Association between markers of obesity and progression from Barrett's esophagus to esophageal adenocarcinoma

Metabolic syndrome and risk of esophageal cancer by histological type: Systematic review and meta-analysis of prospective studies

BACKGROUND

Previous epidemiological studies have provided inconsistent findings regarding the association between metabolic syndrome (MetS) and risk of esophageal cancer.

METHODS

We conducted a comprehensive literature search for prospective studies in MEDLINE and EMBASE databases through April 2024. Random-effects meta-analysis was used to calculate pooled hazard ratios (HR) with 95 % confidence intervals (CI) for the associations between MetS and risk of esophageal cancer by histological type. Between-study heterogeneity was assessed by Cochran's Q test and I2 statistics.

RESULTS

Among 8097 identified studies, six studies were included. MetS was associated with an increased risk of esophageal adenocarcinoma (pooled HR=1.24; 95 %CI, 1.07-1.42; Pheterogeneity=0.392, I2=3.8 %, N = 6), but not esophageal squamous cell carcinoma (HR=0.89; 95 % CI, 0.58-1.36; Pheterogeneity=0.040, I2=68.9 %, N = 3). An increased risk of esophageal adenocarcinoma was indicated for hyperglycemia (HR= 1.14; 95 % CI, 1.01-1.29; Pheterogeneity=0.693, I2=0.0 %, N = 3) and obesity (HR=1.50; 95 % CI, 1.24-1.82; Pheterogeneity=0.191, I2=34.5 %, N = 5), rather than the other components of MetS, i.e. hypertension or levels of triglyceride or high-density lipoprotein. Hypertension was associated with seemingly increased risk of esophageal squamous cell carcinoma (HR=1.39; 95 % CI, 0.93-2.09; Pheterogeneity=0.030, I2=71.4 %, N = 3), while obesity was associated with a decreased risk (HR=0.65; 95 % CI, 0.38-1.12; Pheterogeneity=0.009, I2=78.7 %, N = 3); no associations were observed for the other components of MetS with esophageal squamous cell carcinoma.

CONCLUSIONS

MetS, particularly hyperglycemia and obesity, may increase the risk of esophageal adenocarcinoma. MetS, by and large, may not influence the risk of esophageal squamous cell carcinoma.

Circulating Inflammation Biomarkers and the Risk of Esophageal Adenocarcinoma: A Nested Case-Control Study in the Department of Defense Serum Repository

BACKGROUND

We previously identified associations of esophageal adenocarcinoma risk with four inflammation-related candidate biomarkers: TNF receptor 2 (TNFR2), IL17A, VEGFR3, and resistin.

METHODS

We aimed to replicate these candidates and discover novel associations with additional proteins. We conducted a nested case-control study of men with prediagnostic biospecimens stored at the US Department of Defense Serum Repository, including 203 incident esophageal adenocarcinoma cases. Controls were matched to cases in a ∼2:1 ratio by date of birth, race, service branch, and blood draw date. Multiplex immunoassays (Olink/Proseek panels) measured 254 proteins detected in ≥10% of all samples. Multivariable-adjusted conditional logistic regression models calculated associations between biomarker quantiles and esophageal adenocarcinoma. P values (<0.05) were used to indicate the statistical significance of candidates, and FDR was applied to the additional proteins. ORs from the current analysis and those from previous studies were combined for the candidate markers using fixed-effects meta-analysis.

RESULTS

Among the four candidates, the highest category of TNFR2 was associated with significantly increased esophageal adenocarcinoma risk (ORQ4 vs. Q1 = 1.87; 95% confidence interval: 1.02-3.42). In the meta-analysis, associations with esophageal adenocarcinoma were positive for TNFR2 (meta-analyzed ORhighest-vs.-lowest = 2.04; 1.12-2.95) and inverse for IL17A (meta-analyzed ORhighest-vs.-lowest = 0.53; 0.26-0.80). Of the additional 250 proteins, 45 were associated with esophageal adenocarcinoma risk and 6 (monocyte chemotactic protein 3, IL6, TNFR1, hepatocyte growth factor, TFF3, and FURIN) remained significant after FDR correction.

CONCLUSIONS

We confirmed associations of TNFR2 and IL17A with esophageal adenocarcinoma risk. Additionally, our study expands the range of proteins associated with esophageal adenocarcinoma development.

IMPACT

This is the largest assessment to discover novel associations of inflammation-related proteins with esophageal adenocarcinoma to date.

The Association Between Obesity and Malignant Progression of Barrett's Esophagus: A Systematic Review and Dose-Response Meta-Analysis

BACKGROUND AND AIMS

Obesity is a risk factor for both Barrett's esophagus (BE) and esophageal adenocarcinoma (EAC). However, it is unclear whether obesity drives the malignant progression of BE. We aimed to assess whether obesity is associated with high-grade dysplasia (HGD) or cancer in patients with BE.

METHODS

We searched MEDLINE and EMBASE from inception through April 2024 for studies reporting the effect of body mass index (BMI) on the progression of nondysplastic BE or low-grade dysplasia (LGD) to HGD or EAC. A 2-stage dose-response meta-analysis was performed to estimate the dose-response relationship between BMI with malignant progression. Study quality was appraised using a modified Newcastle-Ottawa scale.

RESULTS

Twenty studies reported data on 38,565 patients (74.4% male) in total, of whom 1684 patients were diagnosed with HGD/cancer. Nineteen studies were considered moderate to high quality. Eight cohort studies reported data on 6647 male patients with baseline nondysplastic BE/LGD, of whom 555 progressed to HGD/EAC (pooled annual rate of progression, 0.02%; 95% confidence interval [CI], 0.01%-0.03%), and 1992 female patients with baseline nondysplastic BE/LGD, with 110 progressors (pooled annual rate of progression, 0.01%; 95% CI, 0.01%-0.02%). There was no significant difference in pooled annual rate of progression between males and females (P = .15). Each 5-kg/m2 increase in BMI was associated with a 6% increase in the risk of malignant progression (adjusted odds ratio, 1.06; 95% CI, 1.02-1.10; P < .001; I2= 0%).

CONCLUSION

Our meta-analysis provides some evidence that obesity as measured by BMI is associated with malignant progression of BE with a dose-response relationship. This finding requires confirmation in future high-quality cohort studies. Future risk prediction models could incorporate measures of obesity to potentially improve risk stratification in patients with BE. PROSPERO, Number: CRD42017051046.

Gastroesophageal Cancer After Laparoscopic Sleeve Gastrectomy

Obesity has been linked to many types of cancers, and this association has received much attention. Here, we are reporting the case of a 41-year-old male patient, the second case diagnosed in our hospital with advanced metastatic gastroesophageal cancer eight years after laparoscopic sleeve gastrectomy. Routine preoperative endoscopy for all patients planned for bariatric surgery can play an important role in preoperative surgery selection, detection of abnormal pathology/lesions, as well as in postoperative follow-up/esophagogastroduodenoscopy surveillance plans, especially for patients identified as high-risk to develop cancer.

Translating Molecular Biology Discoveries to Develop Targeted Cancer Interception in Barrett's Esophagus

Esophageal adenocarcinoma (EAC) is a rapidly increasing lethal tumor. It commonly arises from a metaplastic segment known as Barrett's esophagus (BE), which delineates the at-risk population. Ample research has elucidated the pathogenesis of BE and its progression from metaplasia to invasive carcinoma; and multiple molecular pathways have been implicated in this process, presenting several points of cancer interception. Here, we explore the mechanisms of action of various agents, including proton pump inhibitors, non-steroidal anti-inflammatory drugs, metformin, and statins, and explain their roles in cancer interception. Data from the recent AspECT trial are discussed to determine how viable a multipronged approach to cancer chemoprevention would be. Further, novel concepts, such as the repurposing of chemotherapeutic drugs like dasatinib and the prevention of post-ablation BE recurrence using itraconazole, are discussed.

Global incidence, mortality, and burden of esophageal cancer, and its correlation with SDI, metabolic risks, fasting plasma glucose, LDL cholesterol, and body mass index: An ecological study

BACKGROUND AND AIMS

Esophageal cancer (EC) is one of the most common gastrointestinal malignancies. The geographical variation shows the influence of genetic factors, ethnicity, and distribution of various risk factors. Accurate knowledge of EC epidemiology at the global level will help to develop management strategies. Therefore, the present study was conducted to investigate the global and regional disease burden of EC, including the incidence, mortality, and burden of this cancer in 2019.

METHODS

Incidence, mortality, disability-adjusted life years (DALYs), and age-standardized rates (ASRs) associated with EC in 204 countries in different classifications were extracted from the global burden of disease study. After collecting information on metabolic risks, fasting plasma glucose (FPG), low-density lipoprotein (LDL) cholesterol, and body mass index (body mass index), the relationship between age-standardized incidence rate (ASIR), mortality rate, and DALYs with these variables was determined.

RESULTS

In 2019, 534,563 new cases of EC were reported worldwide. The highest ASIR is related to regions with medium sociodemographic index (SDI), and high middle income according to the World Bank, the Asian continent, and the western Pacific region. In 2019, a total of 498,067 deaths from EC were recorded. The highest mortality rate due to ASR is in countries with medium SDI and countries with upper middle income of the World Bank. In 2019, 1,166,017 DALYs were reported due to EC. The ASIR, ASDR, and DALYS ASR of EC showed a significant negative linear correlation with SDI, metabolic risks, high FPG, high LDL cholesterol, and high BMI (p < 0.05).

CONCLUSIONS

The results of this study showed significant gender and geographic variation in the incidence, mortality, and burden of EC. It is recommended to design and implement preventive approaches based on known risk factors and improve quality and access to efficient and appropriate treatments.

Dietary and Nutritional Support in Gastrointestinal Diseases of the Upper Gastrointestinal Tract (I): Esophagus

The esophagus is the centerpiece of the digestive system of individuals and plays an essential role in transporting swallowed nutrients to the stomach. Diseases of the esophagus can alter this mechanism either by causing anatomical damage that obstructs the lumen of the organ (e.g., peptic, or eosinophilic stricture) or by generating severe motility disorders that impair the progression of the alimentary bolus (e.g., severe dysphagia of neurological origin or achalasia). In all cases, nutrient assimilation may be compromised. In some cases (e.g., ingestion of corrosive agents), a hypercatabolic state is generated, which increases resting energy expenditure. This manuscript reviews current clinical guidelines on the dietary and nutritional management of esophageal disorders such as severe oropharyngeal dysphagia, achalasia, eosinophilic esophagitis, lesions by caustics, and gastroesophageal reflux disease and its complications (Barrett's esophagus and adenocarcinoma). The importance of nutritional support in improving outcomes is also highlighted.

Practical Considerations in Diagnosing and Managing Early-Onset GI Cancers

The incidence of early-onset (EO) GI cancers occurring in individuals younger than age 50 years has been rising at an alarming rate over the past two decades. Although this rise in incidence among young patients correlates with increased rates of obesity, changes in diet, and alterations in the environment, the effects of these environmental factors on carcinogenesis, metastasis, and treatment response are unknown. Although several unique clinical trends exist among EO-GI cancers and their average-onset GI cancer counterparts, GI cancers are molecularly indistinct between younger and older patients, and no data support distinct treatment paradigms for patients with EO disease. The majority of EO-GI cancers are not explained by germline changes. There remains a critical need for further research to understand the pathogenesis and optimal management of EO-GI cancers. In addition, current screening strategies are not adequate to identify EO-GI cancers, and early biomarkers are needed. Specialized centers, with a focus on psychosocial aspects of cancer management, can address the unique care needs of patients with EO-GI cancers.

Esophageal adenocarcinoma phenotypes and risk factors

PURPOSE OF REVIEW

The incidence of esophageal adenocarcinoma (EAC) has increased significantly over the last several decades. The majority of EAC patients present without a prior history of Barrett's esophagus (BE). As a result, endoscopic surveillance has made a suboptimal impact on EAC survival. These concerns raise serious question whether the time has come to take a different direction. The aim of this article is to review evolving evidence of EAC phenotypes and risk factors.

RECENT FINDINGS

A recent study has identified two phenotypes of EAC based on the presence or absence of intestinal metaplasia (IM) in the background of the tumor (BE/IM and non-BE/IM). The study found that one-half of patients with EAC have the non-BE/IM phenotype, which is associated with more aggressive behavior and worse survival. A retrospective review demonstrates that the proportion of the two phenotypes has been stable over the last decades. Similarly, the increasing incidence of EAC cannot be explained by an increased frequency of new, unique risk factors but rather by a higher prevalence of already known risk factors. Emerging data also demonstrates that, whereas reflux symptoms are an unreliable feature for screening regardless of phenotype, the absence of reflux symptoms is more common for the non-BE/IM. Differences in the degree of genomic methylation and immune response might explain the two phenotypes at a genomic level.

SUMMARY

EAC phenotypes have implications for tumor behavior and phenotypic differences might underlie our suboptimal screening efforts. Future screening efforts should not uniformly rely on reflux symptoms as a prerequisite for screening and should consider alternatives to the current screening strategy.

Role of Obesity, Physical Exercise, Adipose Tissue-Skeletal Muscle Crosstalk and Molecular Advances in Barrett's Esophagus and Esophageal Adenocarcinoma

Both obesity and esophageal adenocarcinoma (EAC) rates have increased sharply in the United States and Western Europe in recent years. EAC is a classic example of obesity-related cancer where the risk of EAC increases with increasing body mass index. Pathologically altered visceral fat in obesity appears to play a key role in this process. Visceral obesity may promote EAC by directly affecting gastroesophageal reflux disease and Barrett’s esophagus (BE), as well as a less reflux-dependent effect, including the release of pro-inflammatory adipokines and insulin resistance. Deregulation of adipokine production, such as the shift to an increased amount of leptin relative to “protective” adiponectin, has been implicated in the pathogenesis of BE and EAC. This review discusses not only the epidemiology and pathophysiology of obesity in BE and EAC, but also molecular alterations at the level of mRNA and proteins associated with these esophageal pathologies and the potential role of adipokines and myokines in these disorders. Particular attention is given to discussing the possible crosstalk of adipokines and myokines during exercise. It is concluded that lifestyle interventions to increase regular physical activity could be helpful as a promising strategy for preventing the development of BE and EAC.

Insulin and cancer: a tangled web

For a century, since the pioneering work of Otto Warburg, the interwoven relationship between metabolism and cancer has been appreciated. More recently, with obesity rates rising in the U.S. and worldwide, epidemiologic evidence has supported a link between obesity and cancer. A substantial body of work seeks to mechanistically unpack the association between obesity, altered metabolism, and cancer. Without question, these relationships are multifactorial and cannot be distilled to a single obesity- and metabolism-altering hormone, substrate, or factor. However, it is important to understand the hormone-specific associations between metabolism and cancer. Here, we review the links between obesity, metabolic dysregulation, insulin, and cancer, with an emphasis on current investigational metabolic adjuncts to standard-of-care cancer treatment.

Burden of esophageal cancer and its attributable risk factors in 204 countries and territories from 1990 to 2019

BACKGROUND

Esophageal cancer is a global health concern. Regularly updated data about the burden of esophageal cancer are essential for formulating specific public policies. We aimed to estimate the global, regional, and national burden and trends of esophageal cancer and its attributable risk factors from 1990 to 2019, by age, sex and socio-demographic index (SDI).

METHODS

Data about the incidence, death, disability-adjusted life-years (DALYs), and age-standardized rates were collected from Global Burden of Disease study 2019. Estimated annual percentage changes were used to quantify the temporal trends of age-standardized rates. Moreover, the risk factors attributable to esophageal cancer deaths were also presented.

RESULTS

There were 534,563 incident cases and 498,067 deaths in 2019, contributing to 11,666,017 DALYs. The absolute numbers of incidence, death, and DALYs had increased from 1990 to 2019, contrasting with declined changes in their corresponding age-standardized rates. The burden of esophageal cancer varied across different regions and countries, and the age-standardized rates were negative with SDI. Almost half of the esophageal cancer was concentrated in China. Males accounted for most of the burden of esophageal cancer, and the onset age tended to be older. The death of esophageal cancer was primarily attributable to smoking, followed by alcohol use, high body mass index, diet low in fruits and diet low in vegetables.

CONCLUSION

The burden of esophageal cancer was heterogeneous across regions and countries by sex, age, and SDI, providing information for governments that may help to formulate more targeted policies.

The tumour immune microenvironment in oesophageal cancer

Oesophageal cancer (OC) is an inflammation-associated malignancy linked to gastro-oesophageal reflux disease, obesity and tobacco use. Knowledge of the microenvironment of oesophageal tumours is relevant to our understanding of the development of OC and its biology, and has major implications for understanding the response to standard therapies and immunotherapies, as well as for uncovering novel targets. In this context, we discuss what is known about the TME in OC from tumour initiation to development and progression, and how this is relevant to therapy sensitivity and resistance in the two major types of OC. We provide an immunological characterisation of the OC TME and discuss its prognostic implications with specific comparison with the Immunoscore and immune-hot, -cold, altered-immunosuppressed and -altered-excluded models. Targeted therapeutics for the TME under pre-clinical and clinical investigation in OCs are also summarised. A deeper understanding of the TME will enable the development of combination approaches to concurrently target the tumour cells and TME delivering precision medicine to OC patients.

Leptin activates Akt in oesophageal cancer cells via multiple atorvastatin-sensitive small GTPases

Obesity is a risk factor for Barrett's oesophagus and oesophageal adenocarcinoma. Adipose tissue secretes the hormone leptin. Leptin is a growth factor for several cell types, including Barrett's cells and oesophageal adenocarcinoma cells. Statins are associated with reduced rates of Barrett's oesophagus and oesophageal cancer and exhibit anti-cancer effects in vitro. The mechanisms of these effects are not fully established. We have examined the effects of leptin and the lipid-soluble statin, atorvastatin, on signalling via monomeric GTP-binding proteins and Akt. Proliferation and apoptosis were assessed in OE33 cells. Akt activity was quantified by cell-based ELISA and in vitro kinase assay. Specific small-molecule inhibitors and a dominant-negative construct were used to reduce Akt activity. Small GTPases were inhibited using transfection of dominant-negative plasmids, prenylation inhibitors and pretreatment with atorvastatin. Leptin stimulated Akt activity and cell proliferation and inhibited camptothecin-induced apoptosis in an Akt-sensitive manner. Leptin induced phosphorylation of Bad and FOXO1 in an Akt-sensitive manner. Leptin activated Ras, Rac, RhoA and cdc42. Transfection of dominant-negative plasmids confirmed that leptin-induced Akt activation required Ras, RhoA cdc42 but not Rac. Atorvastatin inhibited leptin-induced activation of Ras, RhoA, cdc42 and Akt. Co-treatment with mevalonate prevented these effects of atorvastatin. The protein kinase Akt is essential to the growth-promoting and anti-apoptotic effects of leptin in oesophageal adenocarcinoma cells. Akt is activated via Ras-, Rho- and cdc42-dependant pathways. Atorvastatin reduces leptin-induced Akt activation by inhibiting prenylation of small GTPases. This may explain the reduced incidence of oesophageal adenocarcinoma in statin-users.

Challenges and perspectives for immunotherapy in oesophageal cancer: A look to the future (Review)

Oesophageal cancer is one of the most aggressive malignancies with limited treatment options, thus resulting in a high morbidity and mortality. With 5‑year survival rates of only 5‑10%, oesophageal cancer holds a dismal prognosis for patients. In order to improve overall survival, the early diagnosis and tools for patient stratification for personalized treatment are urgent needs. A minority of oesophageal cancers belong to the spectrum of Lynch syndrome‑associated cancers and are characterized by microsatellite instability (MSI). Microsatellite instability is a consequence of defective mismatch repair protein functions and it has been well characterized in other gastrointestinal tumours, such as colorectal and gastric cancer. In the latter, high levels of MSI are associated with a better prognosis and with an increased benefit to immune‑based therapies. Therefore, similar therapeutic approaches could offer an opportunity of treatment for oesophageal cancer patients with MSI. Apart from immune checkpoint inhibitors, other immunotherapies such as adoptive T‑cell transfer, peptide vaccine and oncolytic viruses are under investigation in oesophageal cancer patients. In the present review, the rationale and current knowledge about immunotherapies in oesophageal cancer are summarised.

Lifestyle Risk Factors, Quality of Life, and Intervention Preferences of Barrett's Esophagus Patients: A Prospective Cohort Study

BACKGROUND AND AIMS

Lifestyle counseling to achieve a healthy weight, quit smoking, and reduce alcohol is a cornerstone in the management of Barrett's Esophagus (BE). However, little is known about whether patients make these recommended lifestyle changes or the impact of non-adherence on their quality of life (QOL). This study characterized the lifestyle risk factors, QOL, and intervention preferences of BE patients as a first step toward developing lifestyle change interventions for this population.

METHODS

Patients with a confirmed BE diagnosis (N = 106) completed surveys at a surveillance endoscopy visit (baseline) and at 3- and 6-month follow-ups. Patients reported on lifestyle risk factors, adherence determinants (e.g., perceived benefits/barriers, risk, intentions), QOL, and intervention preferences.

RESULTS

Most patients (56%) had uncontrolled reflux, were overweight/obese (65.1%), and had low dietary fiber intake (91%). Many (45%) reported poor QOL. Patients' perceived risk of developing esophageal cancer was high, but their behavior change intentions were low. Despite receiving lifestyle counseling from physicians, there were no significant changes in patients' QOL or lifestyle risk factors over time. Nonetheless, patients indicated strong interest in internet (62.6%) and multimedia programs (57.9%) addressing acid reflux and weight control.

CONCLUSION

BE patients reported uncontrolled reflux, poor QOL, and multiple lifestyle risk factors that did not change over time. Despite low levels of intention for making lifestyle changes, patients were interested receiving more information about controlling acid reflux, suggesting a potential teachable moment and opportunity for web-based and multimedia multiple behavior interventions that seek to control acid reflux symptoms through weight loss and a high fiber diet.

Crossroad between Obesity and Gastrointestinal Cancers: A Review of Molecular Mechanisms and Interventions

The burden of gastrointestinal (GI) cancer is increasing worldwide, and in the past decade, cancer had entered the list of chronic debilitating diseases whose risk is substantially increased by hypernutrition. Obesity may increase the risk of cancer by the imbalance of various mechanisms including insulin and insulin-like growth factor1 (IGF-I) signaling, systemic inflammation, immune dysregulation, tumor angiogenesis, adipokines secretion, and intestinal microbiota that usually act interdependently. An increased understanding of the mechanisms underlying obesity-GI cancer link can provide multiple opportunities for cancer prevention. This review discusses various mechanisms involved molecular mechanisms linking obesity with GI cancers including esophagus, stomach, colorectal and hepatocellular. Furthermore, an optional intervention such as diet restriction and exercise is described, which may be preventive or therapeutic in GI cancer.

Metabolic syndrome and esophageal cancer risk: a systematic review and meta‑analysis

OBJECTIVE

Many clinical studies evaluating the relationship between metabolic syndrome and esophageal cancer yielded uncertain results. The purpose of this study is to systematically assess the relationship between metabolic syndrome and esophageal cancer.

METHODS

We searched clinical studies on metabolic syndrome and esophageal cancer risk in PubMed, Embase, and the Cochrane Library. Meta-analysis was conducted by RevMan 5.3 softwares.

RESULTS

A total of four cohort studies and two case-control studies met eligibility criteria and were included in the meta-analysis. Meta-analysis using a fixed-effect model indicated that MetS was related with a higher risk of EC (OR: 1.16, 95% CI 1.08-1.25). Subgroup analyses grouped by pathological types showed that MetS was related with a higher risk of EAC (OR: 1.19, 95% CI 1.10-1.28). Subgroup analyses grouped by metabolic conditions showed hyperglycemia (OR: 1.12, 95% CI 1.03-1.21),hypertension (OR: 1.23, 95% CI 1.04-1.46), obesity (OR: 1.40, 95% CI 1.22-1.60, P < 0.05) were related with a higher risk of EAC.

CONCLUSIONS

Overall, our meta-analysis provides high quality evidence that metabolic syndrome was related with a higher risk of EAC. Among the individual components of the metabolic syndrome, hyperglycemia, hypertension and obesity may be the key factors.

Risk Factor Profiles Can Distinguish Esophageal Adenocarcinoma From Barrett's Esophagus

INTRODUCTION

It is assumed that screening risk factors for Barrett's esophagus (BE) and prevalent esophageal adenocarcinoma (EAC) are the same.

METHODS

A matched case-control study comparing risk factors between EAC and BE was performed.

RESULTS

In 1,356 patients (678 with EAC and 678 with BE), heartburn (52.7%), diabetes, hyperlipidemia, hypertension, nonalcoholic steatohepatitis, and metabolic syndrome were less common in EAC (52.7, 29.2, 45.7, 48.2, 12, and 28.5%, resp.) compared with BE (84.5, 37.6, 82.2, 64.6, 18.4, and 44.1%, P < 0.01). Mean alanine aminotransferase and HgA1c levels were also significantly lower in EAC compared with BE.

DISCUSSION

Optimal strategies for screening for prevalent EAC may be different than that for BE.

Roles of Adipokines in Digestive Diseases: Markers of Inflammation, Metabolic Alteration and Disease Progression

Adipose tissue is a highly dynamic endocrine tissue and constitutes a central node in the interorgan crosstalk network through adipokines, which cause pleiotropic effects, including the modulation of angiogenesis, metabolism, and inflammation. Specifically, digestive cancers grow anatomically near adipose tissue. During their interaction with cancer cells, adipocytes are reprogrammed into cancer-associated adipocytes and secrete adipokines to affect tumor cells. Moreover, the liver is the central metabolic hub. Adipose tissue and the liver cooperatively regulate whole-body energy homeostasis via adipokines. Obesity, the excessive accumulation of adipose tissue due to hyperplasia and hypertrophy, is currently considered a global epidemic and is related to low-grade systemic inflammation characterized by altered adipokine regulation. Obesity-related digestive diseases, including gastroesophageal reflux disease, Barrett's esophagus, esophageal cancer, colon polyps and cancer, non-alcoholic fatty liver disease, viral hepatitis-related diseases, cholelithiasis, gallbladder cancer, cholangiocarcinoma, pancreatic cancer, and diabetes, might cause specific alterations in adipokine profiles. These patterns and associated bases potentially contribute to the identification of prognostic biomarkers and therapeutic approaches for the associated digestive diseases. This review highlights important findings about altered adipokine profiles relevant to digestive diseases, including hepatic, pancreatic, gastrointestinal, and biliary tract diseases, with a perspective on clinical implications and mechanistic explorations.

Circulating Levels of Inflammatory and Metabolic Biomarkers and Risk of Esophageal Adenocarcinoma and Barrett Esophagus: Systematic Review and Meta-analysis

Associations between circulating levels of obesity-related biomarkers and risk of esophageal adenocarcinoma and Barrett esophagus have been reported, but the results are inconsistent. A literature search until October 2018 in MEDLINE and EMBASE was performed. Pooled ORs with 95% confidence intervals (CI) were estimated for associations between 13 obesity-related inflammatory and metabolic biomarkers and risk of esophageal adenocarcinoma or Barrett esophagus using random effect meta-analyses. Among 7,641 studies, 19 were eligible for inclusion (12 cross-sectional, two nested case-control, and five cohort studies). Comparing the highest versus lowest categories of circulating biomarker levels, the pooled ORs were increased for leptin (OR, 1.68; 95% CI, 0.95-2.97 for Barrett esophagus), glucose (OR, 1.12; 95% CI, 1.03-1.22 for esophageal adenocarcinoma), insulin (OR, 1.47; 95% CI, 1.06-2.00 for Barrett esophagus), C-reactive protein (CRP; OR, 2.06; 95% CI, 1.28-3.31 for esophageal adenocarcinoma), IL6 (OR, 1.50; 95% CI, 1.03-2.19 for esophageal adenocarcinoma), and soluble TNF receptor 2 (sTNFR-2; OR, 3.16; 95% CI, 1.76-5.65 for esophageal adenocarcinoma). No associations were identified for adiponectin, ghrelin, insulin-like growth factor 1, insulin-like growth factor-binding protein 3, triglycerides, IL8, or TNFα. Higher circulating levels of leptin, glucose, insulin, CRP, IL6, and sTNFR-2 may be associated with an increased risk of esophageal adenocarcinoma or Barrett esophagus. More prospective studies are required to identify biomarkers that can help select high-risk individuals for targeted prevention and early detection.

The Evolving Landscape of Esophageal Cancer: A Four-Decade Analysis

The incidence of esophageal cancer in the United States seems to have significantly increased since the 1970s. In undertaking this study, we sought to describe changes in the incidence, histologic type, and presenting stage of esophageal cancer over the past four decades. With Institutional Review Board approval, the Surveillance, Epidemiology, and End Results database of the National Cancer Institute was queried. Regression analysis was used to analyze data, and significance was accepted with 95 per cent probability. Forty-two thousand seven hundred thirty-nine patients had squamous cell carcinoma or adenocarcinoma located in their upper, middle, and/ or lower esophagus from 1973 through 2010, reflecting a 7.5-fold annual increase from 1973 through 2010. Squamous cell carcinoma increased annually 2.5-fold ( P < 0.001) and esophageal adenocarcinoma increased annually 57-fold from 1973 through 2010 ( P < 0.001), whereas the overall population in the United States increased only 43 per cent (215,092,900 to 308,745,538) in the same period. From 1973 through 2010, there was a significant increase in the incidence of esophageal cancer in the United States. This increase was much greater than the increase in the population in the United States. The incidence of adenocarcinoma increased much more than that of squamous cell carcinoma of the esophagus from 1973 through 2010.

Obesity and esophageal cancer: GERD, Barrett´s esophagus, and molecular carcinogenic pathways

INTRODUCTION

Increases in the rates of esophageal adenocarcinoma (EAC) have paralleled rises in the prevalence of overweight and obesity. Despite not being fully understood, obesity-related EAC seems to have different carcinogenic pathways.

AREAS COVERED

This comprehensive review will thoroughly evaluate the current literature, describing the underlying mechanisms that help understanding the strong association between obesity and esophageal cancer.

EXPERT COMMENTARY

The risk of esophageal cancer among obese individuals could be partially explained by several factors: high prevalence of GERD; linear association between central adiposity and Barrett´s esophagus development; low levels of adiponectin and high levels of leptin that alter cell proliferation processes; insulin-resistant state that creates a tumorigenesis environment; and changes in the esophageal microbiota due to unhealthy dietary habits that promote carcinogenesis. In addition, a large proportion of obese patients are undergoing sleeve gastrectomy which can worsen GERD or cause de novo reflux, esophagitis, and Barrett´s metaplasia.

The relationship between metabolic syndrome and increased risk of Barrett's esophagus: an updated systematic review and meta-analysis

BACKGROUND

The relationship between metabolic syndrome (MetS) and Barrett's esophagus (BE) is still a challenging issue, and inconsistent results have been reported in different studies. Therefore, this study was conducted to determine the relationship between MetS and BE.

METHODS

In this study, we followed the MOOSE protocol and results were reported according to the PRISMA guidelines. All study steps were performed independently by two authors. If necessary, the dispute was resolved by consultation with a third author. The search strategy is designed to find published studies. Comprehensive search was done in the following databases until July 2019: Cochrane Library, PubMed/Medline, Web of Science, Science Direct, EMBASE, Scopus, CINAHL, EBSCO, and Google Scholar search engine. All analyses were performed using Comprehensive Meta-Analysis Software Ver.2, while p-value lower than 0.05 was considered significant.

RESULTS

In 14 studies with a sample size of 108,416, MetS significantly increased the risk of BE (OR = 1.354; 95% CI: 1.145-1.600; P < 0.001; Heterogeneity: I2 = 81.95%; P < 0.001). Sensitivity analysis by omitting one study showed that overall estimates are still robust. Subgroup analysis was significant for continent (P < 0.001) and MetS diagnostic criteria (P = 0.043), but was not significant for variables of study type (P = 0.899), study setting (P = 0.115), control groups (P = 0.671) and quality of studies (P = 0.603). The Begg (P = 0.912) and Egger's (P = 0.094) tests were not significant; therefore, the publication bias did not play a role in the results.

CONCLUSION

MetS increases the risk of BE compared to control groups. The results of this study can help health practitioners by identifying a treatable risk factor for the most important risk factor for esophageal carcinoma (ie, BE). Future studies should examine whether treatment for MetS reduces the risk of BE.

Bariatric surgery and gastroesophageal reflux disease

With the rapidly increasing prevalence of obesity globally, the practice of bariatric surgery is being adopted routinely to prevent the development of chronic conditions as well as some forms of cancers associated with obesity. Gastroesophageal reflux disease (GERD) is one of those chronic conditions. Furthermore, there is accumulating data that obesity is associated with complications related to longstanding GERD such as erosive esophagitis (EE), Barrett's esophagus (BE), and esophageal adenocarcinoma (EAC). Central obesity, rather than body mass index (BMI), appears to be more closely associated with these complications. It should be expected, therefore, that weight loss procedures should result in improvement in GERD symptoms and its associated complications. However, in reality the different bariatric surgical procedures have unpredictable effects on an established GERD and may even produce GERD symptoms for the very first time (de novo). In this review, we explore the literature studying the effects of bariatric surgical operations on GERD. Roux-en-Y gastric bypass appears to have the most beneficial effect on GERD. On the other hand, laparoscopic sleeve gastrectomy and laparoscopic adjustable gastric banding (LAGB) are linked with long-term increased prevalence of GERD. We argue that GERD is an extremely important preoperative consideration for any patient undergoing bariatric surgery and therefore should be thoroughly investigated objectively (with 24-hour pH study and high-resolution manometry) to select the most suitable bariatric procedure for patients for their long-term success.

Incidence of Dysplasia in Obese vs Nonobese Patients With Nondysplastic Barrett Esophagus

Background: Obesity is a known independent risk factor for both Barrett esophagus and esophageal adenocarcinoma. However, data about the effect of obesity on the risk of progression from nondysplastic Barrett esophagus to dysplasia or esophageal adenocarcinoma are lacking. The aim of this study was to evaluate whether obese patients with nondysplastic Barrett esophagus had a higher incidence of dysplasia development during routine surveillance than nonobese patients. Methods: In a retrospective review, 1,999 patients who had a first diagnosis of nondysplastic Barrett esophagus made by esophagogastroduodenoscopy (EGD) at a single community hospital were tracked to their surveillance EGD 3 to 5 years later to evaluate for dysplasia (low grade, high grade, or adenocarcinoma). We compared the incidence of dysplasia development in obese patients (body mass index [BMI] ≥30 kg/m²) with nonobese patients (BMI <30 kg/m²). Results: The sample population included 1,019 obese patients (51.0%) and 980 nonobese patients (49.0%) with nondysplastic Barrett esophagus. Their mean age was 56.5 ± 11.6 years, 1,228 (61.4%) were male, and 1,853 (92.7%) were Caucasian. At surveillance endoscopy performed at a mean follow-up of 3.7 years after their first EGD, 51 obese patients (incidence of 15.3 cases per 1,000 person-years, 95% confidence interval [CI], 11.5-19.9) and 15 nonobese patients (incidence of 4.6 cases per 1,000 person-years, 95% CI, 2.7-7.4) had developed dysplasia (P=0.0001). Conclusion: We found a significant increase in the incidence of dysplasia development in obese patients with nondysplastic Barrett esophagus at 3- to 5-year follow-up compared to nonobese patients. This finding suggests that more frequent surveillance in obese patients with nondysplastic Barrett esophagus may be warranted for early detection of dysplasia.

High-Fat Diet Accelerates Carcinogenesis in a Mouse Model of Barrett's Esophagus via Interleukin 8 and Alterations to the Gut Microbiome

BACKGROUND & AIMS

Barrett's esophagus (BE) is a precursor to esophageal adenocarcinoma (EAC). Progression from BE to cancer is associated with obesity, possibly due to increased abdominal pressure and gastroesophageal reflux disease, although this pathogenic mechanism has not been proven. We investigated whether environmental or dietary factors associated with obesity contribute to the progression of BE to EAC in mice.

METHODS

Tg(ED-L2-IL1RN/IL1B)#Tcw mice (a model of BE, called L2-IL1B mice) were fed a chow (control) or high-fat diet (HFD) or were crossbred with mice that express human interleukin (IL) 8 (L2-IL1B/IL8 mice). Esophageal tissues were collected and analyzed for gene expression profiles and by quantitative polymerase chain reaction, immunohistochemistry, and flow cytometry. Organoids were established from BE tissue of mice and cultured with serum from lean or obese individuals or with neutrophils from L2-IL1B mice. Feces from mice were analyzed by 16s ribosomal RNA sequencing and compared to 16s sequencing data from patients with dysplasia or BE. L2-IL1B were mice raised in germ-free conditions.

RESULTS

L2-IL1B mice fed an HFD developed esophageal dysplasia and tumors more rapidly than mice fed the control diet; the speed of tumor development was independent of body weight. The acceleration of dysplasia by the HFD in the L2-IL1B mice was associated with a shift in the gut microbiota and an increased ratio of neutrophils to natural killer cells in esophageal tissues compared with mice fed a control diet. We observed similar differences in the microbiomes from patients with BE that progressed to EAC vs patients with BE that did not develop into cancer. Tissues from dysplasias of L2-IL1B mice fed the HFD contained increased levels of cytokines that are produced in response to CXCL1 (the functional mouse homolog of IL8, also called KC). Serum from obese patients caused organoids from L2-IL1B/IL8 mice to produce IL8. BE tissues from L2-IL1B mice fed the HFD and from L2-IL1B/IL8 mice contained increased numbers of myeloid cells and cells expressing Cxcr2 and Lgr5 messenger RNAs (epithelial progenitors) compared with mice fed control diets. BE tissues from L2-IL1B mice raised in germ-free housing had fewer progenitor cells and developed less dysplasia than in L2-IL1 mice raised under standard conditions; exposure of fecal microbiota from L2-IL1B mice fed the HFD to L2-IL1B mice fed the control diet accelerated tumor development.

CONCLUSIONS

In a mouse model of BE, we found that an HFD promoted dysplasia by altering the esophageal microenvironment and gut microbiome, thereby inducing inflammation and stem cell expansion, independent of obesity.

Prediagnostic circulating markers of inflammation and risk of oesophageal adenocarcinoma: a study within the National Cancer Institute Cohort Consortium

OBJECTIVE

Cross-sectional data indicate that systemic inflammation is important in oesophageal adenocarcinoma. We conducted a prospective study to assess whether prediagnostic circulating markers of inflammation were associated with oesophageal adenocarcinoma and to what extent they mediated associations of obesity and cigarette smoking with cancer risk.

DESIGN

This nested case-control study included 296 oesophageal adenocarcinoma cases and 296 incidence density matched controls from seven prospective cohort studies. We quantitated 69 circulating inflammation markers using Luminex-based multiplex assays. Conditional logistic regression models estimated associations between inflammation markers and oesophageal adenocarcinoma, as well as direct and indirect effects of obesity and smoking on risk of malignancy.

RESULTS

Soluble tumour necrosis factor receptor 2 (sTNFR2) (ORsquartile 4 vs 1=2.67, 95% CI 1.52 to 4.68) was significantly associated with oesophageal adenocarcinoma. Additional markers close to the adjusted significance threshold included C reactive protein, serum amyloid A, lipocalin-2, resistin, interleukin (IL) 3, IL17A, soluble IL-6 receptor and soluble vascular endothelial growth factor receptor 3. Adjustment for body mass index, waist circumference or smoking status slightly attenuated biomarker-cancer associations. Mediation analysis indicated that sTNFR2 may account for 33% (p=0.005) of the effect of waist circumference on oesophageal adenocarcinoma risk. Resistin, plasminogen activator inhibitor 1, C reactive protein and serum amyloid A were also identified as potential mediators of obesity-oesophageal adenocarcinoma associations. For smoking status, only plasminogen activator inhibitor 1 was a nominally statistically significant (p<0.05) mediator of cancer risk.

CONCLUSION

This prospective study provides evidence of a link between systemic inflammation and oesophageal adenocarcinoma risk. In addition, this study provides the first evidence that indirect effects of excess adiposity and cigarette smoking, via systemic inflammation, increase the risk of oesophageal adenocarcinoma.

Low-density lipoprotein promotes lymphatic metastasis of esophageal squamous cell carcinoma and is an adverse prognostic factor

The purpose of the current study was to investigate the prognostic role of preoperative serum lipid levels in patients with esophageal squamous cell carcinoma (ESCC) and to preliminarily explore the mechanism of serum lipids in this disease. Preoperative lipids, including total cholesterol, low-density lipoprotein (LDL) cholesterol, high-density lipoprotein (HDL) cholesterol and triglyceride levels, were assessed in 242 patients with ESCC. To eliminate the influence of nutritional status, all patients had previously undergone esophagectomy. Univariate and multivariate Cox regression analyses were performed to identify predictors of overall survival (OS). Associations between significant lipid targets and clinical features were then analyzed and the results were validated using TE-1 and ECa109 esophageal cancer cell lines. The cell proliferation was evaluated with a Cell Counting Kit-8 (CCK8) assay and the cell cycle was assessed with propidium iodide staining and flow cytometry. Univariate analysis revealed that HDL (P=0.048), LDL (P=0.020), Pathological T-staging status (pT status) (P=0.001), Pathological N-staging status (pN status) (P=0.001) and histological differentiation (P=0.002) were significantly associated with OS. Based on multivariate analysis, LDL [hazard ratio (HR)=2.164, P=0.005], pT status (HR=1.714, P=0.001), pN status (HR=1.966, P=0.001) and histological differentiation (HR=4.083, P=0.002) were risk factors in patients with ESCC. A high LDL level (>3.12 mmol/l) was associated with sex (P=0.001), tumor location (P=0.004) and a higher susceptibility to lymphatic metastasis (P=0.007). A CCK8 assay demonstrated that LDL promoted TE-1 and ECa109 cell proliferation, and flow cytometry analysis revealed that treatment with LDL at an appropriate concentration resulted in an accumulation of cells in G2 phase and decreased the number of cells in G1 phase. In summary, the current study identified that preoperative LDL serum level serves an important role in predicting ESCC outcome as LDL promotes lymphatic metastasis. Furthermore, a preliminary mechanism for this association has been validated in vitro.

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.

ESCC ATLAS: A population wide compendium of biomarkers for Esophageal Squamous Cell Carcinoma

Esophageal cancer (EC) is the eighth most aggressive malignancy and its treatment remains a challenge due to the lack of biomarkers that can facilitate early detection. EC is identified in two major histological forms namely - Adenocarcinoma (EAC) and Squamous cell carcinoma (ESCC), each showing differences in the incidence among populations that are geographically separated. Hence the detection of potential drug target and biomarkers demands a population-centric understanding of the molecular and cellular mechanisms of EC. To provide an adequate impetus to the biomarker discovery for ESCC, which is the most prevalent esophageal cancer worldwide, here we have developed ESCC ATLAS, a manually curated database that integrates genetic, epigenetic, transcriptomic, and proteomic ESCC-related genes from the published literature. It consists of 3475 genes associated to molecular signatures such as, altered transcription (2600), altered translation (560), contain copy number variation/structural variations (233), SNPs (102), altered DNA methylation (82), Histone modifications (16) and miRNA based regulation (261). We provide a user-friendly web interface ( http://www.esccatlas.org , freely accessible for academic, non-profit users) that facilitates the exploration and the analysis of genes among different populations. We anticipate it to be a valuable resource for the population specific investigation and biomarker discovery for ESCC.

ESCC ATLAS: A population wide compendium of biomarkers for Esophageal Squamous Cell Carcinoma

Esophageal cancer (EC) is the eighth most aggressive malignancy and its treatment remains a challenge due to the lack of biomarkers that can facilitate early detection. EC is identified in two major histological forms namely - Adenocarcinoma (EAC) and Squamous cell carcinoma (ESCC), each showing differences in the incidence among populations that are geographically separated. Hence the detection of potential drug target and biomarkers demands a population-centric understanding of the molecular and cellular mechanisms of EC. To provide an adequate impetus to the biomarker discovery for ESCC, which is the most prevalent esophageal cancer worldwide, here we have developed ESCC ATLAS, a manually curated database that integrates genetic, epigenetic, transcriptomic, and proteomic ESCC-related genes from the published literature. It consists of 3475 genes associated to molecular signatures such as, altered transcription (2600), altered translation (560), contain copy number variation/structural variations (233), SNPs (102), altered DNA methylation (82), Histone modifications (16) and miRNA based regulation (261). We provide a user-friendly web interface ( http://www.esccatlas.org , freely accessible for academic, non-profit users) that facilitates the exploration and the analysis of genes among different populations. We anticipate it to be a valuable resource for the population specific investigation and biomarker discovery for ESCC.

The Role of Adipokines in the Establishment and Progression of Head and Neck Neoplasms

Adipokines constitute a family of protein factors secreted by white adipose tissue (WAT), that regulate the functions of WAT and other sites. Leptin, adiponectin and resistin, are the main adipokines present in serum and saliva, targeting several tissues and organs, including vessels, muscles, liver and pancreas. Besides body mass regulation, adipokines affect glucose homeostasis, inflammation, angiogenesis, cell proliferation and apoptosis, and other crucial cell procedures. Their involvement in tumor formation and growth is well established and deregulation of adipokine and adipokine receptors' expression is observed in several malignancies including those located in the head and neck region. Intracellular effects of adipokines are mediated by a plethora of receptors that activate several signaling cascades including Janus kinase/ Signal transducer and activator of transcription (JAK/ STAT pathway), Phospatidylinositol kinase (PI3/ Akt/ mTOR) and Peroxisome proliferator-activated receptor (PPAR). The present review summarizes the current knowledge on the role of adipokines family members in carcinogenesis of the head and neck region. The diagnostic and prognostic significance of adipokines and their potential role as serum and saliva biomarkers are also discussed.

Obesity increases the risk of erosive esophagitis but metabolic unhealthiness alone does not: a large-scale cross-sectional study

BACKGROUND

Obesity is a known risk factor for erosive esophagitis (EE) and metabolic unhealthiness has been implicated in EE pathogenesis. However, obesity and metabolic unhealthiness are not synonymous and the associations between obesity, metabolic health, and EE are unclear. Therefore, our aim was to investigate the relationship between EE, obesity, and metabolic health.

METHODS

We performed a retrospective cross-sectional study of subjects undergoing health screening at a university hospital. Subjects were classified into 4 groups based on metabolic and obesity criteria: metabolically healthy nonobese (MHNO), metabolically healthy obese (MHO), metabolically unhealthy nonobese (MUNO), and metabolically unhealthy obese (MUO). Multivariable analysis was used to identify EE risk factors with MHNO subjects as reference. To determine if there were synergistic interactions between metabolic health and obesity status, the Rothman's synergy index and attributable proportion of risk were also calculated.

RESULTS

We included 10,338 subjects (5448 MHNO, 1605 MHO, 1600 MUNO, 1685 MUO). The prevalence of EE was 6.5% in MHNO, 12.6% in MHO, 9.3% in MUNO, and 14.3% in MUO. EE risk was increased significantly by obesity (MHO: OR, 1.589, 95% CI, 1.314-1.921, P < 0.001; MUO: OR, 1.734, 95% CI, 1.441-2.085, P < 0.001), but not in MUNO subjects (OR, 1.224, 95% CI, 0.991-1.511, P = 0.060). Male sex, blood leukocyte count, alcohol, and smoking significantly increased EE risk, but H. pylori infection was protective. Replacement of obesity with abdominal obesity gave similar results. The Rothman's synergy index was 0.920 (95% CI, 0.143-5.899) and the attributable proportion of risk was - 0.051 (95% CI, - 1.206-1.105), indicating no interaction between metabolic and obesity status on EE risk.

CONCLUSIONS

We demonstrated that obesity increased the risk of EE, regardless of metabolic health status. However, EE risk was not significantly increased in MUNO subjects, suggesting that metabolic unhealthiness may not be involved in EE pathogenesis. As observational cross-sectional studies cannot prove causality, prospective longitudinal studies involving obesity and metabolic treatment should be performed to further investigate the association between obesity, metabolic health, and EE risk.

Obesity-Related Digestive Diseases and Their Pathophysiology

Obesity is a growing medical and public health problem worldwide. Many digestive diseases are related to obesity. In this article, the current state of our knowledge of obesity-related digestive diseases, their pathogenesis, and the medical and metabolic consequences of weight reduction are discussed. Obesity-related digestive diseases include gastroesophageal reflux disease, Barrett’s esophagus, esophageal cancer, colon polyp and cancer, nonalcoholic fatty liver disease, hepatitis C-related disease, hepatocellular carcinoma, gallstone, cholangiocarcinoma, and pancreatic cancer. Although obesity-related esophageal diseases are associated with altered mechanical and humoral factors, other obesity-related digestive diseases seem to be associated with obesity-induced altered circulating levels of adipocytokines and insulin resistance. The relationship between functional gastrointestinal disease and obesity has been debated. This review provides a comprehensive evaluation of the obesity-related digestive diseases, including pathophysiology, obesity-related risk, and medical and metabolic effects of weight reduction in obese subjects.

Blood biomarkers for early diagnosis of oesophageal cancer: a systematic review

BACKGROUND

Oesophageal cancer prognosis remains poor owing to the inability to detect the disease at an early stage. Nontissue (serum, urinary or salivary) biomarkers potentially offer less invasive methods to aid early detection of oesophageal cancer. We aimed to systematically review studies assessing the relationship between nontissue biomarkers and subsequent development of oesophageal cancer.

METHODS

Using terms for biomarkers and oesophageal cancer, Medline, EMBASE and Web of Science were systematically searched for longitudinal studies, published until April 2016, which assessed the association between nontissue biomarkers and subsequent oesophageal cancer risk. Random effects meta-analyses were used to calculate pooled relative risk (RR) and 95% confidence intervals (CIs), where possible.

RESULTS

A total of 39 studies were included. Lower serum pepsinogen I concentrations were associated with an increased risk of oesophageal squamous cell carcinoma (n=3 studies, pooled RR=2.20, 95% CI: 1.31-3.70). However, the association for the pepsinogen I : II ratio was not statistically significant (n=3 studies, pooled RR=2.22, 95% CI: 0.77-6.40), with a large degree of heterogeneity observed (I=68.0%). Higher serum glucose concentrations were associated with a modestly increased risk of total oesophageal cancer (n=3 studies, pooled RR=1.27, 95% CI: 1.02-1.57). No association was observed for total cholesterol and total oesophageal cancer risk (n=3 studies, pooled RR=0.95, 95% CI: 0.58-1.54). Very few studies have assessed other biomarkers for meta-analyses.

CONCLUSION

Serum pepsinogen I concentrations could aid early detection of oesophageal squamous cell carcinoma. More prospective studies are needed to determine the use of other nontissue biomarkers in the early detection of oesophageal cancer.

The Epidemiology of Esophageal Adenocarcinoma

The incidence of esophageal adenocarcinoma (EAC) has increased in many Western countries and is higher in men than women. Some risk factors for EAC have been identified-mainly gastroesophageal reflux disease, Barrett's esophagus, obesity, and tobacco smoking. It is not clear whether interventions to address these factors can reduce risk of EAC, although some evidence exists for smoking cessation. Although consumption of alcohol is not associated with EAC risk, other exposures, such as physical activity, nutrition, and medication use, require further study. Genetic variants have been associated with risk for EAC, but their overall contribution is low. Studies are needed to investigate associations between risk factors and the molecular subtypes of EAC. The prognosis for patients with EAC has slightly improved, but remains poor-screening and surveillance trials of high-risk individuals are needed.

4-Nitroquinoline 1-Oxide-Induced Tongue and Esophagus Carcinogenesis in Obese and Diabetic TSOD Mice

Background

Obesity and diabetes mellitus are associated with lifestyle-related carcinogenesis. They are also risk factors of esophageal adenocarcinoma, but there are only a few reports on association between obesity/diabetes and development of squamous cell carcinoma in the oral cavity and esophagus. In this study, we therefore aimed to determine whether obesity and diabetes affect oral and esophageal carcinogenesis using model mice of obesity and diabetes, the Tsumura Suzuki obese diabetes (TSOD) and Tsumura Suzuki non-obesity (TSNO) control mice, which were treated with 4-nitroquinoline 1-oxide (4-NQO) to produce tongue and esophageal carcinomas.

Methods

We used 28 each of the male TSOD and TSNO mice of 8 weeks of age. They were divided into the 4-NQO-treated group (n = 20) and untreated group (n = 8). 4-NQO was administered to mice in drinking water at a dose level of 20 ppm for 8 weeks. The untreated group was given distilled water without 4-NQO. At 28 experimental weeks, histopathological examination was performed on all organs including tongue and esophagus. We performed analysis of histopathology of all organs which included buccal capsule (a tongue)/esophagus after an experiment start in 28 weeks. Fasting plasma glucose (FPG) and lipid parameters including total cholesterol (T-Cho), triglyceride (TG), high-density lipoprotein (HDL)-cholesterol and low-density lipoprotein (LDL)-cholesterol were measured and all these parameters were compared between the two genotypes. Also, mRNA expression of eight cytokines including interleukin (IL)-1β, IL-6, IL-17, interferon (IFN)-γ, keratinocyte-derived cytokine (KC), macrophage inflammatory protein (MIP)-1α, MIP-2, and tumor necrosis factor (TNF)-α in the esophageal mucosa was assayed.

Results

4-NQO treatment produced proliferative squamous cell lesions (dysplasia, papilloma and carcinoma) in the tongue and esophagus of both the TSOD and TSNO mice. The incidence and multiplicity of tongue tumors were 30% and 0.45 ± 0.83 in the TSOD mice and 30% and 0.40 ± 0.68 in the TSNO mice. The incidence and multiplicity of esophageal tumors were 70% and 2.25 ± 2.29 in the TSOD mice and 30% and 0.60 ± 1.14 (P < 0.01) in the TSNO mice.

Conclusion

Our findings indicate that the obese and diabetic TSOD mice were susceptible to 4-NQO-induced esophageal carcinogenesis, suggesting risk factors of obese and diabetes for esophageal squamous cell carcinoma. Additionally, the TSOD mice were useful as esophagus carcinogenic model. Our study first reported that 4-NQO induced esophageal cancer in mice.

The Annual Risk of Esophageal Adenocarcinoma Does Not Decrease Over Time in Patients With Barrett's Esophagus

OBJECTIVES

Endoscopic surveillance is recommended for patients with Barrett's esophagus (BE). However, it remains unclear if all BE patients benefit from long-term surveillance. We investigated the risk of esophageal adenocarcinoma (EAC) in BE patients in relation to number of successive endoscopies, years of follow-up, and calendar year.

METHODS

We conducted a retrospective cohort study of male veterans with newly diagnosed BE during 2004-2009 with follow-up until 30 September 2011. EAC was verified using detailed structured electronic medical records reviews. We used Poisson regression to determine incidence rates, rate ratios (RR), and corresponding 95% confidence intervals (CI) for EAC according to number of successive endoscopies, years of follow-up independent of number of follow-up endoscopies, and calendar year of BE diagnosis.

RESULTS

Among 28,561 male patients with BE, 406 developed EAC during 140,499 person-years of follow-up (median 4.9 years). EAC incidence rates increased with each additional endoscopy following a previous negative endoscopy (RR per additional endoscopy, 1.43; 95% CI, 1.25-1.64). Compared to the EAC incidence rate at the 1st follow-up EGD, the EAC incidence rate at the 5th follow-up EGD was ninefold higher (adjusted RR, 8.82; 95% CI, 4.90-15.9). EAC incidence was highest at the first year of follow-up (5.34 per 1,000 person-years); however, EAC rates starting from the second follow-up year increased during successive years of follow up. Compared to the EAC incidence rate in the 2nd year of follow-up, the EAC incidence rate was 1.5-fold higher in EGDs conducted ≥5 years after the index BE date (adjusted RR, 1.49; 95% CI, 1.07-2.10). In contrast, we found no significant change in EAC incidence rates by calendar year.

CONCLUSIONS

Persistence of non-neoplastic BE on multiple consecutive endoscopies was not associated with lower EAC risk. These findings argue against discontinuation of endoscopic surveillance in patients with persistent nondysplastic BE after multiple negative endoscopies.

Abdominal obesity and gastroesophageal cancer risk: systematic review and meta-analysis of prospective studies

To systematically and quantitatively review the relation of abdominal obesity, as measured by waist circumference (WC) and waist to hip ratio (WHR), to total gastroesophageal cancer, gastric cancer (GC), and esophageal cancer. PubMed and Web of Science databases were searched for studies assessing the association between abdominal obesity and gastroesophageal cancer (GC and/or esophageal cancer) up to August 2016. A random-effect model was used to calculate the summary relative risks (RRs) and 95% confidence intervals (CIs). Seven prospective cohort studies – one publication included two separate cohorts – from six publications were included in the final analysis. A total of 2130 gastroesophageal cancer cases diagnosed amongst 913182 participants. Higher WC and WHR were significantly associated with increased risk of total gastroesophageal cancer (WC: RR 1.68, 95% CI: 1.38, 2.04; WHR: RR 1.49, 95% CI: 1.19, 1.88), GC (WC: RR 1.48, 95% CI: 1.24, 1.78; WHR: 1.33, 95% CI: 1.04, 1.70), and esophageal cancer (WC: RR 2.06, 95% CI: 1.30, 3.24; WHR: RR 1.99, 95% CI: 1.05, 3.75).Findings from our subgroup analyses showed non-significant positive associations between gastric non-cardia adenocarcinoma (GNCA) and both measures of abdominal adiposity, while gastric cardia adenocarcinoma (GCA) was positively associated with WC but not with WHR. On analysis restricted to studies that adjusted for body mass index (BMI), WC was positively associated with GC and esophageal cancer, whereas WHR was positively associated with risk of GC only. Although limited, the findings from our meta-analysis suggest the potential role of abdominal obesity in the etiology of gastric and esophageal cancers.

Associations among Metabolism, Circadian Rhythm and Age-Associated Diseases

Accumulating epidemiological studies have implicated a strong link between age associated metabolic diseases and cancer, though direct and irrefutable evidence is missing. In this review, we discuss the connection between Warburg effects and tumorigenesis, as well as adaptive responses to environment such as circadian rhythms on molecular pathways involved in metabolism. We also review the central role of the sirtuin family of proteins in physiological modulation of cellular processes and age-associated metabolic diseases. We also provide a macroscopic view of how the circadian rhythm affects metabolism and may be involved in cell metabolism reprogramming and cancer pathogenesis. The aberrations in metabolism and the circadian system may lead to age-associated diseases directly or through intermediates. These intermediates may be either mutated or reprogrammed, thus becoming responsible for chromatin modification and oncogene transcription. Integration of circadian rhythm and metabolic reprogramming in the holistic understanding of metabolic diseases and cancer may provide additional insights into human diseases.

Gastrointestinal Complications of Obesity

Obesity usually is associated with morbidity related to diabetes mellitus and cardiovascular diseases. However, there are many gastrointestinal and hepatic diseases for which obesity is the direct cause (eg, nonalcoholic fatty liver disease) or is a significant risk factor, such as reflux esophagitis and gallstones. When obesity is a risk factor, it may interact with other mechanisms and result in earlier presentation or complicated diseases. There are increased odds ratios or relative risks of several gastrointestinal complications of obesity: gastroesophageal reflux disease, erosive esophagitis, Barrett's esophagus, esophageal adenocarcinoma, erosive gastritis, gastric cancer, diarrhea, colonic diverticular disease, polyps, cancer, liver disease including nonalcoholic fatty liver disease, cirrhosis, hepatocellular carcinoma, gallstones, acute pancreatitis, and pancreatic cancer. Gastroenterologists are uniquely poised to participate in the multidisciplinary management of obesity as physicians caring for people with obesity-related diseases, in addition to their expertise in nutrition and endoscopic interventions.

Obesity-associated digestive cancers: A review of mechanisms and interventions

The prevalence of obesity has steadily increased over the past few decades. Previous studies suggest that obesity is an oncogenic factor and that over 20% of all cancers are obesity-related. Among such cancers, digestive system malignancies (including esophageal adenocarcinomas, colorectal cancers, and cancers of the gastric cardia, liver, and pancreas) are reported most frequently. While the 5-year survival rates of cancers of the breast and prostate are 90%, that rate is only 45% for digestive cancers. In this review, the mechanisms of obesity-associated digestive cancers are discussed, with an emphasis on obesity-related gene mutations, insulin and insulin-like growth factor signaling pathways, chronic inflammation, and altered adipokine levels. Evidence that these factors often function interdependently rather than independently in carcinogenesis is presented. Recommended interventions that may reduce the burden of obesity-associated digestive cancers, such as participation in physical activity, diet modulation, and calorie restriction, are also described.

Risk stratification for malignant progression in Barrett’s esophagus: Gender, age, duration and year of surveillance

AIM

To clarify risk based upon segment length, diagnostic histological findings, patient age and year of surveillance, duration of surveillance and gender.

METHODS

Patients registered with the United Kingdom Barrett’s Oesophagus Registry from 9 United Kingdom centers were included. The outcome measures were (1) development of all grades of dysplasia; (2) development of high-grade of dysplasia or adenocarcinoma; and (3) development of adenocarcinoma. Prevalent cases and subjects with < 1 year of follow-up were excluded. The covariates examined were segment length, previous biopsy findings, age at surveillance, duration of surveillance, year of surveillance and gender.

RESULTS

One thousand and one hundred thirty six patients were included (total 6474 patient-years). Fifty-four patients developed adenocarcinoma (0.83% per annum), 70 developed high-grade dysplasia/adenocarcinoma (1.1% per annum) and 190 developed any grade of dysplasia (3.5% per annum). High grade dysplasia and adenocarcinoma increased with age and duration of surveillance. The risk of low-grade dysplasia development was not dependent on age at surveillance. Segment length and previous biopsy findings were also significant factors for development of dysplasia and adenocarcinoma.

CONCLUSION

The risk of development of low-grade dysplasia is independent of age at surveillance, but high-grade dysplasia and adenocarcinoma were more commonly found at older age. Segment length and previous biopsy findings are also markers of risk. This study did not demonstrate stabilisation of the metaplastic segment with prolonged surveillance.

Is Obesity Associated with Barrett's Esophagus and Esophageal Adenocarcinoma?

Barrett's esophagus is a premalignant condition portending increased risk of esophageal adenocarcinoma. Given the significant morbidity and mortality of esophageal adenocarcinoma, identification of risk factors for Barrett's esophagus and esophageal adenocarcinoma is crucial. There are a plethora of studies investigating the relationship of obesity with these pathologies. Recent studies reveal that this relationship may specifically be with central adiposity. Increased cell turnover and eventual carcinogenesis is likely precipitated by increased intragastric pressure but also is affected by the complex interplay of increased insulin resistance in patients with increased fat tissue. Further studies are warranted to evaluate if weight loss can decrease progression of Barrett's esophagus.

Diabetic biomarkers and the risk of proximal or distal gastric cancer

BACKGROUND AND AIM

The role of diabetes mellitus as a risk factor for gastric cancer has been controversial. We studied the association between diabetic biomarkers and the risk of gastric cancer and whether these associations depend on cancer location.

METHODS

In this retrospective cohort study with subjects with negative initial esophagogastroduodenoscopy findings (n = 23 218) during a routine health checkup, we measured fasting glucose and insulin levels, calculated the homeostatic model assessment insulin resistance (HOMA-IR) values, and analyzed the risk of gastric cancer in relation to diabetic biomarker tertiles and the presence of diabetes mellitus.

RESULTS

The incidence rate of gastric cancer was 9.7 per 10 000 person-years during the mean 6.8-year follow up. Patients with diabetes, higher fasting glucose levels, or higher HOMA-IR levels were older; men, current smokers, and heavy alcohol consumers represented larger proportions of these groups. They also had high body mass index and hemoglobin A1c more often. In the multivariate-adjusted Cox regression analyses, the incidence of gastric cancer was not significantly associated with diabetes mellitus or higher diabetic biomarker levels. Compared with normal glucose levels, lower glucose levels were significantly associated with an increased risk of distal gastric cancer. The hazard ratio for fasting glucose level tertile 1 was 2.39 (95% confidence interval, 1.48-3.85) (reference, tertile 2). Lower glucose levels were not associated with a risk of proximal gastric cancer, compared with a normal glucose level.

CONCLUSIONS

Our findings suggest that fasting glucose levels have a different effect on distal and proximal gastric cancers.

Progression of Barrett's esophagus toward esophageal adenocarcinoma: an overview

In Barrett's esophagus, normal squamous epithelium is replaced by a metaplastic columnar epithelium as a consequence of chronic gastroesophageal reflux disease. There is a strong association with esophageal adenocarcinoma. In view of the increasing incidence of esophageal adenocarcinoma in the western world, it is important that more attention be paid to the progression of Barrett's esophagus toward esophageal adenocarcinoma. Recently, several molecular factors have been identified that contribute to the sequence towards adenocarcinoma. This might help identify patients at risk and detect new targets for the prevention and treatment of esophageal adenocarcinoma in the future.