Takahito Katano

Establishment of a long-term three-dimensional primary culture of mouse glandular stomach epithelial cells within the stem cell niche

Compared to the small intestine and colon, little is known about stem cells in the stomach because of a lack of specific stem cell markers and an in vitro system that allows long-term culture. Here we describe a long-term three-dimensional (3D) primary gastric culture system within the stem cell niche. Glandular stomach cells from neonatal mice cultured in collagen gel yielded expanding sphere-like structures for 3months. The wall of the gastrospheres consisted of a highly polarized epithelial monolayer with an outer lining of myofibroblasts. The epithelial cells showed a tall columnar cell shape, basal round nuclei, and mucus-filled cytoplasm as well as expression of MUC5AC, indicating differentiation into gastric surface mucous cells. These cells demonstrated the features of fully differentiated gastric surface mucous cells such as microvilli, junctional complexes, and glycogen and secretory granules. Fewer than 1% of cultured epithelial cells differentiated into enteroendocrine cells. Active proliferation of the epithelial cells and many apoptotic cells in the inner lumen revealed the rapid cell turnover in gastrospheres in vitro. This method enables us to investigate the role of signaling between cell-cell and epithelial-mesenchymal interactions in an environment that is extremely similar to the in vivo environment.

The efficacy of transcatheter arterial embolization as the first‐choice treatment after failure of endoscopic hemostasis and endoscopic treatment resistance factors

Aim:  The aim of this retrospective study was to evaluate the efficacy of transcatheter arterial embolization (TAE) as the first‐choice treatment in patients with bleeding peptic ulcer after the failure of endoscopic hemostasis. An additional objective was to clarify endoscopic treatment resistance factors.

Colon Mucosa Exhibits Loss of Ectopic MUC5AC Expression in Patients with Ulcerative Colitis Treated with Oral Tacrolimus

Background. Tacrolimus (FK506) is effective for patients with ulcerative colitis (UC). However, there are few reports on tacrolimus therapy (TT) with respect to the relationship with endoscopic and clinicopathologic findings. Methods. Thirty patients with moderate/severe active UC refractory to or dependent on corticosteroid were treated with oral tacrolimus. The expression of ectopic MUC5AC in the colon was pathologically analyzed before and at 12 weeks after TT, evaluating the Mayo score and steroid-sparing effects. Results. Both mean disease and endoscopic activity index scores were reduced at levels of statistical significance in 26 UC patients receiving more than one month of TT (P < 0.0001). The dose of prednisolone was reduced by a statistically significant amount (P = 0.00022), and 14 of the 26 patients (53.8%) had steroid-free status 12 weeks after TT. The decrease in ectopic MUC5AC expression in the mucous cells of the colon was significantly associated with endoscopic improvement of inflammation in the UC patients with TT (P = 0.043). Loss of ectopic MUC5AC expression was detected in all patients who had complete response. Conclusions. Tacrolimus appears to be effective for the treatment of moderate/severe UC patients. Loss of ectopic MUC5AC expression may be important for pathologic remission in the colon of UC patients.

Therapeutic Effects of Biobran, Modified Arabinoxylan Rice Bran, in Improving Symptoms of Diarrhea Predominant or Mixed Type Irritable Bowel Syndrome: A Pilot, Randomized Controlled Study

Background. Recently, it was revealed that low grade mucosal inflammation and/or immune imbalance of the lower digestive tract is one of the mechanisms involved in symptom generation in patients with irritable bowel syndrome (IBS). Biobran, arabinoxylan compound derived from rice bran, has been reported to have several biological actions such as anti-inflammatory and immune modulatory effects. So we investigated the therapeutic effects of Biobran in patients with IBS. Method. Forty patients with diarrhea predominant or mixed type IBS were randomly assigned to either a Biobran group for treatment with Biobran or a placebo group. Therapeutic efficacy and IBS symptoms were assessed subjectively by the patients after 4 weeks of administration. Results. The global assessment was effective in 63.2% of the Biobran group and in 30% of the placebo group (P < 0.05, Biobran group versus placebo group). Biobran group showed a significant decrease in the score of diarrhea and constipation and in CRP value. However, no significant changes were observed in the placebo group. Conclusion. The administration of Biobran improved IBS symptoms. It is likely that anti-inflammatory and/or immune modulatory effects of Biobran might be useful in IBS patients.

Long-Term Efficacy of Adalimumab in Patients With Intestinal Behcet’s Disease: Eight Consecutive Cases

The long-term efficacy and safety of adalimumab (ADA) for the treatment of intestinal Behcet’s disease (BD) in the clinical setting have not been evaluated previously. This retrospective study evaluated the 52-week efficacy of ADA in BD patients. A total of eight patients who were refractory to conventional therapy were given ADA (160/80/40 mg every other week). Marked improvement (MI) was achieved by 10 weeks in five patients (62.5%), and by 52 weeks in six patients (75%). In addition, complete remission was obtained in two patients (25%) at both 10 and 52 weeks. Improvement of global gastrointestinal (GI) symptoms to score 0 was observed in three patients (37.5%) at 10 weeks and four patients (50%) at 52 weeks. Moreover, improvement of endoscopic assessment to score 0 was also seen in four patients (50%) at both 10 and 52 weeks. No adverse events were observed in any patients during the 52 weeks. In conclusion, ADA offers an effective, well-tolerated treatment for intestinal BD in patients who are refractory to conventional therapy.

Advances in refractory ulcerative colitis treatment: A new therapeutic target, Annexin A2

Medical treatment has progressed significantly over the past decade towards achieving and maintaining clinical remission in patients with refractory ulcerative colitis (UC). Proposed mediators of inflammation in UC include pro-inflammatory cytokines such as tumor necrosis factor-α (TNF-α) and interleukin-2, and the cell-surface adhesive molecule integrin α4β7. Conventional therapeutics for active UC include 5-aminosalicylic acid, corticosteroids and purine analogues (azathioprine and 6-mercaptopurine). Patients who fail to respond to conventional therapy are treated with agents such as the calicineurin inhibitors cyclosporine and tacrolimus, the TNF-α inhibitors infliximab or adalimumab, or a neutralizing antibody (vedolizumab) directed against integrin α4β7. These therapeutic agents are of benefit for patients with refractory UC, but are not universally effective. Our recent research on TNF-α shedding demonstrated that inhibition of annexin (ANX) A2 may be a new therapeutic strategy for the prevention of TNF-α shedding during inflammatory bowel disease (IBD) inflammation. In this review, we provide an overview of therapeutic treatments that are effective and currently available for UC patients, as well as some that are likely to be available in the near future. We also propose the potential of ANX A2 as a new molecular target for IBD treatment.

Combination Therapy With Adalimumab Plus Intensive Granulocyte and Monocyte Adsorptive Apheresis in Patients With Refractory Ulcerative Colitis

Background The efficacy and safety of combination therapy with adalimumab (ADA) plus intensive granulocyte and monocyte adsorptive apheresis (GMA) (two sessions per week) for the treatment of refractory ulcerative colitis (UC) have not been previously evaluated. Methods This retrospective study evaluated the 10-week efficacy of combination therapy with ADA plus intensive GMA on refractory UC patients, on clinical outcomes over 52 weeks under subsequent maintenance monotherapy of ADA, and the effect of combined azathioprine (AZA) with ADA at failure to achieve clinical remission at 10 weeks and at flare-up by 52 weeks. Ten patients were given initial combination therapy of ADA (160/80/40 mg every other week) plus intensive GMA. One patient received total colectomy because of poor response. Results Of nine patients who received this combination therapy, 55.6% displayed cumulative clinical remission at 10 weeks and 33.3% displayed such remission at 52 weeks under subsequent maintenance monotherapy of ADA. The percentage of patients with mucosal healing at 10 weeks (endoscopy subscore ≤ 1) was 66.7%. Adverse events were observed in three patients (pneumonia, cerebral infarction and headache). Conclusion It was concluded that combination therapy with ADA plus intensive GMA is useful for induction of clinical remission in refractory UC patients, and is well tolerated.

Managing refractory Crohn's disease: challenges and solutions.

The goals of treatment for active Crohn’s disease (CD) are to achieve clinical remission and improve quality of life. Conventional therapeutics for moderate-to-severe CD include 5-aminosalicylic acid, corticosteroids, purine analogs, azathioprine, and 6-mercaptopurine. Patients who fail to respond to conventional therapy are treated with tumor necrosis factor (TNF)-α inhibitors such as infliximab and adalimumab, but their efficacy is limited due to primary nonresponse or loss of response. It is suggested that this requires switch to another TNF-α inhibitor, a combination therapy with TNF-α blockade plus azathioprine, or granulocyte and monocyte adsorptive apheresis, and that other therapeutic options having different mechanisms of action, such as blockade of inflammatory cytokines or adhesion molecules, are needed. Natalizumab and vedolizumab are neutralizing antibodies directed against integrin α4 and α4β7, respectively. Ustekinumab is a neutralizing antibody directed against the receptors for interleukin-12 and interleukin-23. Here, we provide an overview of therapeutic treatments that are effective and currently available for CD patients, as well as some that likely will be available in the near future. We also discuss the advantages of managing patients with refractory CD using a combination of TNF-α inhibitors plus azathioprine or intensive monocyte adsorptive apheresis.

Ectopic Gastric and Intestinal Phenotypes, Neuroendocrine Cell Differentiation, and SOX2 Expression Correlated With Early Tumor Progression in Colorectal Laterally Spreading Tumors

Micro‐Abstract We analyzed 105 colorectal laterally spreading tumors (LSTs) resected by endoscopic submucosal dissection and investigated clinicopathologic differences among LST subtypes to identify factors indicative of malignant transformation and invasion. Ectopic gastric and intestinal phenotypes, neuroendocrine cell differentiation, and SOX2 expression differ according to tumor grade in colorectal LSTs, and these markers are correlated with early tumor progression in each LST subtype. Introduction: The significance of the ectopic gastric phenotype remains unclear in patients with colorectal laterally spreading tumors (LSTs). We investigated clinicopathologic differences among LST subtypes, aiming to identify factors indicative of malignant transformation and invasion that are linked to ectopic gastric phenotype and tumor progression. Materials and Methods: We analyzed the morphologic characteristics of 105 colorectal LSTs resected by endoscopic submucosal dissection. LSTs were classified into 2 subtypes: granular (G‐LST) and nongranular (NG‐LST). Resected LSTs were analyzed histologically and were immunohistochemically stained for MUC5AC, MUC6, chromogranin A, CD10, and SOX2. Results: The 105 LSTs included 60 G‐LSTs and 45 NG‐LSTs. By histology, G‐LSTs comprised 5 adenomas with low‐grade dysplasia (LAs), 45 adenomas with high‐grade dysplasia (HAs), and 10 adenocarcinomas invading the submucosa (SMs). NG‐LSTs comprised 8 LAs, 25 HAs, and 12 SMs. MUC5AC positivity was significantly higher in G‐LSTs compared to NG‐LSTs (P = .002), and MUC5AC positivity in HA lesions was significantly higher than in LA lesions (P = .01). MUC6 and SOX2 positivity in SM G‐LSTs, and chromogranin A positivity in SM NG‐LSTs were significantly higher than in HAs (P = .01, .01, and .03, respectively). CD10 positivity in SM NG‐LSTs was significantly higher than in HAs and LAs (P = .02 and .01, respectively). Conclusion: Ectopic gastric and intestinal phenotypes, neuroendocrine cell differentiation, and SOX2 expression differ according to tumor grade in colorectal LSTs, and these markers are correlated with early tumor progression in each LST subtype.

Adalimumab Treatment in Biologically Naïve Crohn's Disease: Relationship with Ectopic MUC5AC Expression and Endoscopic Improvement.

Background. Adalimumab (ADA) is effective for patients with Crohns disease (CD). However, there have been few reports on ADA therapy with respect to its relationship with pathologic findings and drug efficacy in biologically naïve CD cases. Methods. Fifteen patients with active biologically naïve CD were treated with ADA. We examined them clinically and pathologically with ectopic MUC5AC expression in the lesions before and after 12 and 52 weeks of ADA therapy, retrospectively. Results. Both mean CD activity index scores and serum C-reactive protein values were significantly lower after ADA therapy (P < 0.001). In the MUC5AC negative group, all cases exhibited clinical remission (CR) and endoscopic improvement at 52 weeks. In MUC5AC positive groups, loss of MUC5AC expression was detected in cases having CR and endoscopic improvement at 52 weeks, while remnant ectopic MUC5AC expression was observed in those exhibiting no endoscopic improvement and flare up after 52 weeks. Conclusions. ADA leads to CR and endoscopic improvement in biologically naïve CD cases. In addition, ectopic MUC5AC expression may be a predictive marker of flare up and endoscopic improvement in the intestines of CD patients.