Human papillomavirus involvement in esophageal carcinogenesis in the high-incidence area of China. A study of 700 cases by screening and type-specific in situ hybridization

Study to investigate the prevalence of human papillomavirus in Barrett's oesophagus using a novel screening methodology

Introduction

Human papillomavirus (HPV) is strongly associated with Barrett’s dysplasia and oesophageal cancer suggesting a role in carcinogenesis. HPV persistence predicts treatment failure after endotherapy for Barrett’s dysplasia. This pilot study applies a novel HPV screening tool (previously only used in the oropharynx) to detect HPV DNA directly and determine the prevalence rates in Barrett’s oesophagus (BO).

Method

DNA was extracted from 20 formalin-fixed BO samples. HPV DNA was detected using real-time PCR and gel electrophoresis.

Results

5 out of 20 patients were identified as positive for HPV. Prevalence was 25% in patients with BO.

Conclusion

This method can be used in BO’s tissue to determine HPV infection. Adoption of this as a screening test could potentially revolutionise future research in this area. If a clear link between HPV and Barrett’s dysplasia can be confirmed, this qPCR method has the potential to aid in monitoring and/or dysplasia detection by stratifying those most at risk and aid in the development of new therapies.

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.

HPV, KRAS mutations, alcohol consumption and tobacco smoking effects on esophageal squamous-cell carcinoma carcinogenesis

Esophageal squamous-cell carcinoma (ESCC) is an invasive neoplastic disease generally associated with poor survival rates. The incidence of ESCC is characterized by marked geographic variation, with highest rates noted in developing Southeastern African, Central and Eastern Asian countries. In the developed Western European and North American regions where there is a low disease incidence, heavy alcohol and cigarette consumption constitute major risk factors. The toxic effects of both these risk factors cause chronic irritation and inflammation of the esophageal mucosa, while at the cellular level they further confer mutagenic effects by the activation of oncogenes (e.g., RAS mutations), inhibition of tumor-suppressor genes, and profound DNA damage. Viral infections, particularly with human papillomavirus, may activate specific antiapoptotic, proliferative and malignant cellular responses that may be intensified in combination with the effects of alcohol and tobacco. In countries with a high ESCC incidence, low socioeconomic status and an inadequate diet of poorly preserved food are combined with basic nutritional deficiencies and inadequate medical treatment. These conditions are favorable to the above-mentioned risk factors implicated in ESCC development, which may be present and/or habitually used in certain populations. New perspectives in epidemiological studies of ESCC development and its risk factors allow genome-wide research involving specific environments and habits. Such research should consist of adequately large and representative samples, should use newly designed informative genetic markers, and apply genomic variation analysis of the functional transcripts involved in malignant cell cycle regulation and neoplastic transformation in the multi-step process of ESCC carcinogenesis.

Evaluation of the Prevalence of Human Papillomavirus and Epstein-Barr Virus in Esophageal Squamous Cell Carcinomas

The aim of this study was to determine the possible involvement of human papillomavirus and Epstein-Barr virus in esophageal squamous cell cancer (ESCC) carcinogenesis in the Greek population. DNA was extracted from 30 ESCC and 27 normal esophageal specimens and screened for HPV type-specific or EBV infection by PCR-based assay. Seventeen out of 30 ESCC specimens (56%) were found positive for HPV DNA, of which 15 (88%) were typed as HPV-18 infected, one (5.9%) as HPV-16 infected, and one (5.9%) as infected by an HPV type different from the studied HPV-6, 11, 16, 18 and 33 subtypes. Six of the 27 normal esophageal specimens (22.2%) were positive for HPV infection, five typed as HPV-18 (83.3%) and one as HPV-16 (16.7%). All samples were negative for EBV genome detection as assessed by the PCR assay. No statistically significant correlation was found between the HPV status of the tumor samples and clinical parameters including sex, age of the patients, tobacco or alcohol use, differentiation grade of the lesions and stage of the disease. In conclusion, our findings indicate a statistically significant (p<0.001) overall association between ESCC and HPV infection, mostly related to the HPV-18 subtype, in the Greek population.

A Meta-Analysis and Systematic Review on the Association between Human Papillomavirus (Types 16 and 18) Infection and Esophageal Cancer Worldwide

BACKGROUND

Esophageal cancer is a common and aggressive malignant tumor. This study aimed to investigate the association between human papillomavirus (HPV) Types 16 and 18 and esophageal carcinoma (EC) in the world population by conducting a meta-analysis.

MATERIALS AND METHODS

Computerized bibliographic and manual searches were performed to identify all eligible literatures between 1982 and 2014. PUBMED (http://www.ncbi.nlm.nih.gov/pubmed/) and CNKI (http://www.cnki.net/) were the primary sources of case-control studies, and key words used include human papillomavirus, HPV, esophageal, esophagus, cancer, carcinoma, and tumor. All searches were performed by reviewing articles and abstracts cited in the published systematic reviews and case-control studies. Prospective studies that reported relative risk (RR) estimates with 95% CIs for the association between HPV and EC were included.

RESULTS

Thirty-three randomized studies were identified, and the main features of these trials were included in this systematic review. HPV infection rate in the EC group was 46.5%, while HPV infection rate in the control group was 26.2% (OR = 1.62; 95% CI, 1.33-1.98). In China, the merger OR value was 1.62 (95% CI: 1.26-2.07); while in the Asian region, the merger OR value was 1.63 (95% CI: 1.29-2.04). There were statistical differences in HPV testing due to different detection methods such as PCR, IHC and ISH. In the PCR detection group, the merger OR value was 1.61 (95% CI: 1.33-1.95).

CONCLUSIONS

These results indicate that HPV infection and the incidence of EC are closely associated.

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.

Detection of human papillomavirus in esophageal and gastroesophageal junction tumors: A retrospective study by real-time polymerase chain reaction in an instutional experience from Turkey and review of literature

Esophageal cancer is a poor-prognosis malignancy that ranks eighth among all cancer types, and its prevalence shows differences among geographical regions. Although the most important risk factors for esophageal carcinoma are alcohol and smoking, viral infections, particularly HPV infection, are also considered among etiological agents. Our study aims to detect the presence of HPV in esophageal cancers in our patient population and to investigate its correlation with clinico-pathological parameters. We investigated the presence of HPV-DNA by real-time polymerase chain reaction in a total of 52 patients with esophageal cancer. Subtype analysis was performed in positive cases and was correlated with selected clinico-pathological parameters. Five (9.6%) of 52 tumor samples, 3 squamous cell carcinomas (3/33 cases) and 2 adenocarcinomas (2/19 cases), were HPV-DNA-positive. Subtype analysis could be performed in four HPV-DNA-positive cases, of which three were HPV type-39 and 1 was type-16. The Marmara region, where the present study was carried out, is a region with low-moderate risk for esophageal cancer, and the prevalence of HPV-DNA in these tumors is similar to the prevalence of HPV-DNA reported in the literature for regions with similar risk. In conclusion, we detected HPV DNA in a subset of esophageal and gastroesophageal junction tumors. HPV infection may have a role in esophageal carcinogenesis and high-risk HPV subtypes can particularly be considered among risk factors since the prevalence of high risk HPV infection has also been found to be increased in regions with a high risk for esophageal cancer compared to low-moderate risk regions.

[HPV (Human Papilloma Virus) implication in other cancers than gynaecological]

Worldwide, approximately 5 to 10% of the population is infected by a Human Papilloma Virus (HPV). Some of these viruses, with a high oncogenic risk (HPV HR), are responsible for about 5% of cancer. It is now accepted that almost all carcinomas of the cervix and the vulva are due to an HPV HR (HPV16 and 18) infection. However, these viruses are known to be involved in the carcinogenesis of many other cancers (head and neck [SCCHN], penis, anus). For head and neck cancer, HPV infection is considered as a good prognostic factor. The role of HPV HR in anal cancer is also extensively studied in high-risk patient's population. The role of HPV infection in the carcinogenesis of esophageal, bladder, lung, breast or skin cancers is still debated. Given the multiple possible locations of HPV HR infection, the question of optimizing the management of patients with a HPV+ cancer arises in the implementation of a comprehensive clinical and biological monitoring. It is the same in therapeutics with the existence of a preventive vaccination, for example.

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.

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.

Prevalence of human papillomavirus infection in esophageal and cervical cancers in the high incidence area for the two diseases from 2007 to 2009 in Linzhou of Henan Province, Northern China

The etiological role of human papillomavirus (HPV) in cervical cancer has been well established. However, it is inconclusive whether HPV plays the same role in esophageal carcinogenesis. In this study, we detected HPV infection in 145 frozen esophageal tissues, including 30 normal epithelium (ENOR), 37 dysplasia (DYS) and 78 invasive squamous cell carcinoma (ESCC), and in 143 frozen cervical tissues composed of 30 normal epithelium (CNOR), 38 intraepithelial neoplasia (CIN) and 75 invasive squamous cell carcinoma (CSCC). The patients and symptom-free subjects enrolled in this study were from a high-incidence area for both ESCC and CSCC, Linzhou City, Northern China, from 2007 to 2009. The HPV infection analysis was conducted by using an HPV GenoArray Test Kit. We found that the high-risk HPV types accounted for more than 90 % of the HPV-positive lesions of esophagus and cervix tissues. The prevalence of high-risk HPV types increased significantly during the progression of both esophageal and cervical carcinogenesis (positive rate in esophageal tissues: 33 % ENOR, 70 % in DYS and 69 % in ESCC; positive rate in cervical tissues: 27 % in CNOR, 82 % in CIN and 88 % in CSCC; P < 0.001, respectively). Infection with the high-risk HPV types increased the risk for both DYS and ESCC by 4-fold (DYS vs. ENOR: OR = 4.73, 95 %CI = 1.68-13.32; ESCC vs. ENOR: OR = 4.50, 95 %CI = 1.83-11.05) and increased the risk for both CIN and CSCC by 12-fold and 20-fold (CIN vs. CNOR: OR = 12.18, 95 %CI = 3.85-38.55; CSCC vs. CNOR: OR = 20.17, 95 %CI = 6.93-58.65), respectively. The prevalence of high-risk types in ESCC patients was lower than that in CSCC patients (P = 0.005) and was significantly associated with the degree of ESCC tumor infiltration (P = 0.001). HPV 16 was the most prevalent subtype in both esophageal and cervical tissues. Single HPV infection increased significantly along with the progression of ESCC and maintained a high level in cervical tissues, regardless of whether they were CNOR or CSCC tissues. Our results showed that infection with HPV, especially the high-risk types, was positively associated with both esophageal and cervical cancers, suggesting that HPV also plays a role in the etiology of ESCC in the high-incidence area.

Transcriptionally active human papillomavirus is strongly associated with Barrett's dysplasia and esophageal adenocarcinoma

OBJECTIVES

The role of human papillomavirus (HPV) in Barrett's esophagus (BE) remains unclear. The few studies that have previously investigated HPV and esophageal adenocarcinoma (EAC) or BE have produced either negative data or positive results of doubtful clinical/etiological significance or have detected only low-risk HPV types. We therefore prospectively determined the prevalence of biologically active HPV in esophageal epithelium of patients representing the Barrett's metaplasia-dysplasia-adenocarcinoma sequence.

METHODS

HPV DNA was estimated by nested PCR and viral transcriptional activity detected by E6/7 oncogene mRNA expression and p16INK4A immunohistochemistry in fresh frozen and paraffin-embedded esophageal biopsies of patients with BE, Barrett's dysplasia (BD), and EAC, as well as controls. Biopsies were obtained from the transformation zone (squamocolumnar junction (SCJ)) and the lesion, or corresponding site in controls, i.e., 2 cm above the gastroesophageal junction (GEJ).

RESULTS

Of the 261 patients, 81 were positive for HPV DNA. In controls and BE, the virus was mostly detected at the transformation zone. Compared with controls (18.0%), HPV positivity was significantly more common in BD (68.6%, incidence rate ratio (IRR) 2.94, 95% confidence interval (CI) 1.78-4.85, P<0.001) and EAC (66.7%, IRR 2.87, 95% CI 1.69-4.86, P<0.001), but not in BE (22.1%, IRR 1.06, 95% CI 0.60-1.85, P=0.85). Of the patients, 92.6% were high-risk (HR) HPV, i.e., types 16 and 18. Again, p16INK4A positivity was greatest in BD and EAC and much less in BE patients (44.1%, IRR 17.0 (95% CI 4.86-59.6, P<0.001), 44.4%, 17.0 (95% CI 4.87-59.4, P<0.001), and 10.6%, 3.93 (95% CI 1.01-15.3, P=0.048) respectively). In 66 HPV DNA-positive patients tested for E6/E7 mRNA, none of the control (n=16) or BE (n=13) individuals were positive, whereas 9/22 BD and 9/15 EAC patients demonstrated oncogene expression (P<0.001). When HPV DNA, p16INK4A, and E6/E7 mRNA were all positive, there was a very strong association with disease severity (SCJ: odds ratio (OR) 104, 95% CI 20.3-529, P<0.001; lesion: OR 62.2, 95% CI 12.4-311, P<0.001) than when all were negative.

CONCLUSIONS

Transcriptionally active HR-HPV was strongly associated with BD and EAC, but was largely biologically irrelevant in BE and controls, suggesting a potential role in esophageal carcinogenesis. These data provide robust justification for further detailed longitudinal, interventional, and molecular studies.

The role of human papillomavirus in nongenital cancers

Human papillomavirus (HPV), one of the most common sexually transmitted diseases worldwide, has an established role in the pathogenesis of genital malignancies such as cervical cancer. The virus has also been implicated in the oncogenesis of nongenital cancers including head and neck malignancies (specifically oropharyngeal cancers) as well as anal cancer. There is less clarity regarding its role in lung and esophageal cancers. Worldwide, the incidence and prevalence of HPV-associated oropharyngeal cancer has been increasing over time. These patients have improved outcomes compared with those with HPV-negative oropharyngeal cancers, and there is continued interest in designing treatments specifically for this HPV-positive subgroup. Clinicians continue to gain an understanding of HPV in anal cancers and the risk factors associated with infection and progression to malignancy. This has potential implications for the eventual screening of high-risk groups. While HPV vaccination is currently approved for the prevention of cervical cancer, it also has potential in the prevention of all HPV-associated malignancies. In this review, current understanding of the role of HPV in nongenital cancers is discussed, as well as future implications for treatment and prevention.

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.

Infection and integration of human papillomavirus in esophageal carcinoma

Infection with human papillomavirus (HPV) could be a suspected or potential modifiable risk factor in esophageal carcinoma (EC) but findings have not been consistent. We therefore investigated the epidemiology of HPV infection and integration in the pathogenesis of esophageal carcinoma (EC) in the Shantou region, China. This was a retrospective study involving nested PCR to evaluate HPV presence, HPV genotyping, and analyzing HPV-16 integration status in esophageal tumor tissues (n=106) and paired tumor-adjacent normal tissues, as well as normal esophagus tissue from control subjects (n=100). The detection rates of HPV DNA in EC and tumor-adjacent tissue were significantly higher than that in normal controls (77.4% and 80.2% vs. 33.0%). HPV infection was mainly found in adults, ages 35-47 years old, and the infection rate was negatively associated with the age of EC patients (P-trend<0.05). In addition, the HPV infection rates in patients who smoked was 3.27 times higher than in non-smoking patients (84.9% vs. 67.4%, P<0.05) but was not associated with gender, alcohol consumption, tumor grade or lymph-node metastasis of EC patients. The distribution of HPV genotypes in patients from high to low proportion was HPV-16, -58, -18, -33, -31 and -11. Infection with multiple HPV genotypes mainly included HPV-16/-18 and HPV-16/-33. The integration rate of HPV-16 in EC tissue was higher than that in tumor-adjacent and control tissues (93.4% vs. 50.9% and 45.5%). Our findings indicate that infection with HPV, especially the high-risk HPV, and their integration suggest an association in malignant transformation of EC in the high-incidence EC region in Shantou, China.

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.

No role for human papillomavirus in esophageal squamous cell carcinoma in China

Certain regions of China have high rates of esophageal squamous cell carcinoma (ESCC). Previous studies of human papillomavirus (HPV), a proposed causal factor, have produced highly variable results. We attempted to evaluate HPV and ESCC more definitively using extreme care to prevent DNA contamination. We collected tissue and serum in China from 272 histopathologically-confirmed ESCC cases with rigorous attention to good molecular biology technique. We tested for HPV DNA in fresh-frozen tumor tissue using PCR with PGMY L1 consensus primers and HPV16 and 18 type-specific E6 and E7 primers, and in formalin-fixed paraffin-embedded tumor tissue using SPF(10) L1 primers. In HPV-positive cases, we evaluated p16(INK4a) overexpression and HPV E6/E7 seropositivity as evidence of carcinogenic HPV activity. beta-globin, and thus DNA, was adequate in 98.2% of the frozen tumor tissues (267/272). Of these, 99.6% (95% confidence interval (CI) = 97.9-100.0%) were negative for HPV DNA by PGMY, and 100% (95% CI = 98.6-100%) were negative by HPV16/18 E6/E7 PCR. In the corresponding formalin-fixed paraffin-embedded tumor specimens, 99.3% (95% CI = 97.3-99.9%) were HPV negative by SPF(10). By PGMY, 1 case tested weakly positive for HPV89, a noncancer causing HPV type. By SPF(10), 2 cases tested weakly positive: 1 for HPV16 and 1 for HPV31. No HPV DNA-positive case had evidence of HPV oncogene activity as measured by p16(INK4a) overexpression or E6/E7 seropositivity. This study provides the most definitive evidence to date that HPV is not involved in ESCC carcinogenesis in China. HPV DNA contamination cannot be ruled out as an explanation for high HPV prevalence in ESCC tissue studies with less stringent tissue procurement and processing protocols.

Relationship between HPV6b infection and esophageal cancer in Kazakh in Xinjiang Uygur Autonomous Region

AIM: To evaluate the association between HPV6b infection and esophageal cancer (EC) in Kazakh of Xinjiang, China.

METHODS: A case-control study was conducted with 120 cases of EC and 120 controls. The controls were matched by sex, nationality, area of residence and age difference within 5 years. HPV6b infection was identified by PsV neutralization assay from blood-serum. Chi-square was performed to identify risk factors.

RESULTS: The esophageal cancer infection rate was 27.5% in the cases while it was 22.5% in the controls. Infection rate of esophageal cancer in experiment group was not statistically different from the controls (χ² = 0.80, P = 0.371). HPV6b infection rate of the males was not statistically different from the females in both the cases and the controls (χ² = 0.31, 0.01, P = 0.58, 0.92). The infection rates of HPV6b in < 50, 50-59, 60-69 and ≥ 70 age groups, were 31.0%, 29.0%, 20.9% and 35.3%, respectively with no statistical differences detected among these groups in EC group (χ² = 1.67, P = 0.64). The infection rates of HPV6b were 19.4%, 13.5%, 30.6% and 31.3%, respectively in the controls with no statistical differences either (χ² = 3.93,P = 0.27).

CONCLUSION: The infection of HPV6b is common. The EC in Kazakh of Xinjiang has no association with HPV6b infection.

Squamous dysplasia and other precursor lesions related to esophageal squamous cell carcinoma

Squamous cell carcinoma is the most common tumor of the esophagus worldwide, and it is believed to develop through a sequence of dysplastic precursor lesions, which can be detected both endoscopically and microscopically. There are no published guidelines regarding treatment for dysplasia; however, most authorities recommend increased endoscopic surveillance, with biopsies, for patients with flat low-grade dysplasia and endoscopic mucosal resection, endoscopic submucosal dissection, or esophagectomy for patients with high-grade dysplasia. Future studies are needed to define appropriate endoscopic surveillance frequencies for patients with premalignant lesions of the esophagus. This article discusses squamous dysplasia in detail, which is the most important and well-described risk factor for squamous cell carcinoma of the esophagus.

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.

Human papillomavirus in esophageal squamous cell carcinoma in Colombia and Chile

AIM: To examine the presence of human papillomavirus (HPV) in esophageal squamous cell carcinoma (ESCC) specimens collected from Colombia and Chile located in the northern and southern ends of the continent, respectively.

METHODS: We examined 47 and 26 formalin-fixed and paraffin-embedded ESCC specimens from Colombia and Chile, respectively. HPV was detected using GP5+/GP6+ primer pair for PCR, and confirmed by Southern blot analysis. Sequencing analysis of L1 region fragment was used to identify HPV genotype. In addition, P16^INK4A protein immunostaining of all the specimens was conducted.

RESULTS: HPV was detected in 21 ESCC specimens (29%). Sequencing analysis of L1 region fragment identified HPV-16 genome in 6 Colombian cases (13%) and in 5 Chilean cases (19%). HPV-18 was detected in 10 cases (21%) in Colombia but not in any Chilean case. Since Chilean ESCC cases had a higher prevalence of HPV-16 (without statistical significance), but a significantly lower prevalence of HPV-18 than in Colombian cases (P = 0.011) even though the two countries have similar ESCC incidence rates, the frequency of HPV-related ESCC may not be strongly affected by risk factors affecting the incidence of ESCC. HPV-16 genome was more frequently detected in p16 positive carcinomas, although the difference was not statistically significant. HPV-18 detection rate did not show any association with p16 expression. Well-differentiated tumors tended to have either HPV-16 or HPV-18 but the association was not statistically significant. HPV genotypes other than HPV-16 or 18 were not detected in either country.

CONCLUSION: HPV-16 and HPV-18 genotypes can be found in ESCC specimens collected from two South American countries. Further studies on the relationship between HPV-16 presence and p16 expression in ESCC would aid understanding of the mechanism underlying the presence of HPV in ESCC.

No association between HPV infection and the neoplastic progression of esophageal squamous cell carcinoma: result from a cross-sectional study in a high-risk region of China

Esophageal cancer is a leading cause of cancer death, especially in developing countries. In high-risk regions, squamous cell carcinoma is the most common type of esophageal cancer, and its etiology remains poorly understood. The purpose of this study was to evaluate the association between human papillomavirus (HPV) infection and esophageal squamous cell carcinoma (ESCC) and related precursor lesions in a high-risk area of China. We conducted a cross-sectional study among adult inhabitants of Linxian, China. All subjects were interviewed about potential risk factors, had the length of their esophagus sampled by a balloon cytology examination and underwent endoscopy with mucosal iodine staining and biopsy of all unstained lesions. A multivalent HPV hybridization probe, Digene Hybrid Capture II (Gaithersburg, MD), which recognizes high-risk types 16, 18, 31, 33, 35, 39, 45, 51, 52, 56, 58, 59 and 68, was used to determine the HPV infection status of the cytologic specimens, and the endoscopic biopsies were used to classify each subject's esophageal disease. 740 subjects completed the cytologic and endoscopic exams, and 702 had adequate cytologic and biopsy specimens. Using a cutpoint of > or =3.0 pg/ml of HPV DNA to define a positive test, HPV positivity was identified in 13% (61/475) of subjects without squamous dysplasia, 8% (8/102) with mild dysplasia, 7% (6/83) with moderate dysplasia, 16% (6/38) with severe dysplasia and zero (0/4) with invasive ESCC. Changing the cutpoint defining a positive test did not change the association of HPV infection and dysplasia grade. In this high-risk population, infection of esophageal cells with high-risk HPV types occurs in 13% of asymptomatic adults with no evidence of squamous dysplasia and a similar proportion of individuals with mild, moderate or severe dysplasia. This suggests that HPV infection is not a major risk factor for ESCC in this high-risk Chinese population. Further studies are warranted to determine if infection with this agent is associated with neoplastic progression in a subset of cases.

Absence of human papillomavirus in esophageal carcinomas from southwestern Kenya

Esophageal squamous cell cancer is highly prevalent in south-western Kenya. The role of human papillomavirus (HPV) in esophageal cancers from this region was evaluated. Biopsies of 29 esophageal squamous cell cancers were assayed for HPV DNA sequences by reverse line blot polymerase chain reaction, using 27 HPV type-specific probes. Viral sequences were found in none of the specimens. These results suggest the HPV is unlikely to be an etiologic factor for esophageal squamous cell cancers in this region.

Human papillomavirus in squamous cell carcinoma of esophagus in a high-risk population

AIM: To investigate the relation of human papillomavirus (HPV) and esophageal squamous cell carcinoma (ESCC) in Iranian patients as compared to normal controls.

METHODS: Using MY09/MY11 consensus primers, we compared the prevalence of a HPV L1 gene in tumor tissues from 38 ESCC cases and biopsied tissues from 38 endoscopically normal Iranian individuals. We also compared the presence of HPV16 and HPV18 in the same samples using type-specific E6/E7 primers.

RESULTS: Fourteen (36.8%) of the 38 ESCC samples but only 5 (13.2%) of the 38 control samples were positive for the HPV L1 gene (P = 0.02). Five (13.2%) of the ESCC samples but none of the control samples were positive for the HPV16 E6/E7 gene (P = 0.05). Three (7.9%) of the ESCC samples and 5 (13.2%) of the control samples were positive for the HPV18 E6/E7 gene (P = 0.71).

CONCLUSION: Our data are consistent with HPV DNA studies conducted in other high-risk areas for ESCC. HPV should be considered as a potential factor contributing to the high incidence of ESCC in Iran and other high-incidence areas of the world.

Regulation of apoptosis by the papillomavirus E6 oncogene

Infection with human papillomaviruses is strongly associated with the development of multiple cancers including esophageal squamous cell carcinoma. The HPV E6 gene is essential for the oncogenic potential of HPV. The regulation of apoptosis by oncogene has been related to carcinogenesis closely; therefore, the modulation of E6 on cellular apoptosis has become a hot research topic recently. Inactivation of the pro-apoptotic tumor suppressor p53 by E6 is an important mechanism by which E6 promotes cell growth; it is expected that inactivation of p53 by E6 should lead to a reduction in cellular apoptosis, numerous studies showed that E6 could in fact sensitize cells to apoptosis. The molecular basis for apoptosis modulation by E6 is poorly understood. In this article, we will present an overview of observations and current understanding of molecular basis for E6-induced apoptosis.

Esophageal papillomatosis complicated by squamous cell carcinoma in situ

We present a case of esophageal papillomatosis with underlying squamous cell carcinoma in situ. An esophageal lesion resected from a 74-year-old woman demonstrated histological findings characteristic of squamous cell papilloma (fibrovascular core and numerous finger-like projections covered with hyperplastic squamous epithelium) and severe dysplasia characteristic of squamous cell carcinoma. The relation of squamous papilloma and squamous cell carcinoma is discussed. It is suggested that esophageal squamous cell papilloma is a premalignant lesion.

p53 polymorphism in human papillomavirus-associated Kazakh’s esophageal cancer in Xinjiang, China

AIM: To investigate the relationship between p53 codon 72 polymorphism and human papillomavirus (HPV) type 16 infection in Kazakh’s esophageal cancer (EC) in Xinjiang, China.

METHODS: Encoding regions of p53 codon 72 and HPV-16 E6 were amplified by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and polymerase chain reaction (PCR) methods using pairs of primary esophageal squamous cell carcinoma (SCC) tissue and corresponding normal mucosa, which were collected from 104 patients of Kazakh in Xinjiang, China.

RESULTS: Only arginine allele was detected in 70.1% (39/55) of HPV-16-E6- positive cases but only in 40.8% (20/49) of HPV-16-E6-negative cases (P < 0.05; OR, 3.53; 95%CI, 1.57-7.98). In contrast, such a significant correlation between p53 polymorphism and HPV infection was not evident in corresponding normal mucosae. The allele frequency of Arg allele in cancer cases (0.68) was higher than that in normal mucosa samples (0.54) (P < 0.05; OR, 1.80; 95%CI, 1.21-2.69).

CONCLUSION: p53 codon 72 Arg homozygous genotype is one of the high-risk genetic factors for HPV-associated SCC of Kazakh. Individuals carrying Arg allele compared to those with Pro allele have an increased risk for esophageal SCC.

Association between esophageal squamous cell carcinoma and human papillomavirus detected by Hybrid Capture II assay

From July 1999 to July 2000, 40 patients from the Surgical Oncology and Gastroenterology Departments of Irmandade da Santa Casa de Misericórdia de Porto Alegre were enrolled in a prospective study in order to find the frequency of human papillomavirus DNA (HPV-DNA) in esophageal squamous cell carcinoma. They were compared to 10 normal individuals (controls). Digene Inc. (Digene Corporation, Gaithersburg MD, USA) Hybrid Capture II assay, a chemoluminescent method, was used in both groups. The samples were collected from the tumor group by endoscopic biopsy in 20 cases, and by surgical specimens in the other 20 cases; the control group all underwent endoscopic biopsies. The cut-off point in the analytical assay for HPV-DNA was 1.0 pg/mL. Digene Corp. Hybrid Capture II assay tests HPV-DNA and differentiates high and low-risk for malignization virus groups. Gender, age, location of the tumor in esophagus and degree of differentiation on histology were also analyzed. There was one positive case (1.14 pg/mL), a 2.5% frequency of low-risk HPV-DNA type in the esophageal squamous cell carcinoma group (CI 95%: 0.00-7.34%). This group of patients consisted of 30 male and 10 female individuals, similar to the distribution seen in large series of such patients from the Brazilian population. The mean age was 63 years. Endoscopic samples of 10 patients who underwent endoscopic biopsy procedure for aleatory reasons, with normal looking esophageal mucosa, were tested to detect HPV-DNA, as controls. There was one positive case (1.17 pg/mL) of high-risk HPV-DNA type, resulting in a 10% positive rate. HPV-DNA is rarely found in esophageal squamous cell carcinomas: we found a 2.5% frequency, with confidence interval of 0-7.34%; and this is in the same range of controls (10% frequency, with CI: 9.1-10.9%). Both patients had a viral load quite near the 1.0 pg/mL cut-off point.

Detection of human papillomavirus in Chinese esophageal squamous cell carcinoma and its adjacent normal epithelium

AIM: To investigate the putative role of human papillomavirus (HPV) infection in the carcinogenesis of esophageal squamous cell carcinoma in China.

METHODS: Twenty-three esophageal squamous cell carcinoma samples and the distal normal epithelium from Shanxi Province, and 25 more esophageal squamous cell carcinoma samples from Anyang city, two areas with a high incidence of esophageal cancer in China, were detected for the existence of HPV-16 DNA by PCR, mRNA in situ hybridization (ISH) and immunohistochemistry (IHC) targeting HPV-16 E6 gene.

RESULTS: There were approximately 64% (31/48) patients having HPV-16 DNA in tumor samples, among them nearly two-thirds (19/31) samples were detected with mRNA expression of HPV-16 E6. However, in the normal esophageal epithelium from cancer patients, the DNA and mRNA of HPV-16 were found with much less rate: 34.7% (8/23) and 26.1% (6/23) respectively. In addition, at protein level detected by IHC assay, 27.1% (13/48) tumor samples had virus oncoprotein E6 expression, while only one case of normal epithelium was found positive.

CONCLUSION: HPV infection, especially type 16, should be considered as a risk factor for esophageal malignancies in China.

Viral load of HPV in esophageal squamous cell carcinoma

We previously reported the presence of HPV DNA in esophageal squamous cell carcinoma (ESCC) cases from Hong Kong and Sichuan. The role of HPV in the carcinogenesis of ESCC remains unclear, partly due to the large variations in infection rates reported by different studies. While some of these variations may truly reflect different HPV infection rates in ESCC among different geographic regions, differences in sensitivity and specificity of the detection methods used also contribute. In the present study, we used quantitative real-time PCR to determine the copy numbers of HPV-16 and HPV-18 in ESCC from 5 different regions of China with different incidence rates of ESCC. Conforming to our previous reports, HPV infection was detected in 2-22.2% of samples. Infection with HPV-16 was again shown to be more common than that with HPV-18 among Chinese ESCC patients. The copy number of HPV-16 in these ESCC cases ranged from < or =1 to 157 copies/genome equivalent, with 65% of samples harboring fewer than 10 copies/genome equivalent. The median copy number of HPV-18 was 4.9/genome equivalent. Assays were validated using cervical carcinoma cell lines with known copy numbers of HPV-16 or HPV-18. The relatively low HPV copy number and infection rate in ESCC suggest that HPV is unlikely to play as essential a role in the carcinogenesis of ESCC as in cervical cancer. However, with the consistent detection of oncogenic HPVs in ESCC from some regions of China, the possibility of HPV infection being one of the multiple risk factors of ESCC in some geographic areas cannot be excluded.

Detection of human papillomavirus DNA and p53 gene mutations in esophageal cancer samples and adjacent normal mucosa

BACKGROUND/AIM

There is evidence of a possible etiological role of human papillomaviruses (HPVs) in the development of esophageal tumors. Loss of function of the wild-type p53 tumor suppressor gene product by binding to E6 oncoproteins of high-risk HPVs is considered an important event in tumor development. The aim of this study was to verify the prevalence of HPV infection and p53 mutation in esophageal tumor tissue samples and in the adjacent normal mucosa in patients from a high-risk area in Italy.

METHODS

DNA from 33 biopsy specimens (17 tumor sample biopsies and 16 samples of adjacent normal mucosa) was screened for HPV DNA using two polymerase chain reaction based procedures. Restriction fragment length polymorphism analysis was used for typing. Screening of p53 mutations was performed with polymerase chain reaction-single strand conformation polymorphism analysis and DNA sequencing.

RESULTS

Overall, 8 of 17 patients presented HPV DNA; HPV 16 was detected in 4 of 8 samples. Samples from tumors and adjacent mucosa were positive for mucosal HPVs in 7 of 17 and 4 of 16 cases, respectively. In 1 case, HPV DNA was detected in the normal mucosa only. None of the samples contained HPVs of the epidermodysplasia verruciformis or cutaneous groups. Mutations of p53 were detected in two HPV DNA negative samples. In both cases, the mutation was present in the tumor only.

CONCLUSIONS

Our results are in favor of the involvement of both aberrant p53 expression and HPV infection in the development of esophageal tumors. The high HPV infection rate in patients from a high-risk region suggests that subjects harboring HPVs (in particular HPV 16) in the esophagus should be considered at risk of esophageal malignancies.

Detection of human papillomavirus in esophageal carcinoma

The aim of the study was to assess the prevalence of human papillomavirus (HPV) in the esophagus in the coastal region of Eastern Guangdong, Southern China, an area with a high incidence of esophageal carcinoma. Fresh surgical resection esophageal specimens were obtained from 176 esophageal carcinoma patients admitted to the Tumor Hospital of Shantou University Medical College. The samples were subjected to polymerase chain reaction (PCR) to detect HPV infection using consensus and type-specific primers for HPV type 6, 11, 16, and 18. The incidence rate was 65.5%, 69.1%, and 60% in tissues of cancerous, paracancerous and normal mucosa, respectively. Further analysis of the distribution of HPV types in the three sections of tissues showed that the high-risk HPV types 16 and 18 were found mainly in the cancer cells (43.2%), whereas the low-risk HPV types 6 and 11 were seen mainly in the normal mucosa (52.3%). The total infection rate of the high-risk HPV types 16 and HPV 18 was the highest in cancerous tissues (54.5%), followed by paracancerous tissues (19.5%), and the lowest in normal mucosa (11.7%). There was high incidence of HPV infection in the esophageal epithelium in Eastern Guangdong, Southern China, where esophageal carcinoma is prevalent. HPV was seen in the normal, paracancerous and cancerous tissues, with the high-risk HPV type 16 and 18 more common in cancerous tissues. The results indicate that the high incidence of esophageal carcinoma in this area is associated with HPV infection.

HPV infections and oesophageal cancer

The first reports suggesting an involvement of human papillomavirus (HPV) in the development of both benign and malignant squamous cell tumours of the oesophagus date back to 1982. Since then, a substantial amount of literature has accumulated on this subject, summarised in this review. To date, 239 oesophageal squamous cell papillomas have been analysed in 29 separate studies using different HPV detection methods, with HPV being detected in 51 (21.3%) cases. Many more squamous cell carcinomas have been analysed: of the 1485 squamous cell carcinomas analysed by in situ hybridisation, 22.9% were positive for HPV DNA, as were 15.2% of the 2020 cases tested by the polymerase chain reaction. In addition, evidence derived from large scale serological studies, animal experiments, and in vitro studies is discussed in the light of the highly variable geographical incidence rates of oesophageal carcinoma worldwide. It may be that the (multifactorial) aetiology of oesophageal cancer differs greatly between those geographical areas with a low risk and those with a high risk for this disease. Oncogenic HPV types seem to play an important causal role, particularly in high risk areas.

HPV infections and oesophageal cancer

The first reports suggesting an involvement of human papillomavirus (HPV) in the development of both benign and malignant squamous cell tumours of the oesophagus date back to 1982. Since then, a substantial amount of literature has accumulated on this subject, summarised in this review. To date, 239 oesophageal squamous cell papillomas have been analysed in 29 separate studies using different HPV detection methods, with HPV being detected in 51 (21.3%) cases. Many more squamous cell carcinomas have been analysed: of the 1485 squamous cell carcinomas analysed by in situ hybridisation, 22.9% were positive for HPV DNA, as were 15.2% of the 2020 cases tested by the polymerase chain reaction. In addition, evidence derived from large scale serological studies, animal experiments, and in vitro studies is discussed in the light of the highly variable geographical incidence rates of oesophageal carcinoma worldwide. It may be that the (multifactorial) aetiology of oesophageal cancer differs greatly between those geographical areas with a low risk and those with a high risk for this disease. Oncogenic HPV types seem to play an important causal role, particularly in high risk areas.

Human papillomavirus 16 E6 is associated with the nuclear matrix of esophageal carcinoma cells

AIM: To explore the etiologic role of HPV infection in esophageal carcinoma, and the association of HPV-16 E6 with the nuclear matrix of carcinoma cells.

METHODS: Two esophageal carcinoma cell lines, EC/CUHK1 and EC/CUHK2, were tested for HPV-16 E6 subgenetic fragment by polymer a se chain reaction amplification of virus DNA associated nuclear matrix. RT-PCR and immunocytochemistry were also used to visualize the expression of E6 subgene in the cells.

RESULTS: The HPV-16 E6 subgenetic fragment was found to be present in nuclear matrix-associated DNA, E6 oncoprotein localized in the nucleus where it is tightly associated with nuclear matrix after sequential extraction in EC/CUHK2 cells. It was not detected, however, in EC/CUHK1 cells.

CONCLUSION: The interaction between HPV-16 E6 and nuclear matrix may contribute to the virus induced carcinogenesis in esophageal carcinoma.

Squamous cell cancer of the oesophagus

Squamous cell cancer is the most common neoplasm of the oesophagus worldwide, with an enormous variation in its global incidence. Several risk factors, such as achalasia, Plummer-Vinson syndrome, coeliac disease and nutritional factors, have been identified. The surveillance of patients, especially those with tylosis or caustic ingestion, has been recommended. Vital staining with iodine may improve the diagnosis of early cancer. The endoscopic management of early cancer and dysplasia by minimal invasive techniques such as photodynamic therapy or mucosal resection has become attractive for many of these patients with co-morbidity.