The role of human papillomavirus in squamous carcinoma of the head and neck

Relationship between cervical esophageal squamous cell carcinoma and human papilloma virus infection and gene mutations

Cervical esophageal squamous cell carcinoma (CESCC) is rare, accounting for 5% of all esophageal carcinomas. Several diagnostic and predictive markers have been studied. However, to the best of our knowledge, no biomarker is known to determine patient management except the clinical stage. The present study aimed to evaluate whether human papilloma virus (HPV) infection, epidermal growth factor receptor (EGFR) and its pathway-related gene mutations, known to be sensitive biomarkers of oropharyngeal carcinomas, could be used as biomarkers for the prediction of the prognosis of patients with CESCC. The present retrospective study included patients with CESCC who received chemoradiotherapy or surgery. HPV infection and the genomic status of EGFR, KRAS, BRAF, NRAS and PIK3CA of each tumor sample from patients with CESCC were analyzed by in situ hybridizations (ISH) and PCR methods, respectively. The present study included 33 patients with CESCC (male/female, 29/4; median age, 62 years; age range, 41-86 years; clinical stage I/II/III/IV, 2/6/10/15). The present study detected HPV in one patient (3.0%) by ISH and PCR. Concerning the investigation of EGFR and its pathway-related gene mutations, the present study detected 15.1% of EGFR, 6.0% of NRAS, 3.5% of BRAF, 3.0% of KRAS and 3.0% for PIK3CA mutations, with no significant relationship between any gene mutations and the clinical prognostic factors. The HPV-infected patient did not exhibit any gene mutations. The present study indicated that HPV infection, EGFR and its pathway-related gene mutations rarely exist in patients with CESCC. The relationship between these biomarkers and the prognosis in patients with CESCC is still unclear.

Comprehensive immunogenomic landscape analysis of prognosis-related genes in head and neck cancer

Head and neck cancer is the sixth most common malignancy around the world, and 90% of cases are squamous cell carcinomas. In this study, we performed a systematic investigation of the immunogenomic landscape to identify prognostic biomarkers for head and neck squamous cell carcinoma (HNSCC). We analyzed the expression profiles of immune-related genes (IRGs) and clinical characteristics by interrogating RNA-seq data from 527 HNSCC patients in the cancer genome atlas (TCGA) dataset, including 41 HPV+ and 486 HPV- samples. We found that differentially expressed immune genes were closely associated with patient prognosis in HNSCC by comparing the differences in gene expression between cancer and normal samples and performing survival analysis. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses were performed to annotate the biological functions of the differentially expressed immunogenomic prognosis-related genes. Two additional cohorts from the Oncomine database were used for validation. 65, 56 differentially expressed IRGs was associated with clinical prognosis in total and HPV- samples, respectively. Furthermore, we extracted 10, 11 prognosis-related IRGs from 65, 56 differentially expressed IRGs, respectively. They were significantly correlated with clinical prognosis and used to construct the prognosis prediction models. The multivariable ROC curves (specifically, the AUC) were used to measure the accuracy of the prognostic models. These genes were mainly enriched in several gene ontology (GO) terms related to immunocyte migration and receptor and ligand activity. KEGG pathway analysis revealed enrichment of pathways related to cytokine-cytokine receptor interactions, which are primarily involved in biological processes. In addition, we identified 63 differentially expressed transcription factors (TFs) from 4784 differentially expressed genes, and 16 edges involving 18 nodes were formed in the regulatory network between differentially expressed TFs and the high-risk survival-associated IRGs. B cell and CD4 T cell infiltration levels were significantly negatively correlated with the expression of prognosis-related immune genes regardless of HPV status. In conclusion, this comprehensive analysis identified the prognostic IRGs as potential biomarkers, and the model generated in this study may enable an accurate prediction of survival.

A three-lncRNA expression signature predicts survival in head and neck squamous cell carcinoma (HNSCC)

Increasing evidence has shown that long non-coding RNAs (lncRNAs) have important biological functions and can be used as a prognostic biomarker in human cancers. However, investigation of the prognostic value of lncRNAs in head and neck squamous cell carcinoma (HNSCC) is in infancy. In the present study, we analyzed the lncRNA expression data in a large number of HNSCC patients (n=425) derived from The Cancer Genome Atlas (TCGA) to identify an lncRNA expression signature for improving the prognosis of HNSCC. Three lncRNAs are identified to be significantly associated with survival in the training dataset using Cox regression analysis. Three lncRNAs were integrated to construct an lncRNA expression signature that could stratify patients of training dataset into the high-risk group and low-risk group with significantly different survival time (median survival 1.85 years vs. 5.48 years; P=0.0018, log-rank test). The prognostic value of this three-lncRNA signature was confirmed in the testing and entire datasets, respectively. Further analysis revealed that the prognostic power of three-lncRNA signature was independent of clinical features by multivariate Cox regression and stratified analysis. These three lncRNAs were significantly associated with known genetic and epigenetic events by means of functional enrichment analysis. Therefore, our results indicated that the three-lncRNA expression signature can predict HNSCC patients’ survival.

LncRNAs as an intermediate in HPV16 promoting myeloid-derived suppressor cell recruitment of head and neck squamous cell carcinoma

The emerging evidence showed that long noncoding RNAs (lncRNAs) are involved in cell growth and apoptosis as well as cancer progression and metastasis of malignant tumor, however, limited data are available on the role of lncRNAs in human papillomavirus (HPV)-associated Head and neck squamous cell carcinomas (HNSCC). Here, we demonstrated that 23.98% of 196 HNSCC cases in Southwest China could be classified as HPV16 infection. The number of MDSCs in HPV-positive HNSCC was significantly higher than normal control, indicating that HPV infection may promote MDSCs aggregation. Then, we applied an array-based approach to monitor the lncRNA expression between HPV-positive HNSCC, HPV-negative HNSCC and normal oral mucous, and obtained 132 different lncRNAs in different HPV infected states of HNSCC. HOTAIR, PROM1, CCAT1, and MUC19 mRNA levels, determined by qRT-PCR were inversely correlated with MDSCs collection of HPV-associated HNSCC in 2 independent patient cohorts. The results may provide a rationale for the further evaluation of lncRNAs as a molecular target to elucidate the molecular mechanism of HPV promoting MDSCs collection of HNSCC.

Contrasting effects of an Mdm2 functional polymorphism on tumor phenotypes

MDM2, an E3 ubiquitin ligase, is a potent inhibitor of the p53 tumor suppressor and is elevated in many human cancers that retain wild-type p53. MDM2 SNP309G is a functional polymorphism that results in elevated levels of MDM2 (due to enhanced SP1 binding to the MDM2 promoter) thus decreasing p53 activity. Mdm2^SNP309G/G mice are more prone to spontaneous tumor formation than Mdm2^SNP309T/T mice, providing direct evidence for the impact of this SNP in tumor development. We asked whether environmental factors impact SNP309G function and show that SNP309G cooperates with ionizing radiation to exacerbate tumor development. Surprisingly, ultraviolet B light or Benzo(a)pyrene exposure of skin shows that SNP309G allele actually protects against squamous cell carcinoma susceptibility. These contrasting differences led us to interrogate the mechanism by which Mdm2 SNP309 regulates tumor susceptibility in a tissue-specific manner. Although basal Mdm2 levels were significantly higher in most tissues in Mdm2^SNP309G/G mice compared with Mdm2^SNP309T/T mice, they were significantly lower in Mdm2^SNP309G/G keratinocytes, the cell-type susceptible to squamous cell carcinoma. The assessment of potential transcriptional regulators in ENCODE ChIP-seq database identified transcriptional repressor E2F6 as a possible negative regulator of MDM2 expression. Our data show that E2F6 suppresses Mdm2 expression in cells harboring the SNP309G allele but not the SNP309T allele. Thus, Mdm2 SNP309G exhibits tissue-specific regulation and differentially impacts cancer risk.

Site disparities in apoptotic variants as predictors of risk for second primary malignancy in patients with squamous cell carcinoma of the head and neck

Background

FAS/FASL promoter variants are considered in altering transcriptional activity of those genes and consequently alter regulation of cell death. However, no studies have investigated whether tumor sites contribute to the association between FAS/FASL polymorphisms and risk for second primary malignancy (SPM).

Method

In this study, FAS670 A > G, FAS1377 G > A, FASL124 A > G, and FASL844C > T polymorphisms were genotyped in 752 OPC and 777 non-OPC patients. Both univariate and multivariable cox proportional hazard models were used to assess the associations.

Results

The univariate and multivariable analyses showed that patients with index OPC and FASL844 CT/TT genotype had significantly increased risk of SPM (cHR, 2.5; 95 % CI, 1.1–5.8, P = 0.043 and aHR, 2.7; 95 % CI, 1.2–6.0, P = 0.032) compared with those with FASL844 CC genotype as the reference group, while index non-OPC patients with FAS670 AG/GG and FasL844 CT/TT genotypes had significantly increased risk of SPM (cHR, 2.2 and 1.8; 95 % CI, 1.2–5.7 and 1.1–3.2; and P = 0.04 and 0.041, respectively and aHR, 2.4 and 1.7; 95 % CI, 1.1–5.1 and 1.0-3.0; and P = 0.043 and 0.049, respectively) compared with their corresponding AA and CC genotypes . Moreover, patients carrying more FAS/FASL variants significantly increased risk of SPM among index non-OPC patients. The stratified analysis showed that smoking status differently modified the associations between FAS/FASL polymorphisms and risk of SPM among index non-OPC from OPC patients.

Conclusion

These results suggested that FAS/FASL polymorphisms might significantly modify SPM risk among patients with SCCHN in a tumor site-specific manner.

Potentially functional variants of p14ARF are associated with HPV-positive oropharyngeal cancer patients and survival after definitive chemoradiotherapy

Since p14 (ARF) and human papillomavirus (HPV) 16 E6/E7 oncoproteins are important regulators participating in the p53/Rb pathways, genetic variations of p14 (ARF) may modify tumor HPV16 status and survival of HPV16-positive squamous cell carcinoma of the oropharynx (SCCOP) patients. We determined tumor HPV16 status and expression of p14/p53 and genotyped p14 (ARF) -rs3731217 and -rs3088440 polymorphisms in 552 incident SCCOP patients. We found that patients having variant genotypes for each p14 (ARF) polymorphism were approximately two or three times as likely to have HPV16-positive tumors compared with patients with corresponding common homozygous genotype, and such an association was particularly pronounced in patients with variant genotypes of both polymorphisms. After definitive chemoradiotherapy, patients having p14 (ARF) rs3731217 TG/GG variant genotypes had significantly better overall, disease-specific and disease-free survival than those having TT genotype, respectively. Multivariable analysis found that patients with p14 (ARF) -rs3731217 TT genotype had an ~7-, 11- and 3-fold increased risk for death overall, death due to SCCOP and recurrence than those with TG/GG variant genotypes, respectively. Furthermore, such significantly prognostic effect was also found when survival analysis was limited to HPV16-positive patients. Additionally, potentially functional relevance of the two variants was characterized to explore the genotype-phenotype correlation. Our findings indicate p14 (ARF) variants may predict tumor HPV16-positive SCCOP patients and survival.

Trends in head and neck cancers in Peru between 1987 and 2008: Experience from a large public cancer hospital in Lima

BACKGROUND

Few studies have evaluated the trends in head and neck cancer in developing countries. The purpose of this study was to estimate trends in incidence of human papillomavirus-related (HPV-R) and HPV-unrelated (HPV-U) head and neck cancer in Lima, Peru, from 1987 to 2008.

METHODS

Registry data from a single public cancer hospital were used to estimate age and sex-specific incidence rates. Annualized percent change was estimated using Poisson regression.

RESULTS

The rate of total head and neck cancers, HPV-U, and HPV-R was 11.9, 10.9, and 0.8, respectively, per 100,000 person-years. Significant increases in HPV-U head and neck cancer were observed in men aged 30 to 44 (2.5%/year) and women 15 to 29 (4.2%/year), 30 to 44 (3.4%/year), and 60 to 74 (2.0%/year). Significant increases in HPV-R head and neck cancer were observed only among men aged 45 to 59 (9.6%/year).

CONCLUSION

Although increased exposure to tobacco, occupational carcinogens, and changing sexual behaviors could be influencing these trends, additional analyses to assess generalizability of these findings to other regions of Peru are needed.

Modeling gene-environment interactions in oral cavity and esophageal cancers demonstrates a role for the p53 R72P polymorphism in modulating susceptibility

A large number of epidemiological studies have linked a common single-nucleotide polymorphism (SNP) in the human p53 gene to risk for developing a variety of cancers. This SNP encodes either an arginine or proline at position 72 (R72P) of the p53 protein, which can alter the apoptotic activity of p53 via transcriptional and non-transcriptional mechanisms. This SNP has also been reported to modulate the development of human papilloma virus (HPV)-driven cancers through differential targeting of the p53 variant proteins by the E6 viral oncoprotein. Mouse models for the p53 R72P polymorphism have recently been developed but a role for this SNP in modifying cancer risk in response to viral and chemical carcinogens has yet to be established experimentally. Here, we demonstrate that the p53 R72P polymorphism modulates the hyperprolferative, apoptotic and inflammatory phenotypes caused by expression of the HPV16 E6 and E7 oncoproteins. Moreover, the R72P SNP also modifies the carcinogenic response to the chemical carcinogen 4NQO, in the presence and absence of the HPV16 transgene. Our findings confirm several human epidemiological studies associating the codon 72 proline variant with increased risk for certain cancers but also suggest that there are tissue-specific differences in how the R72P polymorphism influences the response to environmental carcinogens.

Human papillomavirus (HPV) infection and the risk of esophageal squamous cell carcinoma

There is currently no consensus on the relationship between human papillomavirus (HPV) infection and the pathogenic process of esophageal squamous cell carcinoma (ESCC). Therefore, a retrospective study was performed to explore the association between HPV infection and ESCC, where 225 patients with diagnosed ESCC and 224 matched controls were enrolled in the study and stratified according to smoking and alcohol consumption. Enzyme-linked immunosorbent assay was used to determine seropositivity to HPV by the detection of either IgG or IgM anti-HPV antibodies. In the non-smoking and non-alcohol-consuming subgroup, the incidence of ESCC of HPV seropositive subjects was similar with that of HPV seronegative subjects (P= 0.737, odds ratio [OR] 1.14, 95% confidence interval [CI] 0.54-2.40). However, in the smoking subgroup, there was a significant difference in the incidence of ESCC between HPV seropositive subjects and HPV seronegative subjects (P= 0.009, OR 2.22, 95% CI 1.22-4.04). In addition, there was a significantly higher association of the development of ESCC in HPV seropositive patients that smoke and drink than those that do not (P < 0.001, OR 10.31, 95% CI 4.04-26.29). Therefore, HPV infection is not an independent risk factor for developing ESCC in the non-smoking and non-alcohol-consuming group. For smokers, however, HPV infection increases the risk of the incidence of ESCC.

Nutrition support and therapy in patients with head and neck squamous cell carcinomas

Head and neck squamous cell carcinomas (HNSCC) present a unique set of challenges in both the treatment of the disease and in support of the patient afflicted with the cancer. A major challenge is the nutritional support of these patients. Often, patients with HNSCC are malnourished at baseline due to an underlying dysphagia. Many others develop dysphagia as a result of their surgical resection and external beam radiation therapy. This dysphagia further exacerbates the chronic dehydration and malnutrition. This article will review strategies to provide nutritional support to HNSCC patients and also to review nutritional strategies that may decrease the morbidity and mortality associated with HNSCC treatment.

An interaction between human papillomavirus 16 E2 and TopBP1 is required for optimum viral DNA replication and episomal genome establishment

In human papillomavirus DNA replication, the viral protein E2 forms homodimers and binds to 12-bp palindromic DNA sequences surrounding the origin of DNA replication. Via a protein-protein interaction, it then recruits the viral helicase E1 to an A/T-rich origin of replication, whereupon a dihexamer forms, resulting in DNA replication initiation. In order to carry out DNA replication, the viral proteins must interact with host factors that are currently not all known. An attractive cellular candidate for regulating viral replication is TopBP1, a known interactor of the E2 protein. In mammalian DNA replication, TopBP1 loads DNA polymerases onto the replicative helicase after the G(1)-to-S transition, and this process is tightly cell cycle controlled. The direct interaction between E2 and TopBP1 would allow E2 to bypass this cell cycle control, resulting in DNA replication more than once per cell cycle, which is a requirement for the viral life cycle. We report here the generation of an HPV16 E2 mutant compromised in TopBP1 interaction in vivo and demonstrate that this mutant retains transcriptional activation and repression functions but has suboptimal DNA replication potential. Introduction of this mutant into a viral life cycle model results in the failure to establish viral episomes. The results present a potential new antiviral target, the E2-TopBP1 interaction, and increase our understanding of the viral life cycle, suggesting that the E2-TopBP1 interaction is essential.

A novel fusion protein-based vaccine comprising a cell penetrating and immunostimulatory peptide linked to human papillomavirus (HPV) type 16 E7 antigen generates potent immunologic and anti-tumor responses in mice

The ultimate success of cancer vaccination is dependent upon the generation of tumor-specific CTLs. In this study, we designed and evaluated a novel fusion protein comprising a cell penetrating and immunostimulatory peptide corresponding to residues 32-51 of the Limulus polyphemus protein (LALF(32-51)) linked to human papillomavirus (HPV) 16 E7 antigen (LALF(32-51)-E7). We demonstrated that LALF(32-51) penetrates the cell membrane and delivers E7 into cells. In a preclinical model of HPV16-induced cervical carcinoma we showed that vaccination with adjuvant-free LALF(32-51)-E7 fusion protein significantly improves the presentation of E7-derived peptides to T-cells in vitro and induces suppression of tumor growth.

Genetic polymorphisms of p21 and risk of second primary malignancy in patients with index squamous cell carcinoma of the head and neck

p21 plays an important role in modulating cell cycle control, inducing apoptosis, and inhibiting cell growth, subsequently affecting cancer risk. We investigated the association between two putatively functional single-nucleotide polymorphisms (SNPs) of p21 (p21 C98A and p21 C70T) among 1282 patients diagnosed with incident squamous cell carcinoma of the head and neck (SCCHN) and risk of second primary malignancy (SPM) in an ongoing molecular epidemiology study. We used Log-rank test and Cox proportional hazard models to assess the association of these two SNPs with SPM-free survival and SPM risk. We found that patients with either p21 variant genotypes of the two polymorphisms had a significantly reduced SPM-free survival compared with patients with either p21 wild-type homozygous genotypes (Log-rank test, P = 0.0016). Compared with patients having the p21 98 CC and p21 70 CC genotypes, the patients having p21 98 CA/AA and p21 70 CT/TT variant genotypes had a significantly greater risk of developing SPM, respectively, [hazard ratio (HR) = 1.80, 95% CI = 1.14-2.82 for p21 C98A and HR = 1.82, 95% confidence interval (CI) = 1.16-2.85 for p21 C70T]. Moreover, after combining the variant genotypes of two SNPs, patients with variant genotypes had a significantly moderately increased risk for SPM compared with patients with no variant genotypes (HR = 2.00, 95% CI = 1.26-3.00), and the risk was particularly pronounced in several subgroups. Our results support an increased risk of SPM after index SCCHN with both p21 polymorphisms individually and in combination.

Distribution of immune cells in head and neck cancer: CD8+ T-cells and CD20+ B-cells in metastatic lymph nodes are associated with favourable outcome in patients with oro- and hypopharyngeal carcinoma

Background

Tumour infiltrating lymphocytes (TIL) are generally considered to represent a host immune response directed against tumour antigens. TIL are also increasingly recognised as possible prognostic parameters. However, the effects observed are variable indicating that results cannot be extrapolated from type of tumour to another. Moreover, it has been suggested that primary solid tumours may be ignored by the immune system and that a meaningful immune response is only mounted in regional lymph nodes.

Methods

We have examined the local distribution of immune cells in tumour-related compartments in head and neck squamous cell carcinomas (HNSCC). In a second step, the prognostic impact of these cells on disease-free survival (DFS) was analysed. A total of 198 tissue cores from 33 patients were evaluated using tissue mircroarray technique and immunohistochemistry. Tumour-infiltrating immune cells were identified using antibodies specific for CD3, CD8, GranzymeB, FoxP3, CD20 and CD68 and quantified using an image analysis system.

Results

We demonstrate a relative expansion of FoxP3⁺ regulatory T-cells (Treg) and of cytotoxic T-cells among tumour infitrating T-cells. We also show that intratumoural CD20⁺ B-cells are significantly more frequent in metastatic deposits than in primary tumours. Furthermore, we observed a reduced number of peritumoural CD8⁺ T-cells in metastatic lymph nodes as compared to univolved regional nodes suggesting a local down-modulation of cellular immunity. All other immune cells did not show significant alterations in distribution. We did not observe an association of tumour infiltrating immune cells at the primary site with outcome. However, increased numbers of intraepithelial CD8⁺ TIL in metastatic tumours as well as large numbers of peritumoural B-cells in lymph node metastases were associated with favourable outcome. Unexpectedly, no effect on patient outcome was observed for Treg in any compartment.

Conclusion

Our results suggest that alterations in lymphocyte distribution in regional lymph nodes rather than at the primary tumour site may be relevant for patient prognosis. Moreover, we demonstrate that in addition to cellular immunity humoral immune responses may be clinically relevant in anti-tumour immunity.

Association of p73 G4C14-to-A4T14 polymorphism with human papillomavirus type 16 status in squamous cell carcinoma of the head and neck in non-Hispanic whites

BACKGROUND

The tumor protein p73 interacts with the human papillomavirus type 16 (HPV-16) oncoproteins E6 and E7, and p73 variation may modify the interaction between p73 protein and HPV-16 oncogenic proteins and contribute to cellular malignant transformation.

METHODS

In this case-case comparison study, the authors analyzed HPV-16 status in tumor specimens and genotyped the p73 G4C14-to-A4T14 polymorphism using genomic DNA from blood of 202 non-Hispanic white patients with squamous cell carcinoma of the head and neck (SCCHN). Odds ratio (OR) and 95% confidence intervals (95% CIs) were calculated in univariate and multivariable logistic regression models to examine the association between the p73 polymorphism and HPV-16 status in SCCHN.

RESULTS

Compared with the p73 GC/GC genotype, the AT/AT and combined GC/AT + AT/AT variant genotypes were associated significantly with HPV-16-positive tumor status among patients with SCCHN (adjusted OR, 5.32; 95% CI, 1.32-21.4; adjusted OR, 1.91; 95% CI, 1.03-3.53, respectively). There was a significant dose-effect relation between the AT allele and HPV-16-positive tumor status in patients with SCCHN (trend test: P = .014). Moreover, the stratified analyses indicated that the association between HPV-16-positive tumor status and the combined p73 GC/AT + AT/AT genotypes was more pronounced among several subgroups of patients who were older, men, ever drinkers, and those with oropharyngeal cancer.

CONCLUSIONS

The p73 polymorphism was associated with HPV-16 status in SCCHN and may serve as a marker of positive HPV-16 tumor status in patients with SCCHN, particularly those with oropharyngeal cancer.

p73 G4C14-to-A4T14 polymorphism and risk of human papillomavirus-associated squamous cell carcinoma of the oropharynx in never smokers and never drinkers

BACKGROUND

The p53 tumor suppressor protein homolog p73 can be inactivated by oncoprotein E6 of human papillomavirus (HPV). Variation in p73 may alter the interaction between the E6 protein and p73 and, thus, alter the risk for HPV-associated carcinogenesis. It is believed that the p73 G4C14-to-A4T14 polymorphism affects p73 function by altering gene expression; however, whether that polymorphism also alters the risk of HPV type 16 (HPV-16)-associated squamous cell carcinoma of the oropharynx (SCCOP) is unknown.

METHODS

The current case-control study included a case group of 188 non-Hispanic white patients with newly diagnosed SCCOP and a control group of 349 healthy individuals. Logistic regression analyses were used to calculate odds ratios (ORs) and 95% confidence intervals (CIs) for cases and controls stratified by p73 genotype, age, sex, smoking status, alcohol use, and HPV-16 status. The effects of p73 genotypes on the risk of HPV-16-associated SCCOP were explored with further stratification by smoking and drinking status.

RESULTS

HPV-16 seropositivity was associated with an increased risk of SCCOP (adjusted OR, 5.98; 95% CI, 3.89-9.20), especially among never smokers (adjusted OR, 13.8; 95% CI, 5.91-32.1), never drinkers (adjusted OR, 14.9; 95% CI, 5.24-42.4), and individuals with p73 variant genotypes (GC/AT and AT/AT; adjusted OR, 7.96; 95% CI, 3.83-16.5). Moreover, the risk of HPV-16-associated SCCOP for individuals who had p73 variant genotypes was particularly high in never smokers and never drinkers.

CONCLUSIONS

The p73 G4C14-to-A4T14 polymorphism may modulate the risk of HPV-16-associated SCCOP, and the p73 variant genotypes may be markers of genetic susceptibility to HPV-16-associated SCCOP, particularly in never smokers and never drinkers.

No high-risk HPV detected in SCC of the oral tongue in the absolute absence of tobacco and alcohol--a case study of seven patients

INTRODUCTION

In recent years, there has been an increase in the number of patients with squamous cell carcinoma (SCC) of the mobile tongue in the absence of tobacco and alcohol. The literature suggests that human papilloma virus (HPV) may be involved in the development of SCC of the head and neck, especially in non-smoking and non-drinking patients. In the oral cavity, however, the presence of the HPV genome has been reported with various percentages. This may be due to misclassification of the oropharyngeal tongue as oral cavity subsite and the use of various detection methods.

MATERIALS AND METHODS

Therefore, we evaluated the role of HPV in seven consecutive non-smoking and non-drinking patients (2003-2006) with a SCC located at the oral, mobile tongue using in situ hybridization and SPF(10)Line Blot 25 polymerase chain reaction assays.

RESULTS

No HPV was detected in these specimens. To further determine whether a relationship exists between HPV and SCC in the absence of tobacco and alcohol, subsequent studies at specific locations are necessary.

Combined effects of the p53 codon 72 and p73 G4C14-to-A4T14 polymorphisms on the risk of HPV16-associated oral cancer in never-smokers

Because p53 and p73 are associated with critical cellular processes and can be inactivated or degraded by the human papillomavirus (HPV) E6 oncoprotein, we investigated the combined effects of p53 codon 72 and p73 G4C14-to-A4T14 polymorphisms on the risk of HPV16-associated oral cancer. We analyzed genotype data from 326 patients with squamous cell carcinoma of the oral cavity or oropharynx and 349 cancer-free controls. We found that HPV16 seropositivity was associated with an increased risk of oral cancer [adjusted odds ratio (OR), 3.42; 95% confidence interval (CI), 2.28-5.13], especially among never-smokers (adjusted OR, 8.20; 95% CI, 3.66-18.4) and subjects with variant genotypes [adjusted OR for p53 Arg/Pro + Pro/Pro (Pro carriers), 5.00; 95% CI, 2.72-9.21; adjusted OR for p73 GC/AT + AT/AT (AT carriers), 3.83; 95% CI, 1.98-7.41]. HPV16 seropositivity was also associated with an significantly increased risk of oral cancer in all three risk groups with combined genotypes [adjusted ORs (95% CIs) were 2.28 (1.15-4.54) for p53 Arg/Arg and p73 GC/GC, the low-risk group; 3.97 (2.14-7.36) for p53 Arg/Arg and p73 AT carriers or p53 Pro carriers and p73 GC/GC, the medium-risk group and 5.11 (2.00-13.0) for p53 Pro carriers and p73 AT carriers, the high-risk group]. Moreover, HPV16-seropositive never-smokers in the high-risk group exhibited an approximately 11-fold greater risk of oral cancer (adjusted OR, 11.3; 95% CI, 1.22-106.0) than did HPV16-seronegative never-smokers in the low-risk group. These findings suggest that the combined variants of p53 and p73 significantly increase the risk of HPV16-associated oral cancer, especially among never-smokers.

Chemoselection as a strategy for organ preservation in advanced oropharynx cancer: response and survival positively associated with HPV16 copy number

PURPOSE

To test induction chemotherapy (IC) followed by concurrent chemoradiotherapy (CRT) or surgery/radiotherapy (RT) for advanced oropharyngeal cancer and to assess the effect of human papilloma virus (HPV) on response and outcome.

PATIENTS AND METHODS

Sixty-six patients (51 male; 15 female) with stage III to IV squamous cell carcinoma of the oropharynx (SCCOP) were treated with one cycle of cisplatin (100 mg/m(2)) or carboplatin (AUC 6) and with fluorouracil (1,000 mg/m(2)/d for 5 days) to select candidates for CRT. Those achieving a greater than 50% response at the primary tumor received CRT (70 Gy; 35 fractions with concurrent cisplatin 100 mg/m(2) or carboplatin (AUC 6) every 21 days for three cycles). Adjuvant paclitaxel was given to patients who were complete histologic responders. Patients with a response of 50% or less underwent definitive surgery and postoperative radiation. Pretreatment biopsies from 42 patients were tested for high-risk HPV.

RESULTS

Fifty-four of 66 patients (81%) had a greater than 50% response after IC. Of these, 53 (98%) received CRT, and 49 (92%) obtained complete histologic response with a 73.4% (47 of 64) rate of organ preservation. The 4-year overall survival (OS) was 70.4%, and the disease-specific survival (DSS) was 75.8% (median follow-up, 64.1 months). HPV16, found in 27 of 42 (64.3%) biopsies, was associated with younger age (median, 55 v 63 years; P = .016), sex (22 of 30 males [73.3%] and five of 12 females [41.7%]; P = .08), and nonsmoking status (P = .037). HPV titer was significantly associated with IC response (P = .001), CRT response (P = .005), OS (P = .007), and DSS (P = .008).

CONCLUSION

Although the numbers in this study are small, IC followed by CRT is an effective treatment for SCCOP, especially in patients with HPV-positive tumors; however, for patients who do not respond to treatment, alternative treatments must be developed.

EGFR, p16, HPV Titer, Bcl-xL and p53, sex, and smoking as indicators of response to therapy and survival in oropharyngeal cancer

PURPOSE

To prospectively identify markers of response to therapy and outcome in an organ-sparing trial for advanced oropharyngeal cancer.

PATIENTS AND METHODS

Pretreatment biopsies were examined for expression of epidermal growth factor receptor (EGFR), p16, Bcl-xL, and p53 as well as for p53 mutation. These markers were assessed for association with high-risk human papillomavirus (HPV), response to therapy, and survival. Patient variables included smoking history, sex, age, primary site, tumor stage, and nodal status.

RESULTS

EGFR expression was inversely associated with response to induction chemotherapy (IC) (P = .01), chemotherapy/radiotherapy (CRT; P = .055), overall survival (OS; P = .001), and disease-specific survival (DSS; P = .002) and was directly associated with current smoking (P = .04), female sex (P = .053), and lower HPV titer (P = .03). HPV titer was significantly associated with p16 expression (P < .0001); p16 was significantly associated with response to IC (P = .008), CRT (P = .009), OS (P = .001), and DSS (P = .003). As combined markers, lower HPV titer and high EGFR expression were associated with worse OS (rho(EGFR) = 0.008; rho(HPV) = 0.03) and DSS (rho(EGFR) = 0.01; rho(HPV) = 0.016). In 36 of 42 biopsies, p53 was wild-type, and only one HPV-positive tumor had mutant p53. The combination of low p53 and high Bcl-xL expression was associated with poor OS (P = .005) and DSS (P = .002).

CONCLUSION

Low EGFR and high p16 (or higher HPV titer) expression are markers of good response to organ-sparing therapy and outcome, whereas high EGFR expression, combined low p53/high Bcl-xL expression, female sex, and smoking are associated with a poor outcome. Smoking cessation and strategies to target EGFR and Bcl-xL are important adjuncts to the treatment of oropharyngeal cancer.

p53 codon 72 polymorphism associated with risk of human papillomavirus-associated squamous cell carcinoma of the oropharynx in never-smokers

The tumor suppressor p53 protein can be bound, degraded and inactivated by the human papillomavirus (HPV) E6 oncoprotein. The p53 protein's susceptibility to this oncoprotein may be influenced by the p53 codon 72 polymorphism, but the role of such a polymorphism in the development of HPV16-associated squamous cell carcinoma of the oropharynx (SCCOP) has not been established. To investigate the role of the p53 codon 72 polymorphism in the risk of HPV16-associated SCCOP, we conducted a hospital-based case-control study of 188 non-Hispanic white patients with newly diagnosed SCCOP and 342 cancer-free control subjects frequency matched by age (+/-5 years), sex, tobacco smoking status and alcohol drinking status. We found that HPV16 seropositivity was associated with an increased risk of SCCOP [adjusted odds ratio (OR), 5.7; 95% confidence interval (CI), 3.7-8.7], especially among never-smokers (adjusted OR, 14.1; 95% CI, 6.0-32.9) and among subjects with the p53 codon 72 variant genotypes [Arginine (Arg)/Proline (Pro) and Pro/Pro] (adjusted OR, 9.2; 95% CI, 4.7-17.7). A significant multiplicative interaction on the risk of SCCOP was also found between the p53 codon 72 polymorphism and HPV16 seropositivity (P = 0.05). Among never-smokers, the risk of SCCOP for those who had both HPV16 seropositivity and p53 codon 72 variant genotypes (Arg/Pro + Pro/Pro) was particularly high (adjusted OR, 22.5; 95% CI, 4.8-106.2). These findings suggest that p53 codon 72 variant genotypes modify the risk of HPV16-associated SCCOP and may be markers of genetic susceptibility to HPV16-associated SCCOP, especially among never-smokers.

Molecular differentiation of early and late stage laryngeal squamous cell carcinoma: an exploratory analysis

BACKGROUND

A current shortcoming in cancer prognostication and treatment is a lack of methods that adequately address the complexity and diversity of the disease. Prognostic marker systems based on single parameters have generally proven inadequate. Thus, multiparametric methods, which rely on many pieces of information, are ideally suited to the grouping of tumor subtypes and the identification of specific patterns of disease progression.

DESIGN

This study investigated, on an exploratory basis, whether genome wide alterations of loss and gain, using a panel of 122 gene probes (112 unique genes), discriminated between early stage (stage 1 and 2) and late stage (stage 3 and 4) laryngeal squamous cell carcinomas (LSCC). The LSCC cohort comprised 29 patients, 12 early and 17 late staged. Formalin-fixed LSCC DNA was interrogated by a genome wide candidate gene panel (122 genes) using the multiplex ligation-dependent probe amplification assay.

RESULTS

Statistical analysis employed the nonparametric Wilcoxon 2-sample test. Significant differences between tumor stages of early versus late were seen for the following genes: ERBB4, CASP2, RECQL4, and BCL7A. Loss of ERBB4 (P=0.045) and BCL7A (P=0.019) significantly discriminated between early and late stage LSCC. Gain of RECQL4 copy number (P=0.043) was associated with late LSCC. Gain of CASP2 (P=0.043) marked early LSCC, whereas loss was associated with late LSCC.

CONCLUSIONS

High-throughput genome wide approaches have the potential to yield discrete gene repertoires of early and late stage LSCC differentiation.

Strategic plans to promote head and neck cancer translational research within the radiation therapy oncology group: a report from the translational research program

Head and neck cancer is the fifth most common cancer in the United States, with an overall survival rate of approximately 40-50%. In an effort to improve patient outcomes, research efforts designed to maximize benefit and reduce toxicities of therapy are in progress. Basic research in cancer biology has accelerated this endeavor and provided preclinical data and technology to support clinically relevant advances in early detection, prognostic and predictive biomarkers. Recent completion of the Human Genome Project has promoted the rapid development of novel "omics" technologies that allow more broad based study from a systems biology perspective. However, clinically relevant application of resultant gene signatures to clinical trials within cooperative groups has advanced slowly. In light of the large numbers of variables intrinsic to biomarker studies, validation of preliminary data for clinical implementation presents a significant challenge and may only be realized with large trials that involve significant patient numbers. The Radiation Therapy Oncology Group (RTOG) Head and Neck Cancer Translational Research Program recognizes this problem and brings together three unique features to facilitate this research: (1) availability of large numbers of clinical specimens from homogeneously treated patients through multi-institutional clinical trials; (2) a team of physicians, scientists, and staff focused on patient-oriented head-and-neck cancer research with the common goal of improving cancer care; and (3) a funding mechanism through the RTOG Seed Grant Program. In this position paper we outline strategic plans to further promote translational research within the framework of the RTOG.

Trends in head and neck cancer incidence in relation to smoking prevalence: an emerging epidemic of human papillomavirus-associated cancers?

The trends in head and neck cancer incidence and smoking prevalence are reviewed, discussing where such trends parallel but also how and why they may not. In the U.S., public health efforts at tobacco control and education have successfully reduced the prevalence of cigarette smoking, resulting in a lower incidence of head and neck cancer. Vigilance at preventing tobacco use and encouraging cessation should continue, and expanded efforts should target particular ethnic and socioeconomic groups. However, an unfortunate stagnation has been observed in oropharyngeal cancer incidence and likely reflects a rising attribution of this disease to oncogenic human papillomavirus, in particular type 16 (HPV-16). For the foreseeable future, this trend in oropharyngeal cancer incidence may continue, but with time the effects of vaccination of the adolescent and young adult female population should result in a lower viral prevalence and hopefully a reduced incidence of oropharyngeal cancer. To hasten the reduction of HPV-16 prevalence in the population, widespread vaccination of adolescent and young adult males should also be considered.

Squamous cell carcinoma of the head and neck in never smoker–never drinkers: A descriptive epidemiologic study

BACKGROUND

While the attributed risk factors for the vast majority of patients with squamous cell carcinoma of the head and neck (SCCHN) are smoking and alcohol abuse, there appears to be a rising proportion of SCCHN patients who report no significant smoking or drinking history. This study reports the demographic and potential risk factors of a large series of never smoker-never drinker (NSND) patients.

METHODS

All subjects were participants in a prospective epidemiologic study of incident SCCHN. We obtained demographic data, clinical characteristics, and potential etiologic factors for 172 NSND patients and 1131 ever smoker-ever drinker (ESED) patients. RESULTS.: NSND patients were more likely to be female and to present at extremes of age, but overall were significantly younger than ESED patients. NSND patients had a higher proportion of oral cavity and oropharyngeal cancers than ESED patients had. Eleven percent of NSND patients (17% of NSND men) reported regular use of noncigarette tobacco products or marijuana, 41% (45% of NSND women) reported regular environmental exposure to tobacco smoke, 24% (36% of NSND men) reported regular occupational exposures to carcinogens/toxins, and 30% had a history of gastroesophageal reflux disease. More than half the NSND patients with an oropharyngeal primary were serologically positive for human papillomavirus type 16.

CONCLUSION

NSND patients with SCCHN are commonly young women with oral tongue cancer, elderly women with gingival/buccal cancer, or young to middle-aged men with oropharyngeal cancer. While several exposures studied may be important to the etiology of a subset of these cancers in NSND patients, it is likely that no single known factor is responsible for a majority of SCCHN in NSNDs.