Cytokeratin and CDX-2 expression in Barrett's esophagus

OBJECTIVE: Barrett's esophagus (BE) is a premalignant condition of the distal esophagus. For diagnostic purposes it is important to find biomarkers that can specifically identify BE, for instance to differentiate BE epithelial cells from gastric cardia epithelial cells in brush cytology specimens. The objective of this study was to determine the specificity of CDX-2 and a set of cytokeratins (CKs) as specific markers for BE as compared with normal squamous esophageal and gastric cardia tissue. MATERIAL AND METHODS: Immunohistochemistry (IHC) with specific antibodies against CDX-2, and a set of CKs was performed on fresh frozen consecutive tissue sections of normal squamous, gastric cardia and non-dysplastic BE of 80 patients. RESULTS: IHC results showed CK8, CK18 and CK20 expression in both BE and gastric cardia, while CK7 was seen in all BE but also in 26% of gastric cardia biopsies. CK10/13 was only expressed in normal squamous epithelium. CDX-2 nuclear staining was found in 87.5% of the BE biopsies, whereas normal squamous esophagus and cardia biopsies were negative. CONCLUSIONS: CDX-2 in combination with a set of CKs can be used as biomarkers to distinguish between BE and normal squamous esophagus. In order to distinguish BE from cardia tissue, a combination of CDX-2 and CK7 is most informative.     

Cytokeratin and CDX-2 expression in Barrett's esophagus

Objective. Barrett's esophagus (BE) is a premalignant condition of the distal esophagus. For diagnostic purposes it is important to find biomarkers that can specifically identify BE, for instance to differentiate BE epithelial cells from gastric cardia epithelial cells in brush cytology specimens. The objective of this study was to determine the specificity of CDX-2 and a set of cytokeratins (CKs) as specific markers for BE as compared with normal squamous esophageal and gastric cardia tissue. Material andmethods. Immunohistochemistry (IHC) with specific antibodies against CDX-2, and a set of CKs was performed on fresh frozen consecutive tissue sections of normal squamous, gastric cardia and non-dysplastic BE of 80 patients. Results. IHC results showed CK8, CK18 and CK20 expression in both BE and gastric cardia, while CK7 was seen in all BE but also in 26% of gastric cardia biopsies. CK10/13 was only expressed in normal squamous epithelium. CDX-2 nuclear staining was found in 87.5% of the BE biopsies, whereas normal squamous esophagus and cardia biopsies were negative. Conclusions. CDX-2 in combination with a set of CKs can be used as biomarkers to distinguish between BE and normal squamous esophagus. In order to distinguish BE from cardia tissue, a combination of CDX-2 and CK7 is most informative.     

Evaluation of Barrett's esophagus with CK7, CK20, p53, Ki67, and COX2 expressions using chromoendoscopical examination

Barrett's esophagus (BE) is a complication of chronic gastroesophageal reflux disease and can be diagnosed when there is an endoscopically irregular Z‐line and intestinal metaplasia (IM) in a biopsy obtained lower esophagus. It is still not clear whether IM in the gastric cardia or columnar mucosa without IM in the lower esophagus have any significance as BE, which is considered as preneoplastic. The aim of the study was to determine the immunohistochemical features of BE and columnar mucosa in the distal esophagus and also to evaluate the value of chromoendoscopy in the diagnosis of BE in a prospective manner. A total of 12 chromoendoscopic biopsies (six from normal‐looking unstained esophagus and six from esophageal mucosa stained with methyl blue suspicious of BE) were taken from 111 cases who underwent endoscopy because of a variety of upper gastrointestinal symptoms. Immunohistochemical analysis was performed using CK7, CK20, p53, Ki67, and cyclooxygenase 2 (COX2). Of the 111 cases, 19 cases with carcinoma (nine adeno, six squamous, four undifferentiated carcinomas) and 17 cases with normal squamous epithelium were excluded, while 75 cases showing columnar epithelium, including 46 (61.3%) with IM and 29 (38,7%) without IM, were further evaluated immunohistochemically. CK7 was observed in surface, crypt, and glandular epithelium, whereas CK20 was expressed in surface and superficial crypt epithelium. No significant difference was observed between the Barrett and non‐Barrett type of CK7/20 staining pattern (P > 0,05). Expression of p53 did not show any difference between BE and columnar mucosa without IM, whereas COX2 expression was significantly increased in BE (P < 0.05) in comparison with columnar mucosa without IM. Ki67 expression was significiantly higher both in upper and lower crypts in BE (P < 0.05). The present study showed that a Barrett pattern does not seem to exist; however, the analysis of COX2 expression and the Ki67 proliferation fraction by immunohistochemistry can be used to separate BE from non‐Barrett's metaplasia of the distal esophagus. In our point of view, the immunohistochemical detection of p53 expression in Barrett's metaplasia stage is useless as a marker for early detection of high‐risk patients.     

Bone morphogenetic protein 4 expressed in esophagitis induces a columnar phenotype in esophageal squamous cells

BACKGROUND & AIMS: Barrett's esophagus (BE) is a metaplastic condition in which normal squamous esophageal epithelium is replaced by columnar epithelium. It is proposed that one of the possible mechanisms is dedifferentiation of squamous epithelium into columnar epithelium. The pathophysiology through which this metaplasia occurs is unknown. A recent study by serial analysis of gene expression showed that bone morphogenetic protein 4 (BMP-4) is uniquely expressed in BE. In this study, the role of the BMP pathway in the metaplastic transformation of normal squamous cells into columnar cells was examined. METHODS: Tissues from patients with esophagitis and BE and in an esophagitis-BE rat model were examined for the activation of the BMP pathway. Short-term cultures of primary normal squamous esophageal cells were treated with BMP-4, and cell biological changes were examined by Western blot analysis, immunohistochemistry, and microarrays. RESULTS: In both human and rat tissues, the BMP pathway proved to be activated in esophagitis and BE. Upon incubation of squamous cell cultures with BMP-4, the cytokeratin expression pattern showed a shift that was consistent with columnar epithelium. Involvement of the BMP pathway was suggested by up-regulation of Phosphorylated-Smad 1/5/8 (P-Smad 1/5/8) that was effectively blocked by Noggin, a BMP antagonist. Comparison of the gene expression profiles of squamous cells, BMP-4-treated squamous cells, and BE cells showed a significant shift in the profile of the BMP-4-treated squamous cells toward that of the cultured BE cells. CONCLUSIONS: These results suggest that the BMP pathway could play a role in the transformation of normal esophageal squamous cells into columnar cells.     

Is intestinal metaplasia a necessary precursor lesion for adenocarcinomas of the distal esophagus,gastroesophageal junction and gastric cardia?

Adenocarcinoma of the distal esophagus and gastroesophageal junction are believed to arise in Barrett's esophagus with intestinal metaplasia. Whether adenocarcinoma can arise in columnar lined esophagus without intestinal metaplasia is in doubt. Whether adenocarcinoma of the gastric cardia arises in intestinal metaplasia of the gastric cardia is also in doubt. We aim to evaluate the relationship of size and stage of adenocarcinoma of the distal esophagus, gastroesophageal junction and gastric cardia to intestinal metaplasia and other types of columnar epithelium. Seventy-four patients who had esophagogastrectomy for adenocarcinomas in this region were examined histologically to assess the frequency of residual intestinal metaplasia in the surrounding epithelium. Tumors without residual intestinal metaplasia were evaluated for the presence of other columnar epithelia and correlated with tumor size and stage. Cardiac mucosa was present around all tumors. Residual intestinal metaplasia was present in 48 (65%) tumors, including 33/38 (87%) distal esophageal, 10/25 (45%) junctional and 5/11 (45%) gastric cardia tumors. The prevalence of intestinal metaplasia was 100% in all tumors that were less than 1 cm in maximum diameter and all intramucosal tumors. The prevalence of residual intestinal metaplasia decreased with increasing tumor size and stage. These data strongly support the contention that adenocarcinomas of this region, including those in the gastric cardia, arise in intestinal metaplastic epithelium. The absence of residual intestinal metaplasia in larger tumors is the result of tumor overgrowing the intestinal metaplasia from which it arose.     

Cytokeratin subsets for distinguishing Barrett's esophagus from intestinal metaplasia in the cardia using endoscopic biopsy specimens

OBJECTIVES: It has been suggested that Barrett's epithelium and intestinal metaplasia in the gastric cardia have different cyotokeratin (CK) staining patterns and that Barrett's epithelium can be distinguished by CK staining pattern. The aim of this study was to test the utility of CK staining for distinguishing Barrett's esophagus from gastric intestinal metaplasia. METHODS: Topographically mapped gastric biopsy specimens were obtained from patients without Barrett's esophagus, and esophageal biopsies were obtained from patients with long-segment Barrett's esophagus (>3 cm). Serial sections were stained with Genta or El-Zimaity triple stain, and biopsies with intestinal metaplasia were stained with antibodies against CK 4, 13, 7, and 20. RESULTS: Sections from 33 biopsies with Barrett's esophagus, 23 with intestinal metaplasia of the gastric cardia, 27 with intestinal metaplasia of the gastric body, and 33 with intestinal metaplasia of the antrum were examined. CK 4 and CK 13 stained squamous epithelium only. The proposed "diagnostic" CK Barrett's 7/20 pattern was found in only 39% of long-segment Barrett's compared to 35%, 4%, and 24% in intestinal metaplasia from the gastric cardia, body, and antrum, respectively. The criteria proposed had a sensitivity of 45% and a specificity of 65%. CONCLUSIONS: These results do not support keratin phenotyping as a tool for differentiating intestinal metaplasia originating in the cardia from intestinal metaplasia of Barrett's.     

Cyclooxygenase 2 expression in Barrett's esophagus and adenocarcinoma: Ex vivo induction by bile salts and acid exposure

BACKGROUND & AIMS: Barrett's esophagus (BE) results from chronic, severe gastroesophageal reflux and predisposes to esophageal adenocarcinoma. Cyclooxygenase (COX)-2 is involved in chronic inflammation and epithelial cell growth. We investigated COX-2 expression in BE and esophageal adenocarcinoma to explore a potential relation between COX-2 expression and metaplasia or carcinogenesis. METHODS: Endoscopic mucosal biopsy specimens of Barrett's intestinal metaplasia (n = 30), Barrett's dysplasia (n = 11), and esophageal adenocarcinoma (n = 5) were compared with normal esophagus (n = 46) and duodenum (n = 46) and analyzed by Western blotting and immunohistochemistry. RESULTS: Immunoblots revealed constitutive expression of COX-2 in normal esophagus and duodenum. COX-2 protein expression was significantly higher in patients with Barrett's metaplasia, dysplasia, and adenocarcinoma compared with normal squamous esophageal or columnar duodenal epithelia and was heterogenous in different regions of the BE surface. Immunohistochemistry revealed prominent staining in the glands of BE, dysplasia, and adenocarcinoma and faint staining in the basal layers of squamous esophagus and the surface of the duodenum. In response to pulses of acid or bile salts in an ex vivo organ culture system, COX-2 expression increased significantly in BE tissues, and this effect was attenuated by the selective COX-2 inhibitor NS-398. CONCLUSIONS: The results show COX-2 expression in normal esophagus, which increases significantly in BE and esophageal adenocarcinoma. COX-2 is regulated ex vivo by exposure to acid or bile salts.     

Development of Barrett's esophagus six months after total gastrectomy

Barrett's esophagus (BE) is an acquired disease of the esophagus, in which esophageal squamous epithelium is changed by injury from reflux to metaplastic intestinal type columnar epithelium. BE is the premalignant lesion of adenocarcinoma of the esophagus. It is widely accepted that the long-standing reflux of gastric acid is a catalyst for the development of BE. More recent work points toward the reflux of duodenal secretions as a catalyst in this disease process as well. Moreover, the time course for the development of BE once a patient has reflux is not known. Our case challenges the currently defined time course of "long-standing" reflux symptoms for the development of BE, and supports the role of duodenal secretions alone in the development of BE. A 68-yr-old Caucasian man was admitted with weight loss, left upper quadrant pain, a hemoglobin of 6.8, and heme-positive stool. Esophagogastroduodenoscopy (EGD) revealed normal esophageal mucosa and a mass in the gastric cardia. Biopsies showed moderately differentiated gastric adenocarcinoma. The patient underwent a total gastrectomy, distal esophagectomy, and a Roux-en-Y esophagojejunostomy. Pathology confirmed gastric adenocarcinoma (T1 N0 Mx). The distal esophagus and gastroesophageal junction in the resected specimen were grossly and microscopically normal. Six months later an EGD, prompted by new complaints of regurgitation and dyspepsia, revealed distal esophageal mucosa lined by red-colored columnar tissue. Biopsies showed intestinal type epithelium. Thus, our case report's contribution to the current literature is twofold. It provides evidence of development of BE solely from duodenal reflux, and it documents a relatively short time span to development of BE.     

Gene expression profiling in Barrett＇s esophagus and cardia intestinal metaplasia： A comparative analysis using cDNA microarray

AIM: To study the difference of gene expression profile changes in Barrett‘s esophagus (BE) and cardia intestinal metaplasia (CIM) and to screen the novel genes in the early stage by cDNA microarray.METHODS: cDNA retrotranscribed from an equal amount of mRNA from BE and CIM epithelial tissues was labeled with Cy3 and Cy5 fluorescence as probes. The mixed probe was hybridized with three pieces of BiostarH-40 s double dot human whole gene chip. The chips were scanned with a ScanArray 4000. The acquired images were analyzed using GenePix Pro 3.0 software.RESULTS: A total of 141 genes were screened out that exhibited different expression in all three chips. There were 74 upregulated and 67 downregulated genes in gene expression profiles of BE which were two times of that in CIM.CONCLUSION: There is a difference in gene expression level between BE and CIM epithelia. These 141 genes probably relate to the occurrence and development of BE and the progression to adenocarcinoma.     

Human papillomavirus and the risk of Barrett's esophagus

Human papillomavirus (HPV) is strongly associated with squamous esophageal cancer. The potential role of HPV in Barrett's esophagus (BE) has been examined but remains unclear. The aim of the study was to determine the prevalence of HPV in esophageal and gastric tissues obtained from patients with and without BE. We designed a cross‐sectional study was conducted with prospective enrollment of eligible patients scheduled for esophagogastroduodenoscopy (EGD). All participants had biopsies of endoscopic BE, squamous‐lined esophagus, and stomach. Immunohistochemistry (IHC) on formalin‐fixed and paraffin‐embedded tissue was conducted using monoclonal antibodies. Polymerase chain reaction (PCR) for HPV was performed on DNA extracted from esophageal biopsies snapped frozen within 30 minutes after endoscopic capture. The Roche HPV Linear Array Assay with PGMY primers that has high sensitivity for detecting 37 types of HPV was used. A total of 127 subjects were included: 39 with definitive BE had IHC done on samples from non‐dysplastic BE, squamous esophagus, gastric cardia, and gastric body; and 88 control patients without BE had IHC done on squamous esophageal samples, gastric cardia, and gastric body. HPV was not detected in any of the samples in either group. For confirmation, HPV DNA PCR was performed on randomly selected samples from 66 patients (both esophagus and BE from 13 patients with BE, and 53 esophagus from patients without BE); no sample had HPV DNA detected via PCR in the presence of adequate quality control. HPV infection does not play a role in the formation of non‐dysplastic Barrett's esophagus in men in the United States.     

Usefulness of cytokeratin immunoreactivity pattern for distinction of Barrett's esophagus from intestinal metaplasia of the stomach

The histological distinction between Barrett's esophagus involving the distal esophagus and intestinal metaplasia of the stomach has important clinical implications and can be difficult even with the use of histochemical stains. Cytokeratin (CK) 7 and 20 are cytoplastic structural proteins that show restricted expression in normal and malignant epithelia of the gastrointestinal tract. CK7 and 20 immunostaining were performed on a 67-year-old male with cardiac cancer with reflux esophagitis due to sliding hernia. The CK7/20 immunoreactivity pattern of cancer and reflux esophagitis in this case showed superficial CK20 staining and strong CK7 staining of both superficial and deep glands. In intestinal metaplasia of the stomach, strong CK20 immunostaining in superficial and deep glands and absent CK7 immunoreactivity were noted. Neither CK7 nor CK20 immunoreactivity was noted in squamous cell epithelium. Therefore, we concluded that in this patient intestinal metaplasia of the esophagus was BE. The CK7/20 reactivity pattern is useful for identifying the intestinal metaplasia of the esophagus from the stomach using histological materials from biopsy and surgically resected specimens.     

食管胃连接处疾病的病因学和形态学研究现状

食管胃连接处（EGJ）系指食管与胃的交界,其组织学具有特殊性。贲门部是连接远端食管与胃底黏膜的区域,贲门是否存在及其真实长度仍存有争议。EGJ所涉及的疾病主要有贲门炎、反流性食管炎（RE）和Barrett食管（BE）,三者间存在一定的联系.     

Expression of Resistin-like Molecule Beta in Barrett’s Esophagus: A Novel Biomarker for Metaplastic Epithelium

The formation of goblet cells characterizes the intestinal metaplasia of Barrett’s esophagus (BE). Hematoxylin-eosin (HE) staining may fail to show intestinal metaplasia in BE, and PAS-Alcian Blue may present difficulties of interpretation due to its more heterogeneous staining. Recent evidence indicates that expression of resistin-like molecule beta (RELMβ), a goblet cell-specific protein, is uniquely restricted to intestinal epithelium. However, it still remains largely unknown whether RELMβ can be served as a biomarker for metaplastic epithelium of BE. In this study, 104 biopsy specimens of the distal esophagus from 88 suspected BE patients were collected, including 56 suspected intestinal metaplasia, 26 gastric type mucosa, and 22 squamous epithelium. We evaluated the RELMβ expression in these biopsy specimens, and compared with those of CDX-2 immunostaining and PAS-Alcian Blue staining (pH 2.5). Of the suspected intestinal metaplasia specimens, 46 presented intestinal-type goblet cells and were immunostaining positive for RELMβ and CDX-2, the remaining ten possessed only goblet cell mimickers and were not reactive with RELMβ and CDX-2. Of the gastric-type mucosa specimens, none reacted with either RELMβ or CDX-2. Moreover, the squamous epithelium was not reactive with RELMβ and CDX-2. Acid mucin was present in goblet cells in all cases of BE and columnar cells in ten gastric specimens. In addition, the reactivity of RELMβ was enhanced in six BE specimens with dysplasia. These results provide evidence that RELMβ protein may be a novel biomarker to distinguish the intestinal-type goblet cells and goblet cell mimickers, and useful in the correct diagnosis of BE.     

Visible endoscopic and histologic changes in the cardia, before and after complete Barrett's esophagus ablation

BACKGROUND: Adverse events associated with the thermal ablation of Barrett's esophagus (BE) include the generation of gastric mucosa buried beneath the neosquamous regrowth, and unrecognized development and growth of adenocarcinomas. No reports exist regarding the endoscopic appearance and histology of the cardia before and after BE ablation. The aim of our study was to assess the relative frequency of the occurrence of visible endoscopic and histologic changes in the cardia, before and after complete BE ablation. METHODS: A subset analysis of patients with uncomplicated BE, BE with dysplasia, or early carcinoma, who had been enrolled into one of 4 ongoing prospective studies of mucosal ablation, was examined. Eighty-two patients were identified who entered a BE ablation study, with 75 of these completing BE mucosal ablation. Cardia biopsy specimens were taken in all patients before ablation and serially after BE ablation. Cardia histology was graded by using the modified Sydney System for gastritis. RESULTS: Before ablation, cardia nodules were noted in 3, cardia intestinal metaplasia (IM) in 7 (8.5%), and none harbored cardia dysplasia. Postablation surveillance ranged from 3 to 75 months (mean 31.1 months [19.5]). Six subjects (8%) developed cardia nodules during surveillance; cardia IM was found in 21(28%), with 17 of these being a new finding (incidence of 25%). Cardia low-grade dysplasia incidence was 1.3% and high-grade dysplasia was 4% after BE ablation. CONCLUSIONS: The pathophysiology of the abnormal cardia histology and the endoscopic lesions (nodules) is unclear, but endoscopic surveillance of not only the neosquamous epithelium but also the cardia should be considered after ablation, especially in those high-grade dysplasia and early adenocarcinoma BE patients.     

The role of gastric carditis in metaplasia and neoplasia at the gastroesophageal junction.

Adenocarcinomas at the gastroesophageal junction appear to arise from foci of intestinal metaplasia that develop either in the distal esophagus or the proximal stomach (the gastric cardia). Metaplasia is usually a consequence of chronic inflammation, and it is logical to assume that intestinal metaplasia at the gastroesophageal junction develops as a result of chronic inflammation in the epithelia that normally line the junction region. Intestinal metaplasia in the esophagus is known to be a sequela of chronic inflammation in squamous epithelium caused by gastroesophageal reflux disease, whereas intestinal metaplasia in the distal stomach is often a consequence of chronic gastritis caused by Helicobacter pylori infection. For the gastric cardia, the contributions of gastroesophageal reflux disease, H. pylori infection, and other factors to inflammation, metaplasia, and neoplasia are not clear. If physicians are to develop meaningful preventive strategies and specific therapies for tumors of the proximal stomach, a clear understanding of pathogenesis is important. Recent studies on pathogenetic factors for inflammation in cardiac epithelium (gastric carditis) have yielded contradictory results, perhaps because of fundamental differences in the techniques used by different investigators for identifying and sampling the gastric cardia. This report explores the roots of the controversy regarding the role of gastric carditis in the development of metaplasia and neoplasia at the gastroesophageal junction and suggests practical guidelines for biopsy protocols to be used in future studies that will be necessary to resolve these disputes.     

Specialized intestinal metaplasia of the distal esophagus in gastroesophageal reflux disease: prevalence and clinico-demographic features

BACKGROUND: Specialized intestinal metaplasia can be categorized according endoscopic and histological findings in long segment Barrett, short segment Barrett and specialized intestinal metaplasia of cardia. Barrett's esophagus is an acquired disease that is found in about 10%-13% of patients undergoing endoscopy for symptoms of gastroesophageal reflux disease and it is well established as predisposing to esophageal adenocarcinoma. The columnar epithelium with goblet cells replaces the normal squamous epithelium. OBJECTIVE: To determine the prevalence and clinical-demographic characteristics of specialized intestinal metaplasia of distal esophagus in the gastroesophageal reflux disease. METHODS: From April to October 2002, 402 patients referred to upper endoscopy due gastroesophageal reflux disease were evaluated through of a symptom questionnaire about clinical and demographic features and submitted to upper endoscopy with four-quadrant biopsies 1 cm below escamocolumnar junction. RESULTS: Eighteen point four percent of patients had specialized intestinal metaplasia, 0.5% long segment Barrett esophagus, 3.2% short segment Barrett's esophagus and 14.7% specialized intestinal metaplasia of cardia. Patients with Barrett's esophagus showed a tendency to be male and specialized metaplasia of cardia to be female. All patients with Barrett's esophagus were white. There was not association between symptoms of gastroesophageal reflux disease and specialized intestinal metaplasia, but patients with Barrett's esophagus showed a tendency to have symptoms over 5 years and had more hiatal hernia and esophagitis. The use of alcohol and tobacco was not related to the presence of specialized intestinal metaplasia. CONCLUSIONS: Barrett's esophagus was more related to the male gender, gastroesophageal reflux disease symptoms for 5 years or longer, more intense esophagitis and hiatal hernia, but was not related to the use of tobacco and alcohol.