Nationwide multicenter study on adverse events associated with a patency capsule: Additional survey of appropriate use of patency capsule study

BACKGROUND AND AIM

The PillCam patency capsule (PC) without a radio frequency identification tag was released to preclude retention of the small bowel capsule endoscope (CE) in Japan in 2012. We conducted a multicenter study to determine tag-less PC-related adverse events (AEs).

METHODS

We first conducted a retrospective survey using a standardized data collection sheet for the clinical characteristics of PC-related AEs among 1096 patients collected in a prospective survey conducted between January 2013 and May 2014 (Cohort 1). Next, we retrospectively investigated additional AEs that occurred before and after Cohort 1 within the period June 2012 and December 2014 among 1482 patients (Cohort 2).

RESULTS

Of the 2578 patients who underwent PC examinations from both cohorts, 74 AEs occurred among 61 patients (2.37%). The main AEs were residual parylene coating in 25 events (0.97%), PC-induced small bowel obstruction, suspicious of impaction, in 23 events (0.89%), and CE retention even after patency confirmation in 10 events (0.39%). Residual parylene coating was significantly associated with Crohn's disease (P < 0.01). Small bowel obstruction was significantly associated with physicians with less than 1 year of experience handling the PC and previous history of postprandial abdominal pain (P < 0.01 and P < 0.03, respectively). CE retention was ascribed to erroneous judgment of PC localization in all cases.

CONCLUSIONS

This large-scale multicenter study provides evidence supporting the safety and efficiency of a PC to preclude CE retention. Accurate PC localization in patients without excretion and confirmation of previous history of postprandial abdominal pain before PC examinations is warranted (UMIN000010513).

Background factors of idiopathic peptic ulcers and optimal treatment methods: a multicenter retrospective Japanese study

This study investigated the trends in idiopathic peptic ulcers, examined the characteristics of refractory idiopathic peptic ulcer, and identified the optimal treatment. The characteristics of 309 patients with idiopathic peptic ulcer were examined. We allocated idiopathic peptic ulcers that did not heal after 8 weeks' treatment (6 weeks for duodenal ulcers) to the refractory group and those that healed within this period to the healed group. The typical risk factors for idiopathic peptic ulcer (atherosclerosis-related underlying disease or liver cirrhosis complications) were absent in 46.6% of patients. Absence of gastric mucosal atrophy (refractory group: 51.4%, healed group: 28.4%; p = 0.016), and gastric fundic gland polyps (refractory group: 17.6%, healed group: 5.9%; p = 0.045) were significantly more common in the refractory group compared to the healed group. A history of H. pylori eradication (refractory group: 85.3%, healed group: 66.0%; p = 0.016), previous H. pylori infection (i.e., gastric mucosal atrophy or history of H. pylori eradication) (refractory group: 48.5%, healed group: 80.0%; p = 0.001), and potassium-competitive acid blocker treatment (refractory group: 28.6%, healed group, 64.1%; p = 0.001) were significantly more frequent in the healed group compared to the refractory group. Thus, acid hypersecretion may be a major factor underlying the refractoriness of idiopathic peptic ulcer.

Reduction of butyric acid-producing bacteria in the ileal mucosa-associated microbiota is associated with the history of abdominal surgery in patients with Crohn's disease

Fecal microbiota is a significant factor determining the cause, course, and prognosis of Crohn's disease (CD). However, the factors affecting mucosa-associated microbiota (MAM) remain unclear. This retrospective study examined the differences in ileal MAM between CD patients and healthy controls and investigated the factors affecting MAM in CD patients to clarify potential therapeutic targets. Ileal MAM was obtained using brush forceps during endoscopic examination from 23 healthy controls and 32 CD patients (most were in remission). The samples' microbiota was profiled using the Illumina MiSeq platform. Compared to controls, CD patients had significantly reduced α-diversity in the ileum and a difference in β-diversity. The abundance of butyric acid-producing bacteria in the ileal MAM was significantly lower in CD patients with a history of abdominal surgery than in those without. Because butyric acid is a major energy source in the intestinal epithelium, its metabolism via β-oxidation increases oxygen consumption in epithelial cells, reducing oxygen concentration in the intestinal lumen and increasing the abundance of obligate anaerobic bacteria. The suppression of obligate anaerobes in CD patients caused an overgrowth of facultative anaerobes. Summarily, reducing the abundance of butyric acid-producing bacteria in the ileal MAM may play an important role in CD pathophysiology.

Trajectory analyses to identify persistently low responders to COVID-19 vaccination in patients with inflammatory bowel disease: a prospective multicentre controlled study, J-COMBAT

BACKGROUND

The degree of immune response to COVID-19 vaccination in inflammatory bowel disease (IBD) patients based on actual changes in anti-SARS-CoV-2 antibody titres over time is unknown.

METHODS

Data were prospectively acquired at four predetermined time points before and after two vaccine doses in a multicentre observational controlled study. The primary outcome was humoral immune response and vaccination safety in IBD patients. We performed trajectory analysis to identify the degree of immune response and associated factors in IBD patients compared with controls.

RESULTS

Overall, 645 IBD patients and 199 control participants were analysed. At 3 months after the second vaccination, the seronegative proportions were 20.3% (combination of anti-tumour necrosis factor [TNF]α and thiopurine) and 70.0% (triple combination including steroids), despite that 80.0% receiving the triple combination therapy were seropositive at 4 weeks after the second vaccination. Trajectory analyses indicated three degrees of change in immune response over time in IBD patients: high (57.7%), medium (35.6%), and persistently low (6.7%). In the control group, there was only one degree, which corresponded with IBD high responders. Older age, combined anti-TNFα and thiopurine (odds ratio [OR], 37.68; 95% confidence interval [CI], 5.64-251.54), steroids (OR, 21.47; 95%CI, 5.47-84.26), and tofacitinib (OR, 10.66; 95%CI, 1.49-76.31) were factors associated with persistently low response. Allergy history (OR, 0.17; 95%CI, 0.04-0.68) was a negatively associated factor. Adverse reactions after the second vaccination were significantly fewer in IBD than controls (31.0% vs 59.8%; p < 0.001).

CONCLUSIONS

Most IBD patients showed a sufficient immune response to COVID-19 vaccination regardless of clinical factors. Assessment of changes over time is essential to optimize COVID-19 vaccination, especially in persistently low responders.

Astaxanthin attenuated the stress-induced intestinal motility disorder via altering the gut microbiota

Gut microbiota and short-chain fatty acids (SCFAs) are recognized as key factors in the pathophysiology of irritable bowel syndrome. Astaxanthin is a carotenoid with strong antioxidant and anti-inflammatory activities. In this study, we examined the effects of astaxanthin on gut microbiota-, SCFAs-, and corticotropin-releasing factor (CRH)-induced intestinal hypermotility. Male Wistar rats (n=12 per group) were fed a diet with or without 0. 02% (w/w) astaxanthin for four weeks and CRH or saline was administered intravenously. The number of fecal pellets was counted 2 h after injection. Then the rats were sacrificed, and the cecal content were collected 3 h after injection. The number of feces was significantly increased by CRH injection in the control group (2.0 vs. 6.5; p=0.028), but not in the astaxanthin group (1.0 vs. 2.2; p=0.229) (n=6 per group). The cecal microbiota in the astaxanthin group was significantly altered compared with that in the control group. The concentrations of acetic acid (81.1 μmol/g vs. 103.9 μmol/g; p=0.015) and butyric acid (13.4 μmol/g vs. 39.2 μmol/g; p<0.001) in the astaxanthin group were significantly lower than that in the control group (n=12 per group). Astaxanthin attenuates CRH-induced intestinal hypermotility and alters the composition of gut microbiota and SCFAs.

Serial Changes in Intestinal Stenotic Stiffness in Patients with Crohn's Disease Treated with Biologics: A Pilot Study Using Ultrasound Shear Wave Elastography

BACKGROUND/AIMS

Intestinal strictures represent an important serious complication of Crohn's disease. Shear wave elastography is a promising noninvasive ultrasound technique for assessing tissue stiffness. This study aimed to evaluate stiffness in the areas of intestinal stricture in patients with Crohn's disease using shear wave elastography and the changes in stiffness after biologics.

MATERIALS AND METHODS

We enrolled 21 Crohn's disease patients having intestinal stricture. The patients consisted of 3 groups, which were the infliximab naïve (n = 6) group, the ustekinumab naïve (n = 8), and the bio-switch from infliximab to ustekinumab (n = 7) group. Bowell wall thickness was examined by ultrasound sonography, and the stiffness of Crohn's disease stricture lesions was evaluated using Shear wave speed before and 1 year after anti-tumor necrosis factor-alpha antibody infliximab, anti-interleukin 12/23 antibody ustekinumab, and bio-switch from infliximab to ustekinumab.

RESULTS

Bowell wall thickness was significantly improved after infliximab, ustekinumab, and the bio-switch. However, shear wave speed indices only in the ustekinumab group significantly decreased after treatment (P = .028), but not in the other group.

CONCLUSIONS

Shear wave elastography might be a useful method to evaluate stiffness in the areas of intestinal stricture in patients with Crohn's disease treated with biologics. However, a prospective randomized study evaluating the development of obstruction after biological treatment is needed to validate the study findings.

Current Status of Diagnosis and Treatment of Colorectal Cancer in Asian Countries: A Questionnaire Survey

INTRODUCTION

Diagnostic and therapeutic methods for colorectal cancer (CRC) have advanced; however, they may be inaccessible worldwide, and their widespread use is challenging. This questionnaire survey investigates the current status of diagnosis and treatment of early-stage CRC in Asian countries.

METHODS

Responses to the questionnaire were obtained from 213 doctors at different institutions in 8 countries and regions. The questionnaire consisted of 39 questions on the following four topics: noninvasive diagnosis other than endoscopy (6 questions), diagnosis by magnification and image-enhanced endoscopy (IEE) including artificial intelligence (AI) (10 questions), endoscopic submucosal dissection (ESD), proper use among other therapeutic methods (11 questions), and pathologic diagnosis and surveillance (12 questions).

RESULTS

Although 101 of 213 respondents were affiliated with academic hospitals, there were disparities among countries and regions in the dissemination of advanced technologies, such as IEE, AI, and ESD. The NICE classification is widely used for the diagnosis of colorectal tumors using IEE, while the JNET classification with magnification was used in countries such as Japan (65/70, 92.9%) and China (16/22, 72.7%). Of the 211 respondents, 208 (98.6%) assumed that en bloc resection should be achieved for carcinomas, and 180 of 212 (84.9%) believed that ESD was the most suitable in cases with a diameter larger than 2 cm. However, colorectal ESD is not widespread in countries such as Thailand, the Philippines, and Indonesia.

CONCLUSION

The promotion of advanced technologies and education should be continual to enable more people to benefit from them.

Reduced abundance of butyric acid-producing bacteria in the ileal mucosa-associated microbiota of ulcerative colitis patients

Compositional changes in the microbiota are associated with various inflammatory diseases, including ulcerative colitis (UC). Aim: This study aimed to investigate the mucosa-associated microbiota (MAM) in patients with UC and its difference related with disease activity and classification. Brush samples were collected from the terminal ileum and sigmoid colon during endoscopic procedures. The microbiota of samples was profiled using the Illumina MiSeq platform. The V3-V4 regions of the gene encoding 16S rRNA (460 bp) were amplified using PCR. Fifty UC patients and twenty healthy controls were enrolled. UC patients displayed significantly reduced α-diversity in both the ileum and sigmoid colon compared to controls. A difference in β-diversity in the unweighted analysis was observed between the two groups. The abundance of Lactobacillus and Veillonella was significantly higher and that of Butyricicoccus, Ruminococcus and Lachnospiraceae was significantly lower in the ileum of UC patients than in controls. The abundance of Odoribacter in the ileum was significantly lower in left-sided colitis and pancolitis patients than in proctitis patients and lower in patients with highly severe disease activity than with mild disease activity. The reduction in abundance of butyric acid-producing bacteria, especially Odoribacter, in ileal MAM may play an important role in the pathophysiology of UC.

Safety and efficacy of capsule endoscopy for patients with newly diagnosed Crohn's disease: A multicenter retrospective study

Crohn's disease (CD) is a chronic inflammatory disease that develops at a young age and frequently leads to intestinal resection. Capsule endoscopy (CE) can directly and non-invasively inspect the entire small bowel mucosa. We suspected that CE could be a good diagnostic tool for detecting CD in young patients. The aim of this study was to investigate the safety and efficacy of CE in patients with newly diagnosed CD and to evaluate the CE findings, especially in the upper small bowel of young patients. We retrospectively investigated 32 patients with newly diagnosed CD from 5 institutions. Patient characteristics, clinical course, and characteristics of CE findings were analyzed. The total small intestine observation rate was 93%, and the retention rate was 3% (1/32). No abnormality was identified by ileocolonoscopy in 46% (15/32), and transition of small bowel lesions (TSL) was found in 35% (12/34) of the patients. The frequency of longitudinal ulcers and cobblestones in the upper small intestine was significantly higher in younger patients (≤20 years). Moreover, positive findings in the upper small intestine were predominantly observed in younger patients (≤20 years). CE for patients with newly diagnosed CD was safe and useful, especially for the detection of upper small bowel lesions in young patients.

Subepithelial Serotonin Reduces Small Intestinal Epithelial Cell Tightness via Reduction of Occluding Expression

BACKGROUND

The precise pathogenesis of irritable bowel syndrome (IBS) remains unresolved; however, recent studies have reported that patients with diarrhea-predominant IBS exhibit an increased small intestinal permeability and increased number of enterochromaffin cells containing high 5-hydroxytryptamine (5HT; serotonin) levels. In this study, we investigated whether 5HT has the potential to modulate small intestinal epithelial cell permeability, focusing on tight junction-associated proteins.

METHODS

The differentiated Caco-2 cell monolayer on porous filters (Millicell) was used. Then, 5HT was added to the lower Millicell compartment for 7 days. Intestinal epithelial cell permeability was assessed by measuring the flux of paracellular permeability markers. We further assessed the expression of occludin in the 5HT-stimulated Caco-2 monolayer.

RESULTS

We found that 5HT did not affect the viability of Caco-2 cells at concentrations up to 100 µM during the experimental period. Administration of 5HT to the basal side of Caco-2 cells increased the flux of 3H-labeled mannitol (182 Da) but did not increase that of FITC-dextran (4000 Da). Among the tight junction proteins, the expression of occludin was specifically decreased by stimulation with 5HT at a concentration of 100 µM.

CONCLUSION

In conclusion, excessive 5HT in the basal side increased the permeability of intestinal epithelial cells via reduction of occludin expression.

Evaluation of efficacy and safety of lubiprostone in patients with chronic constipation

OBJECTIVES

Lubiprostone is an apical type 2 chloride channel activator approved for the treatment of chronic constipation (CC), and nausea is the most common adverse symptom. However, the associated factors with the efficacy and the precise mechanism of nausea remain unclear. The aim of this study is to characterize clinical backgrounds related with the efficacy and the adverse symptoms of lubiprostone.

MATERIALS AND METHODS

Subjects were patients with CC who were prescribed lubiprostone from April 2017 to October 2019. The efficacy and safety of lubiprostone were retrospectively examined using the electronic medical record.

RESULTS

Hundred and fifty-five patients (76 men, and mean age 69) were evaluated. Lubiprostone was effective in 74 patients (47.8%), and the discontinuation due to adverse in 34 patients (21.9%). including nausea, diarrhea and abdominal pain in 16, 12 and 3 patients, respectively. The efficacy was significantly associated with gender, age, body mass index (BMI), diabetes mellitus, hypertension, calcium channel blockers and antipsychotics. In multivariate analysis, the efficacy was significantly associated with men (odds ratio [OR], 3.21; 95% confidence interval (CI), 1.42-7.27) and BMI (OR, 1.14; 95% CI, 1.02-1.28). The incidence of nausea was higher in patients under 65 years old, and hypertension was the significant protective factor for nausea.

CONCLUSIONS

Lubiprostone was effective for men patients with CC, and hypertension seems to be the protective factor for nausea.

Mucosa-Associated Microbiota in Patients with Irritable Bowel Syndrome: A Comparison of Subtypes

BACKGROUND

Most studies on gut microbiome of irritable bowel syndrome (IBS) have focused on fecal microbiota, instead of mucosa-associated microbiota (MAM).

AIMS

The aim of this study wasto investigate the MAM in IBS patients including the difference in subtypes of IBS, namely, diarrhea-predominant IBS (IBS-D) and constipation-predominant IBS (IBS-C).

METHODS

Endoscopic brush samples were taken from terminal ileum and sigmoid colon of patients with IBS (17 IBS-D patients and 7 IBS-C patients) and 10 healthy controls. The MAM of samples was profiled by 16S rRNA gene amplicon sequencing. Potential changes in the MAM at the functional level were evaluated using PICRUSt software and the KEGG database.

RESULTS

There were no differences in MAM composition between terminal ileum and sigmoid colon according to β-diversity based on the UniFrac distance. In view of α-diversity, Shannon (evenness) but not Chao1 (richness) or observed operational taxonomic units tended to be lower in sigmoid colon MAM of IBS-C and IBS-D than the control group. The abundance of 4 genera in the sigmoid colon and 7 genera in the terminal ileum was significantly different among the 3 groups. Linear discriminant analysis effect size (LEfSe) showed that the genera of Ruminococcus, Akkermansia, Butyrivibrio, Methylobacterium, and Microbacterium and the family Erysipelotrichaceae were significantly higher in the IBS-C group, and the abundance of the genera Streptococcus, Acidaminococcus, Butyricicoccus, and Parvimonas was significantly higher in the IBS-D group. In addition, the proportion of genes responsible for the secretion system and LPS biosynthesis was significantly higher and that for methane metabolism, lysine biosynthesis, and enzyme families was significantly lower in the IBS-D group than in the IBS-C group.

CONCLUSION

Dysbiosis pattern and the function of the microbiome seem to be different among subtypes of IBS, and MAM may play a crucial role in IBS symptom generation.

Diagnostic Ability of Magnifying Blue Light Imaging with a Light Emitting Diode Light Source for Early Gastric Cancer: A Prospective Comparative Study

INTRODUCTION

An innovative endoscopic system using 4-color light-emitting diodes (LED) was released between 2016 and 2017 in locations that had not approved laser endoscopes for use, including the United States and Europe.

OBJECTIVE

This study compared the diagnostic efficacy between magnifying blue light imaging with an LED light source (LED-BLI) and magnifying blue laser imaging with a laser light source (Laser-BLI) for early gastric cancer (EGC).

METHODS

In this prospective, single-center, noninferiority study, 80 gastric lesions were evaluated between January 2017 and July 2017. The magnifying findings of gastric lesions - including the demarcation line (DL), microvascular pattern (MVP), and microsurface pattern (MSP) - were evaluated using Laser-BLI and LED-BLI according to the vessel plus surface classification system (VSCS). The primary end point was to determine whether the diagnostic accuracy of LED-BLI for EGC was noninferior to that of conventional Laser-BLI.

RESULTS

Overall, we evaluated 79 gastric lesions histopathologically diagnosed as adenocarcinomas from the specimens obtained via endoscopic submucosal dissection. A DL was observed by Laser-BLI and LED-BLI in 98.7% (78/79) and 96.2% (76/79) of EGCs, respectively. The MVP observed using Laser-BLI and LED-BLI was irregular in 92.4% (73/79) and 89.9% (71/79), respectively. The MSP observed using Laser-BLI and LED-BLI was irregular in 83.5% (66/79) and 82.2% (65/79), respectively. According to the VSCS, diagnosable cancers were found in 94.9% (75/79) and 93.7% (74/79) of cases when using Laser-BLI and LED-BLI, respectively (p = 0.73; difference ratio, 1.2%; 95% CI -8.5 to 6.0%).

CONCLUSIONS

LED-BLI could accurately visualize the DL, MVP, and MSP of EGCs and was not inferior to Laser-BLI. Therefore, LED-BLI can be used to diagnose EGC accurately according to the VSCS-based diagnosis criteria.

PDZK1 induces resistance to apoptosis in esophageal adenocarcinoma cells

BACKGROUND

Esophageal cancer is a lethal malignancy with a poor prognosis. The incidence of esophageal adenocarcinoma, which develops from Barrett's esophagus (BE), has recently been increasing. In a previous study, we found that PDZK1 expression is higher in long segment BE compared to that in short-segment BE. However, the function of PDZK1 in the mucosa of BE is unclear.

AIMS

Clarify the role of PDZK1 in BE mucosa using PDZK1 overexpressed cells.

METHODS

Human adenocarcinoma-derived OE33 cells were used as a parental cell line and transfected to generate PDZK1 overexpressed OE33 cells (PC cells) or transfected with empty vector as control cells (NC cells). Cell growth of NC and PC cells in 10% fetal bovine serum was evaluated by cell counting. The effect of PDZK1 on proteasome inhibitor (PSI)-induced apoptosis was qualified by fluorescence microscopy and quantified by flow cytometry. Expression of apoptosis-related proteins was evaluated by western blotting.

RESULTS

There were no significant differences in cell growth between NC and PC cells. PSI significantly increased apoptosis in NC cells, but not in PC cells. In response to PSI, increased levels of cleaved-caspase3 and decreased pro-caspase3 levels were found in NC cells, but not in PC cells. In NC cells, PSI significantly decreased Bcl-2 expression without affecting Bax levels. In contrast, high expression of both Bcl-2 and Bax was observed in PC cells.

CONCLUSION

Overexpression of PDZK1 protein induces an apoptosis-resistant phenotype in BE cells, which may be a potential therapeutic target.

Partially hydrolyzed guar gum attenuates non-alcoholic fatty liver disease in mice through the gut-liver axis

BACKGROUND

The gut-liver axis has attracted much interest in the context of chronic liver disease pathogenesis. Prebiotics such as dietary fibers were shown to attenuate non-alcoholic fatty liver disease (NAFLD) by modulating gut microbiota. Partially hydrolyzed guar gum (PHGG), a water-soluble dietary fiber, has been reported to alleviate the symptoms of various intestinal diseases and metabolic syndromes. However, its effects on NAFLD remain to be fully elucidated.

AIM

To determine whether treatment with PHGG attenuates NAFLD development in mice through the gut-liver axis.

METHODS

Seven-week-old male C57BL/6J mice with increased intestinal permeability were fed a control or atherogenic (Ath) diet (a mouse model of NAFLD) for 8 wk, with or without 5% PHGG. Increased intestinal permeability was induced through chronic intermittent administration of low-dose dextran sulfate sodium. Body weight, liver weight, macroscopic findings in the liver, blood biochemistry [aspartate aminotransferase (AST) and alanine aminotransferase (ALT), total cholesterol, triglyceride, free fatty acids, and glucose levels], liver histology, myeloperoxidase activity in liver tissue, mRNA expression in the liver and intestine, serum endotoxin levels in the portal vein, intestinal permeability, and microbiota and short-chain fatty acid (SCFA) profiles in the cecal samples were investigated.

RESULTS

Mice with increased intestinal permeability subjected to the Ath diet showed significantly increased serum AST and ALT levels, liver fat accumulation, liver inflammatory (tumor necrosis factor-α and monocyte chemotactic protein-1) and fibrogenic (collagen 1a1 and α smooth muscle actin) marker levels, and liver myeloperoxidase activity, which were significantly attenuated by PHGG treatment. Furthermore, the Ath diet combined with increased intestinal permeability resulted in elevated portal endotoxin levels and activated toll-like receptor (TLR) 4 and TLR9 expression, confirming that intestinal permeability was significantly elevated, as observed by evaluating the lumen-to-blood clearance of fluorescein isothiocyanate-conjugated dextran. PHGG treatment did not affect fatty acid metabolism in the liver. However, it decreased lipopolysaccharide signaling through the gut-liver axis. In addition, it significantly increased the abundance of cecal Bacteroides and Clostridium subcluster XIVa. Treatment with PHGG markedly increased the levels of SCFAs, particularly, butyric acid, acetic acid, propionic acid, and formic acid, in the cecal samples.

CONCLUSION

PHGG partially prevented NAFLD development in mice through the gut-liver axis by modulating microbiota and downstream SCFA profiles.

Molecular biomarker identification for esophageal adenocarcinoma using endoscopic brushing and magnified endoscopy

BACKGROUND

Barrett's esophagus (BE) is a predisposing factor for esophageal adenocarcinoma (EAC); however, the precise mechanism underlying this association remains unclear. The identification of biomarkers that are associated with an increased risk of BE progression to EAC would facilitate diagnosis and early treatment. Toward this goal, we aimed to identify biomarkers associated with BE and EAC in patients.

METHODS

In conjunction with high-resolution magnified endoscopy with narrow-band imaging (ME-NBI), we obtained brushing samples from the long-segment BE (LSBE) or short-segment BE (SSBE) of patients with EAC or without EAC (control). To identify candidate biomarker genes, microarray analysis was performed for a training set of 28 American samples. To confirm the microarray results, expression levels of the 16 candidate biomarkers were evaluated by real-time polymerase chain reaction analysis, using samples collected from an additional 53 American patients. In addition, we also performed a functional analysis for these genes using Gene Ontology (GO) enrichment analysis.

RESULTS

Among the 16 genes identified as differentially expressed by microarray analysis, the GO analysis indicated matrix metalloproteinase (MMP) family associated with 'collagen metabolic process' and 'multicellular organismal macromolecule metabolic process' as the two top biological processes. Brushing samples of patients with EAC showed up-regulated expression of decay-accelerating factors (DAF and CD55) and topoisomerase type Iiα (TOP2A), and down-regulated expression of the sodium channel epithelial 1 beta subunit (SCNN1B).

CONCLUSIONS

The up-regulation of CD55 and TOP2A, and the down-regulation of SCNN1B were common to the brushing samples and might serve as molecular biomarkers for identifying EAC in patients with SSBE.

TRIAL REGISTRATION

University Hospital Medical Information Network (UMIN) (000004004).

P2Y12 Inhibitors Exacerbate Low-dose Aspirin-induced Small Bowel Injury in Dual Antiplatelet Therapy

Objective Antithrombotic drugs are being used increasingly frequently to prevent cardiovascular diseases. Few studies have evaluated small bowel mucosal injury induced by dual antiplatelet therapy (DAPT). The aim of the present study was to evaluate small bowel mucosal injury induced by DAPT compared with other antithrombotics using video capsule endoscopy (VCE). Methods The study included chronic users of antithrombotics who underwent VCE for obscure gastrointestinal bleeding between January 2007 and July 2018. We evaluated the instances of small bowel injury classified into erosions and ulcers. Results Overall, 183 patients (114 men and 69 women; mean age, 73.6 years old) were enrolled, and the study groups comprised 49 patients taking low-dose aspirin (LDA) only, 50 taking anticoagulants only, 37 being treated with DAPT, 33 on combined LDA and anticoagulants, and 14 taking P2Y12 inhibitors. Small bowel erosions and ulcers were most frequently observed in the DAPT group, with frequencies of 78.4% and 37.8%, respectively. Exacerbating factors of small bowel ulcers were DAPT [odds ratio (OR) 3.0, 95% confidence interval (CI) 1.2-7.7] and age over 80 years old (OR 2.4, 95% CI 1.1-5.4). Conclusion P2Y12 inhibitors seem to exacerbate LDA-induced small bowel injury. Preventive strategies for small bowel injury induced by LDA, especially DAPT, are urgently required.

Comparison of mucosa-associated microbiota in Crohn’s disease patients with and without anti-tumor necrosis factor-α therapy

Most studies on the gut microbiome of Crohn’s disease have been conducted using feces, instead of intestinal mucus to analyze the mucosa-associated microbiota. To investigate the characteristics of mucosa-associated microbiota in Crohn’s disease patients and the effect of anti-tumor necrosis factor (TNF)-α therapy on mucosa-associated microbiota, we analyzed microbiota in Crohn’s disease patients using brushing samples taken from terminal ileum. The recruited subjects were 18 Crohn’s disease patients and 13 controls. There were 10 patients with anti-TNF-α therapy in Crohn’s disease group. Crohn’s disease patients had significantly reduced α-diversity in Shannon index compared to the controls. The comparative analysis of the taxonomic composition at the genus level between the Crohn’s disease group and the controls indicated that butyrate-producing bacteria were less abundant in the Crohn’s disease group compared to the controls. There were no differences in the diversity between the patients taking anti-TNF-α therapy and the patients without. The comparative analysis of the taxonomic composition at the genus level between the two groups indicated that some of anti-inflammatory bacteria were less abundant in the anti-TNF-α therapy group than the other. Reduction of specific bacteria producing anti-inflammatory molecules, especially butyrate-producing bacteria may play important roles in the pathophysiology of Crohn’s disease.

Mucosa-Associated Microbiota in the Gastrointestinal Tract of Healthy Japanese Subjects

BACKGROUND

The importance of microbiota infiltrating the gut mucus layer has been reported in the pathogenesis of various gastrointestinal and systemic diseases. However, little is known about the mucosa-associated microbiota (MAM) in healthy subjects. The present study aimed to clarify the characteristics of the gastrointestinal MAM from the oral cavity to the rectum in healthy Japanese subjects.

METHODS

Seventeen healthy subjects were enrolled. In this study, 5 mucosa samples from the upper gut (intraoral, mid-esophagus, gastric corpus, gastric antrum, and duodenum) and 7 from the lower gut (ileum, cecum, ascending colon, transverse colon, descending colon, sigmoid colon, and rectum) were collected with a brush under endoscopic examination. MAM profiles of each sample were analyzed by 16S-rRNA V3-V4 gene sequences.

RESULTS

Collecting mucosa samples by brushing provided sufficient material for MAM profiling without causing adverse effects. The upper and lower gut MAM profiles differed significantly (p < 0.0001). In the upper and lower gut, the intra- and inter-individual MAM profiles were significantly different (p = 0.0008 and p < 0.0001 respectively).

CONCLUSIONS

The MAM profiles of the upper and lower gut were significantly different. The inter-individual differences in MAM were remarkable compared to the intra-individual differences.

Effectiveness of including probiotics to Helicobacter pylori eradication therapies

The eradication rate of Helicobacter pylori (H. pylori) with proton pump inhibitors, amoxicillin, and clarithromycin has reportedly decreased. Some studies have found probiotics to be useful in eradicating H. pylori, but these effects have not been sufficiently investigated. We aimed to elucidate the role of probiotics in eradicating H. pylori infection. Patients in our hospital with H. pylori infection that received standard treatment from January 2015 to December 2016 were retrospectively evaluated (n = 468). They were divided into three groups based on their treatment regime, being either proton pump inhibitors, amoxicillin, or clarithromycin (PPI group), vonoprazan, amoxicillin, or clarithromycin (VPZ group), and proton pump inhibitors, amoxicillin, or clarithromycin/probiotics (Miya-BM^®) (PPI + MBM group). We retrospectively evaluated the H. pylori eradication rate and reported side effects. According to intention-to-treat analyses, the eradication rate of H. pylori was significantly higher in the PPI + MBM group (87.1%) than in the PPI group (70.1%). There was no difference in side effects between any of the three groups. In conclusion, Miya-BM^® may have an additive effect when included with eradication therapies for H. pylori.

Higher Levels of Streptococcus in Upper Gastrointestinal Mucosa Associated with Symptoms in Patients with Functional Dyspepsia

BACKGROUND

Functional dyspepsia (FD) is associated with poor health-related quality of life. Recent evidence suggests that the main pathogenesis suspect is the gut mucosa-associated microbiota (MAM). However, little is known about the MAM in FD subjects. The aim of this study was to clarify the relationship between upper gastrointestinal symptoms in FD and the characteristics of the gastrointestinal MAM.

SUMMARY

Five mucosa samples from the upper gut (intraoral, mid-esophagus, gastric body, gastric antrum, and descending portion of the duodenum) were collected with a brush under endoscopic examination from FD and healthy control subjects. MAM profiles of each sample were analyzed by 16S-rRNA -V3-V4 gene sequences. Questionnaire was used to assess gastrointestinal symptoms in FD. Between FD and healthy control subjects, although the comparison of MAM α-diversity showed no significant differences, the structure of MAM (β-diversity) was clearly different. Only the phylum Firmicutes was increased in FD compared to healthy control subjects in all sites of the upper gut. At the genus level, Streptococcus was significantly increased in all sites in the upper gut in FD. The relative abundance of Streptococcus was positively correlated with upper gastrointestinal symptoms in each upper gut group. Furthermore, the relative abundance of OTU 90 was positively correlated with upper gastrointestinal symptoms in all sites in the upper gut in FD. Key Messages: Streptococcus is a bacterium strongly correlated with upper gastrointestinal symptoms in FD.

High-Fat Diet Causes Constipation in Mice via Decreasing Colonic Mucus

BACKGROUND

Constipation is one of the most common gastrointestinal complaints. Although the causes of constipation are varied, dietary habits have a significant influence. Excessive fat intake is suggested as one of the main causes of constipation; however, the exact mechanism is unknown.

AIMS

To investigate whether a high-fat diet (HFD) causes constipation in mice and to clarify the underlying mechanism, focusing on the amount of colonic mucus.

METHODS

Six-week-old male C57BL/6 mice were randomly divided into two groups: mice fed with HFD and those with normal chow diet (NCD). Fecal weight, water content, total gastrointestinal transit time, and colon transit time were measured to determine whether the mice were constipated. The colonic mucus was evaluated by immunostaining and quantified by spectrometry. Malondialdehyde (MDA) was measured using the thiobarbituric acid (TBA) test as a marker for oxidative stress.

RESULTS

Compared to the NCD group, the weight of feces was less in the HFD group. In the functional experiment, the total gastrointestinal transit time and colon transit time were longer in the HFD group. Furthermore, HFD significantly reduced the amount of colonic mucus. In addition, the reduction in colonic mucus caused by surfactant resulted in constipation in the NCD group.

CONCLUSIONS

HFD causes constipation with delayed colon transit time possibly via the reduction in colonic mucus in mice.

Helicobacter pylori eradication therapy outcome according to clarithromycin susceptibility testing in Japan

BACKGROUND

Helicobacter pylori (Hp) infection increases the risk of gastric cancer. Therefore, eradication is a global goal, which requires continuous monitoring of therapeutic regimens and effectiveness. Clarithromycin resistance is an important contributor to eradication failure, and metronidazole is recommended as second-line treatment in such cases. Here, we retrospectively evaluated the clarithromycin and metronidazole resistance rates and treatment effectiveness in patients with Hp using tailored therapies according to clarithromycin susceptibility testing.

METHODS

Data on drug susceptibility were obtained for 5249 Japanese Hp patients between July 2005 and August 2018. Clarithromycin/metronidazole resistance rates were analyzed according to year, gender, and age with Fisher's exact test. The relationship between clarithromycin resistance and Hp therapy outcomes was assessed for 1300 patients. Treatment regimens included a clarithromycin- or metronidazole-containing 7-day triple therapy with one of several proton pump inhibitors and vonoprazan.

RESULTS

Clarithromycin resistance increased annually and was higher in women and younger patients (<30 years). Rates of metronidazole resistance were stable but decreased with age. Hp treatment regimens using PPIs had eradication rates of 88% and 45% among clarithromycin-sensitive and clarithromycin-resistant cases, respectively, while regimens including vonoprazan had eradication rates of around 90% regardless of clarithromycin susceptibility. In particular, triple therapy with vonoprazan, amoxicillin, and metronidazole achieved 98% eradication.

CONCLUSION

Clarithromycin-containing triple therapy even using vonoprazan did not achieve satisfactory eradication rates even in the clarithromycin-sensitive group. To avoid antibiotic misuse in population with low metronidazole resistance, 7-day vonoprazan, amoxicillin, and metronidazole triple therapy might be a strong candidate as a first-line eradication therapy.

Efficacy and Feasibility of Magnifying Blue Laser Imaging without Biopsy Confirmation for the Diagnosis of the Demarcation of Gastric Tumors: A Randomized Controlled Study

BACKGROUND

Accurate diagnosis of the demarcation line (DL) of gastric tumors is essential for curative complete resection by endoscopic submucosal dissection (ESD). It is controversial to perform only magnifying endoscopy for diagnosing the DL of gastric tumors prior to ESD. This study aimed to evaluate the diagnostic accuracy for the DL of gastric adenomas and well-differentiated adenocarcinomas using only magnifying blue laser imaging (M-BLI) compared with that using both M-BLI and biopsy confirmation.

METHODS

In this prospective, single-center study, 96 well-differentiated adenocarcinomas and 32 gastric adenomas were enrolled between July 2015 and December 2016. A total of 122 lesions with a clear DL on M-BLI were randomly allocated to undergo M-BLI only (the M-BLI group) or M-BLI with biopsy confirmation (the M-BLI-BC group), performed as biopsies in 4 directions from noncancerous tissues ≈ 5 mm outside the lesion before ESD. The primary end point was to clarify the noninferiority of M-BLI without biopsy confirmation compared with that with biopsy confirmation, in terms of the diagnostic accuracy and complete resection.

RESULTS

There were no significant differences in sex, median age, color, circumference, macroscopic type, biopsy-based diagnosis, and Helicobacter pylori infection between the 2 groups. The diagnostic accuracy for the DL was 100 and 95.0% and the complete resection was 100 and 100% in the M-BLI and M-BLI-BC groups, respectively.

CONCLUSION

The diagnostic ability of M-BLI is excellent in diagnosing the demarcation of gastric adenoma and well-differentiated adenocarcinoma. Biopsy confirmation is not needed for these lesions with a clear DL by M-BLI.

Nutrients and probiotics: current trends in their use to eradicate Helicobacter pylori

Helicobacter pylori is a well-known bacterium that infects the human gastric mucosa and causes gastric inflammation, ultimately resulting in gastric cancer. To reduce the incidence of gastric cancer, eradication therapy is important. However, the rate of successful eradication gradually decreases due to increased antibiotic resistance to Helicobacter pylori. In order to increase the eradication rate and reduce gastric cancer incidence, food factors or probiotics are expected to play a beneficial role. Although several foods have been reported to inhibit bacterial load and gastric inflammation, further assessment on large population prospective studies in this field is warranted. Several food compounds, including phytochemicals, are reported to suppress the incidence of gastric cancer. Future evaluations should consider differences in geographic factors. Probiotics are effective and safe for use in Helicobacter pylori eradication therapy.

Promotion of wound healing by acetate in murine colonic epithelial cell via c-Jun N-terminal kinase activation

BACKGROUND AND AIM

Mucosal healing is an important clinical goal in patients with inflammatory bowel disease. Recently, short-chain fatty acids (SCFAs) have been reported to have multifaceted effects to host. However, the effects of SCFAs on wound healing in intestinal epithelial cells are unclear. In the present study, we investigated the effects of acetate, one of the major SCFAs, on the wound healing of murine colonic epithelial cells.

METHODS

Young adult mouse colonic epithelial cells were used to determine the effect of acetate using wound healing assay. Mitogen-activated protein kinase and Rho kinase inhibitor were used to elucidate intracellular signal of wound healing treated with acetate. Meanwhile, Rho activation assays were utilized to measure Rho activation levels. To assess in vivo effects, C57B6 mice with dextran sodium sulfate for 7 days were treated with enema administration of acetate for 7 days. Body weight, disease activity index, colon length, and mucosal break ratio in histology were examined.

RESULTS

Acetate enhanced wound healing and fluorescence intensity of actin stress fiber compared with control. These effects were canceled with pretreatment of c-Jun N-terminal kinase (JNK) inhibitor or Rho kinase inhibitor. Furthermore, JNK inhibitor reduced the activation of Rho induced by acetate. In the dextran sodium sulfate-induced colitis model, the mice with enema treatment of acetate significantly exhibited recovery.

CONCLUSIONS

In this study, we demonstrated that acetate promoted murine colonic epithelial cell wound healing via activation of JNK and Rho signaling pathways. These findings suggested that acetate could have applications as a therapeutic agent for patients with intestinal mucosal damage, such as inflammatory bowel disease.

Effectiveness of including probiotics to Helicobacter pylori eradication therapies

The eradication rate of Helicobacter pylori (H. pylori) with proton pump inhibitors, amoxicillin, and clarithromycin has reportedly decreased. Some studies have found probiotics to be useful in eradicating H. pylori, but these effects have not been sufficiently investigated. We aimed to elucidate the role of probiotics in eradicating H. pylori infection. Patients in our hospital with H. pylori infection that received standard treatment from January 2015 to December 2016 were retrospectively evaluated (n = 468). They were divided into three groups based on their treatment regime, being either proton pump inhibitors, amoxicillin, or clarithromycin (PPI group), vonoprazan, amoxicillin, or clarithromycin (VPZ group), and proton pump inhibitors, amoxicillin, or clarithromycin/probiotics (Miya-BM^®) (PPI + MBM group). We retrospectively evaluated the H. pylori eradication rate and reported side effects. According to intention-to-treat analyses, the eradication rate of H. pylori was significantly higher in the PPI + MBM group (87.1%) than in the PPI group (70.1%). There was no difference in side effects between any of the three groups. In conclusion, Miya-BM^® may have an additive effect when included with eradication therapies for H. pylori.

Efficacy of Magnifying Narrow Band Imaging for Delineating Horizontal Margins of Early Gastric Cancer

BACKGROUND/AIMS

The aim of this study was to evaluate the diagnostic accuracy of magnifying narrow-band imaging (M-NBI) with histopathological confirmation in identifying the demarcation line (DL) of early gastric cancer (EGC).

METHODS

EGCs resected by endoscopic submucosal dissection after identifying the DL using M-NBI following histopathological confirmation were included. After determining the DL for the entire EGC lesion using M-NBI, at least 4 biopsies were taken from non-cancerous tissues outside the EGC lesion for histopathological confirmation.

RESULTS

A total of 330 EGCs were analyzed in this study. The rate of biopsy-negative and negative horizontal margin were 96.7% (319/330) and 97.9% (323/330) in EGC respectively. Tumors larger than 20 mm showed a higher risk for showing remnant cancer cells on biopsies taken outside the DL. Risk factors for a positive horizontal resection margin were tumor size > 20 mm and moderately or poorly differentiated adenocarcinomas.

CONCLUSION

The assessment of demarcation of EGC using M-NBI was excellent in well-differentiated (WD) adenocarcinoma and lesions below 20 mm in size. However, histopathological confirmation is needed to assess the demarcation of non-WD adenocarcinomas and EGC over 20 mm in size.

Clinical and Pathological Challenges in the Diagnosis of Gastric-Type Differentiated Adenocarcinoma in the Stomach: A Study of Endoscopic Submucosal Dissection Cases

BACKGROUND/AIMS

Gastric-type differentiated adenocarcinoma (GDA) of the stomach is a rare variant of gastric cancer that is highly infiltrating and exhibits early metastasis. However, the endoscopic and pathological features of "early-stage" GDA remain unknown. The aim of this study is to characterize early-stage GDA.

METHODS

We retrospectively enrolled 479 differentiated-type early gastric cancer cases who underwent endoscopic submucosal dissection (ESD). GDA cases were selected based on morphology and immunohistochemistry. Clinicopathological data were compared between gastric- and intestinal-type differentiated adenocarcinomas (IDAs).

RESULTS

Thirteen lesions were classified as GDAs. GDAs as well as IDAs showed irregular microvascular and microsurface patterns with clear demarcation line on magnifying endoscopy with narrow band imaging (M-NBI). The rate of pathological misdiagnosis of GDAs in biopsy specimens was higher than that of IDAs (p = 0.016). GDA was significantly associated with positive lymphovascular invasion (p = 0.016). There was one intramucosal lesion with lymphatic invasion in GDA.

CONCLUSIONS

Although M-NBI is useful to detect GDA, the pathological diagnosis of GDAs in biopsy specimens often remains challenging. When suspicious lesions are not diagnosed as GDA, they should be followed up intensively, or diagnostic ESD has to be performed. ESD specimens should be carefully evaluated because of a higher incidence of lymphovascular invasion.

Linked color imaging identifies important risk factors associated with gastric cancer after successful eradication of Helicobacter pylori

BACKGROUND AND AIMS

Limited studies have evaluated the risk factors of gastric cancer (GC) after eradication of Helicobacter pylori (H pylori) using endoscopic findings. We aimed to investigate GC detection-related endoscopic findings after eradication of H pylori using linked color imaging (LCI), a novel image-enhanced endoscopy.

METHODS

This single-center, cross-sectional study evaluated background mucosa-associated endoscopic findings described in the Kyoto classification of gastritis in patients with newly detected GC after eradication of H pylori (CA group, n = 109) and those without GC (NC group, n = 85) using white-light imaging (WLI) and LCI.

RESULTS

Severe atrophy and map-like redness were significantly more frequent in the CA group than in the NC group using WLI (79.8% vs 63.5%, P = .01; 61.5% vs 37.7%, P = .001, respectively) and LCI (79.8% vs 63.5%, P = .01; 78.0% vs 45.9%, P < .0001, respectively). Regular arrangement of collecting venules (RAC) was significantly less frequent in the CA group than in the NC group using WLI (40.3% vs 64.7%, P = .0009) and LCI (37.6% vs 62.4%, P = .0006). Map-like redness was an independent positive risk factor (WLI: odds ratio [OR], 2.05; 95% confidence interval [CI], 1.09-3.87; P = .03; LCI: OR, 3.62; 95% CI, 1.88-6.97; P < .001), whereas RAC was an independent negative risk factor (WLI: OR, 0.42; 95% CI, 0.21-0.82; P = .01; LCI: OR, 0.46; 95% CI, 0.23-0.93, P = .03) for detection of GC after eradication of H pylori.

CONCLUSIONS

Map-like redness, which was identified more frequently using LCI than WLI, and the absence of RAC were associated with detection of GC after eradication of H pylori.

Guidelines for the management of Helicobacter pylori infection in Japan: 2016 Revised Edition

BACKGROUND

Since "Helicobacter pylori (H. pylori) infection" was set as the indication in the Japanese Society for Helicobacter Research (JSHR) Guidelines 2009, eradication treatment for H. pylori gastritis is covered under insurance since 2013 in Japan, and the number of H. pylori eradication has rapidly increased. Under such circumstances, JSHR has made the third revision to the "Guidelines for diagnosis and treatment of H. pylori infection" for the first time in 7 years.

METHODS

The Guideline Committee held 10 meetings. Articles published between the establishment of the 2009 Guidelines and March 2016 were reviewed and classified according to the evidence level; the statements were revised on the basis of this review. After inviting public comments, the revised statements were finalized using the Delphi method.

RESULTS

There was no change in the basic policy that H. pylori infectious disease is an indication for eradication. Other diseases presumed to be associated with H. pylori infection were added as indications. Serum pepsinogen level, endoscopic examination, and X-ray examination were added to the diagnostic methods. The effects of 1-week triple therapy consisting of potassium-competitive acid blocker (P-CAB), amoxicillin, and clarithromycin have improved, and high eradication rates can also be expected with proton pump inhibitors (PPI) or P-CAB combined with amoxicillin and metronidazole. If the susceptibility test is not performed, the triple PPI or P-CAB/amoxicillin/metronidazole therapy should be chosen, because the PPI/amoxicillin/metronidazole combination demonstrated a significantly higher eradication rate than PPI/amoxicillin/clarithromycin. In the proposal for gastric cancer prevention, we divided gastric cancer prevention measures by age from adolescent to elderly, who are at an increased gastric cancer risk, and presented measures for gastric cancer prevention primarily based on H. pylori eradication.

CONCLUSION

We expect the revised guidelines to facilitate appropriate interventions for patients with H. pylori infection and accomplish its eradication and prevention of gastric cancer.

Self-study of the non-extension sign in an e-learning program improves diagnostic accuracy of invasion depth of early gastric cancer

Background and study aims  We developed an e-learning program for endoscopic diagnosis of invasion depth of early gastric cancer (EGC) using a simple diagnostic criterion called non-extension sign, and the contribution of self-study quizzes to improvement of diagnostic accuracy was evaluated. Methods  We conducted a prospective randomized controlled study that recruited endoscopists throughout Japan. After completing a pretest, the participants watched video lectures and undertook post-test 1. The participants were then randomly allocated to either the self-study or non-self-study group, and participants in the first group completed the self-study program that comprised 100-case quizzes. Finally, participants in both groups undertook post-test 2. The primary endpoint was the difference in post-test 2 scores between the groups. The perfect score for the tests was set as 100 points. Results  A total of 423 endoscopists completed the pretest and were enrolled. Post-test 1 was completed by 415 endoscopists and 208 were allocated to the self-study group and 207 to the non-self-study group. Two hundred and four in the self-study group and 205 in the non-self-study group were included in the analysis. Video lectures improved the mean score of post-test 1 from 72 to 77 points. Participants who completed the self-study quizzes showed significantly better post-test 2 scores compared with the non-self-study group (80 vs. 76 points, respectively, P  < 0.0001). Conclusions  Our e-learning program showed that self-study quizzes consolidated knowledge of the non-extension sign and improved diagnostic ability of endoscopists for invasion depth of EGC.

Ginsenoside Rb1 promotes intestinal epithelial wound healing through extracellular signal-regulated kinase and Rho signaling

BACKGROUND AND AIM

Daikenchuto, a traditional Japanese herbal medicine, has been reported to exhibit anti-inflammatory effects against intestinal inflammation. However, whether daikenchuto has a therapeutic effect against intestinal mucosal injuries remains unclear. Thus, the aim of this study was to determine the effect of daikenchuto on intestinal mucosal healing.

METHODS

Colitis was induced in male Wistar rats by using trinitrobenzenesulfonic acid. Daikenchuto (900 mg/kg/day) was administered for 7 days after the induction of colitis. Thereafter, intestinal mucosal injuries were evaluated by determining the colonic epithelial regeneration ratio ([area of epithelial regeneration/area of ulcer] × 100). Restoration of rat intestinal epithelial cells treated with daikenchuto and its constituent herbs (Zanthoxylum fruit, processed ginger, and ginseng) and ginsenoside Rb1, which is a ginseng ingredient, was evaluated using a wound-healing assay.

RESULTS

The colon epithelial regeneration ratio in the daikenchuto-treated rats was significantly higher than that in the control rats. Daikenchuto, ginseng, and ginsenoside Rb1 enhanced wound healing, and the ginsenoside Rb1-induced enhancement was inhibited by extracellular signal-regulated kinase and Rho inhibitors.

CONCLUSIONS

Daikenchuto and its constituent, ginsenoside Rb1, promoted wound healing. Because mucosal healing is one of the most important therapeutic targets in patients with inflammatory bowel disease, ginsenoside Rb1 may be a novel therapeutic agent against intestinal mucosal damage such as that occurring in intestinal bowel disease.

The Adjuvant Effect of Squalene, an Active Ingredient of Functional Foods, on Doxorubicin-Treated Allograft Mice

Many functional foods or physiologically active ingredients derived from plants and animals are actively being investigated for their role in chronic disease prevention. Squalene (SQ) is found as active ingredient in the functional foods predominantly present in olive oil and shark liver oil. It is known that during chemotherapy anticancer drugs induce inflammation. SQ has been thought to prevent and suppress inflammation; however, there is little direct evidence available. We examined the adjuvant effect of SQ on tumor-transplanted mice along with anticancer drug doxorubicin (DOX). SQ significantly suppressed the DOX-induced increase in prostaglandin E₂ (PGE₂) concentration (P < 0.05) in plasma of tumor-bearing mice. SQ inhibited the numbers of writhing response (P < 0.05), formalin-induced pain and decreased COX-2 and substance P expression in the tumor tissue compared to control mice and also enhanced the antitumor efficacy of DOX in allograft mice. Thus, SQ reduces inflammation through modulation of PGE₂ production indicating its potential as an adjuvant during chemotherapy in tumor-bearing mice.

[Impact of Primary Prophylaxis with Pegfilgrastim on Clinical Outcomes in Patients with Advanced Esophageal Cancer Receiving Chemotherapy with Docetaxel, Cisplatin ,and 5-FU]

It has been reported that docetaxel, cisplatin, and 5-FU combination chemotherapy(DCF)is effective for advanced esophageal cancer. However, we often encounter severe hematotoxicity during DCF therapy. Here, we retrospectively analyzed the data of patients with advanced esophageal cancer treated with DCF at our department, and assessed the efficacy of pegfilgrastim and the issues associated with its use. According to the results, pegfilgrastim may reduce the severe hematotoxicity associated with DCF therapy and may contribute to the maintenance of the intensity of DCF. However, neutropenia had already occurred before pegfilgrastim administration on day 7 in most patients. Therefore, the appropriate timing of pegfilgrastim administration in DCF must be determined in a future prospective study.

Heme oxygenase-1 prevents murine intestinal inflammation

Heme oxygenases (HOs) are rate-limiting enzymes catabolizing heme to biliverdin, ferrous iron, and carbon monoxide, and of the three HO isoforms identified, HO-1 plays a protective role against inflammatory processes. In this study, we investigated the possible role of HO-1 in intestinal inflammation. Acute colitis was induced in male C57BL/6 (wild-type) and homozygous BTB and CNC homolog 1 (Bach1)-deficient mice, which show high HO-1 expression in the colonic mucosa, using dextran sodium sulfate. The disease activity index, myeloperoxidase activity, and inflammatory cytokines in the colonic mucosa were evaluated 7 days after dextran sodium sulfate-dependent colitis induction. We also evaluated the impact of HO-1 inhibition using zinc protoporphyrin IX (25 mg/kg i.p., daily). After dextran sodium sulfate administration, HO-1 mRNA and protein expression increased in a time-dependent manner. Disease activity index score, myeloperoxidase activity, and colonic production of TNF-α and IFN-γ were increased after dextran sodium sulfate administration, and co-administration of zinc protoporphyrin IX enhanced their increase. In addition, disease activity index in Bach1-deficient was significantly lower after dextran sodium sulfate administration than that in wild type mice. These results indicate that HO-1 plays a protective role against dextran sodium sulfate-induced intestinal inflammation, possibly by regulating pro-inflammatory cytokines in intestinal tissues.

Transforming growth factor β1-induced collagen production in myofibroblasts is mediated by reactive oxygen species derived from NADPH oxidase 4

Intestinal fibrosis with stricture formation is a severe complication of Crohn's disease (CD). Though new therapeutic targets to enable the prevention or treatment of intestinal fibrosis are needed, markers of this condition and the basic mechanisms responsible have not been established. NADPH oxidase (NOX) 4 has already been reported to play a key role in models of fibrogenesis, including that of the lung. However, its importance in intestinal fibrogenesis remains unclear. In this study, we examined the role of NOX4 in collagen production by intestinal myofibroblasts stimulated with transforming growth factor (TGF)-β1. Using LmcMF cells, an intestinal subepithelial myofibroblast (ISEMF) line, we first examined the induction of collagen production by TGF-β1. Subsequently, we investigated the role of NOX4 in TGF-β1-induced collagen I production in these cells using SB525334 (an SMAD2/3 inhibitor), diphenyleneiodonium (an NOX inhibitor), and Nox4 small interfering RNA (siRNA). Production of collagen was assessed with Sirius red staining, and Nox4 expression was measured by quantitative real-time PCR. Reactive oxygen species (ROS) production was determined using DCFDA and fluorescent microscopy. We observed that TGF-β1 induced collagen production via NOX4 activation and ROS generation in LmcMF cells. Nox4 siRNA and inhibitors of TGF-β1 receptor and NOX significantly reduced TGF-β1-induced ROS and collagen production. Thus, in the present study, we revealed that collagen production in ISEMFs is induced via an NOX4-dependent pathway. This work supports a function for NOX4 in intestinal fibrogenesis and identifies it as a potential therapeutic target in recalcitrant fibrotic disorders of CD patients.

Impact of the Charlson comorbidity index and prognostic nutritional index on prognosis in patients with early gastric cancer after endoscopic submucosal dissection

BACKGROUND AND AIM

With the aging of society, comorbidities or nutritional status are assessed prior to endoscopic submucosal dissection (ESD) for early gastric cancer (EGC). However, it is uncertain which factors are important for predicting prognosis in EGC patients after ESD. Thus, we aimed to evaluate clinical outcomes of ESD for EGC, with respect to comorbidities or nutritional status.

METHODS

We carried out a retrospective study involving 708 EGC in 585 patients who were enrolled between April 2007 and March 2012. They were classified into two groups; an elderly (≥80 years) and non-elderly (<80 years) group. Short- and long-term outcomes were evaluated between the groups.

RESULTS

There were no significant differences regarding short-term outcomes. Overall survival (OS) rates in the elderly group were significantly lower than those in the non-elderly group (P = 0.001). OS rates in patients with a low (≤2) Charlson comorbidity index (CCI) were significantly higher than those in patients with a high (≥3) CCI, regardless of age. OS rates in patients with a high (≥47.7) prognostic nutritional index (PNI) were significantly higher than those in patients with a low (<47.7) PNI, regardless of age. In multivariate analysis, an Eastern Cooperative Oncology Group performance status (PS) ≥2 (hazard ratio [HR], 95% confidence interval: 3.23, 1.54-6.75), CCI ≥3 (HR 7.88, 4.50-13.80) and PNI <47.7 (HR 3.44, 2.00-5.90) were significantly associated with OS rate (P < 0.01).

CONCLUSION

CCI and PNI can be prognostic indicators for non-elderly and elderly patients with EGC after ESD.

Stenotic Ischemic Enteritis with Concomitant Hepatic Portal Venous Gas and Pneumatosis Cystoides Intestinalis

A 69-year-old man was admitted to a hospital with complaints of abdominal pain. Computed tomography showed hepatic portal venous gas and pneumatosis cystoides intestinalis. Conservative treatment was effective; however, after discharge, he developed complaints of vomiting. Fluoroscopic enteroclysis revealed a stricture in the jejunum necessitating admission to our hospital. Transoral balloon-assisted enteroscopy showed a circumferential ulcer with a stricture. The stricture was surgically resected, and a histopathological examination was consistent with ischemic enteritis. Stenotic ischemic enteritis should be considered among the differential diagnoses in a patient presenting with hepatic portal venous gas and pneumatosis cystoides intestinalis showing small intestinal obstruction.

Heme oxygenase-1 prevents murine intestinal inflammation

Heme oxygenases (HOs) are rate-limiting enzymes catabolizing heme to biliverdin, ferrous iron, and carbon monoxide, and of the three HO isoforms identified, HO-1 plays a protective role against inflammatory processes. In this study, we investigated the possible role of HO-1 in intestinal inflammation. Acute colitis was induced in male C57BL/6 (wild-type) and homozygous BTB and CNC homolog 1 (Bach1)-deficient mice, which show high HO-1 expression in the colonic mucosa, using dextran sodium sulfate. The disease activity index, myeloperoxidase activity, and inflammatory cytokines in the colonic mucosa were evaluated 7 days after dextran sodium sulfate-dependent colitis induction. We also evaluated the impact of HO-1 inhibition using zinc protoporphyrin IX (25 mg/kg i.p., daily). After dextran sodium sulfate administration, HO-1 mRNA and protein expression increased in a time-dependent manner. Disease activity index score, myeloperoxidase activity, and colonic production of TNF-α and IFN-γ were increased after dextran sodium sulfate administration, and co-administration of zinc protoporphyrin IX enhanced their increase. In addition, disease activity index in Bach1-deficient was significantly lower after dextran sodium sulfate administration than that in wild type mice. These results indicate that HO-1 plays a protective role against dextran sodium sulfate-induced intestinal inflammation, possibly by regulating pro-inflammatory cytokines in intestinal tissues.

Abstract 5540: Clinical significance of soluble forms of immune checkpoint molecules in advanced esophageal cancer

Background: Immune checkpoint molecules such as PDL1 and CD155 are expressed on cancer cells and regulate tumor immunity by binding to ligands on immune cells. Although soluble forms of immune checkpoint molecules have been detected in the blood, the roles of these soluble forms have not been fully elucidated. In this study, the clinical significance of soluble forms of immune checkpoint molecules in advanced esophageal cancer was examined. Methods: Soluble PDL1 (sPDL1), PD1(sPD1), CD155(sCD155), and LAG3 (sLAG3) were measured by ELISA in 47 patients who were diagnosed with advanced esophageal cancer and planned to receive multidisciplinary treatment in our department from April 2015 to March 2017. The levels of these molecules in cancer patients were compared with those of 24 control subjects. Results: The mean age of the tumor group was 66 years (41 years to 78 years), the ratio of males and females was 42: 5. Based on TNM-UICC stage grouping, 8, 24 and 15 patients were in clinical stage II, III and IV, respectively. All patients underwent chemotherapy, 25 patients underwent radiation therapy in combination with chemotherapy, and 26 underwent surgical therapy after chemotherapy. There was no difference in age between two groups, but the proportion of male was significantly higher in the cancer group than in the tumor group (P = 0.014). Regarding sPDL1 and sLAG3, there was no significant difference between two groups, but the levels of sPD1 and sCD155 were significantly higher in the tumor group than the control group (sPD1: P = 0.0225; sCD155: P = 0.0006). In subgroup analysis of patients with esophageal cancer, there was a tendency for higher levels of sPD1 in patients with lymph node metastasis (P = 0.150), large tumor diameter (P = 0.189), and higher levels of serum SCC (P = 0.078). The level of sPD1 was related to neither response rate nor overall survival. On the other hand, we did not find any association between clinical characteristics and the level of sCD155. However, the level of sCD155 tended to be higher in patients with response to chemotherapy (CR / PR) (P = 0.111) and in patients with a longer survival (P = 0.183). Discussion: We confirmed that sPD1 and sCD155 are elevated in advanced esophageal cancer. In addition, results in this study suggested that sCD155 may be a biomarker for therapeutic effect or prognostic prediction of esophageal cancer. Large-scale studies are needed to confirm our findings.

Citation Format: Juichiro Yoshida, Takeshi Ishikawa, Takayuki Ohta, Tomoyo Yasuda, Osamu Dohi, Tetsuya Okayama, Naohisa Yoshida, Kazuhiro Kamada, Kazuhiko Uchiyama, Osamu Handa, Tomohisa Takagi, Hideyuki Konishi, Yuji Naitoh, Yoshito Itoh. Clinical significance of soluble forms of immune checkpoint molecules in advanced esophageal cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 5540.

Phase I clinical trial of adoptive transfer of expanded natural killer cells in combination with IgG1 antibody in patients with gastric or colorectal cancer

Natural killer (NK) cells exhibit strong cytotoxic activity against tumor cells without prior sensitization, and have the potential to exert antibody-dependent cellular cytotoxicity (ADCC). In this clinical trial, we examined the safety and efficacy of the use of NK cells, generated using a novel expansion system, in combination with IgG1 antibodies for the treatment of advanced gastric or colorectal cancers. Treatment consisted of trastuzumab- or cetuximab-based chemotherapy, plus adoptive NK cell therapy. For administration of expanded NK cells, dose escalation with a sequential 3 + 3 design was performed in three steps, at doses of 0.5 × 109 , 1.0 × 109 , and 2.0 × 109 cells/injection (N = 9). After 3 days of IgG1 antibody administration, patients were infused with expanded NK cells three times at triweekly intervals. NK cell populations expanded with our system were confirmed as being enriched in NK cells (median 92.9%) with high expression of NKG2D (97.6%) and CD16 (69.6%). The combination therapy was very well tolerated with no severe adverse events. Among six evaluable patients, four presented stable disease (SD) and two presented progressive disease. Of the four SD patients, three showed an overall decrease in tumor size after combination therapy. Immune monitoring suggested that combination therapy enhanced whole blood IFN-γ production and reduced peripheral regulatory T cells (Tregs). In conclusion, this phase I trial provides evidence of good tolerability, induction of Th1 immune responses, and preliminary anti-tumor activity for this combination therapy, in patients with advanced gastric and colorectal cancer that have received previous therapy.

Phase I clinical trial of adoptive transfer of expanded natural killer cells in combination with IgG1 antibody in patients with gastric or colorectal cancer

Natural killer (NK) cells exhibit strong cytotoxic activity against tumor cells without prior sensitization, and have the potential to exert antibody-dependent cellular cytotoxicity (ADCC). In this clinical trial, we examined the safety and efficacy of the use of NK cells, generated using a novel expansion system, in combination with IgG1 antibodies for the treatment of advanced gastric or colorectal cancers. Treatment consisted of trastuzumab- or cetuximab-based chemotherapy, plus adoptive NK cell therapy. For administration of expanded NK cells, dose escalation with a sequential 3 + 3 design was performed in three steps, at doses of 0.5 × 109 , 1.0 × 109 , and 2.0 × 109 cells/injection (N = 9). After 3 days of IgG1 antibody administration, patients were infused with expanded NK cells three times at triweekly intervals. NK cell populations expanded with our system were confirmed as being enriched in NK cells (median 92.9%) with high expression of NKG2D (97.6%) and CD16 (69.6%). The combination therapy was very well tolerated with no severe adverse events. Among six evaluable patients, four presented stable disease (SD) and two presented progressive disease. Of the four SD patients, three showed an overall decrease in tumor size after combination therapy. Immune monitoring suggested that combination therapy enhanced whole blood IFN-γ production and reduced peripheral regulatory T cells (Tregs). In conclusion, this phase I trial provides evidence of good tolerability, induction of Th1 immune responses, and preliminary anti-tumor activity for this combination therapy, in patients with advanced gastric and colorectal cancer that have received previous therapy.

Phase I clinical trial of adoptive transfer of expanded natural killer cells in combination with IgG1 antibody in patients with gastric or colorectal cancer

Natural killer (NK) cells exhibit strong cytotoxic activity against tumor cells without prior sensitization, and have the potential to exert antibody-dependent cellular cytotoxicity (ADCC). In this clinical trial, we examined the safety and efficacy of the use of NK cells, generated using a novel expansion system, in combination with IgG1 antibodies for the treatment of advanced gastric or colorectal cancers. Treatment consisted of trastuzumab- or cetuximab-based chemotherapy, plus adoptive NK cell therapy. For administration of expanded NK cells, dose escalation with a sequential 3 + 3 design was performed in three steps, at doses of 0.5 × 109 , 1.0 × 109 , and 2.0 × 109 cells/injection (N = 9). After 3 days of IgG1 antibody administration, patients were infused with expanded NK cells three times at triweekly intervals. NK cell populations expanded with our system were confirmed as being enriched in NK cells (median 92.9%) with high expression of NKG2D (97.6%) and CD16 (69.6%). The combination therapy was very well tolerated with no severe adverse events. Among six evaluable patients, four presented stable disease (SD) and two presented progressive disease. Of the four SD patients, three showed an overall decrease in tumor size after combination therapy. Immune monitoring suggested that combination therapy enhanced whole blood IFN-γ production and reduced peripheral regulatory T cells (Tregs). In conclusion, this phase I trial provides evidence of good tolerability, induction of Th1 immune responses, and preliminary anti-tumor activity for this combination therapy, in patients with advanced gastric and colorectal cancer that have received previous therapy.

Phase I clinical trial of adoptive transfer of expanded natural killer cells in combination with IgG1 antibody in patients with gastric or colorectal cancer

Natural killer (NK) cells exhibit strong cytotoxic activity against tumor cells without prior sensitization, and have the potential to exert antibody-dependent cellular cytotoxicity (ADCC). In this clinical trial, we examined the safety and efficacy of the use of NK cells, generated using a novel expansion system, in combination with IgG1 antibodies for the treatment of advanced gastric or colorectal cancers. Treatment consisted of trastuzumab- or cetuximab-based chemotherapy, plus adoptive NK cell therapy. For administration of expanded NK cells, dose escalation with a sequential 3 + 3 design was performed in three steps, at doses of 0.5 × 109 , 1.0 × 109 , and 2.0 × 109 cells/injection (N = 9). After 3 days of IgG1 antibody administration, patients were infused with expanded NK cells three times at triweekly intervals. NK cell populations expanded with our system were confirmed as being enriched in NK cells (median 92.9%) with high expression of NKG2D (97.6%) and CD16 (69.6%). The combination therapy was very well tolerated with no severe adverse events. Among six evaluable patients, four presented stable disease (SD) and two presented progressive disease. Of the four SD patients, three showed an overall decrease in tumor size after combination therapy. Immune monitoring suggested that combination therapy enhanced whole blood IFN-γ production and reduced peripheral regulatory T cells (Tregs). In conclusion, this phase I trial provides evidence of good tolerability, induction of Th1 immune responses, and preliminary anti-tumor activity for this combination therapy, in patients with advanced gastric and colorectal cancer that have received previous therapy.

Phase I clinical trial of adoptive transfer of expanded natural killer cells in combination with IgG1 antibody in patients with gastric or colorectal cancer

Natural killer (NK) cells exhibit strong cytotoxic activity against tumor cells without prior sensitization, and have the potential to exert antibody-dependent cellular cytotoxicity (ADCC). In this clinical trial, we examined the safety and efficacy of the use of NK cells, generated using a novel expansion system, in combination with IgG1 antibodies for the treatment of advanced gastric or colorectal cancers. Treatment consisted of trastuzumab- or cetuximab-based chemotherapy, plus adoptive NK cell therapy. For administration of expanded NK cells, dose escalation with a sequential 3 + 3 design was performed in three steps, at doses of 0.5 × 109 , 1.0 × 109 , and 2.0 × 109 cells/injection (N = 9). After 3 days of IgG1 antibody administration, patients were infused with expanded NK cells three times at triweekly intervals. NK cell populations expanded with our system were confirmed as being enriched in NK cells (median 92.9%) with high expression of NKG2D (97.6%) and CD16 (69.6%). The combination therapy was very well tolerated with no severe adverse events. Among six evaluable patients, four presented stable disease (SD) and two presented progressive disease. Of the four SD patients, three showed an overall decrease in tumor size after combination therapy. Immune monitoring suggested that combination therapy enhanced whole blood IFN-γ production and reduced peripheral regulatory T cells (Tregs). In conclusion, this phase I trial provides evidence of good tolerability, induction of Th1 immune responses, and preliminary anti-tumor activity for this combination therapy, in patients with advanced gastric and colorectal cancer that have received previous therapy.