Tacrolimus Dose Optimization Strategy for Refractory Ulcerative Colitis Based on the Cytochrome P450 3A5 Polymorphism Prediction Using Trough Concentration after 24 Hours.

BACKGROUND: In the tacrolimus treatment for refractory ulcerative colitis (UC), dose adjustment is necessary because the required doses to keep appropriate drug concentrations are significantly different among individuals. Cytochrome P450 (CYP) 3A5 polymorphism affects tacrolimus blood concentrations. However, it is difficult to obtain genetic information in real clinical practice. In the present study, we investigated possible factors that may predict CYP3A5 polymorphism and proposed a dose optimization strategy based on the obtained predicting factors. SUMMARY: We retrospectively analyzed 41 patients who underwent remission induction therapy with tacrolimus for UC in our hospital. First, we performed a correlation analysis of CYP3A5 polymorphism and pharmacokinetics. In the CYP3A5 non-expressers, the dose of tacrolimus (mg/kg) was lower and dose-adjusted trough levels (ng/mL per mg/kg) were higher compared with those in expressers. Next, we investigated factors that could predict CYP3A5 polymorphism. Trough concentration 24 h following tacrolimus administration was extracted as a significant factor. When the trough cutoff value at 24 h was set to 2.6 ng/mL, sensitivity and specificity for estimation of CYP3A5 polymorphism were 63 and 96% respectively. Therefore, when the trough concentration 24 h after administration is ≤2.6 ng/mL, the patient can be estimated as a CYP3A5 expresser and an increase in dose should be proposed. Key Message: The trough concentration 24 h after the first tacrolimus administration appears to be a useful predictor of -CYP3A5 polymorphism. Performing dose optimization strategy based on the prediction of CYP3A5 polymorphism can lead to earlier and safer remission induction.

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

BACKGROUND AND AIM: 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. METHODS: Sixty-one Japanese patients with ulcerative colitis treated with tacrolimus were enrolled retrospectively. Tacrolimus treatment was performed using the tight dose-adjusting strategy. Genotyping for CYP3A5*3, ABCB1 1236C>T, 2677G>A,T, and 3435C>T were performed, and the clinical outcomes at 12 weeks after the initiation of tacrolimus were compared among the genotypes. RESULTS: There was no association between the CYP3A5 genotypes and therapeutic efficacy. In contrast, a significant association was observed with the ABCB1 1236C > T polymorphism and therapeutic efficacy. The ABCB1 1236CC+CT groups (n = 41) had a significantly higher response rate (73% vs 35%; P = 0.004) and remission rate (61% vs 20%; P = 0.002) than the TT group (n = 20). The multivariate logistic regression analysis also revealed that ABCB1 1236C>T was identified as an independent factor associated with remission. CONCLUSIONS: ABCB1 1236C>T polymorphism significantly affects the therapeutic efficacy of tarcolimus at 12 weeks under the tight dose-adjusting treatment for ulcerative colitis.

TNFSF15 transcripts from risk haplotype for Crohn's disease are overexpressed in stimulated T cells.

TNFSF15 is a susceptibility gene for Crohn's disease (CD). It remains to be elucidated how the associated single nucleotide polymorphisms (SNPs) in TNFSF15 affect the susceptibility to CD. Because there are no non-synonymous SNPs in TNFSF15, we speculated that one or more of the SNPs associated with CD may act as cis-regulatory SNPs. To reveal the effects of the SNPs on the transcriptional activity of TNFSF15, we first examined the allelic expression imbalance of TNFSF15 in peripheral blood mononuclear cells (PBMCs). When PBMCs stimulated by phytohemagglutinin (PHA) were examined, the allelic ratio of mRNA transcribed from the risk haplotype to the non-risk haplotype increased, compared with the ratio without stimulation. When peripheral blood T cells and Jurkat cells stimulated by phorbol 12-myristate 13-acetate + ionomycin were examined, an allelic expression imbalance similar to that observed in PBMCs stimulated by PHA was confirmed. The promoter assay in stimulated Jurkat cells showed that the luciferase activity of the promoter region (-979 to +35) of the risk haplotype was significantly higher than that of the non-risk haplotype, and deletion and mutagenesis analysis demonstrated that this difference resulted from the -358T/C SNP. The promoter activity of -358C (risk allele) was higher than that of -358T (non-risk allele) in stimulated T cells. This effect of -358T/C on the transcriptional activity in stimulated T cells may confer susceptibility to CD.

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.

Correction: Allele-specific DNA methylation of disease susceptibility genes in Japanese patients with inflammatory bowel disease.

[This corrects the article DOI: 10.1371/journal.pone.0194036.].

A Genome-wide Association Study Identifying RAP1A as a Novel Susceptibility Gene for Crohn's Disease in Japanese Individuals.

BACKGROUND AND AIMS: Genome-wide association studies [GWASs] of European populations have identified numerous susceptibility loci for Crohn's disease [CD]. Susceptibility genes differ by ethnicity, however, so GWASs specific for Asian populations are required. This study aimed to clarify the Japanese-specific genetic background for CD by a GWAS using the Japonica array [JPA] and subsequent imputation with the 1KJPN reference panel. METHODS: Two independent Japanese case/control sets (Tohoku region [379 CD patients, 1621 controls] and Kyushu region [334 CD patients, 462 controls]) were included. GWASs were performed separately for each population, followed by a meta-analysis. Two additional replication sets [254 + 516 CD patients and 287 + 565 controls] were analysed for top hit single nucleotide polymorphisms [SNPs] from novel genomic regions. RESULTS: Genotype data of 4 335 144 SNPs from 713 Japanese CD patients and 2083 controls were analysed. SNPs located in TNFSF15 (rs78898421, Pmeta = 2.59 × 10-26, odds ratio [OR] = 2.10), HLA-DQB1 [rs184950714, pmeta = 3.56 × 10-19, OR = 2.05], ZNF365, and 4p14 loci were significantly associated with CD in Japanese individuals. Replication analyses were performed for four novel candidate loci [p <1 × 10-6], and rs488200 located upstream of RAP1A was significantly associated with CD [pcombined = 4.36 × 10-8, OR = 1.31]. Transcriptome analysis of CD4+ effector memory T cells from lamina propria mononuclear cells of CD patients revealed a significant association of rs488200 with RAP1A expression. CONCLUSIONS: RAP1A is a novel susceptibility locus for CD in the Japanese population.

Allele-specific DNA methylation of disease susceptibility genes in Japanese patients with inflammatory bowel disease.

BACKGROUND: Inflammatory bowel disease (IBD) has an unknown etiology; however, accumulating evidence suggests that IBD is a multifactorial disease influenced by a combination of genetic and environmental factors. The influence of genetic variants on DNA methylation in cis and cis effects on expression have been demonstrated. We hypothesized that IBD susceptibility single-nucleotide polymorphisms (SNPs) regulate susceptibility gene expressions in cis by regulating DNA methylation around SNPs. For this, we determined cis-regulated allele-specific DNA methylation (ASM) around IBD susceptibility genes in CD4+ effector/memory T cells (Tem) in lamina propria mononuclear cells (LPMCs) in patients with IBD and examined the association between the ASM SNP genotype and neighboring susceptibility gene expressions. METHODS: CD4+ effector/memory T cells (Tem) were isolated from LPMCs in 15 Japanese IBD patients (ten Crohn's disease [CD] and five ulcerative colitis [UC] patients). ASM analysis was performed by methylation-sensitive SNP array analysis. We defined ASM as a changing average relative allele score ([Formula: see text]) >0.1 after digestion by methylation-sensitive restriction enzymes. Among SNPs showing [Formula: see text] >0.1, we extracted the probes located on tag-SNPs of 200 IBD susceptibility loci and around IBD susceptibility genes as candidate ASM SNPs. To validate ASM, bisulfite-pyrosequencing was performed. Transcriptome analysis was examined in 11 IBD patients (seven CD and four UC patients). The relation between rs36221701 genotype and neighboring gene expressions were analyzed. RESULTS: We extracted six candidate ASM SNPs around IBD susceptibility genes. The top of [Formula: see text] (0.23) was rs1130368 located on HLA-DQB1. ASM around rs36221701 ([Formula: see text] = 0.14) located near SMAD3 was validated using bisulfite pyrosequencing. The SMAD3 expression was significantly associated with the rs36221701 genotype (p = 0.016). CONCLUSIONS: We confirmed the existence of cis-regulated ASM around IBD susceptibility genes and the association between ASM SNP (rs36221701) genotype and SMAD3 expression, a susceptibility gene for IBD. These results give us supporting evidence that DNA methylation mediates genetic effects on disease susceptibility.

Mapping of a disease susceptibility locus in the HLA region for Primary Biliary Cirrhosis in Japan.

AIMS: Primary biliary cirrhosis (PBC) is a chronic progressive cholestatic disease of unknown pathogenesis. However, several reports have demonstrated the involvement of genetic backgrounds in this syndrome. The aim of this study is to examine the genetic disequilibrium in the HLA region in Japanese patients using six microsatellite markers. METHODS: Genomic DNAs were obtained from 73 patients with PBC (patient cohort) and 186 healthy volunteers (control cohort). Genetic polymorphisms at six microsatellite markers (D6S1568, DQ.CAR, D6S273, TNF-d, C1-2-A, C3-2-11) were determined using fluorescence-labeled polymerase chain reaction (PCR) genetic analyzer. Allele frequencies were estimated by direct counting and the genotypic differentiation test was performed by the Markov chain method using Genepop software. RESULTS: Among these six microsatellite markers, four markers in the patients significantly (P < 0.05) deviated from the Hardy-Weinberg equilibrium: DQ.CAR (P = 0.0278), D6S273 (P = 0.0168), TNF-d (P = 0.0089) and C1-2-A (P = 0.0005). Genotypic differentiation test between the patients and controls demonstrated that DQ.CAR (P = 0.0111), TNF-d (P = 0.0051) and C1-2-A (P = 0.0371) were significant. Finally, allelic association test revealed before correction for multiple testing demonstrated allele125 of TNF-d (P = 0.00065, Pc = 0.0052) and allele246 of C1-2-A (P = 0.0026 Pc = 0.033) had significant association after Bonferroni's correction. CONCLUSION: Disequilibrium mapping using microsatellite markers was a useful method to narrow a disease susceptibility locus. The possible susceptibility gene in the HLA region is thought to be localized around or in the TNF gene. Further studies seem feasible using more closely distributed microsatellite markers or single nucleotide polymorphisms (SNPs) to narrow the susceptibility locus in PBC in Japanese populations.

Increased expression of IL12B mRNA transcribed from the risk haplotype for Crohn's disease is a risk factor for disease relapse in Japanese patients.

BACKGROUND: IL12B is a promising candidate for a susceptibility gene in Crohn's disease (CD). The aim of this study was to perform a candidate gene analysis of IL12B in Japanese CD patients, investigate whether the genotype is associated with disease phenotypes, and determine how the risk allele affects susceptibility to CD. METHODS: Three hundred seventy-five patients with CD, 265 patients with ulcerative colitis, and 463 healthy controls were examined. Ten single-nucleotide polymorphisms (SNPs) around IL12B were genotyped. Case-control and subphenotype (including disease course) analyses were performed. The allelic expression ratio of IL12B messenger RNA (mRNA) was examined by a SNaPshot analysis in lipopolysaccharide-stimulated monocytes. RESULTS: Four SNPs located upstream of the IL12B gene were significantly associated with CD. A conditional analysis revealed that these associations included two independent signals tagged by IL12B_1 and IL12B_3 (P = 9.42 × 10-6 and  1.49 × 10-4 respectively). IL12B_3 was also associated with earlier relapse in CD (P = 0.0144). The allelic expression ratios of IL12B mRNA transcribed from the risk haplotype to the protective haplotype tagged by IL12B_3 in lipopolysaccharide-stimulated monocytes from ten healthy controls heterozygous for IL12B_3 were significantly higher than that of the respective genomic DNA (P = 0.00923). No SNP was associated with ulcerative colitis. CONCLUSIONS: We confirmed the association of SNPs located upstream of IL12B with CD in Japanese patients. The demonstrated allelic expression imbalance supports the idea that the IL12B risk haplotype confers susceptibility not only to CD onset but to also relapse through increased IL12B mRNA expression.

Muramyl dipeptide and toll-like receptor sensitivity in NOD2-associated Crohn's disease.

Both NOD2 (CARD15) alleles are mutated in roughly 15% of patients with Crohn's disease, but functional effects are unclear. We analysed the cytokine response of peripheral blood mononuclear cells to muramyl dipeptide (MDP), the ligand for NOD2. MDP induced little TNFalpha or interleukin 1beta, but strong interleukin-8 secretion. MDP also substantially upregulated secretion of TNFalpha and interleukin 1beta induced by toll-like receptor ligands. These effects were abolished by the most common Crohn's NOD2 double mutant genotypes at low nanomolar MDP concentrations, and provide the basis to develop a test of NOD2 functional deficiency. In Crohn's disease, there are defects in neutrophil recruitment driven by NOD2 and interleukin 8 and in cross talk between the NOD2 and toll-like receptor pathways, which suggests that the immune system fails to receive an early priming signal.

Genotype and phenotype relation in inflammatory bowel disease.

Genotype-phenotype analysis helps us to discriminate among various subgroups of IBD and consequently helps us to understand the etiology and pathogenesis as well as develop effective treatments for each subgroup of IBD.

Polymorphisms in the estrogen receptor beta gene but not estrogen receptor alpha gene affect the risk of developing endometriosis in a Japanese population.

OBJECTIVE: To determine whether polymorphisms in the estrogen receptor (ER) alpha and beta genes are associated with endometriosis in a Japanese population. DESIGN: Association study. SETTING: University hospital. PATIENT(S): Japanese women diagnosed with endometriosis by laparotomy or laparoscopy. INTERVENTION(S): Determination of polymorphisms in the ERalpha and ERbeta genes was performed by polymerase chain reaction restriction fragment-length polymorphism analysis in 132 affected women and 182 controls. MAIN OUTCOME MEASURE(S): Frequency and distribution of AluI and RsaI polymorphisms in ERbeta gene and of PvuII and XbaI polymorphisms in ERalpha gene. RESULT(S): No significant differences in the frequency of either AluI and RsaI polymorphisms in the ERbeta gene or of XbaI and PvuII polymorphisms in the ERalpha gene were found between endometriosis patients and controls. However, a positive association was noted between the AluI polymorphism in the ERbeta gene and stage IV endometriosis patients in the population studied. CONCLUSION(S): The AluI polymorphism in the ERbeta gene is associated with an increased risk of stage IV endometriosis in a Japanese population.

Clinical course and longterm prognosis of Japanese patients with Crohn's disease: predictive factors, rates of operation, and mortality.

BACKGROUND: The purpose of this study was to clarify the long-term course of Crohn's disease (CD) and predictors of its prognosis in Japan. METHODS: This was a historical cohort study of 276 patients with CD who had been diagnosed between 1965 and 1998. The clinical course was evaluated by the course of the CD score (CCDS) according to the required treatments. The predictive factors were examined by stepwise regression test. The cumulative rates of operation and survival were calculated by the Kaplan-Meier method. RESULTS: Patients with colitis-type CD had significantly lower annual and cumulative operation rates than those with other types, and showed significantly better progress, estimated by the CCDS, than patients with ileocolitis type. Reliable predictors for the 2- to 5-year clinical course after starting treatment were the CCDS, the presence of laparotomy during the initial year, and onset at age 30 years or more. The predictors for the 6- to 10-year clinical course were the duration of symptoms at diagnosis and onset at age 16 years or less. The predictors for the 11- to 15-year clinical course were the CCDS, the maximum International Organization of the Study of Inflammatory Bowel Disease (IOIBD) assessment score during the first year after starting treatment, and the effectiveness of the initial treatment. Relative survival rates at 5, 10, 15, and 20 years after the onset were 98.9%, 98.1%, 97.7%, and 94.9%, respectively. CONCLUSIONS: CD patients with colitis type showed a better clinical course and had significantly different clinical features compared with the patients with ileitis and ileocolitis type. Prediction of the longterm course of CD is possible by using clinical factors during the first year after starting treatment. The relative survival rates in Japanese patients with CD are not different from those seen in Western countries. The purpose of this study was to clarify the long-term course of Crohn's disease (CD) and predictors of its prognosis in Japan.

Microsatellite instability and loss of heterozygosity in the nondysplastic colonic epithelium of ulcerative colitis.

Background. A major longterm risk for patients with ulcerative colitis (UC) is the development of colorectal dysplasia and cancer. Microsatellite instability (MI) has now been reported not only in colitic cancers but also in dysplasias, and even in nondysplastic inflamed mucosa. With the conventional microdissection technique, however, contamination by nonepithelial cells cannot be prevented and this could produce less reliable results than other methods. Therefore, we examined the condition of MI and loss of heterozygosity (LOH) of UC epithelium using a crypt isolation technique. Methods. One hundred and twenty-nine biopsy samples from 21 patients with UC were investigated for histology and microsatellite status, using nine microsatellite markers. A total of 1031 polymenase chain reaction (PCR) products were evaluated. Results. We found that no microsatellite markers displayed instability, but LOH at the 3p locus was detected in the nondysplastic epithelium of one patient with longstanding UC. Conclusions. Our study strongly suggests that MI does not contribute to the progression of the colitis-dysplasia sequence.

Polymorphism at codon 72 of the p53 gene is not associated with endometriosis in a Japanese population.

OBJECTIVE: Endometriosis is inherited as a complex trait, which means that multiple susceptibility genes interact with each other and the environment to produce the phenotype. Previous studies have implicated p53, a tumor suppressor gene, as a factor in the development of the disease. In a Japanese population, we investigated the frequency of the p53 polymorphism in women affected with endometriosis. METHODS: We compared the distribution of the p53 codon 72 polymorphism in endometriosis cases (n = 111) and population controls consisting of female neonates (n = 180) by using polymerase chain reaction restriction fragment-length polymorphism analysis in a Japanese population. RESULTS: The frequencies of the three p53 genotypes, Arginine (Arg)/Arg, Arg/Proline (Pro), and Pro/Pro in controls were 39.4%, 41.7%, and 18.9 %, respectively. The crude genotype frequencies in the endometriosis cases were similar to those of the controls (35.2%, 48.6%, and 16.2%, respectively). Using the Arg/Arg genotype as the reference, the odds ratios of the Arg/Pro and Pro/Pro genotypes were 1.30 (95% confidence interval [CI] 0.72-1.86, P =.33) and 0.96 (95% CI 0.47-1.94, P =.91), respectively. Thus, there were no significant differences in the frequency of the p53 codon 72 polymorphism between endometriosis cases and controls in this population. The endometriosis cases with severe disease only were also evaluated, but no significant difference was observed in the frequency of the polymorphism between this subgroup and the controls. CONCLUSION: Our findings suggest that the p53 codon 72 polymorphism is unlikely to be associated with endometriosis in Japanese women.

Correlative polymorphism of NAD(P)H: quinone oxidoreductase (NQO1) with telomere shortening in colorectal cancer.

AIM: The aim of this study was to examine whether and relationships could be found among polymorphism of the NQO1 gene, telomere length and telomerase activity in colorectal cancers. MATERIALS AND METHODS: Fifty-one invasive colorectal cancers were studied. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis was undergone to detect mutation of the NQO1 gene. Telomere length was examined by Southern blot analysis. Telomerase activity was assayed by telomeric repeat amplification protocol with minor modifications. RESULTS: Of the 51 tumors, 20 (39.2%) and 9 (17.6%) were heterozygous and homozygous for the mutation, respectively. Most of the cases homozygous for the mutation (88.9%) showed short telomeres and its frequency was significantly higher than in those heterozygous (p = 0.0432). However no relationship was found between the telomerase activity and mutation in the NQO1 gene. CONCLUSION: Our data suggest that oxidative stress by the lack of NQO1 activity could result in telomere shortening through colorectal cancinogenesis.

Multiparameter analysis for discreet differential diagnosis of mucosa-associated lymphoid tissue lymphoma in the intestine.

BACKGROUND: The diagnosis of mucosa-associated lymphoid tissue (MALT) lymphoma in the intestine is occasionally difficult from histological examination on small biopsy specimens obtained by endoscopy. This study focused on unusual cases of reactive lymphoproliferative disorders in the intestine in order to make a differential diagnosis of MALT lymphoma. MATERIALS AND METHODS: Five patients were examined with regards to clinical symptoms, endoscopic findings and multiparameter analysis (the morphological examination using routine hematoxylin and eosin staining by light microscopy, immunophenotyping by flow cytometry (FCM), immunohistochemistry and genotyping of extracted DNA). RESULTS: All cases showed an aggregation of lymphocytes and one case showed similar features to lymphoepithelial lesions. Analyses of FCM and genetic rearrangements denied the monoclonality in all cases. Consequently, we considered that all cases should be diagnosed as reactive lymphoid hyperplasia and inflammatory change. CONCLUSION: Multiparameter analysis is useful in making an exact diagnosis of MALT lymphoma and therefore contributes to prevent unnecessary overtreatment.

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 Crohn's disease. Elemental diet and total parenteral nutrition are effective therapies for Crohn's disease; however, changes of microbiota as a result of both treatments have not been fully elucidated. AIM: To elucidate changes of faecal microbiota in Crohn's disease patients treated with elemental diet and total parenteral nutrition. METHODS: Stool samples were collected from 33 active Crohn's 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 Crohn's 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 Crohn's disease patients was markedly different from healthy subjects. Species diversity was reduced by total parenteral nutrition, but not by elemental diet.

Increased expression of NKX2.3 mRNA transcribed from the risk haplotype for ulcerative colitis in the involved colonic mucosa.

NKX2.3 is a promising candidate for susceptibility genes to inflammatory bowel disease (IBD). The aim of this study was to perform a candidate gene analysis of NKX2.3 in Japanese IBD and to examine how the risk allele (haplotype) affects susceptibility to IBD using allelic expression ratios of NKX2.3 mRNA in the involved colonic mucosa. A total of 344 patients with Crohn's disease (CD), 253 patients with ulcerative colitis (UC), and 243 healthy controls (HCs) were genotyped for 3 tag-single nucleotide polymorphisms (SNPs; rs10883365, rs888208, and rs11596008) around NKX2.3. The allelic expression ratio of NKX2.3-mRNA was examined by TaqMan assay using rs888208 as an allelic (haplotypic) marker. Two SNPs (rs10883365 and rs888208) were significantly associated with UC (p = 7.79 × 10(-4), odds ratio [OR] = 1.54 [95% confidence interval (95% CI) 1.20-1.99], p = 7.70 × 10(-3), OR = 1.41 [95% CI 1.10-1.81], respectively) and 1 SNP (rs10883365) was associated with CD (p = 0.0366, OR = 1.29 [95% CI 1.02-1.63]). Haplotype B formed by the 3 SNPs demonstrated a significant association with UC (p = 6.11 × 10(-4), OR = 1.56 [95% CI 1.21-2.00]). Subgroup analyses indicated that rs10883365 was significantly associated mainly with colonic CD (p = 1.99 × 10(-3), OR = 1.91 [95% CI 1.27-2.88], vs HCs). The allelic expression ratios of NKX2.3 mRNA transcribed from haplotype B (risk haplotype) to haplotype A (the nonrisk haplotype) in the involved mucosa from 10 IBD patients were significantly higher than the allelic ratio of respective genomic DNA (p = 0.00195). We confirmed the association of SNP rs10883365 located in the 5' flanking region of NKX2-3 with Japanese UC and colonic CD and determined the risk haplotype (haplotype B) for UC. The demonstrated allelic expression imbalance supports the idea that the risk haplotype of NKX2.3 confers susceptibility to UC through increasing expression of NKX2.3 mRNA in the colonic mucosa.

Efficacy and safety of endoscopic balloon dilation for Crohn's strictures.

PURPOSE: This study was designed to investigate retrospectively the efficacy and safety of endoscopic balloon dilation for intestinal strictures in Crohn's disease. METHODS: Sixteen patients with 20 strictures were treated. The stricture sites were as follows: at the ileocolonic (n = 6) or ileoileal (n = 1) anastomosis, in the colon (n = 10), ileum (n = 2), and at the ileocecal valve (n = 1). The dilations were performed with through-the-scope balloons, with diameters of 15 to 20 mm on inflation and lengths of 30 to 80 mm. RESULTS: In 15 of 16 patients, the strictures were successfully dilated and the symptoms caused by the strictures disappeared after the first session. The patients were followed for a median of 38.5 months. Repeat symptomatic stricture formation occurred after a mean of 19.7 months in seven patients. Four patients needed second-round dilation and three patients were treated surgically. Complications occurred in four patients who had primary strictures: bleeding in one, high fever in one, and colorectal perforation in two. One of the patients complicated with colorectal perforation was treated surgically, and the other was treated conservatively. The cumulative nonsurgical rates for the dilation strictures were 93 percent at 12 months and 65 percent at 36 months, respectively. Three patients were treated surgically because of strictures or fistulas that were not related to the procedure of dilation. As a whole, the cumulative nonsurgical rates were 81 percent at 12 months and 46 percent at 36 months. Nine patients (56.3 percent) were able to avoid surgery. CONCLUSIONS: Using endoscopic balloon dilation, it may be possible to avoid or postpone surgery. Primary strictures seem to have increased risk of perforation.