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Background: Although Helicobacter-induced gastric inflammation is the major predisposing factor for gastric carcinogenesis, the precise mechanism by which chronic gastritis causes gastric cancer remains unclear. Intestinal and spasmolytic polypeptide-expressing metaplasia (SPEM) is considered as precancerous lesions, changes in epithelial tissue stem/progenitor cells after chronic inflammation has not been clarified yet. In this study, we utilized three-dimensional gastric epithelial cell culture systems that could form organoids, mimicking gastric epithelial layer, and characterized the changes in epithelial cells after chronic Helicobacter felis infection.Methods: We used three mice model; 1) long-term H. felis infection, 2) H. felis eradication, and 3) MNU chemical carcinogenesis model. We performed cRNA microarray analysis after organoid culture, and analyzed the effects of chronic gastric inflammation on tissue stem cells, by the size of organoid, mRNA expression profile and immunohistochemical analysis.Results: The number of organoids cultured from gastric epithelial cells was significantly higher in organoids isolated from H. felis-infected mice compared with those from uninfected gastric mucosa. Based on the mRNA expression profile, we found that possible stem cell markers such as Cd44, Dclk1, and genes associated with the intestinal phenotype, such as Villin, were increased in organoids isolated from H. felis-infected mucosa compared with the control. The upregulation of these genes were cancelled after H. felis eradication. In a xenograft model, tumors were generated only from organoids cultured from carcinogen-treated gastric mucosa, not from H. felis infected mucosa or control organoids.Conclusions: Our results suggested that, as a possible mechanism of gastric carcinogenesis, chronic inflammation induced by H. felis infection increased the number of tissue stem/progenitor cells and the expression of stem cell markers. These findings suggest that chronic inflammation may alter the direction of differentiation toward undifferentiated state and that drawbacks may enable cells to redifferentiate to intestinal metaplasia or neoplasia. [ABSTRACT FROM AUTHOR]

Background: Although some molecularly targeted drugs for colorectal cancer are used clinically and contribute to a better prognosis, the current median survival of advanced colorectal cancer patients is not sufficient. Autophagy, a basic cell survival mechanism mediated by recycling of cellular amino acids, plays an important role in cancer. Recently, autophagy has been highlighted as a promising new molecular target. The unfolded protein response (UPR) reportedly act in complementary fashion with autophagy in intestinal homeostasis. However, the roles of UPR in colon cancer under autophagic inhibition remain to be elucidated. We aim to clarify the inhibitory effect of autophagy on colon cancer.Methods: We crossed K19 (CreERT) and Atg5 (flox/flox) mice to generate Atg5 (flox/flox)/K19 (CreERT) mice. Atg5 (flox/flox)/K19 (CreERT) mice were first treated with azoxymethane/dextran sodium sulfate and then injected with tamoxifen to inhibit autophagy in CK19-positive epithelial cells. To examine the anti-cancer mechanisms of autophagic inhibition, we used colon cancer cell lines harboring different p53 gene statuses, as well as small interfering RNAs (siRNAs) targeting Atg5 and immunoglobulin heavy-chain binding protein (BiP), a chaperone to aid folding of unfolded proteins.Results: Colon tumors in Atg5 (flox/flox)/K19 (CreERT) mice showed loss of autophagic activity and decreased tumor size (the total tumor diameter was 28.1 mm in the control and 20.7 mm in Atg5 (flox/flox)/K19 (CreERT) mice, p = 0.036). We found that p53 and UPR/endoplasmic reticulum (ER) stress-related proteins, such as cleaved caspase 3, and CAAT/enhancer-binding protein homologous protein, are up-regulated in colon tumors of Atg5 (flox/flox)/K19 (CreERT) mice. Although Atg5 and BiP silencing, respectively, increased apoptosis in p53 wild type cells, Atg5 silencing alone did not show the same effect on apoptosis in p53 mutant cells. However, co-transfection of Atg5 and BiP siRNAs led to increased apoptosis in p53 mutant cells.Conclusions: Blocking autophagy has potential in the treatment of colon cancer by inducing apoptosis via p53 and ER stress, and suppressing the UPR pathway is a valid strategy to overcome resistance to autophagic inhibition. [ABSTRACT FROM AUTHOR]

Background: Endoscopic biliary stenting (EBS) is one of the most important palliative treatments for biliary tract cancer. However, reflux cholangitis arising from bacterial adherence to the inner wall of the stent must be avoided. We evaluated the use of EBS above the sphincter of Oddi to determine whether reflux cholangitis could be prevented in preoperative cases. Methods: Fifty-seven patients with primary biliary tract cancer were retrospectively recruited for the evaluation of stent placement either above (n = 25; inside stent group) or across (n = 32; conventional stent group) the sphincter of Oddi. We compared the stent patency periods prior to the time of surgical resection. Results: The preoperative periods were 96.3 days in the conventional stent group and 96.8 days in the inside stent group (P = 0.979). Obstructive jaundice and/or acute cholangitis occurred in 7 patients (28.0%) in the inside stent group and in 15 patients (46.9%) in the conventional stent group during the preoperative period (P = 0.150). The average patency periods of the stents were 85.2 days (range, 13-387 days) for the inside stent group and 49.1 days (range, 9-136 days) for the conventional stent group (log-rank test: P = 0.009). The mean numbers of re-interventions because of stent occlusion were 0.32 for the inside stent group and 1.03 for the conventional stent group (P = 0.026). Post-endoscopic retrograde cholangiopancreatography complications occurred in 2 patients in the inside stent group and 4 patients in the conventional stent group (P = 0.516). Postoperative liver abscess occurred in 1 patient in the inside stent group and 5 patients in the conventional stent group (P = 0.968). Inside stent placement was the only significant preventative factor associated with stent obstruction based on univariate (hazard ratio [HR], 0.286; 95% confidence interval [CI], 0.114-0.719; P = 0.008) and multivariate (HR, 0.292; 95% CI, 0.114-0.750; P = 0.011) analyses. Conclusion: Temporary plastic stent placement above the sphincter of Oddi is a better bridging treatment than conventional stent placement in preoperative primary biliary tract cancer. [ABSTRACT FROM AUTHOR]

Background: Non-adherence to aminosalicylates is observed among 30% to 45% of patients with ulcerative colitis and increases the risk of relapse. The Health Belief Model is a theoretical model that could offer a broader perspective to improve patients' self-medication adherence. This study aimed to develop a screening instrument based on the Health Belief Model to screen patients with ulcerative colitis who had a high possibility of current non-adherence to aminosalicylates. The study was also designed to allow examination of factors of nonadherence. Methods: A multicenter, cross-sectional study was conducted in outpatients diagnosed with ulcerative colitis and prescribed aminosalicylates. Non-adherence was defined as taking less than 80% of the prescribed dose. We hypothesized that there was a significant relationship between current aminosalicylate non-adherence and five components of the HBM: beliefs about taking aminosalicylates, disease characteristics, medication characteristics, abdominal symptoms, and sociodemographic characteristics. A logistic regression model was applied and the coefficients converted to a numeric scores in order to develop a screening instrument which could reliably discriminate non-adherent and adherent subjects. Results: Non-adherence was observed in 127 (29.6%) of the 429 enrolled subjects. Lower perceptions of belief in taking aminosalicylates, absence of visible bleeding, eight daily tablets or less taken, and no concomitant use of thiopurines were related to non-adherence. We then developed a screening instrument comprising 22 items. When the cut-off point was set at 60, the instrument showed 85.0% sensitivity and 69.2% specificity with an area under the curve of 0.84 (95% confidence interval = 0.79-0.91). Conclusions: The instrument appeared to be reliable for identifying patients with a high possibility of current non-adherence to aminosalicylates. Further, the instrument may provide useful information for detecting patients with a high possibility of current non-adherence and for assessing factors of non-adherence. On the other hand, we need to evaluate disease activity more strictly and examine whether it is included in the screening instrument in the future. [ABSTRACT FROM AUTHOR]

Background Crohn's disease (CD) is routinely evaluated using clinical symptoms, laboratory variables, and the CD activity index (CDAI). However, clinical parameters are often nonspecific and do not precisely reflect the actual activity of CD small-intestinal lesions. The purposes of this prospective study were to compare color Doppler ultrasound (US) findings with histological findings from surgically resected specimens and confirm the hypothesis that color Doppler US can distinguish tissue inflammation and fibrosis. Methods Among 1764 consecutive patients who underwent color Doppler US examinations, 10 patients with CD (12 small-intestinal CD lesions) who underwent US examinations before elective small-intestine resection were evaluated in the present study. Areas of thickened intestinal walls were evaluated in terms of blood flow using color Doppler US imaging. The blood flow was semiquantitatively classified as "hyper-flow" and "hypo-flow" according to the Limberg score. Resected lesions were macroscopically and histopathologically processed. Inflammatory cell infiltration, fibrosis and vascularity were evaluated by myeloperoxidase (granulocytes), CD163 (macrophages), CD79a (B cells), CD3 (T cells), Masson's trichrome (fibrosis), and factor VIII staining (vascular walls). All histopathological images were entered into virtual slide equipment and quantified using a quantitative microscopy integrated system (TissueMorph™). Results There were no significant differences in disease features or laboratory findings between "hypo-flow" lesions (n = 4) and "hyper-flow" lesions (n = 8). Histopathologically, "hyperflow" lesions showed significantly greater bowel wall vascularity (factor VIII) (p = 0.047) and inflammatory cell infiltration, including CD163 macrophages (p = 0.008), CD3 T cells, and CD79a B cells (p = 0.043), than did "hypo-flow" lesions. There was no apparent association between the blood flow and CDAI. Conclusions In this study, active CD lesions were macroscopically visible in surgical specimens of patients with increased blood flow on preoperative color Doppler US imaging. Additionally, these CD lesions exhibited significantly greater vascularity and numbers of inflammatory leukocytes microscopically. Color Doppler US may predict tissue inflammation and fibrosis in small-intenstinal CD lesions. [ABSTRACT FROM AUTHOR]