Barrett's esophagus

New dimensions of electrospun nanofiber material designs for biotechnological uses

Electrospinning technology has garnered wide attention over the past few decades in various biomedical applications including drug delivery, cell therapy, and tissue engineering. This technology can create nanofibers with tunable fiber diameters and functionalities. However, the 2D membrane nature of the nanofibers, as well as the rigidity and low porosity of electrospun fibers, lower their efficacy in tissue repair and regeneration. Recently, new avenues have been explored to resolve the challenges associated with 2D electrospun nanofiber membranes. This review discusses recent trends in creating different electrospun nanofiber microstructures from 2D nanofiber membranes by using various post-processing methods, as well as their biotechnological applications.

Chemoprevention of esophageal adenocarcinoma in a rat surgical model by a cysteinyl leukotriene receptor‑1 antagonist

Reflux of gastroduodenal contents into the esophagus leads to the development of esophagitis and inflammation-associated pathologies, such as Barrett's esophagus (BE) and esophageal adenocarcinoma (EAC). The role of the lipoxygenase (LOX) pathway in carcinogenesis has been recently reported; however, its involvement in esophageal carcinogenesis remains unclear. To address this, the present study investigated the potential of pranlukast, a cysteinyl leukotriene receptor-1 antagonist, to suppress the progression of BE and EAC in a rat duodenogastroesophageal reflux (DGER) model. Male Wistar rats that underwent DGER were divided into two groups. One group was fed commercial chow (control group), and the other was fed experimental chow containing pranlukast (pranlukast group). The rats were sacrificed at 10, 20, 30 and 40 weeks after surgery, and their esophagi were examined. Expression levels of 5-LOX, CD68, IL-8, VEGF and Ki-67 were investigated using immunohistochemistry, and apoptosis was analyzed using the TUNEL method. In the pranlukast group, esophagitis was milder, and the incidence of BE and EAC was significantly lower (P<0.05) compared with that in the control group at 40 weeks after surgery. The number of cells positive for IL-8 and VEGF were significantly lower in the pranlukast group compared with the control group. Proliferative activity was also lower in the pranlukast group compared with the control group (P<0.05). Pranlukast treatment increased apoptosis (P<0.05). Overall, Pranlukast suppressed esophageal carcinogenesis in a rat DGER model, decreasing inflammatory cytokines such as IL-8 and VEGF.

Variation in proliferative and cell cycle markers in Barrett's esophagus in relation to circumferential and axial location in the esophagus

BACKGROUND

Adenocarcinoma in Barrett's esophagus (BE) occurs more frequently between 12 and 3 o'clock at the gastroesophageal junction (GEJ).

METHODS

BE patients were prospectively recruited from December 2013 to July 2016. Expression of p53, Ki-67, cyclin-D1, COX-2 and p21 was assessed in quadrantic biopsies from the proximal and distal margins of the BE segments. Cell cycle marker association with current or subsequent dysplasia or adenocarcinoma was examined.

RESULTS

110 patients: median age 64 (IQR, 56-71) years; median BE segment length C4M6; and a median follow-up of 4.7 (IQR, 3.6-5.7) years. In total 13 (11.8%) had evidence of dysplasia or neoplasia (2.7% indefinite for dysplasia, 5.5% low grade, 1.8% high grade and 1.8% adenocarcinoma) at index endoscopy. Six (7%) developed dysplasia or neoplasia (1 low grade, 2 high grade and 3 adenocarcinoma) during follow-up. Ki-67 expression was highest at 3 o'clock, and overall was 49.6% higher in the 12-6 o'clock position compared to 6-12 o'clock [odds ratio (OR), 1.42 (95% confidence interval (CI), 1.00-2.12)]. A similar pattern was found with p21 [1.82 (1.00-3.47)]. There was increased expression of several markers in distal BE biopsies; cyclin-D1 [1.74 (1.29-2.34)]; Cyclo-oxygenase 2 [2.03 (1.48-2.78]) and p21 [2.06 (1.16-3.68)]. Expression of Ki-67 was lower in distal compared to proximal biopsies [0.58 (0.43-0.78)]. P53 expression had high specificity (93.8%) for subsequent low-grade dysplasia, high-grade dysplasia or adenocarcinoma.

CONCLUSION

Increased cellular proliferation was seen at 12-6 o'clock at the GEJ. Cell-cycle marker expression was increased at the GEJ compared to the proximal BE segment. These findings mirror reflux esophagitis and suggest ongoing reflux contributes to the progression of dysplasia and malignancy in BE.

A Delphi Method for Development of a Barrett's Esophagus Question Prompt List as a Communication Tool for Optimal Patient-physician Communication

BACKGROUND METHODS

The question prompt list content was derived through a modified Delphi process consisting of 3 rounds. In round 1, experts provided 5 answers to the prompts "What general questions should patients ask when given a new diagnosis of Barrett's esophagus" and "What questions do I not hear patients asking, but given my expertise, I believe they should be asking?" Questions were reviewed and categorized into themes. In round 2, experts rated questions on a 5-point Likert scale. In round 3, experts rerated questions modified or reduced after the previous rounds. Only questions rated as "essential" or "important" were included in Barrett's esophagus question prompt list (BE-QPL). To improve usability, questions were reduced to minimize redundancy and simplified to use language at an eighth-grade level (Fig. 1).

RESULTS

Twenty-one esophageal medical and surgical experts participated in both rounds (91% males; median age 52 years). The expert panel comprised of 33% esophagologists, 24% foregut surgeons, and 24% advanced endoscopists, with a median of 15 years in clinical practice. Most (81%), worked in an academic tertiary referral hospital. In this 3-round Delphi technique, 220 questions were proposed in round 1, 122 (55.5%) were accepted into the BE-QPL and reduced down to 76 questions (round 2), and 67 questions (round 3). These 67 questions reached a Flesch Reading Ease of 68.8, interpreted as easily understood by 13 to 15 years olds.

CONCLUSIONS

With multidisciplinary input, we have developed a physician-derived BE-QPL to optimize patient-physician communication. Future directions will seek patient feedback to distill the questions further to a smaller number and then assess their usability.

The Multidisciplinary Approach and Surgical Management of GE Junction Adenocarcinoma

Gastroesophageal (GE) junction adenocarcinoma is an aggressive malignancy of growing incidence and is associated with public health issues such as obesity and GERD. Management has evolved over the last two decades to incorporate a multidisciplinary approach, including endoscopic intervention, neoadjuvant chemotherapy/chemoradiation, and minimally invasive or more limited surgical approaches. Surgical approaches include esophagectomy, total gastrectomy, and, more recently, proximal gastrectomy. This review analyzes the evidence for and applicability of these varied approaches in management, as well as areas of continued controversy and investigation.

Low-grade dysplasia in Barrett's esophagus: A problematic diagnosis

Although low-grade dysplasia (LGD) in Barrett's esophagus (BE) is a histopathological diagnosis based on different histological abnormalities, it is still problematic for different reasons. Patients without confirmed diagnosis of LGD undergo unnecessary and intensified follow-up where the risk of progression is low in the majority of cases. In contrast, the presence of confirmed LGD indicates a high risk of progression. In this article we try to address these reasons focusing on re-confirmation of LGD diagnosis, interobserver agreement, and persistent confirmed LGD. The progression risk of LGD to high-grade dysplasia and esophageal adenocarcinoma will also be reviewed.

Professionals' views on the justification for esophageal adenocarcinoma screening: A systematic literature search and qualitative analysis

Screening for early esophageal adenocarcinoma (EAC), including screening for its precursor Barrett's esophagus (BE), has the potential to reduce EAC-related mortality and morbidity. This literature review aimed to explore professionals' views on the justification for EAC screening. A systematic search of Ovid Medline, EMBASE, and PsycInfo, from January 1, 2000 to September 22, 2022, identified 5 original studies and 63 expert opinion articles reporting professionals' perspectives on EAC screening. Included articles were qualitatively analyzed using the framework method, which was deductively led by modernized screening principles. The analyses showed that many professionals are optimistic about technological advancements in BE detection and treatment. However, views on whether the societal burden of EAC merits screening were contradictory. In addition, knowledge of the long-term benefits and risks of EAC screening is still considered insufficient. There is no consensus on who to screen, how often to screen, which screening test to use, and how to manage non-dysplastic BE. Professionals further point out the need to develop technology that facilitates automated test sample processing and public education strategies that avoid causing disproportionately high cancer worry and social stigma. In conclusion, modernized screening principles are currently insufficiently fulfilled to justify widespread screening for EAC. Results from future clinical screening trials and risk prediction modeling studies may shift professionals' thoughts regarding justification for EAC screening.

Downregulation of SODD mediates carnosol-induced reduction in cell proliferation in esophageal adenocarcinoma cells

Esophageal adenocarcinoma carries a poor prognosis associated with a 5-year survival rate of 12.5-20%. Therefore, a new therapeutic modality is needed for this lethal tumor. Carnosol is a phenolic diterpene purified from the herbs such as rosemary and Mountain desert sage and has been shown to have anticancer activities in multiple cancers. In this study we examined the effect of carnosol on cell proliferation in esophageal adenocarcinoma cells. We found that carnosol dose-dependently decreased cell proliferation in FLO-1 esophageal adenocarcinoma cells and significantly increased caspase-3 protein, indicating that carnosol decreases cell proliferation and increases cell apoptosis in FLO-1 cells. Carnosol significantly increased H2O2 production and N-acetyl cysteine, a reactive oxygen species (ROS) scavenger, significantly inhibited carnosol-induced decrease in cell proliferation, indicating that ROS may mediate carnosol-induced decrease in cell proliferation. Carnosol-induced decrease in cell proliferation was partially reversed by NADPH oxidase inhibitor apocynin, suggesting that NADPH oxidases may be partially involved in carnosol's effect. In addition, carnosol significantly downregulated SODD protein and mRNA expression and knockdown of SODD significantly inhibited the carnosol-induced reduction in cell proliferation, suggesting that downregulation of SODD may contribute to carnosol-induced reduction in cell proliferation. We conclude that carnosol dose-dependently decreased cell proliferation and significantly increased caspase-3 protein. Carnosol's effect may be through the overproduction of ROS and the downregulation of SODD. Carnosol might be useful for the treatment of esophageal adenocarcinoma.

What has the past taught us about the future in esophageal cancer? Personal reflections

Since the first successful esophagectomy for cancer in 1913 spectacular advancements have been made in diagnosis, staging, and therapy. Refinement of imaging, surgery, perioperative management together with multidisciplinary collaboration are the cornerstones. Today therapy with curative option is offered to more patients than ever. Further innovations in imaging, molecular biology, genetics, artificial intelligence, machine learning, robotics, nanotechnology will have an increasing impact. The end result being a unique therapeutic plan shaped on each patient's individual profile.

P63 Deficiency and CDX2 Overexpression Lead to Barrett's-Like Metaplasia in Mouse Esophageal Epithelium

BACKGROUND

The cellular origin and molecular mechanisms of Barrett's esophagus (BE) are still controversial. Trans-differentiation is a mechanism characterized by activation of the intestinal differentiation program and inactivation of the squamous differentiation program.

AIMS

Renal capsule grafting (RCG) was used to elucidate whether CDX2 overexpression on the basis of P63 deficiency in the esophageal epithelium may generate intestinal metaplasia.

METHODS

P63^-/-;Villin-Cdx2 embryos were generated by crossing P63^+/- mice with Villin-Cdx2 mice. E18.5 esophagus was xenografted in a renal capsule grafting (RCG) model. At 1, 2, or 4 weeks after RCG, the mouse esophagus was immunostained for a proliferation marker (BrdU), squamous transcription factors (SOX2, PAX9), squamous differentiation markers (CK5, CK4, and CK1), intestinal transcription factors (CDX1, HNF1α, HNF4α, GATA4, and GATA6), intestinal columnar epithelial cell markers (A33, CK8), goblet cell marker (MUC2, TFF3), Paneth cell markers (LYZ and SOX9), enteroendocrine cell marker (CHA), and Tuft cell marker (DCAMKL1).

RESULTS

The P63^-/-;Villin-Cdx2 RCG esophagus was lined with proliferating PAS/AB+ cuboidal cells and formed an intestinal crypt-like structure. The goblet cell markers (TFF3 and MUC2) and intestinal transcription factors (CDX1, HNF1α, HNF4α, GATA4, and GATA6) were expressed although no typical morphology of goblet cells was observed. Other intestinal cell markers including enteroendocrine cell marker (CHA), Paneth cell markers (LYZ and Sox9), and intestinal secretory cell marker (UEA/WGA) were also expressed in the P63^-/-;Villin-Cdx2 RCG esophagus. Squamous cell markers (PAX9 and SOX2) were also expressed, suggesting a transitional phenotype.

CONCLUSION

CDX2 overexpression on the basis of P63 deficiency in esophageal epithelial cells induces Barrett's-like metaplasia in vivo. Additional factors may be needed to drive this transitional phenotype into full-blown BE.

High-Fructose Diet Alters Intestinal Microbial Profile and Correlates with Early Tumorigenesis in a Mouse Model of Barrett’s Esophagus

Esophageal adenocarcinoma (EAC) is mostly prevalent in industrialized countries and has been associated with obesity, commonly linked with a diet rich in fat and refined sugars containing high fructose concentrations. In meta-organisms, dietary components are digested and metabolized by the host and its gut microbiota. Fructose has been shown to induce proliferation and cell growth in pancreas and colon cancer cell lines and also alter the gut microbiota. In a previous study with the L2-IL-1B mouse model, we showed that a high-fat diet (HFD) accelerated EAC progression from its precursor lesion Barrett’s esophagus (BE) through changes in the gut microbiota. Aiming to investigate whether a high-fructose diet (HFrD) also alters the gut microbiota and favors EAC carcinogenesis, we assessed the effects of HFrD on the phenotype and intestinal microbial communities of L2-IL1B mice. Results showed a moderate acceleration in histologic disease progression, a mild effect on the systemic inflammatory response, metabolic changes in the host, and a shift in the composition, metabolism, and functionality of intestinal microbial communities. We conclude that HFrD alters the overall balance of the gut microbiota and induces an acceleration in EAC progression in a less pronounced manner than HFD.

Screening for Barrett's Oesophagus: Are We Ready for it?

Purpose of review

The targeted approach adopted for Barrett’s oesophagus (BO) screening is sub-optimal considering the large proportion of BO cases that are currently missed. We reviewed the literature highlighting recent technological advancements in efforts to counteract this challenge. We also provided insights into strategies that can improve the outcomes from current BO screening practises.

Recent findings

The standard method for BO detection, endoscopy, is invasive and expensive and therefore inappropriate for mass screening. On the other hand, endoscopy is more cost-effective for screening a high-risk population. A consensus has however not been reached on who should be screened. Risk prediction algorithms have been tested as an enrichment pre-screening tool reporting modest AUC’s but require more prospective evaluation studies. Less invasive endoscopy methods like trans-nasal endoscopy, oesophageal capsule endsocopy and non-endoscopic cell collection devices like the Cytosponge coupled with biomarker analysis have shown promise in BO detection with randomised clinical trial evidence.

Summary

A three-tier precision cancer programme whereby risk prediction algorithms and non-endoscopic minimally invasive cell collection devices are used to triage test a wider pool of individuals may improve the detection rate of current screening practises with minimal cost implications.

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.

Interaction of epidermal growth factor with COX-2 products and peroxisome proliferator-activated receptor-γ system in experimental rat Barrett's esophagus

Mixed acidic-alkaline refluxate is a major pathogenic factor in chronic esophagitis progressing to Barrett's esophagus (BE). We hypothesized that epidermal growth factor (EGF) can interact with COX-2 and peroxisome proliferator-activated receptor-γ (PPARγ) in rats surgically prepared with esophagogastroduodenal anastomosis (EGDA) with healthy or removed salivary glands to deplete salivary EGF. EGDA rats were treated with 1) vehicle, 2) EGF or PPARγ agonist pioglitazone with or without EGFR kinase inhibitor tyrphostin A46, EGF or PPARγ antagonist GW9662 respectively, 3) ranitidine or pantoprazole, and 4) the selective COX-2 inhibitor celecoxib combined with pioglitazone. At 3 mo, the esophageal damage and the esophageal blood flow (EBF) were determined, the mucosal expression of EGF, EGFR, COX-2, TNFα, and PPARγ mRNA and phospho-EGFR/EGFR protein was analyzed. All EGDA rats developed chronic esophagitis, esophageal ulcerations, and intestinal metaplasia followed by a fall in the EBF, an increase in the plasma of IL-1β, TNFα, and mucosal PGE₂ content, the overexpression of COX-2-, and EGF-EGFR mRNAs, and proteins, and these effects were aggravated by EGF and attenuated by pioglitazone. The rise in EGF and COX-2 mRNA was inhibited by pioglitazone but reversed by pioglitazone cotreated with GW9662. We conclude that 1) EGF can interact with PG/COX-2 and the PPARγ system in the mechanism of chronic esophagitis; 2) the deleterious effect of EGF involves an impairment of EBF and the overexpression of COX-2 and EGFR, and 3) agonists of PPARγ and inhibitors of EGFR may be useful in the treatment of chronic esophagitis progressing to BE.NEW & NOTEWORTHY Rats with EGDA exhibited chronic esophagitis accompanied by a fall in EBF and an increase in mucosal expression of mRNAs for EGF, COX-2, and TNFα, and these effects were exacerbated by exogenous EGF and reduced by removal of a major source of endogenous EGF with salivectomy or concurrent treatment with tyrphostin A46 or pioglitazone combined with EGF. Beneficial effects of salivectomy in an experimental model of BE were counteracted by PPARγ antagonist, whereas selective COX-2 inhibitor celecoxib synergistically with pioglitazone reduced severity of esophageal damage and protected esophageal mucosa from reflux. We propose the cross talk among EGF/EGFR, PG/COX-2, and proinflammatory cytokines with PPARγ pathway in the mechanism of pathogenesis of chronic esophagitis progressing to BE and EAC.

Intestinal Stem Cell Aging: Origins and Interventions

Regenerative processes that maintain the function of the gastrointestinal (GI) epithelium are critical for health and survival of multicellular organisms. In insects and vertebrates, intestinal stem cells (ISCs) regenerate the GI epithelium. ISC function is regulated by intrinsic, local, and systemic stimuli to adjust regeneration to tissue demands. These control mechanisms decline with age, resulting in significant perturbation of intestinal homeostasis. Processes that lead to this decline have been explored intensively in Drosophila melanogaster in recent years and are now starting to be characterized in mammalian models. This review presents a model for age-related regenerative decline in the fly intestine and discusses recent findings that start to establish molecular mechanisms of age-related decline of mammalian ISC function.

Barrett Esophagus Length, Nodularity, and Low-grade Dysplasia are Predictive of Progression to Esophageal Adenocarcinoma

GOALS

To investigate factors predictive of progression from nondysplastic Barrett esophagus (NDBE) or low-grade dysplasia (LGD) to high-grade dysplasia (HGD) or esophageal adenocarcinoma (EAC) using a large, prospective cohort of patients, wherein all esophageal biopsies undergo expert gastrointestinal pathologist review.

BACKGROUND

Efficacy and cost-effectiveness of endoscopic surveillance to detect incident EAC in the setting of Barrett esophagus (BE), particularly in NDBE patients, is questioned. Previous studies have reported factors predictive of progression to EAC to guide surveillance intervals, but their strength is limited by small sample size and absence of expert gastrointestinal pathologist involvement in esophageal biopsy review.

STUDY

NDBE and LGD subjects were identified from a prospective registry in a tertiary care center. "Progressors" were BE subjects who developed HGD/EAC>12 months after the initial NDBE or LGD diagnosis. Cox proportional hazards model were used to identify predictors of progression.

RESULTS

In total, 318 with NDBE and 301 with BE-LGD (mean age, 62.6 y, 85% male) were included. The mean follow-up was 5.3 years. The 7 NDBE and 21 LGD subjects progressed to HGD/EAC. BE length [hazards ratio (HR), 1.16; 95% confidence interval (CI), 1.03-1.29], presence of nodularity (HR, 4.98; 95% CI, 1.80-11.7), and baseline LGD (HR, 2.57; 95% CI, 1.13-6.57) were significant predictors of progression on multivariate analysis.

CONCLUSIONS

In this well-defined cohort of NDBE and BE-LGD subjects, BE length, presence of LGD, and nodularity were independent predictors of progression to HGD/EAC. These factors may aid in identifying high-risk patients who may benefit from closer endoscopic surveillance/therapy.

Endoscopic therapy for confirmed low-grade dysplasia in Barrett's esophagus

Barrett's esophagus (BE) is a premalignant condition characterized by replacement of the esophageal lining with metastatic columnar epithelium. To date, the management in case of confirmed low-grade dysplasia (LGD) remains controversial. In this article we summarize the available endoscopic options and their results in terms of efficacy and safety in the treatment of confirmed LGD in BE.

Buried Barrett's Esophagus with High-Grade Dysplasia after Radiofrequency Ablation

Radiofrequency ablation therapy is an effective endoscopic option for the eradication of Barrett’s esophagus that appears to reduce the risk of esophageal cancer. A concern associated with this technique is the development of subsquamous/buried intestinal metaplasia, whose clinical relevance and malignant potential have not yet been fully elucidated. Fewer than 20 cases of subsquamous neoplasia after the successful radiofrequency ablation of Barrett’s esophagus have been reported to date. Here, we describe a new case of subsquamous neoplasia (high-grade dysplasia) following radiofrequency ablation that was managed with endoscopic resection. Our experience suggests that a meticulous endoscopic inspection prior to and after radiofrequency ablation is fundamental to reduce the risk of buried neoplasia development.

Helicobacter pylori induces caudal-type homeobox protein 2 and cyclooxygenase 2 expression by modulating microRNAs in esophageal epithelial cells

Dysregulation of microRNAs (miRNAs) has been linked to virulence factors of Helicobacter pylori. The role of H. pylori in esophageal disease has not been clearly defined. We previously reported that H. pylori esophageal colonization promotes the incidence of Barrett's esophagus and esophageal adenocarcinoma in vivo. Here, we studied the direct effects of H. pylori on the transformation of esophageal epithelial cells, with particular focus on whether H. pylori exerts its effects by modulating miRNAs and their downstream target genes. The normal human esophageal cell line HET‐1A was chronically exposed to H. pylori extract and/or acidified deoxycholic acid for up to 36 weeks. The miRNA profiles of the esophageal epithelial cells associated with H. pylori infection were determined by microarray analysis. We found that chronic H. pylori exposure promoted acidified deoxycholic acid‐induced morphological changes in HET‐1A cells, along with aberrant overexpression of intestinal metaplasia markers and tumorigenic factors, including caudal‐type homeobox protein 2 (CDX2), mucin 2, and cyclooxygenase 2 (COX2). Helicobacter pylori modified the miRNA profiles of esophageal epithelial cells, particularly aberrant silencing of miR‐212‐3p and miR‐361‐3p. Moreover, in biopsies from Barrett's esophagus patients, esophageal H. pylori colonization was associated with a significant decrease in miR‐212‐3p and miR‐361‐3p expression. Furthermore, we identified COX2 as a target of miR‐212‐3p, and CDX2 as a target of miR‐361‐3p. Helicobacter pylori infection of esophageal epithelial cells was associated with miRNA‐mediated upregulation of oncoprotein CDX2 and COX2. Our observations provide new evidence about the molecular mechanisms underlying the association between H. pylori infection and esophageal carcinogenesis.

CXCR4 Is a Potential Target for Diagnostic PET/CT Imaging in Barrett's Dysplasia and Esophageal Adenocarcinoma

Purpose: Barrett's esophagus represents an early stage in carcinogenesis leading to esophageal adenocarcinoma. Considerable evidence supports a major role for chronic inflammation and diverse chemokine pathways in the development of Barrett's esophagus and esophageal adenocarcinoma.Experimental Design: Here we utilized an IL1β transgenic mouse model of Barrett's esophagus and esophageal adenocarcinoma and human patient imaging to analyze the importance of CXCR4-expressing cells during esophageal carcinogenesis.Results: IL1β overexpression induces chronic esophageal inflammation and recapitulates the progression to Barrett's esophagus and esophageal adenocarcinoma. CXCR4 expression is increased in both epithelial and immune cells during disease progression in pL2-IL1β mice and also elevated in esophageal adenocarcinoma patient biopsy samples. Specific recruitment of CXCR4-positive (CXCR4⁺) immune cells correlated with dysplasia progression, suggesting that this immune population may be a key contributor to esophageal carcinogenesis. Similarly, with progression to dysplasia, there were increased numbers of CXCR4⁺ columnar epithelial cells at the squamocolumnar junction (SCJ). These findings were supported by stronger CXCR4-related signal intensity in ex vivo fluorescence imaging and autoradiography with advanced dysplasia. Pilot CXCR4-directed PET/CT imaging studies in patients with esophageal cancer demonstrate the potential utility of CXCR4 imaging for the diagnosis and staging of esophageal cancer.Conclusion: In conclusion, the recruitment of CXCR4⁺ immune cells and expansion of CXCR4⁺ epithelial cells in esophageal dysplasia and cancer highlight the potential of CXCR4 as a biomarker and molecular target for diagnostic imaging of the tumor microenvironment in esophageal adenocarcinoma. Clin Cancer Res; 24(5); 1048-61. ©2017 AACR.

Interorgan regulation of Drosophila intestinal stem cell proliferation by a hybrid organ boundary zone

The molecular identities and regulation of cells at interorgan boundaries are often unclear, despite the increasingly appreciated role of organ boundaries in disease. Using Drosophila as a model, we here show that a specific population of adult midgut organ-boundary intestinal stem cells (OB-ISCs) is regulated by the neighboring hindgut, a developmentally distinct organ. This distinct OB-ISC control occurs through proximity to a specialized transition zone between the endodermal midgut and ectodermal hindgut that shares molecular signatures of both organs, which we term the hybrid zone (HZ). During homeostasis, proximity to the HZ restrains OB-ISC proliferation. However, injury to the adult HZ/hindgut drives upregulation of unpaired-3 cytokine, which signals through a Signal transducer and activator of transcription (STAT) protein to promote cell division only in OB-ISCs. If HZ disruption is severe, hyperplastic OB-ISCs expand across the interorgan boundary. Our data suggest that interorgan signaling plays an important role in controlling OB-ISCs in homeostasis and injury repair, which is likely to be crucial in prevention of disease.

Genomic regions associated with susceptibility to Barrett's esophagus and esophageal adenocarcinoma in African Americans: The cross BETRNet admixture study

Background

Barrett’s esophagus (BE) and esophageal adenocarcinoma (EAC) are far more prevalent in European Americans than in African Americans. Hypothesizing that this racial disparity in prevalence might represent a genetic susceptibility, we used an admixture mapping approach to interrogate disease association with genomic differences between European and African ancestry.

Methods

Formalin fixed paraffin embedded samples were identified from 54 African Americans with BE or EAC through review of surgical pathology databases at participating Barrett’s Esophagus Translational Research Network (BETRNet) institutions. DNA was extracted from normal tissue, and genotyped on the Illumina OmniQuad SNP chip. Case-only admixture mapping analysis was performed on the data from both all 54 cases and also on a subset of 28 cases with high genotyping quality. Haplotype phases were inferred with Beagle 3.3.2, and local African and European ancestries were inferred with SABER plus. Disease association was tested by estimating and testing excess European ancestry and contrasting it to excess African ancestry.

Results

Both datasets, the 54 cases and the 28 cases, identified two admixture regions. An association of excess European ancestry on chromosome 11p reached a 5% genome-wide significance threshold, corresponding to -log₁₀(P) = 4.28. A second peak on chromosome 8q reached -log₁₀(P) = 2.73. The converse analysis examining excess African ancestry found no genetic regions with significant excess African ancestry associated with BE and EAC. On average, the regions on chromosomes 8q and 11p showed excess European ancestry of 15% and 20%, respectively.

Conclusions

Chromosomal regions on 11p15 and 8q22-24 are associated with excess European ancestry in African Americans with BE and EAC. Because GWAS have not reported any variants in these two regions, low frequency and/or rare disease associated variants that confer susceptibility to developing BE and EAC may be driving the observed European ancestry association evidence.

TGR5 expression in benign, preneoplastic and neoplastic lesions of Barrett’s esophagus: Case series and findings

AIM

To examined the bile acid receptor TGR5 expression in squamous mucosa, Barrett’s mucosa, dysplasia and esophageal adenocarcinoma (EA).

METHODS

Slides were stained with TGR5 antibody. The staining intensity was scored as 1+, 2+ and 3+. The extent of staining (percentage of cells staining) was scored as follows: 1+, 1%-10%, 2+, 11%-50%, 3+, 51%-100%. A combined score of intensity and extent was calculated and categorized as negative, weak, moderate and strong staining. TGR5 mRNA was measured by real time PCR.

RESULTS

We found that levels of TGR5 mRNA were significantly increased in Barrett’s dysplastic cell line CP-D and EA cell line SK-GT-4, when compared with Barrett’s cell line CP-A. Moderate to strong TGR5 staining was significantly higher in high-grade dysplasia and EA cases than in Barrett’s esophagus (BE) or in low-grade dysplasia. Moderate to strong staining was slightly higher in low-grade dysplasia than in BE mucosa, but there is no statistical significance. TGR5 staining had no significant difference between high-grade dysplasia and EA. In addition, TGR5 staining intensity was not associated with the clinical stage, the pathological stage and the status of lymph node metastasis.

CONCLUSION

We conclude that TGR5 immunostaining was much stronger in high-grade dysplasia and EA than in BE mucosa or low-grade dysplasia and that its staining intensity was not associated with the clinical stage, the pathological stage and the status of lymph node metastasis. TGR5 might be a potential marker for the progression from BE to high-grade dysplasia and EA.

Hnf4α is a key gene that can generate columnar metaplasia in oesophageal epithelium

Barrett's metaplasia is the only known morphological precursor to oesophageal adenocarcinoma and is characterized by replacement of stratified squamous epithelium by columnar epithelium. The cell of origin is uncertain and the molecular mechanisms responsible for the change in cellular phenotype are poorly understood. We therefore explored the role of two transcription factors, Cdx2 and HNF4α in the conversion using primary organ cultures. Biopsy samples from cases of human Barrett's metaplasia were analysed for the presence of CDX2 and HNF4α. A new organ culture system for adult murine oesophagus is described. Using this, Cdx2 and HNF4α were ectopically expressed by adenoviral infection. The phenotype following infection was determined by a combination of PCR, immunohistochemical and morphological analyses. We demonstrate the expression of CDX2 and HNF4α in human biopsy samples. Our oesophageal organ culture system expressed markers characteristic of the normal SSQE: p63, K14, K4 and loricrin. Ectopic expression of HNF4α, but not of Cdx2 induced expression of Tff3, villin, K8 and E-cadherin. HNF4α is sufficient to induce a columnar-like phenotype in adult mouse oesophageal epithelium and is present in the human condition. These data suggest that induction of HNF4α is a key early step in the formation of Barrett's metaplasia and are consistent with an origin of Barrett's metaplasia from the oesophageal epithelium.

Esophageal adenocarcinoma and Barrett esophagus in a neurologically impaired teenager

Esophageal adenocarcinoma (EAC) accompanied by Barrett esophagus (BE) is rare in patients younger than 20 years old. EAC in the upper esophagus is also rare. We report a rare case of EAC with BE that developed in the upper esophagus after chronic, untreated gastroesophageal reflux disease in a neurologically impaired teenager. A 19-year-old neurologically impaired man underwent endoscopy for evaluation of dysphagia and vomiting, and was diagnosed with EAC with BE. He underwent transthoracic esophagectomy, extensive lymph node dissection, and cervical esophagogastric anastomosis, but the prognosis was poor. Pathology indicated poorly differentiated adenocarcinoma with BE.

Overview of major molecular alterations during progression from Barrett's esophagus to esophageal adenocarcinoma

Esophageal adenocarcinoma (EAC) develops in the sequential transformation of normal epithelium into metaplastic epithelium, called Barrett's esophagus (BE), then to dysplasia, and finally cancer. BE is a common condition in which normal stratified squamous epithelium of the esophagus is replaced with an intestine-like columnar epithelium, and it is the most prominent risk factor for EAC. This review aims to impartially systemize the knowledge from a large number of publications that describe the molecular and biochemical alterations occurring over this progression sequence. In order to provide an unbiased extraction of the knowledge from the literature, a text-mining methodology was used to select genes that are involved in the BE progression, with the top candidate genes found to be TP53, CDKN2A, CTNNB1, CDH1, GPX3, and NOX5. In addition, sample frequencies across analyzed patient cohorts at each stage of disease progression are summarized. All six genes are altered in the majority of EAC patients, and accumulation of alterations correlates well with the sequential progression of BE to cancer, indicating that the text-mining method is a valid approach for gene prioritization. This review discusses how, besides being cancer drivers, these genes are functionally interconnected and might collectively be considered a central hub of BE progression.

Gastrointestinal stem cells in health and disease: from flies to humans

The gastrointestinal tract of complex metazoans is highly compartmentalized. It is lined by a series of specialized epithelia that are regenerated by specific populations of stem cells. To maintain tissue homeostasis, the proliferative activity of stem and/or progenitor cells has to be carefully controlled and coordinated with regionally distinct programs of differentiation. Metaplasias and dysplasias, precancerous lesions that commonly occur in the human gastrointestinal tract, are often associated with the aberrant proliferation and differentiation of stem and/or progenitor cells. The increasingly sophisticated characterization of stem cells in the gastrointestinal tract of mammals and of the fruit fly Drosophila has provided important new insights into these processes and into the mechanisms that drive epithelial dysfunction. In this Review, we discuss recent advances in our understanding of the establishment, maintenance and regulation of diverse intestinal stem cell lineages in the gastrointestinal tract of Drosophila and mice. We also discuss the field's current understanding of the pathogenesis of epithelial dysfunctions.

Rho Kinase ROCK2 Mediates Acid-Induced NADPH Oxidase NOX5-S Expression in Human Esophageal Adenocarcinoma Cells

Mechanisms of the progression from Barrett’s esophagus (BE) to esophageal adenocarcinoma (EA) are not fully understood. We have shown that NOX5-S may be involved in this progression. However, how acid upregulates NOX5-S is not well known. We found that acid-induced increase in NOX5-S expression was significantly decreased by the Rho kinase (ROCK) inhibitor Y27632 in BE mucosal biopsies and FLO-1 EA cells. In addition, acid treatment significantly increased the Rho kinase activity in FLO-1 cells. The acid-induced increase in NOX5-S expression and H₂O₂ production was significantly decreased by knockdown of Rho kinase ROCK2, but not by knockdown of ROCK1. Conversely, the overexpression of the constitutively active ROCK2, but not the constitutively active ROCK1, significantly enhanced the NOX5-S expression and H₂O₂ production. Moreover, the acid-induced increase in Rho kinase activity and in NOX5-S mRNA expression was blocked by the removal of calcium in both FLO-1 and OE33 cells. The calcium ionophore A23187 significantly increased the Rho kinase activity and NOX5-S mRNA expression. We conclude that acid-induced increase in NOX5-S expression and H₂O₂ production may depend on the activation of ROCK2, but not ROCK1, in EA cells. The acid-induced activation of Rho kinase may be mediated by the intracellular calcium increase. It is possible that persistent acid reflux present in BE patients may increase the intracellular calcium, activate ROCK2 and thereby upregulate NOX5-S. High levels of reactive oxygen species derived from NOX5-S may cause DNA damage and thereby contribute to the progression from BE to EA.

The risk of oesophageal adenocarcinoma in a prospectively recruited Barrett's oesophagus cohort

BACKGROUND

Varying rates of oesophageal adenocarcinoma (OAC) complicating Barrett's oesophagus (BO) have been reported. Recent studies and meta-analyses suggest a lower incidence, questioning the value of endoscopic surveillance.

AIM

We aimed to retrospectively examine the rate of OAC, risk factors and causes of death in a prospectively recruited BO cohort.

METHODS

Data from patients with BO from a cohort from 1982-2007 were studied. Patients were subdivided into surveyed, failed to attend surveillance and unfit for surveillance. Standardised mortality ratios (SMR) were calculated for common causes of death. Cox proportional hazards models were used to determine which factors were associated with progression to OAC.

RESULTS

In total, 671 BO patients (61% male) were studied; 37 (76% male) were diagnosed with OAC. OAC incidence was 0.47% per annum and stable across three decades (1982-1991 0.56%, 1992-2001 0.46%, 2002-2012 0.41% (p = 0.8)). All-cause mortality was increased for the whole cohort (SMR 163(95% CI 145-183)). Mortality from OAC appeared higher in patients who failed to attend surveillance (SMR 3216(95% CI 1543-5916)) compared with surveyed (SMR 1753(95% CI 933-2998)) and those unfit for surveillance due to co-morbidity (SMR 440(95% CI 143-1025)). Multivariable analysis identified low-grade dysplasia (HR 4.4(95% CI 1.56-12.43), p = 0.005) and length of BO (HR 1.2(95% (1.1-1.3)), p < 0.001)) as associated with OAC.

CONCLUSIONS

Progression to OAC appeared stable over three decades at 0.47% per annum. Patients with BO had a modest increase in all-cause mortality and a large increase in OAC mortality, particularly if fit for surveillance. Low-grade dysplasia and the length of the BO segment were associated with developing OAC.

Targeting chemokine pathways in esophageal adenocarcinoma

Esophageal adenocarcinoma (EAC) is one of the fastest growing malignancies in the US and needs newer therapeutic and diagnostic strategies. Chronic inflammation plays a role in the pathogenesis of EAC and contributes to the dysplastic conversion of normal esophageal epithelium to Barrett's esophagus and frank adenocarcinoma. Chemokines play important roles in mediating inflammation and recent evidence implicates these ligands and their receptors in the development and spread of various tumors. We demonstrated that the chemokines IL8, CXCL1 and CXCL3 are significantly overexpressed during esophageal carcinogenesis and accompanied by amplification and demethylation of the chr4q21 gene locus. We also demonstrated that IL8 levels can be detected in serum of patients with EAC and can serve as potential biomarkers. We now demonstrate that inhibition of IL8 receptor, CXCR2, leads to decreased invasiveness of esophageal adenocarcinoma derived cells without affecting cellular proliferation. Taken together, these studies reveal the important roles that chemokines play in development of esophageal cancer and demonstrate that these pathways can serve as potential therapeutic targets.

Antidiabetic drug metformin inhibits esophageal adenocarcinoma cell proliferation in vitro and in vivo

Esophageal carcinoma is the eighth most common cancer worldwide and the sixth leading cause of cancer-related deaths, with one of the worst prognoses of any form of cancer. Treatment with the anti-diabetic drug metformin has been associated with reduced cancer incidence in patients with type 2 diabetes. This study therefore evaluated the effects of metformin on the proliferation, in vitro and in vivo, of human esophageal adenocarcinoma cells, as well as the microRNAs associated with the antitumor effects of metformin. Metformin inhibited the proliferation of the esophageal adenocarcinoma cell lines OE19, OE33, SK-GT4 and OACM 5.1C, blocking the G0 to G1 transition in the cell cycle. This was accompanied by strong reductions in G1 cyclins, especially cyclin D1, cyclin-dependent kinase (Cdk)4, and Cdk6, and decreases in retinoblastoma protein phosphorylation. In addition, metformin reduced the phosphorylation of epidermal growth factor receptor and insulin-like growth factor and insulin-like growth factor-1 receptor, as well as angiogenesis-related proteins, such as vascular endothelial growth factor, tissue inhibitor of metalloproteinases (TIMP)-1, and TIMP-2. Metformin also markedly altered microRNA expression. Treatment with metformin of athymic nude mice bearing xenograft tumors reduced tumor proliferation. These findings suggest that metformin may have clinical use in the treatment of esophageal adenocarcinoma.

Esophageal Helicobacter pylori colonization aggravates esophageal injury caused by reflux

AIM: To investigate esophageal Helicobacter pylori (H. pylori) colonization on esophageal injury caused by reflux and the related mechanisms.

METHODS: An esophagitis model, with acid and bile reflux, was surgically produced in male rats. The rats were randomly divided into either: (1) an esophagogastroduodenal anastomosis (EGDA) group; (2) an EGDA with H. pylori infection group; (3) a pseudo-operation with H. pylori infection group; or (4) a pseudo-operation group. All rats were kept for 36 wk. Based on the location of H. pylori colonization, the EGDA rats with H. pylori infection were subdivided into those with concomitant esophageal H. pylori colonization or those with only gastric H. pylori colonization. The esophageal injuries were evaluated grossly and microscopically. The expressions of CDX2 and MUC2 were determined by real-time polymerase chain reaction (RT-PCR) and immunohistochemistry. Ki-67 antigen expression was determined by immunohistochemistry. The mRNA levels of cyclin D1, c-Myc, Bax and Bcl-2 were determined by RT-PCR. Cell apoptosis was evaluated using the TdT-mediated dUTP nick-end labeling method.

RESULTS: Esophagitis, Barrett’s esophagus (BE), and esophageal adenocarcinoma (EAC) developed in rats that underwent EGDA. When comparing rats with EGDA and concomitant esophageal H. pylori colonization to EGDA-only rats, the severity of injury (87.9 ± 5.2 vs 77.2 ± 8.6, macroscopically, 92.5 ± 8.0 vs 83.8 ± 5.5, microscopically, both P < 0.05) and the incidences of BE (80.0% vs 33.3%, P = 0.055) and EAC (60.0% vs 11.1%, P < 0.05) were increased. These increases were associated with upregulation of CDX2 and MUC2 mRNA (10.1 ± 5.4 vs 3.0 ± 2.9, 8.4 ± 4.6 vs 2.0 ± 3.2, respectively, Ps < 0.01) and protein (8.1 ± 2.3 vs 3.3 ± 3.1, 7.3 ± 4.0 vs 1.8 ± 2.7, respectively, all P < 0.05). The expression of Ki-67 (8.9 ± 0.7 vs 6.0 ± 1.7, P < 0.01) and the presence of apoptotic cells (8.3 ± 1.1 vs 5.3 ± 1.7, P < 0.01) were also increased significantly in rats with EGDA and concomitant esophageal H. pylori colonization compared with rats with EGDA only. The mRNA levels of cyclin D1 (5.8 ± 1.9 vs 3.4 ± 1.3, P < 0.01), c-Myc (6.4 ± 1.7 vs 3.7 ± 1.2, P < 0.01), and Bax (8.6 ± 1.6 vs 5.1 ± 1.3, P < 0.01) were significantly increased, whereas the mRNA level of Bcl-2 (0.6 ± 0.3 vs 0.8 ± 0.3, P < 0.01) was significantly reduced in rats with EGDA and concomitant esophageal H. pylori colonization compared with rats with EGDA only.

CONCLUSION: Esophageal H. pylori colonization increases esophagitis severity, and facilitates the development of BE and EAC with the augmentation of cell proliferation and apoptosis in esophageal mucosa.

Modeling human gastrointestinal inflammatory diseases using microphysiological culture systems

Gastrointestinal illnesses are a significant health burden for the US population, with 40 million office visits each year for gastrointestinal complaints and nearly 250,000 deaths. Acute and chronic inflammations are a common element of many gastrointestinal diseases. Inflammatory processes may be initiated by a chemical injury (acid reflux in the esophagus), an infectious agent (Helicobacter pylori infection in the stomach), autoimmune processes (graft versus host disease after bone marrow transplantation), or idiopathic (as in the case of inflammatory bowel diseases). Inflammation in these settings can contribute to acute complaints (pain, bleeding, obstruction, and diarrhea) as well as chronic sequelae including strictures and cancer. Research into the pathophysiology of these conditions has been limited by the availability of primary human tissues or appropriate animal models that attempt to physiologically model the human disease. With the many recent advances in tissue engineering and primary human cell culture systems, it is conceivable that these approaches can be adapted to develop novel human ex vivo systems that incorporate many human cell types to recapitulate in vivo growth and differentiation in inflammatory microphysiological environments. Such an advance in technology would improve our understanding of human disease progression and enhance our ability to test for disease prevention strategies and novel therapeutics. We will review current models for the inflammatory and immunological aspects of Barrett's esophagus, acute graft versus host disease, and inflammatory bowel disease and explore recent advances in culture methodologies that make these novel microphysiological research systems possible.

The patterns of reflux can affect regression of non-dysplastic and low-grade dysplastic Barrett's esophagus after medical and surgical treatment: a prospective case-control study

BACKGROUND

To date, therapeutic guidelines and pattern of reflux for patients with no-dysplasia (ND) or low-grade dysplasia (LGD) Barrett's esophagus (BE) remain unclear. We aimed to analyze pattern of reflux and regression of ND- or LGD-BE after medical and surgical treatment.

METHODS

We studied a cohort of ND- and LGD-BE patients who underwent laparoscopic total fundoplication and a cohort of ND- and LGD-BE patients managed medically. Patients were matched for age, sex, and disease duration. After 1 year of follow-up at least, all patients underwent upper endoscopy with esophageal biopsies to evaluate any histological changes, as well as manometry and impedance-pH-metry to re-assess reflux patterns.

RESULTS

Thirty-seven patients (20 LGD, 17 ND) undergoing laparoscopic fundoplication were enrolled and compared with 25 patients (13 LGD, 12 ND) managed with proton pump inhibitors (PPI). Laparoscopic fundoplication resulted in a better control of both acidic and weakly acidic reflux (P < 0.001) and was associated with a higher probability of reversion for LGD (P < 0.01). Esophageal motility did not differ between surgically and medically treated patients.

CONCLUSIONS

In patients with ND- or LGD-BE, laparoscopic fundoplication seems to warrant a better control of all kinds of refluxate and it is associated with a higher likelihood of reversion of both LGD- and ND-BE, compared with PPI therapy.

Influence of Life Style Factors on Barrett's Oesophagus

Background. Since the incidence of adenocarcinoma of the oesophagus is rising, the prognosis is poor, and surveillance programs are expensive and mostly cost ineffective, there is a need to increase the knowledge of risk factors in Barrett's oesophagus and oesophageal cancer in order to be able to give attention to medical prevention and/or surveillance programs. Aim. To study if there is a correlation between the development of Barrett's oesophagus and GOR (gastro oesophageal reflux), family history of GOR, and life style factors, such as alcohol, smoking habits, and mental stress. Methods. Fifty-five consecutively selected patients with Barrett's oesophagus (BO) examined at Linköping University Hospital's Oesophageal Laboratory were matched by sex, age, and duration of reflux symptoms with 55 GOR patients without Barrett's oesophagus at the Oesophageal Laboratory. The medical charts in respective groups were examined for comparison of life style factors, mental stress, medication, duration of gastroesophageal acid reflux at 24 hr-pH-metry, and incidence of antireflux surgery and of adenocarcinoma of the oesophagus (ACO). Also, potential gender differences and diagnosis of ACO were studied. Results. Mean percentage reflux time on 24 hr-pH-metry was higher for the Barrett's oesophagus group, 18% for women and 17% for men compared to 4% for women and 4% for men in the control group (P < 0.05). Family history of GOR was more frequent in Barrett's oesophagus patients (62%) than in the control group (35%) (P < 0.05). Male patients with Barrett's oesophagus had medical therapy for their GOR symptoms to a higher extent (38%) than male controls (65%) (P < 0.05). No difference was found in the number of tobacco users or former tobacco users between Barrett's oesophagus patients and controls. Barrett's oesophagus patients had the same level of alcohol consumption and the same average BMI as the control subjects. Female patients with Barrett's oesophagus rated themselves as more mentally stressed (67%) than the female controls (38%) (P < 0.05). In the five-year medical chart follow-up, five of 55 patients developed adenocarcinoma among the Barrett's oesophagus patients, none in the control group. Conclusions. Long reflux time and family clustering of GOR seem to influence the development of Barrett's oesophagus. Smoking habits, alcohol consumption and BMI do not seem to have any impact on the development of Barrett's oesophagus.

Role of intracellular calcium and NADPH oxidase NOX5-S in acid-induced DNA damage in Barrett's cells and Barrett's esophageal adenocarcinoma cells

Mechanisms whereby acid reflux may accelerate the progression from Barrett's esophagus (BE) to esophageal adenocarcinoma (EA) are not fully understood. Acid and reactive oxygen species (ROS) have been reported to cause DNA damage in Barrett's cells. We have previously shown that NADPH oxidase NOX5-S is responsible for acid-induced H2O2 production in Barrett's cells and in EA cells. In this study we examined the role of intracellular calcium and NADPH oxidase NOX5-S in acid-induced DNA damage in a Barrett's EA cell line FLO and a Barrett's cell line CP-A. We found that pulsed acid treatment significantly increased tail moment in FLO and CP-A cells and histone H2AX phosphorylation in FLO cells. In addition, acid treatment significantly increased intracellular Ca(2+) in FLO cells, an increase that is blocked by Ca(2+)-free medium with EGTA and thapsigargin. Acid-induced increase in tail moment was significantly decreased by NADPH oxidase inhibitor diphenylene iodonium in FLO cells, and by blockade of intracellular Ca(2+) increase or knockdown of NOX5-S with NOX5 small-interfering RNA (siRNA) in FLO and CP-A cells. Acid-induced increase in histone H2AX phosphorylation was significantly decreased by NOX5 siRNA in FLO cells. Conversely, overexpression of NOX5-S significantly increased tail moment and histone H2AX phosphorylation in FLO cells. We conclude that pulsed acid treatment causes DNA damage via increase of intracellular calcium and activation of NOX5-S. It is possible that in BE acid reflux increases intracellular calcium, activates NOX5-S, and increases ROS production, which causes DNA damage, thereby contributing to the progression from BE to EA.

Consistency of a high-grade dysplasia diagnosis in Barrett's oesophagus: a Dutch nationwide cohort study

BACKGROUND

Consistency of high-grade dysplasia in Barrett's oesophagus is incompletely known and the clinical course may vary between patients.

AIMS

To evaluate the consistency of high-grade dysplasia diagnosis in a Dutch nationwide cohort and to identify predictors for (re-)detecting high-grade dysplasia or oesophageal adenocarcinoma when ≥ 1 follow-up evaluations after an initial high-grade dysplasia diagnosis were scored with a lower histological grade.

METHODS

In this retrospective cohort study, all patients diagnosed with high-grade dysplasia in Barrett's oesophagus between 1999 and 2008 in the Netherlands were selected using the nationwide histopathology registry. Multivariate analysis was performed to identify predictors for (re-)detecting high-grade dysplasia or oesophageal adenocarcinoma in patients with ≥ 1 follow-up evaluations scored with a lower grade.

RESULTS

In total, 512 high-grade dysplasia patients were included, of whom 53% had ≥ 1 follow-up evaluations scored with a lower grade. The (re-)detection risk was increased when follow-up was performed in a university hospital and when endoscopic/surgical resection was performed and decreased with an increasing number of follow-up evaluations scored with a lower grade.

CONCLUSION

High-grade dysplasia diagnosis was inconsistent in more than half of patients. (Endoscopic) resection in an expert centre is recommended to (re-)detect high-grade dysplasia or oesophageal adenocarcinoma when an endoscopic follow-up protocol with biopsies repeatedly shows a lower histological grade.

Family history of cancer and gastroesophageal disorders and risk of esophageal and gastric adenocarcinomas: a case-control study

Background

There is a paucity of data on familial risk of developing esophageal adenocarcinoma, gastric cardia adenocarcinoma and distal gastric adenocarcinoma from population-based studies.

Methods

A population-based case–control study of newly diagnosed gastroesophageal adenocarcinoma was conducted in Los Angeles County. This analysis included data of case-patients whom we were able to interview directly (147 patients with esophageal adenocarcinoma, 182 with gastric cardia adenocarcinoma, and 285 with distal gastric adenocarcinoma) and 1,309 control participants. Multivariate polytomous logistic regression was used to estimate odds ratios (ORs) and corresponding 95% confidence intervals (CIs) for the three cancer types.

Results

Risk of esophageal adenocarcinoma was positively associated with a family history of prostate cancer (OR = 2.84; 95% CI = 1.50-5.36) and a family history of hiatal hernia (OR = 2.04; 95% CI = 1.12-3.71). Risk of gastric cardia adenocarcinoma was strongly associated with a family history of esophageal cancer (OR = 5.18; 95% CI = 1.23-21.79) and a family history of hiatal hernia (OR = 2.31; 95% CI = 1.37-3.91). Risk of distal gastric adenocarcinoma was positively associated with a family history of gastric cancer (OR = 2.15; 95% CI = 1.18-3.91), particularly early-onset (before age 50) gastric cancer (OR = 2.82; 95% CI = 1.11-7.15).

Conclusions

This study provides evidence that family history of hiatal hernia is a risk factor for esophageal adenocarcinoma and gastric cardia adenocarcinoma and that cancer in specific sites is associated with risk of esophageal adenocarcinoma, gastric cardia adenocarcinoma, and distal gastric adenocarcinoma. It is important to determine the extent to which shared environmental and genetic factors explain these familial associations.

Mechanisms of obesity-induced gastrointestinal neoplasia

Obesity is among the fastest growing diseases worldwide; treatment is inadequate, and associated disorders, including gastrointestinal cancers, have high morbidity and mortality. An increased understanding of the mechanisms of obesity-induced carcinogenesis is required to develop methods to prevent or treat these cancers. In this report, we review the mechanisms of obesity-associated colorectal, esophageal, gastric, and pancreatic cancers and potential treatment strategies.

Meta-analysis of Barrett’s esophagus in China

AIM: To investigate the epidemiology and characteristics of Barrett’s esophagus (BE) in China and compare with cases in the west.

METHODS: Studies were retrieved from the China National Knowledge Infrastructure and PubMed databases using the terms “Barrett” and “Barrett AND China”, respectively, as well as published studies about BE in China from 2000 to 2011. The researchers reviewed the titles and abstracts of all search results to determine whether or not the literature was relevant to the current topic of this research. The references listed in the studies were also searched. Inclusion and exclusion criteria for the literature were appropriately established, and the data reported in the selected studies were analyzed. Finally, a meta-analysis was performed.

RESULTS: The current research included 3873 cases of BE from 69 studies. The endoscopic detection rate of BE in China was 1%. The ratio of male to female cases was 1.781 to 1, and the average age of BE patients was 49.07 ± 5.09 years. Island-type and short-segment BE were the most common endoscopic manifestations, accounting for 4.48% and 80.3%, respectively, of all cases studied. Cardiac-type BE was observed in 40.0% of the cases, representing the most common histological characteristic of the condition. Cancer incidence was 1.418 per 1000 person-years.

CONCLUSION: Average age of BE patients in China is lower than in Western countries. Endoscopic detection and cancer incidence were also lower in China.

Aberrant p53 protein expression is associated with an increased risk of neoplastic progression in patients with Barrett's oesophagus

OBJECTIVE

The value of surveillance for patients with Barrett's oesophagus (BO) is under discussion given the overall low incidence of neoplastic progression and lack of discriminative tests for risk stratification. Histological diagnosis of low-grade dysplasia (LGD) is the only accepted predictor for progression to date, but has a low predictive value. The aim of this study was therefore to evaluate the value of p53 immunohistochemistry for predicting neoplastic progression in patients with BO.

DESIGN

We conducted a case-control study within a prospective cohort of 720 patients with BO. Patients who developed high-grade dysplasia (HGD) or oesophageal adenocarcinoma (OAC) were classified as cases and patients without neoplastic progression were classified as controls. P53 protein expression was determined by immunohistochemistry in more than 12 000 biopsies from 635 patients and was scored independently by two expert pathologists who were blinded to long-term outcome.

RESULTS

During follow-up, 49 (8%) patients developed HGD or OAC. P53 overexpression was associated with an increased risk of neoplastic progression in patients with BO after adjusting for age, gender, Barrett length and oesophagitis (adjusted relative risks (RR(a)) 5.6; 95% CI 3.1 to 10.3), but the risk was even higher with loss of p53 expression (RR(a) 14.0; 95% CI 5.3 to 37.2). The positive predictive value for neoplastic progression increased from 15% with histological diagnosis of LGD to 33% with LGD and concurrent aberrant p53 expression.

CONCLUSIONS

Aberrant p53 protein expression is associated with an increased risk of neoplastic progression in patients with BO and appears to be a more powerful predictor of neoplastic progression than histological diagnosis of LGD.

Association between obesity and Barrett's esophagus in a Japanese population: a hospital-based, cross-sectional study

Background

The association between obesity and Barrett’s esophagus (BE) in the Japanese population remains unclear. The prevalence of BE and its associated risk factors was examined.

Methods

A cross-sectional study of 1581 consecutive individuals who underwent upper gastrointestinal endoscopy was conducted. The prevalence of endoscopically suspected BE (ESBE) was evaluated. Obesity was evaluated by body mass index (BMI, ≥ 25 kg/m²) and waist circumference (WC) (males, ≥ 85 cm; females, ≥ 90 cm). Because endoscopic diagnosis of ultra-short ESBE (<1 cm in extent) is difficult and highly unreliable, this type of ESBE was excluded from the study.

Results

In proton pump inhibitor (PPI) non-users, the prevalence of ESBE ≥ 1 cm was 5.6%. In univariate analysis, male sex and reflux esophagitis (RE) were significantly associated with BE, but BMI, WC, and reflux symptoms were not. In multivariate logistic regression analysis, only RE (odds ratio [OR] = 3.48, 95% confidence interval [CI] 1.89-6.41, p < 0.0001) was an independent risk factor for BE; obesity and the other factors were not. In contrast, RE (OR 5.67, p = 0.0004) and large WC (OR 5.09, p = 0.0005) were significant risk factors for ESBE ≥ 1 cm in PPI users. Only male sex, but not obesity or the other risk factors, was associated with an increased risk of RE in patients not taking PPIs.

Conclusions

RE, but not obesity, may have an independent association with the risk of ESBE in the Japanese population. Furthermore, obesity measures were not independent risks for RE. Interestingly, PPI-refractory RE and large WC were risk factors for ESBE ≥1 cm in patients taking PPIs.

Role of NADPH oxidase NOX5-S, NF-κB, and DNMT1 in acid-induced p16 hypermethylation in Barrett's cells

Inactivation of tumor suppressor genes via promoter hypermethylation may play an important role in the progression from Barrett's esophagus (BE) to esophageal adenocarcinoma (EA). We have previously shown that acid-induced p16 gene promoter hypermethylation may depend on activation of NADPH oxidase NOX5-S in BAR-T cells and OE33 EA cells. DNA methyltransferase 1 (DNMT1) is known to participate in maintaining established patterns of DNA methylation in dividing cells and may play an important role in the development of cancer. Therefore, we examined whether DNMT1 is involved in acid-induced p16 gene promoter hypermethylation in BAR-T cells. We found that the acid significantly increased p16 gene promoter methylation, decreased p16 mRNA, and increased cell proliferation, effects that may depend on activation of DNMT1 in BAR-T cells. DNMT1 is overexpressed in EA cells FLO and OE33 and EA tissues. Acid treatment upregulated DNMT1 mRNA expression and increased DNMT1 promoter activity. Acid-induced increases in DNMT1 mRNA expression and promoter activity were significantly decreased by knockdown of NOX5-S and NF-κB1 p50. Conversely, overexpression of NOX5-S, p50, or p65 significantly increased DNMT1 promoter activity. Knockdown of NOX5-S significantly decreased the acid-induced increase in luciferase activity in cells transfected with pNFκB-Luc. An NF-κB binding element GGGGTATCCC was identified in the DNMT1 gene promoter. We conclude that the acid-induced increase in p16 gene promoter methylation, downregulation of p16 mRNA, and increase in cell proliferation may depend on activation of DNMT1 in BAR-T cells. Acid-induced DNMT1 expression may depend on sequential activation of NOX5-S and NF-κB1 p50.

[Barrett's esophagus: analyses from human and experimental animal studies]

Whereas attention in the past has been focused on goblet cells as the primary marker for Barrett's esophagus (BE), the recent change in the definition now includes the non-goblet cell columnar cell-lined esophagus. In the present study the histological features of neoplasia of the lower esophagus and esophago-gastric junction in a German cohort were examined using immunohistochemical staining for MUC, CD10, intestinal and gastric type major tight junction proteins (claudins). Experimental studies using rat duodenogastric content reflux models have also been performed and data show that most neoplastic lesions of the esophageal glands in humans express gastric mucin phenotypes. Cardiac type mucosa was the main histological type in the surrounding mucosa of neoplastic lesions; however, most cardiac type mucosa has intestinal type tight junction proteins. BE with goblet cells has been reported to originate from stem cells located in the basal layer of esophageal squamous cell epithelium in previous models. However, the cardiac type mucosa seems to develop from the site of the stomach and not from the basal layer of esophageal squamous cell epithelium according to our model.

Value of α-methylacyl-CoA racemase immunochemistry for predicting neoplastic progression in Barrett's oesophagus

AIM

To investigate the value of α-methylacyl-CoA racemase (AMACR) immunohistochemistry for predicting neoplastic progression in Barrett's oesophagus (BO).

METHODS AND RESULTS

We conducted a case-control study within a prospective cohort of 720 BO patients. Patients who developed high-grade dysplasia or oesophageal adenocarcinoma were classified as cases, and patients without neoplastic progression as controls. AMACR expression was determined by immunohistochemistry in 12 127 biopsies from 635 patients, and was scored independently by two expert pathologists. Relative risks adjusted for age, gender, BO length and oesophagitis (RR(a)) were calculated in log-linear models. During a median follow-up of 6.6 years, 49 patients (8%) developed high-grade dysplasia or oesophageal adenocarcinoma. Although mild AMACR expression was associated with a trend towards an increased risk of neoplastic progression (RR(a) 1.6, 95% CI 0.9-3.1), the risk was especially elevated with strong AMACR expression (RR(a) 4.8, 95% CI 1.9-12.6). The positive predictive value of strong AMACR expression was slightly higher than that of low-grade dysplasia (22% versus 15%); the negative predictive value was slightly lower (91% versus 93%).

CONCLUSIONS

Strong AMACR expression is associated with an increased risk of neoplastic progression in BO. However, AMACR expression appears to be a less powerful predictor for neoplastic progression than low-grade dysplasia.

Interobserver agreement for the detection of Barrett's esophagus with optical frequency domain imaging

BACKGROUND

Optical frequency domain imaging (OFDI) is a second-generation form of optical coherence tomography (OCT) providing comprehensive cross-sectional views of the distal esophagus at a resolution of ~7 μm.

AIM

Using validated OCT criteria for squamous mucosa, gastric cardia mucosa, and Barrett's esophagus (BE), the objective of this study was to determine the inter- and intra-observer agreements by a large number of OFDI readers for differentiating these tissues.

METHODS

OFDI images were obtained from nine subjects undergoing screening and surveillance for BE. Sixty-four OFDI image regions of interest were randomly selected for review. A training set of 19 images was compiled distinguishing squamous mucosa from gastric cardia and BE using previously validated OCT criteria. The ten readers then interpreted images in a test set of 45 different images of squamous mucosa (n = 15), gastric cardia (n = 15), or BE (n = 15). Interobserver agreement differentiating the three tissue types and BE versus non-BE mucosa was determined using multi-rater Fleiss's κ value. The images were later randomized again and four readers repeated the test 3 weeks later to assess intraobserver reliability.

RESULTS

All ten readers showed excellent agreement for the differentiation of BE versus non-BE mucosa (κ = 0.811 p < 0.0001) and for differentiating BE versus gastric cardia versus squamous mucosa (κ = 0.866, p < 0.0001). For the four readers who repeated the test, the median intraobserver agreement (BE vs. non-BE) was high (κ = 0.975, IQR: 0.94, 1.0).

CONCLUSIONS

Trained readers have a high interobserver agreement for differentiating BE, squamous, and gastric cardia mucosa using OFDI.