Genomic profiling identifies common HPV-associated chromosomal alterations in squamous cell carcinomas of cervix and head and neck

Prognostic Markers and Driver Genes and Options for Targeted Therapy in Human-Papillomavirus-Positive Tonsillar and Base-of-Tongue Squamous Cell Carcinoma

The incidence of Human-papillomavirus-positive (HPV⁺) tonsillar and base-of-tongue squamous cell carcinoma (TSCC and BOTSCC, respectively) is increasing epidemically, but they have better prognosis than equivalent HPV-negative (HPV⁻) cancers, with roughly 80% vs. 50% 3-year disease-free survival, respectively. The majority of HPV⁺ TSCC and BOTSCC patients therefore most likely do not require the intensified chemoradiotherapy given today to head and neck cancer patients and would with de-escalated therapy avoid several severe side effects. Moreover, for those with poor prognosis, survival has not improved, so better-tailored alternatives are urgently needed. In line with refined personalized medicine, recent studies have focused on identifying predictive markers and driver cancer genes useful for better stratifying patient treatment as well as for targeted therapy. This review presents some of these endeavors and briefly describes some recent experimental progress and some clinical trials with targeted therapy.

A census of pathway maps in cancer systems biology

A key goal of cancer systems biology is to use big data to elucidate the molecular networks by which cancer develops. However, to date there has been no systematic evaluation of how far these efforts have progressed. In this Analysis, we survey six major systems biology approaches for mapping and modelling cancer pathways with attention to how well their resulting network maps cover and enhance current knowledge. Our sample of 2,070 systems biology maps captures all literature-curated cancer pathways with significant enrichment, although the strong tendency is for these maps to recover isolated mechanisms rather than entire integrated processes. Systems biology maps also identify previously underappreciated functions, such as a potential role for human papillomavirus-induced chromosomal alterations in ovarian tumorigenesis, and they add new genes to known cancer pathways, such as those related to metabolism, Hippo signalling and immunity. Notably, we find that many cancer networks have been provided only in journal figures and not for programmatic access, underscoring the need to deposit network maps in community databases to ensure they can be readily accessed. Finally, few of these findings have yet been clinically translated, leaving ample opportunity for future translational studies. Periodic surveys of cancer pathway maps, such as the one reported here, are critical to assess progress in the field and identify underserved areas of methodology and cancer biology.

New serum biomarker identification and analysis by mass spectrometry in cervical precancerous lesion and acute cervicitis in South China

Background: According to the statistics of WHO/IARC, cervical cancer (CC) has become the fourth malignant cancer of female worldwide and it is one of the main causes of death of women in developing countries.

Purpose: Potential plasma and metabolic biomarkers for CC precancerous lesions and cervicitis were indicated by LC-MS techniques, and their underlying mechanisms and functions were analyzed.

Methods: Plasma samples were selected from healthy people (control), low-grade squamous intraepithelial lesions (LSIL), high-grade squamous intraepithelial lesions (HSIL), CC, and post-treatment patients. All polypeptide types and sequences were detected by LC-MS/MS and the results were normalized by using Pareto-scaling. Potential metabolic biomarkers were screened by applying MetaboAnalyst 4.0 software and XCMS software, and analysis of variance and enrichment analysis were performed. Metabolic pathway analysis and functional enrichment analysis were used to further investigate the significance and pathological mechanisms of potential biomarkers.

Results: Compared with healthy people, 9 differentially expressed metabolites were screened, 4 of which were up-regulated and 5 were down-regulated. LSIL group screened 7 differentially expressed metabolites, 5 of which were up-regulated and 2 were down-regulated; CC group screened 12 differentially expressed metabolites were screened, of which 9 were up-regulated and 3 were down-regulated. Eight differentially expressed metabolites were screened in the IF group, of which 5 showed up-regulation and 3 showed down-regulation. In functional enrichment analysis, differential metabolism was found to be associated with addition and coagulation cascades. Among all potential biomarkers, 2-amino-3-methyl-1-butanol, L-carnitine, Asn Asn Gln Arg, Ala Cys Ser Trp, Soladulcidine, Ala Ile Gln Arg, 2-amino-3 -Methyl-1-butanol, L-carnitine, Asn Asn Gln Arg, Ala Cys Ser Trp, Soladulcidine, Ala Ile Gln Arg can be used as predictors of precancerous lesions at different stages of CC. Among all biomarkers, 6α-fluoro-11β1,17-dihydroxypren-4-ene-3,20-dione has higher expression in the CC and HSIL groups and lower expression in the treatment group.

Conclusion: By applying molecular markers to assess the progression of the disease, the accuracy and specificity of the diagnosis can be improved, which has certain prospects in clinical applications.

The Double-Edged Sword-How Human Papillomaviruses Interact With Immunity in Head and Neck Cancer

Patients with human papilloma virus (HPV)-associated head and neck squamous cell carcinoma (HNSCC) have remarkably better prognosis, which differs from HPV-negative oropharyngeal squamous cell carcinoma (OPSCC) with respect to clinical, genomic, molecular, and immunological aspects, especially having the characteristics of high levels of immune cell infiltration and high degrees of immunosuppression. This review will summarize immune evasion mechanisms in HPV-positive HNSCC, analyze the host various immune responses to HPV and abundant numbers of infiltrating immune cell, and discuss the differences between HPV-positive HNSCC with cervical cancer. A deeper understanding of the immune landscape will help new concepts to emerge in immune-checkpoint oncology, which might be a valuable add-on to established concepts.

Three Prime Repair Exonuclease 1 (TREX1) expression correlates with cervical cancer cells growth in vitro and disease progression in vivo

Alterations in specific DNA damage repair mechanisms in the presence of human papillomavirus (HPV) infection have been described in different experimental models. However, the global effect of HPV on the expression of genes involved in these pathways has not been analyzed in detail. In the present study, we compared the expression profile of 135 genes involved in DNA damage repair among primary human keratinocytes (PHK), HPV-positive (SiHa and HeLa) and HPV-negative (C33A) cervical cancer derived cell lines. We identified 9 genes which expression pattern distinguishes HPV-positive tumor cell lines from C33A. Moreover, we observed that Three Prime Repair Exonuclease 1 (TREX1) expression is upregulated exclusively in HPV-transformed cell lines and PHK expressing HPV16 E6 and E7 oncogenes. We demonstrated that TREX1 silencing greatly affects tumor cells clonogenic and anchorage independent growth potential. We showed that this effect is associated with p53 upregulation, accumulation of subG1 cells, and requires the expression of E7 from high-risk HPV types. Finally, we observed an increase in TREX1 levels in precancerous lesions, squamous carcinomas and adenocarcinomas clinical samples. Altogether, our results indicate that TREX1 upregulation is important for cervical tumor cells growth and may contribute with tumor establishment and progression.

Human papillomavirus and genome instability: from productive infection to cancer

Infection with high oncogenic risk human papillomavirus types is the etiological factor of cervical cancer and a major cause of other epithelial malignancies, including vulvar, vaginal, anal, penile and head and neck carcinomas. These agents affect epithelial homeostasis through the expression of specific proteins that deregulate important cellular signaling pathways to achieve efficient viral replication. Among the major targets of viral proteins are components of the DNA damage detection and repair machinery. The activation of many of these cellular factors is critical to process viral genome replication intermediates and, consequently, to sustain faithful viral progeny production. In addition to the important role of cellular DNA repair machinery in the infective human papillomavirus cycle, alterations in the expression and activity of many of its components are observed in human papillomavirus-related tumors. Several studies from different laboratories have reported the impact of the expression of human papillomavirus oncogenes, mainly E6 and E7, on proteins in almost all the main cellular DNA repair mechanisms. This has direct consequences on cellular transformation since it causes the accumulation of point mutations, insertions and deletions of short nucleotide stretches, as well as numerical and structural chromosomal alterations characteristic of tumor cells. On the other hand, it is clear that human papillomavirus-transformed cells depend on the preservation of a basal cellular DNA repair activity level to maintain tumor cell viability. In this review, we summarize the data concerning the effect of human papillomavirus infection on DNA repair mechanisms. In addition, we discuss the potential of exploiting human papillomavirus-transformed cell dependency on DNA repair pathways as effective antitumoral therapies.

Molecular heterogeneity in human papillomavirus-dependent and -independent vulvar carcinogenesis

Vulvar squamous cell carcinoma (VSCC) and precancerous vulvar intraepithelial neoplasia (VIN) can develop through human papillomavirus (HPV)-dependent and -independent pathways, indicating a heterogeneous disease. Only a minority of VIN progress, but current clinicopathological classifications are insufficient to predict the cancer risk. Here we analyzed copy number alterations (CNA) to assess the molecular heterogeneity of vulvar lesions in relation to HPV and cancer risk. HPV-status and CNA by means of whole-genome next-generation shallow-sequencing were assessed in VSCC and VIN. The latter included VIN of women with associated VSCC (VINVSCC ) and women who did not develop VSCC during follow-up (VINnoVSCC ). HPV-testing resulted in 41 HPV-positive (16 VINVSCC , 14 VINnoVSCC , and 11 VSCC) and 24 HPV-negative (11 VINVSCC and 13 VSCC) lesions. HPV-positive and -negative VSCC showed a partially overlapping pattern of recurrent CNA, including frequent gains of 3q and 8q. In contrast, amplification of 11q13/cyclinD1 was exclusively found in HPV-negative lesions. HPV-negative VINVSCC had less CNA than HPV-negative VSCC (P = .009), but shared chromosome 8 alterations. HPV-positive VINnoVSCC had less CNA than VINVSCC (P = .022). Interestingly, 1pq gain was detected in 81% of HPV-positive VINVSCC and only in 21% of VINnoVSCC (P = .001). In conclusion, HPV-dependent and -independent vulvar carcinogenesis is characterized by distinct CNA patterns at the VIN stage, while more comparable patterns are present at the cancer stage. Cancer risk in VIN seems to be reflected by the extent of CNA, in particular chromosome 1 gain in HPV-positive cases.

Molecular mechanisms of the preventable causes of cancer in the United States

Annually, there are 1.6 million new cases of cancer and nearly 600,000 cancer deaths in the United States alone. The public health burden associated with these numbers has motivated enormous research efforts into understanding the root causes of cancer. These efforts have led to the recognition that between 40% and 45% of cancers are associated with preventable risk factors and, importantly, have identified specific molecular mechanisms by which these exposures modify human physiology to induce or promote cancer. The increasingly refined knowledge of these mechanisms, which we summarize here, emphasizes the need for greater efforts toward primary cancer prevention through mitigation of modifiable risk factors. It also suggests exploitable avenues for improved secondary prevention (which includes the development of therapeutics designed for cancer interception and enhanced techniques for noninvasive screening and early detection) based on detailed knowledge of early neoplastic pathobiology. Such efforts would complement the current emphasis on the development of therapeutic approaches to treat established cancers and are likely to result in far greater gains in reducing morbidity and mortality.

Prognostic role of PIK3CA and TP53 in human papillomavirus-negative oropharyngeal cancers

BACKGROUND

Human papilloma virus (HPV)-negative oropharyngeal squamous cell carcinomas (OPCs) have a poorer prognosis and best management is an unmet need. We studied the prognostic role of epidermal growth factor receptor (EGFR) and PIK3CA amplifications and TP53 functional status.

METHODS

Between 1992 and 2000, 90 consecutive patients with OPCs were treated with surgery, followed by radiotherapy in case of high-risk pathologic features. Of those, 73 cases were HPV-negative and therefore were selected for molecular analysis ( PIK3CA and EGFR fluorescent in situ hybridization [FISH] analysis and TP53 mutation analysis).

RESULTS

FISH analyses of EGFR and PIK3CA were successfully conducted on 69 and 63 of 73 tumor samples, respectively. EGFR alterations were detected in 43% of patients but just 7% showed amplification. Seven cases (11%) carried PIK3CA amplification and 18 (29%) gene gain or high polysomy. TP53 was detected as nonfunctional in 24 of 67 (36%) successfully analyzed cases. Both univariable and multivariable analysis showed statistically significantly worse disease-free survival (DFS) for patients with PIK3CA disomy compared to those with gene gain or high polysomy. No differences in overall survival or DFS for EGFR and TP53 alteration were evident. The combined evaluation of PIK3CA and TP53 showed that PIK3CA gene copy number gain separated a population with better outcome, defining an overall worse prognosis population (disomy) now clearly further divided according to TP53 functional status.

CONCLUSION

PIK3CA gene copy number increase is associated with a favorable clinical outcome in HPV-negative OPCs treated with surgery ± postoperative radiotherapy. In patients without PIK3CA alteration, TP53 nonfunctional mutations are associated with poor prognosis.

Human papilloma virus: Apprehending the link with carcinogenesis and unveiling new research avenues (Review)

Human papilloma viruses (HPV) are a small group of non‑enveloped viruses belonging to the Papillomaviridae family with strong similarities to polyoma viruses. The viral particles consist of a genome in the form of a circular double‑stranded DNA, encompassing eight open reading frames, as well as a non‑enveloped icosahedral capsid. HPV infection is considered the most common sexually transmitted disease in both sexes and is strongly implicated in the pathogenesis of different types of cancer. 'High‑risk' mucosal HPV types, predominantly types 16, 18, 31, 33 and 35, are associated with most cervical, penile, vulvar, vaginal, anal, oropharyngeal cancers and pre‑cancers. Screening for HPV is necessary for the prognosis and for determining treatment strategies for cancer. Novel HPV markers, including proteomic and genomic markers, as well as anti‑papillomavirus vaccines are currently available. The aim of this comprehensive review was to thoroughly present the updated information on virus development, cancer occurrence, treatment and prevention strategies, in an attempt to shed further light into the field, including novel research avenues.

Next generation sequencing and its applications in HPV-associated cancers

Approximately 18% of all human cancers have a viral etiology, and human papillomavirus (HPV) has been identified as one of the most prevalent viruses that plays causative role in nearly all cervical cancers and, in addition, in subset of head and neck, anal, penile and vulvar cancers. The recent introduction of next generation sequencing (NGS) and other omics approaches have resulted in comprehensive knowledge on the pathogenesis of HPV-driven tumors. Specifically, these approaches have provided detailed information on genomic HPV integration sites, disrupted genes and pathways, and common and distinct genetic and epigenetic alterations in different human HPV-associated cancers. This review focuses on HPV integration sites, its concomitantly disrupted genes and pathways and its functional consequences in both cervical and head and neck cancers. Integration of NGS data with other omics and clinical data is crucial to better understand the pathophysiology of each individual malignancy and, based on this, to select targets and to design effective personalized treatment options.

Proteomics approaches in cervical cancer: focus on the discovery of biomarkers for diagnosis and drug treatment monitoring

INTRODUCTION

The HPV virus accounts for the majority of cervical cancer cases. Although a diagnostic tool (Pap Test) is widely available, cervical cancer incidence still remains high worldwide, and especially in developing countries, attributed to a large extent to suboptimal sensitivities of the Pap test and unavailability of the test in developing countries.

AREAS COVERED

Proteomics approaches have been used in order to understand the HPV virus correlation to cervical cancer pathology, as well as to discover putative biomarkers for early cervical cancer diagnosis and drug mode of action. Expert commentary: The present review summarizes the latest in vitro and in vivo proteomic studies for the discovery of putative cervical cancer biomarkers and the evaluation of available drugs and treatments.

Predictive Factors for Outcome and Quality of Life in HPV-Positive and HPV-Negative HNSCC

Infection with high-risk types of the human papilloma virus (HPV) is an etiological risk factor for oropharyngeal squamous cell carcinoma (OPSCC) and associated with a better response to therapy and improved survival. A better understanding of the molecular principles underlying the differences in clinical behavior could pave the way to establish more effective and less toxic therapy for HPV-positive OPSCC and their HPV-negative counterparts. Compelling experimental evidence demonstrates that extensive global reprogramming of epigenetic profiles is as important as genetic mutations during neoplastic transformation and malignant progression, including HPV-positive OPSCC. In this chapter, the current knowledge on HPV-related alterations in DNA methylation, histone modification, and chromosome remodeling will be summarized and assessment of cancer-related profiles will be discussed as a valuable tool to gain important diagnostic or prognostic information for therapeutic decision-making and clinical management of HNSCC patients.

Robust Differences in p16-Dependent Oropharyngeal Squamous Cell Carcinoma Distant Metastasis

Objective

Historically, head and neck squamous cell carcinoma (HNSCC) has been earmarked a lymphatic malignancy. Recently, this has been called into question. Our study aims to (1) illustrate the robust differences in distant metastases between p16+ and p16– oropharyngeal squamous cell carcinoma (OPSCC) and (2) provide support that p16+ OPSCC has a predilection toward vasculature invasion and hematogenous spread.

Study Design

Multi-institutional, case series with chart review.

Setting

Four academic institutions.

Subjects and Methods

Within a group of 1113 patients with primary OPSCC who received treatment between 1979 and 2013, those who developed distant metastasis (DM) were divided into 2 cohorts based on p16 status. Intergroup and intragroup univariate analysis was performed as well as descriptive analysis of end-organ sites.

Results

Of the 1058 patients included, 89 developed DM. Thirty were p16– and 59 were p16+. Of the p16– patients with DM, only 10% had disseminated disease (distant metastases at ≥2 sites) compared with 74% of p16+ patients. Distant disease in p16+ patients included brain, abdomen, and a distinct pattern of pulmonary metastases.

Conclusion

Our large, multi-institutional study supports published reports that p16+ OPSCC metastasizes with a unique phenotype that is hematogenous and widely disseminated with atypical end-organ sites. Our data suggest that p16+ OPSCC has a predilection toward active vasculature invasion as evidenced by the results and illustrative radiologic and pathohistologic examples. These findings may have implications for future targeted therapy when treating p16+ OPSCC.

Genomic landscape of human papillomavirus-associated cancers

Recent next-generation sequencing studies have generated a comprehensive overview of the genomic landscape of human papillomavirus (HPV)-associated cancers. This review summarizes these findings to provide insight into the tumor biology of these cancers and potential therapeutic opportunities for HPV-driven malignancies. In addition to the tumorigenic properties of the HPV oncoproteins, integration of HPV DNA into the host genome is suggested to be a driver of the neoplastic process. Integration may confer a growth and survival advantage via enhanced expression of viral oncoproteins, alteration of critical cellular genes, and changes in global promoter methylation and transcription. Alteration of cellular genes may lead to loss of function of tumor suppressor genes, enhanced oncogene expression, loss of function of DNA repair genes, or other vital cellular functions. Recurrent integrations in RAD51B, NR4A2, and TP63, leading to aberrant forms of these proteins, are observed in both HPV-positive head and neck squamous cell carcinoma (HNSCC) and cervical carcinoma. Additional genomic alterations, independent of integration events, include recurrent PIK3CA mutations (and aberrations in other members of the PI3K pathway), alterations in receptor tyrosine kinases (primarily FGFR2 and FGFR3 in HPV-positive HNSCC, and ERBB2 in cervical squamous cell carcinoma), and genes in pathways related to squamous cell differentiation and immune responses. A number of the alterations identified are potentially targetable, which may lead to advances in the treatment of HPV-associated cancers.

Predictive value of epigenetic alterations in head and neck squamous cell carcinoma

Head and neck cancer collectively describes malignant tumors originating from the mucosal surface of the upper aerodigestive tract. These tumors pose a great threat to public health because of their high incidence and mortality. Traditional risk factors are tobacco and alcohol abuse. More recently, infection by high-risk types of human papilloma virus (HPV) has been identified as an additional risk factor, especially for oropharyngeal squamous cell carcinoma (OPSCC). Moreover, HPV-positive OPSCC is considered a distinct tumor entity with an improved clinical outcome compared to HPV-negative OPSCC. Epigenetic alterations act as key events in the pathogenesis of cancer and are of special interest for basic and translational oncology because of their reversible nature. This review provides a comprehensive summary of alterations of the epigenome in head and neck squamous cell carcinoma (HNSCC) with a focus on the methylome (hypomethylation and hypermethylation) and its predictive value in the evaluation of pathologic states and clinical outcome, or monitoring response rates to certain therapies.

Human papillomavirus induced transformation in cervical and head and neck cancers

Human papillomavirus (HPV) is one of the most widely publicized and researched pathogenic DNA viruses. For decades, HPV research has focused on transforming viral activities in cervical cancer. During the past 15 years, however, HPV has also emerged as a major etiological agent in cancers of the head and neck, in particular squamous cell carcinoma. Even with significant strides achieved towards the screening and treatment of cervical cancer, and preventive vaccines, cervical cancer remains the leading cause of cancer-associated deaths for women in developing countries. Furthermore, routine screens are not available for those at risk of head and neck cancer. The current expectation is that HPV vaccination will prevent not only cervical, but also head and neck cancers. In order to determine if previous cervical cancer models for HPV infection and transformation are directly applicable to head and neck cancer, clinical and molecular disease aspects must be carefully compared. In this review, we briefly discuss the cervical and head and neck cancer literature to highlight clinical and genomic commonalities. Differences in prognosis, staging and treatment, as well as comparisons of mutational profiles, viral integration patterns, and alterations in gene expression will be addressed.

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

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

Reverse-phase protein array profiling of oropharyngeal cancer and significance of PIK3CA mutations in HPV-associated head and neck cancer

PURPOSE

Human papilloma virus (HPV)-associated (HPV+) oropharyngeal squamous cell carcinomas (OPSCC) have different molecular and biologic characteristics and clinical behavior compared with HPV-negative (HPV-) OPSCC. PIK3CA mutations are more common in HPV(+) OPSCC. To define molecular differences and tumor subsets, protein expression and phosphorylation were compared between HPV(+) and HPV(-) OPSCC and between tumors with and without PIK3CA mutations.

EXPERIMENTAL DESIGN

Expression of 137 total and phosphorylated proteins was evaluated by reverse-phase protein array in 29 HPV(+) and 13 HPV(-) prospectively collected OPSCCs. Forty-seven OPSCCs were tested for hotspot-activating mutations in PIK3CA and AKT. Activation of PIK3CA downstream targets and sensitivity to pathway inhibitors were determined in HPV(+) head and neck cancer cells overexpressing wild-type or mutant PIK3CA.

RESULTS

Analyses revealed 41 differentially expressed proteins between HPV(+) and HPV(-) OPSCC categorized into functional groups: DNA repair, cell cycle, apoptosis, phosphoinositide 3-kinase (PI3K)/AKT/mTOR, and receptor kinase pathways. All queried DNA repair proteins were significantly upregulated in HPV(+) samples. A total of 8 of 33 HPV(+) and 0 of 14 HPV(-) tumors contained activating PIK3CA mutations. Despite all activating PIK3CA mutations occurring in HPV(+) samples, HPV(+) tumors had lower mean levels of activated AKT and downstream AKT target phosphorylation. Ectopic expression of mutant PIK3CA in HPV(+) cells increased mTOR, but not AKT activity. HPV E6/E7 overexpression inhibited AKT phosphorylation in HPV-negative cells. Mutant PIK3CA overexpressing cells were more sensitive to a dual PI3K/mTOR inhibitor compared with an AKT inhibitor.

CONCLUSIONS

Protein expression analyses suggest that HPV(+) and HPV(-) OPSCC differentially activate DNA repair, cell cycle, apoptosis, PI3K/AKT/mTOR, and receptor kinase pathways. PIK3CA mutations are more common in HPV(+) OPSCC and are associated with activation of mTOR, but not AKT. These data suggest that inhibitors for mTOR may have activity against HPV(+) PIK3CA mutant oropharyngeal cancers.

Genome stability pathways in head and neck cancers

Genomic instability underlies the transformation of host cells toward malignancy, promotes development of invasion and metastasis and shapes the response of established cancer to treatment. In this review, we discuss recent advances in our understanding of genomic stability in squamous cell carcinoma of the head and neck (HNSCC), with an emphasis on DNA repair pathways. HNSCC is characterized by distinct profiles in genome stability between similarly staged cancers that are reflected in risk, treatment response and outcomes. Defective DNA repair generates chromosomal derangement that can cause subsequent alterations in gene expression, and is a hallmark of progression toward carcinoma. Variable functionality of an increasing spectrum of repair gene polymorphisms is associated with increased cancer risk, while aetiological factors such as human papillomavirus, tobacco and alcohol induce significantly different behaviour in induced malignancy, underpinned by differences in genomic stability. Targeted inhibition of signalling receptors has proven to be a clinically-validated therapy, and protein expression of other DNA repair and signalling molecules associated with cancer behaviour could potentially provide a more refined clinical model for prognosis and treatment prediction. Development and expansion of current genomic stability models is furthering our understanding of HNSCC pathophysiology and uncovering new, promising treatment strategies.

Chromosomal gains and losses in human papillomavirus-associated neoplasia of the lower genital tract - a systematic review and meta-analysis

BACKGROUND

Overexpression of the human papillomavirus (HPV) oncogenes E6 and E7 is necessary for the development of distinct lower genital tract cancers. However, secondary cellular genomic alterations are mandatory to promote progression of HPV-induced premalignant stages. We aimed at identifying the chromosomal regions most frequently gained and lost and the disease stage at which the latter occurs. These regions might be relevant for carcinogenesis and could serve as diagnostic markers to identify premalignant lesions with high progression risk towards invasive cancer.

METHODS

We performed a systematic literature review and meta-analysis of studies listed in PubMed that analysed chromosomal copy number alterations by comparative genomic hybridisation (CGH) in HPV-positive and -negative cancers or premalignant lesions of the anogenital tract (cervix, anus, vagina, penis and vulva).

FINDINGS

Data were extracted and analysed from 32 studies. The most common alterations in cervical squamous cell carcinoma (SCC) (12 studies, 293 samples) were gains at 3q with a rate of 0.55 (95% confidence interval (CI) 0.43-0.70), losses at 3p (0.36, 95%CI 0.27-0.48) and losses at 11q (0.33, 95%CI 0.26-0.43). Gains at 3q were particularly frequent in HPV16-positive cervical SCC (0.84, 95%CI 0.78-0.90). Also more than one quarter of high grade cervical intraepithelial neoplasia (CIN) harboured gains of 3q (0.27, 95%CI 0.20-0.36), but the rate in low grade CIN was low (0.02, 95%CI 0.00-0.09). For HPV-associated vulvar SCC (four studies, 30 samples) the same common alterations as in cervical SCC were reported. Studies on non-cervical and non-vulvar SCC and premalignant lesions of the lower genital tract are scarce.

INTERPRETATION

3q gains were most frequently found in HPV16-positive cervical SCC. The results suggest the selection of HPV-transformed cell clones harbouring 3q gains in high grade premalignant lesions, while alterations in low grade lesions are rare.

The interplay between HPV and host immunity in head and neck squamous cell carcinoma

Persistent infection with human papillomavirus (HPV) type 16 is a major risk factor for the development of head and neck squamous cell carcinoma (HNSCC), in particular oropharyngeal squamous cell carcinoma (OPSCC). The oropharyngeal epithelium differs from the mucosal epithelium at other commonly HPV16-infected sites (i.e., cervix and anogenital region) in that it is juxtaposed with the underlying lymphatic tissue, serving a key immunologic function in the surveillance of inhaled and ingested pathogens. Therefore, the natural history of infection and immune response to HPV at this site may differ from that at other anatomic locations. This review summarizes the literature concerning the adaptive immune response against HPV in the context of HNSCC, with a focus on the T-cell response. Recent studies have shown that a broad repertoire of tumor-infiltrating HPV-specific T-cells are found in nearly all patients with HPV-positive tumors. A systemic response is found in only a proportion of these. Furthermore, the local response is more frequent in OPSCC patients than in cervical cancer patients and HPV-negative OPSCC patients. Despite this, tumor persistence may be facilitated by abnormalities in antigen processing, a skewed T-helper cell response, and an increased local prevalence of T-regulatory cells. Nonetheless, the immunologic profile of HPV-positive vs. HPV-negative HNSCC is associated with a significantly better outcome, and the HPV-specific immune response is suggested to play a role in the significantly better response to therapy of HPV-positive patients. Immunoprofiling may prove a valuable prognostic tool, and immunotherapy trials targeting HPV are underway, providing hope for decreasing treatment-related toxicity.

Eurogin Roadmap: comparative epidemiology of HPV infection and associated cancers of the head and neck and cervix

The EUROGIN 2012 roadmap is focused on the comparative epidemiology of human papillomavirus (HPV) associated head and neck squamous cell cancers (HNSCC) and cervical cancers. Discussed are the similarities and differences between the two cancers with regard to global disease burden, HPV prevalence and type distribution, disease cofactors, molecular pathogenesis, treatment approaches, prognostic factors and primary and secondary prevention. The global incidence of HNSCC and cervical cancer is similar; however, a minority of HNSCC in comparison to virtually all cervical cancers is caused by HPV. HPV infection prevalence is considerably lower in the oral than genital regions for reasons that are as yet unclear. Infection at both sites is strongly associated with sexual behavior, but this association does not appear to explain the male predominance of oral HPV infection. Studies of the molecular pathogenesis of HPV-associated HNSCC (predominantly oropharyngeal cancers) are hampered by the lack of a readily detectable intermediate clinical endpoint analogous to cervix intraepithelial neoplasia. Nevertheless, similarities in chromosomal aberrations, gene expression, methylation and microRNA profiles between HPV-positive HNSCC and cervical cancer argue for shared carcinogenic pathways. Treatment approaches to oropharyngeal and cervical cancers are remarkably similar, with the development of HPV-targeted therapies as the ultimate treatment goal. Key research challenges include understanding oral HPV transmission and male predominance, clarifying the role of cofactors, and developing new screening and treatment methods for HPV-associated HNSCC.

Human papillomavirus infections: warts or cancer?

Human papillomaviruses (HPVs) are prevalent pathogens of mucosal and cutaneous epithelia. Productive infections of squamous epithelia lead to benign hyperproliferative warts, condylomata, or papillomas. Persistent infections of the anogenital mucosa by high-risk HPV genotypes 16 and 18 and closely related types can infrequently progress to high-grade intraepithelial neoplasias, carcinomas-in-situ, and invasive cancers in women and men. HPV-16 is also associated with a fraction of head and neck cancers. We discuss the interactions of the mucosotropic HPVs with the host regulatory proteins and pathways that lead to benign coexistence and enable HPV DNA amplification or, alternatively, to cancers that no longer support viral production.

Human papillomavirus and diseases of the upper airway: head and neck cancer and respiratory papillomatosis

Human papillomavirus (HPV) infection is causally associated with benign and malignant diseases of the upper airway, including respiratory papillomatosis and oropharyngeal cancer. Low-risk HPV types 6 and 11 are the predominant cause of papillomatosis, whereas only HPV16 definitively satisfies both molecular and epidemiological causal criteria as a carcinogenic or high-risk type in the upper airway. HPV16 E6/E7 mRNA expression and integration are observed predominantly among oropharyngeal cancers, and experimental models have shown E6/E7 expression to be necessary for the initiation and maintenance of the malignant phenotype of these cancers. From an epidemiological perspective, a strong and consistent association between markers of HPV16 exposure and oropharyngeal cancer has been demonstrated in numerous case-control studies. HPV-positive oropharyngeal cancers have also been shown to be distinct from HPV-negative head and neck squamous cell cancers with regard to risk-factor profiles, molecular genetic alterations, population-level incidence trends over time, and prognosis. Tumor HPV status (as determined by certain HPV16 in situ hybridization assays or certain p16 immunohistochemistry assays) is the strongest determinant of survival for patients with local-regionally advanced oropharyngeal cancer: patients with HPV-positive cancer have at least a 50% improvement in overall survival at 5 years, which is equivalent to an approximate 30% difference in absolute survival. Thus, HPV status determination is now part of the routine diagnostic evaluation for prognostication. Preliminary evidence indicates that a small proportion of head and neck cancers may be caused by additional HPV types (e.g., 18, 31, 33, 35) and that HPV-caused cancers may rarely arise from non-oropharyngeal sites (e.g., the oral cavity, nasopharynx, and larynx). Whether or not HPV vaccination has the potential to prevent oral HPV infections that lead to cancer or papillomatosis in the upper airway is currently unknown, as is the potential for secondary prevention with HPV detection. This article forms part of a special supplement entitled "Comprehensive Control of HPV Infections and Related Diseases" Vaccine Volume 30, Supplement 5, 2012.

HPV-related methylation signature predicts survival in oropharyngeal squamous cell carcinomas

High-risk types of human papilloma virus (HPV) are increasingly associated with oropharyngeal squamous cell carcinoma (OPSCC). Strikingly, patients with HPV-positive OPSCC are highly curable with ionizing radiation and have better survival compared with HPV-negative patients, but the underlying molecular mechanisms remain poorly understood. We applied an array-based approach to monitor global changes in CpG island hypermethylation between HPV-negative and HPV-positive OPSCCs and identified a specific pattern of differentially methylated regions that critically depends on the presence of viral transcripts. HPV-related alterations were confirmed for the majority of candidate gene promoters by mass spectrometric, quantitative methylation analysis. There was a significant inverse correlation between promoter hypermethylation of ALDH1A2, OSR2, GATA4, GRIA4, and IRX4 and transcript levels. Interestingly, Kaplan-Meier analysis revealed that a combined promoter methylation pattern of low methylation levels in ALDH1A2 and OSR2 promoters and high methylation levels in GATA4, GRIA4, and IRX4 promoters was significantly correlated with improved survival in 3 independent patient cohorts. ALDH1A2 protein levels, determined by immunohistochemistry on tissue microarrays, confirmed the association with clinical outcome. In summary, our study highlights specific alterations in global gene promoter methylation in HPV-driven OPSCCs and identifies a signature that predicts the clinical outcome in OPSCCs.

Focal aberrations indicate EYA2 and hsa-miR-375 as oncogene and tumor suppressor in cervical carcinogenesis

Cervical cancer results from persistent infection with high-risk human papillomavirus (hrHPV). Common genetic aberrations in cervical (pre)cancers encompass large genomic regions with numerous genes, hampering identification of driver genes. This study aimed to identify genes functionally involved in HPV-mediated transformation by analysis of focal aberrations (<3 Mb) in high-grade cervical intraepithelial neoplasia (hgCIN). Focal chromosomal aberrations were determined in high-resolution array comparative genomic hybridization data of 60 hgCIN. Genes located within focal aberrations were validated using 2 external gene expression datasets or qRT-PCR. Functional roles of candidate genes EYA2 (20q13) and hsa-miR-375 (2q35) were studied by siRNA-mediated knock-down and overexpression, respectively, in hrHPV-containing cell lines. We identified 74 focal aberrations encoding 305 genes. Concurrent altered expression in hgCIN and/or cervical carcinomas compared with normal cervical samples was shown for ATP13A3, HES1, OPA1, HRASLS, EYA2, ZMYND8, APOBEC2, and NCR2. Gene silencing of EYA2 significantly reduced viability, migratory capacity, and anchorage-independent growth of HPV16-transformed keratinocytes. For hsa-miR-375, a direct correlation between a (focal) loss and significantly reduced expression was found. Downregulation of hsa-miR-375 expression was confirmed in an independent series of cervical tissues. Ectopic expression of hsa-miR-375 in 2 cervical carcinoma cell lines reduced cellular viability. Our data provide a proof of concept that chromosomal aberrations are actively contributing to HPV-induced carcinogenesis and identify EYA2 and hsa-miR-375 as oncogene and tumor suppressor gene, respectively.

The role of cetuximab in the management of head and neck cancers

INTRODUCTION

The standard of care for patients with locally-advanced head and neck cancer is chemoradiation or surgical resection followed by radiation treatment with or without chemotherapy and despite aggressive, multimodality therapies with their associated toxicities, attempts are being made to improve efficacy while reducing toxicity. Cetuximab is a chimeric mAb directed against the EGFR that showed clinical activity in squamous cell carcinoma of head and neck (SCCHN).

AREAS COVERED

Cetuximab is beneficial in recurrent and metastatic setting, as well as in the definitive setting. In a landmark study by Bonner et al., cetuximab was found to be effective in prolonging survival in conjunction with radiation treatment in locally-advanced tumors versus radiation therapy alone. The Erbitux in First-Line Treatment of Recurrent or Metastatic Head and Neck Cancer (EXTREME) trial also showed an improvement in conjunction with chemotherapy in recurrent and metastatic tumors.

EXPERT OPINION

Cetuximab is an important therapeutic option in SSCHN, and will continue to be used in metastatic and definitive settings. While cetuximab is a valuable tool in the treatment of SCCHN, more studies are needed to maximize the efficacy of this mAb in clinical settings and to identify the subpopulation of patients that truly benefit from its use.

Biology of human papillomavirus infections in head and neck carcinogenesis

The association between human papillomaviruses (HPV) and oral cancer was initially suggested nearly 30 years ago by us. Today, the research interest of head and neck squamous cell carcinoma (HNSCC) has substantially increased. HPV-associated HNSCC is considered a distinct clinical entity with better prognosis than the classical tobacco and alcohol associated cancers. HPV 16 seems to be the main genotype present in HNSCC and it most probably utilizes the same pathways in epithelial cell transformation as established for genital cancer. High-risk HPV E6 and E7 target the well characterized cellular proteins p53 and Rb, respectively. In addition, several other cellular targets of E6 and E7 have been identified. This review gives an overview on the biology of HPV which aids in dissecting the role of HPV in head and neck carcinogenesis. It also summarizes the possible pathways involved in creating new tools for diagnosis and therapy of HPV-associated HNSCC.

Virology and molecular pathogenesis of HPV (human papillomavirus)-associated oropharyngeal squamous cell carcinoma

The current literature fully supports HPV (human papillomavirus)-associated OPSCC (oropharyngeal squamous cell carcinoma) as a unique clinical entity. It affects an unambiguous patient population with defined risk factors, has a genetic expression pattern more similar to cervical squamous cell carcinoma than non-HPV-associated HNSCC (head and neck squamous cell carcinoma), and may warrant divergent clinical management compared with HNSCC associated with traditional risk factors. However, a detailed understanding of the molecular mechanisms driving these differences and the ability to exploit this knowledge to improve clinical management of OPSCC has not yet come to fruition. The present review summarizes the aetiology of HPV-positive (HPV+) OPSCC and provides a detailed overview of HPV virology and molecular pathogenesis relevant to infection of oropharyngeal tissues. Methods of detection and differential gene expression analyses are also summarized. Future research into mechanisms that mediate tropism of HPV to oropharyngeal tissues, improved detection strategies and the pathophysiological significance of altered gene and microRNA expression profiles is warranted.

Genomic aberrations relate early and advanced stage ovarian cancer

Background

Because of the distinct clinical presentation of early and advanced stage ovarian cancer, we aim to clarify whether these disease entities are solely separated by time of diagnosis or whether they arise from distinct molecular events.

Methods

Sixteen early and sixteen advanced stage ovarian carcinomas, matched for histological subtype and differentiation grade, were included. Genomic aberrations were compared for each early and advanced stage ovarian cancer by array comparative genomic hybridization. To study how the aberrations correlate to the clinical characteristics of the tumors we clustered tumors based on the genomic aberrations.

Results

The genomic aberration patterns in advanced stage cancer equalled those in early stage, but were more frequent in advanced stage (p = 0.012). Unsupervised clustering based on genomic aberrations yielded two clusters that significantly discriminated early from advanced stage (p = 0.001), and that did differ significantly in survival (p = 0.002). These clusters however did give a more accurate prognosis than histological subtype or differentiation grade.

Conclusion

This study indicates that advanced stage ovarian cancer either progresses from early stage or from a common precursor lesion but that they do not arise from distinct carcinogenic molecular events. Furthermore, we show that array comparative genomic hybridization has the potential to identify clinically distinct patients.

Electronic supplementary material

The online version of this article (doi:10.1007/s13402-012-0077-5) contains supplementary material, which is available to authorized users.

New Concepts for Translational Head and Neck Oncology: Lessons from HPV-Related Oropharyngeal Squamous Cell Carcinomas

Human papillomavirus (HPV) infection is well established as an etiological agent responsible for a number of pathologies affecting the stratified epithelia of skin and anogenital sites. More recently, the infection by (mucosal) high-risk HPV types has also been found to be causally associated with squamous cell carcinoma in the head and neck region (HNSCC), especially in the oropharynx. Intriguingly, HPV-related oropharyngeal squamous cell carcinomas (OPSCC) represent a distinct clinical entity compared to HPV-negative tumors with particular regard to treatment–response and survival outcome. The association between HPV infection and OPSCC may therefore have important implications for the prevention and/or treatment of OPSCC. The improved survival of patients with HPV-related tumors also raises the question, as to whether a better understanding of the underlying differences may help to identify new therapeutic concepts that could be used in targeted therapy for HPV-negative and improved therapy for HPV-positive cancers. This review summarizes the most recent advances in our understanding of the molecular principles of HPV-related OPSCC, mainly based on functional genomic approaches, but also emphasizes the significant role played by the tumor microenvironment, especially the immune system, for improved clinical outcome and differential sensitivity of HPV-related tumors to current treatment options.

[HPV-associated head and neck cancer. The basics of molecular and translational research]

Translational research refers to the interfaces between preclinical research and targeted short- and medium-term developments through to clinical standards. There are two distinct groups of oropharyngeal malignancies: those caused by tobacco and alcohol abuse and those caused by HPV infection. Although the prognosis of patients in the latter group is significantly better, this is not taken into consideration in the choice of treatment. However, less intensive use of radiotherapy, chemotherapy, or surgery, as well as targeted multimodal therapeutic approaches, is under research. This article summarizes the main events in the HPV life cycle, with emphasis on carcinogenic mechanisms and potential new molecular targets. Identifying distinct tumor entities of the oropharynx enables the design and development of new preventive and therapeutic strategies to reduce the incidence and mortality of HPV-associated oropharyngeal cancers in the near future.

HPV and head and neck cancer

Head and neck cancer is frequent worldwide and oropharyngeal locations are presently sharply on the increase, in relation with an increasing incidence of oropharyngeal infection by oncogenic type-16 human papillomavirus (HPV). The clinical and biologic profile of these patients is distinct from that of other oropharyngeal carcinoma patients, with earlier onset, cystic cervical nodes and basaloid carcinoma histopathology. Detection of intratumoral viral DNA is essential to confirm the role of HPV, and E6/E7 mRNA expression is the most relevant indicator for stratification. Several methods can reveal intratumoral oncogenic HPV DNA, but PCR with hybridization is the most sensitive and most widely used. According to several reports, prognosis in terms of survival and locoregional control is better in HPV-positive oropharyngeal carcinoma than in oropharyngeal carcinoma associated with smoking and alcohol consumption. The future lies in vaccination, but further studies will determine whether the rate of oropharyngeal carcinoma falls in women vaccinated against cervical cancer.

DNA copy number alterations in endobronchial squamous metaplastic lesions predict lung cancer

RATIONALE

Autofluorescence bronchoscopy (AFB) is a valid strategy for detecting premalignant endobronchial lesions. However, no biomarker can reliably predict lung cancer risk of subjects with AFB-visualized premalignant lesions.

OBJECTIVES

The present study set out to identify AFB-visualized squamous metaplastic (SqM) lesions with malignant potential by DNA copy number profiling.

METHODS

Regular AFB examinations in 474 subjects at risk of lung cancer identified six subjects with SqM lesions at baseline, and carcinoma in situ or carcinoma (carcinoma in situ or greater) at the initial SqM site at follow-up bronchoscopy. These progressive SqM lesions were compared for immunostaining pattern and array comparative genomic hybridization-based chromosomal profiles with 23 SqM lesions of subjects who remained cancer-free. Specific DNA copy number alterations (CNAs) linked to cancer risk were identified and accuracy of CNAs to predict endobronchial cancer in this series was determined.

MEASUREMENTS AND MAIN RESULTS

At baseline, p53, p63, and Ki-67 immunostaining were not predictive for a differential clinical outcome of SqM lesions. The mean number of CNAs in baseline SqM of cases was significantly higher compared with control subjects (P < 0.01). Chromosomal regions significantly more frequently altered in SqM of cases were 3p26.3-p11.1, 3q26.2-q29, 9p13.3-p13.2, and 17p13.3-p11.2 (family-wise error rate <0.10). CNAs were specifically detected at the site of future cancer. In cases, baseline-detected CNAs persisted in subsequent biopsies taken from the initial site, and levels increased toward cancer progression. In this series, a model based on CNAs at 3p26.3-p11.1, 3q26.2-29, and 6p25.3-24.3 predicted cancer with 97% accuracy.

CONCLUSIONS

The data suggest that the presence of specific CNAs in SqM lesions predict endobronchial cancer.

Integrative genomic approaches in cervical cancer: implications for molecular pathogenesis

Cervical cancer (CC) as a single diagnostic entity exhibits differences in clinical behavior and poor outcomes in response to therapy in advanced tumors. Although infection of high-risk human papillomavirus is recognized as an important initiating event in cervical tumorigenesis, stratification of CC into subclasses for progression and response to treatment remains elusive. Existing knowledge of genetic, epigenetic and transcriptional alterations is inadequate in addressing the issues of diagnosis, progression and response to treatment. Recent technological advances in high-throughput genomics and the application of integrative approaches have greatly accelerated gene discovery, facilitating the identification of molecular targets. In this article, we discuss the results obtained by preliminary integrative analysis of DNA copy number increases and gene expression, utilizing the two most common copy number-gained regions of 5p and 20q in identifying gene targets in CC. These analyses provide insights into the roles of genes such as RNASEN, POLS and SKP2 on 5p, KIF3B, RALY and E2F1 at 20q11.2 and CSE1L, ZNF313 and B4GALT5 at 20q13.13. Future integrative applications using additional datasets, such as mutations, DNA methylation and clinical outcomes, will raise the promise of accomplishing the identification of biological pathways and molecular targets for therapies for patients with CC.

Atypical clinical behavior of p16-confirmed HPV-related oropharyngeal squamous cell carcinoma treated with radical radiotherapy

PURPOSE

To report atypical clinical behavior observed in human papillomavirus (HPV)-related oropharyngeal carcinoma (OPC) treated with radiotherapy.

METHODS AND MATERIALS

A retrospective cohort study was conducted for all newly diagnosed OPC cases treated with radiotherapy on July 1, 2003 to April 30, 2009. HPV positivity was determined by p16 immunostaining in tumors. The incidence of additional malignancies and the pattern of distant metastases (DMs) were compared between the HPV-positive (HPV+) and HPV-negative (HPV-) cohorts.

RESULTS

HPV status was evaluated in 318 of 613 consecutive OPC cases (52%), showing 236 HPV+ and 82 HPV- patients. Compared with HPV-, HPV+ cases were less likely to have additional malignancies (prior: 11% vs. 20%, p = 0.038; synchronous: 1% vs. 9%, p = 0.001; metachronous: 6% vs. 16%, p = 0.003). Whereas the majority (10 of 12) of HPV- additional head-and-neck (HN) mucosal malignancies were in the oral cavity, there was none (0 of 7) in the HPV+ cohort (p < 0.001). HPV+ synchronous HN second primaries (SPs) were in the supraglottis, post-cricoid, and nasopharynx; metachronous HN SPs were in the glottis, supraglottis, and ethmoid plus glottis/post-cricoid region. All SPs that could be tested were HPV+. There was no difference in DM rate (10% vs. 15%, p = 0.272), but HPV+ DMs were more likely to involve multiple organs (46% vs. 0%, p = 0.005) and unusual sites.

CONCLUSIONS

This study reports atypical clinical behavior seen in HPV+ OPC, including multicentric lesions in HN mucosa and DM to multiple organs and unusual sites. The frequency of these events is low, but they may have clinical implications. The routine assessment of HPV status for all OPC is warranted.

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

OBJECTIVES

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

STUDY DESIGN

Contemporary review.

METHODS

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

RESULTS

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

CONCLUSIONS

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

The increasing clinical relevance of human papillomavirus type 16 (HPV-16) infection in oropharyngeal cancer

Human papillomavirus type 16 (HPV-16) has been established beyond doubt as a causative agent in oropharyngeal squamous cell carcinoma (SCC). The incidence of oropharyngeal cancer has risen in recent decades, as has the proportion of patients who have a biologically relevant HPV-16 infection. Combined data from 14 recently published studies (2006-2010) show that 57% of 1316 reported cases of oropharyngeal SCC were HPV-16 positive. They had significantly better prognosis (hazard ratio (HR) for 5-year overall survival range 0.05-0.64), although smoking and higher T stage often appear as confounding factors to this favourable prognostic benefit. HPV-16 therefore has increasing importance as a clinically useful prognostic biomarker, but a benefit in survival has been seen in the use of surgery, radiotherapy, and chemotherapy, so specific changes in the preferred methods of treatment are hard to justify. Future trials that include oropharyngeal SCC will consider HPV-16 routinely as a stratification factor, and its use as a predictive biomarker awaits the development of effective targeted treatments. The undeniable and impressive prognostic significance of HPV-16 should hasten its addition to standard pathological reporting of oropharyngeal SCC, and ultimately to its inclusion in TNM staging systems of the American Joint Committee on Cancer (AJCC) and the International Union against Cancer (UICC).

High-resolution genomic profiling of human papillomavirus-associated vulval neoplasia

Background:

The incidence of human papillomavirus-associated vulval neoplasia is increasing worldwide; yet the associated genetic changes remain poorly understood.

Methods:

We have used single-nucleotide polymorphism microarray analysis to perform the first high-resolution investigation of genome-wide allelic imbalance in vulval neoplasia. Our sample series comprised 21 high-grade vulval intraepithelial neoplasia and 6 vulval squamous cell carcinomas, with paired non-lesional samples used to adjust for normal copy number variation.

Results:

Overall the most common recurrent aberrations were gains at 1p and 20, with the most frequent deletions observed at 2q, 3p and 10. Copy-neutral loss of heterozygosity at 6p was a recurrent event in vulval intraepithelial neoplasia. The pattern of genetic alterations differed from the characteristic changes we previously identified in cutaneous squamous cell carcinomas. Vulval neoplasia samples did not exhibit gain at 5p, a frequent recurrent aberration in a series of cervical tumours analysed elsewhere using an identical protocol.

Conclusion:

This series of 27 vulval samples comprises the largest systematic genome-wide analysis of vulval neoplasia performed to date. Despite shared papillomavirus status and regional proximity, our data suggest that the frequency of certain genetic alterations may differ in vulval and cervical tumours.

Biological and clinical relevance of transcriptionally active human papillomavirus (HPV) infection in oropharynx squamous cell carcinoma

Human papillomaviruses (HPV) are associated with a subset of head and neck squamous cell carcinoma (HNSCC), particularly HPV16. This study analyzed the presence and genotype of high risk HPVs, viral DNA load and transcription of the E6/E7 mRNAs, in 231 consecutive HNSCC. Twelve out of 30 HPV16 DNA-positive tumors displayed high E6/E7 mRNAs levels and were localized in the oropharyngeal region. While HPV-free and non-transcriptionally active HPV-related patients showed similar 5-years survival rates, E6/E7 expression was associated with a better prognosis. This emphasizes the importance of considering the transcriptional status of HPV-positive tumors for patient stratification. A gene expression profiling analysis of these different types of tumors was carried out. The most significant differentially expressed gene was CDKN2A, a known biomarker for HPV-related cancer. Assessing both the expression level of the E6/E7 mRNAs and of CDKN2A in HNSCC is required to detect active HPV infection. Chromosomic alterations were investigated by Comparative Genomic Hybridation (CGH) analysis of tumors with transcriptionally active HPV and HPV-negative tumors. The loss of the chromosomal region 16q was found to be a major genetic event in HPV-positive lesions. A cluster of genes located in 16q21-24 displayed decreased expression levels, notably APP-BP1 that is involved in the modulation of the transcriptional activity of p53. In conclusion, this study highlights important criteria required to predict clinically active HPV infection, identifies new biological pathways implicated in HPV tumorigenesis and increases the understanding of HPV-HNSCC physiopathology that is required to develop new targets for therapy.