Shenghong Zhang

Long noncoding RNA HOTAIR as an independent prognostic marker in cancer: a meta-analysis.

Background HOTAIR, a newly discovered long intergenic noncoding RNA (lincRNA), has been reported to be aberrantly expressed in many types of cancers. This meta-analysis summarizes its potential role as a biomarker in malignancy. Methods A quantitative meta-analysis was performed through a systematic search in Pubmed, Medline and Web of Science for eligible papers on the prognostic impact of HOTAIR in cancer from inception to Feb. 28, 2014. Pooled hazard ratios (HRs) with 95% confidence interval (95% CI) were calculated to summarize the effect. Results Nineteen studies were included in the study, with a total of 2033 patients. A significant association was observed between high HOTAIR expression and poor overall survival (OS) in patients with cancer (pooled HR 2.22, 95% CI: 1.68–2.93). Place of residence (Asian or Western countries), type of cancer (digestive or non-digestive disease), sample size (more or less than 100), and paper quality (score more or less than 85%) did not alter the significant predictive value of HOTAIR in OS from various kinds of cancer but preoperative status did. By combining HRs from Cox multivariate analyses, we found that HOTAIR expression was an independent prognostic factor for cancer patients (pooled HR 2.26, 95% CI: 1.62–3.15). Subgroup analysis showed that HOTAIR abundance was an independent prognostic factor for cancer metastasis (HR 3.90, 95% CI: 2.25–6.74). For esophageal carcinoma, high HOTAIR expression was significantly associated with TNM stage (III/IV vs. I/II: OR 6.90, 95% CI: 2.81–16.9) without heterogeneity. In gastric cancer, HOTAIR expression was found to be significantly associated with lymph node metastases (present vs. absent: OR 4.47, 95% CI: 1.88–10.63) and vessel invasion (positive vs. negative: OR 2.88, 95% CI: 1.38–6.04) without obvious heterogeneity. Conclusions HOTAIR abundance may serve as a novel predictive factor for poor prognosis in different types of cancers in both Asian and Western countries.

Epigenetic reprogramming reverses the malignant epigenotype of the MMP/TIMP axis genes in tumor cells.

Cancer progression is characterized by extensive tumor invasion into the surrounding extracellular matrix (ECM) and migration to metastatic sites. The increased proteolytic degradation of the ECM during tumor invasion is directly dependent on the activity of matrix metalloproteinases (MMPs), counter‐balanced by tissue inhibitors of matrix metalloproteinases (TIMPs). In this study, we found that unbalanced expression of MMP/TIMP axis genes in tumors was correlated with aberrant epigenotypes in the various gene promoters. The malignant epigenotypes could be therapeutically corrected by a simple defined factor‐mediated reprogramming approach. Correction of the abnormal epigenotypes by nuclear remodeling leads to a rebalance in the gene expression profile, an alteration in tumor cell morphology, attenuation of tumor cell migration and invasion in vitro, and reduced tumorigenicity in nude mice. We further identified the downregulation of the MKK‐p38 MAPK signal pathway as an important underlying mechanism for reduced tumorigenicity in this epigenetic reprogramming model. These data demonstrate that the malignant phenotypes seen in cancer can be corrected by a nuclear remodeling mechanism, thus highlighting a novel non‐chemotherapeutic, non‐radiotherapeutic approach for the treatment of cancer.

Pro-inflammatory miR-223 mediates the cross-talk between the IL23 pathway and the intestinal barrier in inflammatory bowel disease.

BackgroundThe IL23/Th17 pathway is essential for the onset of inflammatory bowel disease (IBD), yet the specific mechanism by which this pathway initiates the disease remains unknown. In this study, we identify the mechanisms that mediate cross-talk between the IL23 pathway and the intestinal barrier in IBD.ResultsThe downstream targets of the IL23 pathway were identified by RNA array profiling and confirmed by immunohistochemical staining. The role of miRNAs that interact with IL23 was explored in mice with TNBS-induced colitis. Claudin-8 (CLDN8), a multigene family protein that constitutes the backbone of tight junctions, was identified as a novel target of IL23 in IBD. CLDN8 was significantly downregulated in IBD patients with inflamed colonic mucosa, and in trinitrobenzene sulphonic acid (TNBS) induced colitis in mice. Therapeutic treatment of colitis in mice using an IL23 antibody restored CLDN8 abundance, in parallel with recovery from colitis. In addition, we identify miR-223 as a novel mediator of the crosstalk between the IL23 signal pathway and CLDN8 in the development of IBD. MiR-223 was upregulated in IBD, and its activity was regulated through the IL23 pathway. Antagomir inhibition of miR-223 reactivated CLDN8 and improved a number of signs associated with TNBS-induced colitis in mice.ConclusionsOur study characterizes a new mechanistic pathway in IBD, in which miR-223 interacts with the IL23 pathway by targeting CLDN8. Strategies designed to disrupt this interaction may provide novel therapeutic agents for the management of IBD.

Upregulation of miR-665 promotes apoptosis and colitis in inflammatory bowel disease by repressing the endoplasmic reticulum stress components XBP1 and ORMDL3

MicroRNAs are critical post-transcriptional regulators of gene expression and key mediators of pathophysiology of inflammatory bowel disease (IBD). This study is aimed to study the role of miR-665 in the progression of IBD. Real-time PCR analysis was used to determine miR-665 expression in 89 freshly isolated IBD samples and dextran sulfate sodium (DSS)-induced colonic mucosal tissues. The role of miR-665 in inducing apoptosis and colitis were examined by Annexin V, TUNEL (terminal deoxynucleotidyl transferase dUTP nick-end labeling) staining, colony formation in vitro and DSS-induced colitis mice model in vivo. Moreover, luciferase reporter assay, western blot analysis and microribonucleoprotein immunoprecipitation were performed to determine that miR-665 directly repressed XBP1 (X-box-binding protein-1) and ORMDL3 expression. Herein, our results revealed that miR-665 was markedly upregulated in active colitis. Gain-of-function and loss-of-function studies showed that ectopic expression of miR-665 promoted apoptosis under different inflammatory stimuli. Importantly, delivery of miR-665 mimic promoted, while injection of antagomiR-665 markedly impaired DSS-induced colitis in vivo. Mechanistically, we demonstrated that miR-665 induced apoptosis by inhibiting XBP1 and ORMDL3. Taken together, our findings reveal a new regulatory mechanism for ER stress signaling and suggest that miR-665 might be a potential target in IBD therapy.

Imbalances of CD4+ T-cell subgroups in Crohn's disease and their relationship with disease activity and prognosis

The CD4+ T‐cell subgroups play central pathophysiological roles in Crohns disease (CD); however, their clinical relevance requires additional clarification and remains controversial. We investigated their balance in Chinese CD patients and explored their clinical significance.

Role of Helicobacter species in Chinese patients with inflammatory bowel disease.

ABSTRACT Based on 16S rRNA gene PCR, no significant difference was observed in rates of detection of Helicobacter species in intestinal biopsy specimens from 160 Chinese inflammatory bowel disease (IBD) patients (10%) and 80 controls (6.3%). By using a [13C]urea breath test, the H. pylori infection rate in 208 Chinese IBD patients (19.7%) was found to be significantly lower than that in 416 controls (48.8%).

Systematic review with meta-analysis: loss of response and requirement of anti-TNFα dose intensification in Crohn’s disease

BackgroundTo review the frequency with which anti-TNF-α loses its effect and dose “intensification” is required for Crohn’s disease (CD) treatment.MethodsElectronic databases were searched for eligible studies. Raw data from studies meeting inclusion criteria were pooled for effect estimates. Subgroup analyses were performed for exploration of heterogeneity regarding all outcomes.ResultsEighty-six eligible studies were included. Estimates of loss of response (LOR) incidence ranged from 8 to 71%. The random effects pooled incidence of LOR with a median follow-up of 1-year was 33% (95% CI 29–38, 55 studies, n = 6135). The effect estimate based on data from patients with infliximab was 33% (95% CI 27-40), 30% (95% CI 22–39) for adalimumab, and 41% (95% CI 30–53) for certolizumabpegol. Overall, the mean percentage of patients’ LOR to anti-TNFs was 38.5%. The annual risk for LOR was 20.9% per patient-year. The random-effects pooled rate of need for dose intensification with a median follow-up of 1 year was 34% (95% CI 28–41, 38 studies, n = 10,690). The effect estimate for infliximab was 38% (95% CI 28–50), 36% (95% CI 30–43) for adalimumab, and 2% (95% CI 2–3) for certolizumab-pegol. The mean percentage of patients who needed an anti-TNF dose escalation was 23% with an annual risk of 18.5% per patient-year. There was no evidence of publication bias for incidence of LOR but not for the dose intensification (p = 0.001).ConclusionsOverall, around one-third of CD patients experience a LOR and required dose intensification in primary anti-TNF-α responders.

Opposite effects of interferon regulatory factor 1 and osteopontin on the apoptosis of epithelial cells induced by TNF-α in inflammatory bowel disease.

Background:Inflammatory bowel disease (IBD) is characterized by a damaged intestinal epithelium barrier. Interferon regulatory factor 1 (IRF1) and osteopontin (OPN) regulate cell survival and growth in a variety of circumstances but their effects on the intestinal epithelium have not been elucidated. In this study, we sought to determine the effects of OPN on intestinal epithelial cells under conditions of tumor necrosis factor (TNF)-&agr;–induced inflammation and whether IRF1 regulates OPN expression, the activation of downstream pathways, and inflammatory responses. Methods:The expression levels of OPN and IRF1 were assessed by immunohistochemical analyses of human IBD and experimental mouse colitis. The effects of IRF1 and OPN on inflammatory responses were investigated in vitro in NCM460 and Caco-2 cells stimulated by TNF-&agr;. Changes in p-AKT, p-P38, and p-ERK levels were quantified by western blotting assays. The regulation of OPN expression by IRF1 was determined by luciferase activity and chromatin immunoprecipitation assays. Results:IRF1 was upregulated in human IBD and in the colon epithelium of mice with dextran sulfate sodium–induced colitis. Additionally, IRF1 was correlated with high-sensitivity C-reactive protein, erythrocyte sedimentation rate, Crohns disease activity index, Crohns disease endoscopic index of severity, and simple endoscopic score for Crohns disease in Crohns disease and with high-sensitivity C-reactive protein, erythrocyte sedimentation rate, Mayo score, Baron score, modified Baron score, Rachmilewitz score, ulcerative colitis endoscopic index of severity, ulcerative colitis colonoscopic index of severity, and disease duration in ulcerative colitis. The expression of OPN was significantly decreased in patients with IBD compared with controls and in dextran sulfate sodium–induced experimental colitis and was also inversely correlated with clinical and endoscopic activities in both Crohns disease and ulcerative colitis. TNF-&agr; treatment upregulated IRF1 and diminished OPN in both NCM460 and Caco-2 cells. The overexpression of OPN and rhOPN ameliorated the apoptosis induced by TNF-&agr;, whereas the overexpression of IRF1 aggravated apoptosis, indicating opposite effects of OPN and IRF1 in inflamed epithelial cells. The luciferase and chromatin immunoprecipitation assays showed that IRF1 transcriptionally modulated the expression of OPN. TNF-&agr; inhibited the OPN-induced upregulation of p-ERK, p-P38, and p-AKT. Conclusions:Our data suggest that during intestinal inflammation, the TNF-&agr;–mediated activation of IRF1 is related to the subsequent suppression of OPN expression, further reducing p-AKT, p-P38, and p-ERK activities and resulting in aggravation of the injury to intestinal epithelial cells.

Circulating MicroRNA223 is a New Biomarker for Inflammatory Bowel Disease

Abstract Endoscopy is an important tool in screening and monitoring inflammatory bowel disease (IBD); however, it is invasive, costly, and associated with risks to the patients. Recently, circulating microRNAs (miRNAs) have emerged as promising noninvasive biomarkers. We proposed that the expression of serum microRNA223 (miR-223) could be a biomarker for IBD. Studies were conducted using serum samples from 100 patients with IBD (50 with Crohns disease [CD] and 50 with ulcerative colitis [UC]) and 50 healthy controls. The expression of serum miR-223 was measured by quantitative reverse transcription-polymerase chain reaction. The clinical disease activity was assessed by measurement of the Crohns disease activity index for CD and the Mayo score for UC. Endoscopies were performed and graded according to the simple endoscopic score for CD and the ulcerative colitis endoscopic index of severity scores for UC. Blood samples for the measurement of high-sensitivity C-reactive protein (hs-CRP) and erythrocyte sedimentation rate (ESR) were taken within 1 week before or after endoscopy. Serum miR-223 expression increased 2.2 times in patients with CD and 2.8 times in patients with UC compared with the control group. Most importantly, the level of serum miR-223 was correlated with several indicators of disease activity both in CD and UC. Serum miR-223 demonstrated a higher Spearman r value than ESR and hs-CRP in detecting the disease activity of patients with IBD. Serum miR-223 might be a promising biomarker for monitoring disease activity in IBD patients.

Effects of Combination Therapy With Immunomodulators on Trough Levels and Antibodies Against Tumor Necrosis Factor Antagonists in Patients With Inflammatory Bowel Disease: A Meta-analysis

BACKGROUND & AIMS: It is not clear whether combination therapy with immunomodulators affects the immunogenicity of tumor necrosis factor (TNF) antagonists in patients with inflammatory bowel disease. We performed a meta‐analysis to quantify the effects of combined immunomodulator therapy on the presence of antibodies against TNF antagonists (antidrug antibodies [ADAs]) and trough levels of anti‐TNF agents. METHODS: We systematically searched publication databases for studies that reported prevalence of ADAs in patients who received anti‐TNF agents. Raw data from studies that met the inclusion criteria were pooled to determine effect estimates. We performed subgroup and metaregression analyses to determine the level of heterogeneity among study outcomes. RESULTS: We analyzed findings from 35 studies that met inclusion criteria (results reported from 6790 patients with inflammatory bowel disease). The pooled risk ratio for formation of ADAs in patients receiving combined therapy with immunomodulators, versus that of patients receiving anti‐TNF monotherapy, was 0.49 (95% confidence interval, 0.41–0.59; P < .001). However, the pooled analysis did not demonstrate a significant difference in trough levels of anti‐TNF agents between patients with versus without concurrent use of immunomodulators (standardized mean difference, 0.11; 95% confidence interval, 0.19–0.41; P = .47). Subgroup analyses of patients treated with different TNF antagonists revealed no difference in the formation of ADAs (P = .50 for interaction); the protective effect of immunomodulators did not differ with type of drug patients were given (methotrexate vs thiopurines), or assay for ADA. We observed heterogeneity only among studies of patients with ulcerative colitis (I2 = 76%). Funnel plot and Egger test analyses indicated publication bias in the studies (P = .001). CONCLUSIONS: In a meta‐analysis of published studies, we associated combined treatment with immunomodulators with reduced risk of formation of antibodies against TNF antagonists in patients with inflammatory bowel disease.