Normal Squamous Esophagus Research Articles

Augmented CPT1A Expression Is Associated with Proliferation and Colony Formation during Barrett's Tumorigenesis.

Obesity is a known risk factor for the development of gastroesophageal reflux disease (GERD), Barrett’s Esophagus (BE) and the progression to esophageal adenocarcinoma. The mechanisms by which obesity contributes to GERD, BE and its progression are currently not well understood. Recently, changes in lipid metabolism especially in the context of a high fat diet have been linked to GERD and BE leading us to explore whether fatty acid oxidation plays a role in the disease progression from GERD to esophageal adenocarcinoma. To that end, we analyzed the expression of the rate-limiting enzyme, carnitine palmytoyltransferase 1A (CPT1A), in human tissues and cell lines representing different stages in the sequence from normal squamous esophagus to cancer. We determined uptake of palmitic acid, the most abundant fatty acid in human serum, with fluorescent dye-labeled lipids as well as functional consequences of stimulation with palmitic acid relevant to Barrett’s tumorigenesis, e.g., proliferation, characteristics of stemness and IL8 mediated inflammatory signaling. We further employed different mouse models including a genetic model of Barrett’s esophagus based on IL1β overexpression in the presence and absence of a high fat diet and deoxycholic acid to physiologically mimic gastrointestinal reflux in the mice. Together, our data demonstrate that CPT1A is upregulated in Barrett’s tumorigenesis and that experimental palmitic acid is delivered to mitochondria and associated with increased cell proliferation and stem cell marker expression.

Acid pH Increases SARS-CoV-2 Infection and the Risk of Death by COVID-19.

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) can infect a broad range of human tissues by using the host receptor angiotensin-converting enzyme 2 (ACE2). Individuals with comorbidities associated with severe COVID-19 display higher levels of ACE2 in the lungs compared to those without comorbidities, and conditions such as cell stress, elevated glucose levels and hypoxia may also increase the expression of ACE2. Here, we showed that patients with Barrett's esophagus (BE) have a higher expression of ACE2 in BE tissues compared to normal squamous esophagus, and that the lower pH associated with BE may drive this increase in expression. Human primary monocytes cultured in reduced pH displayed increased ACE2 expression and higher viral load upon SARS-CoV-2 infection. We also showed in two independent cohorts of 1,357 COVID-19 patients that previous use of proton pump inhibitors is associated with 2- to 3-fold higher risk of death compared to those not using the drugs. Our work suggests that pH has a great influence on SARS-CoV-2 Infection and COVID-19 severity.

Subtypes of Barrett’s oesophagus and oesophageal adenocarcinoma based on genome-wide methylation analysis

ObjectiveTo identify and characterise DNA methylation subtypes in oesophageal adenocarcinoma (EAC) and its precursor Barrett’s oesophagus (BE).DesignWe performed genome-wide DNA methylation profiling on samples of non-dysplastic BE from cancer-free patients...

Identification of a key role of widespread epigenetic drift in Barrett\u2019s esophagus and esophageal adenocarcinoma

BackgroundRecent studies have identified age-related changes in DNA methylation patterns in normal and cancer tissues in a process that is called epigenetic drift. However, the evolving patterns, functional consequences, and dynamics of epigenetic drift during carcinogenesis remain largely unexplored. Here we analyze the evolution of epigenetic drift patterns during progression from normal squamous esophagus tissue to Barrett’s esophagus (BE) to esophageal adenocarcinoma (EAC) using 173 tissue samples from 100 (nonfamilial) BE patients, along with publically available datasets including The Cancer Genome Atlas (TCGA).ResultsOur analysis reveals extensive methylomic drift between normal squamous esophagus and BE tissues in nonprogressed BE patients, with differential drift affecting 4024 (24%) of 16,984 normally hypomethylated cytosine-guanine dinucleotides (CpGs) occurring in CpG islands. The majority (63%) of islands that include drift CpGs are associated with gene promoter regions. Island CpGs that drift have stronger pairwise correlations than static islands, reflecting collective drift consistent with processive DNA methylation maintenance. Individual BE tissues are extremely heterogeneous in their distribution of methylomic drift and encompass unimodal low-drift to bimodal high-drift patterns, reflective of differences in BE tissue age. Further analysis of longitudinally collected biopsy samples from 20 BE patients confirm the time-dependent evolution of these drift patterns. Drift patterns in EAC are similar to those in BE, but frequently exhibit enhanced bimodality and advanced mode drift. To better understand the observed drift patterns, we developed a multicellular stochastic model at the CpG island level. Importantly, we find that nonlinear feedback in the model between mean island methylation and CpG methylation rates is able to explain the widely heterogeneous collective drift patterns. Using matched gene expression and DNA methylation data in EAC from TCGA and other publically available data, we also find that advanced methylomic drift is correlated with significant transcriptional repression of ~ 200 genes in important regulatory and developmental pathways, including several checkpoint and tumor suppressor-like genes.ConclusionsTaken together, our findings suggest that epigenetic drift evolution acts to significantly reduce the expression of developmental genes that may alter tissue characteristics and improve functional adaptation during BE to EAC progression.

Quantitative Shotgun Proteomics Unveils Candidate Novel Esophageal Adenocarcinoma (EAC)-specific Proteins

Esophageal cancer is the eighth most common cancer worldwide and the majority of patients have systemic disease at presentation. Esophageal adenocarcinoma (OAC), the predominant subtype in western countries, is largely resistant to current chemotherapy regimens. Selective markers are needed to enhance clinical staging and to allow targeted therapies yet there are minimal proteomic data on this cancer type. After histological review, lysates from OAC and matched normal esophageal and gastric samples from seven patients were subjected to LC MS/MS after tandem mass tag labeling and OFFGEL fractionation. Patient matched samples of OAC, normal esophagus, normal stomach, lymph node metastases and uninvolved lymph nodes were used from an additional 115 patients for verification of expression by immunohistochemistry (IHC).Over six thousand proteins were identified and quantified across samples. Quantitative reproducibility was excellent between technical replicates and a moderate correlation was seen across samples with the same histology. The quantitative accuracy was verified across the dynamic range for seven proteins by immunohistochemistry (IHC) on the originating tissues. Multiple novel tumor-specific candidates are proposed and EPCAM was verified by IHC.This shotgun proteomic study of OAC used a comparative quantitative approach to reveal proteins highly expressed in specific tissue types. Novel tumor-specific proteins are proposed and EPCAM was demonstrated to be specifically overexpressed in primary tumors and lymph node metastases compared with surrounding normal tissues. This candidate and others proposed in this study could be developed as tumor-specific targets for novel clinical staging and therapeutic approaches.

Extensive telomere erosion is consistent with localised clonal expansions in Barrett's metaplasia.

Barrett’s oesophagus is a premalignant metaplastic condition that predisposes patients to the development of oesophageal adenocarcinoma. However, only a minor fraction of Barrett’s oesophagus patients progress to adenocarcinoma and it is thus essential to determine bio-molecular markers that can predict the progression of this condition. Telomere dysfunction is considered to drive clonal evolution in several tumour types and telomere length analysis provides clinically relevant prognostic and predictive information. The aim of this work was to use high-resolution telomere analysis to examine telomere dynamics in Barrett’s oesophagus. Telomere length analysis of XpYp, 17p, 11q and 9p, chromosome arms that contain key cancer related genes that are known to be subjected to copy number changes in Barrett’s metaplasia, revealed similar profiles at each chromosome end, indicating that no one specific telomere is likely to suffer preferential telomere erosion. Analysis of patient matched tissues (233 samples from 32 patients) sampled from normal squamous oesophagus, Z-line, and 2 cm intervals within Barrett’s metaplasia, plus oesophago-gastric junction, gastric body and antrum, revealed extensive telomere erosion in Barrett’s metaplasia to within the length ranges at which telomere fusion is detected in other tumour types. Telomere erosion was not uniform, with distinct zones displaying more extensive erosion and more homogenous telomere length profiles. These data are consistent with an extensive proliferative history of cells within Barrett’s metaplasia and are indicative of localised clonal growth. The extent of telomere erosion highlights the potential of telomere dysfunction to drive genome instability and clonal evolution in Barrett’s metaplasia.

Association Between Germline Mutation in VSIG10L and Familial Barrett Neoplasia.

Esophageal adenocarcinoma and its precursor lesion Barrett esophagus have seen a dramatic increase in incidence over the past 4 decades yet marked genetic heterogeneity of this disease has precluded advances in understanding its pathogenesis and improving treatment. To identify novel disease susceptibility variants in a familial syndrome of esophageal adenocarcinoma and Barrett esophagus, termed familial Barrett esophagus, by using high-throughput sequencing in affected individuals from a large, multigenerational family. We performed whole exome sequencing (WES) from peripheral lymphocyte DNA on 4 distant relatives from our multiplex, multigenerational familial Barrett esophagus family to identify candidate disease susceptibility variants. Gene variants were filtered, verified, and segregation analysis performed to identify a single candidate variant. Gene expression analysis was done with both quantitative real-time polymerase chain reaction and in situ RNA hybridization. A 3-dimensional organotypic cell culture model of esophageal maturation was utilized to determine the phenotypic effects of our gene variant. We used electron microscopy on esophageal mucosa from an affected family member carrying the gene variant to assess ultrastructural changes. Identification of a novel, germline disease susceptibility variant in a previously uncharacterized gene. A multiplex, multigenerational family with 14 members affected (3 members with esophageal adenocarcinoma and 11 with Barrett esophagus) was identified, and whole-exome sequencing identified a germline mutation (S631G) at a highly conserved serine residue in the uncharacterized gene VSIG10L that segregated in affected members. Transfection of S631G variant into a 3-dimensional organotypic culture model of normal esophageal squamous cells dramatically inhibited epithelial maturation compared with the wild-type. VSIG10L exhibited high expression in normal squamous esophagus with marked loss of expression in Barrett-associated lesions. Electron microscopy of squamous esophageal mucosa harboring the S631G variant revealed dilated intercellular spaces and reduced desmosomes. This study presents VSIG10L as a candidate familial Barrett esophagus susceptibility gene, with a putative role in maintaining normal esophageal homeostasis. Further research assessing VSIG10L function may reveal pathways important for esophageal maturation and the pathogenesis of Barrett esophagus and esophageal adenocarcinoma.

Abstract 3815: Cyclin-dependent kinase 9: a potential therapeutic target for esophageal adenocarcinoma

Abstract Objective: Major limitation of successful implementation of targeted therapy in esophageal adenocarcinoma (EAC) is low frequency of target specific biomarker alteration and intratumoral heterogeneity. Cyclin dependent kinase 9 (CDK9) is a ubiquitous serine threonine kinase whoseinhibition has been used as a therapeutic option in other solid tumors. However, critical in vitro and in vivo information about the efficacy and mechanism of CDK9 inhibition in EAC is lacking and needs to be generated before a clinical trial is proposed. Design: We assessed the CDK9 protein expression in EAC cell lines and in patient tissue samples of Barrett's esophagus and EAC. Subsequently, we studied effects of genetic downregulation (shCDK9) in SKGT4 and chemical inhibition of CDK9 by CDK9 inhibitor II, a specific, potent competitive inhibitor of CDK9 (Santa Cruz Biotechnology, CA) on proliferation, apoptosis, and cell cycle of SKGT4, FLO-1 and OE33. In vivo effects of shCDK9 and CDK9 inhibitor II was analyzed in xenografts experiments performed on nude mice after injection of FLO-1 or shCDK9-SKGT 4 and control cells in right flank or abdomen. We also assessed the effects of shCDK9 and CDK9 inhibitor II on expression of MCL-1 and phosphorylation of RNA polymerase II in EAC cells. Results: Higher expression of CDK9 was observed in all EAC cell lines and in tumor samples of patients with EAC as compared to normal squamous epithelium and Barrett's Esophagus. shCDK9 in SKGT4 cells induced significant reduction in proliferation, increase in apoptosis and G1 arrest as compared to control cells in vitro. In vivo experiment with SKGT4-shCDK9 demonstrated no tumor growth in 4 of 10 mice and tumor volume was significantly smaller in SKGT4-shCDK9 as compared to control SKGT4 cells (72.89 ± 12.88 mm3 v.270 ± 64.07 mm3, p< 0.01) in other mice. Treatment with CDK9 inhibitor II demonstrated dose dependent reduction in proliferation, increased apoptosis and G1 arrest in all three cell lines in vitro and more than 50% reduction in tumor volume in xenografts as compared to control. CDK9 inhibitor II reduced RNA Pol II phosphorylation and expression of MCL-l and up-regulation of MCL-1 expression induced resistance to CDK9 inhibitor II in all three EAC cell lines.. Conclusions: CDK9 inhibition has strong anti-EAC properties in vitro and in vivo. These properties along with strong diffuse expression of CDK9 in human EAC support further exploration of CDK9 as a potential therapeutic target for EAC. Citation Format: Zhimin Tong, Devkumar Chatterjee, Defeng Deng, Omkara Veeranki, Alicia Mejia, Jaime Rodriguez, Jaffer Ajani, Wayne Hofstetter, Steven Lin, Sushovan Guha, Scott Kopetz, Sunil Krishnan, Dipen Maru. Cyclin-dependent kinase 9: a potential therapeutic target for esophageal adenocarcinoma. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 3815.

PWE-069 Sampling Oesophageal Microbial Communities in Barrett’s Oesophagus Using Minimally Invasive and Endoscopic Methods

Introduction Minimally invasive methods for sampling the oesophageal microbiota may be clinically useful for detection and risk stratification of patients with Barrett’s oesophagus. The Cytosponge is a non-endoscopic device that samples epithelial cells and bacteria along the length of the oesophagus. This study aimed to determine the utility of the Cytosponge for sampling the oesophageal microbiota, and to assess whether the device could detect altered microbiota in Barrett’s oesophagus. Methods 251 samples from 67 patients and relevant negative controls underwent 16 S rRNA gene sequencing (in duplicate) on the Illumina MiSeq platform. A subset of Cytosponge samples (N = 31) was compared with matched fresh frozen endoscopic biopsies (N = 31), endoscopic brushings (N = 31) and throat swabs (N = 13). The microbial DNA yield for the different oesophageal sample types was analysed using quantitative PCR for overall bacterial abundance. 16 S rRNA gene data was further interrogated from patients representing the Barrett’s progression sequence, including normal squamous oesophagus (N = 20), Barrett’s oesophagus (N = 24), and high grade dysplasia (N = 23). Results 16 S rRNA gene data showed the majority of genera overlapped between Cytosponge samples and endoscopic brushes and biopsies (84%, cut-off >0.0001% abundance; 100%, cut-off >0.1% abundance), but the Cytosponge samples were enriched for genera known to be prevalent in the stomach and oral cavity such as Campylobacter and Fusobacterium, respectively (q Conclusion The Cytosponge was capable of sampling the microbiota in the oesophagus and proximal stomach, and detected decreased diversity in patients with high grade dysplasia compared to normal squamous oesophagus. Disclosure of Interest D. R. Fels Elliott: None Declared, A. Walker: None Declared, M. O’Donovan: None Declared, J. Parkhill: None Declared, R. Fitzgerald Grant/research support from: RCF developed the Cytosponge™ technology with MRC-Technology, which provided devices for research. The Cytosponge™ has recently been licensed to Covidien, and RCF has no direct financial relationship with Covidien.

An immunofluorescent method for characterization of Barrett's esophagus cells.

Esophageal adenocarcinoma (EAC) has an overall survival rate of less than 17% and incidence of EAC has risen dramatically over the past two decades. One of the primary risk factors of EAC is Barrett's esophagus (BE), a metaplastic change of the normal squamous esophagus in response to chronic heartburn. Despite the well-established connection between EAC and BE, interrogation of the molecular events, particularly altered signaling pathways involving progression of BE to EAC, are poorly understood. Much of this is due to the lack of suitable in vitro models available to study these diseases. Recently, immortalized BE cell lines have become commercially available allowing for in vitro studies of BE. Here, we present a method for immunofluorescent staining of immortalized BE cell lines, allowing in vitro characterization of cell signaling and structure after exposure to therapeutic compounds. Application of these techniques will help develop insight into the mechanisms involved in BE to EAC progression and provide potential avenues for treatment and prevention of EAC.

OC-016 The Toll-like Receptor Pathway Is Recurrently Mutated In Oesophageal Adenocarcinoma

IntroductionThe interaction between the oesophageal microbiota and the inflammatory microenvironment in Barrett’s carcinogenesis is poorly understood. One of the mechanisms by which microbiota may induce chronic inflammation is by triggering...

Sa1843 The Toll-Like Receptor Pathway Is Recurrently Mutated in Esophageal Adenocarcinoma

Introduction The interaction between the oesophageal microbiota and the inflammatory microenvironment in Barrett’s carcinogenesis is poorly understood. One of the mechanisms by which microbiota may induce chronic inflammation is by triggering Toll-like receptor (TLR) signalling and activation of nuclear factor kappa B. We aimed to utilise whole genome sequencing (WGS) data to investigate TLR mutations and expression in oesophageal adenocarcinoma (OAC), with a focus on TLR9. Methods We interrogated the mutational profiles of 66 OAC samples, with matched germline references from each case, which had undergone WGS as part of the oesophageal ICGC study. All mutations were verified using PCR and Sanger sequencing. To further explore TLR9 expression along the Barrett’s progression sequence, we performed TLR9 immunohistochemistry on tissue microarray samples including normal squamous oesophagus (N=16), duodenum (N=14), non-dysplastic Barrett’s (N=53), low-grade dysplasia (N=13), high-grade dysplasia (N=25) and OAC (N=338). Within the large cohort of OAC samples we binarised the intensity scores (0–1 and 2–3) and examined whether there were any significant differences in relation to clinicopathologic variables (TNM stage, histological grade, lymphovascular invasion, survival). Results We identified missense mutations in TLR pathway genes in 8/66 (12.1%) of OAC samples, including TLR1 (1.5%), TLR4 (3%), TLR7 (1.5%), TLR9 (3%), MYD88 (1.5%), and TRAF6 (1.5%). TLR9 protein was expressed more highly in Barrett’s and OAC than normal oesophageal squamous tissue (p Conclusion TLR pathway genes appear to be recurrently mutated in OAC, which given the mutational context and heterogeneity of disease 1 could represent significant involvement of the TLR signalling pathway in Barrett’s carcinogenesis. Reference 1 Dulak AM, et al . Exome and whole-genome sequencing of esophageal adenocarcinoma identifies recurrent driver events and mutational complexity. Nat Genet . 2013 May;45(5):478-86 Disclosure of Interest None Declared.

In vivomolecular imaging of HER2 expression in a rat model of Barrett's esophagus adenocarcinoma

Human epidermal growth factor receptor 2 (HER2) is involved in the malignant progression of several human cancers, including esophageal adenocarcinoma (EAC). The purpose of this study was to evaluate HER2 overexpression and to explore the feasibility of confocal laser endomicroscopy for in vivo molecular imaging of HER2 status in an animal model of Barrett's-related EAC. Rats underwent esophagojejunostomy with gastric preservation. At 30 weeks post-surgery, the esophagus of 46 rats was studied; endoscopic and histological findings were correlated with HER2 immunofluorescence on excised biopsies and gross specimens. At this age, 23/46 rats developed Barrett's esophagus (BE), and 6/46 had cancer (four EAC and two squamous cell carcinomas). A significant overexpression of HER2 was observed in esophageal adenocarcinoma compared with normal squamous esophagus (9.4-fold) and BE (6.0-fold). AKT and its phosphorylated form were also overexpressed in cancer areas. Molecular imaging was performed at 80 weeks post-surgery in four rats after tail injection of fluorescent-labeled anti-HER2 antibody. At this age, 3/4 rats developed advance adenocarcinoma and showed in vivo overexpression of HER2 by molecular confocal laser endomicroscopy with heterogeneous distribution within cancer; no HER2 signal was observed in normal or Barrett's tissues. Therefore, HER2 overexpression is a typical feature of the surgical induced model of EAC that can be easily quantified in vivo using an innovative mini-invasive approach including confocal endomicroscopy; this approach may avoid limits of histological evaluation of HER2 status on 'blinded' biopsies.

The human squamous oesophagus has widespread capacity for clonal expansion from cells at diverse stages of differentiation

ObjectiveKnowledge of the cellular mechanisms involved in homeostasis of human squamous oesophagus in the steady state and following chronic injury is limited. We aimed to better understand these mechanisms by...

Recent advances in oesophageal diseases.

Recent advances in oesophageal diseases.

Toll-like receptor 4 activation in Barrett’s esophagus results in a strong increase in COX-2 expression

Barrett's esophagus (BE) is known to progress to esophageal adenocarcinoma in a setting of chronic inflammation. Toll-like receptor (TLR) 4 has been linked to inflammation-associated carcinogenesis. We aimed to determine the expression and functional activity of TLR4 in the esophagus and whether TLR4 activation in BE could promote carcinogenesis by inducing COX-2 expression. TLR4 expression in esophageal adenocarcinoma, BE, duodenum, reflux esophagitis and normal squamous esophagus biopsies was assessed using real-time PCR and validated by in situ hybridization and immunohistochemistry. Ex vivo cultures of BE, duodenum and normal squamous esophagus biopsies and a BE cell line (BAR-T) were stimulated with the TLR4 agonist lipopolysaccharide (LPS). To evaluate the effect of TLR4 activation, NF-κB activation, IL8 secretion and expression and COX-2 expression were determined. TLR4 expression was significantly increased in esophageal adenocarcinoma, BE, duodenum and reflux esophagitis compared to normal squamous esophagus. LPS stimulation resulted in NF-κB activation and a dose-dependent increase of IL8 secretion and mRNA expression. The induction of IL8 was more evident in BE compared to normal squamous esophagus. Upon LPS stimulation, COX-2 expression increased significantly in ex vivo cultured BE biopsies, which was observed in both epithelium and lamina propria cells. However, no effect was found in duodenum and normal squamous esophagus biopsies. TLR4 activation in BE results in a strong increase in COX-2 and may contribute to malignant transformation.

MicroRNA Expression Differentiates Squamous Epithelium from Barrett’s Esophagus and Esophageal Cancer

Current strategies fail to identify most patients with esophageal adenocarcinoma (EAC) before the disease becomes advanced and incurable. Given the dismal prognosis associated with EAC, improvements in detection of early-stage esophageal neoplasia are needed. We sought to assess whether differential expression of microRNAs could discriminate between squamous epithelium, Barrett's esophagus (BE), and EAC. We analyzed microRNA expression in a discovery cohort of human endoscopic biopsy samples from 36 patients representing normal squamous esophagus (n = 11), BE (n = 14), and high-grade dysplasia/EAC (n = 11). RNA was assessed using microarrays representing 847 human microRNAs followed by quantitative real-time polymerase chain reaction (qRT-PCR) verification of nine microRNAs. In a second cohort (n = 18), qRT-PCR validation of five miRNAs was performed. Expression of 59 microRNAs associated with BE/EAC in the literature was assessed in our training cohort. Known esophageal cell lines were used to compare miRNA expression to tissue miRNAs. After controlling for multiple comparisons, we found 34 miRNAs differentially expressed between squamous esophagus and BE/EAC by microarray analysis. However, miRNA expression did not reliably differentiate non-dysplastic BE from EAC. In the validation cohort, all five microRNAs selected for qRT-PCR validation differentiated between squamous samples and BE/EAC. Microarray results supported 14 of the previously reported microRNAs associated with BE/EAC in the literature. Cell lines did not generally reflect miRNA expression found in vivo. These data indicate that miRNAs differ between squamous esophageal epithelium and BE/EAC, but do not distinguish between BE and EAC. We suggest prospective evaluation of miRNAs in patients at high risk for EAC.

Nuclear Nano-architecture Markers of Gastric Cardia and Upper Squamous Esophagus Detect Esophageal Cancer “Field Effect”

Background: Barrett's esophagus (BE) affects up to 12 million Americans and confers an increased risk for development of esophageal adenocarcinoma (EAC). EAC is often fatal unless detected early. Given the high prevalence, high cost of surveillance and relatively low risk of most affected individuals, identification of high-risk patients for additional scrutiny, regular surveillance, or ablative therapy is crucial. The exploration of “field effect” by probing uninvolved esophageal mucosa to predict the risk of EAC has the potential as an improved surveillance and prevention strategy. In this study, we evaluate the ability of nuclear nano-architecture markers from normal squamous esophagus and gastric cardia to detect the “field effect” of esophageal dysplasia and EAC, and their response to endoscopic therapy.Methods: Patients with normal esophagus, gastroesophageal reflux, BE and EAC were eligible for enrollment. We performed endoscopic cytology brushings of the gastric cardia, ~1-2 cm below the gastroesophageal junction, and of the normal squamous esophageal mucosa at ~20 cm from the incisors and standard cytology slides were made using Thinprep method. Optical analysis was performed on the cell nuclei of cytologically normal-appearing epithelial cells.Results: The study cohort consisted of 128 patients. The nuclear nano-architecture markers detected the presence of esophageal dysplasia and EAC with statistical significance. The field effect does not exhibit a spatial dependence. These markers reverted toward normal in response to endoscopic therapy.Conclusions: Optical analysis of gastric cardia and upper squamous esophagus represents a potentially viable method to improve risk stratification and ease of surveillance of patients with Barrett's esophagus and to monitor the efficacy of ablative therapy.

Assessment of a custom-built Raman spectroscopic probe for diagnosis of early oesophageal neoplasia

We evaluate the potential of a custom-built fiber-optic Raman probe, suitable for in vivo use, to differentiate between benign, metaplastic (Barrett's oesophagus), and neoplastic (dysplastic and malignant) oesophageal tissue ex vivo on short timescales. We measured 337 Raman spectra (λ(ex)=830 nm; P(ex)=60 mW; t=1 s) using a confocal probe from fresh (298) and snap-frozen (39) oesophageal tissue collected during surgery or endoscopy from 28 patients. Spectra were correlated with histopathology and used to construct a multivariate classification model which was tested using leave one tissue site out cross-validation in order to evaluate the diagnostic accuracy of the probe system. The Raman probe system was able to differentiate, when tested with leave one site out cross-validation, between normal squamous oesophagus, Barrett's oesophagus and neoplasia with sensitivities of (838% to 6%) and specificities of (89% to 99%). Analysis of a two group model to differentiate Barrett's oesophagus and neoplasia demonstrated a sensitivity of 88% and a specificity of 87% for classification of neoplastic disease. This fiber-optic Raman system can provide rapid, objective, and accurate diagnosis of oesophageal pathology ex vivo. The confocal design of this probe enables superficial mucosal abnormalities (metaplasia and dysplasia) to be classified in clinically applicable timescales paving the way for an in vivo trial.

PWE-026 Infrared spectroscopy acurately detects Barrett's mucosa biopsy specimens ex vivo

IntroductionOesophageal cancer (OAC) arises in Barrettt's oesopahgus (BE) and carries a poor prognosis. Early mucosal neoplasia arising in BE can be treated successfully with minimally invasive endotherapy. Fourier transform infrared...