p53 polymorphism, human papillomavirus infection in the oral cavity, and oral cancer

Effect of TP53 rs1042522 on the susceptibility of patients to oral squamous cell carcinoma and oral leukoplakia: a meta-analysis

Background

There are different and inconsistent conclusions regarding the genetic relationship between the human tumor suppressor p53 (TP53) rs1042522 polymorphism and the risk of oral squamous cell carcinoma (OSCC) and oral leukoplakia (OL). Therefore, the aim of the study was to comprehensively reassess this association through the performance of an updated meta-analysis.

Methods

After searching the available databases, we systematically screened and included the eligible case-control studies, which contain the full genotype frequency data of the TP53 rs1042522 polymorphism for both OSCC/OL patients and the negative control groups. P_A (P-value of the association test) and ORs (odd ratios) with their corresponding 95% CIs (confidence intervals) were calculated to quantitatively evaluate the influence of TP53 rs1042522 on the susceptibility of patients to OSCC or OL.

Results

In total, twenty eligible case-control articles were finally enrolled. Compared with the controls, no increased or decreased risk of OSCC was observed in the cases for six genetic models including allele C vs. G (P_A = 0.741), carrier C vs. G (P_A = 0.853), homozygote CC vs. GG (P_A = 0.085), heterozygote GC vs. GG (P_A = 0.882), dominant GC + CC vs. GG (P_A = 0.969), and recessive CC vs. GG + GC (P_A = 0.980). Furthermore, no statistically significant difference between the cases and controls was detected in most subgroup meta-analyses (P_A > 0.05). For the risk of OL, we did not observe the difference between the cases and controls for most genetic models in the overall meta-analysis and subsequent subgroup analysis (P_A > 0.05). Begg’s test and Egger’s test excluded the large risk of publication bias within the included studies in the meta-analysis of OSCC. The sensitivity analysis indicated the above relatively stable results.

Conclusions

Our updated meta-analysis (based on the current evidence) shows that TP53 rs1042522 may not confer susceptibility to OSCC. In addition, for the first time, we provided evidence regarding the negative association between TP53 rs1042522 and OL risk.

Electronic supplementary material

The online version of this article (10.1186/s12903-018-0603-6) contains supplementary material, which is available to authorized users.

Meta-Analysis Results on the Association Between TP53 Codon 72 Polymorphism With the Susceptibility to Oral Cancer

Objectives: TP53 is an important tumor suppressor gene to maintain genomic integrity, and its mutations increase the susceptibility to oral carcinoma. Previous published studies have reported the relation of TP53 codon 72 polymorphism with the risk of oral carcinoma, but the results remain controversial and inconclusive.

Methods: We therefore utilized meta-analysis based on a comprehensive search in PubMed, EMBASE, and Google of Scholar databases up to August 19, 2017.

Results: Total 3,525 cases and 3,712 controls from 21 case-control studies were selected. We found no significant association between TP53 codon 72 polymorphism and oral carcinoma susceptibility in all genetic contrast models, including subgroup analysis based on control source and ethnicity. Furthermore, TP53 codon 72 polymorphism was not significant associated with oral carcinoma susceptibility in tobacco or alcohol use, and HPV infection status. Our results were confirmed by sensitivity analysis and no publication bias was found.

Conclusions: Taken together, our data indicate that TP53 codon 72 polymorphism is not associated with the susceptibility to oral carcinoma.

p53 Codon 72 Gene Polymorphism Studies and p53 Expression by Immunohistochemistry in Oral Lesions as Risk Factor for Malignancy

Background:

Wild-type p53 nuclear phosphoproteins are critical cell cycle regulatory tumor-suppressor gene. Genetic mutation of p53 gene is common in several head–neck cancers, usually associated with smoking and human papillomavirus (HPV) infection. In India, instead of HPV, tobacco/pan masala chewing is more commonly associated with oral cancer.

Aim:

The aim of this study was to investigate p53 codon 72 gene polymorphism and expression of p53 by immunohistochemistry (IHC) in oral lesions as a risk factor for its association with malignancy.

Materials and Methods:

A total of 41 cases of oral lesions comprising 6 cases of leukoplakia and 35 cases of oral squamous cell carcinoma (OSCC), between 30 and 60 years age and tobacco/pan masala chewers were taken. Molecular analysis of p53 codon 72 gene polymorphism was performed by polymerase chain reaction – restriction fragment length polymorphism for Arg/Arg, Arg/Pro, and Pro/Pro. Tissue expression of p53 was done by IHC.

Results:

Genotype frequencies of 35 carcinoma cases of p53 Arg/Arg, Arg/Pro, and Pro/Pro were 23%, 57%, and 20%, respectively, and six leukoplakia cases of p53 Arg/Arg and Arg/Pro genotype were 50% and 50%, respectively. By IHC for expression of p53 out of 35 cases of OSCC biopsies, 17 (48.57%) had weak staining, 14 cases (40%) showed evidence of p53 protein staining, and four cases (11.42%) showed negative staining. Among six cases of leukoplakia, 3 (50%) showed weak staining and 3 (50%) showed negative results.

Conclusion:

The findings of the study indicate that there is no significant association between p53 codon 72 gene polymorphism with OSCC and leukoplakia associated with tobacco/pan masala chewing.

Oropharyngeal and laryngeal but not oral cancers are strongly associated with high-risk human papillomavirus in 172 Greek patients

A strong and consistent association has been reported between human papillomavirus (HPV) infection and oropharyngeal cancer, whereas a similar link has not yet been clarified in oral and laryngeal cancer. The purpose of this study was to investigate the association between HPV infection and head and neck squamous cell carcinoma (HNSCC) in Greek patients. Cytological or tissue specimens from 172 cases patients with HNSCC and cytological specimens from 91 control subjects were analyzed for HPV DNA detection and genotyping using a microarray-based assay. Multivariate logistic regression was used to estimate odds ratios (ORs) for the association between the presence of HPV infection and HNSCC for each of the tumor site, after adjustment for potential confounders. The adjusted ORs for positivity to high-risk HPV infection for oropharyngeal and laryngeal cancer were 20.3 (95% CI: 1.7-250.1) and 22.8 (95% CI: 2.5-206.2), respectively. High-risk HPV infection was not significantly associated with oral cancer. HPV infection was independently associated with poorly differentiated tumors (OR = 2.8; 95% CI: 1.1-7.5). Our results suggest a strong association of high-risk HPV infection with oropharyngeal and laryngeal cancer. J. Med. Virol. 89:170-176, 2017. © 2016 Wiley Periodicals, Inc.

P53 codon 72 polymorphism, human papillomavirus infection, and their interaction to oral carcinoma susceptibility

Background

Tumor suppressor gene p53 plays an important role in the maintenance of the genomic integrity, and mutation in the gene may alter an individual’s susceptibility to various carcinomas. P53 Arg72Pro or codon 72 polymorphism has been indicated to increase the risk of developing certain cancers such as bladder cancer and cervical cancer. Human papillomavirus (HPV) infection has been shown as a risk factor for certain cancers such as cervical cancer and oral cancer as well, and the HPV oncoprotein E6 may induce the degradation of p53 function. However, the association between p53 Arg72Pro polymorphism and the risk of oral cancer with HPV infection remains inconclusive. Therefore, this meta-analysis involving 5,614 participants was performed to investigate the relations among the p53 Arg72Pro polymorphism, HPV infection, and the risk of developing oral cancer.

Results

A search of the literature by PubMed, Embase, Web of Science, and China National Knowledge Infrastructure databases was conducted to identify studies based on the inclusion and exclusion criteria. Odds ratios with 95 % confidence intervals were combined using a random-effect model or a fixed-effect model. The current study was conducted with 13 studies consisting of 2,413 cases and 3,201 controls. Neither overall analysis nor stratified analyses detected any obvious evidence of association between p53 Arg72Pro polymorphism and oral cancer susceptibility in all genetic models. However, a significant association between p53 Arg72Pro polymorphism and the risk of oral cancer with HPV infection was detected in the Arg/Arg vs. Arg/Pro + Pro/Pro model.

Conclusion

In the current meta-analysis which used the quantitative data synthesis for the first time, our study demonstrated that p53 Arg72Pro polymorphism together with HPV infection might jointly alter an individual’s susceptibility to the risk of oral cancer. Our results suggested that p53 Arg72Pro polymorphism may partly contribute to the pathogenesis of oral cancer development.

TP53 Pro72 allele is enriched in oral tongue cancer and frequently mutated in esophageal cancer in India

Purpose

The tumor suppressor p53 is known to be inactivated frequently in various cancers. In addition, germline polymorphisms in TP53 are known to affect protein function and influence risk of developing different types of cancers. In this study, we analyzed the association of TP53 Pro72Arg polymorphism with squamous cell carcinoma of oral tongue (SCCOT) and esophagus (ESCC) in India.

Methods

We assessed the distribution of TP53 Pro72Arg polymorphism in one hundred and fifteen and eighty two SCCOT and ESCC patients, respectively, with respect to one hundred and ten healthy controls from the same population. In addition, we analyzed association of the polymorphism with several clinico-pathological and molecular parameters.

Results

Pro72 allele was significantly enriched in SCCOT patients compared to the healthy control group but neither allele was enriched in ESCC. Interestingly, Pro72 allele was preferentially mutated in ESCC which was confirmed by analysis of samples heterozygous for Pro72Arg.

Conclusions

Our study revealed the association of Pro72 allele with SCCOT suggesting the effect of this polymorphism on SCCOT risk. Preferential mutation of Pro72 allele exclusively in ESCC indicates the need for further studies to understand the tissue specific effect of p53 polymorphism.

P53 gene codon 72 polymorphism in patients with oral squamous cell carcinoma in the population of northern Iran

Objectives: Squamous cell carcinoma is the most common cancer of the oral cavity, and several etiologic factors are involved in its development. Single nucleotide polymorphism (SNP) of the P53 gene codon 72 (P53c72) changes the structure of the protein and affects its activity. The prevalence of P53c72 different genotypes, which seems to vary with race and geographic location, has shown a strong correlation with many types of human cancers. The aim of this study was to investigate the correlation between P53c72 polymorphism and risk of oral squamous cell carcinoma (OSCC) in the heavily populated Gilan Province in northern Iran. Design of Study: This case-control study was done on 55 paraffin-embedded samples from OSCC patients and 100 samples of non-dysplastic oral cavity lesions. The P53c72 genotypes were determined using the ARMS-PCR method. SPSS-15 software was used for statistical analysis. Results: There were no significant statistical differences found between the prevalence of different P53c72 genotypes in the OSCC group vs. the control. However, the Pro/Pro genotype in OSCC samples showed a strong correlation with age, as 70% of such patients were below 50 years old. Interestingly, a large portion (40%) of the patients with the Pro/Pro genotype had the tumor in the lip area. Conclusions: Although P53c72 polymorphism does not appear to be a predisposing factor for OSCC in the population of Northern Iran, the Pro/Pro genotype could be considered as a risk factor for OSCC in adults below 50 years old and the anatomical location of the tumor.

Key words:OSCC, P53 codon 72 polymorphism, northern Iran.

Association between p53 Arg72Pro polymorphism and the risk of human papillomavirus-related head and neck squamous cell carcinoma: a meta-analysis

This study aimed to investigate the association between p53 Arg72Pro polymorphism and the risk of human papillomavirus (HPV)-related head and neck squamous cell carcinoma (HNSCC) by conducting meta-analysis. The PubMed database was searched for relevant studies until May 30, 2013. Relevant studies were selected and data were extracted by two independent authors. Overall, subgroup, and sensitivity analyses were then conducted using the Comprehensive Meta- Analysis v2.2 software. Wild-genotype ArgArg was considered as reference [odds ratio (OR) = 1.00]. Nine studies involving 1071 HNSCC cases were obtained. Meta-analysis results indicated no association between p53 Arg72Pro polymorphism and the risk of HPV-related HNSCC: for Pro/Pro vs. Arg/Arg, OR = 1.17, 95% confidence interval (CI) = 0.70-1.98; for Arg/Pro vs. Arg/ Arg, OR = 1.25, 95% CI = 0.97-1.72; and for (Pro/Pro + Arg/Pro) vs. Arg/Arg, OR = 1.28, 95% CI = 0.95-1.70. These meta-analysis results were supported by subgroup and sensitivity analysis results. In conclusions, p53 Arg72Pro polymorphism is a potential marker of HP infection-related HNSCC rather than a susceptibility gene polymorphism.

Human papillomavirus and host genetic polymorphisms in carcinogenesis: a systematic review and meta-analysis

BACKGROUND

As the role of human papillomavirus (HPV) in carcinogenesis continues to rise, the role of genetic factors that modify this risk have become increasingly important. In this study, we reviewed the literature for associations between polymorphisms and HPV in carcinogenesis.

OBJECTIVE

To identify any associations of genetic polymorphisms with oncogenic HPV in carcinogenesis and to evaluate the methodology used.

STUDY DESIGN

Systematic literature review of HPV, genetic polymorphisms, and cancer risk. Odds ratios (OR), interaction terms, and p-values were tabulated. Meta-analyses and measures of heterogeneity were estimated using RevMan 5.1.

RESULTS

The cervix was the most frequently studied cancer site followed by the head and neck. Overall risk of cancer (cancer vs. control) was the most common comparison, whereas reports of initiation (pre-cancer vs. control) and progression (cancer vs. pre-cancer) were rare. Case-series and joint-effect of HPV and genotype on risk was evaluated frequently, but the independent effect of either risk factor alone was rarely provided. P53-Arg72Pro was the most commonly studied polymorphism studied. No consistent interaction was detected by meta-analysis in the HPV(+) [OR 0.98 (0.55-1.76)] or the HPV(-) [OR 1.10 (0.76-1.60)] subsets in head and neck cancer risk. Polymorphisms in genes known to encode proteins that physically interact with HPV were infrequently studied.

CONCLUSION

No consistent polymorphism-HPV interactions were observed. Study design, choice of candidate polymorphisms/genes, and a focus on overall risk rather than any specific portions of the carcinogenic pathway may have contributed to lack of significant findings.

Viruses and oral cancer. Is there a link?

Oral squamous cell carcinoma (OSCC) is the most common malignant tumour of the oral cavity. The aetiology of epithelial cancer of the head and neck is considered to be a multifactorial, sequential process. DNA viruses are found in many different cancers and are also capable of transforming cells to a malignant phenotype. Human Papilloma Virus (HPV) has been proposed as risk factors in OSCC development and HPV type 16 is the most important subtype. Other oncogenic virus species i.e., Epstein-Barr Virus and Herpes Simplex Virus Type 1 have been proposed to be involved in oral carcinogenesis. However, no convincing evidence exist that they are an established risk factor in OSCC. Therefore more studies are needed in order to clarify the different aspects of virus involvement. Here, we review the existing literature on viral involvement in oral cancer.

Complex etiology underlies risk and survival in head and neck cancer human papillomavirus, tobacco, and alcohol: a case for multifactor disease

Findings are inconsistent about whether tobacco, alcohol, and human papillomavirus (HPV) are two independent HNC risk factor groups that distinguish an infection-associated cancer from a tobacco/alcohol-associated HNC. We found that cancer in the oral cavity risk was greater in HPV-E6/E7 seropositive/heavy tobacco users (adjusted OR = 3.5) than in HPV-seronegative/heavy tobacco users (adjusted OR = 1.4); and HPV-seropositive/heavy alcohol users (adjusted OR = 9.8) had greater risk than HPV-seronegative/heavy alcohol users (adjusted OR = 3.1). In contrast, the risk of oropharyngeal cancer was greater in the HPV-seronegative/heavy tobacco (adjusted OR = 11.0) than in HPV-seropositive/heavy tobacco (adjusted OR = 4.7) users and greater in HPV-seronegative/heavy alcohol users (adjusted OR = 24.3) compared to HPV-seropositive/heavy alcohol users (adjusted OR = 8.5). Disease-specific and recurrence-free adjusted survival were significantly worse in oropharyngeal HPV-seronegative cases with no survival differences by HPV status seen in oral cavity cases. The association between tobacco/alcohol, HPV, and tumor site is complex. There appear to be distinct tumor site differences in the combined exposure risks, suggesting that different molecular pathways are involved.

Human papillomavirus serologic follow-up response and relationship to survival in head and neck cancer: a case-comparison study

Background

Human papillomavirus high risk (HPV-HR) type 16 is a significant risk factor for head and neck cancers (HNC) independent of tobacco and alcohol. The purpose of this study was to determine whether antibody levels to the HPV-16 oncoproteins E6 and E7 measured in sera collected at baseline (BL) prior to treatment and at two post-treatment follow-up (FU) visits were associated with HNC risk factors or prognosis.

Methods

Presence of antibodies to HPV-16 E6 and E7 was evaluated in 109 newly diagnosed HNC cases with BL and FU blood samples, using the enzyme-linked immunosorbent assay (ELISA).

Results

HPV-16 E6 and/or E7 seropositive HNC cases were associated with higher risk in younger patients (≤ 55 years), more sexual partners (≥ 10), oropharyngeal cancer, worse stage at diagnosis, poorer grade, and nodal involvement. Between BL and FU (median = 8.3 months), there were decreased antibody levels for seropositive E6 (73% vs. 27%, p = 0.02) and seropositive E7 patients (65% vs. 35%, p = 0.09) with 5% of BL E6 and 35% of BL E7 seropositive patients converting to negative status at FU. Overall mortality (OM) was significantly worse among BL E6 seronegative patients than among BL seropositive patients (40.2% vs.13.6%, p = 0.01). There were no disease specific (DS) deaths among BL E6 seropositive vs. 24% in BL E6 seronegative patients (p = 0.01). BL E7 seronegative patients also had higher mortality than BL seropositive patients (OM: 38.2% vs. 20.0%, p = 0.04; DS: 22.5% vs. 5.6%, p = 0.07).

Conclusion

These findings are the first to follow post-treatment OD levels of HPV-16 E6 and E7 in HNC and suggest that these HPV antibodies may be potential prognostic markers of survival in HNC patients.

A novel functional DEC1 promoter polymorphism -249T>C reduces risk of squamous cell carcinoma of the head and neck

Human DEC1 (deleted in esophageal cancer 1) gene is located on chromosome 9q, a region frequently deleted in various types of human cancers, including squamous cell carcinoma of the head and neck (SCCHN). However, only one epidemiological study has evaluated the association between DEC1 polymorphisms and cancer risk. In this hospital-based case-control study, four potentially functional single-nucleotide polymorphisms -1628 G>A (rs1591420), -606 T>C [rs4978620, in complete linkage disequilibrium with -249T>C (rs2012775) and -122 G>A(rs2012566)], c.179 C>T p.Ala60Val (rs2269700) and 3' untranslated region-rs3750505 as well as the TP53 tumor suppressor gene codon 72 (Arg72Pro, rs1042522) polymorphism were genotyped in 1111 non-Hispanic Whites SCCHN patients and 1130 age-and sex-matched cancer-free controls. After adjustment for age, sex and smoking and drinking status, the variant -606CC (i.e. -249CC) homozygotes had a significantly reduced SCCHN risk (adjusted odds ratio = 0.71, 95% confidence interval = 0.52-0.99) compared with the -606TT homozygotes. Stratification analyses showed that a reduced risk associated with the -606CC genotype was more pronounced in subgroups of non-smokers, non-drinkers, younger subjects (defined as ≤57 years), carriers of the TP53 Arg/Arg (rs1042522) genotype, patients with oropharyngeal cancer or late-stage SCCHN. Further in silico analysis revealed that the -249 T-to-C change led to a gain of a transcription factor-binding site. Additional functional analysis showed that the -249T-to-C change significantly enhanced transcriptional activity of the DEC1 promoter and the DNA-protein-binding activity. We conclude that the DEC1 promoter -249 T>C (rs2012775) polymorphism is functional, modulating susceptibility to SCCHN among non-Hispanic Whites.

Significant association of high-risk human papillomavirus (HPV) but not of p53 polymorphisms with oral squamous cell carcinomas in Malaysia

PURPOSE

The purpose of this study was to evaluate the role of HPV and p53 polymorphisms in oral squamous cell carcinomas (OSCC) affecting Malaysian population.

METHODS

We analysed frozen samples from 105 OSCC as well as 105 oral specimens derived from healthy individuals. PCR assays targeting two regions of the virus were used. PCR amplification for the analysis of p53 codon 72 arginine/proline alleles was carried out in a separate reaction.

RESULTS

HPV DNA was detected in 51.4% OSCC samples, while 24.8% controls were found to be HPV positive. HPV was found to be significantly associated with OSCC (P < 0.001, OR = 4.3 after adjustment for habits) when compared to controls. High-risk HPV was found to be significantly associated with OSCC cases (P < 0.05). Demographic profiles of age, gender, race and habits were not associated with HPV presence in cases and controls. However, significantly less HPV positivity was seen in poorly differentiated compared to well-differentiated OSCCs. No significant association was found between HPV positivity and p53 polymorphisms in cases and control groups. Additionally, we found no association of codon 72 polymorphism with oral cancer.

CONCLUSIONS

This study indicates that high-risk HPV infection is one of the contributing factors for OSCCs. HPV 16 was the predominant type found in Malaysian patients with OSCC. Further, we did not find any association between p53 codon 72 polymorphism and HPV infection or between the p53 polymorphism and the risk of oral cancer.

Tobacco and alcohol use increases the risk of both HPV-associated and HPV-independent head and neck cancers

Tobacco, alcohol, and human papillomavirus (HPV) are major risk factors for head and neck cancer (HNC), but it is unclear whether there are two distinct HNC risk groups, one associated with HPV and the other with tobacco/alcohol. Because HPV-positive HNC are clinically distinct from HPV-negative cases in treatment response and with more favorable prognoses, determining whether these differences result from infection alone or in association with other HNC risk factors is important for developing future therapeutic strategies. Incident cases of HNC (n = 201) and age-gender frequency-matched controls (n = 324) were recruited to assess anti-HPV VLP (virus like particles) antibodies 16, 18, 31, and 33. Multivariate logistic regression and stratified analyses were used to calculate adjusted odds ratios (OR). HPV-seronegative and seropositive/heavy tobacco users had similar increased adjusted risks of HNC (HPV-seronegative OR = 2.6, 1.4-5.0; HPV-seropositive OR = 2.3, 1.1-4.8), as did HPV-seronegative (OR = 4.3, 2.1-9.1) versus HPV-seropositive/heavy alcohol users (OR = 3.9, 1.6-9.4). Similar HPV/tobacco/alcohol risk profiles also were seen in oropharyngeal and oral cavity tumor sites. Our finding that tobacco/alcohol use increased the risk of HNC in both HPV-seropositive and HPV-seronegative individuals is consistent with the observation that HPV infection is not a sufficient cause of HNC but requires the accumulation of additional cellular changes.

Study on TP53 codon 72 polymorphisms with oral carcinoma susceptibility

BACKGROUND AND AIMS

Previous published data have implicated TP53 codon 72 polymorphisms as risk factors for various cancers. Growing bodies of studies have been conducted on the association of TP53 codon 72 polymorphisms with susceptibility to oral carcinoma and have yielded inconclusive results. The aim of the present study was to derive a more precise estimation of this relationship.

METHODS

We conducted a search in the relevant databases without a language limitation, covering all papers published until May 2009. The associated literature was acquired through deliberate searching and selected based on the established inclusion criteria for publications.

RESULTS

Nine studies including 1990 cases and 2074 controls were selected. Data were extracted and further analyzed using systematic meta-analyses. Results showed that no significant differences of oral cancer risk were found between individuals carrying homozygote Arg/Arg genotype and those carrying Pro/Pro genotype (OR: 0.96, 95% CI: 0.78-1.19). Likewise, no evidence indicated that individuals with Arg/Arg genotype have a significant risk of oral cancer compared with those with a combined Pro genotype (Arg/Pro+Pro/Pro) (OR: 0.98, 95% CI: 0.85-1.12). Similarly, individuals with a combined Arg genotype (Arg/Pro+Arg/Arg) do not have a marked increased or decreased susceptibility to oral cancer relative to those with homozygote Pro/Pro genotype (OR: 1.00, 95% CI: 0.83-1.21). Moreover, when stratifying for race, results were similar among Asians or Caucasians. In addition, TP53 codon 72 polymorphisms may not associate with oral cancer risks in smokers and HPV infection status.

CONCLUSIONS

No evidence suggests that TP53 codon 72 polymorphisms may be a risk factor for oral carcinoma.

Evidence for vertical transmission of HPV from mothers to infants

Few large studies have evaluated concordance based on a broad spectrum of human papillomavirus (HPV) types in oral and genital specimens of mothers and their recently born infants. This information is important in determining whether HPV vaccines administered prior to pregnancy may be useful for preventing vertical transmission. HPV DNA was positive in 30% of mothers and 1.5% of newborns. Maternal/newborn concordance (HPV+/+ or HPV−/−) was 71%. Among HPV DNA+ mothers, only 3% of their infants were DNA+ and only 1 pair had the same HPV type. Among HPV− women, 0.8% of infants were HPV+. HPV DNA detected in hospitalized newborns reflects current infection transmitted to infants during pregnancy or delivery. None of the mother/baby HPV DNA+ concordance pairs detected viral types found in HPV vaccines suggesting that vaccination prior to pregnancy is unlikely to be efficacious in preventing vertical transmission.

Detection of HPV DNA and immunohistochemical expression of cell cycle proteins in oral carcinoma in a population of Brazilian patients

This study investigated the presence of human papillomavirus (HPV) DNA and viral types in 33 cases of oral squamous cells carcinoma (OSCC) and compared the immunohistochemical expression of the cell-cycle markers p21 and pRb between cases of the disease with and without HPV. DNA was extracted from paraffin-embedded tissue and amplified by PCR for the detection of HPV DNA. Viral typing was performed by dot blot hybridization. Immunohistochemistry was performed by the streptavidin-biotin technique. HPV DNA was detected in 11 (33.33%) of the 33 cases. The prevalent viral type was HPV 18 (81.81%). A significant association was observed between the presence of HPV and immunohistochemical expression of pRb, but not between p21 expression and the presence of the virus. The low frequency of detection of HPV DNA in OSCC suggests a possible participation of the virus in the development and progression of only a subgroup of these tumors.

Does pretreatment seropositivity to human papillomavirus have prognostic significance for head and neck cancers?

BACKGROUND

Human papillomavirus (HPV) is a risk factor for head and neck cancers (HNC), yet HPV-associated tumors have better prognosis than HPV-negative tumors.

METHODS

We evaluated whether pretreatment presence of antibodies to HPV capsids [virus-like particles (VLP)] or to HPV-16 oncoproteins E6 and E7 was a predictor of HPV-positive HNC and clinical outcomes. Sera from 156 HNC patients were tested for antibodies to HPV-16-derived antigens using ELISA. HPV-16 in tumors was evaluated by PCR and DNA sequencing.

RESULTS

HPV-16 antibodies were found in 33% with HPV-16 VLP, 21% with HPV-16 E6, and 21% with E7. HPV-16 was detected in 26% of tumors. There was a strong correlation between detection of HPV-16 tumor DNA and antibodies to HPV-16 E6 or E7 (kappa = 0.7) but not to HPV-16 VLP (kappa = 0.4). Multivariate analyses showed significantly better disease-specific survival in seropositive HPV-16 VLP [hazard ratio (HR), 0.4; 95% confidence interval (95% CI), 0.1-0.9], HPV-16 E6 (HR, 0.1; 95% CI, 0.02-0.5), and HPV-16 E7 (HR, 0.3; 95% CI, 0.1-0.9) cases. Less disease recurrence occurred among those with antibodies to both E6 and E7 compared with those negative to both (P = 0.003). There was better disease-specific survival in patients who were E6 positive at baseline and remained positive at follow-up compared with individuals who were E6 negative at both time points (P = 0.03; kappa = 0.9).

CONCLUSIONS

The presence of antibodies to HPV-16 E6 and E7 is associated with HPV in tumor cells and with better clinical outcomes. These findings suggest that the presence of E6/E7 antibodies before treatment is predictive of better clinical outcomes and that they may serve as biomarkers for selecting targeted therapeutic modalities developed for HPV-associated tumors.

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.

Detection and genotyping of human papillomavirus DNA in samples from healthy Sardinian patients: a preliminary study

The human papillomavirus (HPV) is involved in the development of different benign and malignant lesions that include in particular squamous tumours of the cervix, skin and the respiratory tracts. In particular, the 'high risk' HPV type 16 (HPV 16) causes genito-rectal epithelial cancers and is suspected of causing epithelial cancers of the head and neck. To determine the presence and genotypes of HPV was determined in saliva samples from 164 subjects recruited from the Department of Surgery and Odontostomatological Sciences (University of Cagliari). For this study a sensitive seminested polymerase chain reaction (PCR) method was used to detect HPV-DNA; moreover in all positive samples, HPV genotyping was based on sequencing of the HPV genome L1 region. The results obtained with these patients (who were ethnically homogeneous), showed an interesting percentage of positive samples for HPV-DNA (30 samples out of 164-18.3%). Only two HPV genotypes have been identified in these patients, HPV 16 and HPV 31 with 76.7% and 23.3% of the positive specimens, respectively, both correlating with high carcinogenic risk. This preliminary result leads us to reflect on the presence of HPV in saliva, in particular in young asymptomatic subjects (15.38%), and its prognostic value for the possible incidence in Sardinia of oral carcinoma.

High association of human papillomavirus infection with oral cancer: a case-control study

BACKGROUND

The aim of the present study was to determine the association of high-risk human papillomavirus (HR-HPV) in Mexican individuals with oral squamous cell carcinoma (OSCC) and their association with various risk factors.

METHODS

We designed a matched case-control study. Cases were individuals with newly diagnosed OSCC, age- and sex-matched with controls (1:4). Demographic and clinical data were obtained; also a self-administered questionnaire about sexual behavior was included. DNA from oral brushing was purified to amplify HPV-DNA through MY09/MY11 and GP5+/GP6+ primers and subsequently subjected to sequencing. Conditional regression models were built to calculate odds ratios (ORs) and 95% confidence intervals (CI).

RESULTS

Sixty two cases and 248 controls (53.2% males), median age 62 years (Q1-Q3=54-72 years) were included. HPV prevalence was 43.5% in cases and 17.3% in controls (HR-HPV: 37.1% cases, 9.7% controls). The most frequent types in cases were HPV-16 and HPV-18 (55.6 and 18.5%). The presence of HR-HPV was associated with OSCC (OR=6.2; 95% CI: 2.98-12.97) controlling for the most common risk factors. An interaction between smoking and drinking was detected, and family history of cancer was also significant (OR: 3.61; 95% CI=1.44-8.99). Early age at first sexual intercourse and large number of lifetime sexual partners showed an association with HR-HPV (p=0.019 and p=0.033, respectively).

CONCLUSIONS

Oral HR-HPV was strongly associated with OSCC, suggesting that HPV-16 and -18 are risk factors for oral cancer in Mexican patients. A significant association of tobacco and alcohol was confirmed. In addition, family history of cancer was associated with OSCC. The results underline the role of HPV in OSCC and its multifactorial etiology.

p53 codon 72 polymorphisms in human papillomavirus-negative and human papillomavirus-positive squamous cell carcinomas of the oropharynx

BACKGROUND

Tobacco smoking, alcohol abuse, and high-risk human papillomavirus (HPV) are risk factors in the etiology of oropharyngeal squamous cell carcinomas (SCCs). The TP53 polymorphism, in which an arginine (R) is changed to proline (P) at codon 72, is functionally significant and could therefore be a predisposing genetic defect.

METHODS

The aim of the study was to investigate the role of codon 72 polymorphism by means of double gradient-denaturing gel electrophoresis in 77 oropharyngeal SCC patients including 33 TP53 mutated and 16 HPV-16-positive cases. The controls consisted of 141 consecutive healthy blood donors.

RESULTS

The cases and controls showed significantly different genotype distribution (P = .0005): the frequencies of the RR, RP, and PP genotypes among the cases were, respectively, 81.8%, 10.4%, and 7.8%, as opposed to 59.6%, 33.3%, and 7.1% among the controls, in agreement with the Hardy-Weinberg equilibrium (P = .35). The PP genotype was significantly overrepresented among females (22.2% vs 3.4%; P = .0243) and in HPV-16-positive cases (25.0% vs 3.3%; P = .0152). No segregation was found between either of the codon 72 genotypes and age or TP53 mutations.

CONCLUSIONS

The significantly lower frequency of the RP genotype in the patients as a whole suggests that it has a protective effect on oropharyngeal SCCs. Moreover, the PP genotype may be a risk factor for the development of oropharyngeal SCC by females and the development of HPV-16-related SCC, although the findings need to be validated in a larger number of tumors.

Human papillomavirus seropositivity and risks of head and neck cancer

We examined antibody response to VLP HPV-16, HPV-16 E6 and E7 antibodies as potential seromarkers of HPV-related head and neck cancer (HNC). The study included 204 HNC cases and 326 controls evaluated for HPV presence in sera using ELISAs for anti-HPV VLP antibodies and HPV-16 E6 and/or E7 antibodies, and in tumor tissue using PCR and DNA sequencing. Anti-HPV-16 VLP was detected in 33.8% of cases and 22.4% of controls, anti-E6 in 20.6% of cases and 0.9% of controls and anti-E7 in 18.6% of cases and 0.6% of controls. HPV-16 DNA was detected in 26.1% of tumors. The adjusted risk of HNC was elevated among those seropositive for HPV-16 VLP (odds ratio (OR) = 1.7, 1.1-2.5), E6 (OR = 32.8, 9.7-110.8) or E7 (OR = 37.5, 8.7-161.2). Compared to HPV DNA-negative/seronegative cases, tumor HPV-16 cases had increased risk of detection with anti-VLP antibodies (OR = 6.8, 3.1-14.9). The odds were more pronounced among cases seropositive for E6 (OR = 69.0, 19.3-247) or E7 (OR = 50.1, 14.7-171). Antibodies against E6 or E7 were associated with risk of cancer in the oral cavity (OR = 5.1, 1.2-22.4) and oropharynx (OR = 72.8, 16.0-330), and with disease characteristics: stage, grade and nodal status. Anti-E6 and/or E7 antibodies were found in 74% of tumor HPV-16 positive cases but in only 5% of tumor HPV-negative cases (K =0.7, 0.6-0.8) suggesting good correlation between the serologic marker and HPV tumor status. Antibodies to HPV-16 E6 and/or E7 represent a more specific biomarker than anti-HPV-16 VLP of an HPV-related HNC. Because of the survival advantage of HPV-related HNC, HPV-16 E6/E7 detection may be useful in therapy targeted for HPV-related tumors.

Human papillomavirus infection and oral cancer: a case-control study in Montreal, Canada

The objective of the present study was to examine the association between human papillomavirus (HPV) infection and risk of developing oral cancer. The investigation followed a hospital-based case-control design. Cases consisted of newly diagnosed patients with squamous cell carcinoma of the oral cavity and oropharynx. Controls were frequency matched to cases on gender, age, and hospital. Subjects were interviewed to elicit information on putative risk factors. Oral exfoliated cells were tested for detection of HPV DNA by the PGMY09/11 polymerase chain reaction protocol. Serum antibodies against HPV 16, 18, and 31 viral capsids were detected using an immunoassay technique. Logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CI) of oral cancer according to HPV exposure variables. HPV DNA was detected in 19% of cases (14 out of 72), and 5% of controls (six out of 129). Among tonsil-related cancers (palatine tonsil and base of tongue) viral DNA was detected in 43% of cases (nine out of 21). The OR for tonsil-related cancers for high-risk HPV types was 19.32 (95%CI: 2.3-159.5), after adjustment for socio-demographic characteristics, tobacco, and alcohol consumption. The equivalent OR for HPV 16 seropositivity was 31.51 (95%CI: 4.5-219.7). The ORs of non-tonsillar oral cancers for high risk HPV DNA in oral cells and for seropositivity were 2.14 (95%CI: 0.4-13.0) and 3.16 (95%CI: 0.8-13.0), respectively. These results provide evidence supporting a strong causal association between HPV infection and tonsil-related cancers. The evidence for an etiologic link is less clear for non-tonsillar oral cancers.

Association between the TP53 codon72 polymorphism and oral cancer risk and prognosis

The TP53 codon72 polymorphism has recently been extensively studied to determine the risk factor for carcinogenesis. However, there are few reports about the relationship between the TP53 codon72 polymorphism and oral cancer risk or post treatment prognosis. We evaluated the genotypic distribution of the TP53 codon72 polymorphism in 100 oral cancer cases and 271 non-cancer controls. There were no significant differences in the frequencies of the three genotypes (Arg/Arg, Arg/Pro, Pro/Pro) of the TP53 codon72 polymorphism between oral cancer cases and controls. However, stratifying by smoking status, we found that the adjusted odds ratio for non-smokers with the Pro/Pro genotype was significantly increased (adjusted OR=2.70, 95% confidence interval=1.07-6.82). We also found that the cases with the Pro/Pro genotype tended to have a shorter post-treatment survival compared with those with the Arg/Pro genotype (p=0.06). Our results suggest the Pro/Pro genotype of the TP53 codon72 polymorphism increases oral cancer risk in non-smokers and worsens their prognosis.

Human papillomaviruses in oral squamous cell carcinoma and pre-cancerous lesions detected by PCR-based gene-chip array

Human papillomavirus (HPV) infection is a significant risk factor for uterine cervical carcinoma. Many studies have also demonstrated the presence of HPV in oral epithelia tissue, but the role of HPV infection in oral squamous cell carcinoma (OSCC) is still controversial. The aim of this study was to determine the frequency and type of HPV in OSCC and oral pre-cancerous lesions. DNA samples were collected by cytobrushing from 51 patients with OSCC, 46 with oral pre-cancerous lesions and 90 normal controls. Nested polymerase chain reaction and gene-chip arrays were used to identify the HPV types in the samples. In pre-cancerous lesions, there was a higher frequency of HPV of any type (14/46, OR = 2.844, CI = 1.186-6.816, P = 0.0216) and of low-risk HPV types (9/46, OR = 5.529, CI = 1.597-19.14, P = 0.0096) than in control samples. The prevalence of high-risk types was significantly higher in OSCC than in control lesions (11/51 vs 8/90, OR = 2.819, CI = 1.051-7.558, P = 0.0420) but this was not the case for HPV of any type (13/51 vs 12/90, OR = 2.244, CI = 0.9266-5.337, P = 0.1066). High-risk HPV types are prevalent in OSCC and may play a role in its progression, while low-risk types are associated with oral pre-cancerous lesions.

Association of p53 Codon 72 Polymorphism with Risk of Hypopharyngeal Squamous Cell Carcinoma in Taiwan

BACKGROUND

p53 polymorphism at codon 72 is a known risk marker for various malignancies, but it has not been studied in hypopharyngeal cancer. This study investigated the genotype distribution of p53 codon 72 polymorphism in hypopharyngeal cancer patients and non-cancer controls matched for age, gender, alcohol consumption and smoking habit.

METHODS

Genomic DNA was extracted from peripheral blood cells of 53 patients with hypopharyngeal cancer and 53 non-cancer controls. Codon 72 polymorphism of p53 was identified by polymerase chain reaction-restriction fragment length polymorphism.

RESULTS

Patients with hypopharyngeal cancer had higher frequencies of Pro/Pro (26.4% vs. 13.2%) and Pro/Arg (51.0% vs. 45.3%) but lower frequencies of Arg/Arg (22.6% vs. 45.1%) compared to controls. Compared to Arg/Arg genotypes, Pro/Pro genotypes had a relative risk of hypopharyngeal cancer of 3.667 (95% confidence interval, 1.16-11.56; p = 0.03). As a group, patients with Pro/Pro or Arg/Pro who were carriers of the Pro allele had a higher relative risk of hypopharyngeal cancer compared to Arg homozygous carriers (odds ratio, 2.415; 95% confidence interval, 1.04-5.64; p = 0.04).

CONCLUSION

This study demonstrated that p53 codon 72 Pro homozygosity is associated with a higher risk of developing hypopharyngeal cancer.

Risk assessment of p53 genotypes and haplotypes in tobacco-associated leukoplakia and oral cancer patients from eastern Idia

The role of 3 p53 polymorphisms (16 bp duplication at intron 3, codon 72 Arg/Pro and intron 6 NciI RFLP at np 13494) as potential markers for indicating cancer risk remains inconclusive. In our case-control study consisting of 197 leukoplakia and 310 oral squamous cell carcinoma (SCC) patients and 348 controls, genotype frequencies at these 3 p53 loci were determined by PCR-RFLP method and analyzed by multiple logistic regression to determine the risks of the diseases. The 2/2 genotype at codon 72 of p53 was at risk for developing leukoplakia (OR = 1.6, 95% CI 1.1-2.3), whereas the combination of 1/2 and 2/2 genotypes at intron 3 and 1/1 and 1/2 genotypes at intron 6 conferred a protective effect against leukoplakia and oral SCC development, respectively (OR = 0.5, 95% CI 0.4-0.8 and OR = 0.6, 95% CI 0.5-0.9, respectively). When subjects were stratified according to specific tobacco habit, the risk/protection estimates improved significantly in some cases. Specifically, the exclusive smokers with p53 codon 72 2/2 genotype showed a higher risk of developing leukoplakia (OR = 2.7, 95% CI 1.2-6.3). Furthermore, a particular p53 haplotype 1-2-2 was at risk for both tobacco-associated leukoplakia and oral SCC (OR = 1.5, 95% CI 1.1-1.9 and OR = 1.3, 95% CI 1.1-1.7, respectively). Our results show that both specific p53 genotype and haplotype can indicate risk of tobacco-associated leukoplakia, but risk of development of tobacco-associated oral SCC can be predicted by specific p53 haplotype only.

HPV prevalence and concordance in the cervix and oral cavity of pregnant women

OBJECTIVES

This investigation examined human papillomavirus (HPV) in pregnant women in order to characterize viral prevalence, types and concordance between infection in the cervix and in the oral cavity.

METHODS

A total of 577 pregnant women seeking routine obstetric care were evaluated for HPV infection in their cervix during gestation and immediately before delivery, and in the oral cavity during gestation. Male partners present during the gestational clinic visit also provided a specimen from their oral cavity. HPV assessment was performed by PCR, dot blot hybridization and DNA sequencing. A sexual and health questionnaire was completed by the pregnant women.

RESULTS

HPV prevalence in women was 29% in the cervix and 2.4% in the oral cavity. Among those with both gestational and delivery specimens, 35% were infected at least once and 20% had infection at both intervals. At delivery, 68% of infected women had an oncogenic HPV type in the cervix. There was no type-specific HPV concordance between the two cervical specimens, nor cervical and oral results in women, nor with cervical and oral findings between partners.

CONCLUSION

The lack of association in HPV positivity and types between the cervix and oral cavity in these women suggests that self-inoculation is uncommon. This source of infection does not appear to be from oral contact with a current male partner, since there also was no concordance between partners. These results suggest either other modes of HPV transmission or differences in susceptibility to HPV infection or its clearance in the oral cavity and genital mucosa.

p53 polymorphisms associated with mutations in and loss of heterozygosity of the p53 gene in male oral squamous cell carcinomas in Taiwan

The present study was designed to examine whether different p53 haplotypes of exon 4-intron 3-intron 6 affect the frequency of mutations and loss of heterozygosity (LOH) of the p53 gene in male oral squamous cell carcinomas (OSCCs) in Taiwan. We found that individuals without two Pro-W-G alleles had significantly higher frequency of p53 mutations than those with two Pro-W-G alleles (odds ratio (OR) = 1.98; 95% confidence interval (CI), 1.10-3.56). Out of the 172 p53 gene exon 4 informative male OSCCs, 72 (41.9%) showed LOH. Among these 72 OSCCs with LOH, the frequency of Pro allele loss was 73.6% (53/72). It is notable that alcohol drinking increased the frequency of Arg allele loss (OR = 10.56; 95% CI, 1.23-234.94) in OSCCs from patients who both smoked cigarettes and chewed areca quid (AQ). The frequency of LOH of p53 was not different between p53-mutated OSCCs and p53-normal OSCCs. Thus, the present study revealed that (a) the Arg allele is associated with p53 mutations, (b) the Pro allele is preferentially lost in OSCCs associated with cigarette smoking and AQ chewing, while the frequency of Arg allele loss is increased with alcohol drinking, and (c) haploinsufficiency of p53 is in itself likely to contribute to tumour progression in Taiwanese OSCCs.

p53 Codon 72 Polymorphic Variants, Loss of Allele-Specific Transcription, and Human Papilloma Virus 16 and/or 18 E6 Messenger RNA Expression in Squamous Cell Carcinomas of the Head and Neck

A polymorphism at codon 72 of the human tumor suppressor p53 determines translation into either arginine or proline. Yet, the impact of this amino acid variability on the risk to develop malignant tumors, particularly carcinomas associated with human papilloma virus (HPV) infections, remains unresolved because of contradictory results. To address a potential correlation between the different genotypes and the manifestation of squamous cell carcinomas of the head and neck (SCCHN), we determined the p53 codon 72 in 193 healthy subjects and 122 unselected SCCHN with known HPV status. Furthermore, loss of allele-specific transcription was analyzed in p53 codon 72 heterozygous (Arg/Pro) SCCHN and correlated with HPV 16 and/or 18 E6 transcript expression. We found a moderately increased risk (odds ratio, 1.86; 95% confidence interval, 1.0-3.3) for individuals with germ line heterozygosity to develop SCC of the pharynx. On the other hand, p53 codon 72 polymorphic variants, most notably the Arg/Arg genotype, showed no association with the presence of HPV 16 and/or 18 E6 transcript. Moreover, there was no evidence for HPV-driven selection in SCCHN with allele-specific loss of transcription. Our data suggest that the p53 codon 72 polymorphism has a minor impact on the development of SCCHN.

Analysis of human papillomavirus prevalence and TP53 polymorphism in head and neck squamous cell carcinomas

Head and neck squamous cell carcinoma is a disease associated with tobacco and alcohol abuse. There is evidence that the oncogenic human papillomavirus (HPV) may also be a risk for upper aerodigestive tract cancers. High-risk HPVs encode two early proteins, E6 and E7, that can bind to p53 and pRb, respectively, and induce its degradation or inactivation. The TP53 gene has a single polymorphism at codon 72 of exon 4 that encodes either arginine (Arg) or proline (Pro). The purpose of this study was to evaluate the role of HPV infection and TP53 polymorphism in head and neck cancer. We analyzed 50 tumors, as well swabs of oral mucosa from 142 control individuals, with a polymerase chain reaction technique. The prevalence of HPV in controls was 10.6% and in cancer specimens 16%. The frequency distribution of genotypes in controls was 50% Arg/Arg, 43% Arg/Pro and 7% Pro/Pro; in tumors, it was 52% Arg/Arg, 32% Arg/Pro, and 16% Pro/Pro. Contrary to the results of some studies on cervical cancer, no association between any TP53 genotype or allele and the development of head and neck cancer was observed, regardless of HPV status, except for the Pro/Pro genotype, which is associated with the absence of HPV. The arginine allele appears to protect against head and neck cancers. Also, the data showed that HPV infection results in no increased risk of developing head and neck tumors.

Human papillomavirus in oral exfoliated cells and risk of head and neck cancer

BACKGROUND

Human papillomavirus (HPV) has been associated with the development of head and neck cancers. In this study, we investigated whether the risk factors for head and neck cancer in relation to HPV infection are different from those in the absence of HPV infection and whether HPV detected in oral exfoliated cells is an independent predictor of head and neck cancer risk.

METHODS

We conducted a case-control study in 201 head and neck cancer case patients and 333 control subjects, frequency matched for age and sex. Oral exfoliated cells and tumor tissue were evaluated for HPV using polymerase chain reaction and DNA sequencing to type HPV. Logistic regression was used to calculate odds ratios (ORs) for head and neck cancer with HPV infection and 95% confidence intervals (CIs), adjusted for age, tobacco use, and alcohol consumption.

RESULTS

Oncogenic, or high-risk (HR), HPV types were detected in oral cells from 22.9% of case patients and 10.8% of control subjects. HPV16 was the most frequently detected type (19% versus 10% of case patients and control subjects, respectively). After adjusting for age, tobacco use, and alcohol consumption, the risk of head and neck cancer was statistically significantly greater in individuals with HPV-HR types (adjusted OR = 2.6, 95% CI = 1.5 to 4.2) but not in individuals with nononcogenic HPV types (adjusted OR = 0.8, 95% CI = 0.4 to 1.7) compared with HPV-negative individuals. Compared with individuals who were HPV-negative and did not use alcohol or tobacco, there was a statistically significant synergistic effect between detection of HPV-HR and heavy alcohol consumption (OR = 18.8, 95% CI = 5.1 to 69.5) but an additive effect between detection of HPV-HR and tobacco use (OR = 5.5, 95% CI = 2.1 to 14.1). HPV-HR types detected in oral exfoliated cells were predictive of HPV-HR types in tumor tissue.

CONCLUSION

Infection of oral exfoliated cells with HPV-HR types is a risk factor for head and neck cancer, independent of alcohol and tobacco use, and acts synergistically with alcohol consumption. HPV testing of an oral rinse may be predictive of an HPV-related head and neck cancer.

Age, sexual behavior and human papillomavirus infection in oral cavity and oropharyngeal cancers

There are few well-established patient risk factors associated with human papillomavirus (HPV) infection in cancers of the oral cavity and oropharynx. The purpose of this study was to determine if there were significant different risk factors and tumor characteristics between HPV-positive and HPV-negative cancer cases. HPV was evaluated in cancer tissue and exfoliated oral cells of 193 oral cavity/oropharynx cancer patients using PCR and direct DNA sequencing. A patient questionnaire collected information about risk factors, sexual practices and medical history. The prevalence of HPV high-risk (HR) types was 20% in cancer cases. Three types were identified: HPV-16 (87%), HPV-18 (3%) and HPV-33 (11%). Risk factors for HPV-HR included younger age (< or = 55 years vs. > 55 years; adjusted OR = 3.4; 95% CI = 1.6-7.3) and younger-age cases who had more lifetime sex partners (adjusted OR = 3.8; 95% CI = 1.4-10.1), practiced oral-genital sex (adjusted OR = 4.3; 95% CI = 1.8-10.4) or oral-anal sex (adjusted OR = 19.5; 95% CI = 3.4-113). Compared to HPV-negative cancers, HPV-HR cancers were more likely to have a positive HPV-HR exfoliated oral cytology test (adjusted OR = 7.8; 95% CI = 3.4-18.4), later stage (adjusted OR = 3.0), nodal involvement (adjusted OR = 4.1) and advanced grade (adjusted OR = 3.0). This study shows new evidence that the prevalence of oncogenic mucosal HPV is higher in younger-age oral cavity/oropharynx cancer cases whose sexual practices are typically associated with sexual transmission of the virus. HPV detection also appears to be an indicator of advanced disease characteristics that may require different clinical treatment for this subset of patients. An exfoliated oral cytology test for HPV was a significant predictor of HR types in the cancers, suggesting that an oral rinse may provide an early biomarker of infected tumors.

HPV e carcinogênese oral: revisão bibliográfica

O Papilomavírus humano (HPV) é um vírus ubíquo de DNA, epiteliotrópico, que tem a pele e as mucosas como principais sítios de infecção. Ultimamente, a sua associação com neoplasias benignas e malignas da cavidade oral, principalmente o carcinoma epidermóide, tem sido mais evidente. O seu achado comum em epitélio de mucosa oral normal, amplamente divulgado na literatura, não permite inferências mais precisas quanto ao seu papel na carcinogênese (se agente etiológico principal, coadjuvante ou simples habitante do epitélio de revestimento da mucosa oral). São mais de 100 tipos já identificados, dos quais 24 já foram localizados na cavidade oral. Desses, 4 são particularmente importantes, os tipos 6 e 11 (que estão envolvidos nas lesões benignas do epitélio oral) e 16 e 18 (comprovadamente carcinogênicos e possivelmente envolvidos na etiologia de determinados carcinomas epidermóides orais). A ação desses dois últimos tipos está principalmente associada às oncoproteínas E6 e E7 produzidas pelos mesmos. A E6 liga-se, seqüestra e degrada a p53, importante proteína supressora de tumor. A segunda liga-se e seqüestra a pRb, também supressora de tumor, facilitando a liberação de E2F. Apesar do aprimoramento das técnicas de detecção do HPV nas lesões de mucosa oral, o seu envolvimento direto com os carcinomas orais não foi ainda devidamente comprovado, todavia a sua ação sinérgica com outros carcinógenos químicos e físicos, tais como o fumo e o álcool, em determinados carcinomas epidermóides nos parece o caminho mais correto para explicar a ação do papilomavírus humano na carcinogênese oral.

Human papillomavirus infection as a prognostic factor in carcinomas of the oral cavity and oropharynx

Although studies have established human papillomaviruses (HPVs) as a risk factor for oral and oropharyngeal cancer, it is not clear whether viral infection affects survival in head and neck malignancies. This investigation examined the relationship between HPV and survival in carcinomas of the oral cavity and oropharynx. Formalin-fixed, paraffin-embedded tumor specimens from 139 newly diagnosed cases were tested for HPVs by PCR and DNA sequencing. Patient and tumor characteristics were obtained from questionnaires, pathology reports and cancer registries. Odds ratios (ORs) and relative risks (RRs) were based on logistic and Cox regression models, respectively. HPVs were detected in 21% of the tumors; 83% were HPV-16. Greater risk of HPV infection was associated with males (OR = 2.9, 95% CI = 1.0-8.6), a history of oral-genital sex (OR = 4.2, 95% CI = 1.5-11.7), and oropharyngeal tumors (OR = 10.4, 95% CI = 3.5-31.2). As tobacco usage increased, the odds of HPV detection decreased (OR = 0.97/pack-year, 95% CI = 0.96-0.99). HPV infected patients had better overall survival (RR = 0.3, 95% CI = 0.1-0.8) than those with HPV-negative tumors. There was an interaction between gender and HPV for overall (p = 0.05) and disease-specific (p = 0.03) survival that suggested that HPV infected males had better prognosis than HPV-negative males, but this was not the case among females. HPV status was identified as an independent prognostic factor in oral and oropharyngeal cancers. This result appeared to be gender-specific, suggesting the need for further study of the interaction between HPV and gender on survival.

The p53 network in head and neck cancer

Head and neck squamous cell carcinoma (HNSCC) is the sixth most common cancer worldwide and, despite advances in treatment, still represents a clinical challenge. Inactivation of one or more components of the p53 network is an extremely common event in human neoplasia. In HNSCC, disabling of p53 occurs in a high proportion of cases by mutation in the p53 gene, but other mechanisms of inactivation, such as the presence of human papillomavirus (HPV) and molecular abnormalities in other components of the pathway, are also recognised. The frequent changes occurring in the p53 pathway in HNSCC imply that molecular genetic and immunocytochemical analysis of this critical tumour suppressor network may be of diagnostic and prognostic utility in the clinical management of HNSCC. Further, these changes also provide targets for the development of novel therapeutic approaches to this increasingly common cancer, in which clinical cure for advanced disease remains an elusive goal.

p53 alteration is not an independent prognostic indicator, but affects the efficacy of adjuvant chemotherapy in human pancreatic cancer

BACKGROUND AND OBJECTIVES

Mutations in the p53 gene are found in more than 50% of human cancers and are observed in 60-80% of pancreatic cancers. The clinicopathologic implications of p53 abnormalities and their effects on the efficacy of the adjuvant chemotherapy for pancreatic cancer remain controversial.

METHODS

We investigated the p53 status in core exon-4 to -9 (codon 33-331) by direct DNA sequencing in a series of 72 pancreatic cancers and analyzed the effects of p53 abnormalities on the patients' survival and the efficacy of adjuvant chemotherapy.

RESULTS

p53 mutations were found in 62.5% (45/72) of cases, including 38 point mutations and 7 frameshift mutations. The subtypes of p53 mutations included 68.9% (31/45) transitions and 15.6% (7/45) transversions. 39.5% (15/38) of point mutations were CGT (Arg) to CAT (His) mutation at codon-273 of exon-8. 34.2% (13/38) of point mutations were CGG (Arg) to TGG (Trp) mutation at codon-248 of exon-7. Of seven frameshift mutations, four were seen at exon-4, two at exon-5, and one at exon-6. Of overall cases, p53 abnormalities were not associated with a poorly differentiated grade and an advanced stage. The relationship of adjuvant chemotherapy to survival is approaching statistical significance. Univariate analysis showed that in the p53 mutation group, the patients who received adjuvant chemotherapy had a better survival ratio than that of patients who did not do. Multivariate analysis indicated that in the group with p53 mutations, the significant factors for survival were adjuvant chemotherapy, histologic grade, and clinical stage. However, in the group with a wild-type p53 gene, only histologic grade was a significant factor. In addition, 34.7% (25/72) of the cases harbor p53 polymorphism mutation only at codon-72 of exon-4, which did not show any significant effect on the pathology, prognosis, and efficacy of adjuvant chemotherapy of the pancreatic cancers.

CONCLUSIONS

A p53 abnormality was not an independent factor for evaluating the prognosis of patients with pancreatic cancer, but was a beneficial indicator for selecting a reasonable strategy of adjuvant chemotherapy against pancreatic cancer.

Haplotype structure of TP53 locus in Indian population and possible association with head and neck cancer

It has been proposed that a constellation of three TP53 polymorphisms (intron 3 16 bp duplication, codon 72 BstUI, and intron 6 Nci I RFLP at nt 13494) constitute a haplotype predictive of increased cancer risk. We have estimated the allele frequency of these polymorphisms in three endogamous Indian ethnic populations from three different geographic locations (viz. Iyer from south India, Brahmin from central India and Mahishya from eastern India), as well as in head and neck squamous cell carcinoma (HNSCC) patients, and in ethnically matched normal individuals from the eastern region of India. The genotype distributions and allele frequencies of the three polymorphisms in all but one population, as well as in patients, showed a good fit to Hardy-Weinberg equilibrium. Strong linkage disequilibria were observed between all loci in every population examined, except for the 16bp-Nci I haplotype in the Mahishya population. The Mahishya population differed significantly from the other two populations with respect to differences in allele frequency and haplotype frequency. Although there were no significant differences in genotypic frequency at any of the loci between HNSCC patients and the matched control population, the minor allele frequency of codon 72 and intron 3 16 bp polymorphisms showed significant variation. Variation in overall haplotype frequency between patients and normal individuals was significant (p = 0.036) when two rare haplotypes 2-1-2 and 1-2-1 were combined. The rare haplotype 2-1-2 was found to be modestly over represented in HNSCC patients as compared to normal individuals.

Prevalence and persistence of human papillomavirus in postmenopausal age women

Little is known about the prevalence and persistence of human papillomavirus (HPV) in older women, or about the association between hormone replacement therapy (HRT) use and HPV detection. Like oral contraceptives, HRT hormones may upregulate viral expression and subsequent risk of genital cancer. Postmenopausal women seeking routine gynecologic care were evaluated for HPV infection, testing cervical/vaginal cytology by PCR/DNA sequencing. The prevalence of HPV was 14%; 6% had oncogenic types and 5.8% had persistent infection. Although risk of HPV detection was non-significantly elevated after adjustment for age and HPV-related risk factors among current (adjusted odds ratio (OR)=2.3) and past (adjusted OR=3.2) hormone users compared to never users, past users had a significantly higher risk using combination HRT regimens with increasing duration (adjusted OR=1.8 per year; 95% confidence interval (CI)=1.1-3.1). These findings suggest that a significant percentage of older women are infected with HPV. This may put them at increased risk of genital cancers with longer use of HRTs. Additional studies are needed.

P53 codon 72 polymorphism and risk of squamous cell carcinoma of the head and neck: a case-control study

p53 plays an important role in cell-cycle control, as it facilitates DNA repair activities in response to DNA damage. An aberrant cell cycle impairs DNA repair and increases the probability of mutations that lead to carcinogenesis. The p53 codon 72 Arg/Pro polymorphism has been suggested to be associated with susceptibility to tobacco-related cancers, but this association remains controversial. In this hospital-based case-control study of 304 patients newly diagnosed with squamous cell carcinoma of the head and neck (SCCHN) and 333 cancer-free controls, we evaluated the association between this p53 polymorphism and the risk of SCCHN. All subjects were non-Hispanic whites, and the controls were frequency-matched to the cases by age (+/-5 years), sex and smoking status. Our results suggested that there was no difference in the distributions of p53 codon 72 genotypes between cases and controls (odds ratio (OR)=1.04, 95% confidence interval (CI) 0.75-1.44 for Pro/Pro vs. Arg/Arg and OR=1.01, 95% CI 0.54-1.91 for Arg/Pro vs. Arg/Arg). However, there was evidence that the Pro allele was associated with an early age of onset of SCCHN. The median ages of onset of SCCHN were 59, 56 and 53 years for Arg/Arg, Arg/Pro and Pro/Pro cases, respectively (P=0.151 among three genotypes; P=0.057 for Pro/Pro and Arg/Pro combined vs. Arg/Arg). The median ages at onset of oral cancers were 62, 57 and 51 years for Arg/Arg, Arg/Pro and Pro/Pro, respectively (P=0.091 among three genotypes; P=0.046 for Pro/Pro vs. Arg/Arg; P=0.066 for Pro/Pro and Arg/Pro combined vs. Arg/Arg). While the results suggest that the P53 codon 72 polymorphism may contribute to oral cancer susceptibility, larger studies are needed to confirm these findings.

Is use of hormone replacement therapy associated with increased detection of human papillomavirus and potential risk of HPV-related genital cancers?

Oral contraceptives (OC) are a risk factor for female genital cancers and in vivo studies have shown that progestins stimulate human papillomavirus (HPV) gene expression. A similar role for hormone replacement therapy (HRT) has received little evaluation. Cervical/vaginal specimens were obtained to detect HPV from postmenopausal women (n = 429) seeking annual gynaecologic care. HPV was detected in 14% of women and 4.4% had high-risk, oncogenic types. HPV prevalence was similar across current, past and never HRT users. After adjustment for HPV-related risk factors, current and past user status showed no increased viral detection compared with never users. HRT duration also did not elevate risk among current users. However, longer duration (adj. OR 1.5/year, 95% CI 1.0-2.3) and longer latency (adj. OR 1.2/year, 95% CI 0.9-1.7) among past users of oestrogen/progestin regimens were associated with greater risk. Overall use of HRTs was not associated with HPV detection or disease. However, past users of combination HRTs had significantly greater risk of HPV detection with longer HRT duration and latency, similar to OC-HPV findings. The recommendation that postmenopausal women continue HRTs long term may lead to an increased development of HPV-related diseases, of particular concern among those who discontinue HRTs and subsequent gynaecologic care for early cancer detection.

Oral squamous cell carcinoma; from an hypothesis about a virus, to concern about possible sexual transmission

Nearly two decades ago, we produced the first evidence for the presence of viral nucleic acids in oral squamous cell carcinoma (OSCC) tissues, hypothesising that there may be a viral involvement in at least some OSCC. Subsequently, human papillomaviruses (HPV) in particular have been implicated in OSCC. Antibody responses to HPV are seen and HPV-DNA detected in tumors by us and many others, the virus being mainly HPV-16, the genotype associated with ano-genital cancer. HPV are seen by in situ hybridisation only in tumour and premalignant tissue but not in surrounding normal mucosa suggesting HPV has a causal relationship. HPV may also be integrated in the host genome, further suggesting a causal role. Studies of patients with OSCC have suggested possible sexual transmission of HPV. Recent studies have indicated that HPV may be aetiologically important particularly in some types of oropharyngeal cancer, at least in tonsillar carcinogenesis, and may represent an alternative pathway in carcinogenesis to the established factors of tobacco and alcohol. We have come a very long way in the two decades since our first suggestion of a viral aetiopathogenesis was greeted with incredulity, and data from on-going studies by the International Agency for Research on Cancer, Johns Hopkins Oncology Center and others are eagerly awaited.

Case-control study of vulvar vestibulitis risk associated with genital infections

OBJECTIVE

To evaluate the risk of vulvar vestibulitis syndrome (VVS) associated with genital infections in a case-control study.

METHODS

Diagnosed cases with VVS (n = 69) and age-frequency-matched healthy controls (n = 65) were enrolled from gynecology clinics in a university medical hospital during 1999. They were compared for potential risk factors and symptoms of disease.

RESULTS

VVS cases had a significantly higher risk of physician-reported bacterial vaginosis (BV) (odds ratio, OR = 9.4), Candida albicans (OR = 5.7), pelvic inflammatory disease (PID) (OR = 11.2), trichomoniasis (OR = 20.6), and vulvar dysplasia (OR = l5.7) but no risk associated with human papillomavirus (HPV), ASCUS, cervical dysplasia, genital warts, chlamydia, genital herpes or gonorrhea. Genital symptoms reported significantly more often with VVS included vulvar burning (91 vs. 12%), dyspareunia (81 vs. 15%), vulvar itching (68 vs. 23%) and dysuria (54 vs. 19%) (p < 0.0001).

CONCLUSION

A history of genital infections is associated with an increased risk of VVS. Long-term follow-up case-control studies are needed to elucidate etiologic mechanisms, methods for prevention and effective treatment.