Human papillomavirus in esophageal squamous cell carcinoma in Colombia and Chile

Transcriptionally Active Human Papillomavirus Infection in a Minority of Esophageal Squamous Cell Carcinomas in North America

The role of Human papillomavirus (HPV) infection in esophageal squamous cell carcinoma (ESCC) is a topic of ongoing debate. This study used two screening approaches to look for evidence of HPV infection in esophageal squamous cell carcinoma. We initially checked for HPV infection in a randomly selected group of 53 ESCC cases. We did not detect any tumors positive for high-risk HPV. However, during clinical practice, we identified an HPV-positive ESCC in the distal esophagus, which tested positive for HPV16. This index case was TP53 wild-type, as determined by next-generation DNA sequencing (NGS). Since TP53 mutations are rare in other HPV-driven cancers, we improved our screening method by limiting our screen to a subset of ESCC cases without TP53 mutations. A second screen of 95 ESCCs (from 93 patients) sequenced by NGS revealed an additional 7 ESCCs with TP53 wild-type status (7.3% of the total). Of the 7 cases, 2 cases were found to be high-risk HPV positive. Both patients also tested positive for circulating cell-free HPV DNA and had a complete response to neoadjuvant chemoradiation. The index patient had microscopic residual tumor following neoadjuvant therapy. The patient underwent adjuvant immunotherapy and remained disease free after 22 months of surveillance. This study affirms the transcriptionally active status of high-risk HPV in a minority of ESCC patients in North America.

Frequency of Human Papillomavirus Detection in Chagasic Megaesophagus Associated or Not with Esophageal Squamous Cell Carcinoma

BACKGROUND

Chagasic megaesophagus (CM) as well as the presence of human papillomavirus (HPV) has been reported as etiological factors for esophageal squamous cell carcinoma (ESCC).

OBJECTIVE

We assessed the prevalence of HPV DNA in a series of ESCCs associated or not with CM. Data obtained were further correlated to the pathological and clinical data of affected individuals.

METHODS

A retrospective study was performed on 92 formalin-fixed and paraffin-embedded tissues collected from patients referred to 3 different hospitals in São Paulo, Brazil: Barretos Cancer Hospital, Barretos, São Paulo; Federal University of Triângulo Mineiro, Uberaba, Minas Gerais; and São Paulo State University, Botucatu, São Paulo. Cases were divided into 3 groups: (i) 24 patients with CM associated with ESCC (CM/ESCC); (ii) 37 patients with ESCC without CM (ESCC); and (iii) 31 patients with CM without ESCC (CM). Detection of HPV DNA was assessed in all samples by a genotyping assay combining multiplex polymerase chain reaction and bead-based Luminex technology.

RESULTS

We identified a high prevalence of high-risk HPV in patients in the CM group (12/31, 38.8%) and CM/ESCC (8/24, 33.3%), compared to individuals in the ESCC group (6/37, 16.3%). The individuals in the groups with cancer (ESCC and CM/ESCC) had a higher frequency of HPV-16 (4/9, 44.5% and 2/8, 25.0%). The other types of high-risk HPVs detected were HPV-31, 45, 51, 53, 56, 66, and 73. We also observed in some samples HPV coinfection by more than one viral type. Despite the high incidence of HPV, it did not show any association with the patient's clinical-pathological and molecular (TP53 mutation status) characteristics.

CONCLUSION

This is the first report of the presence of HPV DNA in CM associated with ESCC. HPV infection was more presence in megaesophagus lesions. Further studies are needed to confirm and better understand the role of persistent HPV infection in patients with CM.

P16 and P53 Expression in Esophageal Squamous Cell Carcinoma: A Brief Report From The Experience of South of Iran, and Review of the Literature

Background:

Iran is one of the high-risk countries for esophageal squamous cell carcinoma (ESCC). Human papillomavirus (HPV) has been reported as one of the etiologic, pathogenetic, and prognostic factors in this tumor, especially in high-risk geographic areas. Previous reports from our geographic area, that is, the South of Iran failed to show any evidence of HPV in the cases of ESCC by molecular methods.

Objectives:

In this study, we evaluated P16 and P53 immunohistochemistry (IHC) expression in the cases of esophageal ESCC from Fars province in the South of Iran to find the presence of any correlation between clinicopathologic findings with P16 and P53 expression by IHC as etiologic and prognostic biomarkers. We also tried to compare the results from other geographic areas of Iran and the world.

Results:

P16 and P53 expression were found in 42.9% and 66.12% of ESCCs, respectively. No statistically significant correlation was found between clinicopathologic findings and P16 pr P53 expression.

Conclusion:

Although P16 and P53 expression in ESCC in the South of Iran is significant, there is no statistically significant correlation between clinicopathologic findings and outcome in ESCC and expression of these 2 proteins to be considered as biomarkers. Results from other geographic areas of Iran and the world are also very controversial and inconsistent.

Viruses in Cancers of the Digestive System: Active Contributors or Idle Bystanders?

The human virome, which is a collection of all the viruses that are present in the human body, is increasingly being recognized as an essential part of the human microbiota. The human gastrointestinal tract and related organs (e.g., liver, pancreas, and gallbladder)-composing the gastrointestinal (or digestive) system-contain a huge number of viral particles which contribute to maintaining tissue homeostasis and keeping our body healthy. However, perturbations of the virome steady-state may, both directly and indirectly, ignite/sustain oncogenic mechanisms contributing to the initiation of a dysplastic process and/or cancer progression. In this review, we summarize and discuss the available evidence on the association and role of viruses in the development of cancers of the digestive system.

Relationships of early esophageal cancer with human papillomavirus and alcohol metabolism

BACKGROUND

It is well known that an alcohol consumption habit together with inactive heterozygous aldehyde dehydrogenase-2 (ALDH2) is an important risk factor for the development of esophageal squamous cell carcinoma (ESCC). It remains controversial whether human papillomavirus (HPV) infection contributes to the occurrence/development of ESCC. There has been no study in which the relationship between ESCC and HPV in addition to alcohol dehydrogenase-1B (ADH1B) and ALDH2 genotypes was evaluated.

AIM

To evaluate relationships between HPV infection and development of esophageal cancer, particularly early esophageal cancer, based on ADH1B/ALDH2 polymorphisms.

METHODS

We conducted an exploratory retrospective study using new specimens, and we enrolled 145 patients who underwent endoscopic resection for superficial ESCC and had been observed for more than two years by both physical examination and endoscopic examination in Hokkaido University Hospital. Saliva was collected to analyze genetic polymorphisms of ADH1B/ALDH2. We performed in situ hybridization for resected specimens to detect HPV by using an HPV type 16/18 probe.

RESULTS

HPV was detected in 15 (10.3%) of the 145 patients with ESCC. HPV-positive rates in inactive ALDH2*1/*2 and ALDH2*1/*1 + *2/*2 were 10.8% and 9.8%, respectively (P = 1.00). HPV-positive rates in slow-metabolizing ADH1B*1/*1 and ADH1B*1/*2 + *2/*2 were 12.0% and 10.0%, respectively (P = 0.72). HPV-positive rates in the heavy or moderate alcohol consumption group and the light or rare consumption group were 11.1% and 8.7%, respectively (P = 0.68). HPV-positive rates in the heavy smoking group and the light or no smoking group were 11.8% and 8.3%, respectively (P = 0.59). The 3-year incidence rates of secondary ESCC or head and neck cancer after initial treatment in the HPV-positive and HPV-negative groups were 14.4% and 21.4% (P = 0.22), respectively.

CONCLUSION

In the present situation, HPV status is considered to be less important than other risk factors, such as alcohol consumption, smoking habit, ADH1B/ALDH2 polymorphisms, and HPV status would therefore have no effect on ESCC risk management.

Effect of high-risk human papillomavirus in esophageal squamous cell carcinoma in Somalian and Turkish cases

This study aimed to investigate the role of high-risk human papillomavirus (Hr-HPV) in Somalian and Turkish patients with esophageal squamous cell carcinoma (ESCC). In the sections obtained from paraffin-embedded blocks, the results of invasive tumor, peripheral tumor dysplasia and normal mucosa were examined. Samples containing 45 and 47 ESCC, 46 and 42 dysplasia in Somalian (n = 52) and Turkish (n = 53) cases, respectively, were included in the study. We examined the presence of 14 types of Hr-HPV in ESCC collected from Somalia and Turkey by Aptima® Panther System. Hr-HPV types were not detected in Somalian cases. p16INK4a is positive in 5 (11.4%) tumors and 6 (13%) dysplasia. p53 is positive in 28 (62.2%) tumors and 35 (76.1%) dysplasia. HPV16-18/45 are positive only in one of the Turkish cases. p16INK4a is positive in 5 (10.6%) tumors and 4 (9.5%) dysplasia. p53 is positive in 31 (63.3%) tumors and 24 (57.1%) dysplasia. No reaction was detected in normal mucosa samples in both countries. This study is regional. Although the findings did not reflect the general population, the present study shows that the effect of HPV on carcinogenesis in Somalian and Turkish ESCC patients was not significant.

High-Grade Squamous Intraepithelial Lesion of the Gastroesophageal Junction Secondary to High-Risk Human Papillomavirus

OBJECTIVES

Although the role of human papillomavirus (HPV) in the development of some carcinomas (eg, anogenital and oropharyngeal squamous cell carcinomas) is nondebatable, there is still significant controversy regarding the relationship of HPV and esophageal squamous cell carcinomas (SCCs).

METHODS

All cases were sampled at or near the gastroesophageal junctions in patients with reflux and/or known Barrett esophagus and appear to have been initially sampled "incidentally." Patients were all men, aged 56 to 80 years. None had a known history of other HPV-related disease.

RESULTS

We present four cases of high-grade squamous intraepithelial lesion of the gastroesophageal junction secondary to high-risk HPV that have identical histologic features to similar lesions of the anogenital tract.

CONCLUSIONS

Whether such lesions are at risk for developing into invasive SCC remains unclear.

Lin28/microRNA-let-7a promotes metastasis under circumstances of hyperactive Wnt signaling in esophageal squamous cell carcinoma

Dysregulation of micro (mi)RNA-let-7 has been associated with the development and prognosis of multiple cancer types. Lin28, a RNA-binding protein, plays a conserved role in regulating the maturation of let-7 family proteins. However, few studies have focused on the effects of Lin28/let-7 on Wnt-activated esophageal squamous cell carcinoma (ESCC). Analysis of the expression of let-7a, let-7b and let-7c in clinical tissues revealed that lower let-7a expression was correlated with higher tumor node metastasis staging and recurrence in patients with ESCC. Furthermore, it was demonstrated that let-7a was inversely correlated with the migration and invasion of ESCC cells. In addition, epithelial-mesenchymal transition, and the expression of VEGF-C and MMP9 were effectively decreased by let-7a-mimic or siRNA-Lin28 pretreatment. Mechanistically, Lin28 functioned as the key factor in signal transduction, which regulated the expression of let-7a and the downstream genes along the Wnt signaling pathway. Taken together, these findings identified a biochemical and functional association between Lin28/let-7a, and the Wnt pathway in ESCC cells.

p16INK4a is not a reliable screening marker of HPV infection in esophageal squamous cell carcinoma: evidence from a meta-analysis

BACKGROUND

The role of p16INK4a as a surrogate marker for screening human papillomavirus (HPV) in esophageal squamous cell carcinoma (ESCC) remains controversial.

METHODS

A comprehensive search of EMBASE, PubMed, China National Knowledge Infrastructure and China Biology Medicine was performed from inception to December 27, 2015. A random-effects model was applied to the pooled odds ratios (ORs) with 95% confidence intervals (CIs).

RESULTS

Ten studies were identified (985 cases). The pooled results showed no significant relationship between p16INK4a expression and HPV infection in ESCC based on overall HPV types (OR: 1.79, 95% CI: 0.69-4.66, p = 0.235). Subgroup analysis by HPV detection method showed no statistical significance in either the polymerase chain reaction (PCR) (OR: 1.65, 95% CI: 0.83-3.30, p = 0.154) or in situ hybridization (ISH) group (OR: 2.58, 95% CI: 0.03-268.14, p = 0.689). The pooled OR of the sensitivity analysis ranged from 1.27 (95% CI: 0.58-2.84) to 2.32 (95% CI: 0.95-5.64). Of these studies, 6 involved only high-risk human papillomavirus types (HR-HPV), HPV16 or HPV18. However, similar observations were made for HR-HPV (OR = 1.31, 95% CI: 0.26-6.59, p = 0.741). Subgroup analysis again showed no statistical significance in the PCR group (OR: 0.95, 95% CI: 0.25-3.64, p = 0.940) and ISH group (OR: 2.58, 95% CI: 0.03-268.14, p = 0.689). Sensitivity analysis showed that the pooled OR ranged from 0.69 (95% CI: 0.21-2.22) to 1.89 (95% CI: 0.33-10.86).

CONCLUSIONS

p16INK4a is not a reliable screening marker of HPV infection in ESCC. Further multicenter, large-sample and well-matched prospective studies are still required to illuminate the possible etiological roles of HPV in ESCC.

Human papillomavirus and gastrointestinal cancer: A review

Human papillomavirus (HPV) is one of the most common sexually transmitted infections worldwide. Exposure to HPV is very common, and an estimated 65%-100% of sexually active adults are exposed to HPV in their lifetime. The majority of HPV infections are asymptomatic, but there is a 10% chance that individuals will develop a persistent infection and have an increased risk of developing a carcinoma. The International Agency for Research on Cancer has found that the following cancer sites have a strong causal relationship with HPV: cervix uteri, penis, vulva, vagina, anus and oropharynx, including the base of the tongue and the tonsils. However, studies of the aetiological role of HPV in colorectal and esophageal malignancies have conflicting results. The aim of this review was to organize recent evidence and issues about the association between HPV infection and gastrointestinal tumours with a focus on esophageal, colorectal and anal cancers. The ultimate goal was to highlight possible implications for prognosis and prevention.

Mucosal alpha-papillomaviruses are not associated with esophageal squamous cell carcinomas: Lack of mechanistic evidence from South Africa, China and Iran and from a world-wide meta-analysis

Epidemiological and mechanistic evidence on the causative role of human papillomaviruses (HPV) in esophageal squamous cell carcinoma (ESCC) is unclear. We retrieved alcohol- and formalin-fixed paraffin-embedded ESCC tissues from 133 patients seropositive for antibodies against HPV early proteins, from high-incidence ESCC regions: South Africa, China and Iran. With rigorous care to prevent nucleic acid contamination, we analyzed these tissues for the presence of 51 mucosotropic human alpha-papillomaviruses by two sensitive, broad-spectrum genotyping methods, and for the markers of HPV-transformed phenotype: (i) HPV16/18 viral loads by quantitative real-time PCR, (ii) type-specific viral mRNA by E6*I/E6 full-length RT-PCR assays and (iii) expression of cellular protein p16(INK4a). Of 118 analyzable ESCC tissues, 10 (8%) were positive for DNA of HPV types: 16 (4 tumors); 33, 35, 45 (1 tumor each); 11 (2 tumors) and 16, 70 double infection (1 tumor). Inconsistent HPV DNA+ findings by two genotyping methods and negativity in qPCR indicated very low viral loads. A single HPV16 DNA+ tumor additionally harbored HPV16 E6*I mRNA but was p16(INK4a) negative (HPV16 E1 seropositive patient). Another HPV16 DNA+ tumor from an HPV16 E6 seropositive patient showed p16(INK4a) upregulation but no HPV16 mRNA. In the tumor tissues of these serologically preselected ESCC patients, we did not find consistent presence of HPV DNA, HPV mRNA or p16(INK4a) upregulation. These results were supported by a meta-analysis of 14 other similar studies regarding HPV-transformation of ESCC. Our study does not support the etiological role of the 51 analyzed mucosotropic HPV types in the ESCC carcinogenesis.

Human papillomavirus and its clinical relevance in oesophageal squamous cell carcinoma in a Kurdish population in the west of Iran

Background The aetiological role of Human Papillomavirus (HPV) in oesophageal squamous cell carcinoma (ESCC) was evaluated by assessment of the presence and status of HPV DNA in a Kurdish population in the west of Iran. Methods One hundred and three paraffin-embedded ESCC tissue samples, diagnosed between 2007-2013, were included in the study. DNA was extracted and then HPV presence and genotypes were determined by PCR and INNO-LiPA genotyping, respectively. Results HPV DNA was detected in 11/103 (10.7%) of ESCCs. HPV-18 and HPV-16 genotypes were determined in five and six samples, respectively. Co-infection of HPV-6 was only found with HPV-18 in two cases. There were no statistically significant distinctions between HPV-positive and HPV-negative cases with regard to clinical and pathologic findings. Conclusion The present study indicates that, among a group of Kurdish people in two provinces in the west of Iran, as a low-risk ESCC area, HPV could be one of the risk factors, although in a small proportion of the patients.

Heterozygote of TAP1 Codon637 decreases susceptibility to HPV infection but increases susceptibility to esophageal cancer among the Kazakh populations

Background

The role of human papillomavirus (HPV) may be involved in the development of esophageal cancer (EC) and the polymorphic immune response gene transporter associated with antigen processing (TAP) may be involved in HPV persistence and subsequent cancer carcinogenesis. The current study aims to provide association evidence for HPV with EC, to investigate TAP1 polymorphisms in EC and assess its association with HPV statuses and EC in Kazakhs.

Methods

The HPV genotypes in 361 patients with EC and 66 controls selected from Kazakh population were evaluated using PCR. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was performed to detect two SNPs of TAP1 in 150 cases comprised of 75 HPV⁺ and 75 HPV^- patients and 283 pure ethnic population of Kazakh and evaluate their associations with susceptibility to EC. A case-to-case comparison based on the genotyping results was conducted to address the function of TAP1 variants in the involvement of HPV.

Results

The presence of four HPV genotypes in EC tissues ― including HPV 16, 18, 31, 45 ― was significantly higher at 64.6 % than those in controls at 18.2 % (P < 0.001). Such presence was strongly associated with increased risk of EC (OR 8.196; 95 % CI 4.280–15.964). The infection of HPV16, and multi-infection of 16 and 18 significantly increase the risk for developing EC (OR 4.616, 95 % CI 2.099–10.151; and OR 6.029, 95 % CI 1.395–26.057 respectively). Heterozygote of TAP1 D637G had a significantly higher risk for developing EC (OR 1.626; 95 % CI 1.080–2.449). The odds ratio for HPV infection was significantly lower among carriers of TAP1 D637G polymorphism (OR 0.281; 95 % CI 0.144–0.551).

Conclusions

HPV infection exhibits a strong positive association with the risk of EC in Kazakhs. Heterozygote of TAP1 D637G decreases susceptibility to HPV infection in patients with EC but increases susceptibility to EC among the Kazakh populations.

A systems biology analysis of the changes in gene expression via silencing of HPV-18 E1 expression in HeLa cells

Previous studies have reported the detection of a truncated E1 mRNA generated from HPV-18 in HeLa cells. Although it is unclear whether a truncated E1 protein could function as a replicative helicase for viral replication, it would still retain binding sites for potential interactions with different host cell proteins. Furthermore, in this study, we found evidence in support of expression of full-length HPV-18 E1 mRNA in HeLa cells. To determine whether interactions between E1 and cellular proteins play an important role in cellular processes other than viral replication, genome-wide expression profiles of HPV-18 positive HeLa cells were compared before and after the siRNA knockdown of E1 expression. Differential expression and gene set enrichment analysis uncovered four functionally related sets of genes implicated in host defence mechanisms against viral infection. These included the toll-like receptor, interferon and apoptosis pathways, along with the antiviral interferon-stimulated gene set. In addition, we found that the transcriptional coactivator E1A-binding protein p300 (EP300) was downregulated, which is interesting given that EP300 is thought to be required for the transcription of HPV-18 genes in HeLa cells. The observed changes in gene expression produced via the silencing of HPV-18 E1 expression in HeLa cells indicate that in addition to its well-known role in viral replication, the E1 protein may also play an important role in mitigating the host's ability to defend against viral infection.

Human papillomavirus tumor infection in esophageal squamous cell carcinoma

The association between human papillomavirus (HPV) and esophageal squamous cell carcinoma (ESCC) has been recognized for over three decades. Recently, multiple meta-analyses have drawn upon existing literature to assess the strength of the HPV-ESCC linkage. Here, we review these analyses and attempt to provide a clinically-relevant overview of HPV infection in ESCC. HPV-ESCC detection rates are highly variable across studies. Geographic location likely accounts for a majority of the variation in HPV prevalence, with high-incidence regions including Asia reporting significantly higher HPV-ESCC infection rates compared with low-incidence regions such as Europe, North America, and Oceania. Based on our examination of existing data, the current literature does not support the notion that HPV is a prominent carcinogen in ESCC. We conclude that there is no basis to change the current clinical approach to ESCC patients with respect to tumor HPV status.

Human papillomavirus shows highly variable prevalence in esophageal squamous cell carcinoma and no significant correlation to p16INK4a overexpression: a systematic review

INTRODUCTION

This review investigates the role of p16(INK4a) as a marker of transcriptionally active human papillomavirus (HPV) in esophageal squamous cell carcinoma (ESCC) and the regional prevalence of HPV in ESCC.

METHODS

PubMed, EMBASE, and the Cochrane Library were systematically searched with the purpose of identifying all studies published between January 1980 and July 2013 reporting both HPV and p16 results in a minimum of five human ESCC specimens.

RESULTS

Twelve studies were identified, providing data on a total of 1383 ESCC specimens collected between 1987 and 2009 from 10 different countries. HPV DNA was detected in 12.0% (n = 161) of 1347 specimens, and p16(INK4a) was detected in 33.9% (n = 209) of 617 specimens. The HPV presence varied from 0% to 70% among the studies. The prevalence of p16(INK4a) overexpression in HPV-positive and HPV-negative specimens demonstrated no statistically significant difference, neither for the combined data (p = 0.7507) nor for any individual study, and detection of p16(INK4a) overexpression did not affect the odds of tumors being HPV positive (odds ratio = 1.0666 with 95% confidence interval 0.7040-1.6157). In a pooled analysis, the sensitivity of p16(INK4a) overexpression as a marker of HPV DNA presence was 0.35, the specificity 0.67, and the positive predictive value 0.25.

CONCLUSIONS

This systematic review reports great regional variation in the prevalence of HPV in ESCC and suggests that p16(INK4a) is not a reliable marker of HPV status in ESCC.

Squamous Cell Carcinoma - Similarities and Differences among Anatomical Sites

Squamous cell carcinoma (SCC) is an epithelial malignancy involving many anatomical sites and is the most common cancer capable of metastatic spread. Development of early diagnosis methods and novel therapeutics are important for prevention and mortality reduction. In this effort, numerous molecular alterations have been described in SCCs. SCCs share many phenotypic and molecular characteristics, but they have not been extensively compared. This article reviews SCC as a disease, including: epidemiology, pathology, risk factors, molecular characteristics, prognostic markers, targeted therapy, and a new approach to studying SCCs. Through this comparison, several themes are apparent. For example, HPV infection is a common risk factor among the four major SCCs (NMSC, HNSC, ESCC, and NSCLC) and molecular abnormalities in cell-cycle regulation and signal transduction predominate. These data reveal that the molecular insights, new markers, and drug targets discovered in individual SCCs may shed light on this type of cancer as a whole.

The absence of human papillomavirus in esophageal squamous cell carcinoma in East China

Esophageal squamous cell carcinoma (ESCC) is one of the most common types of tumors worldwide, particularly in China, and human papillomavirus (HPV) is thought to be a potential risk factor for this cancer. To determine whether this is true, we collected 177 formalin-fixed and paraffin-embedded ESCC samples from two hospitals. We screened for 23 different HPV genotypes using a human papillomavirus genotyping kit, which allowed us to amplify the L1 gene by polymerase chain reaction (PCR) and test for 23 HPV subtypes by reverse dot blot (RDB) on a single membrane. We also used immunohistochemistry (IHC) to detect the P16(INK4a) protein, the expression of which is linked to HPV E7 activity and which is used to diagnose cervical intraepithelial neoplasia. The genotyping results showed that only six samples were weakly positive for HPV: two for HPV16, two for HPV11 and two for HPV35, with no samples showing strong positive signals. The IHC results showed only five samples with diffuse positive staining, with the other samples being completely negative or having only focal positive signals, which were considered as negative. This study demonstrates that the HPV infection rate in ESCC samples is very low, suggesting that HPV is not the etiological cause of ESCC.

Association between human papillomavirus (HPV) and oesophageal squamous cell carcinoma: a meta-analysis

SUMMARY

The oncogenic potential of human papillomaviruses (HPV) is well known in the context of cervical carcinoma; however, their role in the development of oesophageal squamous cell carcinoma (OSCC) is less clear. We aimed to determine the extent of the association between HPV infection and OSCC. A comprehensive literature search found 132 studies addressing HPV and OSCC in human cases, and a meta-analysis was performed using a random-effects model. There was evidence of an increased risk of OSCC in patients with HPV infection [odds ratio (OR) 2·69, 95% confidence interval (CI) 2·05-3·54]. The prevalence of HPV in OSCC was found to be 24·8%. There was an increased risk associated with HPV-16 infection (OR 2·35, 95% CI 1·73-3·19). Subgroup analyses showed geographical variance, with Asia (OR 2·94, 95% CI 2·16-4·00), and particularly China (OR 2·85, 95% CI 2·05-3·96) being high-risk areas. Our results confirm an increase in HPV infection in OSCC cases.

Prevalence of human papillomavirus among oesophageal squamous cell carcinoma cases: systematic review and meta-analysis

Background:

Oncogenic human papillomavirus (HPV) has been hypothesised as a risk factor for oesophageal squamous cell carcinoma (OSCC), but aetiological research has been limited by the varying methodology used for establishing HPV prevalence. The aims of this systematic review and meta-analysis were to estimate the prevalence of HPV DNA detected in OSCC tumours and the influence of study characteristics.

Methods:

Study-level estimates of overall and type-specific HPV prevalence were meta-analysed to obtain random-effects summary estimates.

Results:

This analysis included 124 studies with a total of 13 832 OSCC cases. The average HPV prevalence (95% confidence interval) among OSCC cases was 0.277 (0.234, 0.320) by polymerase chain reaction; 0.243 (0.159, 0.326) by in situ hybridisation; 0.304 (0.185, 0.423) by immunohistochemistry; 0.322 (0.154, 0.490) by L1 serology; and 0.176 (0.061, 0.292) by Southern/slot/dot blot. The highest HPV prevalence was found in Africa and Asia, notably among Chinese studies from provinces with high OSCC incidence rates.

Conclusions:

Future research should focus on quantifying HPV in OSCC cases using strict quality control measures, as well as determining the association between HPV and OSCC incidence by conducting large, population-based case–control studies. Such studies will provide a richer understanding of the role of HPV in OSCC aetiology.

Systematic review with meta-analysis: the association between human papillomavirus infection and oesophageal cancer

BACKGROUND

Human papillomavirus (HPV) infection might be one of the potential risk factors for oesophageal cancer. However, the previous epidemiological findings were heterogeneous.

AIM

To explore the association between HPV infection and oesophageal cancer risk by means of meta-analysis.

METHODS

Studies on HPV infection and oesophageal cancer were identified, the prevalence of HPV infection and its association with oesophageal cancer risk were quantitatively summarised by meta-analysis.

RESULTS

A total of 8990 oesophageal squamous cell carcinoma (SCC) patients and 174 oesophageal adenocarcinomas patients were evaluated from 76 included studies. Summarised HPV prevalence in oesophageal SCC was 22.2% [95% confidence interval (CI), 18.3-26.7%], HPV-16 was the most frequently observed subtype with a summarised prevalence of 11.4% (95% CI: 8.2-15.7%). With respect to oesophageal adenocarcinoma, HPV prevalence was 35.0% (95% CI, 13.2-65.7%) and HPV-16 prevalence was 11.4% (95% CI: 8.2-15.7%). Due to the limited number of included studies on oesophageal adenocarcinoma, association analyses were performed to oesophageal SCC only. Significant association was observed between HPV infection and oesophageal SCC with a summarised odds ratio of 3.32 (95% CI, 2.26-4.87). According to HPV-16, the strength of the association was found to be 3.52 (95% CI, 2.04-6.07).

CONCLUSIONS

Human papillomavirus infection was observed to be associated with an increased risk of oesophageal SCC in this meta-analysis. However, due to the evident heterogeneity observed between the included studies and the strength of the association not as strong as observed for cervical cancer and laryngeal cancer, further studies are needed to clarify the relation and its underlying mechanisms.

Heterozygote of PLCE1 rs2274223 increases susceptibility to human papillomavirus infection in patients with esophageal carcinoma among the Kazakh populations

The involvement of human papillomavirus (HPV) in the carcinogenesis of esophageal squamous carcinoma remains undetermined. However, three genome-wide association studies of esophageal cancer have identified a shared susceptibility locus at 10q23 (rs2274223: A5780G) in phospholipase C epsilon 1 (PLCE1). The current study aims to present a comprehensive and novel spectrum about the HPV genotype distribution of esophageal carcinoma in Kazakhs and assess its association with PLCE1 polymorphisms. The HPV genotypes in 183 patients with esophageal cancer and 89 controls selected from the Kazakh population were evaluated using the HPV gene chip. The PLCE1 rs2274223 variant was genotyped in esophageal carcinoma patients by MALDI-ToF Mass Spectrometry. The presence of seven HPV genotypes in esophageal carcinoma tissues-including HPV 16, 18, 35, 52, 6, 11, 43-was significantly higher at 31.7% than those in controls at 9.0% (P < 0.001). Such presence was strongly associated with increased risk of esophageal carcinoma (OR 4.70; 95% CI 2.13-10.36). Among all HPV genotypes detected, HPV16 was the most common genotype identified (29.0%, OR 4.13; 95% CI 1.87-9.13), which is significantly associated with well-differentiated esophageal carcinoma (P = 0.037). HPV-positive patients were generally younger than HPV-negative patients (70.1% vs. 29.3%, P = 0.013). PLCE1 rs2274223 genotypes AG and AG/GG were significantly associated with HPV-positive patients with esophageal carcinoma (OR 2.05, 95% CI 1.03-4.08 and OR 1.98, 95% CI 1.02-3.84, respectively). These findings suggest that heterozygote of PLCE1 rs2274223 increases susceptibility to HPV infection in patients with esophageal carcinoma among the Kazakh populations.

Human papillomavirus was not detected by PCR using multiple consensus primer sets in esophageal adenocarcinomas in Chinese patients

The role of human papillomavirus (HPV) infection in the development of esophageal squamous cell carcinoma is well established; however, there are few reports on the role of HPV in esophageal adenocarcinoma. To evaluate the putative role of HPV infection in esophageal adenocarcinoma, 57 formalin-fixed, paraffin-embedded esophageal adenocarcinoma specimens were collected from four hospitals in Shanghai and Anyang, China, between 1999 and 2008. HPV DNA was analyzed using PCR with multiple sets of consensus primers for HPV, GP5+/6+, CPI/CPIIG, SPF10, pU-1M/pU2R, and pU31B/pU2R. Glyceraldehyde-3-phosphate dehydrogenase (GAPDH), the internal control, was amplified successfully in all 57 specimens. However, HPV amplification was not detected in any specimens with any of the consensus primer sets used. The present study indicates that HPV infection is not likely to be a major factor in the etiology of esophageal adenocarcinoma in the Chinese population.

Human papillomavirus types 16 and 18 in esophagus squamous cell carcinoma: a meta-analysis

PURPOSE

A possible carcinogenic role of human papillomavirus (HPV) has been investigated in esophageal squamous cell carcinoma (ESCC) for nearly 30 years with mixed results. We performed a meta-analysis to assess the prevalence of "high-risk" HPV, HPV-16/18, in this disease. We also evaluated the association between infection with HPV-16/18 and ESCC risk by meta-analysis of case-control studies.

METHODS

Eligible studies published up to September 30, 2012 were retrieved via both computer searches of MEDLINE and EMBASE and manual review of references. A random-effects model was used to calculate summary prevalence and odds ratios (ORs) and corresponding 95% confidence intervals (CIs).

RESULTS

A total of 5755 cases of ESCC from 68 studies were included in this meta-analysis. Overall, 11.67% (95% CI, 7.74%-16.21%) of ESCC cases harbored HPV-16 and 1.82% (95% CI, 0.90%-2.95%) harbored HPV-18. In addition, meta-analysis of 10 case-control studies showed a significant increase in ESCC risk with HPV-16 infection (summary ORs = 3.55; 95% CIs, 2.05%-6.14%). However, this increased risk in ESCC was not made for HPV-18 infection (summary ORs = 1.25; 95% CIs, 0.46%-3.43%).

CONCLUSIONS

This meta-analysis indicated that HPV-16 and -18 can be detected in ESCC. HPV-16, but not HPV-18, is significantly associated with the risk of ESCC. However, it is early to conclude that both types of HPV are involved in esophageal carcinogenesis.

Human papillomavirus and the risk of Barrett's esophagus

Human papillomavirus (HPV) is strongly associated with squamous esophageal cancer. The potential role of HPV in Barrett's esophagus (BE) has been examined but remains unclear. The aim of the study was to determine the prevalence of HPV in esophageal and gastric tissues obtained from patients with and without BE. We designed a cross-sectional study was conducted with prospective enrollment of eligible patients scheduled for esophagogastroduodenoscopy (EGD). All participants had biopsies of endoscopic BE, squamous-lined esophagus, and stomach. Immunohistochemistry (IHC) on formalin-fixed and paraffin-embedded tissue was conducted using monoclonal antibodies. Polymerase chain reaction (PCR) for HPV was performed on DNA extracted from esophageal biopsies snapped frozen within 30 minutes after endoscopic capture. The Roche HPV Linear Array Assay with PGMY primers that has high sensitivity for detecting 37 types of HPV was used. A total of 127 subjects were included: 39 with definitive BE had IHC done on samples from non-dysplastic BE, squamous esophagus, gastric cardia, and gastric body; and 88 control patients without BE had IHC done on squamous esophageal samples, gastric cardia, and gastric body. HPV was not detected in any of the samples in either group. For confirmation, HPV DNA PCR was performed on randomly selected samples from 66 patients (both esophagus and BE from 13 patients with BE, and 53 esophagus from patients without BE); no sample had HPV DNA detected via PCR in the presence of adequate quality control. HPV infection does not play a role in the formation of non-dysplastic Barrett's esophagus in men in the United States.

The role of inflammation in HPV infection of the Oesophagus

BACKGROUND

Several human cancers are known to be associated with inflammation and/or viral infections. However, the influence of tumour-related inflammation on viral uptake is largely unknown. In this study we used oesophageal squamous cell carcinoma (OSCC) as a model system since this type of cancer is associated with chronic irritation, inflammation and viral infections. Although still debated, the most important viral infection seems to be with Human Papillomavirus (HPV). The present study focused on a possible correlation between inflammation, OSCC development and the influence of HPV infection.

METHODS

A total of 114 OSCC biopsies and corresponding normal tissue were collected at Groote Schuur Hospital and Tygerberg Hospital, Cape Town (South Africa), that were subjected to RNA and DNA isolation. RNA samples were analysed by quantitative Light Cycler RT-PCR for the expression of selected genes involved in inflammation and infection, while conventional PCR was performed on the DNA samples to assess the presence of integrated viral DNA. Further, an in vitro infection assay using HPV pseudovirions was established to study the influence of inflammation on viral infectivity using selected cell lines.

RESULTS

HPV DNA was found in about 9% of OSCC patients, comprising predominantly the oncogenic type HPV18. The inflammatory markers IL6 and IL8 as well as the potential HPV receptor ITGA6 were significantly elevated while IL12A was downregulated in the tumour tissues. However, none of these genes were expressed in a virus-dependent manner. When inflammation was mimicked with various inflammatory stimulants such as benzo-α-pyrene, lipopolysaccharide and peptidoglycan in oesophageal epithelial cell lines in vitro, HPV18 pseudovirion uptake was enhanced only in the benzo-α-pyrene treated cells. Interestingly, HPV pseudovirion infectivity was independent of the presence of the ITGA6 receptor on the surface of the tested cells.

CONCLUSION

This study showed that although the carcinogen benzo-α-pyrene facilitated HPV pseudovirion uptake into cells in culture, HPV infectivity was independent of inflammation and seems to play only a minor role in oesophageal cancer.

Incidence of human papilloma virus in esophageal squamous cell carcinoma in patients from the Lublin region

AIM: To assess the prevalence of human papilloma virus (HPV) in esophageal squamous cell carcinoma (ESCC) in the south-eastern region of Poland.

METHODS: The study population consisted of 56 ESCC patients and 35 controls. The controls were patients referred to our department due to other non-esophageal and non-oncological disorders with no gross or microscopic esophageal pathology as confirmed by endoscopy and histopathology. In the ESCC patients, samples were taken from normal mucosa (56 mucosa samples) and from the tumor (56 tumor samples). Tissue samples from the controls were taken from normal mucosa of the middle esophagus (35 control samples). Quantitative determination of DNA was carried out using a spectrophotometric method. Genomic DNA was isolated using the QIAamp DNA Midi Kit. HPV infection was identified following PCR amplification of the HPV gene sequence, using primers MY09 and MY11 complementary to the genome sequence of at least 33 types of HPV. The sequencing results were computationally analyzed using the basic local alignment search tool database.

RESULTS: In tumor samples, HPV DNA was identified in 28 of 56 patients (50%). High risk HPV phenotypes (16 or/and 18) were found in 5 of 56 patients (8.9%), low risk in 19 of 56 patients (33.9%) and other types of HPV (37, 81, 97, CP6108) in 4 of 56 patients (7.1%). In mucosa samples, HPV DNA was isolated in 21 of 56 patients (37.5%). High risk HPV DNA was confirmed in 3 of 56 patients (5.3%), low risk HPV DNA in 12 of 56 patients (21.4%), and other types of HPV in 6 of 56 patients (10.7%). In control samples, HPV DNA was identified in 4 of 35 patients (11.4%) with no high risk HPV. The occurrence of HPV in ESCC patients was significantly higher than in the controls [28 of 56 (50%) vs 4 of 35 (11.4%), P < 0.001]. In esophageal cancer patients, both in tumor and mucosa samples, the predominant HPV phenotypes were low risk HPV, isolated 4 times more frequently than high risk phenotypes [19 of 56 (33.9%) vs 5 of 56 (8.9%), P < 0.001]. A higher prevalence of HPV was identified in female patients (71.4% vs 46.9%). Accordingly, the high risk phenotypes were isolated more frequently in female patients and this difference reached statistical significance [3 of 7 (42.9%) vs 2 of 49 (4.1%), P < 0.05]. Of the pathological characteristics, only an infiltrative pattern of macroscopic tumor type significantly correlated with the presence of HPV DNA in ESCC samples [20 of 27 (74.1%) vs 8 of 29 (27.6%) for ulcerative or protruding macroscopic type, P < 0.05]. The occurrence of total HPV DNA and both HPV high or low risk phenotypes did not significantly differ with regard to particular grades of cellular differentiation, phases in depth of tumor infiltration, grades of nodal involvement and stages of tumor progression.

CONCLUSION: Low risk HPV phenotypes could be one of the co-activators or/and co-carcinogens in complex, progressive, multifactorial and multistep esophageal carcinogenesis.

Role of human papillomaviruses in esophageal squamous cell carcinoma

Esophageal cancer (EC) is responsible for almost half a million deaths worldwide annually and has a multifactorial etiology, which may account for its geographical variation in incidence. In the last 30 years the potential of human papillomaviruses (HPV) as oncogenes or co-factors in the tumorigenic process of esophageal squamous cell carcinoma (ESCC) has been widely studied. While the etiology of HPV in cervical and certain other anogenital and aerodigestive cancers has been established, results regarding its role in EC have been largely inconclusive. A causal association can be evaluated only with a case-control study, where normal controls are compared to ESCC cases for the presence of HPV. We reviewed all studies investigating ESCC tissue for HPV DNA and identified 139 that met our inclusion criteria, of which only 22 were case-control studies. Our results support previous findings of higher levels of HPV detection in high-risk ESCC regions than in areas of low risk. In addition, we confirm that the role of HPV in ESCC remains unclear, despite an accumulation of studies on the subject. The variations in investigative technique, study design and sample types tested may account for the lack of consistency in results. There is a need for a meta-analysis of all case-control studies to date, and for large, well-designed case-control studies with adequate power to investigate the association. The potential benefits of prophylactic HPV vaccines could be evaluated if HPV is identified as an etiological factor in EC, highlighting the need for further research in this area.

Geographic origin is a significant determinant of human papillomavirus prevalence in oesophageal squamous cell carcinoma: systematic review and meta-analysis

BACKGROUND

Since the first reports in 1982 suggesting an aetiological role for human papillomavirus (HPV) in a subset of oesophageal squamous cell carcinomas (ESCC), the literature reporting HPV detection in ESCC has expanded rapidly. However no formal meta-analysis of this literature has been published yet. The objective of this study was to perform a systematic review and formal meta-analysis of the literature reporting HPV detection in ESCC.

METHODS

MEDLINE and Current Contents were searched through March 2012. The effect size was calculated as event rates and their 95% confidence interval (95% CI), with homogeneity testing using Cochran's Q and I² statistics. Meta-regression was used to test the impact of study-level covariates (HPV detection method, geographic origin of study) on effect size, and potential publication bias was estimated using funnel plot symmetry (Begg and Mazumdar rank correlation, Egger's regression, and Duval and Tweedie's trim and fill method).

RESULTS

Of the 1177 abstracts found, 152 studies were determined to be eligible for this meta-analysis. These 152 studies covered a total of 10,234 ESCC cases, analysed by different HPV detection methods in different geographic regions. Of these 10,234 cases, 3135 (30.6%) tested HPV-positive, translating to an effect size of 0.372 (95% CI 0.360-0.384; fixed effects model) and 0.290 (95% CI 0.251-0.31; random effects model). When stratified by HPV detection technique, there was a significant heterogeneity between the studies, but importantly, the between-strata summary comparison was not significant (random effects model; p = 0.440). In contrast, there was significant heterogeneity between the studies from the different geographic regions. In the maximum likelihood meta-regression, HPV detection method was not a significant study-level covariate, in contrast to the geographic origin of the study, which had a significant impact (p = 0.00005) on the summary effect size estimates. No evidence for significant publication bias was found in funnel plot symmetry testing. In the sensitivity analysis, all meta-analytic results appeared robust to all (n = 151) one-by-one study removals.

CONCLUSIONS

These meta-analysis results indicate that the reported wide variability in HPV detection rates in ESCC is not due to the HPV detection techniques, but is explained by the geographic origin of the study. These data substantiate the recently elaborated concept that ESCC might have a different aetiology in low-incidence and high-incidence geographic regions, HPV playing an important role only in the latter.

High-risk human papillomavirus in esophageal squamous cell carcinoma

BACKGROUND

Although most cases of esophageal squamous cell carcinoma (ESCC) in western populations have been attributed to high levels of exposure to tobacco and alcohol, infectious agents have been postulated as possible causes, particularly human papillomavirus (HPV).

METHODS

To explore this issue, we analyzed HPV DNA prevalence and HPV types together with lifestyle factors, in relation to tumor stage and survival in a low-incidence population. Archived tumor samples from a nationwide cohort of 222 ESCC patients were tested for the presence of HPV DNA by PCR; positive samples were sequenced to determine HPV type, and p16(INK4a) status was assessed by immunohistochemistry.

RESULTS

Of 222 ESCC patients, 8 tested HPV positive (prevalence, 3.6%; 95% confidence interval, 1.1-6.1%), of which 6 were HPV-16 positive and 2 were HPV-35 positive. Four of the eight HPV-positive tumors overexpressed p16(INK4a). None of 55 normal esophageal tissue samples from healthy participants had any detectable HPV. Although the numbers were low, it seemed that patients with HPV-positive ESCC tumors were younger than those with HPV-negative tumors (mean age, 60.8 versus 65.3 years, P = 0.18) and had higher body mass index (BMI) throughout life (mean current BMI of 25.1 for HPV positive, 22.2 for HPV negative, P = 0.08; mean BMI at 20 years of 25.8 for HPV positive, 22.1 for HPV negative, P = 0.003). We found no difference between patients with HPV-positive and HPV-negative tumors with respect to other lifestyle factors.

CONCLUSIONS

These findings suggest a very low prevalence of HPV DNA in human ESCC.

IMPACT

HPV is very unlikely to be a common cause of ESCC in Australia.

Assessment of immunohistochemistry for p16INK4 and high-risk HPV DNA by in situ hybridization in esophageal squamous cell carcinoma

The role of high-risk human papillomavirus (HPV) in the pathogenesis of esophageal squamous cell carcinoma (ESCC) remains unclear. p16(INK4) is used as a surrogate marker to detect HPV-related tumors but has had discrepant results in ESCC. In this study, 32 cases of ESCC were examined to determine the relationship between p16(INK4) expression and high-risk HPV. All the tumors were stained by immunohistochemistry for p16(INK4). Tumors having p16(INK4) nuclear and/or nuclear and cytoplasmic expression were considered positive. Tumors positive for p16(INK4) expression were tested for high-risk HPV by in situ hybridization (ISH). In all, 20 cases of ESCC (63%) showed only cytoplasmic staining for p16(INK4), and 11 cases (34%) showed both cytoplasmic and nuclear staining for p16(INK4); 4 cases (13%) showed no staining for p16(INK4). None of the p16(INK4) -positive cases were positive for high-risk HPV by ISH. These results indicate that p16(INK4) expression in ESCC does not correlate with the presence of high-risk HPV DNA by ISH. High-risk HPV does not seem to play a major role in the carcinogenesis of ESCC in low-risk areas.

Northwestern China: a place to learn more on oesophageal cancer. Part one: behavioural and environmental risk factors

Oesophageal squamous cell carcinoma (OSCC) remains a public health problem in many countries, especially in emerging and developing countries. Epidemiology of OSCC is characterized by marked differences in prevalence between countries/regions/ethnical groups. The highest incidence in the world is reached by populations living in specific areas of northwestern Xinjiang, China where age-adjusted mortality may reach 150 of 100 000. In fact, there are also marked differences among the various geographical areas and the various ethnic groups within the region, which suggests specific risk factors. Behavioural factors include those factors which are common to all 'high-risk populations', such as tobacco smoking and alcohol drinking. However, the very unusual sex ratio (1.2 : 1.0) and young age range of OSCC occurrence suggests the involvement of additional early risk factors shared by males and females, and which are different from those studied in other 'high-risk' areas of the world, including China, such as LinXian area. These include drinking very hot and salted tea, boiled with milk; a diet rich in meat, especially salted, dry and/or smoked meat, and dairy products; and a diet poor in fresh fruit and vegetables. The combination of hot drinks (such as milk, tea and soups) and high-degree spirit drinks, and hard food (bread, meat and cheese), together with poor oral hygiene and tooth loss, is likely to add mechanical injury of the oesophagus to other factors linked to climate characteristics of the area (drought) and dietary habits, which promote a sodium and nitrosamine-rich diet. Association of early and severe hypertension in the same populations at high risk of OSCC might likely raise more attention. Human papilloma virus (HPV) infection, and especially HPV 16/18 E6/E7, with gene mutations and association with p53 overexpression, may contribute to the extremely high incidence of OSCC observed in Xinjiang, and could be accessible to prevention. Infection may especially be a crucial additional factor in the Uygur population in which not only HPV infection but also infection with other oncogenic viruses, such as HHV8, are highly prevalent. Genetic polymorphism might interact with viruses and/or viral products to promote carcinogenesis. These observations in northwestern China suggest that usually neglected factors, such as sodium excess and viral infection, could be taken into more account when studying OSCC risk factors in other parts of the world, especially Europe.

Vaccination against human papilloma virus (HPV): epidemiological evidence of HPV in non-genital cancers

Recently, the vaccine against human papillomavirus (HPV) was introduced in the national vaccination programmes of several countries worldwide. The established association between HPV and the progression of cervical neoplasia provides evidence of the expected protection of the vaccine against cervical cancer. During the last two decades several studies have also examined the possible involvement of HPV in non-genital cancers and have proposed the presence of HPV in oesophageal, laryngeal, oropharyngeal, lung, urothelial, breast and colon cancers. The possible involvement of HPV in these types of cancer would necessitate the introduction of the vaccine in both boys and girls. However, the role of HPV in the pathogenesis of these types of cancer has yet to be proven. Moreover, the controversial evidence of the possible impact of the vaccination against HPV in the prevention of non-genital cancers needs to be further evaluated. In this review, we present an overview of the existing epidemiological evidence regarding the detection of HPV in non-genital cancers.

Human papilloma virus and esophageal carcinoma in a Latin-American region

AIM: To investigate the presence of high-risk human papilloma virus (HPV) in esophageal squamous cell carcinomas (ESCCs) in a non-selected Mexican population.

METHODS: Cases with a pathological diagnosis of squamous cell carcinoma of the esophagus were obtained from Department of Pathology files, at the National Cancer Institute in Mexico City during the period between 2000 and 2008. Slides from each case were reviewed and cases with sufficient neoplastic tissue were selected for molecular analysis. DNA was extracted from paraffin-embedded tissue samples for polymerase chain reaction analysis to detect HPV DNA sequences. Demographic and clinical data of each patient were retrieved from corresponding clinical records.

RESULTS: HPV was detected in 15 (25%) of ESCCs. HPV-16 was the most frequently observed genotype, followed by HPV-18; HPV-59 was also detected in one case. Unfortunately, HPV genotype could not be established in three cases due to lack of material for direct sequencing, although universal primers detected the presence of HPV generic sequences. No low-risk HPV genotypes were found nor was HPV-16/18 co-infection. HPV presence in ESCC was not significantly associated with gender, age, alcohol consumption, smoking, anatomic location, or histologic grade. All patients belonged to low and very low socioeconomic strata, and were diagnosed at advanced disease stage. Male patients were most commonly affected and the male:female ratio in HPV-positive ESCC increased two-fold in comparison with HPV-negative cases (6.5:1 vs 3.1:1).

CONCLUSION: High prevalence of high-risk HPV in ESCC in Mexico does not support the hypothesis that HPV-associated ESCC is more common in areas with higher ESCC incidence rates.

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.

Risk factors and gene expression in esophageal cancer

Esophageal cancer is a significant worldwide health problem because of its poor prognosis and high incidence in certain parts of the world. Tobacco smoke and alcohol consumption are significant risk factors for esophageal squamous cell carcinoma, whereas frequent gastroesophageal reflux and subsequent inflammatory reactions play a role in causing the adenocarcinoma. Esophageal carcinogenesis involves multiple genetic alterations. A large body of knowledge has been generated regarding molecular alterations associated with esophageal carcinogenesis. These alterations include aberrant cell cycle control, DNA repair, cellular enzymes, growth factor receptors, and nuclear receptors. This chapter reviews the most frequent gene alterations and their correlation with risk factors as well as the prevention strategies in esophageal cancer.

Human papillomavirus in high- and low-risk areas of oesophageal squamous cell carcinoma in China

To examine the potential roles of human papillomavirus (HPV) in oesophageal squamous cell carcinoma (ESCC) development, we examined the presence of HPV DNA in paraffin-embedded ESCC tissues collected from two areas with different ESCC incidence rates in China, that is, Gansu (n=26) and Shandong (n=33), using PCR with SPF10 primers, or PCR with GP5+/GP6+ primers combined with Southern blot hybridisation. HPV genotype was determined by the INNO-LiPA HPV genotyping kit. HPV DNA was detected in 17 cases (65%) in Gansu, where ESCC incidence is much higher than in Shandong, where HPV was positive in two samples (6%). HPV genotypes 16 and 18 were detected in 79 and 16% of HPV-positive samples, respectively. Real-time PCR analysis suggested the presence of integrated form of HPV DNA in all the HPV-16-positive samples, but its viral load was estimated to be only <1–2 copies cell⁻¹. We could not detect HPV 16/18 E6 protein expression by immunostaining in any of the HPV-16-positive samples. Neither p16^INK4a nor p53 expression was related to HPV presence in ESCCs. Further studies seem warranted to examine the possible aetiological roles of HPV in ESCC.