Hisashi Shiga

Changes of faecal microbiota in patients with Crohn's disease treated with an elemental diet and total parenteral nutrition.

BACKGROUND Intestinal microbiota contributes to the pathogenesis of Crohns disease. Elemental diet and total parenteral nutrition are effective therapies for Crohns disease; however, changes of microbiota as a result of both treatments have not been fully elucidated. AIM To elucidate changes of faecal microbiota in Crohns disease patients treated with elemental diet and total parenteral nutrition. METHODS Stool samples were collected from 33 active Crohns disease patients and 17 healthy subjects, and recollected after elemental diet (8 patients) and total parenteral nutrition (9 patients). Terminal restriction fragment length polymorphism analysis of bacterial 16srDNA was performed to evaluate the whole microbiota. Specific quantitative PCR was then used to determine populations of predominant bacterial groups. RESULTS In Crohns disease patients, the number of terminal restriction fragments, which reflects bacterial species, was significantly lower. Populations of total bacteria and Bifidobacterium were significantly lower and the ratio of Enterococcus was higher. The number of terminal restriction fragments was significantly decreased after total parenteral nutrition, but not after elemental diet. Population of Bacteroides fragilis significantly decreased after elemental diet, while population of Enterococcus significantly increased after total parenteral nutrition. CONCLUSION Faecal microbiota in Crohns disease patients was markedly different from healthy subjects. Species diversity was reduced by total parenteral nutrition, but not by elemental diet.

Short and long-term outcomes of endoscopic balloon dilatation for Crohn’s disease strictures

AIM To investigate the short and long-term outcomes of endoscopic balloon dilatation (EBD) for Crohns disease (CD) strictures. METHODS Between January 1995 and December 2011, 47 EBD procedures were performed in 30 patients (8 females and 22 males) with CD. All patients had strictures through which an endoscope could not pass, and symptoms of these strictures included abdominal pain, abdominal fullness, nausea, and/or vomiting. The 47 strictures included 17 anastomotic and 30 de novo strictures. Endoscopy and dilatation were performed under conscious sedation with intravenous diazepam or flunitrazepam. The dilatations were all performed using through-the-scope balloons with diameters from 8 mm to 20 mm on inflation and lengths of 30-80 mm. Each dilatation session consisted of two to four, 3-min multistep inflations of the balloon, repeated at intervals of 1 wk until adequate dilatation (up to 15-20 mm in diameter) was achieved. The follow-up data were collected from medical records and analyzed retrospectively. Primary success was defined as passage of the scope through the stricture after EBD. Long-term outcomes were analyzed focusing on intervention-free survival and surgery-free survival demonstrated by the Kaplan-Meier method. (Intervention-free meant cases in which neither endoscopic balloon re-dilatation nor surgery was needed after the first dilatation during the observation period). The log rank test was used to evaluate the difference in long-term outcomes between anastomotic and de novo stricture cases. RESULTS Primary success was achieved in 44 of the 47 strictures (93.6%). Balloon dilatations failed in 3 cases (6.4%). In 1 case, EBD was a technical failure because the guide-wire could not be passed through the stricture which showed severe adhesion and was a flexural lesion of the intestine. In 2 cases, unexpected perforations occurred immediately after balloon dilatation. Of the 47 treatments, complications occurred in 5 (10.6%). All 5 patients had de novo strictures. One suffered bleeding, two high fever and there were colorectal perforations. One of the patients with a colorectal perforation was treated surgically, the other was managed conservatively. These 2 cases correspond to the two aforementioned EBD failures. Long-term outcomes were evaluated for the 44 successfully-treated strictures after a median follow-up of 26 mo (range, 2-172 mo). During the observation period, re-strictures after EBDs occurred in 26 cases (60.5%). Fourteen of these 26 re-stricture cases underwent EBD again, but in two EBD failed and surgery was ultimately performed in both cases. Twelve of the 26 re-stricture cases were initially treated surgically when the re-strictures occurred. Finally, 30 of the 47 strictures (63.8%) were successfully managed with EBD, allowing surgery to be avoided. Intervention-free survival evaluated by the Kaplan-Meier method was 75% at 12 mo, 58% at 24 mo, and 43% at 36 mo. There was no significant difference between the anastomotic strictures (n = 16) and de novo strictures (n = 28) in the intervention-free survival as evaluated by the log-rank test. Surgery-free survival evaluated by the Kaplan-Meier method was 90% at 12 mo, 75% at 24 mo, and 53% at 36 mo. The 16 anastomotic strictures were associated with significantly better surgery-free survivals than the 28 de novo strictures (log-rank test: P < 0.05). CONCLUSION Anastomotic strictures were associated with better long-term outcomes than de novo strictures, indicating that stricture type might be useful for predicting the long-term outcomes of EBD.

Erratum to: FCGR3A-158 polymorphism influences the biological response to infliximab in Crohn’s disease through affecting the ADCC activity

An association between FCGR3A-158 V/F polymorphism and biological responses to infliximab has been reported in Crohn’s disease (CD) in Western countries. However, little is known about the mechanism by which gene polymorphism affects the responses to infliximab. The aims of this study were to confirm the association in Japanese CD patients and to reveal the effect of gene polymorphism on biological responses to infliximab. Japanese CD patients were examined retrospectively at weeks 8 and 30. Clinical and biological responses were assessed by the Crohn’s disease activity index and C-reactive protein levels, respectively. The infliximab-binding affinity of natural killer (NK) cells from FCGR3A-158 V/V, V/F and F/F donors was examined. Infliximab-mediated antibody-dependent cell-mediated cytotoxicity (ADCC) activities were also determined using transmembrane TNF-α-expressing Jurkat T cells as target cells and peripheral blood mononuclear cells (PBMCs) from V/V, V/F and F/F donors as effector cells. Biological responses at week 8 were statistically higher in V/V patients, whereas no significant differences were observed in either clinical responses at weeks 8 and 30 or biological responses at week 30 among the three genotypes. NK cells and PBMCs from V/V patients also showed higher infliximab-binding affinity and infliximab-mediated ADCC activity, respectively. Our results suggest that FCGR3A-158 polymorphism is a predicting factor of biological responses to infliximab in the early phases. FCGR3A-158 polymorphism was also found to affect the infliximab-binding affinity of NK cells and infliximab-mediated ADCC activity in vitro, suggesting that an effect on ADCC activity influences biological responses to infliximab in CD patients.

Modulation of endoplasmic reticulum (ER) stress-induced autophagy by C/EBP homologous protein (CHOP) and inositol-requiring enzyme 1α (IRE1α) in human colon cancer cells.

To explore the relationship between UPR and autophagy in intestinal epithelial cells, we investigated whether autophagy was induced by endoplasmic reticulum (ER) stress in colon cancer cell lines. We demonstrated that autophagy was induced by ER stress in HT29, SW480, and Caco-2 cells. In these cells, inositol-requiring enzyme1α (IRE1α) and C/EBP homologous protein (CHOP) were involved in the ER stress-autophagy pathway, and CHOP was a regulator of IRE1α protein expression. Our findings suggest that CHOP promotes IRE1α and autophagy especially in ER stress conditions. This study will provide important insights into the disclosure of the ER stress-autophagy pathway.

Life-event stress induced by the Great East Japan Earthquake was associated with relapse in ulcerative colitis but not Crohn's disease: a retrospective cohort study

Objective Stress is thought to be one of the triggers of relapses in patients with inflammatory bowel disease (IBD). We examined the rate of relapse in IBD patients before and after the Great East Japan Earthquake. Design A retrospective cohort study. Settings 13 hospitals in Japan. Participants 546 ulcerative colitis (UC) and 357 Crohns disease (CD) patients who received outpatient and inpatient care at 13 hospitals located in the area that were seriously damaged by the earthquake. Data on patients clinical characteristics, disease activity and deleterious effects of the earthquake were obtained from questionnaires and hospital records. Primary outcome We evaluated the relapse rate (from inactive to active) across two consecutive months before and two consecutive months after the earthquake. In this study, we defined ‘active’ as conditions with a partial Mayo score=2 or more (UC) or a Harvey-Bradshaw index=6 or more (CD). Results Among the UC patients, disease was active in 167 patients and inactive in 379 patients before the earthquake. After the earthquake, the activity scores increased significantly (p<0.0001). A total of 86 patients relapsed (relapse rate=15.8%). The relapse rate was about twice that of the corresponding period in the previous year. Among the CD patients, 86 patients had active disease and 271 had inactive disease before the earthquake. After the earthquake, the activity indices changed little. A total of 25 patients experienced a relapse (relapse rate=7%). The relapse rate did not differ from that of the corresponding period in the previous year. Multivariate analyses revealed that UC, changes in dietary oral intake and anxiety about family finances were associated with the relapse. Conclusions Life-event stress induced by the Great East Japan Earthquake was associated with relapse in UC but not CD.

MicroRNA-320 family is downregulated in colorectal adenoma and affects tumor proliferation by targeting CDK6.

AIM To investigate the microRNA (miRNA) expression during histological progression from colorectal normal mucosa through adenoma to carcinoma within a lesion. METHODS Using microarray, the sequential changes in miRNA expression profiles were compared in colonic lesions from matched samples; histologically, non-neoplastic mucosa, adenoma, and submucosal invasive carcinoma were microdissected from a tissue sample. Cell proliferation assay was performed to observe the effect of miRNA, and its target genes were predicted using bioinformatics approaches and the expression profile of SW480 transfected with the miRNA mimics. mRNA and protein levels of the target gene in colon cancer cell lines with a mimic control or miRNA mimics were measured using qRT-PCR and Western blotting. The expression levels of miRNA and target gene in colorectal tissue samples were also measured. RESULTS Microarray analysis identified that the miR-320 family, including miR-320a, miR-320b, miR-320c, miR-320d and miR-320e, were differentially expressed in adenoma and submucosal invasive carcinoma. The miR-320 family, which inhibits cell proliferation, is frequently downregulated in colorectal adenoma and submucosal invasive carcinoma tissues. Seven genes including CDK6 were identified to be common in the results of gene expression array and bioinformatics analyses performed to find the target gene of the miR-320 family. We confirmed that mRNA and protein levels of CDK6 were significantly suppressed in colon cancer cell lines with miR-320 family mimics. CDK6 expression was found to increase from non-neoplastic mucosa through adenoma to submucosal invasive carcinoma tissues and showed an inverse correlation with miR-320 family expression. CONCLUSION MiR-320 family affects colorectal tumor proliferation by targeting CDK6, plays important role in its growth, and is considered to be a biomarker for its early detection.

What Determines the Later Clinical Course of Patients Who Do Not Undergo Colectomy at the First Attack A Japanese Cohort Study on Ulcerative Colitis

Background/Aims: Several earlier studies on factors predicting the long-term outcome of ulcerative colitis only encompassed treatment failure for one severe episode, or suffered from a lack of multivariate analyses. We aimed to identify factors assessable at diagnosis or after the first induction therapy which predicted relapse or later colectomy in patients with mild to severe ulcerative colitis. Methods: Clinical parameters (age, sex, disease extent, and disease activity at diagnosis) and laboratory data (hemoglobin, albumin, C-reactive protein, and erythrocyte sedimentation rate at diagnosis and 4 weeks after the first induction therapy) were evaluated in 296 patients (median follow-up 87 months). Factors predicting relapse and later colectomy were sought using the Cox proportional hazard model. Results: The presence of moderate or severe disease at diagnosis were significant predictors of relapse [adjusted hazard ratio (95% CI) 2.07 (1.48–2.89) and 1.70 (1.06–2.72), respectively] and later colectomy [3.40 (1.09–10.54) and 6.77 (1.92–23.86)]. After the first induction therapy, hemoglobin and albumin were associated with relapse [0.87 (0.76–0.99) and 0.58 (0.41–0.83)] and later colectomy [0.60 (0.47–0.77) and 0.11 (0.06–0.22)]. Conclusion: Relapse and later colectomy were associated with (1) disease activity at diagnosis and (2) lower levels of hemoglobin and albumin after the first induction therapy.

A Comparison of Short- and Long-Term Therapeutic Outcomes of Infliximab- versus Tacrolimus-Based Strategies for Steroid-Refractory Ulcerative Colitis

Background/Aims. Antitumor necrosis factor antibodies and calcineurin inhibitors have shown good therapeutic efficacy for steroid-refractory ulcerative colitis (UC). Although some studies have compared the efficacy of infliximab (IFX) and cyclosporin A, there are no published studies comparing IFX and tacrolimus (Tac). This study aimed to compare therapeutic efficacies between IFX- and Tac-based strategies for steroid-refractory UC. Methods. Between July 2009 and August 2013, 95 patients with steroid-refractory UC received either IFX (n = 48) or Tac (n = 47) in our hospital. In the IFX group, the patients continued to receive maintenance treatment with IFX. In the Tac group, patients discontinued Tac treatment up to 3 months and subsequently received thiopurine. We retrospectively compared the therapeutic outcomes between the groups. Results. There was no significant difference in the colectomy-free rate, clinical remission rate, and clinical response rate at 2 months between the groups. However, relapse-free survival was significantly higher in the IFX group than in the Tac group (p < 0.001; log-rank test). The proportions of serious adverse events did not differ between the groups. Conclusion. The findings of our study showed that IFX and Tac have similar short-term therapeutic efficacy for steroid-refractory UC. Maintenance treatment with IFX, however, yields better long-term outcomes than Tac-thiopurine bridging treatment.

De novo Crohn's disease following orthotopic liver transplantation: a case report and literature review.

The development of de novo Crohns disease (CD) after orthotopic liver transplantation (OLT) is rare, possibly due to the continuous use of immunosuppressive treatment. Although several cases of CD following OLT have been reported worldwide, there are currently so such cases in Japan. We herein report the case of a patient who newly developed CD after undergoing OLT for congenital biliary atresia. The patient subsequently underwent ileocecal resection and has since maintained clinical remission. This is the first report of this condition in Japan. We also review the literature concerning cases of de novo inflammatory bowel disease (IBD) developing after OLT, and discuss the causes of and role of immunosuppressive agents in treating IBD.

ATP-binding cassette subfamily B member 1 1236C/T polymorphism significantly affects the therapeutic outcome of tacrolimus in patients with refractory ulcerative colitis

Tacrolimus is now considered to be one of the main therapeutic options for refractory ulcerative colitis. Both cytochrome P‐450 3A5 (CYP3A5) and ATP‐binding cassette subfamily B member 1 (ABCB1) associated with tacrolimus metabolism are known to have several genetic polymorphisms. However, it remains controversial whether these polymorphisms affect the therapeutic efficacy for ulcerative colitis. We aimed to investigate the influence of both CYP3A5 and ABCB1 polymorphisms on the efficacy of tacrolimus in ulcerative colitis treatment under the tight dose‐adjusting strategy.