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Background/Aim: Lymphoid follicles hyperplasia (LH) is sometimes observed in the normal colon as small, round, yellowish-white nodules. LH is associated with food hypersensitivity and bowel symptoms and histologically characterized as intense infiltration of lymphocytes or plasmacytes. It is suggested that LH represents inflammatory immune response in the colonic mucosa. We investigated the presence of LH in the normal colonic mucosa and its association with incidence of colorectal lesions including colorectal cancer, adenoma and hyperplastic polyp. Patients/Methods: 605 participants undergoing colonoscopy for various indications were enrolled. Presence of LH in the proximal colon (appendix, cecum and the ascending colon) was observed using the blue laser imaging (BLI) endoscopy, a new generation image enhanced endoscopy (IEE) system. LH was defined as well demarcated white nodules. Elevated LH with erythema was distinguished as LH severe. Association between presence of LH and occurrence of colorectal lesions was investigated. Results: Prevalence of all colorectal lesions and adenoma were significantly lower in LH severe group compared to the LH negative group (P = 0.0008, 0.0009, respectively). Mean number of all colorectal lesions and adenoma were also lower in LH severe group compared to the LH negative group (P = 0.005, 0.003 respectively). The logistic regression with adjustment for gender and age demonstrated that presence of LH severe held significantly lower risk of all colorectal lesions (OR = 0.48, 95%CI = 0.27–0.86) and adenoma (OR = 0.47, 95%CI = 0.26–0.86). Conclusion: LH in the colonic mucosa visualized by IEE is useful endoscopic finding to predict risk of colorectal adenoma. [ABSTRACT FROM AUTHOR]

Background/Aim: In the colorectum, lymphoid follicles hyperplasia (LH) is sometimes observed as small, round, yellowish-white nodules. The novel image-enhanced endoscopy system named blue laser imaging (BLI) provides enhanced the contrast of surface vessels using lasers for light illumination. We investigated the endoscopic features of LH observed by using BLI endoscopy and its association with chronic bowel symptoms. Patients/Methods: 300 participants undergoing colonoscopy for various indications were enrolled. Entire colorectum was observed by using BLI-bright mode with non-magnification view. LH was defined as well demarcated white nodules. Elevated LH with erythema was distinguished as LH severe. Results: LHs were observed more clearly by using BLI-bright mode compared to conventional white light colonoscopy and were also histologically confirmed as intense infiltration of lymphocytes or plasmacytes. LH was observed in 134 subjects (44.6%) and 67 (22.3%) were LH severe. LH was associated younger age (Odds ratio (OR) = 1.05, 95%Confidence Interval (95%CI) = 1.03–1.07, P<0.0001) and chronic bowel symptoms including constipation, hard stools, diarrhea and loose stools (all LH: OR = 4.03, 95%CI = 2.36–6.89, P<0.0001, LH severe: OR = 5.31, 95%CI = 2.64–10.71, P<0.0001). LH severe was closely associated with both constipation associated symptoms (OR = 3.94, 95%CI = 1.79–8.66, P = 0.0007) and diarrhea associated symptoms (OR = 5.22, 95%CI = 2.09–13.05, P = 0.0004). In particular, LH severe in the ascending colon was strongly associated with bowel symptoms (P<0.0001). Conclusion: LH, visualized by using BLI endoscopy was associated with bowel symptom, raising the possibility of pathogenic role of this endoscopic finding in the functional lower gastrointestinal disorders. [ABSTRACT FROM AUTHOR]

Background: Chemotherapy may improve outcomes in gastric cancer (GC), especially for the patients with advanced stage. To explore useful predictive factor for GC performing chemotherapy, we compared the tumor responses assessed using computed tomography (CT) with endoscopy based criteria. Methods: 192 GC patients performing chemotherapy were retrospectively studied. CT based response assessment was performed after 2 courses of treatment. Endoscopic evaluation according to The Japanese classification of gastric carcinoma was also performed at same period. Data were correlated with overall survival (OS) and progression-free survival (PFS). Results: Majority of the cases (n = 178, 93%) received S-1 based chemotherapy as the first line treatment. 55 (29%) and 91 (47%) cases were considered to be CT and endoscopic responders. Endoscopic responder was more clearly associated with better OS and PFS compared to CT based responder by the log-rank test (P<0.0001 vs. 0.01 and P<0.0001 vs. 0.008, respectively). The association was more striking among patients performing neoadjuvant chemotherapy (P<0.0001 vs. 0.15 and P<0.0001 vs. 0.1, respectively). Multivariate survival analysis using Cox's regression model revealed that endoscopic non-responder was the independent predictive factor, being more strongly associated with worse OS when compared to CT non-responder (hazard ratio: 4.60 vs. 1.77, 95% confidence interval: 2.83–7.49 vs.1.08–2.89, P<0.0001 vs. 0.02). More advanced T, N stage and cases who had peritoneal dissemination were significantly associated with endoscopic non-responder (all P values <0.01). Conclusion: Endoscopy based evaluation of primary lesions are clearly associated with prognosis in patients with GC who perform chemotherapy. [ABSTRACT FROM AUTHOR]

Background: The effect of H. pylori eradication in gastric cancer prevention can be attributed to the improvement of atrophic gastritis, which is a known risk of gastric cancer. However, gastric cancer has also been diagnosed after long-term H. pylori eradication. This study aimed to clarify the association between gastric atrophy and gastric cancer after H. pylori eradication, including its clinicopathological features. Methods: A total of 55 consecutive patients with 64 early gastric cancers (EGCs) diagnosed after H. pylori eradication were enrolled. The degree of endoscopic atrophy and the histological degrees of mononuclear cell infiltration, atrophy, and metaplasia in the corpus and adjacent mucosa of the EGCs were determined and scored. Results: The majority of EGCs (63/64) were located within the endoscopically assessed atrophic mucosa or along the atrophic border. The adjacent mucosa of the EGCs presented significantly higher degrees of all histological parameters than in the corpus (mononuclear cell infiltration, 0.86+/-0.09 vs. 0.51+/-0.11, P = 0.016; atrophy, 1.77+/-0.13 vs. 0.65+/-0.14, P<0.0001; metaplasia, 1.68+/-0.13 vs. 0.48+/-0.1, P<0.0001). The degree of endoscopic atrophy improved in the patients with longer post-H. pylori eradication periods; however, this trend was not observed for the histological parameters, and high degrees of atrophy and metaplasia were observed in the adjacent mucosa of the EGCs compared with the corpus during all periods (all P<0.05). The histological degrees of atrophy and metaplasia in the adjacent mucosa were particularly higher in the patients who underwent eradication due to gastric ulcers. Conclusions: Severe gastric atrophy remained in the adjacent mucosa of the EGCs after H. pylori eradication, which may be linked to gastric carcinogenesis. [ABSTRACT FROM AUTHOR]

Background: Epithelial-to-mesenchymal transition (EMT) is a phenomenon that allows the conversion of adherent epithelial cells to a mesenchymal cell phenotype, which enhances migratory capacity and invasiveness. Recent studies have suggested that EMT contributes to the pathogenesis of ulcerative colitis (UC). We investigated the promoter DNA methylation status of EMT-related genes in the colonic mucosa in UC. Methods: Colonic biopsies were obtained from the rectal inflammatory mucosa of 86 UC patients and the non-inflammatory proximal colonic mucosa of 10 paired patients. Bisulfite pyrosequencing was used to quantify the methylation of 5 candidate CpG island promoters (NEUROG1, CDX1, miR-1247, CDH1, and CDH13) and LINE1. Results: Using an unsupervised hierarchical clustering analysis, inflamed rectal mucosa was well separated from mucosa that appeared normal. The CDH1 and CDH13 promoters were significantly associated with patient age (p = 0.04, 0.03, respectively). A similar trend was found between those genes and the duration of disease (CDH1: p = 0.07, CDH13: p = 0.0002, mean of both: p<0.00001). Several positive associations were found between hypermethylation and severe clinical phenotypes (CDX1 and miR-1247 and a refractory phenotype: p = 0.04 and 0.006, respectively. miR-1247 and CDH1 hyper methylation and a more severe Mayo endoscopic subscore: miR-1247: p = 0.0008, CDH1: p = 0.03, mean of both: p = 0.003). When the severe clinical phenotype was defined as having any of five phenotypes (hospitalized more than twice, highest Mayo endoscopic subscore, steroid dependence, refractory, or a history of surgery) miR-1247 hypermethylation was associated with the same phenotype (p = 0.008). Conclusions: Our data suggest that variability in the methylation status of EMT-related genes is associated with more severe clinical phenotypes in UC. [ABSTRACT FROM AUTHOR]

Background: The neurochemical serotonin (5-HT) is an important signaling molecule in the gastrointestinal motor and sensory functions. A key regulator of 5-HT levels is the transmembrane serotonin transporter (5-HTT; SLC6A4) that governs the reuptake of 5-HT. Recent studies have indicated 5-HTT expression may be regulated by epigenetic mechanisms. We investigated DNA methylation status of SLC6A4 gene in the gastric mucosa from functional dyspepsia (FD) because of their potential role in dyspeptic symptoms. Methods: Endoscopic gastric biopsies were obtained from 78 subjects with no upper abdominal symptoms and 79 patients with FD. Bisulfite Pyrosequencing was carried out to determine the methylation status of promoter CpG islands (PCGIs), promoter non-CpG islands (PNCGIs) and gene body non-CpG islands (NPNCGIs) in the SLC6A4 gene. Gene expression was examined by real-time PCR. Results: In overall, methylation level of PCGIs was significantly lower in FD compared to control subjects (p = 0.04). On the other hand, methylation level of NPNCGIs was significantly higher in FD compared to control subjects (p = 0.03). Lower methylation level in PNCGIs was highlighted in the patients with PDS (p = 0.01), while higher methylation level in NPNCGIs was more prominent in the patients with EPS (p = 0.017). Methylation levels of PCGIs and PNCGIs were inversely correlated, while methylation levels of NPNCGIs was positively correlated with SLC6A4 mRNA levels in FD patients. Conclusions: Our data suggest that change in DNA methylation pattern of SLC6A4 in the gastric mucosa may have a role for developing FD. A role of epigenetics for developing FD needs to be further evaluated. [ABSTRACT FROM AUTHOR]

Background: The neurochemical serotonin (5-HT) is an important signaling molecule in the gastrointestinal motor and sensory functions. A key regulator of 5-HT levels is the transmembrane serotonin transporter (5-HTT; SLC6A4) that governs the reuptake of 5-HT. Recent studies have indicated 5-HTT expression may be regulated by epigenetic mechanisms. We investigated DNA methylation status of SLC6A4 gene in the gastric mucosa from functional dyspepsia (FD) because of their potential role in dyspeptic symptoms., Methods: Endoscopic gastric biopsies were obtained from 78 subjects with no upper abdominal symptoms and 79 patients with FD. Bisulfite Pyrosequencing was carried out to determine the methylation status of promoter CpG islands (PCGIs), promoter non-CpG islands (PNCGIs) and gene body non-CpG islands (NPNCGIs) in the SLC6A4 gene. Gene expression was examined by real-time PCR., Results: In overall, methylation level of PCGIs was significantly lower in FD compared to control subjects (p = 0.04). On the other hand, methylation level of NPNCGIs was significantly higher in FD compared to control subjects (p = 0.03). Lower methylation level in PNCGIs was highlighted in the patients with PDS (p = 0.01), while higher methylation level in NPNCGIs was more prominent in the patients with EPS (p = 0.017). Methylation levels of PCGIs and PNCGIs were inversely correlated, while methylation levels of NPNCGIs was positively correlated with SLC6A4 mRNA levels in FD patients., Conclusions: Our data suggest that change in DNA methylation pattern of SLC6A4 in the gastric mucosa may have a role for developing FD. A role of epigenetics for developing FD needs to be further evaluated.