Decoding the glycoproteome: a new frontier for biomarker discovery in cancer

Cancer early detection and treatment response prediction continue to pose significant challenges. Cancer liquid biopsies focusing on detecting circulating tumor cells (CTCs) and DNA (ctDNA) have shown enormous potential due to their non-invasive nature and the implications in precision cancer management. Recently, liquid biopsy has been further expanded to profile glycoproteins, which are the products of post-translational modifications of proteins and play key roles in both normal and pathological processes, including cancers. The advancements in chemical and mass spectrometry-based technologies and artificial intelligence-based platforms have enabled extensive studies of cancer and organ-specific changes in glycans and glycoproteins through glycomics and glycoproteomics. Glycoproteomic analysis has emerged as a promising tool for biomarker discovery and development in early detection of cancers and prediction of treatment efficacy including response to immunotherapies. These biomarkers could play a crucial role in aiding in early intervention and personalized therapy decisions. In this review, we summarize the significant advance in cancer glycoproteomic biomarker studies and the promise and challenges in integration into clinical practice to improve cancer patient care.

Warning signs from the crypt: Aberrant protein glycosylation marks opportunities for early colorectal cancer detection

ABSTRACT

Colorectal cancer (CRC) remains a leading cause of cancer-related deaths despite being the most preventable and treatable forms of cancer when caught early through screening. There is an unmet need for novel screening approaches with improved accuracy, less invasiveness, and reduced costs. In recent years, evidence has accumulated around particular biological events that happen during the adenoma to carcinoma transition, especially focusing on precancerous immune responses in the colonic crypt. Protein glycosylation plays a central role in driving those responses and recently numerous reports have been published on how aberrant protein glycosylation, both in colonic tissue and on circulating glycoproteins reflects these precancerous developments. The complex field of glycosylation, which exceeds complexity of proteins by several orders of magnitude, can now be studied primarily because of the availability of new high-throughput technologies like mass spectrometry and artificial-intelligence (AI)-powered data processing. This has now opened new avenues to studying novel biomarkers for CRC screening.This review summarizes the early events taking place from the normal colon mucosa towards adenoma and adenocarcinoma formation and associated critical protein glycosylation phenomena both on tissue level and in the circulation. These insights will help establish an understanding in the interpretation of novel CRC detection modalities that involve high throughput glycomics.

Autotaxin loss accelerates intestinal inflammation by suppressing TLR4-mediated immune responses

Autotaxin (ATX) converts lysophosphatidylcholine and sphingosyl-phosphorylcholine into lysophosphatidic acid and sphingosine 1-phosphate, respectively. Despite the pivotal function of ATX in lipid metabolism, mechanisms by which ATX regulates immune and inflammatory disorders remain elusive. Here, using myeloid cell lineage-restricted Atx knockout mice, we show that Atx deficiency disrupts membrane microdomains and lipid rafts, resulting in the inhibition of Toll-like receptor 4 (TLR4) complex formation and the suppression of adaptor recruitment, thereby inhibiting TLR4-mediated responses in macrophages. Accordingly, TLR4-induced innate immune functions, including phagocytosis and iNOS expression, are attenuated in Atx-deficient macrophages. Consequently, Atx^-/- mice exhibit a higher bacterial prevalence in the intestinal mucosa compared to controls. When combined with global Il10^-/- mice, which show spontaneous colitis due to the translocation of luminal commensal microbes into the mucosa, myeloid cell lineage-restricted Atx knockout accelerates colitis development compared to control littermates. Collectively, our data reveal that Atx deficiency compromises innate immune responses, thereby promoting microbe-associated gut inflammation.

Abstract LB-184: A lncRNA-histone acetyltransferase complex induces colorectal oncogenesis through regulation of a metabolic kinase network

Long non-coding RNAs (LncRNAs) through interactions with other cellular macromolecules drive cell processes contributing to important cancer phenotypes. Here we show that HOTAIR, a highly up-regulated lncRNA in human colon cancers, induces transformation of human non-transformed colon epithelial cells. An exon 6 HOTAIR region directly binds the histone acetyltransferase PCAF (KAT2B). The HOTAIR/PCAF complex regulates H3K27 acetylation and transcriptional activation preferentially of genes encoding components of the PI3K/AKT/MEK pathways and induces cell metabolic reprogramming. The transcriptional signature of this HOTAIR/PCAF metabolic circuit is active in colon cancer and correlates with overall patient survival. Topological and mechanistic analyses were employed to characterize the HOTAIR/PCAF interface and design a reversible specific inhibitor (CPDI-1). Selective blocking of the HOTAIR-PCAF interaction, suppresses AKT activation and tumor growth. In conclusion, we demonstrate that disruption of a lncRNA-histone modifier complex interferes with the cancer epigenome and represents a novel approach for cancer therapeutics.

Citation Format: Christos Polytarchou, Maria Hatziapostolou, Marina Koutsioumpa, Niki Christodoulou, Tung On Yau, Eleni Birli, Odette Pomenya, Cristina Montiel-Duarte, Swapna Mahurkar Joshi, Daniel W. Hommes, Hein W. Verspaget, Jun Yu, Dimitrios Iliopoulos. A lncRNA-histone acetyltransferase complex induces colorectal oncogenesis through regulation of a metabolic kinase network [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr LB-184.

The effects of inflammatory bowel disease on caregivers: significant burden and loss of productivity

Background

Caregiver burden is the emotional, physical, practical, and/or financial burden associated with taking care of a patient with a chronic condition. Limited literature on caregiver burden in Inflammatory Bowel Diseases (IBD) has accounted for some predictors, but its effect on work productivity (absenteeism and presenteeism) is unknown.

Methods

In a prospective study, patients and their respective caregivers were surveyed from November 2015 until July 2017. Data on demographics, work productivity, quality of life, disease activity, caregiver burden and productivity were collected. The burden on caregivers was assessed and associations between caregiver productivity and caregiver burden were analyzed. Additionally, predictors for caregiver burden were identified.

Results

One hundred two IBD patients and their respective caregiver were included. In total, 39% of IBD caregivers experienced burden. Caregivers with burden experienced significantly more absenteeism and presenteeism (65 and 85% respectively). Furthermore, 51% of caregivers felt that they should be doing more for their care recipient and felt they could do a better job at caregiving. Predictors of burden included race/ethnicity, history of fistulas, diagnosis of ulcerative colitis, higher caregiver education, and hours spent caregiving.

Conclusion

Caregivers with burden had significantly more productivity decrease compared to those without burden. Additionally, the majority of caregivers feel they should be providing more and better care for their recipients. The development of strategies to address caregiver’s distress and perceived burden when caring for IBD patients is warranted.

Long-term Evaluation of Allogeneic Bone Marrow-derived Mesenchymal Stromal Cell Therapy for Crohn's Disease Perianal Fistulas

BACKGROUND AND AIMS

The long-term safety and efficacy of allogeneic bone marrow-derived mesenchymal stromal cell [bmMSC] therapy in perianal Crohn's disease [CD] fistulas is unknown. We aimed to provide a 4-year clinical evaluation of allogeneic bmMSC treatment of perianal CD fistulas.

METHODS

A double-blind dose-finding study for local bmMSC therapy in 21 patients with refractory perianal fistulising Crohn's disease was performed at the Leiden University Medical Center in 2012-2014. All patients treated with bmMSCs [1 x 107 bmMSCs cohort 1, n = 5; 3 × 107 bmMSCs cohort 2, n = 5; 9 × 107 bmMSCs cohort 3, n = 5] were invited for a 4-year evaluation. Clinical events were registered, fistula closure was evaluated, and anti-human leukocyte antigen [HLA] antibodies were assessed. Patients were also asked to undergo a pelvic magnetic resonance imaging [MRI] and rectoscopy.

RESULTS

Thirteen out of 15 patients [87%] treated with bmMSCs were available for long-term follow-up. Two non-MSC related malignancies were observed. No serious adverse events thought to be related to bmMSC therapy were found. In cohort 2 [n = 4], all fistulas were closed 4 years after bmMSC therapy. In cohort 1 [n = 4] 63%, and in cohort 3 [n = 5] 43%, of the fistulas were closed, respectively. In none of the patients anti-HLA antibodies could be detected 24 weeks and 4 years after therapy. Pelvic MRI showed significantly smaller fistula tracts after 4 years.

CONCLUSIONS

Allogeneic bmMSC therapy for CD-associated perianal fistulas is also in the long-term a safe therapy. In bmMSC-treated patients, fistulas with closure at Week 24 were still closed after 4 years.

Clinical Pharmacokinetic and Pharmacodynamic Considerations in the Treatment of Inflammatory Bowel Disease

According to recent clinical consensus, pharmacotherapy of inflammatory bowel disease (IBD) is, or should be, personalized medicine. IBD treatment is complex, with highly different treatment classes and relatively few data on treatment strategy. Although thorough evidence-based international IBD guidelines currently exist, appropriate drug and dose choice remains challenging as many disease (disease type, location of disease, disease activity and course, extraintestinal manifestations, complications) and patient characteristics [(pharmaco-)genetic predisposition, response to previous medications, side-effect profile, necessary onset of response, convenience, concurrent therapy, adherence to (maintenance) therapy] are involved. Detailed pharmacological knowledge of the IBD drug arsenal is essential for choosing the right drug, in the right dose, in the right administration form, at the right time, for each individual patient. In this in-depth review, clinical pharmacodynamic and pharmacokinetic considerations are provided for tailoring treatment with the most common IBD drugs. Development (with consequent prospective validation) of easy-to-use treatment algorithms based on these considerations and new pharmacological data may facilitate optimal and effective IBD treatment, preferably corroborated by effectiveness and safety registries.

Long-term Outcome of Early Combined Immunosuppression Versus Conventional Management in Newly Diagnosed Crohn's Disease

BACKGROUND AND AIMS

Long-term outcomes of early combined immunosuppression [top-down] compared to conventional management [step-up] in recently diagnosed Crohn's disease [CD] are unknown. We aimed to investigate long-term outcomes of participants of the Step-up/Top-down-trial.

METHODS

Trial participants' medical records were reviewed retrospectively. For 16 semesters following the 2-year trial, we recorded: clinical activity, medication use, flares, hospitalization, surgery and fistulas. Colonoscopy reports were scored as: endoscopic remission, aphthous/small ulcers or large ulcers. The primary endpoint was the proportion of semesters in remission.

RESULTS

Data were available from 119/133 patients [step-up n = 60]. During a median follow-up of 8 years, clinical remission rates were similar (70% vs 73% [p = 0.85] in step-up and top-down patients, respectively). A shorter time to flare was observed in step-up patients [median five vs nine semesters, p = 0.01]. Cumulatively, 62% of step-up patients used corticosteroids compared to 41% of top-down patients [p = 0.02]. Anti-tumour necrosis factor [anti-TNF] use was higher in the step-up group [73% vs 54%, p = 0.04]. No differences were found in to time to CD hospitalization [respectively 13 vs 14 semesters, p = 0.30], new fistula [14 vs 15 semesters, p = 0.20] or CD surgery [14 vs 15 semesters, p = 0.25]. Mucosal healing 2 years after treatment was associated with a reduced anti-TNF use, but not with differences in other long-term outcomes. Endoscopic remission occurred at similar rates between groups.

CONCLUSIONS

Top-down treatment did not result in increased clinical remission during long-term follow-up, compared to step-up treatment. However, lower relapse rates and a reduced use of anti-TNF agents and corticosteroids were observed. No difference was found in rates of endoscopic remission, hospitalization, surgery or new fistulas.

Using insurance claims to predict and improve hospitalizations and biologics use in members with inflammatory bowel diseases

OBJECTIVE

Inflammatory Bowel Disease (IBD) is an inflammatory disorder of the gastrointestinal tract that can necessitate hospitalization and the use of expensive biologics. Models predicting these interventions may improve patient quality of life and reduce expenditures.

MATERIALS AND METHODS

We used insurance claims from 2011 to 2013 to predict IBD-related hospitalizations and the initiation of biologics. We derived and optimized our model from a 2011 training set of 7771 members, predicting their outcomes the following year. The best-performing model was then applied to a 2012 validation set of 7450 members to predict their outcomes in 2013.

RESULTS

Our models predicted both IBD-related hospitalizations and the initiation of biologics, with average positive predictive values of 17% and 11%, respectively - each a 200% improvement over chance. Further, when we used topic modeling to identify four member subpopulations, the positive predictive value of predicting hospitalization increased to 20%.

DISCUSSION

We show that our hospitalization model, in concert with a mildly-effective interventional treatment plan for members identified as high-risk, may both improve patient outcomes and reduce insurance expenditures.

CONCLUSION

The success of our approach provides a roadmap for how claims data can complement traditional medical decision making with personalized, data-driven predictive medicine.

The Xenobiotic Transporter Mdr1 Enforces T Cell Homeostasis in the Presence of Intestinal Bile Acids

CD4⁺ T cells are tightly regulated by microbiota in the intestine, but whether intestinal T cells interface with host-derived metabolites is less clear. Here, we show that CD4⁺ T effector (Teff) cells upregulated the xenobiotic transporter, Mdr1, in the ileum to maintain homeostasis in the presence of bile acids. Whereas wild-type Teff cells upregulated Mdr1 in the ileum, those lacking Mdr1 displayed mucosal dysfunction and induced Crohn's disease-like ileitis following transfer into Rag1^-/- hosts. Mdr1 mitigated oxidative stress and enforced homeostasis in Teff cells exposed to conjugated bile acids (CBAs), a class of liver-derived emulsifying agents that actively circulate through the ileal mucosa. Blocking ileal CBA reabsorption in transferred Rag1^-/- mice restored Mdr1-deficient Teff cell homeostasis and attenuated ileitis. Further, a subset of ileal Crohn's disease patients displayed MDR1 loss of function. Together, these results suggest that coordinated interaction between mucosal Teff cells and CBAs in the ileum regulate intestinal immune homeostasis.

Illness Perceptions and Outcomes in Patients with Inflammatory Bowel Disease: Is Coping a Mediator?

PURPOSE

Patients with inflammatory bowel disease (IBD) often experience severe impairment in different life domains. Psychological factors, such as illness perceptions and coping, may play a role in the adjustment to IBD as indicated by mental and physical health, activity, and work impairment. The present study aimed at examining the assumption of the Common Sense Model (CSM) that coping mediates the relationship between illness perceptions and adjustment in patients with IBD.

METHOD

In a cross-sectional design, 211 IBD patients (73 % Crohn's disease, 40 % male, mean age 42.9 ± 12.9 years) attending an outpatient clinic completed questionnaires assessing illness perceptions (IPQ-R), coping (CORS), mental and physical health (SF-36), as well as activity and work impairment (WPAI). Multiple mediation analyses were applied that allow estimating the total and direct effects of all illness perception dimensions and the indirect effects through all coping strategies on the illness outcomes simultaneously.

RESULTS

The analyses yielded significant direct effects of perceptions regarding the cyclical course, the chronic course, the severity of the consequences, the comprehensibility, and the emotional impact of IBD on study outcomes. Additionally, significant indirect effects were found for the perceptions regarding the severity of the consequences, the possibility of personal control, and the comprehensibility of IBD on mental and physical health as well as activity impairment through the use of one specific coping strategy, i.e., reduction of activity.

CONCLUSION

The results provide evidence for the assumptions of the CSM and suggest the importance of addressing illness perceptions and activity stimulation in quality health care for IBD patients.

Five-year Safety Data From ENCORE, a European Observational Safety Registry for Adults With Crohn's Disease Treated With Infliximab [Remicade®] or Conventional Therapy

BACKGROUND AND AIMS

The ENCORE registry aimed at comparing the long-term safety of Crohn's disease [CD] treatment with infliximab [Remicade®] and with conventional therapies in real-world clinical practice.

METHODS

The 5-year, prospective, observational ENCORE registry followed patients with CD in nine European countries, who received treatment with infliximab, conventional therapies, or switched to infliximab from conventional therapy. Adverse events [AEs] in pre-specified categories and serious AEs were recorded at least every 6 months of the 5-year observation period. Frequency of events was evaluated, and multivariable analyses using follow-up time [Cox proportion hazards model] and exposure time [Poisson regression] were used to identify risk factors for time to AEs in pre-specified categories.

RESULTS

Patients who received infliximab [N = 1541], conventional therapies [N = 1121], or switched to infliximab [N = 298] were followed for medians of 60.4, 55.6, and 42.5 months, respectively. Infliximab median exposure was 18.7 and 19.3 months in the infliximab and switched-to-infliximab groups, respectively. In time-to-event Cox proportion hazards [PH] analyses adjusting for confounders, infliximab [vs conventional therapy] was associated with serious infections (hazard ratio [HR] = 1.64, 95% confidence interval [CI]: 1.17, 2.31] and haematological conditions [HR = 2.91, CI: 1.51, 5.59], and not associated with lymphoproliferative disorders/malignancy [HR = 1.44, CI: 0.86, 2.42] or death [HR = 1.22, CI: 0.63, 2.36]. Prednisone use was associated with higher mortality [HR = 3.58, CI: 1.49, 8.61]. In exposure-adjusted Poisson regression analyses, infliximab was associated with lower mortality (risk ratio [[RR] 0.39, CI: 0.17, 0.88]).

CONCLUSIONS

Data from 5-year safety follow-up of patients with CD in the ENCORE registry demonstrate that infliximab [Remicade®] exposure is associated with increased risk of serious infections and haematological conditions, whereas mortality may be decreased.

The xenobiotic transporter Mdr1 permits T cell adaptation to mucosa-associated bile acids in the ileum

Intestinal CD4+ T helper (TH) cells are subject to extensive regulation by microbiota. By contrast, it is not known whether or how TH cells interface with other, host-derived intestinal metabolites. Here we show that bile acids directly regulate mucosal TH cell function in the distal small intestine (i.e., ileum) via the xenobiotic transporter, Mdr1. Using both Mdr1-dependent dye efflux and a novel CRISPR-generated Mdr1 reporter mouse, we show that wild type RORγt+IL-17A+ (Th17) and RORγt-IFNγ+ (Th1) cells upregulate Mdr1 expression upon migration into the ileum. By contrast, germline ablation or shRNAmir-mediated knockdown of Mdr1 in Th17 and Th1 cells results in local dysfunction in the ileum, and these cells transfer Crohn’s disease-like ileitis in Rag1−/− hosts. Mdr1 enforces Th17 and Th1 cell survival and limits pro-inflammatory cytokine (TNFα, IFNγ) expression in the presence of conjugated bile acids (CBAs), which are actively reabsorbed through the ileal mucosa as a function of enterohepatic bile acid circulation. Accordingly, genetic or pharmacologic blockade of ileal CBA reabsorption restores Mdr1-deficient Th17 and Th1 cell homeostasis in ilea of transferred Rag1−/− hosts and rescues ileitis. In addition, MDR1 loss-of-function is evident in both ileitis-prone (SAMP1/YitFc) mice, and a subset of ileal Crohn’s disease patients. These data indicate that coordinated, local and druggable interactions between mucosal TH cells and mucosa-associated bile acids in the ileum contribute to intestinal immune homeostasis.

Autologous hematopoietic stem cells for refractory Crohn's disease

INTRODUCTION

Autologous hematopoietic stem cells are gaining ground as an effective and safe treatment for treating severe refractory Crohn's disease (CD). Autologous hematopoietic stem cell therapy (AHSCT) induces resetting of the immune system by de novo regeneration of T-cell repertoire and repopulation of epithelial cells by bone-marrow derived cells to help patients achieve clinical and endoscopic remission. Areas covered: Herein, the authors discuss the use of AHSCT in treating patients with CD. Improvements in disease activity have been seen in patients with severe autoimmune disease and patients with severe CD who underwent AHSCT for a concomitant malignant hematological disease. Clinical and endoscopic remission has been achieved in patients treated with AHSCT for CD. The only randomized trial published to date, the ASTIC Trial, did not support further use of AHSCT to treat CD. Yet, critics of this trial have deemed AHSCT as a promising treatment for severe refractory CD. Expert opinion: Even with the promising evidence presented for HSCT for refractory CD, protocols need to be refined through the collaboration of GI and hemato-oncology professionals. The goal is to incorporate safe AHSCT and restore tolerance by delivering an effective immune 'cease fire' as a treatment option for severe refractory CD.

Is Stem Cell Therapy Ready for Prime Time in Treatment of Inflammatory Bowel Diseases?

Autologous hematopoietic stem cell transplantation (HSCT) and mesenchymal stromal cell therapy have been proposed for patients with refractory Crohn's disease (CD) and fistulizing CD, respectively. Will these highly advanced techniques be available only for select patients, at specialized centers, or is further clinical development justified, with the aim of offering widespread, more definitive therapeutic options for often very difficult to treat disease? Patients with CD who are eligible for HSCT have typically been failed by most approved therapies, have undergone multiple surgeries, and have coped with years of disease activity and poor quality of life. The objective of HSCT is to immediately shut down the immune response and allow the transplanted stem cells to develop into self-tolerant lymphocytes. For patients with fistulizing CD, mesenchymal stromal cell therapy deposits MSCs locally, into fistulizing tracts, to down-regulate the local immune response and induce wound healing. Recent trials have produced promising results for HSCT and mesenchymal stromal cell therapy as alternatives to systemic therapies and antibiotics for patients with inflammatory bowel diseases, but are these immunotherapies ready for prime time?

Development and Validation of an Inflammatory Bowel Diseases Monitoring Index for Use With Mobile Health Technologies

BACKGROUND & AIMS

Mobile health technologies are advancing rapidly as smartphone use increases. Patients with inflammatory bowel disease (IBD) might be managed remotely through smartphone applications, but no tools are yet available. We tested the ability of an IBD monitoring tool, which can be used with mobile technologies, to assess disease activity in patients with Crohn's disease (CD) or ulcerative colitis (UC).

METHODS

We performed a prospective observational study to develop and validate a mobile health index for CD and UC, which monitors IBD disease activity using patient-reported outcomes. We collected data from disease-specific questionnaires completed by 110 patients with CD and 109 with UC who visited the University of California, Los Angeles, Center for IBD from May 2013 through January 2014. Patient-reported outcomes were compared with clinical disease activity index scores to identify factors associated with disease activity. Index scores were validated in 301 patients with CD and 265 with UC who visited 3 tertiary IBD referral centers (in California or Europe) from April 2014 through March 2015.

RESULTS

We assessed activity of CD based on liquid stool frequency, abdominal pain, patient well-being, and patient-assessed disease control, and activity of UC based on stool frequency, abdominal pain, rectal bleeding, and patient-assessed disease control. The indices identified clinical disease activity with area under the receiver operating characteristic curve values of 0.90 in patients with CD and 0.91 in patients with UC. They identified endoscopic activity with area under the receiver operating characteristic values of 0.63 in patients with CD and 0.82 in patients with UC. Both scoring systems responded to changes in disease activity (P < .003). The intraclass correlation coefficient for test-retest reliability was 0.94 for CD and for UC.

CONCLUSIONS

We developed and validated a scoring system to monitor disease activity in patients with CD and UC that can be used with mobile technologies. The indices identified clinical disease activity with area under the receiver operating characteristic curve values of 0.9 or higher in patients with CD or UC, and endoscopic activity in patients with UC but not CD.

Etrolizumab for ulcerative colitis: the new kid on the block?

INTRODUCTION

Ulcerative colitis (UC) is a chronic inflammatory bowel disease of unknown etiology. Currently approved therapies include prednisone, TNF antagonists and anti-metabolites which often are ineffective and have frequent adverse effects. Consequently, UC patients are always at risk for developing serious complications that affect their quality of life. Therefore, new treatment options are required.

AREAS COVERED

This article discusses etrolizumab, its mechanism and the potential role it can have in the future of treating UC. Etrolizumab is a humanized monoclonal antibody that selectively blocks lymphocyte trafficking and retention in the gut. The safety and efficacy data was reviewed from all randomized placebo-controlled trials which evaluated etrolizumab for the treatment of UC.

EXPERT OPINION

Etrolizumab is an effective and well-tolerated drug for the treatment of UC. It appears to be a promising molecule that can benefit UC patients.

Informatics-Based Discovery of Disease-Associated Immune Profiles

Advances in flow and mass cytometry are enabling ultra-high resolution immune profiling in mice and humans on an unprecedented scale. However, the resulting high-content datasets challenge traditional views of cytometry data, which are both limited in scope and biased by pre-existing hypotheses. Computational solutions are now emerging (e.g., Citrus, AutoGate, SPADE) that automate cell gating or enable visualization of relative subset abundance within healthy versus diseased mice or humans. Yet these tools require significant computational fluency and fail to show quantitative relationships between discrete immune phenotypes and continuous disease variables. Here we describe a simple informatics platform that uses hierarchical clustering and nearest neighbor algorithms to associate manually gated immune phenotypes with clinical or pre-clinical disease endpoints of interest in a rapid and unbiased manner. Using this approach, we identify discrete immune profiles that correspond with either weight loss or histologic colitis in a T cell transfer model of inflammatory bowel disease (IBD), and show distinct nodes of immune dysregulation in the IBDs, Crohn’s disease and ulcerative colitis. This streamlined informatics approach for cytometry data analysis leverages publicly available software, can be applied to manually or computationally gated cytometry data, is suitable for any clinical or pre-clinical setting, and embraces ultra-high content flow and mass cytometry as a discovery engine.

Value redefined for inflammatory bowel disease patients: a choice-based conjoint analysis of patients' preferences

PURPOSE

Value-based healthcare is an upcoming field. The core idea is to evaluate care based on achieved outcomes divided by the costs. Unfortunately, the optimal way to evaluate outcomes is ill-defined. In this study, we aim to develop a single, preference based, outcome metric, which can be used to quantify overall health value in inflammatory bowel disease (IBD).

METHODS

IBD patients filled out a choice-based conjoint (CBC) questionnaire in which patients chose preferable outcome scenarios with different levels of disease control (DC), quality of life (QoL), and productivity (Pr). A CBC analysis was performed to estimate the relative value of DC, QoL, and Pr. A patient-centered composite score was developed which was weighted based on the stated preferences.

RESULTS

We included 210 IBD patients. Large differences in stated preferences were observed. Increases from low to intermediate outcome levels were valued more than increases from intermediate to high outcome levels. Overall, QoL was more important to patients than DC or Pr. Individual outcome scores were calculated based on the stated preferences. This score was significantly different from a score not weighted based on patient preferences in patients with active disease.

CONCLUSIONS

We showed the feasibility of creating a single outcome metric in IBD which incorporates patients' values using a CBC. Because this metric changes significantly when weighted according to patients' values, we propose that success in healthcare should be measured accordingly.

Intraluminal Injection of Mesenchymal Stromal Cells in Spheroids Attenuates Experimental Colitis

BACKGROUND AND AIMS

In recent years, mesenchymal stromal cells [MSCs] emerged as a promising therapeutic option for various diseases, due to their immunomodulatory properties. We previously observed that intraperitoneally injected MSCs in experimental colitis form spherical shaped aggregates. Therefore, we aggregated MSCs in vitro into spheroids and injected them intraluminally in mice with established colitis, to investigate whether these MSC spheroids could alleviate the colitis.

METHODS

We injected 0.5 x 10(6) MSCs in spheroids, 2.0 x 10(6) MSCs in spheroids, or phosphate-buffered saline [PBS] as a treatment control, via an enema in mice with established dextran sulphate sodium [DSS]-induced colitis. Body weight was measured daily and disease activity score was determined at sacrifice. Endoscopy was performed to evaluate mucosal healing. After sacrifice, both systemic and local inflammatory responses were evaluated.

RESULTS

Intraluminally injected MSC spheroids alleviated DSS-induced colitis, resulting in significantly less body weight loss and lower disease activity score at sacrifice when a high dose of MSC spheroids was administered. However, the percentage of mucosal lesions in the distal colon and endoscopy scores were not significantly lower after treatment with 2.0 x 10(6) MSCs in spheroids compared with PBS-treated mice. Systemic inflammation marker serum amyloid A [SAA] was significantly reduced after treatment with 2.0 x 10(6) MSCs in spheroids. In addition, local cytokine levels of IFN-ɣ, TNF-α, IL-6, and IL-17a, as well as numbers of macrophages and neutrophils, showed a clear decrease-though not always significant-after intraluminal injection of the MSC spheroids.

CONCLUSION

Intraluminally injected MSC spheroids at least partially attenuate experimental colitis, with fewer phagocytes and proinflammmatory cytokines, when a high dose of MSCs in spheroids was administered.

Stem cell-based therapies in inflammatory bowel disease: promises and pitfalls

Inflammatory bowel disease (IBD) is a chronic, often relapsing, condition that deeply impacts the quality of life for many patients. Although there have been significant advances in medical treatments, a large proportion of patients become refractory to available therapeutic options. Stem-cell therapy through hematopoietic stem cells (HSCs) or mesenchymal stem (stromal) cells (MSCs) is a promising therapeutic option for severe refractory cases especially when surgery is not feasible. In HSC transplantation, the objective is to destroy the 'autoreactive' immune cells responsible for disease chronicity, and to re-establish gut tolerance to gut microbes. In perianal Crohn's disease (CD), the objective is to deposit MSCs locally in fistulizing tracts to down-regulate the local immune response and induce wound healing. Results from upcoming and ongoing clinical trials will set the path of these novel therapeutic options that have the capability to successfully treat severe refractory Crohn's patients.

Classifying Back Pain and Peripheral Joint Complaints in Inflammatory Bowel Disease Patients: A Prospective Longitudinal Follow-up Study

BACKGROUND AND AIMS

Peripheral joint complaints [pJTC] and chronic back pain [CBP] are the most common extra-intestinal manifestations in patients with inflammatory bowel disease [IBD]. This prospective study evaluates variables associated with joint/back pain, including IBD disease activity.

METHODS

IBD patients with back pain ≥ 3 months and/or peripheral joint pain/swelling [n = 155], and IBD patients without joint complaints [n = 100; controls], were followed for a period of 1 year. Patients were classified as having SpondyloArthritis [SpA] according to several sets of criteria. Statistical analysis included logistic regression models and linear mixed model analysis.

RESULTS

Of the 155 patients with joint/back pain, 13 had chronic back pain, 80 peripheral joint complaints, and 62 axial and peripheral joint complaints. Smoking, female gender, and IBD disease activity were independently associated with IBD joint/back pain. The Assessment in Spondyloarthritis International Society criteria for axial and peripheral SpA were fulfilled in 12.3% of patients, with 9.7% [n = 15] receiving a rheumatological diagnosis of arthritis. During the 12-month follow-up, the majority of the patients reporting joint/back pain remained stable.

CONCLUSIONS

In our cohort, the majority of IBD patients reported joint/back pain and SpA was relatively common. To facilitate effective care, gastroenterologists should be aware of the various features of SpA to classify joint complaints and, by making use of an efficient referral algorithm, to refer CBP patients to the rheumatologist.

MicroRNA214 Is Associated With Progression of Ulcerative Colitis, and Inhibition Reduces Development of Colitis and Colitis-Associated Cancer in Mice

BACKGROUND & AIMS

Persistent activation of the inflammatory response contributes to the development of inflammatory bowel diseases, which increase the risk of colorectal cancer. We aimed to identify microRNAs that regulate inflammation during the development of ulcerative colitis (UC) and progression to colitis-associated colon cancer (CAC).

METHODS

We performed a quantitative polymerase chain reaction analysis to measure microRNAs in 401 colon specimens from patients with UC, Crohn's disease, irritable bowel syndrome, sporadic colorectal cancer, or CAC, as well as subjects without these disorders (controls); levels were correlated with clinical features and disease activity of patients. Colitis was induced in mice by administration of dextran sodium sulfate (DSS), and carcinogenesis was induced by addition of azoxymethane; some mice also were given an inhibitor of microRNA214 (miR214).

RESULTS

A high-throughput functional screen of the human microRNAome found that miR214 regulated the activity of nuclear factor-κB. Higher levels of miR214 were detected in colon tissues from patients with active UC or CAC than from patients with other disorders or controls and correlated with disease progression. Bioinformatic and genome-wide profile analyses showed that miR214 activates an inflammatory response and is amplified through a feedback loop circuit mediated by phosphatase and tensin homolog (PTEN) and PDZ and LIM domain 2 (PDLIM2). Interleukin-6 induced signal transducer and activator of transcription 3 (STAT3)-mediated transcription of miR214. A miR214 chemical inhibitor blocked this circuit and reduced the severity of DSS-induced colitis in mice, as well as the number and size of tumors that formed in mice given azoxymethane and DSS. In fresh colonic biopsy specimens from patients with active UC, the miR214 inhibitor reduced inflammation by increasing levels of PDLIM2 and PTEN.

CONCLUSIONS

Interleukin-6 up-regulates STAT3-mediated transcription of miR214 in colon tissues, which reduces levels of PDLIM2 and PTEN, increases phosphorylation of AKT, and activates nuclear factor-κB. The activity of this circuit correlates with disease activity in patients with UC and progression to colorectal cancer.

Allogeneic Bone Marrow-Derived Mesenchymal Stromal Cells Promote Healing of Refractory Perianal Fistulas in Patients With Crohn's Disease

BACKGROUND & AIMS

Patients with perianal fistulizing Crohn's disease have a poor prognosis because these lesions do not heal well. We evaluated the effects of local administration of bone marrow-derived mesenchymal stromal cells (MSCs) to these patients from healthy donors in a double-blind, placebo-controlled study.

METHODS

Twenty-one patients with refractory perianal fistulizing Crohn's disease were randomly assigned to groups given injections of 1 × 10(7) (n = 5, group 1), 3 × 10(7) (n = 5, group 2), or 9 × 10(7) (n = 5, group 3) MSCs, or placebo (solution with no cells, n = 6), into the wall of curettaged fistula, around the trimmed and closed internal opening. The primary outcome, fistula healing, was determined by physical examination 6, 12, and 24 weeks later; healing was defined as absence of discharge and <2 cm of fluid collection-the latter determined by magnetic resonance imaging at week 12. All procedures were performed at Leiden University Medical Center, The Netherlands, from June 2012 through July 2014.

RESULTS

No adverse events were associated with local injection of any dose of MSCs. Healing at week 6 was observed in 3 patients in group 1 (60.0%), 4 patients in group 2 (80.0%), and 1 patient in group 3 (20.0%), vs 1 patient in the placebo group (16.7%) (P = .08 for group 2 vs placebo). At week 12, healing was observed in 2 patients in group 1 (40.0%), 4 patients in group 2 (80.0%), and 1 patient in group 3 (20.0%), vs 2 patients in the placebo group (33.3%); these effects were maintained until week 24 and even increased to 4 (80.0%) in group 1. At week six, 4 of 9 individual fistulas had healed in group 1 (44.4%), 6 of 7 had healed in group 2 (85.7%), and 2 of 7 had healed in group 3 (28.6%) vs 2 of 9 (22.2%) in the placebo group (P = .04 for group 2 vs placebo). At week twelve, 3 of 9 individual fistulas had healed in group 1 (33.3%), 6 of 7 had healed in group 2 (85.7%), 2 of 7 had healed in group 3 (28.6%), and 3 of 9 had healed in the placebo group (33.3%). These effects were stable through week 24 and even increased to 6 of 9 (66.7%) in group 1 (P = .06 group 2 vs placebo, weeks 12 and 24).

CONCLUSIONS

Local administration of allogeneic MSCs was not associated with severe adverse events in patients with perianal fistulizing Crohn's disease. Injection of 3 × 10(7) MSCs appeared to promote healing of perianal fistulas. ClinicalTrials.gov ID NCT01144962.

Diminished expression of CRHR2 in human colon cancer promotes tumor growth and EMT via persistent IL-6/Stat3 signaling

BACKGROUND & AIMS

Chronic inflammation promotes development and progression of colorectal cancer (CRC). We explored the distribution of Corticotropin-Releasing-Hormone (CRH)-family of receptors and ligands in CRC and their contribution in tumor growth and oncogenic EMT.

METHODS

mRNA expression of CRH-family members was analyzed in CRC (N=56) and control (N=46) samples, 7 CRC cell lines and normal NCM460 cells. Immunohistochemical detection of CRHR2 was performed in 20 CRC and 5 normal tissues. Cell proliferation, migration and invasion were compared between Urocortin-2 (Ucn2)-stimulated parental and CRHR2-overexpressing (CRHR2+) cells in absence or presence of IL-6. CRHR2/Ucn2-targeted effects on tumor growth and EMT were validated in SW620-xenograft mouse models.

RESULTS

CRC tissues and cell lines showed decreased mRNA and protein CRHR2 expression compared to controls and NCM460, respectively. The opposite trend was shown for Ucn2. CRHR2/Ucn2 signaling inhibited cell proliferation, migration, invasion and colony formation in CRC-CRHR2+ cells. In vivo, SW620-CRHR2+ xenografts showed decreased growth, reduced expression of EMT-inducers and elevated levels of EMT-suppressors. IL-1b, IL-6 and IL-6R mRNAs where diminished in CRC-CRHR2+ cells, while CRHR2/Ucn2 signaling inhibited IL-6-mediated Stat3 activation, invasion, migration and expression of downstream targets acting as cell cycle- and EMT-inducers. Expression of cell cycle- and EMT-suppressors was augmented in IL-6/Ucn2-stimulated CRHR2+ cells. In patients, CRHR2 mRNA expression was inversely correlated with IL-6R and vimentin levels and metastasis occurrence, while positively associated with E-cadherin expression and overall survival.

CONCLUSIONS

CRHR2 downregulation in CRC supports tumor expansion and spread through maintaining persistent inflammation and constitutive Stat3 activation. CRHR2^low CRC phenotypes are associated with higher risk for distant metastases and poor clinical outcomes.

Value-based health care for inflammatory bowel diseases

Increasing healthcare costs worldwide put the current healthcare systems under pressure. Although many efforts have aimed to contain costs in medicine, only a few have achieved substantial changes. Inflammatory bowel diseases rank among the most costly of chronic diseases, and physicians nowadays are increasingly engaged in health economics discussions. Value-based health care [VBHC] has gained a lot of attention recently, and is thought to be the way forward to contain costs while maintaining quality. The key concept behind VBHC is to improve achieved outcomes per encountered costs, and evaluate performance accordingly. Four main components need to be in place for the system to be effective: [1] accurate measurement of health outcomes and costs; [2] reporting of these outcomes and benchmarking against other providers; [3] identification of areas in need of improvement based on these data and adjusting the care delivery processes accordingly; and [4] rewarding high-performing participants. In this article we will explore the key components of VBHC, we will review available evidence focussing on inflammatory bowel diseases, and we will present our own experience as a guide for other providers.

MicroRNA targeting for the therapy of colitis-associated colon cancer

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Background: Inflammatory Bowel Diseases (IBD) consist of ulcerative colitis (UC) and Crohn’s Disease (CD), which are characterized by activation of inflammatory responses. Patients with longstanding UC are at high risk of developing colorectal cancer. The identification of novel molecular targets with therapeutic potential for UC and UC-related dysplasia are of major importance. Methods: Using a high throughput functional suppressor screen of the human microRNAome, we identified microRNAs involved in the regulation nuclear factor kappa beta (NF-κB). We correlated microRNA expression levels with different clinicopathological parameters in 401 colonic specimens derived from patients with UC, CD, irritable bowel syndrome (IBS), sporadic colon cancer (CRC), colitis-associated cancer (CAC) and control subjects. Bioinformatic and molecular analyses were employed for the study of micoRNA-regulated signaling pathways. A microRNA specific chemical inhibitor was used to treat colonic biopsies ex vivo and murine CAC development in vivo. Results: The microRNA screen identified miR-214 as master regulator of NF-κB. MiR-214 levels are increased in colonic tissues from UC and CAC, but not from CD, IBS and CRC patients and positively correlate with UC disease activity and duration. STAT3 regulates miR-214 expression in colonocytes in vitro and STAT3 and miR-214 levels positively correlate in UC and CAC. MiR-214 regulates the expression of phosphatase and tensin homolog (PTEN) and PDZ and LIM domain 2 (PDLIM2) and both are decreased in colonic tissues of UC and CAC patients. MiR-214 is amplified through a feedback loop circuit and its overexpression increases the tumorigenic and invasive phenotype of colon cancer cells. A chemical miR-214 inhibitor perturbs this circuit in colonic biopsies from UC patients ex vivo while intracolonic delivery suppresses CAC growth in mice. Conclusions: Our findings demonstrate a gene controlling the inflammatory response specifically in UC and CAC. The miR-214 molecular circuit activity correlates with UC disease activity and duration. Activation of this circuit contributes to colitis-associated colon carcinogenesis, and its suppression has therapeutic potential for patients with UC-related dysplasia.

Treatment of bone loss in osteopenic patients with Crohn's disease: a double-blind, randomised trial of oral risedronate 35 mg once weekly or placebo, concomitant with calcium and vitamin D supplementation

OBJECTIVE

Osteoporosis and fractures are frequently encountered in patients with Crohn's disease. In order to prevent fractures, treatment with bone protecting drugs appears warranted early in the course of bone disease when bone loss is not yet prominent. We therefore aimed to demonstrate a beneficial effect on bone density of the bisphosphonate risedronate in osteopenic Crohn's disease patients.

METHODS

This double-blind, placebo-controlled randomised trial of risedronate with calcium and vitamin D supplementation was performed in osteopenic Crohn's disease patients. Patients were treated for 2 years with follow-up after 3 and after every 6 months. Disease characteristics and activity and bone turnover markers were assessed at all visits; dual x-ray absorptiometry was performed at baseline, 12 and 24 months; radiographs of the spine at baseline and 24 months.

RESULTS

Of 132 consenting patients, 131 were randomised (67 placebo and 64 risedronate). Patient characteristics were similar in both groups, although the risedronate group was slightly heavier (body mass index 24.3 vs 23.0 kg/m(2)). Bone mineral density at lumbar spine increased 0.04 g/cm(2) on average in the risedronate group versus 0.01 g/cm(2) in the placebo group (p=0.007). The mean increase in total hip bone mineral density was 0.03 versus 0.01 g/cm(2), respectively (p=0.071). Fracture prevalence and incidence were similar. Change of T-scores and concentrations of bone turnover markers were consistent with a beneficial effect of risedronate when compared with placebo. The effect of risedronate was primarily demonstrated in the first 12 months of treatment. No serious unexpected suspected adverse events were observed.

CONCLUSIONS

A 24-month treatment course with risedronate 35 mg once weekly, concomitant with calcium and vitamin D supplementation, in osteopenic Crohn's disease patients improved bone density at lumbar spine. NTR 163 Dutch Trial Register.

Genetic and microbial factors modulating the ubiquitin proteasome system in inflammatory bowel disease

OBJECTIVE

Altered microbiota composition, changes in immune responses and impaired intestinal barrier functions are observed in IBD. Most of these features are controlled by proteases and their inhibitors to maintain gut homeostasis. Unrestrained or excessive proteolysis can lead to pathological gastrointestinal conditions. The aim was to validate the identified protease IBD candidates from a previously performed systematic review through a genetic association study and functional follow-up.

DESIGN

We performed a genetic association study in a large multicentre cohort of patients with Crohn's disease (CD) and UC from five European IBD referral centres in a total of 2320 CD patients, 2112 UC patients and 1796 healthy controls. Subsequently, we did an extensive functional assessment of the candidate genes to explore their causality in IBD pathogenesis.

RESULTS

Ten single nucleotide polymorphisms (SNPs) in four genes were significantly associated with CD: CYLD, USP40, APEH and USP3. CYLD was the most significant gene with the intronically located rs12324931 the strongest associated SNP (p(FDR)=1.74e-17, OR=2.24 (1.83 to 2.74)). Five SNPs in four genes were significantly associated with UC: USP40, APEH, DAG1 and USP3. CYLD, as well as some of the other associated genes, is part of the ubiquitin proteasome system (UPS). We therefore determined if the IBD-associated adherent-invasive Escherichia coli (AIEC) can modulate the UPS functioning. Infection of intestinal epithelial cells with the AIEC LF82 reference strain modulated the UPS turnover by reducing poly-ubiquitin conjugate accumulation, increasing 26S proteasome activities and decreasing protein levels of the NF-κB regulator CYLD. This resulted in IκB-α degradation and NF-κB activation. This activity was very important for the pathogenicity of AIEC since decreased CYLD resulted in increased ability of AIEC LF82 to replicate intracellularly.

CONCLUSIONS

Our results reveal the UPS, and CYLD specifically, as an important contributor to IBD pathogenesis, which is favoured by both genetic and microbial factors.

Loss of SMAD4 alters BMP signaling to promote colorectal cancer cell metastasis via activation of Rho and ROCK

BACKGROUND & AIMS

SMAD4 frequently is lost from colorectal cancers (CRCs), which is associated with the development of metastases and a poor prognosis. SMAD4 loss is believed to alter transforming growth factor β signaling to promote tumor progression. However, SMAD4 is also a central component of the bone morphogenetic protein (BMP) signaling pathway, implicated in CRC pathogenesis by human genetic studies. We investigated the effects of alterations in BMP signaling on the invasive and metastatic abilities of CRC cells and changes in members in this pathway in human tumor samples.

METHODS

We activated BMP signaling in SMAD4-positive and SMAD4-negative CRC cells (HCT116, HT-29, SW480, and LS174T); SMAD4 was stably expressed or knocked down using lentiviral vectors. We investigated the effects on markers of epithelial-mesenchymal transition and on cell migration, invasion, and formation of invadopodia. We performed kinase activity assays to characterize SMAD4-independent BMP signaling and used an inhibitor screen to identify pathways that regulate CRC cell migration. We investigated the effects of the ROCK inhibitor Y-27632 in immunocompromised (CD-1 Nu) mice with orthotopic metastatic tumors. Immunohistochemistry was used to detect BMPR1a, BMPR1b, BMPR2, and SMAD4 in human colorectal tumors; these were related to patient survival times.

RESULTS

Activation of BMP signaling in SMAD4-negative cells altered protein and messenger RNA levels of markers of epithelial-mesenchymal transition and increased cell migration, invasion, and formation of invadopodia. Knockdown of the BMP receptor in SMAD4-negative cells reduced their invasive activity in vitro. SMAD4-independent BMP signaling activated Rho signaling via ROCK and LIM domain kinase (LIMK). Pharmacologic inhibition of ROCK reduced metastasis of colorectal xenograft tumors in mice. Loss of SMAD4 from colorectal tumors has been associated with reduced survival time; we found that this association is dependent on the expression of BMP receptors but not transforming growth factor β receptors.

CONCLUSIONS

Loss of SMAD4 from colorectal cancer cells causes BMP signaling to switch from tumor suppressive to metastasis promoting. Concurrent loss of SMAD4 and normal expression of BMP receptors in colorectal tumors was associated with reduced survival times of patients. Reagents that interfere with SMAD4-independent BMP signaling, such as ROCK inhibitors, might be developed as therapeutics for CRC.

Anti-TNF antibodies in inflammatory bowel disease: do we finally know how it works?

Tumor necrosis factor (TNF) is a central pro-inflammatory cytokine that regulates the expression of numerous signaling pathways implicated in the progression of the immunological reaction. Unraveling the importance of TNF on the pathogenesis of inflammatory bowel disease (IBD) promoted anti-TNF antibodies as novel therapeutic agents. Initially, the main hypothesis behind the clinical application of anti-TNF antagonists in the clinic was that they exert their effects solely through neutralization of TNF. Anti-TNF antibodies induce and maintain clinical remission in patients with minimal side-effects. However, the cellular and molecular mechanisms of actions of the anti-TNF antibodies remain unknown. Various mechanisms of action have been proposed such as activation of transmembrane TNF mediated reverse signaling, induction of apoptosis, pro-inflammatory cytokine down-regulation, complement dependent cytotoxicity, antibodydependent cell-mediated cytotoxicity, and finally activation of regulatory immune cells via interactions with the Fc receptors. The observed discrepancies in the clinical efficacies as well as the differences in the structure of the various TNF antagonists nourish the investigation for additional modes of function.

Repurposing miltefosine for the treatment of immune-mediated disease?

Miltefosine is an ether lipid that was initially developed for cancer treatment in the early 1980s. Miltefosine largely failed development for oncology, although it was approved for the topical treatment of breast cancer metastasis. It was subsequently discovered that miltefosine is a highly effective treatment of visceral Leishmaniasis, a parasitic disease that affects millions worldwide and causes an estimated 30,000 fatalities each year. Oral treatment with miltefosine is generally well tolerated and has relatively few adverse effects. The exact mechanism of action of miltefosine treatment is still under investigation. Its close resemblance to phospholipids allows it to be quickly taken up by cell membranes and affect related processes, such as lipid metabolism and signaling through lipid rafts. These processes play an important role in the immune response and it comes as no surprise that miltefosine has been successfully tested for the treatment of a number of immune-mediated diseases in preclinical models of disease. Drug repurposing of miltefosine for immune-mediated diseases may provide an opportunity to expand the limited number of drugs that are currently available for therapeutic use.

Magnetic resonance imaging of the hand joints in patients with inflammatory bowel disease and arthralgia: a pilot study

OBJECTIVES

To assess whether subclinical inflammatory changes are present on magnetic resonance imaging (MRI) in patients with inflammatory bowel disease (IBD) and arthralgia.

METHOD

In this pilot study, painful hand joints [metacarpophalangeal (MCP), proximal interphalangeal (PIP), and/or distal interphalangeal (DIP)] of 11 IBD patients (age 18-45 years) with continuous pain for > 6 weeks were scanned on a 1.5-T extremity MRI system. A control group of 11 IBD patients without joint pain who were matched for type and disease duration of IBD, gender, and age was included. All patients were clinically examined by a rheumatologist for the presence of pain and arthritis. Imaging was performed according to a standard arthritis protocol with intravenous contrast administration on the same day. Images (blinded for clinical information) were evaluated by two readers in consensus for the presence of joint fluid, synovitis, tenosynovitis, enthesitis, erosions, cartilage defects, and bone marrow oedema.

RESULTS

Enthesitis was seen in three hand joints (MCP 2, MCP 3, PIP 3) of 2/11 (18%) arthralgia patients and in none of the control group (p = 0.48). A small amount of subchondral bone marrow oedema was seen in the metacarpal head of two controls. No other abnormalities were observed.

CONCLUSIONS

Several young IBD patients with chronic hand pain had subclinical inflammation on MRI, which invites for further study in a larger group of patients.

Intrauterine exposure and pharmacology of conventional thiopurine therapy in pregnant patients with inflammatory bowel disease

OBJECTIVE

Several studies have demonstrated a favourable safety profile for thiopurine use for inflammatory bowel disease (IBD) during pregnancy. We performed a study in pregnant patients with IBD who were using thiopurines, in order to determine the influence of pregnancy on thiopurine metabolism and to assess intrauterine exposure of the fetus to thiopurines.

DESIGN

Female patients with IBD receiving steady-state thiopurines and planning a pregnancy were prospectively enrolled. 6-Thioguanine nucleotide (6-TGN) and 6-methylmercaptopurine (6-MMP) concentrations were determined, combined with routine laboratory tests, before, during and after pregnancy. Thiopurine metabolites were measured in umbilical cord blood immediately after delivery.

RESULTS

Thirty patients who were using azathioprine (28 patients, median dose 1.93 mg/kg) or mercaptopurine (two patients, doses 1.32 and 0.94 mg/kg) were included. During pregnancy, median 6-TGN decreased over time (p=0.001). while 6-MMP increased, without causing myelotoxicity or hepatotoxicity. After delivery, both 6-TGN and 6-MMP levels returned to preconception baseline levels. Fetal 6-TGN concentrations correlated positively with maternal 6-TGN levels (p<0.0001). No 6-MMP was detected in the newborns, except one born with pancytopenia and high alkaline phosphatase activity; the mother of this infant had severe pre-eclampsia. All infants had normal Apgar scores, but 60% had anaemia at birth. No major congenital abnormalities were observed.

CONCLUSIONS

Pregnancy has a major effect on maternal thiopurine metabolism. In utero the unborn child is exposed to 6-TGN, but not to 6-MMP. Sixty per cent of the infants were born with anaemia, which raises the question whether infants should be tested for possible anaemia immediately after birth.

Oestrogens promote tumorigenesis in a mouse model for colitis-associated cancer

BACKGROUND

Hormone replacement therapy increases the risk of developing ulcerative colitis in postmenopausal women. Chronic intestinal inflammation predisposes to colon cancer development, but effects of female hormones on colitis-associated cancer development have not been examined.

AIM

To investigate the role of female hormones in the dextran sodium sulfate (DSS)-azoxymethane (AOM) mouse model for colitis-associated cancer.

DESIGN

We performed ovariectomies, or sham operations, on mice, and supplemented these animals with indicated hormones. Additionally, we used oestrogen receptor α or β (Erα or Erβ) mutant mice. To study colitis or colitis-associated cancer, we used DSS only, or DSS and AOM, respectively.

RESULTS

Ovariectomy protects female mice against colitis-associated tumour development. Hormone replacement in ovariectomised mice with either oestradiol (E2), medroxyprogesterone acetate or a combination of both suggests that oestrogens are the ovary-derived factor that promotes tumour development in the context of inflammatory damage. E2-treated animals showed increased clinical symptoms and Il-6 production upon DSS-induced colitis and enhanced epithelial proliferation. Treatment with E2 markedly increased the numbers of polyps in ovariectomised mice and also strongly promoted tumour progression with all E2-treated animals developing at least one invasive adenocarcinoma, whereas, placebo-treated animals developed adenomas only. Using Er mutant mice, we find that the protumorigenic effect of oestrogen depends on both Erα and Erβ.

CONCLUSIONS

Our results suggest that oestrogens promote inflammation-associated cancer development by impairing the mucosal response to inflammatory damage.

Adalimumab combined with ciprofloxacin is superior to adalimumab monotherapy in perianal fistula closure in Crohn's disease: a randomised, double-blind, placebo controlled trial (ADAFI)

OBJECTIVE

To assess whether a combination of adalimumab and ciprofloxacin is superior to adalimumab alone in the treatment of perianal fistulising Crohn's disease (CD).

DESIGN

Randomised, double-blind, placebo controlled trial in eight Dutch hospitals. In total, 76 CD patients with active perianal fistulising disease were enrolled. After adalimumab induction therapy (160/80 mg week 0, 2), patients received 40 mg every other week together with ciprofloxacin 500 mg or placebo twice daily for 12 weeks. After 12 weeks, adalimumab was continued. Follow-up was 24 weeks. Primary endpoint (clinical response) was defined as 50% reduction of fistulas from baseline to week 12. Secondary endpoints included remission (closure of all fistulas), Perianal Crohn's Disease Activity Index, Crohn's Disease Activity Index (CDAI) and Inflammatory Bowel Disease Questionnaire (IBDQ).

RESULTS

Clinical response was observed in 71% of patients treated with adalimumab plus ciprofloxacin and in 47% treated with adalimumab plus placebo (p=0.047). Likewise, remission rate at week 12 was significantly higher (p=0.009) in the combination group (65%) compared with adalimumab plus placebo (33%). Combination treatment was associated with a higher mean CDAI change and mean IBDQ change at week 12 (p=0.005 and p=0.009, respectively). At week 24, no difference in clinical response between the two treatment groups was observed (p=0.22). No difference in safety issues was observed.

CONCLUSIONS

Combination therapy of adalimumab and ciprofloxacin is more effective than adalimumab monotherapy to achieve fistula closure in CD. However, after discontinuation of antibiotic therapy, the beneficial effect of initial coadministration is not maintained.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT00736983.

The course of inflammatory bowel disease during pregnancy and postpartum: a prospective European ECCO-EpiCom Study of 209 pregnant women

BACKGROUND

The impact of pregnancy on the course of IBD is still controversial.

AIM

To investigate the impact of pregnancy on IBD and to search for factors with potential impact on remission.

METHODS

Pregnant IBD women from 12 European countries were enrolled between January 2003 and December 2006 and compared at conception (1:1) with nonpregnant IBD women. Data on disease course were prospectively collected at each trimester during pregnancy and in the postpartum (6 months) using a standardised questionnaire.

RESULTS

A total of 209 pregnant IBD women were included: 92 with Crohn's disease (CD; median age 31 years, range 17-40) and 117 with ulcerative colitis (UC; median age 32 years, range 19-42). No statistically significant difference in disease course during pregnancy and postpartum was observed between pregnant and nonpregnant CD women. Longer disease duration in CD and immunosuppressive therapy were found to be risk factors for activity during pregnancy. Pregnant UC women were more likely than nonpregnant UC women to relapse both during pregnancy (RR 2.19; 95% CI: 1.25-3.97, 0.004) and postpartum (RR 6.22; 95% CI: 2.05-79.3, P = 0.0004). During pregnancy, relapse was mainly observed in the first (RR 8.80; 95% CI 2.05-79.3, P < 0.0004) and the second trimester (RR 2.84, 95% CI 1.2-7.45, P = 0.0098).

CONCLUSIONS

Pregnant women with Crohn's disease had a similar disease course both during pregnancy and after delivery as the nonpregnant women. In contrast, pregnant women with ulcerative colitis were at higher risk of relapse during pregnancy and in the postpartum than nonpregnant ulcerative colitis women.

Impaired autophagy leads to abnormal dendritic cell-epithelial cell interactions

BACKGROUND AND AIMS

Dendritic cells (DC) are key players in intestinal immunity, as these cells can direct the immune response to either a tolerogenic or an immunogenic phenotype. In the intestine, DC sample and process luminal antigens by protruding dendrites through the epithelial cell layer. At the same time barrier integrity is maintained through the continuous formation of tight junctions. Aberrations in these interactions may lead to altered antigen sampling and improper immune responses. We have recently shown that autophagy, a process implicated in the pathogenesis of Crohn's disease, regulates cellular interactions in the context of DC and T cells. In this study we aimed to determine whether autophagy also regulates DC-epithelial cell interactions and whether this influences the ensuing immune response.

METHODS

DC were generated from peripheral blood monocytes of healthy volunteers. For interaction studies, DC were co-cultured with intestinal epithelial cells on the baso-lateral side of a transwell insert. Modulation of autophagy was achieved using atg16l1 specific siRNA or pharmacological inhibitors. Intraepithelial protrusion of dendrites was determined by confocal microscopy. Luminal sampling and DC activation status were analyzed by flow cytometry. Protein expression was measured by immunoblotting and cytometric bead assay.

RESULTS

Adhesion molecules E-cadherin and occludin partly localized to autophagosomes and increased autophagy resulted in decreased levels of these proteins. Reduced autophagy in either DC, epithelial cells or both resulted in the decreased formation of transepithelial protrusions by DC as well as a reduction in antigen sampling. Moreover, when autophagy was inhibited in the co-culture model, DC expressed increased levels of HLA-DR and costimulatory molecule CD86. Furthermore, decreased levels of autophagy resulted in lower IL-10 production by DC and these cells induced significantly more T-cell proliferation in an allogeneic mixed lymphocyte reaction.

CONCLUSIONS

In intestinal DC-epithelial cell interactions, autophagy deficiency leads to decreased antigen sampling, increased DC maturation and a more pro-inflammatory type of DC.

A rapid assay for on-site monitoring of infliximab trough levels: a feasibility study

Monitoring levels of biologicals against tumor necrosis factor (TNF) has been suggested to improve therapeutic outcomes in inflammatory bowel diseases (IBDs). This pilot study describes a rapid lateral flow (LF)-based assay for on-site monitoring of serum trough levels of humanized monoclonal antibody infliximab (IFX). The applied chromatographic method utilizes sequential flows of diluted serum, wash buffer, and an immunoglobulin generic label on LF strips with a Test line comprised of TNF-α. The successive flows permitted enrichment of IFX at the Test line before the label was applied. The label, luminescent upconverting phosphor (UCP) particles coated with protein-A, emits a 550-nm visible light upon excitation with 980-nm infrared light. IFX concentrations were determined through measurement of UCP fluorescence at the Test line. The assay was optimized to detect IFX levels as low as 0.17 μg/mL in serum. For patients with IBD, this limit is appropriate to detect levels associated with loss of response (0.5 μg IFX/mL). The assay was evaluated with clinical samples from patients with Crohn's disease and correlated well within the physiologically relevant range from 0.17 to 10 μg/mL with an IFX-specific ELISA. Performance of the assay was further successfully validated with samples from blood donors, IFX negative IBD patients, and rheumatoid arthritis patients that had developed anti-IFX antibodies. Because of its generic nature, the assay is suited for detecting most therapeutic anti-TNF-α monoclonal antibodies.

Subgroup analysis of the placebo-controlled CHARM trial: increased remission rates through 3 years for adalimumab-treated patients with early Crohn's disease

BACKGROUND AND AIMS

We examined the impact of disease duration on clinical outcomes and safety in a post hoc analysis of a remission maintenance trial with adalimumab in patients with moderate to severe CD.

METHODS

Patients in the CHARM trial were divided into 3 disease duration categories: <2 (n=93), 2 to <5 (n=148), and ≥5 years (n=536). Clinical remission and response rates at weeks 26 and 56 were compared between adalimumab and placebo subgroups, and assessed through 3 years of adalimumab treatment in the ADHERE follow-on trial. Logistic regression assessed the effect of disease duration and other factors on remission and safety.

RESULTS

At week 56, clinical remission rates were significantly greater for adalimumab-treated versus placebo-treated patients in all 3 duration subgroups (19% versus 43% for <2 years; P=0.024; 13% versus 30% for 2 to <5 years; P=0.028; 8% versus 28% for ≥5 years, P<0.001). Logistic regression identified shorter duration as a significant predictor for higher remission rate in adalimumab-treated patients. Patients with disease duration <2 years maintained higher remission rates than patients with longer disease duration through 3 years of treatment. The incidence of serious adverse events in adalimumab-treated patients was lowest with disease duration <2 years.

CONCLUSIONS

Adalimumab was superior to placebo for maintaining clinical remission in patients with moderately to severely active CD after 1 year of treatment regardless of disease duration. Clinical remission rates through 3 years of treatment were highest in the shortest disease duration subgroup in adalimumab-treated patients, with a trend to fewer side effects.

5-Aminosalicylic acid inhibits cell cycle progression in a phospholipase D dependent manner in colorectal cancer

BACKGROUND

5-Aminosalicylic acid (5-ASA) may protect against the development of inflammation-associated colorectal cancer. In vitro data suggest that, in colorectal cancer cells, 5-ASA induces cell cycle arrest, but the molecular mechanism leading to this arrest remains to be determined.

AIM

To dissect the signal transduction events that lead to 5-ASA mediated inhibition of proliferation of colorectal cancer cells, focusing on mammalian target of rapamycin (mTOR), a regulator of cell cycle progression.

METHODS

The influence of 5-ASA on mTOR signalling was examined in a panel of colorectal cancer cell lines. The effects of 5-ASA on the pathways that control mTOR activity were studied in detail in two different colorectal cancer cell lines, using western blot, siRNA, a phospholipase D (PLD) activity assay, proliferation assays and cell cycle analysis. The phosphorylation status of mTOR and its downstream target, ribosomal protein S6, was studied in colorectal cancers before and after topical 5-ASA treatment.

RESULTS

Treatment of colorectal cancer with 5-ASA inhibited mTOR signalling in vitro and in vivo. 5-ASA had no effect on any of the pathways that regulate the activity of the tuberous sclerosis complex in colorectal cancer cells. Both proliferation and mTOR activity depended on PLD, an enzyme that generates phosphatidic acid (PA). 5-ASA treatment inhibited PLD activity and proliferation; these effects could be rescued with exogenous PA.

CONCLUSION

5-ASA interferes with proliferation of colorectal cancer cells via inhibition of PLD-dependent generation of PA and loss of mTOR signalling.