Infection and esophageal cancer

Immuno-genomic analysis reveals eosinophilic feature and favorable prognosis of female non-smoking esophageal squamous cell carcinomas

Most of esophageal squamous cell carcinoma (ESCC) develop in smoking males in Japan, but the genomic etiology and immunological characteristics of rare non-smoking female ECSS remain unclear. To elucidate the genomic and immunological features of ESCC in non-smoking females, we analyzed whole-genome or transcriptome sequencing data from 94 ESCCs, including 20 rare non-smoking female cases. In addition, 31,611 immune cells were extracted from four ESCC tissues and subject to single-cell RNA-seq. We compared their immuno-genomic and microbiome profiles between non-smoking female and smoking ESCCs. Non-smoking females showed much better prognosis. Whole-genome sequencing analysis showed no significant differences in driver genes or copy number alterations depending on smoking status. The mutational signatures specifically observed in non-smoking females ESCC could be attributed to aging. Immune profiling from RNA-seq revealed that ESCC in non-smoking females had high tumor microenvironment signatures and a high abundance of eosinophils with a favorable prognosis. Single-cell RNA-sequencing of intratumor immune cells revealed gender differences of eosinophils and their activation in female cases. ESCCs in non-smoking females have age-related mutational signatures and gender-specific tumor immune environment with eosinophils, which is likely to contribute to their favorable prognosis.

Viral Pathogens in Oesophageal and Gastric Cancer

Tumour virology was born with the discovery by Peyton Rous in 1911 of a filterable agent in chicken cellular extracts that caused neoplasia in healthy chickens. Universally, 20% of all human cancers have a viral aetiology. Viruses are involved at various stages of the carcinogenesis pathway, depending on the viral pathogen, and likely require co-factors. Multiple risk factors have been associated with oesophageal and gastric malignancy, including carcinogenic pathogens. These viruses and bacteria include human papillomavirus (HPV) [oesophageal cancer], Epstein-Barr virus (EBV) [proximal stomach cancer], and Helicobacter pylori (HP) [non-cardia stomach cancer]. Viruses such as EBV have been firmly established as causal for up to 10% of gastric cancers. HPV is associated with 13 to 35% of oesophageal adenocarcinoma but its role is unclear in oesophageal squamous cell carcinomas. The causal relationship between hepatitis B (HBV), cytomegalovirus (CMV), HPV, and John Cunningham (JCV) and gastric neoplasia remains indeterminate and warrants further study. The expression of viral antigens by human tumours offers preventive and therapeutic potential (including vaccination) and has already been harnessed with vaccines for HPV and HBV. Future goals include viral protein-based immunotherapy and monoclonal antibodies for the treatment of some of the subset of EBV and HPV-induced gastro-esophageal cancers.

PolyC-RNA-binding protein 1 (PCBP1) enhances tropomyosin 3 (TPM3) mRNA stability to promote the progression of esophageal squamous cell carcinoma

The molecular etiology of esophageal squamous cell carcinoma (ESCC) has not been fully elucidated. Understanding the molecular mechanisms and finding new therapeutic targets for ESCC are of crucial importance. PolyC-RNA-binding protein 1 (PCBP1) is an RNA-binding protein. Here, we found overexpressed PCBP1 in esophageal cancer tissues by quantitative polymerase chain reaction (qPCR) and western blotting analysis. PCBP1 knockdown significantly attenuated migratory and invasion abilities of ESCC cells. Mechanistically, PCBP1 bound directly to tropomyosin 3 (TPM3) mRNA, which was verified by RNA–protein immunoprecipitation (RIP) assay. PCBP1 knockdown markedly reduced messenger RNA (mRNA) levels of TPM3. After inhibiting intracellular mRNA synthesis with actinomycin D (ActD), it was found that PCBP1 knockdown contributed to a significant decrease in TPM3 mRNA degradation. Furthermore, PCBP1 promoted migration and invasion of EC cells by directly binding to the 3’UTR of TPM3 mRNA, increasing TPM3 mRNA stability. Taken together, PCBP1 acting as a pro-oncogenic factor enhances TPM3 mRNA stability by directly binding to the 3’UTR of TPM3 mRNA in esophageal squamous cell carcinoma. Our findings provide a new perspective for understanding the molecular mechanism of esophageal carcinogenesis, and PCBP1 is a promising therapeutic target.

LINC00958 promotes proliferation, migration, invasion, and epithelial-mesenchymal transition of oesophageal squamous cell carcinoma cells

Oesophageal cancer is one of the deadliest cancers in the world. Oesophageal squamous cell carcinoma (ESCC) is the most prevalent histological type of oesophageal cancer. Oesophageal cancer has a poor prognosis because of its invasiveness. Thus, it is especially important to seek effective treatment methods. Research indicates that long non-coding RNAs (lncRNAs) play a significant role in the occurrence and development of oesophageal cancer. The aim of this study was to describe the role of LINC00958 in ESCC. Bioinformatics and real-time quantitative polymerase chain reaction (RT-qPCR) methods were utilized to predict and verify the expression of LINC00958 in ESCC. Related functional experiments, including cell proliferation, migration and invasion, were performed. In addition, a western blot and a dual luciferase reporter gene experiment were used to study the detailed carcinogenic mechanism of LINC00958. The results indicated there was a high expression of LINC00958 in ESCC, which promoted proliferation, migration, invasion and Epithelial–Mesenchymal Transition (EMT) of ESCC cells, and this effect may be via regulating miR-510-5p.

Importance of investigating high-risk human papillomavirus in lymph node metastasis of esophageal adenocarcinoma

High-risk human papillomavirus has been suggested as a risk factor for esophageal adenocarcinoma. Tumor human papillomavirus status has been reported to confer a favorable prognosis in esophageal adenocarcinoma. The size of the primary tumor and degree of lymphatic spread determines the prognosis of esophageal carcinomas. Lymph node status has been found to be a predictor of recurrent disease as well as 5-year survival in esophageal malignancies. In human papillomavirus driven cancers, e.g. cervical, anogenital, head and neck cancers, associated lymph nodes with a high viral load suggest metastatic lymph node involvement. Thus, human papillomavirus could potentially be useful as a marker of micro-metastases. To date, there have been no reported studies regarding human papillomavirus involvement in lymph nodes of metastatic esophageal adenocarcinoma. This review highlights the importance of investigating human papillomavirus in lymph node metastasis of esophageal adenocarcinoma based on data derived from other human papillomavirus driven cancers.

FGF2, an Immunomodulatory Factor in Asthma and Chronic Obstructive Pulmonary Disease (COPD)

The fibroblast growth factor 2 (FGF2) is a potent mitogenic factor belonging to the FGF family. It plays a role in airway remodeling associated with chronic inflammatory airway diseases, including asthma and chronic obstructive pulmonary disease (COPD). Recently, research interest has been raised in the immunomodulatory function of FGF2 in asthma and COPD, through its involvement in not only the regulation of inflammatory cells but also its participation as a mediator between immune cells and airway structural cells. Herein, this review provides the current knowledge on the biology of FGF2, its expression pattern in asthma and COPD patients, and its role as an immunomodulatory factor. The potential that FGF2 is involved in regulating inflammation indicates that FGF2 could be a therapeutic target for chronic inflammatory diseases.

Risk Factors Associated with Precancerous Lesions of Esophageal Squamous Cell Carcinoma: a Screening Study in a High Risk Chinese Population

Background: Esophageal squamous cell carcinoma (ESCC) has been having a high mortality rate in China. Most patients are diagnosed in advanced stages, leading to the poor prognosis and low 5-year survival rate. Detection of precancerous lesions or early cancers is the key to improving this situation. Although previous studies have identified some risk factors for ESCC, they rarely paid attention to the premalignant esophageal lesions. We thus initiated a population-based screening study aiming to assess risk factors associated with esophageal precancerous lesions (EPLs) in a high risk Chinese population. Methods: From September 2013 to July 2015, we screened residents aged 40-69 years from 53 randomly selected communities in Feicheng, China (n = 5076). Each participant went through questionnaire interview, physical examination, endoscopy and biopsy. Using logistic regression, we compared participants with EPLs to that with normal esophageal mucosa for finding potential risk factors of EPLs. Results: A total of 570 participants were diagnosed with EPLs. We observed no association between EPLs and tobacco smoking or alcohol consumption in unadjusted or adjusted model. In the adjusted model, the OR (95% CI) was 1.84 (1.18-2.89) for people of drinking shallow-well water comparing to people who was drinking tap-water. In a comparison of participants with good oral health, the ESD/ESCC ORs (95% CI) for those with very poor or poor oral health, were 1.78 (1.28-2.49) and 1.58 (1.16-2.15) respectively. However, no statistical significance was observed after adjustment. Moreover, cereal straw heating (OR= 1.74, 95% CI: 0.90-3.36, P=0.099) may lead to increased risk of EPLs. Conclusion: In Feicheng population, tobacco smoking or alcohol consumption may not be risk factors of EPLs. Low-quality drinking water raised the EPLs risk. Bad house heating materials, such as cereal straw, may lead to high EPLs risk.

Progress in characterizing the linkage between Fusobacterium nucleatum and gastrointestinal cancer

Microbiome research is a rapidly advancing field in human cancers. Fusobacterium nucleatum is an oral bacterium, indigenous to the human oral cavity, that plays a role in periodontal disease. Recent studies have found that F. nucleatum can promote gastrointestinal tumor progression and affect the prognosis of the disease. In addition, F. nucleatum may contribute to the chemo-resistance of gastrointestinal cancers. This review summarizes recent progress in the pathogenesis of F. nucleatum and its impact on gastrointestinal cancer.

Achalasia and esophageal cancer: risks and links

Esophageal cancer affects more than 4,50,000 persons worldwide, and its incidence has increased in recent years. It is the eighth most common cancer across the globe. The main histologic types are esophageal squamous cell carcinoma (ESCC) and esophageal adenocarcinoma (EA), and their associated risk factors are well known. Achalasia, an idiopathic esophageal disorder that conditions aperistalsis and the absence of lower esophageal sphincter relaxation, stands out among them. The prevalence of ESCC in subjects with esophageal achalasia is 26 in every 1,000 cases, whereas the prevalence of EA is 4 in every 1,000. Patients with achalasia have a 50 times higher risk of presenting with ESCC than the general population, and the disease manifests 20-25 years after achalasia symptom onset. Multiple mechanisms are related to the development of ESCC in achalasia, and they include bacterial overgrowth, food stasis, genetic alterations, and chronic inflammation. Regarding the risk of EA in achalasia patients, most cases are associated with Barrett's esophagus, due to uncontrolled chronic acid reflux. Given that achalasia is a well-established factor for ESCC/EA, clinicians must be aware of said associations to enable the development of programs for the prevention and opportune detection of these cancers in patients with achalasia.

A viral map of gastrointestinal cancers

Cancers of the gastrointestinal tract (GIT) are expected to account for approximately 20% of all cancers in 2017. Apart from their high incidence, GIT cancers show high mortality rates, placing these malignancies among the most prominent public health issues of our time. Cancers of the GIT are the result of a complex interplay between host genetic factors and environmental factors and frequently arise in the context of a continued active inflammatory response. Several tumor viruses are able to elicit such chronic inflammatory responses. In fact, several viruses have an impact on GIT tumor initiation and progression, as well as on patients' response to therapy and prognosis, through direct and indirect mechanisms. In this review, we have gathered information on different viruses' rates of infection, viral-driven specific carcinogenesis mechanisms and viral-related impact on the prognosis of cancers of the GIT (specifically in organs that have an interface with the environment - esophagus, stomach, intestines and anus). Overall, while some viral infections show a strong causal relation with specific gastrointestinal cancers, these represent a relatively small fraction of GIT malignancies. Other types of cancer, like Esophageal Squamous Cell Carcinoma, require further studies to confirm the carcinogenic role of some viral agents.

Worldwide incidence, mortality and time trends for cancer of the oesophagus. Eur J Cancer Prev. 2017;26:107-118. [PMID: 27014938 DOI: 10.1097/cej.0000000000000249]

The incidence and mortality trends of oesophageal cancer are changing significantly across the world with considerable heterogeneity between sex, histological types, ethnic patterns and geographical distribution. Recent oesophageal cancer incidence and mortality trends have been analysed using data available from the WHO mortality database, the GLOBOCAN 2012 database and the Cancer Incidence in Five Continents database managed by the International Agency for Research on Cancer. Huge geographical variation is an epidemiological characteristic of oesophageal cancer, with the highest incidence rates observed in Eastern Asia and in Eastern and Southern Africa and the lowest rates observed in Western Africa. The variation is to the order of more than 21 times between the lowest-incidence and the highest-incidence countries. Although the incidence of squamous cell carcinoma is increasing globally, its incidence rates are decreasing in the USA and a few European countries. However, the decrease in the incidence of squamous cell carcinomas in these countries has been accompanied by a marked increase in adenocarcinoma incidence rates. There is a significant sex variation as well, with men being affected three to four times more commonly than women worldwide. The observed trends reflect significant global variations in the incidence and mortality of oesophageal cancers on the basis of sex, geographical distribution, ethnicity and histology. These epidemiological factors related to oesophageal cancers point out a possibly significant role of molecular epidemiological factors (genetic susceptibility and response to treatment) with major differences likely between the characteristics of Asian and Western populations.

Role of viruses in gastrointestinal cancer

Gastrointestinal cancers are a global public health problem, which represent a vast majority of all cancer-caused deaths in both men and women. On the other hand, viral pathogens have been long implicated as etiological factors in the onset of certain human cancers, including gastrointestinal tumors. In this regard, Human Papilloma Virus (HPV), Epstein-Barr Virus (EBV), and John Cunningham Virus (JCV) have been more strongly suggested to be involved in gastrointestinal carcinogenesis; so that, the association of HPV with oropharyngeal and anal cancers and also the association of EBV with gastric cancer have been etiologically confirmed by epidemiological and experimental investigations. Although, the association of other viruses is less evident, but may rely on co-factors for their oncogenic roles. Therefore, to improve the prevention and treatment of these classes of cancer, their association with viral agents as potential risk factors should be investigated with care. In this respect, the present review has focused on the existing literature on the subject of viral involvement in gastrointestinal tumorgenesis, by covering and discussing various gastrointestinal cancers, corresponding viral agents and their oncogenic aspects and then summarizing evidences either supporting or rejecting a causal role of these pathogens in gastrointestinal malignancies.

Metformin and esophageal cancer risk in Taiwanese patients with type 2 diabetes mellitus

This study evaluated whether metformin might reduce esophageal cancer risk. Patients with type 2 diabetes mellitus diagnosed during 1999–2005 were recruited from the reimbursement database of Taiwan's National Health Insurance. Those newly treated with metformin (n = 288013, “ever users of metformin”) or other antidiabetic drugs (n = 16216, “never users of metformin”) were followed until December 31, 2011. Sensitivity analyses were conducted in a matched-pair sample of 16216 never users and 16216 ever users. Hazard ratios were estimated by Cox regression incorporated with the inverse probability of treatment weighting using propensity score. The risk associated with infection of Helicobacter pylori, Epstein-Barr virus, hepatitis B virus and hepatitis C virus was also evaluated. Results showed that the incidence of esophageal cancer in ever and never users was 25.03 and 50.87 per 100,000 person-years, respectively. The overall hazard ratio (95% confidence intervals) of 0.487 (0.347–0.684) suggested a significantly lower risk among metformin users. Hazard ratios comparing the first (< 21.47 months), second (21.47–46.00 months) and third (> 46.00 months) tertile of cumulative duration of metformin use to never users was 1.184 (0.834–1.680), 0.403 (0.276–0.588) and 0.113 (0.071–0.179), respectively. Infection of Helicobacter pylori (but not the other viral infections) significantly increased the risk, which could be ameliorated by metformin. Analyses in the matched sample consistently supported a protective role of metformin. In conclusion, metformin reduces esophageal cancer risk when the cumulative duration is more than approximately 2 years.

Different frequencies of Porphyromonas gingivalis infection in cancers of the upper digestive tract

The high incidence rate of multiple carcinomas in the upper digestive tract is often explained in terms of involvement of the same underlying risk factors. It has been reported that the oral bacterium Streptococcus anginosus is associated with esophageal, gastric, and pharyngeal cancers. We previously reported occurrence of Porphyromonas gingivalis (P. gingivalis) DNA in esophagus cancer. In this study, the presence of P. gingivalis in specimens of various types of cancer from the upper digestive tract was investigated. Here we report that P. gingivalis was preferentially and frequently present in specimens of esophageal cancer as well as in those from dysplasia of the esophagus but rarely in matched noncancerous portions and are quite low or absent in cancers from the cardia or stomach. Therefore, it led us to propose that, the microorganism does not survive in conditions of high acidity. We then investigate the pH dependence of survival of P. gingivalis as well as the acid tolerance of it. We found that, exposure to acidic buffers of a wide range of pH values led to a decline in colony forming units of P. gingivalis, thus, providing a possible explanation for variations in frequencies of P. gingivalis infection in this study.

Review of the gut microbiome and esophageal cancer: Pathogenesis and potential clinical implications

Esophageal cancer ranks among the most aggressive malignant diseases. The limited improvements in treatment outcomes provided by conventional therapies have prompted us to seek innovative strategies for treating this cancer. More than 100 trillion microorganisms inhabit the human intestinal tract and play a crucial role in health and disease conditions, including cancer. The human intestinal microbiome is thought to influence tumor development and progression in the gastrointestinal tract by various mechanisms. For example, Fusobacterium nucleatum, which primarily inhabits the oral cavity and causes periodontal disease, might contribute to aggressive tumor behavior through activation of chemokines such as CCL20 in esophageal cancer tissue. Composition of the intestinal microbiota is influenced by diet, lifestyle, antibiotics, and pro- and prebiotics. Therefore, by better understanding how the bacterial microbiota contributes to esophageal carcinogenesis, we might develop novel cancer prevention and treatment strategies through targeting the gastrointestinal microflora. This review discusses the current knowledge, available data and information on the relationship of microbiota with esophagitis, Barrett's esophagus, esophageal adenocarcinoma and squamous cell carcinoma.

A primary esophageal MALT lymphoma patient with Helicobacter pylori infection achieved complete remission after H. pylori eradication without anti-lymphoma treatment

Primary esophageal lymphoma is an extremely rare disease. We report a 76-year-old woman with esophageal lymphoma who achieved remission after Helicobacter pylori (HP) eradication. Esophagogastroduodenoscopy (EGD) revealed a mass in the lower esophagus, and she was diagnosed with stage IE mucosa-associated lymphoid tissue (MALT) lymphoma. She rejected any anti-lymphoma treatment except for HP eradication. Follow-up EGD demonstrated the disappearance of the esophageal MALT lymphoma 2 months after HP eradication, and she remained in remission for more than 3 years. Our results demonstrate that HP eradication may be effective as initial therapy in primary esophageal MALT lymphoma patients with HP infection.

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.

Drinking water: a risk factor for high incidence of esophageal cancer in Anyang, China

Anyang is known to be a high-incidence area of esophageal cancer (EC) in China. Among a long list of risk factors, the quality of drinking water was evaluated. We have selected 3806 individuals and collected 550 drinking water samples correspondent with this not-matched case-control survey. There are 531 EC patients included based on Population Cancer Registry from 92 townships, of which 3275 controls with long-lived aged over 90 years and free from EC are used as controls in the same regions. Our result suggests that the quality of drinking water is a highly associated risk factor for EC. The residential ecological environment and the quality of water resource positively link with each other. The analysis of water samples also demonstrated that the concentrations of methyl ethylamine, morpholine, N-methylbenzylamine, nitrate and chloride in water from springs and rivers are higher than those in well and tap water (P = 0.001). Micronuclei formation tests show that well water and tap water in these regions have no mutagenicity.

Clinicopathological significance of LAT1 and ASCT2 in patients with surgically resected esophageal squamous cell carcinoma

BACKGROUND

Amino acid transporters are highly expressed in various human cancers. L-type amino acid transporter 1 (LAT1) and system alanine-serine-cysteine amino acid transporter-2 (ASCT2) play a crucial role in tumor progression and survival. However, the clinicopathological significance of these transporters in patients with esophageal squamous cell carcinoma (ESCC) remains unclear.

METHODS

One hundred and fifty-seven patients with surgically resected ESCC were evaluated. Immunohistochemical analysis was performed for LAT1, ASCT2, CD98, Ki-67, and micro-vessel density (MVD), as determined by CD34 expression.

RESULTS

LAT1 and ASCT2 were positively expressed in 59% (93/157) and 48% (76/157) of tumors respectively. LAT1 and ASCT2 expression significantly correlated with T factor, N factor, lymphatic permeation, vascular invasion, and CD98 expression. The 5-year survival rates of LAT1-high and -low and ASCT2-high and -low expressing patients were 62.0% and 69.6% (P < 0.05) and 59.6% and 70.1% (P = 0.068), respectively. The combined positive expression of LAT1 and ASCT2 was a significant prognostic factor in univariate analysis.

CONCLUSION

High expression of LAT1 and ASCT2 correlates with metastasis and invasion. Accordingly, these proteins could serve as prognostic biomarkers and therapeutic targets for treating patients with surgically resectable ESCC. J. Surg. Oncol. 2016;113:381-389. © 2016 Wiley Periodicals, Inc.

Detection of Merkel Cell Polyomavirus and Human Papillomavirus in Esophageal Squamous Cell Carcinomas and Non-Cancerous Esophageal Samples in Northern Iran

Human papillomavirus (HPV) infection is one of the hypothesized causes of esophageal squamous cell carcinoma (ESCC), but the etiological association remains uncertain. It was postulated that other infectious agents together with HPV may increase the risk of ESCC. The current investigation aimed to explore the presence of a new human tumor virus, Merkel cell polyomavirus (MCPyV), together with HPV in ESCC tumors and non-cancerous esophageal samples in northern Iran. In total, 96 esophageal samples (51 with ESCC, and 45 without esophageal malignancy) were examined. HPV DNA was detected in esophageal specimens of 16 out of the 51 ESCC cases (31.4 %) and 20 out of the 45 non-cancerous samples (44.4 %). Untypable HPV genotypes were recognized in high rates in cancerous (75.0 %) and non-cancerous (55.0 %) esophageal specimens. MCPyV DNA was detected in esophageal specimens of 23 out of the 51 ESCC cases (45.1 %) and 16 out of the 45 non-cancerous samples (35.6 %). The mean MCPyV DNA copy number was 1.0 × 10(-5) ± 2.4 × 10(-5) and 6.0 × 10(-6) ± 1.3 × 10(-5) per cell in ESCC cases and non-cancerous samples, respectively. There was no statistically significant difference between cancerous and non-cancerous samples regarding mean MCPyV DNA load (P = 0.353). A bayesian logistic regression model adjusted to the location of esophageal specimen and MCPyV infection, revealed a significant association between HPV and odds of ESCC (OR, 2.45; 95 % CI: 1.01-6.16). This study provides the evidence of the detection of the MCPyV DNA at a low viral copy number in cancerous and non- cancerous esophageal samples.

Associations of microbiota and toll-like receptor signaling pathway in esophageal adenocarcinoma

Background

Toll-like receptors (TLRs) recognize known molecules from microbes and have an established role in tumorigenesis. Using a rat model of esophageal adenocarcinoma, and human clinical samples, we investigated genes central to TLR-mediated signal transduction and characterized the esophageal microbiome across the spectrum of esophageal adenocarcinoma carcinogenesis.

Methods

We surgically induced bile/acid reflux in rats and their esophagi were harvested at 40 weeks post-surgery. Tissue samples from the model were selected for gene expression profiling. Additionally, for rat and human samples microbiome analysis was performed using PCR-ESI-MS-TOF technology with validation by fluorescence in situ hybridization.

Results

Gene expression results in the rat model indicated a significant upregulation of TLRs 1-3, 6, 7 and 9 in EAC compared to normal epithelium. PCR-ESI-MS-TOF analysis revealed a prevalence of Escherichia coli in Barrett’s esophagus (60 %) and esophageal adenocarcinoma (100 %), which was validated by fluorescence in situ hybridization. In the human clinical samples, Streptococcus pneumonia was detected in high abundance in gastroesophageal reflux disease and Barrett’s esophagus (50–70 %) in comparison to tumor adjacent normal epithelium, dysplasia, and esophageal adenocarcinoma (20–30 %). E. coli was detected in the Barrett’s esophagus and esophageal adenocarcinoma groups but was absent in the tumor adjacent normal epithelium, dysplasia, and the gastroesophageal reflux disease groups.

Conclusions

We demonstrated an association between the TLR signaling pathway and E. coli hinting towards possible early molecular changes being mediated by microbes in the rat model of esophageal adenocarcinoma carcinogenesis. Studies on human clinical samples also corroborate results to some extent; however, a study with larger sample size is needed to further explore this association.

Electronic supplementary material

The online version of this article (doi:10.1186/s12885-016-2093-8) contains supplementary material, which is available to authorized users.

Comprehensive Genomic Profiling of Advanced Esophageal Squamous Cell Carcinomas and Esophageal Adenocarcinomas Reveals Similarities and Differences

BACKGROUND

Esophageal squamous cell carcinomas (ESCCs) and esophageal adenocarcinomas (EACs) account for >95% of esophageal malignancies and represent a major global health burden. ESCC is the dominant histology globally but represents a minority of U.S. cases, with EAC accounting for the majority of U.S.

CASES

The patient outcomes for advanced ESCC and EAC are poor, and new therapeutic options are needed. Using a sensitive sequencing assay, we compared the genomic profiles of ESCC and EAC with attention to identification of therapeutically relevant genomic alterations.

METHODS

Next-generation sequencing-based comprehensive genomic profiling was performed on hybridization-captured, adaptor ligation-based libraries to a median coverage depth of >650× for all coding exons of 315 cancer-related genes plus selected introns from 28 genes frequently rearranged in cancer. Results from a single sample were evaluated for all classes of genomic alterations (GAs) including point mutations, short insertions and deletions, gene amplifications, homozygous deletions, and fusions/rearrangements. Clinically relevant genomic alterations (CRGAs) were defined as alterations linked to approved drugs and those under evaluation in mechanism-driven clinical trials.

RESULTS

There were no significant differences by sex for either tumor type, and the median age for all patients was 63 years. All ESCCs and EACs were at an advanced stage at the time of sequencing. All 71 ESCCs and 231 EACs featured GAs on profiling, with 522 GAs in ESCC (7.4 per sample) and 1,303 GAs in EAC (5.6 per sample). The frequency of clinically relevant GAs in ESCC was 94% (2.6 per sample) and 93% in EAC (2.7 per sample). CRGAs occurring more frequently in EAC included KRAS (23% EAC vs. 6% ESCC) and ERBB2 (23% EAC vs. 3% ESCC). ESCC samples were enriched for CRGA in PIK3CA (24% ESCC vs. 10% EAC), PTEN (11% ESCC vs. 4% EAC), and NOTCH1 (17% ESCC vs. 3% EAC). Other GAs that differed significantly between histologic tumor types included SMAD4 (14% EAC vs. 1% ESCC), RB1 (14% ESCC vs. 2% EAC), SOX2 (18% ESCC vs. 1% EAC), and NFE2L2 (24% ESCC vs. 1% EAC).

CONCLUSION

ESCC and EAC share similarly high frequencies of overall and clinically relevant genomic alterations; however, the profiles of genomic alterations in the two diseases differ widely, with KRAS and ERBB2 far more frequently altered in EAC compared with ESCC and with mammalian target of rapamycin (MTOR) pathway genes (PIK3CA and PTEN) and NOTCH1 more frequently altered in ESCC compared with EAC. Comprehensive genomic profiling highlights the promise of identifying clinically relevant genomic alterations in both ESCC and EAC and suggests new avenues for molecularly directed therapies in esophageal cancer.

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.

Barrett's oesophagus: can meaningful screening and surveillance guidelines be formulated based on new data and rejigging the old paradigm?

Gastro-oesophageal reflux disease (GORD) and Barrett's oesophagus (BO) have been considered to be the most important known risk factors for oesophageal adenocarcinoma (OAC). It has been the fastest growing cancer in the Western World and has occurred against a backdrop of progressive reduction in the risk estimate of malignancy associated with BO and no reduction in mortality from OAC using the prevailing screening and surveillance guidelines. The recently published link between high risk HPV and Barrett's dysplasia/cancer may be the 'missing' strong risk factor responsible for the significant rise of OAC since the 1970's, as has been the case with head and neck tumours, another viral associated cancer. P53 immunohistochemistry has been proposed as a good molecular marker for predicting disease progression in BD. Nevertheless, significant negative staining for this mutation in BD remains a major hurdle to widespread routine clinical use as a sole molecular marker. Recent data raises the distinct possibility of at least 2 (probably more) carcinogenic pathways operating in OAC. One is HPV mediated devoid largely of p53 mutations and the other p53 dependent. The joint use of both these markers as part of a molecular panel may represent the best bet yet of detecting the high risk group of progressors to OAC. Patients who are positive for either or both biomarkers i.e p53 or/and transcriptional markers of HPV may warrant more intensive screening. In future, genome wide technology may provide molecular signatures to aid diagnosis and risk stratification in BO.