MUC2 is a highly specific marker of goblet cell metaplasia in the distal esophagus and gastroesophageal junction

The Aberrant Expression of Biomarkers and Risk Prediction for Neoplastic Changes in Barrett's Esophagus-Dysplasia

Background: Barrett's esophagus (BE) is a pre-neoplastic condition associated with an increased risk of esophageal adenocarcinoma (EAC). The accurate diagnosis of BE and grading of dysplasia can help to optimize the management of patients with BE. However, BE may be missed and the accurate grading of dysplasia based on a routine histology has a considerable intra- and interobserver variability. Thus, well-defined biomarker testing remains indispensable. The aim of our study was to identify routinely applicable and relatively specific biomarkers for an accurate diagnosis of BE, as well as determining biomarkers to predict the risk of progression in BE-dysplasia. Methods: Retrospectively, we performed immunohistochemistry to test mucin 2(MUC2), trefoil factor 3 (TFF3), p53, p16, cyclin D1, Ki-67, beta-catenin, and minichromosome maintenance (MCM2) in biopsies. Prospectively, to identify chromosomal alterations, we conducted fluorescent in situ hybridization testing on fresh brush samples collected at the time of endoscopy surveillance. Results: We discovered that MUC2 and TFF3 are specific markers for the diagnosis of BE. Aberrant expression, including the loss and strong overexpression of p53, Ki-67, p16, beta-catenin, cyclin D1, and MCM2, was significantly associated with low-grade dysplasia (LGD), high-grade dysplasia (HGD), and EAC histology, with a relatively high risk of neoplastic changes. Furthermore, the aberrant expressions of p53 and p16 in BE-indefinite dysplasia (IND) progressor cohorts predicted the risk of progression. Conclusions: Assessing the biomarkers would be a suitable adjunct to accurate BE histology diagnoses and improve the accuracy of BE-dysplasia grading, thus reducing interobserver variability, particularly of LGD and risk prediction.

Intestinal metaplasia in follow-up endoscopies among Asian patients with short-segment Barrett's esophagus: Regression, sampling error, and associated factors

BACKGROUND

The percentage of and factors associated with the regression of Barrett's esophagus (BE) or its characteristic intestinal metaplasia (IM) remain unclear, and conflicting results have been reported because of diverse regression and sampling error definitions. Thus, we investigated the rates of IM regression, sampling error, and associated factors.

METHODS

Forty-two patients with proven short-segment BE with IM who underwent two follow-up endoscopies with biopsies of Barrett's mucosa were retrospectively analyzed. Additional Alcian blue and MUC2 staining were done on the biopsy specimens without IM in hematoxylin-eosin staining. Only patients with negative hematoxylin-eosin, Alcian blue, and MUC2 staining for IM in both follow-up endoscopies were considered to have true regression. When all three stains were negative for IM in the first, but positive in the second follow-up endoscopy, we considered IM persisting and declared sampling error.

RESULTS

Among the 18 patients without IM at the first follow-up endoscopy, only five (11.9%) were judged to have true regression. Prolonged proton-pump inhibitor use was significantly associated with regression. Limited experience of the endoscopist, and insufficient biopsy number were significantly related to sampling error. Receiver operating characteristic (ROC) curve analysis showed the best cut-off value of the biopsy number/maximal-length (cm) ratio to predict sampling error was 2.25.

CONCLUSION

In our patients with short-segment BE, 11.9% experienced regression of IM. Prolonged proton-pump inhibitors treatment was associated with regression. An insufficient biopsy number was related to a missed IM, which may be eliminated by maintaining biopsy number/maximal-length (cm) ratio ≥2.25.

Post-Translational Modifications in Tumor-Associated Antigens as a Platform for Novel Immuno-Oncology Therapies

Post-translational modifications (PTMs) are generated by adding small chemical groups to amino acid residues after the translation of proteins. Many PTMs have been reported to correlate with tumor progression, growth, and survival by modifying the normal functions of the protein in tumor cells. PTMs can also elicit humoral and cellular immune responses, making them attractive targets for cancer immunotherapy. This review will discuss how the acetylation, citrullination, and phosphorylation of proteins expressed by tumor cells render the corresponding tumor-associated antigen more antigenic and affect the immune response in multiple cancers. In addition, the role of glycosylated protein mucins in anti-cancer immunotherapy will be considered. Mucin peptides in combination with stimulating adjuvants have, in fact, been utilized to produce anti-tumor antibodies and vaccines. Finally, we will also outline the results of the clinical trial exploiting glycosylated-MUC1 as a vaccine in different cancers. Overall, PTMs in TAAs could be considered in future therapies to result in lasting anti-tumor responses.

Microbial and host factors contribute to bloodstream infection in a pediatric acute lymphocytic leukemia mouse model

Background

Hematological malignancies are the most common cancers in the pediatric population, and T-cell acute lymphocytic leukemia (T-ALL) is the most common hematological malignancy in children. Bloodstream infection (BSI) is a commonly occurring complication in leukemia due to underlying conditions and therapy-induced neutropenia. Several studies identified the gut microbiome as a major source of BSI due to bacterial translocation. This study aimed to investigate changes in the intestinal and fecal microbiome, and their roles in the pathophysiology of BSI in a pediatric T-ALL mouse model using high-throughput shotgun metagenomics sequencing, and metabolomics.

Results

Our results show that BSI in ALL is characterized by an increase of a mucin degrading bacterium (Akkermansia muciniphila) and a decrease of butyrate producer Clostridia spp., along with a decrease in short-chain fatty acid (SCFA) concentrations and differential expression of tight junction proteins in the small intestine. Functional analysis of the small intestinal microbiome indicated a reduced capability of SCFA synthesis, while SCFA supplementation ameliorated the development of BSI in ALL.

Conclusions

Our data indicates that changes in the microbiome, and the resulting changes in levels of SCFAs contribute significantly to the pathogenesis of bloodstream infection in ALL. Our study provides tailored preventive or therapeutic approaches to reduce BSI-associated mortality in ALL.

Barrett's esophagus: The pathomorphological and molecular genetic keystones of neoplastic progression

Barrett's esophagus is a widespread chronically progressing disease of heterogeneous nature. A life threatening complication of this condition is neoplastic transformation, which is often overlooked due to lack of standardized approaches in diagnosis, preventative measures and treatment. In this essay, we aim to stratify existing data to show specific associations between neoplastic transformation and the underlying processes which predate cancerous transition. We discuss pathomorphological, genetic, epigenetic, molecular and immunohistochemical methods related to neoplasia detection on the basis of Barrett's esophagus. Our review sheds light on pathways of such neoplastic progression in the distal esophagus, providing valuable insight into progression assessment, preventative targets and treatment modalities. Our results suggest that molecular, genetic and epigenetic alterations in the esophagus arise earlier than cancerous transformation, meaning the discussed targets can help form preventative strategies in at-risk patient groups.

Gastro-esophageal reflux disease and Barrett's esophagus: an overview with an histologic diagnostic approach

The first part of this overview on non-neoplastic esophagus is focused on gastro-esophageal reflux disease (GERD) and Barrett’s esophagus. In the last 20 years much has changed in histological approach to biopsies of patients with gastro-esophageal reflux disease. In particular, elementary histologic lesions have been well defined and modality of evaluation and grade are detailed, their sensitivity and specificity has been evaluated and their use has been validated by several authors. Also if there is not a clinical indication to perform biopsies in patient with GERD, the diagnosis of microscopic esophagitis, when biopsies are provided, can be performed by following simple rules for evaluation which allow pathologists to make the diagnosis with confidence. On the other hand, biopsies are required for the diagnosis of Barrett’s esophagus. This diagnosis is the synthesis of endoscopic picture (which has to be provided with the proper description on extent and with adequate biopsies number) and histologic pattern. The current guidelines and expert opinions for the correct management of these diagnosis are detailed.

Barrett's Esophagus and Intestinal Metaplasia

Intestinal metaplasia refers to the replacement of the differentiated and mature normal mucosal epithelium outside the intestinal tract by the intestinal epithelium. This paper briefly describes the etiology and clinical significance of intestinal metaplasia in Barrett’s esophagus. This article summarizes the impact of intestinal metaplasia on the diagnosis, monitoring, and treatment of Barrett’s esophagus according to different guidelines. We also briefly explore the basis for the endoscopic diagnosis of intestinal metaplasia in Barrett’s esophagus. The identification techniques of goblet cells in Barrett’s esophagus are also elucidated by some scholars. Additionally, we further elaborate on the current treatment methods related to Barrett’s esophagus.

Puerarin prevents high-fat diet-induced obesity by enriching Akkermansia muciniphila in the gut microbiota of mice

Growing evidence indicates that the gut microbiota plays a significant role in the pathophysiological processes of obesity and its related metabolic symptoms in the host. Puerarin, an active ingredient in the root of Pueraria lobate has been suggested to have a potent anti-obesity effect. Herein, we tested whether this effect of puerarin is associated with changes in the gut microbiota. In addition to reducing body weight, inflammation, and insulin resistance, puerarin administration significantly altered the composition of the gut microbiota. Notably, puerarin treatment greatly increased the abundance of Akkermansia muciniphila, a mucin-degrading bacterium known to be beneficial for host metabolism and significantly downregulated in high-fat diet–fed mice. Further experiments revealed that puerarin increased intestinal expression levels of Muc2 and Reg3g and protected intestinal barrier function (normal permeability) by increasing the expression of ZO-1 and occludin in vivo and in vitro. These data suggest that puerarin’s enriching effect on A. muciniphila is mediated, at least in part, by a host cellular response to protect the host from diet-induced metabolic disorders and other diseases.

Neuroendocrine carcinoma of the esophagus with an adenocarcinoma component

A 68-year-old male was referred with dysphagia. Endoscopic findings showed circular stenosis with a protruding mass in the lower esophagus. Biopsy showed adenocarcinoma and there was no evidence of distant metastases. A subtotal esophagectomy was performed. The resected specimen revealed a mixed neuroendocrine carcinoma with adenocarcinoma. The adenocarcinoma component was on the surface of the tumor and the neuroendocrine component invaded the deeper portion. Immunohistochemically, the neuroendocrine carcinoma component stained positive for cytokeratin 7 and cytokeratin 20, suggesting that the neuroendocrine carcinoma originated from the adenocarcinoma. The adenocarcinoma component stained positive for MUC2, which suggests that the adenocarcinoma component originated from Barrett's epithelium. Taken together, the neuroendocrine carcinoma may have originated from Barrett's epithelium. A metastasis to the liver was found 2 months after the surgical resection. Chemotherapy was administered, but there was no response. Most esophageal neuroendocrine carcinomas are accompanied by adenocarcinoma or squamous cell components, suggesting that these carcinomas originate from pluripotent cells in squamous or Barrett's epithelium. Appropriate chemotherapy for these lesions should be considered based on the cell of origin.

Combined EsophaCap cytology and MUC2 immunohistochemistry for screening of intestinal metaplasia, dysplasia and carcinoma

Purpose: The incidence of esophageal adenocarcinoma (EAC) has increased by 700% in Western countries over the last 30 years. Although clinical guidelines call for endoscopic surveillance for EAC among high-risk populations, fewer than 5% of new EAC patients are under surveillance at the time of diagnosis. We studied the accuracy of combined cytopathology and MUC2 immunohistochemistry (IHC) for screening of Intestinal Metaplasia (IM), dysplasia and EAC, using specimens collected from the EsophaCap swallowable encapsulated cytology sponge from Canada and United States. Patients and methods: By comparing the EsophaCap cytological diagnosis with concurrent endoscopic biopsies performed on the same patients in 28 cases, we first built up the cytology diagnostic categories and criteria. Based on these criteria, 136 cases were evaluated by both cytology and MUC2 IHC with blinded to patient biopsy diagnosis. Results: We first set up categories and criteria for cytological diagnosis of EscophaCap samples. Based on these, we divided our evaluated cytological samples into two groups: non-IM group and IM or dysplasia or adenocarcinoma group. Using the biopsy as our gold standard to screen IM, dysplasia and EAC by combined cytology and MUC2 IHC, the sensitivity and specificity were 68% and 91%, respectively, which is in the range of clinically useful cytological screening tests such as the cervical Pap smear. Conclusions: Combined EsophaCap cytology and MUC2 IHC could be a good screening test for IM and Beyond.

EXPRESSION OF MUC2 GLYCOPROTEIN ANTIBODY AND VASCULAR ENDOTHELIAL GROWTH FACTOR IN BARRETT'S MUCOSA

Higher expression of the mucin 2 (MUC2) glycoprotein and vascular endothelial growth factor (VEGF) in Barrett's mucosa may be associated with a higher risk of esophageal adenocarcinoma development. Thirty-six patients diagnosed with Barrett's esophagus (BE), short-segment, were included in the study due to unsuccessful treatment with proton pump inhibitors. The diagnosis was confirmed by histopathologic analysis of the tissue obtained by esophagogastric junction biopsy. Expression of MUC2 and VEGF was determined by immunohistochemistry. We found four patients in early stage of adenocarcinoma and 32 patients with BE; five of them had indication for argon plasma coagulation treatment, one for radiofrequency ablation and one for endoscopic mucosal resection; 25 patients were treated with proton pump inhibitors. Regression of BE occurred in 25 (69.44%) patients. MUC2 positivity is unique for goblet cells in patients with BE, but it is not the only marker. VEGF is an indicator of angiogenesis in the mucosa of patients with BE and adenocarcinoma.

Histopathology of Barrett’s Esophagus and Early-Stage Esophageal Adenocarcinoma: An Updated Review

Esophageal adenocarcinoma carries a very poor prognosis. For this reason, it is critical to have cost-effective surveillance and prevention strategies and early and accurate diagnosis, as well as evidence-based treatment guidelines. Barrett’s esophagus is the most important precursor lesion for esophageal adenocarcinoma, which follows a defined metaplasia–dysplasia–carcinoma sequence. Accurate recognition of dysplasia in Barrett’s esophagus is crucial due to its pivotal prognostic value. For early-stage esophageal adenocarcinoma, depth of submucosal invasion is a key prognostic factor. Our systematic review of all published data demonstrates a “rule of doubling” for the frequency of lymph node metastases: tumor invasion into each progressively deeper third of submucosal layer corresponds with a twofold increase in the risk of nodal metastases (9.9% in the superficial third of submucosa (sm1) group, 22.0% in the middle third of submucosa (sm2) group, and 40.7% in deep third of submucosa (sm3) group). Other important risk factors include lymphovascular invasion, tumor differentiation, and the recently reported tumor budding. In this review, we provide a concise update on the histopathological features, ancillary studies, molecular signatures, and surveillance/management guidelines along the natural history from Barrett’s esophagus to early stage invasive adenocarcinoma for practicing pathologists.

Histology of Barrett's Metaplasia: Do Goblet Cells Matter?

This review has provided a summary of the biology of goblet cell metaplasia in CLE as it pertains to BE. Goblet cells are terminally differentiated nonproliferative cells that have many overlapping histochemical characteristics with mucinous columnar cells and pseudogoblet cells. There is an abundance of evidence that suggests that use of goblet cells as a biomarker of BE, and its progression to malignancy, is problematic. Some of these limitations include the fact that the background non-goblet epithelium in most patients with CLE is biologically intestinalized and contains molecular abnormalities similar to goblet cell CLE, goblet cells fluctuate with time and decrease in number with progression of neoplasia, and pathologists have problems with interpretation, and distinction, of goblet cells from other types of cells in the esophagus. Sampling error results in sensitivity and specificity issues that limit its positive predictive value. Goblet cells are fewest in number in the same population of patients with CLE that are hardest to detect endoscopically (i.e., those with short or ultrashort CLE). Nevertheless, the risk of cancer in patients with short-segment BE, a condition difficult to distinguish from the stomach, is very low regardless of the presence or absence of goblet cells so it is unclear what the role of goblet cells is in these patients as a biomarker. Nevertheless, if the answer to the following question, "Would you as a gastroenterologist recommend surveillance for a patient with clear endoscopic evidence of CLE, particularly if it is ≥ 3 cm in length, but in which goblet cells were not reported to be present by the pathologist," is yes, then the US requirement for goblet cells as part of the criteria for "BE" is superfluous.

Australian clinical practice guidelines for the diagnosis and management of Barrett's esophagus and early esophageal adenocarcinoma

Barrett's esophagus (BE), a common condition, is the only known precursor to esophageal adenocarcinoma (EAC). There is uncertainty about the best way to manage BE as most people with BE never develop EAC and most patients diagnosed with EAC have no preceding diagnosis of BE. Moreover, there have been recent advances in knowledge and practice about the management of BE and early EAC. To aid clinical decision making in this rapidly moving field, Cancer Council Australia convened an expert working party to identify pertinent clinical questions. The questions covered a wide range of topics including endoscopic and histological definitions of BE and early EAC; prevalence, incidence, natural history, and risk factors for BE; and methods for managing BE and early EAC. The latter considered modification of lifestyle factors; screening and surveillance strategies; and medical, endoscopic, and surgical interventions. To answer each question, the working party systematically reviewed the literature and developed a set of recommendations through consensus. Evidence underpinning each recommendation was rated according to quality and applicability.

Mechanisms of Barrett's oesophagus: intestinal differentiation, stem cells, and tissue models

Barrett's oesophagus (BE) is defined as any metaplastic columnar epithelium in the distal oesophagus which replaces normal squamous epithelium and which predisposes to cancer development. It is this second requirement, the predisposition to cancer, which makes this condition both clinically highly relevant and an important area for ongoing research. While BE has been defined pathologically since the 1950's (Allison and Johnstone, Thorax 1955), and identified as a risk factor for esophageal adenocarcinoma since the 1970's (Naef A.P., et al J Thorac Cardiovasc Surg. 1975), our understanding of the molecular events giving rise to this condition remains limited. Herein we will examine what is known about the intestinal features of BE and how well it recapitulates the intestinal epithelium, including stem identity and function. Finally, we will explore laboratory models of this condition presently in use and under development, to identify new insights they may provide into this important clinical condition.

Barrett oesophagus: lessons on its origins from the lesion itself

Barrett oesophagus develops when the lower oesophageal squamous epithelium is replaced with columnar epithelium, which shows both intestinal and gastric differentiation. No consensus has been reached on the origin of Barrett oesophagus. Theories include a direct origin from the oesophageal-stratified squamous epithelium, or by proximal migration of the gastric cardiac epithelium with subsequent intestinalization. Variations of this theory suggest the origin is a distinctive cell at the squamocolumnar junction, the oesophageal gland ducts, or circulating bone-marrow-derived cells. Much of the supporting evidence comes from experimental models and not from studies of Barrett mucosa. In this Perspectives article, we look at the Barrett lesion itself: at its phenotype, its complexity, its clonal architecture and its stem cell organization. We conclude that Barrett glands are unique structures, but share many similarities with gastric glands undergoing the process of intestinal metaplasia. We conclude that current evidence most strongly supports an origin from stem cells in the cardia.

CDX-2, MUC-2 and B-catenin as intestinal markers in pure mucinous carcinoma of the breast

Background

Pure mucinous adenocarcinoma of the breast is a rare entity characterized by the production of variable amounts of mucin comprising 1% to 6% of breast carcinomas. Some mucinous adenocarcinomas have shown expression of intestinal differentiation markers such as MUC-2. This study examines the expression of intestinal differentiation markers in this type of breast carcinoma.

Results

Twenty-two cases of pure mucinous adenocarcinoma of the breast were assessed. Immunochemistry was performed for beta-catenin, CDX-2 and MUC-2. All cases were positive for B-catenin. MUC-2 positivity was observed in all cases; 63. 6% were 3 plus positive. All cases were negative for CDX-2.

Conclusions

These results suggest that mucinous breast carcinomas express some markers of intestinal differentiation, such as MUC-2 and beta-catenin; however, future studies with a larger series of cases and using molecular techniques that help affirm these results are needed.

A pSMAD/CDX2 complex is essential for the intestinalization of epithelial metaplasia

The molecular mechanisms leading to epithelial metaplasias are poorly understood. Barrett's esophagus is a premalignant metaplastic change of the esophageal epithelium into columnar epithelium, occurring in patients suffering from gastroesophageal reflux disease. Mechanisms behind the development of the intestinal subtype, which is associated with the highest cancer risk, are unclear. In humans, it has been suggested that a nonspecialized columnar metaplasia precedes the development of intestinal metaplasia. Here, we propose that a complex made up of at least two factors needs to be activated simultaneously to drive the expression of intestinal type of genes. Using unique animal models and robust in vitro assays, we show that the nonspecialized columnar metaplasia is a precursor of intestinal metaplasia and that pSMAD/CDX2 interaction is essential for the switch toward an intestinal phenotype.

Barrett esophagus: diagnostic challenges

The incidence of esophageal adenocarcinoma and associated mortality has risen dramatically over the past several decades, and, thus, it is increasingly important to understand its pathogenesis and risk factors. Barrett esophagus is the established precursor to esophageal adenocarcinoma that progresses through a metaplasia-dysplasia-carcinoma sequence. Its risk of transforming to carcinoma is not as high as previously reported and there appears to be a biological heterogeneity among patients with this disease. The overall prevalence of Barrett esophagus in the United States ranges from 1% to 25% and is closer to 5% in patients with gastroesophageal reflux disease. Because of the frequency of Barrett esophagus and associated implications, it is important for the practicing pathologist to have a thorough understanding of this disease and its diagnostic pitfalls. In this review, we will discuss issues associated with the diagnosis of Barrett esophagus, including the definition of Barrett esophagus and its distinction from carditis with intestinal metaplasia. We will also discuss challenges in the grading of dysplasia and new variants of dysplasia, including crypt dysplasia and foveolar-type dysplasia. Finally, we will touch upon the evaluation of dysplasia in endoscopic mucosal resection specimens.

[Barrett's esophagus. An update]

Barrett's esophagus (BE), a well-known complication of gastroesophageal reflux disease (GERD), constitutes a precancerous condition for adenocarcinoma of the distal esophagus. The so-called Barrett's carcinoma shows increasing incidences in countries of the western hemisphere; new data, however, indicate that the rise in incidence is not quite as dramatic as previously assumed. The definition of BE is currently changing: despite good reasons for a purely endoscopic definition of BE, goblet cells are still mandatory for this diagnosis in Germany and the USA. Dysplastic changes in the epithelium are the most important risk factor for the development of Barrett's adenocarcinoma and recently dysplasia was subclassified into a more frequent adenomatous (intestinal) and a non-adenomatous (gastric-foveolar) types. The gold standard for diagnosing dysplasia is still H&E staining. The histological diagnosis of dysplasia is still encumbered by a significant interobserver variability, especially regarding the differentiation between low grade dysplasia and inflammatory/reactive changes and the discrimination between high grade dysplasia and adenocarcinoma. Current data, however, show much higher interobserver agreement in endoscopic resection specimens than in biopsies. Nevertheless, the histological diagnosis of dysplasia should be corroborated by an external second opinion because of its clinical consequences. In endoscopic resections of early Barrett's adenocarcinoma, the pathological report has to include a risk stratification for the likelihood of lymphogenic metastases.

Divergent expression of MUC5AC, MUC6, MUC2, CD10, and CDX-2 in dysplasia and intramucosal adenocarcinomas with intestinal and foveolar morphology: is this evidence of distinct gastric and intestinal pathways to carcinogenesis in Barrett Esophagus?

Dysplasia in Barrett esophagus has been recognized to be morphologically heterogenous, featuring adenomatous, foveolar, and hybrid phenotypes. Recent studies have suggested a tumor suppressor role for CDX-2 in the metaplasia-dysplasia-carcinoma sequence. The phenotypic stability and role of CDX-2 in the neoplastic progression of different types of dysplasias have not been evaluated. Thirty-eight endoscopic mucosal resections with dysplasia and/or intramucosal carcinoma (IMC) arising in Barrett esophagus were evaluated for the expression of MUC5AC, MUC6, MUC2, CD10, and CDX-2. The background mucosa was also evaluated. The results were correlated with morphologic classification and clinicopathologic parameters. Of 38 endoscopic mucosal resections, 23 had IMC and dysplasia, 8 had IMC only, and 7 had dysplasia only. Among dysplastic lesions, 73% were foveolar, 17% were adenomatous, and 10% were hybrid. Twenty of 23 cases with dysplasia and adjacent IMC showed an identical immunophenotype of dysplasia and IMC comprising 16 gastric, 3 intestinal, and 1 mixed immunophenotype. Three cases showed discordance of dysplasia and IMC immunophenotype. These findings suggest that most Barrett-related IMC cases are either gastric or intestinal, with phenotypic stability during progression supporting separate gastric and intestinal pathways of carcinogenesis. CDX-2 showed gradual downregulation of expression during progression in adenomatous dysplasia but not in foveolar or hybrid dysplasia, supporting a tumor suppressor role, at least in the intestinal pathway. CDX-2 was also found to be expressed to a greater degree in intestinal metaplasia compared with nonintestinalized columnar metaplasia. Consistent with CDX-2 as a tumor suppressor, this suggests that nonintestinalized columnar metaplasia may be an unstable intermediate state at risk for neoplastic progression.

Chinese National Consensus on diagnosis and management of Barrett's esophagus (BE): revised edition, June 2011, Chongqing, China

To standardize the diagnosis and management of Barrett's esophagus (BE) in China, the Chinese Society of Gastroenterology convened the Second National Conference on BE in June 2011 in Chongqing, China. After intense discussion among experts in this field and an extensive review of the literature, a revised consensus on the diagnosis and management of BE was generated.