Transcatheter aortic valve replacement: clinical safety and performance data.

Introduction: Patients with severe aortic stenosis and regurgitation who are inoperable or at high-risk for surgery can be treated with transcatheter aortic valve replacement (TAVR). The aim of this study was to provide a comprehensive overview of the literature of TAVR and reported clinical and performance outcomes. Areas covered: A total of 16 devices, described in 204 articles describing clinical and performance outcomes, were included. The most frequently observed outcome was 30-day mortality, ranging between 0-23%. Other commonly reported clinical outcomes were 30-day stroke, ranging between 0-14.3% and pacemaker implantation, ranging from 0-44.9%. The most common valve performance outcome was aortic valve regurgitation, however, mostly reported at 7 days follow-up. Next to a follow-up period of 30 days, numerous articles reported outcomes at 6 months and 1 year. The numbers of articles describing outcomes with a longer follow-up as well as including intermediate and low-risk patients were limited. Expert commentary: This literature review provided a clear overview of the reported clinical and performance outcomes of TAVR devices. Despite the frequently used VARC-2 definitions, we identified a huge variation across studies. Future studies using standardized definitions of study set-ups and outcomes are essential and might lead to better insights of TAVR.

Toll-like Receptor 2 Signalling and the Lysosomal Machinery in Barrett's Esophagus.

BACKGROUND AND AIMS: Inflammation plays an important role in the development of esophageal adenocarcinoma and its metaplastic precursor lesion, Barrett's esophagus. Toll-like receptor (TLR) 2 signalling and lysosomal function have been linked to inflammation-associated carcinogenesis. We examined the expression of TLR2 in the esophagus and the effect of long-term TLR2 activation on morphological changes and expression of factors involved in lysosomal function in a Barrett's esophagus epithelium cell line. METHODS: TLR2 expression in normal squamous esophagus, reflux esophagitis, Barrett's esophagus and esophageal adenocarcinoma biopsies was assessed with Q-RT-PCR, in situ hybridization and immunohistochemistry. Barrett's esophagus epithelium cells (BAR-T) were incubated with acid and bile salts in the presence or absence of the TLR2 agonist Pam3CSK4 for a period up to 4 weeks. Morphological changes were assessed with electron microscopy, while Q-RT-PCR was used to determine the expression of lysosomal enzymes (Cathepsin B and C) and factors involved in endocytosis (LAMP-1 and M6PR) and autophagy (LC3 and Rab7). RESULTS: TLR2 was expressed in normal squamous esophagus, reflux esophagitis, Barrett's esophagus but was most prominent in esophageal adenocarcinoma. Long-term TLR2 activation in acid and bile salts exposed BAR-T cells resulted in more and larger lysosomes, more mitochondria and increased expression of LAMP-1, M6PR, Cathepsin B and C when compared to BAR-T cells incubated with acid and bile salts but no TLR2 agonist. Factors associated with autophagy (LC3 and Rab7) expression remained largely unchanged. CONCLUSION: Activation of TLR2 in acid and bile salts exposed Barrett epithelium cells resulted in an increased number of mitochondria and lysosomes and increased expression of lysosomal enzymes and factors involved in endocytosis.

Correction: BMP4 Signaling Is Able to Induce an Epithelial-Mesenchymal Transition-Like Phenotype in Barrett's Esophagus and Esophageal Adenocarcinoma through Induction of SNAIL2.

[This corrects the article DOI: 10.1371/journal.pone.0155754.].

BMP4 Signaling Is Able to Induce an Epithelial-Mesenchymal Transition-Like Phenotype in Barrett's Esophagus and Esophageal Adenocarcinoma through Induction of SNAIL2.

BACKGROUND: Bone morphogenetic protein 4 (BMP4) signaling is involved in the development of Barrett's esophagus (BE), a precursor of esophageal adenocarcinoma (EAC). In various cancers, BMP4 has been found to induce epithelial-mesenchymal transition (EMT) but its function in the development of EAC is currently unclear. AIM: To investigate the expression of BMP4 and several members of the BMP4 pathway in EAC. Additionally, to determine the effect of BMP4 signaling in a human Barrett's esophagus (BAR-T) and adenocarcinoma (OE33) cell line. METHODS: Expression of BMP4, its downstream target ID2 and members of the BMP4 pathway were determined by Q-RT-PCR, immunohistochemistry and Western blot analysis using biopsy samples from EAC patients. BAR-T and OE33 cells were incubated with BMP4 or the BMP4 antagonist, Noggin, and cell viability and migration assays were performed. In addition, expression of factors associated with EMT (SNAIL2, CDH1, CDH2 and Vimentin) was evaluated by Q-RT-PCR and Western blot analysis. RESULTS: Compared to squamous epithelium (SQ), BMP4 expression was significantly upregulated in EAC and BE. In addition, the expression of ID2 was significantly upregulated in EAC and BE compared to SQ. Western blot analysis confirmed our results, showing an upregulated expression of BMP4 and ID2 in both BE and EAC. In addition, more phosphorylation of SMAD1/5/8 was observed. BMP4 incubation inhibited cell viability, but induced cell migration in both BAR-T and OE33 cells. Upon BMP4 incubation, SNAIL2 expression was significantly upregulated in BAR-T and OE33 cells while CDH1 expression was significantly downregulated. These results were confirmed by Western blot analysis. CONCLUSION: Our results indicate active BMP4 signaling in BE and EAC and suggest that this results in an invasive phenotype by inducing an EMT-like response through upregulation of SNAIL2 and subsequent downregulation of CDH1.

Patients With Barrett's Esophagus and Persistent Low-grade Dysplasia Have an Increased Risk for High-grade Dysplasia and Cancer.

BACKGROUND & AIMS: In some patients with Barrett's esophagus (BE) and a confirmed diagnosis of low-grade dysplasia (LGD), the LGD is not detected during follow-up examinations. We would like to avoid the unnecessary risks and costs of ablative treatment for these patients. Therefore, we investigated whether persistent LGD increases risk for high-grade dysplasia (HGD) or esophageal adenocarcinoma (EAC) and what proportion of patients are no longer found to have dysplasia after an initial diagnosis of LGD. METHODS: In a retrospective study, we collected information on 1579 patients with BE and LGD from 2005 through 2010 by using a nationwide registry of histopathology diagnoses in the Netherlands (PALGA). Confirmed LGD was defined as a diagnosis of LGD that was confirmed by any other pathologist. Persistent LGD was defined as LGD detected at the first and follow-up endoscopy. Data were collected on patients until treatment for HGD, detection of EAC, or the last endoscopy at which a biopsy was collected (through July 2014). We evaluated whether persistent LGD was a risk factor for malignant progression by using univariable and multivariable Cox regression analyses. RESULTS: Of individuals with BE and LGD in the database, the diagnosis of LGD was confirmed for 161 patients (10% of total). In these patients, the incidence of HGD and/or EAC was 5.18/100 person-years (95% confidence interval [CI], 4.32-8.10/100 person-years) compared with 1.85/100 person-years (95% CI, 1.52-2.22/100 person-years) in patients for whom LGD was not confirmed at the first endoscopy. The incidence of EAC alone in patients with confirmed LGD was 2.51/100 person-years (95% CI, 1.46-3.99/100 person-years), compared with 1.01/per 100 person-years (95% CI, 0.41-2.10/100 person-years) in patients for whom LGD was not confirmed at the first endoscopy. Of patients in whom LGD was confirmed at the first endoscopic examination, 51% were not found to have dysplasia at the first follow-up endoscopy, and 30% had persistent LGD. In patients with persistent LGD, the incidence of HGD and/or EAC was 7.65/100 person-years (95% CI, 4.45-12.34) and of only EAC was 2.04/100 person-years (95% CI, 0.65-4.92); in patients without persistent LGD, the incidence of HGD and/or EAC was 2.32/100 person-years (95% CI, 1.08-4.40/100 person-years) and of only EAC was 1.45 (95% CI, 0.53-3.21/100 person-years). Persistent LGD was found to be an independent risk factor for the development of HGD and/or EAC, with hazard ratio of 3.5 (95% CI, 1.48-8.28). CONCLUSIONS: In a large population-based cohort study of patients with BE and LGD, the risk of progression to HGD and/or EAC was higher in patients with confirmed LGD and highest in those with confirmed and persistent LGD.

Current understanding of the functional roles of aberrantly expressed microRNAs in esophageal cancer.

The incidence of esophageal cancer is rising, mostly because the increasing incidence of esophageal adenocarcinoma in Western countries. Despite improvements in diagnosis and treatment, the overall 5-year survival rates remain low. MicroRNAs (miRNAs) are small non-coding RNA molecules that regulate the expression of target genes. Recently, disease specific miRNAs have been identified, which act as tumor suppressors or oncogenes. In this review, we will summarize the current knowledge about the function of aberrantly expressed miRNAs in esophageal cancer. We selected 5 miRNAs (miRNA-21, -143, -145, -196a and let-7) based on the available literature, and described their potential role in regulating pathways that are deregulated in esophageal cancer. Finally we will highlight the current achievements of using and targeting miRNAs. Because these miRNAs likely have important regulatory roles in cancer development, they open a therapeutic window for new treatment modalities.

Cryospray ablation using pressurized CO2 for ablation of Barrett's esophagus with early neoplasia: early termination of a prospective series.

BACKGROUND: Cryotherapy is a relatively novel ablation modality for the endoscopic ablation of Barrett's esophagus (BE). Data on the use of pressurized carbon dioxide (CO2) gas for cryoablation are scarce. STUDY AIM: To determine the efficacy and safety of cryospray ablation using pressurized CO2 gas in the treatment of BE with early neoplasia. METHODS: In this prospective single center case series, we aimed to include 30 patients with BE and early neoplasia. Nodular neoplastic lesions were treated with endoscopic mucosal resection (EMR). Residual BE mucosa was treated with cryospray ablation every 4 weeks until the complete BE segment was eliminated or up to seven treatment sessions. If no reduction of the BE segment was observed after two subsequent treatment sessions, cryoablation was terminated. Patients were contacted at days 1 and 4 post-treatment to evaluate the level of discomfort. Endoscopic and histologic follow-up evaluations were performed up to 24 months post-treatment. RESULTS: After the inclusion of 10 patients, insufficient effect of cryoablation was observed, resulting in early termination of the study. In total, seven patients with intramucosal carcinoma (IMC) and three with high grade dysplasia (HGD) were included. Prior EMR was performed in nine patients. A median of 2.5 (IQR 2.0 - 4.0) cryoablation sessions were performed. At 6 months of follow-up, complete eradication of intestinal metaplasia was observed in 11 % (1 /9; one patient died, not treatment or disease related) of the patients and complete eradication of dysplasia in 44 % (4 /9). In three patients, HGD or IMC was detected during follow-up, and was endoscopically treated. Apart from a gastric perforation as a result of gastric distension caused by CO2 gas during the first treatment, cryospray treatments were well tolerated. CONCLUSION: After a short learning curve, cryoablation using CO2 gas was found to be a safe and well tolerated treatment modality. However, in our experience, the efficacy of CO2 cryoablation combined with EMR for nodular lesions is disappointing for the treatment of BE associated neoplasia.

Risk of neoplastic progression in Barrett's esophagus diagnosed as indefinite for dysplasia: a nationwide cohort study.

BACKGROUND AND STUDY AIMS: A histological diagnosis of "indefinite for dysplasia" (IND) in Barrett's esophagus is used when a diagnosis of genuine dysplasia is equivocal. The aim of the present study was to assess the risk of progression to high grade dysplasia (HGD) or esophageal adenocarcinoma (EAC) after a diagnosis of IND in a nationwide cohort of patients with Barrett's esophagus. PATIENTS AND METHODS: Patients with a first diagnosis of IND in Barrett's esophagus between 2002 and 2011 were selected from a nationwide registry of histopathology diagnoses in The Netherlands. Patients were followed up until treatment for HGD, detection of EAC, or date of last endoscopy contact with biopsy sampling. RESULTS: In total, 1258 patients met the inclusion criteria, of whom 842 (66.9 %) underwent endoscopic follow-up. Patients were followed for a total of 2585 person-years (mean ± SD 3.01 ±â€Š2.6). Median duration until first follow-up endoscopy was 1.2 years (interquartile range 0.3 - 1.8 years). The progression rate from IND to the combined end point of HGD or EAC was 2.0 (95 % confidence interval [CI] 1.5 - 2.6) per 100 person-years and progression to EAC was 1.2 (95 %CI 0.8 - 1.6). After excluding cases with HGD or EAC within 1 year after IND diagnosis (n = 16), the progression rates were 1.4 (95 %CI 1.0 - 1.9) and 0.8 (95 %CI 0.5 - 1.2) per 100 person-years for HGD or EAC and EAC, respectively. CONCLUSION: In this large, population-based, cohort of patients with Barrett's esophagus, the incidence rate of HGD or EAC following a diagnosis of IND was 1.4 per 100 person-years. The results demonstrate the need for additional studies to select the subgroup of IND patients with an increased risk of neoplastic progression.

Surveillance of Barrett's esophagus and mortality from esophageal adenocarcinoma: a population-based cohort study.

OBJECTIVES: Barrett's esophagus (BE) is associated with an increased risk of developing esophageal adenocarcinoma (EAC). Patients with a known diagnosis of BE are usually advised to participate in an endoscopic surveillance program, but its clinical value is unproven. Our objective was to compare patients participating in a surveillance program for BE before EAC diagnosis with those not participating in such a program, and to determine predictive factors for mortality from EAC. METHODS: All patients diagnosed with EAC between 1999 and 2009 were identified in the nationwide Netherlands Cancer Registry. These data were linked to Pathologisch-Anatomisch Landelijk Geautomatiseerd Archief, the Dutch Pathology Registry. Prior surveillance was evaluated, and multivariable Cox proportional hazards regression analysis was performed to identify predictors for all-cause mortality at 2-year and 5-year follow-up. RESULTS: In total, 9,780 EAC patients were included. Of these, 791 (8%) patients were known with a prior diagnosis of BE, of which 452 (57%) patients participated in an adequate endoscopic surveillance program, 120 (15%) patients in an inadequate program, and 219 (28%) patients had a prior BE diagnosis without participating. Two-year (and five-year) mortality rates were lower in patients undergoing adequate surveillance (adjusted hazard ratio (HR)=0.79, 95% confidence interval (CI)=0.64-0.92) when compared with patients with a prior BE diagnosis who were not participating. Other factors associated with lower mortality from EAC were lower tumor stage (stage I vs. IV, HR=0.19, 95% CI=0.16-0.23) and combining surgery with neoadjuvant chemo/radiotherapy (HR=0.66, 95% CI=0.58-0.76). CONCLUSIONS: Participation in a surveillance program for BE, but only if adequately performed, reduces mortality from EAC. Nevertheless, it remains to be determined whether such a program is cost-effective, as more than 90% of all EAC patients were not known to have BE before diagnosis.

Familial clustering of Barrett's esophagus and esophageal adenocarcinoma in a European cohort.

BACKGROUND & AIMS: Up to 7% of cases of Barrett's esophagus (BE) or esophageal adenocarcinoma (EAC) in the United States occur in family clusters. We identified first-degree and second-degree relatives of patients with BE and EAC to determine the extent of familial clustering in a European cohort and studied differences between familial and nonfamilial cases. METHODS: A questionnaire was sent to all patients diagnosed with BE or EAC from 2000-2011 at 3 hospitals in the Netherlands (n = 838). Diagnoses of affected relatives were confirmed by using the Dutch Pathology Registry. Familial statuses of BE were defined as definitive (≥1 first-degree or second-degree relative with BE or EAC), possible (≥1 reported relative with BE or esophageal cancer without histologic confirmation), unlikely (no family history), or unknown. RESULTS: A total of 603 patients with BE or EAC (71%) responded and were included in the analysis. Familial BE was definitive for 7% of cases (n = 39, 10% of first-degree relatives affected), possible for 6% (n = 36), unlikely for 49% (n = 297), and unknown for 38% (n = 231). Definitive cases of familial BE were younger at onset of heartburn and EAC diagnosis; their first-degree relatives more frequently had reflux symptoms and a prior upper endoscopy, compared with unlikely cases of familial BE. CONCLUSIONS: In a database analysis of patients diagnosed with BE or EAC in the Netherlands, 7% of cases of BE and EAC were familial. These cases have a younger average age of onset of reflux symptoms and diagnosis of EAC than unlikely familial cases. These findings may indicate that genetic factors contribute to BE susceptibility, with a possible central role of gastroesophageal reflux.

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.

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

BACKGROUND: 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. METHODS: 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. RESULTS: 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. CONCLUSION: TLR4 activation in BE results in a strong increase in COX-2 and may contribute to malignant transformation.

microRNA-145 in Barrett's oesophagus: regulating BMP4 signalling via GATA6.

OBJECTIVE: Barrett's oesophagus (BE) is a metaplastic condition of the distal oesophagus which predisposes to oesophageal adenocarcinoma (EAC). It has been suggested that microRNAs (miRNAs) are involved in the process of development of BE and EAC; however, few functional miRNA data are available. The aim of the study was to perform a tissue-specific miRNA profile and, based on this, to examine the function of miRNA-145 in the oesophagus. DESIGN: miRNA expression profiling using microarray analysis in EAC, BE and normal squamous epithelium of the oesophagus (SQ) was performed and validated using real-time PCR in samples from 15 patients and in situ hybridisation in samples from 10 patients. The proliferative effect of miRNA-145 precursor transfection in the SQ (HET-1A) and BE cell line (BAR-T) was measured. Downstream targets of miRNA-145 were determined by analysing mRNA and protein expression from miRNA-145 transfected cells. RESULTS: Three unique miRNA expression profiles were found in tissue from EAC, BE and SQ, which showed that miRNA-145 was upregulated in BE compared with EAC and SQ. Overexpression of miRNA-145 in HET-1A and BAR-T cells reduced cell proliferation and inhibited GATA6, BMP4 and SOX9 mRNA expression. Furthermore, altered BMP4 signalling was observed in vitro on miRNA-145 overexpression. These effects were blocked when cells were co-transfected with a miRNA-145 specific inhibitor. Additionally, BMP4 incubation of HET-1A cells altered miRNA-145 and GATA6 expression over time. CONCLUSION: These results imply that miRNA-145 indirectly targets BMP4 via GATA6 and is potentially involved in the development of BE.

Common variants at the MHC locus and at chromosome 16q24.1 predispose to Barrett's esophagus.

Barrett's esophagus is an increasingly common disease that is strongly associated with reflux of stomach acid and usually a hiatus hernia, and it strongly predisposes to esophageal adenocarcinoma (EAC), a tumor with a very poor prognosis. We report the first genome-wide association study on Barrett's esophagus, comprising 1,852 UK cases and 5,172 UK controls in the discovery stage and 5,986 cases and 12,825 controls in the replication stage. Variants at two loci were associated with disease risk: chromosome 6p21, rs9257809 (Pcombined=4.09×10(-9); odds ratio (OR)=1.21, 95% confidence interval (CI)=1.13-1.28), within the major histocompatibility complex locus, and chromosome 16q24, rs9936833 (Pcombined=2.74×10(-10); OR=1.14, 95% CI=1.10-1.19), for which the closest protein-coding gene is FOXF1, which is implicated in esophageal development and structure. We found evidence that many common variants of small effect contribute to genetic susceptibility to Barrett's esophagus and that SNP alleles predisposing to obesity also increase risk for Barrett's esophagus.

Surveillance and follow-up strategies in patients with high-grade dysplasia in Barrett's esophagus: a Dutch population-based study.

OBJECTIVES: In patients with high-grade dysplasia (HGD) in Barrett's esophagus (BE), it is incompletely known which factors are associated with developing esophageal adenocarcinoma (EAC). We analyzed prior biopsy and follow-up strategies in a large nationwide population-based cohort of patients with HGD in BE, and identified predictors of EAC progression. METHODS: Prior biopsy records and follow-up evaluations were studied in patients with HGD in BE diagnosed between 1999 and 2008, using PALGA, a nationwide network and registry of histopathology and cytopathology in the Netherlands. Multivariate Cox proportional hazards regression analysis was performed to identify predictors for prevalent (≤ 6 months) and incident (> 6 months) EAC. RESULTS: In total, 827 patients with HGD in BE were included. Follow-up data after HGD diagnosis were available in 699 (85%) patients. In 249 (36%) of these patients, an EAC was detected (14.1 EACs per 100 person-years). The risk of prevalent EAC (n=177) was lower with previous surveillance (hazards ratio 0.7; 95% confidence interval 0.5-0.9), unifocal HGD (0.3;0.2-0.6), diagnosis in a university hospital (0.5;0.3-0.9), endoscopic resection (0.5;0.3-0.7), or ablation (0.0;0.0-0.3); and higher when patients were 65-75 years (1.5;1.04-2.04). After exclusion of prevalent EACs, the progression rate was 4.2 EACs per 100 person-years. The risk of progression to incident EAC (n = 72) was lower with previous surveillance (0.6;0.3-0.9) and ablation (0.2;0.0-0.8), and higher when > 75 years (3.8;2.0-7.2) or with an interval > 6 months between HGD diagnosis and first follow-up (e.g., 7-12 months 2.9;1.3-6.3). CONCLUSIONS: In this cohort of patients with HGD in BE, the EAC detection rate was 14.1 per 100 person-years and 4.2 per 100 person-years after excluding prevalent cases. The risk of both prevalent and incident EAC was reduced with previous surveillance and endoscopic treatment, while it was increased with older age.

Role and regulation of adipokines during zymosan-induced peritoneal inflammation in mice.

Adipokines, cytokines mainly produced by adipocytes, are active participants in the regulation of inflammation. Administration of zymosan (ZY) was used to investigate the regulation and role of adipokines during peritonitis in mice. Injection of ZY led to a significant increase in leptin levels in both serum and peritoneal lavage fluid, whereas a differential trend in local vs. systemic levels was observed for both resistin and adiponectin. The role of leptin in ZY-induced peritonitis was investigated using leptin-deficient ob/ob mice, with and without reconstitution with exogenous leptin. Leptin deficiency was associated with delayed resolution of peritoneal inflammation induced by ZY, because ob/ob mice had a more pronounced cellular infiltrate in the peritoneum as well as higher and prolonged local and systemic levels of IL-6, TNFalpha, IL-10, and chemokine (C-X-C motif) ligand 2 compared with wild-type mice. Reconstitution with exogenous leptin exacerbated the inflammatory infiltrate and systemic IL-6 levels in ob/ob mice while inhibiting production of TNFalpha, IL-10, and chemokine (C-X-C motif) ligand 2. In contrast with the important role of leptin in regulating each aspect of ZY-induced peritonitis, adiponectin deficiency was associated only with a decreased inflammatory infiltrate, without affecting cytokine levels. These findings point to a complex role for adipokines in ZY-induced peritonitis and further emphasize the interplay between obesity and inflammation.

A comparative analysis by SAGE of gene expression profiles of esophageal adenocarcinoma and esophageal squamous cell carcinoma.

Esophageal adenocarcinoma (EA) and esophageal squamous cell carcinoma (ESCC) are the two main types of esophageal cancer. Despite extensive research the exact molecular basis of these cancers is unclear. Therefore we evaluated the transcriptome of EA in comparison to non-dysplastic Barrett's esophagus (BE), the metaplastic epithelium that predisposes for EA, and compared the transcriptome of ESCC to normal esophageal squamous epithelium. For obtaining the transcriptomes tissue biopsies were used and serial analysis of gene expression (SAGE) was applied. Validation of results by RT-PCR and immunoblotting was performed using tissues of an additional 23 EA and ESCC patients. Over 58,000 tags were sequenced. Between EA and BE 1013, and between ESCC and normal squamous epithelium 1235 tags were significantly differentially expressed (p<0.05). The most up-regulated genes in EA compared to BE were SRY-box 4 and Lipocalin2, whereas the most down-regulated genes in EA were Trefoil factors and Annexin A10. The most up-regulated genes in ESCC compared to normal squamous epithelium were BMP4, E-Cadherin and TFF3. The results could suggest that the BE expression profile is closer related to normal squamous esophagus then to EA. In addition, several uniquely expressed genes are identified.

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.

An ex vivo readout for evaluation of dendritic cell-induced autologous cytotoxic T lymphocyte responses against esophageal cancer.

Esophageal cancer is a highly malignant disease that despite surgery and adjuvant therapies has an extremely poor outcome. Dendritic cell (DC) immunotherapy as a novel promising strategy could be an alternative for treating this malignancy. Effective DC-mediated immune responses can be achieved by raising cytotoxic T lymphocyte (CTL) response against multiple antigens through loading DCs with total tumor RNA. However, the efficacy of this strategy first needs to be evaluated in a pre-clinical setting. The aim of the study was to set up an ex vivo autologous human readout assay for assessing the effects of DC-mediated cytotoxic responses, using total tumor RNA as an antigen load. Biopsy specimens of seven esophageal cancer patients were used to establish primary cultures of normal and cancer cells and to obtain autologous RNA for loading DCs. Mature DCs loaded with either normal or tumor RNA were obtained and subsequently used to raise various lymphocytes populations. Apoptosis levels of the autologous cultures were measured before and after incubating the cultures with the different lymphocytes populations. The mean apoptosis levels in the tumor cell cultures, induced by lymphocytes instructed by DCs loaded with tumor RNA, significantly increased with 15.6% +/-2.9 SEM (range 3.4-24.5%, t-test, P < 0.05). Incubation of the normal cultures with the lymphocytes populations showed a mean non-significant increase in apoptosis of 0.4% +/-3.4 SEM (range -13.9 to 9.8%, t-test, P = 0.7). Here, we introduce a practical, patient-specific autologous readout assay for pre-clinical testing of DC-mediated cytotoxic responses. Additionally, we demonstrated that the use of autologous tumor RNA as a strategy for raising cytotoxic responses against multiple tumor antigens could be effective for treating esophageal cancer.

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.