Detection of HPV DNA in esophageal cancer specimens from different regions and ethnic groups: a descriptive study

Prevalence and risk factors of oral human papillomavirus infection among 4212 healthy adults in Hebei, China

BACKGROUND

Human papillomavirus (HPV) infection is an essential cause of oropharyngeal squamous cell carcinoma that is increasing in incidence worldwide. However, little is known about the epidemiology of oral HPV infection among healthy adults in China.

METHODS

A study in northern China was conducted in 2021 as baseline data of Diverse Life-Course Cohort (DLCC). Residents who aged above 20 were eligible to participate. Oral swab specimens and questionnaires were collected from 4226 participants. HPV DNA in oral exfoliated cells was tested by Nested Polymerase Chain Reaction approach and sequencing. Univariate and multivariate analyses were performed to assess the associations between exposure factors and oral HPV infection.

RESULTS

Overall prevalence of oral HPV infection was 4.08% (95%CI, 3.69%-4.68%). The most prevalent HPV type detected was HPV-81 (1.35%; 95% CI, 1.00%-1.70%), followed by HPV-16 (0.64%; 95% CI, 0.40%-0.88%). Oral HPV infection presented a bimodal pattern with respect to age in male and female participants. Oral HPV prevalence of male participants was significantly higher than prevalence of female participants (5.0% versus 3.6%, P = 0.041). Prevalence of oral HPV was higher among current smokers (OR = 1.59; 95% CI, 1.11-2.29; P = 0.039) and current drinkers (OR = 1.60; 95% CI, 1.14-2.25; P = 0.023). Current alcohol consumption was independently associated with oral HPV infection (OR = 1.74; 95% CI, 1.22-2.50; P = 0.010).

CONCLUSIONS

Among healthy adults aged above 20 in Hebei, China, the prevalence of high-risk HPV infection was 1.92% (95%CI, 1.51%-2.34%). Oral HPV prevalence was independently associated with alcohol consumption. More tailored prevention strategies are needed to prevent oral HPV infection through smoking cessation, reduction of alcohol consumption, and HPV vaccination.

Epidemiology of Oral Human Papillomavirus Infection among Diverse Chinese Adults in Typical Areas of China: Findings from the DLCC Study

BACKGROUND

Human papillomavirus (HPV) infection is a predominant cause of oropharyngeal squamous cell carcinoma. However, there is limited knowledge about the epidemiology of oral HPV infections among adults in China.

METHODS

We collected data from a prospective cohort that enrolled participants in Mainland China. A total of 9,867 participants ages at least 20 years provided oral swab specimens in typical areas of China (Hebei and Guangdong provinces) in 2021. HPV DNA in oral exfoliated cells was tested using nested PCR and sequencing. Prevalence among subpopulations was compared. Multivariable logistic regression models were employed to assess possible factors influencing oral HPV infection.

RESULTS

The overall prevalence of oral HPV infection was 3.0% [95% confidence interval (CI): 2.68-3.36]. Among those infected, 1.3% (1.08-1.53) were infected with high-risk HPV types. Men had a higher age-standardized HPV infection prevalence (3.6%, 2.96-4.29) compared with their female counterparts (2.7%, 2.35-3.12). People in Hebei had a higher age- and sex-standardized prevalence (4.1%, 3.50-4.70) than those in Guangdong (2.2%, 1.80-2.56). Generally, men (OR and 95% CI: 1.42, 1.09-1.85) and people in Hebei (2.01, 1.53-2.65) had higher odds of any type of HPV infection. In addition, people living in urban areas had a 2.15-fold (1.43-3.26) higher odds of high-risk HPV infection.

CONCLUSIONS

This study reveals a low prevalence of oral HPV infection with significant geographic and sex differences among Chinese population.

IMPACT

This is the first study to report the epidemiologic characteristics of oral HPV infection among Chinese adults in diverse geographic areas with large sample size.

Exploiting the Molecular Basis of Oesophageal Cancer for Targeted Therapies and Biomarkers for Drug Response: Guiding Clinical Decision-Making

Worldwide, oesophageal cancer is the sixth leading cause of deaths related to cancer and represents a major health concern. Sub-Saharan Africa is one of the regions of the world with the highest incidence and mortality rates for oesophageal cancer and most of the cases of oesophageal cancer in this region are oesophageal squamous cell carcinoma (OSCC). The development and progression of OSCC is characterized by genomic changes which can be utilized as diagnostic or prognostic markers. These include changes in the expression of various genes involved in signaling pathways that regulate pathways that regulate processes that are related to the hallmarks of cancer, changes in the tumor mutational burden, changes in alternate splicing and changes in the expression of non-coding RNAs such as miRNA. These genomic changes give rise to characteristic profiles of altered proteins, transcriptomes, spliceosomes and genomes which can be used in clinical applications to monitor specific disease related parameters. Some of these profiles are characteristic of more aggressive forms of cancer or are indicative of treatment resistance or tumors that will be difficult to treat or require more specialized specific treatments. In Sub-Saharan region of Africa there is a high incidence of viral infections such as HPV and HIV, which are both risk factors for OSCC. The genomic changes that occur due to these infections can serve as diagnostic markers for OSCC related to viral infection. Clinically this is an important distinction as it influences treatment as well as disease progression and treatment monitoring practices. This underlines the importance of the characterization of the molecular landscape of OSCC in order to provide the best treatment, care, diagnosis and screening options for the management of OSCC.

The Roles of the Virome in Cancer

Viral infections as well as changes in the composition of the intestinal microbiota and virome have been linked to cancer. Moreover, the success of cancer immunotherapy with checkpoint inhibitors has been correlated with the intestinal microbial composition of patients. The transfer of feces-which contain mainly bacteria and their viruses (phages)-from immunotherapy responders to non-responders, known as fecal microbiota transplantation (FMT), has been shown to be able to convert some non-responders to responders. Since phages may also increase the response to immunotherapy, for example by inducing T cells cross-reacting with cancer antigens, modulating phage populations may provide a new avenue to improve immunotherapy responsiveness. In this review, we summarize the current knowledge on the human virome and its links to cancer, and discuss the potential utility of bacteriophages in increasing the responder rate for cancer immunotherapy.

Cancer Etiology and Prevention Principle: "1 + X"

Cancer was previously thought to be an inevitable aspect of human health with no effective treatments. However, the results of in-depth cancer research suggest that most types of cancer may be preventable. Therefore, a comprehensive understanding of the disparities in cancer burden caused by different risk factors is essential to inform and improve cancer prevention and control. Here, we propose the cancer etiology and prevention principle "1 + X," where 1 denotes the primary risk factor for a cancer and X represents the secondary contributing risk factors for the cancer. We elaborate upon the "1 + X" principle with respect to risk factors for several different cancer types. The "1 + X" principle can be used for precise prevention of cancer by eliminating the main cause of a cancer and minimizing the contributing factors at the same time.

Human papilloma virus: A review study of epidemiology, carcinogenesis, diagnostic methods, and treatment of all HPV-related cancers

Background: Human papillomavirus (HPV) infection is considered as the most common viral sexually transmitted infection worldwide. This poses an increasingly interdisciplinary medical challenge. Since there is vast scattered information in databases about HPV and the correlated diseases, we decided to collect useful data so that the experts can get a more comprehensive view of HPV. Methods: In this article, HPV-associated diseases, prevalence, prevention, and new treatments are discussed. The retrieved articles reporting the latest data about the required information for our review were selected through searching in Web of Science, Scopus, Medline (PubMed), EMBASE, Cochrane Library, Ovid, and CINHAL with language limitations of English and German. Results: There are 2 groups of HPVs: (1) low-risk HPV types that can lead to genital warts, and (2) high-risk HPV types that are involved in HPV-associated oncogenesis. About 70% of all sexually active women are infected and most of these infections heal within many weeks or months. In the case of HPV-persistence, a risk of preneoplasia or carcinoma exists. These types of viruses are responsible for the existence of genitoanal, gastrointestinal, urinary tract, and head and neck tumors. There is still no definite successful treatment. The detection of HPV-related condylomata occurs macroscopically in women and men, and the diagnosis of the precursors of cervical carcinoma in women is possible by Pap smear. Conclusion: For extragenital manifestations, there is no structured early detection program. Meanwhile, studies on HPV vaccines confirm that they should be used for the primary prevention of HPV-dependent diseases. However, we need more research to find out the real advantages and disadvantages of vaccines.

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.

Prevalence and genotype distribution of human papillomavirus among women with cervical lesions in Shenzhen city, China

There is currently a lack of sufficient data on human papillomavirus (HPV)-attributable cervical carcinoma in China. Accordingly, we aimed to determine the prevalence and genotype distribution of HPV among women with cervical lesions in Shenzhen, in order to evaluate the potential benefit of HPV vaccination programs and inform cervical cancer control policies. We enrolled 5,255 patients who were admitted to the University of Chinese Academy of Sciences Shenzhen Hospital from January 2017 to December 2019. The HPV prevalence and genotype distribution were analyzed using the 21 HPV GenoArray diagnostic assay. A total of 937/5,255 patients showed HPV-positivity (prevalence rate 17.83%), of whom 85.81% (804/937) had high-risk HPV infection. HPV52 was the most prevalent genotype (4.72%, 248/5,255), followed by HPV58 (3.04%, 160/5,255), and HPV16 (2.72%, 143/5,255). The HPV prevalence rates among women with a normal cervix, low-grade intraepithelial lesions, high-grade intraepithelial lesions, invasive cervical cancer, and other characteristics were 15.63% (50/320), 58.65% (61/104), 80.00% (44/55), 88.57% (31/35), and 15.84% (751/4,741), respectively. HPV16, HPV18, and HPV52 accounted for the majority of cervical lesions, and the infection rates of HPV16 and HPV18 gradually increased with intraepithelial lesion progression (both P < .001). Our study found that HPV16, HPV52, and HPV18 played important roles in the occurrence and development of cervical lesions. This finding has the potential to guide the formulation of HPV screening and vaccination programs and preventive strategies for HPV-attributable cancer in this region.

Analysis of human papillomavirus 16 E6/E7 and L1 in the bronchial brushing cells of patients with squamous cell carcinoma of the lungs

A type of high-risk human papillomavirus (HPV), HPV16 takes part in lung carcinogenesis. E6 and E7 are the major oncoproteins of high-risk HPV, and L1 is the major capsid protein. In this study, we detected their mRNA expressions and analyzed their relationship in the bronchial brushing cells of 211 patients with malignant lesions (squamous cell carcinoma of the lungs) and benign lesions (pneumonia and tuberculosis) by quantitative real-time PCR. HPV16 E6, E7, and L1 mRNA expressions in the malignant group were statistically higher than in benign group (P<0.05), and their mRNA expressions in the squamous cell carcinoma of the lung group were statistically higher than in pneumonia group (P<0.05). There was a negative correlation between L1 and E6 expression in the squamous cell carcinoma of the lungs group (Spearman correlation coefficient r=-0.498, P=0.000). An ROC curve shows that the combination of L1 and E6 is a significant predictor for the diagnosis of squamous cell carcinoma of the lungs (AUC: 0.878; Sensitivity: 96.00%; Specificity: 77.91%), which could make up for the deficiency of cytologic testing. The combined detection of HPV16 E6 and L1 mRNA expressions in bronchial brushing cells by quantitative real-time PCR has a great significance for the diagnosis of squamous cell carcinoma of the lungs, providing new therapeutic targets for the clinical treatment of squamous cell carcinoma of the lungs.

Effects of HPV16E6 transfection on the biological behavior of Eca109 and Eca9706 cells

The aim of the present study was to investigate the effect of HPV16E6 gene integration on the biological behavior of Eca109 and Eca9706 cells. This was evaluated through positive liposome transfection of HPV16E6 into Eca109 cells and Eca9706 cells. The transfection efficiency was evaluated by calculating the ratio of fluorescent cells to total cells. After stable screening, reverse transcription-polymerase chain reaction (RT-PCR) was performed to detect the target gene and HPV16E6mRNA inside the cells. The distribution of HPV16E6 in esophageal carcinoma cells was observed by immunofluorescence and western blot analysis. A CCK-8 assay was performed to detect cell proliferation. The migration rate was measured by a wound healing assay, and a Transwell Matrigel invasion assay was used to detect invasive ability. The results of RT-PCR, immunofluorescence and western blot analyses indicated that HPV16E6 gene was expressed in the target group. The proliferation rates and clone group numbers were significantly higher in HPV16E6-transfected cell groups compared with nonsense-transfected (negative control) cell groups. The wound healing and Transwell invasion assays indicated that the migration rate and invasive ability were also significantly higher in the HPV16E6-transfected cell groups compared with negative control groups. In conclusion, Eca109 and Eca9706 cell lines with integration of HPV16E6 were successfully established in the present study. It was demonstrated that HPV16E6 expression enhanced the proliferation and migration of esophageal cancer cells. HPV16E6 may serve a key function in the occurrence and development of esophageal cancer.

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.

The prevalence of viral agents in esophageal adenocarcinoma and Barrett's esophagus: a systematic review

BACKGROUND AND AIMS

Human papilloma virus (HPV), which may reach the esophagus through orogenital transmission, has been postulated to be associated with esophageal adenocarcinoma (EAC). A systematic review of the literature investigating the prevalence of infectious agents in EAC and Barrett's esophagus (BE) was carried out.

METHODS

Using terms for viruses and EAC, the Medline, Embase, and Web of Science databases were systematically searched for studies published, in any language, until June 2016 that assessed the prevalence of viral agents in EAC or BE. Random-effects meta-analyses of proportions were carried out to calculate the pooled prevalence and 95% confidence intervals (CIs) of infections in EAC and BE.

RESULTS

A total of 30 studies were included. The pooled prevalence of HPV in EAC tumor samples was 13% (n=19 studies, 95% CI: 2-29%) and 26% (n=6 studies, 95% CI: 3-59%) in BE samples. HPV prevalence was higher in EAC tissue than in esophageal tissue from healthy controls (n=5 studies, pooled odds ratio=3.31, 95% CI: 1.15-9.50). The prevalence of Epstein-Barr virus (EBV) in EAC was 6% (n=5, 95% CI: 0-27%). Few studies have assessed other infectious agents. For each of the analyses, considerable between-study variation was observed (I=84-96%); however, sensitivity analyses did not show any major sources of heterogeneity.

CONCLUSION

The prevalence of HPV and EBV in EAC is low compared with other viral-associated cancers, but may have been hampered by small sample sizes and detection methods susceptible to fixation processes. Additional research with adequate sample sizes and high-quality detection methods is required.

Tumor suppressor microRNA-34a inhibits cell migration and invasion by targeting MMP-2/MMP-9/FNDC3B in esophageal squamous cell carcinoma

MicroRNAs (miRNAs) are a large family of small, non-coding RNAs that play a pivotal role in tumorigenesis. miR‑34a, which is a member of the miR-34 family, is a downstream target of p53. Increasing evidence shows that miR-34a dysregulation may contribute to tumor development and progression in numerous cancers, including esophageal squamous cell carcinoma (ESCC). However, the mechanism of miR-34a in the regulation of ESCC cells need to be further elucidated because of the complex regulative network of miRNAs. The miR-34a expression in ESCC samples has been confirmed using quantitative reverse transcription polymerase chain reaction. The effects of miR-34a on cell migration and invasion were examined in ESCC cell lines using wound healing and Transwell assays, respectively. The effects of miR-34a on matrix metalloproteinase (MMP)-2 and -9 and fibronectin type III domain containing 3B (FNDC3B) expression levels were detected by luciferase reporter assays and western blot analysis. Quantitative polymerase chain reaction revealed that the miR‑34a expression is significantly downregulated in the ESCC tissues compared to that in the adjacent normal tissues. miR-34a overexpression was significantly suppressed migration and invasion in the ESCC cells and simultaneously inhibited the MMP-2, MMP-9 and FNDC3B expression levels by targeting the coding and 3'-untranslated regions, respectively. The findings indicated that microRNA‑34a suppresses cell migration and invasion by targeting MMP-2, MMP-9, and FNDC3B in ESCC.

E6-Specific Detection and Typing of Human Papillomaviruses in Oral Cavity Specimens from Iranian Patients

Background:

Detection and quantification of human Papillomavirus (HPV) genome in oral carcinoma play an important role in diagnosis, as well as implications for progression of disease.

Methods:

We evaluated tissues from 50 esopharyngeal cancers collected from different regions of Iran for HPV E6 using the two type-specific primers sets. E6 gene of HPV genotypes was amplified by specific primers. The sensitivity of PCR assay was analyzed and determined using HPV-DNA-containing plasmids. Real-time PCR was utilized to determine the prevalence and HPV viral load in patients with oral cavity squamous cell carcinoma.

Results:

Eighteen (36%) specimens were positive for HPV. Among the 18 positive specimens, 10 showed HPV-18 (55.55%), and 8 specimens were positive for HPV-11 (44.44%). Of the 18 infected specimens, 6 (33.32%) and 12 (66.65%) were identified as high-titer and low-titer viral load, respectively.

Conclusions:

The PCR-based assay, developed in the current study, could be used for HPV detection, quantification, and genotyping in epidemiological and clinical studies.

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.

p53 expression but not p16(INK4A) correlates with human papillomavirus-associated esophageal squamous cell carcinoma in Kazakh population

Background

p16^INK4A expression has been used as a surrogate marker for human papillomavirus (HPV) infection in cervical cancer and head and neck cancer. p53 has also been reported as a feasible marker to identify HPV-positive oropharyngeal carcinoma and penile lesions. This study aimed to investigate p16^INK4A and p53 expression levels and their correlation with HPV status and clinical parameters in Kazakh patients with esophageal squamous cell carcinoma.

Methods

Immunohistochemical expression of p16^INK4A and p53 were evaluated in 163 cases of esophageal squamous cell carcinoma in Kazakh patients. The presence of HPV DNA was detected by polymerase chain reaction.

Results

p16^INK4A-positive expression was detected in 19.0 % of patients, and its expression was significantly correlated with a lower frequency of lymph node metastasis (p = 0.038). By contrast no significant association was found between p16^INK4A-positive expression and HPV status (correlation coefficient = -0.062, p = 0.499). p16^INK4A-positive expression did not affect the odds of tumors being HPV positive (odds ratio [OR] = 0.727 with 95 % confidence interval [CI] = 0.288–1.836). The sensitivity of p16^INK4A-positive expression as an HPV marker was 0.164, with a specificity of 0.788 and a positive predictive value of 0.391. p53-positive expression was present in 88.3 % of all cases. Although no significant correlation with available clinical parameters was found, a significantly inverse correlation was observed between p53 expression and HPV status (correlation coefficient = -0.186, p = 0.039). Moreover, p53-positive expression decreased the odds of tumors being HPV positive (OR = 0.292 with 95 % CI = 0.086–0.990). The sensitivity of p53-negative expression as an HPV marker was 0.179, with a specificity of 0.940 and a positive predictive value of 0.714. The overall HPV prevalence was high (45.5 %) in Kazakh patients, with no significant association between HPV positivity and available clinical parameters or combined p16^INK4A/p53 expression.

Conclusions

p16^INK4A-positive expression was associated with lymph node metastasis. Results indicate that p53-negative expression and not p16^INK4A-positive expression may be used as a marker for HPV status in ESCC; however, this finding requires further studies for validation.

Prevalence and Associated Risk Factors of Human Papillomavirus in Healthy Skin Specimens Collected from Rural Anyang, China, 2006-2008

Skin infections with cutaneous human papillomavirus (HPV) have been linked to the development of non-melanoma skin cancer, in which mucosal HPV may also play a crucial role. However, systematic investigations of the distribution and associated factors of HPV infection in healthy skin of the general population are scarce. HPV DNA from palmar exfoliated cells of 2,087 individuals was detected by FAP6085/64 and SPF1/GP6+ primers followed by sequencing. A total of 338 papillomavirus types were detected, with HPV-3, HPV-57, and HPV-49 being the most dominant types. The overall prevalence for HPV DNA on skin was 79.92% and for alpha-, beta-, and gamma-HPV were 27.07%, 38.76%, and 29.56%, respectively. Having multiple lifetime sexual partners (adjusted odds ratio 1.60), being a migrant worker (adjusted odds ratio 2.05, reference: farmers), and frequent bathing (Ptrend = 0.001) were associated with alpha-HPV DNA presence. Advancing age increased the detection risk of beta-HPV (Ptrend = 0.001). Higher education (Ptrend = 0.017) and frequent bathing (Ptrend = 0.001) were positively related to gamma-HPV positivity. This study demonstrates that alpha-HPV commonly exists on healthy skin of the general population in rural China, and alpha- and gamma-HPV infections are related to certain behaviors, different from beta-HPV infection. These findings are crucial to better understanding the biology of HPV infection and may be suggestive of the potential transmission of these viruses.

C3-Luc Cells Are an Excellent Model for Evaluation of Cellular Immunity following HPV16L1 Vaccination

C3 and TC-1 are the two model cell lines most commonly used in studies of vaccines and drugs against human papillomavirus (HPV) infection. Because C3 cells contain both the HPV16 E and L genes, but TC-1 cells contain only the HPV16 E genes, C3 cells are usually used as the model cell line in studies targeting the HPV16 L protein. However, expression of the L1 protein is difficult to detect in C3 cells using common methods. In our study, Short tandem repeat analysis (STR) was used to demonstrate that C3 cells are indeed derived from mice, PCR results show that HPV16 L1, E6 and E7 genes were detected in C3 genomic DNA, and RT-PCR results demonstrated that L1 transcription had occurred in C3 cells. However, the expression of C3 protein was not found in the results of western blot and immunohistochemistry (IHC). Growth and proliferation of C3 were inhibited by mice spleen lymphocytes that had been immunized with a vaccine against HPV16L1. The luciferase gene was integrated into C3 cells, and it was confirmed that addition of the exogenous gene had no effect on C3 cells by comparing cell growth and tumor formation with untransformed cells. Cells stably expressing luciferase (C3-luc) were screened and subcutaneously injected into the mice. Tumors became established and were observed using a Spectrum Pre-clinical in Vivo Imaging System. Tumor size of mice in the different groups at various time points was calculated by counting photons. The sensitivity of the animals to the vaccine was quantified by statistical comparison. Ten or 30 days following injection of the C3-luc cells, tumor size differed significantly between the PBS and vaccine groups, indicating that C3 cells were susceptible to vaccination even after tumors were formed in vivo.

Prevalence of HPV infection among 28,457 Chinese women in Yunnan Province, southwest China

Human papillomavirus (HPV) infection plays a key role in the development of cervical cancer. The aim of the current study was to investigate the HPV type distribution in Chinese women from Yunnan Province, southwest China. A total of 28,457 individuals ranging in age from 17-84 years were recruited from 13 clinical hospitals located in 10 different regions of Yunnan Province. Cervicovaginal swabs were collected from each participant, and HPV screening was performed using Luminex xMAP technology. Our results showed that the HPV prevalence was 12.9% in Yunnan Province. Overall, 10.6% of the individuals were positive for a single HPV type, and 2.3% were positive for multiple types. Among the individuals who tested positive for a single HPV type and multiple HPV types, the three most prevalent high-risk types were 52, 16, and 58. Age subgroup analysis showed two peaks for the frequencies of single and multiple HPV infections, one for the group of women under 25 years old, and the other for the group over 56 years old. Here, we present data regarding the prevalence and type distribution of HPV infection, which will aid in the estimation of the potential clinical benefit and cost-effectiveness of HPV screening and vaccination in China.

Type-specific detection of human papillomaviruses in Kazakh esophageal squamous cell carcinoma by genotyping both E6 and L1 genes with MALDI-TOF mass spectrometry

BACKGROUND

Many studies have suggested a relationship between human papillomavirus (HPV) infection and the risk of esophageal squamous cell carcinoma (ESCC). However, findings are inconclusive, potentially because of geographic heterogeneity and variations in detection methods.

OBJECTIVES

We sought to further investigate the prevalence of HPV with a new detection method, the MassARRAY Sequenom technique, in esophageal squamous cell carcinomas occurring in patients belonging to Kazakh populations in Xinjiang, China.

STUDY DESIGN

In the present study, a novel genotyping method for detecting 30 HPV genotypes, specifically by genotyping both the HPV E6 and L1 genes with multiplex PCR using matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) (PCR-MS) was first adopted to evaluate HPV genotypes in 89 esophageal cancer samples and 49 matched adjacent normal esophageal tissues.

RESULTS

Six HPV genotypes (HPV6, HPV16, HPV33, HPV39, HPV51, and HPV82) were present in at least 51.7% of the esophageal carcinoma tissues, which was significantly greater than 28.6% prevalence among controls (P < 0.05). HPV16 was the most common of all the genotypes investigated (HPV16 prevalence in carcinoma tissue: 49.4%; odds ratio 3.02, 95% confidence interval 1.39-6.53). HPV-positive ESCC patients were generally younger than HPV-negative patients (P = 0.04). In addition, HPV infection was more common in cases of well-differentiated and shallower invasive depth.

CONCLUSIONS

Based on this new detection method, our findings reiterate the possibility that HPV infection (especially HPV16) may be involved in the etiology of esophageal carcinoma in the Kazakh populations and that HPV E6 gene positivity may be associated with prognosis of patients.

Prevalence of human papillomavirus 16 in esophageal cancer among the Chinese population: a systematic review and meta-analysis

BACKGROUND AND AIM

No firm evidence of HPV infection in esophageal cancer has been established to date. The aim of this meta-analysis was to investigate the prevalence of HPV 16 in esophageal cancer in China, which had a high burden of the disease.

MATERIALS AND METHODS

Studies on HPV infection and esophageal cancer were identified and a random-effects model was used to pool the summary prevalence and corresponding 95% confidence intervals (CIs).

RESULTS

A total of 3,429 esophageal cancer cases were evaluated from 26 eligible studies in this meta-analysis. The summary estimate for HPV16 prevalence was 0.381 (95% CI: 0.283, 0.479). The prevalence varied by geographical areas of the study, publication year, HPV detection method and types of specimen. In sensitivity analysis, HPV 16 prevalence ranged from 0.368 (95% CI: 0.276, 0.460) to 0.397 (95% CI: 0.286, 0.508).

CONCLUSIONS

The results indicate a relatively high level of HPV 16 prevalence in esophageal cancer among Chinese population, although there was variation between different variables. Further studies are needed to elucidate the role of HPV in esophageal carcinogenesis with careful consideration of study design and laboratory detection method, providing more accurate assessment of the HPV status in esophageal cancer.

Human papillomavirus type-18 prevalence in oesophageal cancer in the Chinese population: a meta-analysis

Globally, the prevalence of oesophageal cancer cases is particularly high in China. Since 1982, oncogenic human papillomavirus (HPV) has been hypothesized as a risk factor for oesophageal cancer, but no firm evidence of HPV infection in oesophageal cancer has been established to date. We aimed to conduct a meta-analysis to estimate the high-risk HPV-18 prevalence of oesophageal cancer in the Chinese population. Eligible studies published from 1 January 2005 to 12 July 2014 were retrieved via computer searches of English and Chinese literature databases (including Medline, EMBASE, Chinese National Knowledge Infrastructure and Wanfang Data Knowledge Service Platform). A random-effects model was used to calculate pooled prevalence and corresponding 95% confidence intervals (CIs). A total of 2556 oesophageal cancer cases from 19 studies were included in this meta-analysis. Overall, the pooled HPV-18 prevalence in oesophageal cancer cases was 4·1% (95% CI 2·7-5·5) in China, 6·1% (95% CI 2·9-9·3) in fresh or frozen biopsies and 4·0% (95% CI 2·3-5·8) in paraffin-embedded fixed biopsies, 8·2% (95% CI 4·6-11·7) by the E6/E7 region and 2·2% (95% CI 0·9-3·6) by the L1 region of the HPV gene. This meta-analysis indicated that China has a moderate HPV-18 prevalence of oesophageal cancer compared to cervical cancer, although there is variation between different variables. Further studies are needed to elucidate the role of HPV in oesophagus carcinogenesis with careful consideration of study design and laboratory detection method, providing more accurate assessment of HPV status in oesophageal cancer.

Transmission of genital human papillomavirus infection in couples: a population-based cohort study in rural China

HPV transmission dynamics have rarely been studied in the general population, especially in China. We followed the genital HPV infection status of both partners in 874 couples aged 25-65 years from rural China for up to 7 bi-annual visits during 2009-2013. The positive HPV concordance and transmission rate for partners in a couple were evaluated and relevant risk factors were assessed. The concordance of any, oncogenic, and non-oncogenic HPV was 15.52%, 16.18% and 10.41%, respectively. Male-to-female transmission rate was 7.11, 12.13 and 4.77/1000 person months for any, oncogenic and non-oncogenic HPV respectively. The female-to-male transmission rate was 5.56, 2.37, and 17.01/1000 person months for any, oncogenic and non-oncogenic HPV respectively. The risk of male-to-female transmission was significantly higher than that of female-to-male transmission for oncogenic types. However, for non-oncogenic types, the risk of male-to-female transmission was significantly lower than that of female-to-male transmission. Younger couples, persistent infection with HPV, higher numbers of sexual partners and higher frequency of sexual intercourse were positively associated with HPV transmission in couples. Our results indicate that men in rural China play a more important role than men in western populations as a source of cervical oncogenic HPV infection in women.

Viruses, Other Pathogenic Microorganisms and Esophageal Cancer

BACKGROUND

Esophageal cancer (EC) is the eighth most prevalent malignant tumor and the sixth leading cause of cancer mortality throughout the world. Despite the technical developments in diagnosis and treatment, the 5-year survival rate is still low. The etiology of EC remains poorly understood; multiple risk factors may be involved and account for the great variation in EC incidence in different geographic regions.

SUMMARY

Infection with carcinogenetic pathogens has been proposed as a risk factor for EC. This review explores the recent studies on the association of human papillomavirus (HPV), Epstein-Barr virus (EBV), Helicobacter pylori and esophageal bacterial biota with EC.

KEY MESSAGE

Among the above-mentioned pathogens, HPV most likely contributes to esophageal squamous cell carcinoma (ESCC) in high-risk populations. New techniques are being applied to studies on the role of infection in EC, which will inevitably bring novel ideas to the field in the near future.

PRACTICAL IMPLICATIONS

Multiple meta-analyses support the finding of a higher HPV detection rate in regions associated with high risk for ESCC compared to low-risk areas. A potential role of HPV in the rise of esophageal adenocarcinoma (EAC) was proposed recently. However, further studies are required before a firm conclusion can be drawn. Less work has been done in studying the association between EBV and ESCC, and the results are quite controversial. H. pylori infection is found to be inversely related to EC, which is probably due to the reduced incidence of gastroesophageal reflux disease. Analysis of the esophageal bacterial biota revealed distinct clusters of bacteria in normal and diseased esophagi. A type II microbiome rich in Gram-negative bacteria potentially contributes to EAC by inducing chronic inflammation. Novel findings from such studies as these may benefit public health by justifying anti-infection measures to prevent EC.

Conization as a marker of persistent cervical human papillomavirus (HPV) infection and risk of gastrointestinal cancer: a Danish 34-year nationwide cohort study

PURPOSE

Persistent cervical infection with human papillomavirus (HPV) may be a marker of poor immune function and thus associated with an increased cancer risk. HPV infection is implicated in all cases of cervical cancer, but except for anal and esophageal cancers, the association between persistent HPV infection and gastrointestinal cancer has not been investigated.

METHODS

We performed a nationwide population-based cohort study of 83,008 women undergoing cervical conization between 1978 and 2011, using cervical conization as a marker of chronic HPV infection. We computed standardized incidence ratios (SIRs) as a measure of the relative risk of each cancer comparing women undergoing conization with that expected in the general population. We also calculated absolute risks.

RESULTS

During follow-up, 988 GI cancers occurred versus 880 expected among 83,008 women followed for a median of 14.9 years, corresponding to a SIR of 1.1 (95 % CI 1.1-1.2). Risks were increased for anal (SIR 2.9; 95 % CI 2.3-3.5) and esophageal (SIR 1.5; 95 % CI 1.1-2.0) cancers, with suggested increased risks of cancers of the gallbladder and biliary tract (SIR 1.3; 95 % CI 0.90-1.8), pancreas (SIR 1.2; 95 % CI 0.97-1.4), and liver (SIR 1.1; 95 % CI 0.79-1.6). The SIRs decreased with increasing follow-up time. The risks of gastric, small intestinal, colon, or rectal cancers were not elevated. Overall, the absolute cancer risk was 0.18 % (95 % CI 0.15-0.21) after 5 years.

CONCLUSIONS

The relative risks of several gastrointestinal cancers were raised among women who underwent cervical conization for persistent HPV infection, but the absolute risks were low.

Microbiome, innate immunity, and esophageal adenocarcinoma

With the development of culture-independent technique, a complex microbiome has been established and described in the distal esophagus. The incidence of esophageal adenocarcinoma (EAC) has increased dramatically in the United States. Studies documenting an altered microbiome associated with EAC and its precedents suggest that dysbiosis may be contributing to carcinogenesis, potentially mediated by interactions with toll-like receptors. Investigations attempting to associate viruses with EAC have not been as consistent. Currently available data are cross-sectional and therefore cannot prove causal relationships. Prospectively, microbiome studies open a new avenue to the understanding of the etiology and pathogenesis of reflux disorders and EAC.

miR-101 suppresses tumor proliferation and migration, and induces apoptosis by targeting EZH2 in esophageal cancer cells

AIM

To investigate the role of miR-101 in the regulation of tumor proliferation, invasion, apoptosis and to its target gene in human ESCC.

METHODS

The expression level of miR-101 in Eca109 cell line was determined by real-time polymerase chain reaction (PCR). After transfected with miR-101 mimics and inhibitor, proliferation, migration and apoptosis in ESCC cell line (Eca109) were detected by MTT, cell wound healing assay and flow cytometry, respectively. The expression of EZH2 in Eca109 cell was examined by immunohistochemical staining.

RESULTS

We found that miR-101 was significantly down-regulated in ESCC cell than in matched normal esophageal epithelium cell. The expression level of miR-101 was inversely correlated to EZH2 protein expression in ESCC cell. In Eca109 cells, over-expression of miR-101 significantly inhibited the migration and invasion of ESCC cells, and promotes cell apoptosis.

CONCLUSIONS

These findings suggest that decreased expression of miR-101 might promote metastasis of human ESCC by inducing accumulation of EZH2 protein.

Epigenetic pathogenesis of human papillomavirus in upper aerodigestive tract cancers

Human papillomavirus (HPV) has been recently associated with squamous cell carcinoma of upper aerodigestive tract (SCC of UADT), but its possible role in promoting aberrant methylation in these tumors has largely remained unexplored. Herein, we investigated the association of HPV with aberrant methylation in tumor-related genes/loci consisting of the classical CpG Island Methylator Phenotype (CIMP) panel markers (p16, MLH1, MINT1, MINT2, and MINT31) and other frequently methylated cancer-related genes (DAPK1, GSTP1, BRCA1, ECAD, and RASSF1) and survival of UDAT cancers. The study includes 219 SCC of UADT patients from different hospitals of Northeast India. Detection of HPV and aberrant promoter methylation was performed by PCR and Methylation Specific PCR respectively. Association study was conducted by Logistic regression analysis and overall survival analysis was done by Kaplan-Meier plot. HPV was detected in 37% of cases, with HPV-18 as the major high-risk sub-type. Although HPV presence did not seem to affect survival in overall UADT cancers, but was associated with a favourable prognosis in head and neck squamous cell carcinoma. Hierarchical clustering revealed three distinct clusters with different methylation profile and HPV presence. Among these, the CIMP-high subgroup exhibited the highest HPV positive cases (66%). Furthermore, multivariate analysis revealed a strong synergistic association of HPV and tobacco towards modulating promoter hypermethylation in UADT cancer (OR = 27.50 [95% CI = 11.51-88.03] for CIMP-high vs. CIMP-low). The present study proposes a potential role of HPV in impelling aberrant methylation in specific tumor related loci, which might contribute in the initiation and progression of SCC of UADT.

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.

High-risk human papillomavirus infection associated with telomere elongation in patients with esophageal squamous cell carcinoma with poor prognosis

BACKGROUND

Telomere maintenance is crucial in carcinogenesis and tumor progression. The results of a previous study from the authors indicated that infection with high-risk human papillomavirus (HR-HPV) types 16, 18, and 58 was a risk factor for esophageal squamous cell carcinoma (ESCC) in the Shantou region of China. In the current study, the authors explored the association between HR-HPV infection, telomere length (TL), and DNA methylation and their significance in the prognosis of patients with ESCC.

METHODS

TL and DNA methylation were analyzed by real-time polymerase chain reaction and methylation-specific polymerase chain reaction in 70 cases of ESCC tumor (T) and paired nontumor (NT) tissues and 50 cases of normal esophagus (NE). The prognostic value of TL and DNA methylation in ESCC was analyzed.

RESULTS

TL gradually decreased from NE to NT to T tissue. TL in tumor tissue (T-TL) was found to be longer in tissue that was positive for HR-HPV compared with negative tissue and was found to be positively associated with viral load (Spearman correlation, 0.410; P = .037) and integration (represented by the ratio of HR-HPV E2 to E6/E7 genes; P = .01). The DNA methylation ratio of human telomerase reverse transcriptase was more prevalent with long (≥ 0.7) compared with short (< 0.7) T-TL and was positively correlated with T-TL (Spearman correlation, 0.318; P = .007) and HR-HPV integration (P = .036). Furthermore, Cox proportional hazards modeling revealed a high ratio of T-TL to NT-TL (≥ 0.80) as a factor of poor prognosis, independent of other clinicopathologic variables.

CONCLUSIONS

HR-HPV infection and integration related to telomere elongation and DNA methylation of human telomerase reverse transcriptase may be a potential biomarker of prognosis in patients with ESCC.

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.

An evaluation of SOX2 and hTERC gene amplifications as screening markers in oral and oropharyngeal squamous cell carcinomas

Background

Oral and oropharyngeal squamous cell carcinomas (OSCC) are among the most common cancers. The poor survival rate among oral cancer patients can be attributed to several factors, one of them being lack of early detection. A key approach to this problem would be to detect potentially malignant lesion at their early stage. Using the FISH technique, oral brush cytology slides can be an easy and rapid screening approach for malignant cell detection. The present study was designed to detect hTERC and SOX2 amplifications in OSSC exfoliative tumor cells and evaluate whether those two gene amplifications might serve as a supportive biomarker in early detection and diagnosis of oral and oropharyngeal SCC.

Results

Brush biopsies were collected from exophytic and exulcerated oral and oropharyngeal lesions of the oral cavity of 71 patients and 22 healthy controls. FISH techniques using a TERC-specific DNA probe and a SOX2 DNA specific probe both combined with a centromere 3-specific control probe was performed on the cytology slides. A 100 squamous epithelial cell nuclei of the smears per slide were analysed. As abnormal FISH pattern were considered amplified and polyploid patterns.

From 71 brush biopsies of oropharynx and other locations in oral cavity analysed by FISH 49 were considered to be abnormal (69%). The over representation of polyploidy and/or TERC/SOX2 amplification in tumour samples was statistically significant when compared to controls (p = 0.01).

Conclusion

SOX2 and TERC gene amplifications are common in all squamous cell carcinomas and their detection in early stages could be crucial for early detection and more accurate prognosis. Our study strongly suggests that early detection by FISH on cytobrushed samples could be a possible non-invasive screening method even before a tissue biopsy is performed.

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.

Overexpression of HLA-G Is positively associated with Kazakh esophageal squamous cell carcinoma in Xinjiang, China

HLA-G is a class I HLA that has gained much attention due to its multiple functions in the immune system. More important, some studies found HLA-G may be detrimental in tumors and viral infections, and the detection of HLA-G expression might serve as a clinical marker in the prediction of clinical outcomes for certain types of carcinoma. We assessed the association between the development of Kazakh esophageal squamous cell carcinoma (ESCC) harboring high-risk HPV infection and the expression of HLA-G. The expression of HLA-G was detected by S-P immunohistochemical staining in 60 cases of Kazakh ESCC tissues and 40 cases of Kazakh tumor adjacent normal tissues. HPV16 infection in ESCC was detected by genotype-specific polymerase chain reaction. HPV16 infection rate in Kazakh ESCC was 35.0%, significantly higher than that of the infection rate of the adjacent normal tissues 15% (p<0.05, OR=3.051; 95% CI: 1.103-8.438). The expression of HLA-G in Kazakh ESCC was 75.0% (45/60), significantly higher than that of tumor adjacent normal tissues (17.5%; p<0.05); expression of HLA-G was slightly higher in HPV16-positive than HPV16-negative ESCC, but the difference was not statistically significant (p>0.05). The positive expression rate of HLA-G was closely related to depth of invasion and clinical stage (p<0.05 for all), but was not related to age, sex, tumor location, histologic grade, and nodal status (p>0.05 for all). Overexpression of HLA-G was a characteristic feature of Kazakh ESCC; HLA-G may be involved in Kazakh ESCC carcinogenesis and HPV infection.

Role of human papillomaviruses in esophageal carcinoma: an updated systematic review from 1982 to 2013

ABSTRACT: 

Tobacco, alcohol and betel quid are known etiological agents of esophageal squamous cell carcinoma (ESCC). A meta-analysis in 2012 and a literature update (1982–August 2013) identified 159 studies with a total of 11,310 ESCCs tested for the presence of human papillomaviruses (HPVs). HPV DNA was present in 30.3% of fESCCs, with substantial geographic differences. A recent meta-analysis of 21 case–control studies investigating the HPV–ESCC association showed that HPVs increase the risk of ESCC at least threefold. Vaccine-preventable HPV-16 and HPV-18 are the most commonly identified HPV types in ESCC in both low- and high-incidence settings. HPVs should now be seriously considered as etiological agents for at least a subset of ESCC, and more studies are needed to provide conclusive evidence that HPVs cause ESCC.

Anti-HPV-E7 seropositivity and risk of esophageal squamous cell carcinoma in a high-risk population in China

Results of previous serologic studies on the association of human papillomavirus (HPV) with esophageal squamous cell carcinoma (ESCC) have been inconsistent. From 2007 to 2010, the authors collected blood samples and relevant demographic data from 1435 patients with ESCC and 2071 age- and sex-matched normal controls from Anyang, China. HPV-16, 18 and 57 E7 antibodies were evaluated with the glutathione-S-transferase capture ELISA. The proportions of subjects who were positive for antibodies against these three HPV antigens in the case group were all significantly higher than those in the control group. In multivariate analysis, the presence of HPV-16 E7 antibody was associated with an increased risk of ESCC [odds ratio (OR) = 3.6, 95% confidence interval (CI): 2.5-5.0], whereas the presence of HPV-18 (OR = 1.1, 95% CI: 0.7-1.7) and HPV-57 (OR = 1.3, 95% CI: 0.9-1.9) antibodies were not significant after adjustment for HPV-16. In multiple cutoff value analysis, the lowest OR for HPV-16 was obtained with the standard cut point mean + 3 SD. This study provides serological evidence in support of HPV-16 infection playing a role in the occurrence of ESCC in a high-incidence area of China.

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.

Clinical significance of combined detection of human papilloma virus infection and human telomerase RNA component gene amplification in patients with squamous cell carcinoma of the esophagus in northern China

Background

The aim of the study was to test for human papilloma virus (HPV) infection and human telomerase RNA component (hTERC) gene amplification in tissues derived from esophageal cancer, in esophagus displaying atypical hyperplasia and in normal tissue, and to analyze the relationship between them and discuss whether HPV infection and hTERC gene amplification play a role in the duration of survival of esophageal cancer patients.

Methods

To test for HPV infection, surface plasma resonance was used after extracting and subjecting the DNA to PCR amplification. Measurement of hTERC gene amplification was performed by the fluorescence in situ hybridization technique.

Results

The rates of HPV infection in the normal group, the atypical esophageal hyperplasia group and the cancer group were 0% (0/40), 10.00% (1/10) and 20.65% (19/92), respectively, with a statistically significant difference of P < 0.01. The hTERC gene amplification rate in normal tissue, grade I atypical hyperplastic tissue, grade II/III atypical hyperplastic tissue and esophageal cancer tissue were 0% (0/89), 15.38% (4/26), 47.06% (8/17) and 89.13% (82/92), respectively, with a statistically significant difference of P < 0.01. On follow-up of 92 patients, survival curves of the HPV-positive and HPV-negative groups were not significantly different (P > 0.05). Survival curves of the hTERC gene amplification-positive and hTERC gene amplification-negative groups were statistically significant (P < 0.05). A matching chi-square test showed that there was no correlation between HPV infection and hTERC gene amplification (P > 0.05).

Conclusion

HPV infection may be one of many factors contributing to the development of esophageal cancer, but it does not influence prognosis. Amplification of the hTERC gene appears to influence certain features associated with postoperative survival in esophageal carcinoma patients.

Amplification of the telomerase RNA component gene as a new genetic marker for disease progression and prognosis in esophageal squamous cell carcinoma

Amplification of the human telomerase RNA component (TERC) gene was found in esophageal squamous cell carcinoma (ESCC). However, its roles in the progression and prognosis of ESCC have not been well understood. The amplification of TERC in normal mucosa, low-grade and high-grade intraepithelial neoplasia, and invasive ESCC samples were evaluated using a fluorescence in situ hybridization assay. The amplification of TERC invariably occurred in high-grade intraepithelial neoplasia and invasive ESCC, partially occurred in low-grade intraepithelial neoplasia specimens, and seldom occurred in normal mucosa. The average signal ratio of TERC to chromosome 3 centromere-specific probe (TERC/CSP3) was 1.00 ± 0.01 (average ± standard deviation) in normal mucosas, 1.01 ± 0.08 in low-grade intraepithelial neoplasias, 1.39 ± 0.26 in high-grade intraepithelial neoplasias, and 1.56 ± 0.41 in invasive ESCC. High TERC/CSP3 ratio was positively associated with lymph node metastasis (P = 0.005) and advanced tumor stage (P = 0.045). Patients with high amplification of TERC had poor survival (P = 0.01). The amplification of TERC could be used as a new genomic marker for disease progression and prognosis of ESCC. The amplified TERC gene may be a potential therapeutic target for ESCC.

Human papillomavirus type 16 infection may be involved in esophageal squamous cell carcinoma carcinogenesis in Chinese Kazakh patients

The aim of this study was to investigate human papillomavirus type 16 (HPV16) prevalence in esophageal squamous cell carcinoma (ESCC) in Xinjiang Kazakh patients and its role in ESCC carcinogenesis. One hundred and fifty cases of ESCC and 150 cases of corresponding normal esophageal mucosa (CNGM) samples were collected from north Xinjiang where the Kazakh ethnic group has lived since ancient times. HPV16 infection in ESCC and CNGM was detected by genotype-specific polymerase chain reaction. HPV16 DNA was detected in 55 of 150 ESCC samples (36.7%) and 24 of 150 corresponding normal esophageal mucosa samples (16%) with significant differences (P < 0.001, odds ratio = 3.039, 95% confidence interval: 1.756-5.260). No statistically significant correlations were found between HPV16 infection and the age or gender of patients, tumor site, tumor cell differentiation, or lymph node metastasis (P > 0.05). HPV16 infection is common in cases of ESCC in the Kazakh ethnic group in Xinjiang and may be involved in ESCC carcinogenesis.