 alternate transcripts were assessed by reverse transcriptase-polymerase chain reaction (RT-PCR). Detection of integrated papillomavirus sequences (DIPS-PCR) and sequencing identified viral insertion sites and affected host genes. Cellular gene expression was assessed across viral integration sites.

RESULTS

All HPV-positive cell lines expressed alternate HPVE6/E7 splicing indicative of active viral oncogenesis. HPV integration occurred within cancer-related genes TP63, DCC, JAK1, TERT, ATR, ETV6, PGR, PTPRN2, and TMEM237 in 8 head and neck squamous cell carcinoma (HNSCC) lines but UM-SCC-105 and UM-GCC-1 had only intergenic integration.

CONCLUSION

HPV integration into cancer-related genes occurred in 7 of 9 HPV-positive cell lines and of these 6 were from tumors that progressed. HPV integration into cancer-related genes may be a secondary carcinogenic driver in HPV-driven tumors. © 2017 Wiley Periodicals, Inc. Head Neck 39: 840-852, 2017.

Low prevalence of human papillomavirus in head and neck squamous cell carcinoma in the northwest region of the Philippines

BACKGROUND

Geographic heterogeneity of human papillomavirus (HPV) involvement in head and neck squamous cell carcinoma (HNSCC) has been observed over the last few years. This trend has not been evaluated in the Philippines. Hence, this study aims to provide for the first time a data on the prevalence of HPV in HNSCC in the northwestern region of the Philippines.

METHODS

Two hundred one (201) biopsy samples (179 formalin fixed paraffin embedded and 22 fresh frozen) from 163 Filipino HNSCC cases (oral cavity = 88; larynx = 60; oropharynx = 15) diagnosed between 2003 to 2013 were initially included in this study. HPV DNA was detected by two methods: (1) BSGP5+/6+-PCR/ multiplex human papillomavirus genotyping and (2) TaqMan probes-based real-time qPCR. Presence of HPV type-specific transcripts were also analyzed by reverse transcription-PCR with subsequent hybridization to oligonucleotide probes coupled to Luminex beads. Co-amplification of the β-globin and ubiquitin C genes served as internal positive controls for DNA and RNA analyses, respectively.

RESULTS AND CONCLUSIONS

Of the 163, 82 (50.3%) cases had at least one tissue sample that was valid for molecular analysis. Only two of the DNA valid cases (2.4%) were HPV DNA-positive (HPV11 and HPV33). All HPV mRNA assays rendered negative results except for HPV11 transcripts. Results of this study may indicate that there is probably very low prevalence of HPV-associated HNSCC among Filipino adults living in a rural region of the Philippines. This study could serve as a benchmark for designing follow-up studies that would assess possible changes in trends of HNSCC among Filipinos in different ethnic regions of the country, especially urban areas in which the population is expected to adapt Western style sexual behavior. A prospective sampling of fresh frozen tissue is also highly recommended to ensure better molecular analyses.

Human Papillomavirus Associated Cancers of the Head and Neck: An Australian Perspective

Human papillomavirus (HPV) associated head and neck squamous cell carcinomas (HNSCCs), have become a serious global health problem. Despite decreases in HPV-negative HNSCCs, the prevalence of HPV-positive HNSCCs has significantly increased. HPV-positive cancers are associated with superior survival outcomes when compared to HPV-negative cancers, which appears likely to be associated with differences in the molecular pathogenesis of the two diseases. While therapies are still problematic, the current HPV vaccine programs hold a promise for the primary prevention of HPV-related HNSCCs and since Australia was the first to introduce a nationwide HPV vaccine program, it is in a unique position to observe the effects of the vaccine on HNSCCs. This review discusses the epidemiological trends associated with HPV in HNSCC, with reference to the differences between HPV-positive and HPV-negative HNSCCs and the prevention potential of HPV vaccines.

Human papillomavirus (HPV) infection in a case-control study of oral squamous cell carcinoma and its increasing trend in northeastern Thailand

Human papillomavirus (HPV) is an independent risk factor for development of oral squamous cell carcinoma (OSCC). This study aimed to investigate the role of HPV infection and the trend in percentage of HPV-associated OSCC over a 5-year period in northeastern Thailand. In this case-control study, 91 exfoliated oral cell samples and 80 lesion cell samples from OSCC cases and exfoliated oral cells from 100 age/gender-matched controls were collected. HPV infection was investigated by PCR using GP5+/GP6+ primers followed by HPV genotyping using reverse line blot hybridization. Quantitative RT-PCR was used to evaluate HPV oncogene transcription. Temporal trends of HPV infection were evaluated in archived formalin-fixed paraffin-embedded (FFPE) OSCC tissues using in situ hybridization. HPV DNA was found in 17.5% (14/80) of lesion samples from OSCC cases and 29.7% (27/91) of exfoliated oral cell samples from the same cases. These values were significantly higher than in exfoliated oral cell samples from controls (13%, 13/100). HPV-16 was the genotype most frequently found in OSCC cases (92.8%, 13/14 infected cases). Interestingly, HPV oncogene mRNA expression was detected and correlated with OSCC cases (P < 0.005). Of 146 archived FFPE OSCC samples, 82 (56.2%) were positive for high-risk HPV DNA and 64 (43.8%) cases were positive for HPV E6/E7 mRNA expression. There was a trend of increasing percentage of HPV-associated OSCC from 2005 to 2010. This was especially so for females with well-differentiated tumors in specific tongue sub-sites. We suggest that HPV infection plays an important role in oral carcinogenesis in northeastern Thailand.

Prevalence of HPV Infection in Racial-Ethnic Subgroups of Head and Neck Cancer Patients

The landscape of HPV infection in racial/ethnic subgroups of head and neck cancer (HNC) patients has not been evaluated carefully. In this study, a meta-analysis examined the prevalence of HPV in HNC patients of African ancestry. Additionally, a pooled analysis of subject-level data was also performed to investigate HPV prevalence and patterns of p16 (CDNK2A) expression amongst different racial groups. Eighteen publications (N = 798 Black HNC patients) were examined in the meta-analysis, and the pooled analysis included 29 datasets comprised of 3,129 HNC patients of diverse racial/ethnic background. The meta-analysis revealed that the prevalence of HPV16 was higher among Blacks with oropharyngeal cancer than Blacks with non-oropharyngeal cancer. However, there was great heterogeneity observed among studies (Q test P<0.0001). In the pooled analysis, after adjusting for each study, year of diagnosis, age, gender and smoking status, the prevalence of HPV16/18 in oropharyngeal cancer patients was highest in Whites (61.1%), followed by 58.0% in Blacks and 25.2% in Asians (P<0.0001). There was no statistically significant difference in HPV16/18 prevalence in non-oropharyngeal cancer by race (P=0.682). With regard to the pattern of HPV16/18 status and p16 expression, White patients had the highest proportion of HPV16/18+/p16+ oropharyngeal cancer (52.3%), while Asians and Blacks had significantly lower proportions (23.0% and 22.6%, respectively) [P <0.0001]. Our findings suggest that the pattern of HPV16/18 status and p16 expression in oropharyngeal cancer appears to differ by race and this may contribute to survival disparities.

Branchiogenic carcinoma with high-risk-type human papillomavirus infection: A case report

Branchiogenic carcinoma (BC) usually appears as a mass lesion with a predominant cystic component. Since lymph node metastasis from oropharyngeal carcinoma (OPC) has a cystic appearance, it is occasionally difficult to distinguish between BC and nodal metastases from clinically silent OPC. Factors associated with the malignant transformation process in BC remain obscure. The present study reports the case of a 56-year-old man with a right cystic cervical mass that was diagnosed as squamous cell carcinoma based on examination by fine-needle aspiration biopsy. The primary tumor could not be detected despite several imaging examinations, a pan-endoscopy of the head and neck, esophagus and stomach, biopsies of the head and neck regions, and bilateral tonsillectomies. The pathological findings of the surgical specimens from a radical neck dissection were consistent with the histological characteristics of BC, with evidence of transition from dysplasia through intraepithelial carcinoma to invasive carcinoma. Normal squamous epithelium and dysplastic and cancerous portions in the BC showed strong p16^INK4a immunoreactivity. The expression of p16^INK4a was also observed in all 9 nodal metastases in the neck dissection specimens. The cystic formation observed in the BC was not observed in the nodal metastases. As the presence of human papillomavirus-16 in the tumor was confirmed by polymerase chain reaction, quantitative polymerase chain reaction was employed for the measurement of human papillomavirus-16 viral load and integration. The results showed that the viral load of human papillomavirus-16 was 3.01×10⁷/50 ng genomic DNA, and the E2/E6 ratio was 0.13, so the integration state was judged to be the mixed type. To the best of our knowledge, this is the first report of BC associated with high-risk-type human papillomavirus infection. The study indicates that a human papillomavirus-positive neck mass may not necessarily be OPC, but that it could be BC with a poor prognosis. This report lends support to the existence of BC and proposes that the etiology is human papillomavirus infection.

Risk Factors for Oral Human Papillomavirus Infection in Healthy Individuals: A Systematic Review and Meta-Analysis

BACKGROUND

Oral human papillomavirus (HPV) infection is associated with oral cancer development. However, few epidemiologic investigations have focused on oral HPV prevalence in healthy individuals. The objective of this study was to provide updated information regarding oral HPV prevalence in patients without oral cancer worldwide.

METHODS

We systematically reviewed 29 studies reporting the prevalence of oral HPV infection that included 22,756 subjects (10,124 males, 12,623 females, and nine unknown gender; age range 2 - 89 years) and were published from January 2012 to June 2015.

RESULTS

The prevalence of overall HPV, low-risk type HPV, high-risk type HPV, and HPV16 in the reported cases was 5.5%, 2.2%, 2.7%, and 1.0%, respectively. The prevalence of overall HPV was considerably higher in males who had sex with males (12.2%) as compared to heterosexual males (4.7%) and females (2.9%). A meta-analysis was performed to elucidate significant risk factors for oral HPV infection, which revealed a significant statistical association for oral sex and smoking with oral HPV infection (odds ratio (OR): 1.90, 95% confidence interval (CI): 1.51 - 2.39, P < 0.0001; OR: 2.13, 95% CI: 1.32 - 3.43, P = 0.002).

CONCLUSIONS

Our findings suggest that sexual behavior and smoking are importantly related to oral HPV infection in healthy individuals.

Infectious Agents Associated with Head and Neck Carcinomas

In addition to traditional risk factors such as smoking habits and alcohol consumption, certain microbes also play an important role in the generation of head and neck carcinomas. Infection with high-risk human papillomavirus types is strongly associated with the development of oropharyngeal carcinoma, and Epstein-Barr virus appears to be indispensable for the development of non-keratinizing squamous cell carcinoma of the nasopharynx. Other viruses including torque teno virus and hepatitis C virus may act as co-carcinogens, increasing the risk of malignant transformation. A shift in the composition of the oral microbiome was associated with the development of oral squamous cell carcinoma, although the causal or casual role of oral bacteria remains to be clarified. Conversion of ethanol to acetaldehyde, a mutagenic compound, by members of the oral microflora as well as by fungi including Candida albicans and others is a potential mechanism that may increase oral cancer risk. In addition, distinct Candida spp. also produce NBMA (N-nitrosobenzylmethylamine), a potent carcinogen. Inflammatory processes elicited by microbes may also facilitate tumorigenesis in the head and neck region.

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.

Human Papillomavirus Laboratory Testing: the Changing Paradigm

High-risk human papillomaviruses (HPVs) cause essentially all cervical cancers, most anal and oropharyngeal cancers, and some vaginal, vulvar, and penile cancers. Improved understanding of the pathogenesis of infection and the availability of newer tests are changing the approach to screening and diagnosis. Molecular tests to detect DNA from the most common high-risk HPVs are FDA approved for use in conjunction with cytology in cervical cancer screening programs. More-specific tests that detect RNA from high-risk HPV types are now also available. The use of molecular tests as the primary screening tests is being adopted in some areas. Genotyping to identify HPV16 and -18 has a recommended role in triaging patients for colposcopy who are high-risk HPV positive but have normal cytology. There are currently no recommended screening methods for anal, vulvar, vaginal, penile, or oropharyngeal HPV infections. HPV testing has limited utility in patients at high risk for anal cancer, but p16 immunohistochemistry is recommended to clarify lesions in tissue biopsy specimens that show moderate dysplasia or precancer mimics. HPV testing is recommended for oropharyngeal squamous cell tumors as a prognostic indicator. Ongoing research will help to improve the content of future guidelines for screening and diagnostic testing.

A pilot study to compare the detection of HPV-16 biomarkers in salivary oral rinses with tumour p16(INK4a) expression in head and neck squamous cell carcinoma patients

Background

Human papilloma virus-16 (HPV-16) infection is a major risk factor for a subset of head and neck squamous cell carcinoma (HNSCC), in particular oropharyngeal squamous cell carcinoma (OPSCC). Current techniques for assessing the HPV-16 status in HNSCC include the detection of HPV-16 DNA and p16^INK4a expression in tumor tissues. When tumors originate from hidden anatomical sites, this method can be challenging. A non-invasive and cost-effective alternative to biopsy is therefore desirable for HPV-16 detection especially within a community setting to screen at-risk individuals.

Methods

The present study compared detection of HPV-16 DNA and RNA in salivary oral rinses with tumor p16^INK4a status, in 82 HNSCC patients using end-point and quantitative polymerase chain reaction (PCR).

Results

Of 42 patients with p16^INK4a-positive tumours, 39 (sensitivity = 92.9 %, PPV = 100 % and NPV = 93 %) had oral rinse samples with detectable HPV-16 DNA, using end-point and quantitative PCR. No HPV-16 DNA was detected in oral rinse samples from 40 patients with p16^INK4a negative tumours, yielding a test specificity of 100 %. For patients with p16^INK4a positive tumours, HPV-16 mRNA was detected using end-point reverse transcription PCR (RT-PCR) in 24/40 (sensitivity = 60 %, PPV = 100 % and NPV = 71 %), and using quantitative RT-PCR in 22/40 (sensitivity = 55 %, PPV = 100 % and NPV = 69 %). No HPV-16 mRNA was detected in oral rinse samples from the p16^INK4a-negative patients, yielding a specificity of 100 %.

Conclusions

We demonstrate that the detection of HPV-16 DNA in salivary oral rinse is indicative of HPV status in HNSCC patients and can potentially be used as a diagnostic tool in addition to the current methods.

Electronic supplementary material

The online version of this article (doi:10.1186/s12885-016-2217-1) contains supplementary material, which is available to authorized users.

Effects of Methylation Status of CpG Sites within the HPV16 Long Control Region on HPV16-Positive Head and Neck Cancer Cells

Objective

To map comprehensively the methylation status of the CpG sites within the HPV16 long control region (LCR) in HPV-positive cancer cells, and to explore further the effects of methylation status of HPV16 LCR on cell bioactivity and E6 and E7 expression. In addition, to analyze the methylation status of the LCR in HPV-positive oropharyngeal squamous cell carcinoma (OPSCC) patients.

Methods and Materials

Methylation patterns of HPV16 LCR in UM-SCC47, CaSki, and SiHa cells and HPV16-positiive OPSCC specimens were detected by bisulfite-sequencing PCR and TA cloning. For cells treated with 5-aza-2′-deoxycytidine and E6 and E7 knockdown, MTS and trypan blue staining, annexin-V and 7-AAD staining, and prodidium iodide were used to evaluate cell growth and cell proliferation, cell apoptosis, and cell cycle arrest, respectively. E6 and E7 mRNA and protein expression were analyzed by quantitative real-time PCR and immunocytochemistry, respectively.

Results

Hypermethylation status of the LCR in UM-SCC47 (79.8%) and CaSki cells (90.0%) and unmethylation status of the LCR in SiHa cells (0%) were observed. Upon demethylation, the cells with different methylation levels responded differently during growth, apoptosis, and cell cycle arrest, as well as in terms of their E6 and E7 expression. In HPV16-positive OPSCC patients, the methylation rates were 9.5% in the entire LCR region, 13.9% in the 5′-LCR, 6.0% in the E6 enhancer, and 9.5% in the p97 promoter, and hypermethylation of p97 promoter was found in a subset of cases (20.0%, 2/10).

Conclusions

Our study revealed two different methylation levels of the LCR in HPV16-positive cancer cells and OPSCC patients, which may represent different carcinogenesis mechanisms of HPV-positive cancers cells. Demethylating the meCpGs in HPV16 LCR might be a potential target for a subgroup of HPV16-positive patients with head and neck squamous cell carcinoma.