Interleukin-21 in cancer immunotherapy: Friend or foe?

Interleukin (IL)-21, a cytokine produced by activated conventional CD4+ T lymphocytes and Natural Killer T cells, drives anti-tumor immunity in the skin and kidney. However IL-21 is also pro-inflammatory in many tissues and promotes colitis-associated colon cancer. Understanding the biology of IL-21 in these different situations is needed to ensure maximal therapeutic benefit.

Real-time Interobserver Agreement in Bowel Ultrasonography for Diagnostic Assessment in Patients With Crohn's Disease: An International Multicenter Study

BACKGROUND

The unavailability of standardized parameters in bowel ultrasonography (US) commonly used in Crohn's disease (CD) and the shortage of skilled ultrasonographers are 2 limiting factors in the use of this imaging modality around the world. The aim of this study is to evaluate interobserver agreement among experienced sonographers in the evaluation of bowel US parameters in order to improve standardization in imaging reporting and interpretation.

METHODS

Fifteen patients with an established diagnosis of CD underwent blinded bowel US performed by 6 experienced sonographers. Prior to the evaluation, the sonographers and clinical and radiological IBD experts met to formally define the US parameters. Interobserver agreement was tested with the Quatto method (s).

RESULTS

All operators agreed on the presence/absence of CD lesions and distinguished absence of/mild activity or moderate/severe lesions in all patients. S values were moderate for bowel wall thickness (s = 0.48, P = n.s.), bowel wall pattern (s = 0.41, P = n.s.), vascularization (s = 0.52, P = n.s.), and presence of lymphnodes (s = 0.61, P = n.s.). Agreement was substantial for lesion location (s = 0.68, P = n.s.), fistula (s = 0.74, P = n.s.), phlegmon (s = 0.78, P = 0.04), and was almost perfect for abscess (s = 0.95, P = 0.02). Poor agreement was observed for mesenteric adipose tissue alteration, lesion extent, stenosis, and prestenotic dilation.

CONCLUSIONS

In this study, the majority of the US parameters used in CD showed moderate/substantial agreement. The development of shared US imaging interpretation patterns among sonographers will lead to improved comparability of US results among centers and facilitate the development of multicenter studies and the spread of bowel US training, thereby allowing a wider adoption of this useful technique.

Development of an index to define overall disease severity in IBD

BACKGROUND AND AIM

Disease activity for Crohn's disease (CD) and UC is typically defined based on symptoms at a moment in time, and ignores the long-term burden of disease. The aims of this study were to select the attributes determining overall disease severity, to rank the importance of and to score these individual attributes for both CD and UC.

METHODS

Using a modified Delphi panel, 14 members of the International Organization for the Study of Inflammatory Bowel Diseases (IOIBD) selected the most important attributes related to IBD. Eighteen IOIBD members then completed a statistical exercise (conjoint analysis) to create a relative ranking of these attributes. Adjusted utilities were developed by creating proportions for each level within an attribute.

RESULTS

For CD, 15.8% of overall disease severity was attributed to the presence of mucosal lesions, 10.9% to history of a fistula, 9.7% to history of abscess and 7.4% to history of intestinal resection. For UC, 18.1% of overall disease severity was attributed to mucosal lesions, followed by 14.0% for impact on daily activities, 11.2% C reactive protein and 10.1% for prior experience with biologics. Overall disease severity indices were created on a 100-point scale by applying each attribute's average importance to the adjusted utilities.

CONCLUSIONS

Based on specialist opinion, overall CD severity was associated more with intestinal damage, in contrast to overall UC disease severity, which was more dependent on symptoms and impact on daily life. Once validated, disease severity indices may provide a useful tool for consistent assessment of overall disease severity in patients with IBD.

Nutritional status and bioelectrical phase angle assessment in adult Crohn disease patients receiving anti-TNFα therapy

BACKGROUND

Altered body composition is frequently observed in Crohn's disease (CD) patients.

AIMS

To investigate the nutritional status, and the effect of different therapeutic regimes in adult CD patients.

METHODS

Fat free mass (FFM) and BIA-derived phase angle (PhA) were assessed in 45 CD patients, 22 on conventional therapy (CT) and 23 on maintenance therapy with infliximab (MT). Nutritional status was also assessed in 12 CD patients before and following the induction protocol with infliximab. BIA data of CD patients were compared with those of 20 healthy asymptomatic volunteers. In CD patients C Reactive Protein (CRP) and albuminaemia dosage were obtained.

RESULTS

The mean values of PhA and of FFM were significantly lower in CT patients when compared with control group and MT patients. Following infliximab treatment FFM increased, although not significantly, while mean phase angle value significantly increased from 4.6±0.3 to 6.2±0.4 (p<0.05). CRP was significantly lower in MT patients compared to that in CT patients.

CONCLUSION

CD patients on conventional therapy showed a lower FFM and a lower mean phase angle score compared to those on infliximab therapy. Following infliximab treatment the mean phase angle score normalized. PhA is a reliable nutritional indicator in IBD patients and could be considered as an additional tool for assessing response to treatment.

CCL20 Is Negatively Regulated by TGF-β1 in Intestinal Epithelial Cells and Reduced in Crohn's Disease Patients With a Successful Response to Mongersen, a Smad7 Antisense Oligonucleotide

BACKGROUND AND AIMS

The chemokine CCL20 is over-produced in epithelium of Crohn's disease [CD] patients and contributes to recruiting immune cells to inflamed gut. Tumour necrosis factor-α [TNF-α] is a powerful inducer of CCL20 in intestinal epithelial cells. In CD, high levels of Smad7 block the activity of transforming growth factor-β1 [TGF-β1], a negative regulator of TNF signalling. We investigated whether intestinal epithelial cell-derived CCL20 is negatively regulated by TGF-β1 and whether Smad7 knock-down reduces CCL20 in CD.

METHODS

CCL20 was evaluated in NCM460, a normal colonic epithelial cell line, stimulated with TGF-β1 and TNF-α, and in Smad7 over-expressing NCM460 cells. CCL20 and Smad7 expression were assessed in sections of CD intestinal specimens by immunochemistry, and in CD colonic explants treated with mongersen, a Smad7 antisense oligonucleotide. CCL20 was examined in serum samples taken from 95 of 166 active CD patients receiving mongersen or placebo for 2 weeks and participating in a phase II, multicentre, double-blind, placebo-controlled study.

RESULTS

CCL20 expression was increased by TNF-α, and this effect was inhibited by TGF-β1 in NCM460 cells, but not in Smad7 over-expressing NCM460 cells. In CD, epithelium CCL20 and Smad7 co-localised, and treatment of CD explants with mongersen reduced CCL20 production. During follow-up, in responders to mongersen, serum CCL20 levels significantly decreased, whereas patients without response/remission to mongersen and placebo patients did not have change in CCL20.

CONCLUSIONS

TGF-β1 reduces intestinal epithelial cell-derived CCL20 production, an effect abrogated by Smad7. CD patients responding to mongersen demonstrated a reduction in serum CCL20.

High Smad7 sustains inflammatory cytokine response in refractory coeliac disease

Refractory coeliac disease (RCD) is a form of coeliac disease (CD) resistant to gluten-free diet and associated with elevated risk of complications. Many effector cytokines over-produced in the gut of patients with RCD are supposed to amplify the tissue-destructive immune response, but it remains unclear if the RCD-associated mucosal inflammation is sustained by defects in counter-regulatory mechanisms. The aim of the present study was to determine whether RCD-related inflammation is marked by high Smad7, an intracellular inhibitor of transforming growth factor-β₁ (TGF-β₁ ) activity. Smad7 was evaluated in duodenal biopsy samples of patients with RCD, patients with active CD, patients with inactive CD and healthy controls by Western blotting, immunohistochemistry and real-time PCR. In the same samples, TGF-β₁ and phosphorylated (p)-Smad2/3 were evaluated by ELISA and immunohistochemistry, respectively. Pro-inflammatory cytokine expression was evaluated in RCD samples cultured with Smad7 sense or antisense oligonucleotide. Smad7 protein, but not RNA, expression was increased in RCD compared with active and inactive CD patients and healthy controls and this was associated with defective TGF-β₁ signalling, as marked by diminished p-Smad2/3 expression. TGF-β₁ protein content did not differ among groups. Knockdown of Smad7 in RCD biopsy samples reduced interleukin-6 and tumour necrosis factor-α expression. In conclusion, in RCD, high Smad7 associates with defective TGF-β₁ signalling and sustains inflammatory cytokine production. These results indicate a novel mechanism by which the mucosal cytokine response is amplified in RCD and suggest that targeting Smad7 can be therapeutically useful in RCD.

Inflammatory Bowel Disease Phenotype as Risk Factor for Cancer in a Prospective Multicentre Nested Case-Control IG-IBD Study

BACKGROUND AND AIMS

Cancer risk in inflammatory bowel disease [IBD] is still debated. In a prospective, multicentre, nested case-control study, we aimed to characterise incident cases of cancer in IBD. The role of immunomodulators vs clinical characteristics of IBD as risk factors for cancer was also investigated.

MATERIALS AND METHODS

From January 2012 to December 2014, each IBD patient with incident cancer was matched with two IBD patients without cancer for: IBD type, gender, and age. Risk factors were assessed by multivariate regression analysis.

RESULTS

IBD patients considered numbered 44619: 21953 Crohn's disease [CD], 22666 ulcerative colitis [UC]. Cancer occurred in 174 patients: 99 CD [CD-K], 75 UC [UC-K]. Controls included 198 CD [CD-C], 150 UC [UC-C]. Cancer incidence in IBD was 3.9/1000, higher in CD (4.5/1000 [99/21,953]) than in UC (3.3/1000 [75/22,666]; p = 0.042). Cancers involved: digestive system [36.8%], skin [13.2%], urinary tract [12.1%], lung [8.6%], breast [8%], genital tract [6.9%], thyroid [4.6%], lymphoma [3.5%], others [6.3%]. In CD, penetrating behaviour and combined thiopurines and tumour necrosis factor alpha [TNFα] antagonists were risk factors for cancer overall: odds ratio [OR] (95% confidence interval [CI] 2.33 [1.01-5.47]); 1.97 [1.1-3.5]; and for extracolonic cancers 3.9 [1.56-10.1]; 2.15 [1.17-4.1], respectively. In UC, risk factors were pancolitis and disease-related surgery for cancer overall (OR: 2.52 [1.26-5.1]; 5.09 [1.73-17.1]); disease-related surgery for colorectal cancer [CRC] (OR 3.6 [1.0-12]); and extensive and left-sided vs distal UC for extracolonic cancers (OR: 2.55 [1.15-5.9]; 2.6 [1.04-6.6]), respectively.

CONCLUSIONS

In a multicentre study, penetrating CD and extensive UC were risk factors for cancer overall. Cancer incidence was higher in CD than in UC.

[IBD: Crohn's disease]

Crohn's disease (CD) is a chronic inflammatory disorder that primarily affects small intestine and colon and causes tissue damage. The aetiology of CD is unknown, but a large body of evidence suggests that the pathological process is driven by excessive immune response, which is direct against components of the luminal flora and sustained by defects in counter-regulatory mechanisms. CD is a transmural progressive and destructive disease leading to irreversible bowel damage characterized by stenosis of the intestinal lumen and penetrating lesions such as fistulas and abscesses. The goals of medical therapy in CD are to: 1) induce symptomatic remission; 2) maintain steroid-free remission; 3) enhance quality of life; 4) prevent/treat complications of disease; 5) avoid short and long term toxicity of therapy. Achieving these goals requires a sophisticated approach that tailors therapy to each patient, involving attempts to risk stratify the patient, optimizing each therapy, and monitoring for objective evidence of resolution of inflammation. Although the number of medications available to treat CD has increased in the last 15 years, with the important addition of biologic therapies, including anti-TNF antibodies such as infliximab, adalimumab, and certolizumab pegol, and more recently, vedolizumab, an anti-α4β7 integrin antibody, the number of agents remains relatively small.

Celiac Disease-Related Inflammation Is Marked by Reduction of Nkp44/Nkp46-Double Positive Natural Killer Cells

INTRODUCTION AND AIM

Natural killer (NK) cells are a first line of defence against viruses and down-regulation of NK cell cytotoxic receptors represents one of the strategies by which viruses escape the host's immune system. Since onset of celiac disease (CD), a gluten-driven enteropathy, has been associated with viral infections, we examined whether CD-associated inflammation is characterized by abnormal distribution of NK cell receptors involved in recognition of viral-infected cells.

MATERIALS AND METHODS

Intraepithelial mononuclear cells, isolated from duodenal biopsies of active and inactive CD patients and healthy controls (CTR) and jejunal specimens of obese subjects undergoing gastro-intestinal bypass, were analysed for NK cell markers by flow-cytometry. Expression of granzyme B, interleukin (IL)-22 and tumor necrosis factor (TNF)-α was as assessed in freshly isolated and toll-like receptor (TLR) ligand-stimulated cells.

RESULTS

The percentages of total NK cells and NKT cells did not significantly differ between CD patients and CTR. In active CD, the fractions of NKp30+ NK cells, NKG2D+ NK cells and NKG2D+ NKT cells were significantly increased as compared to inactive CD patients and CTR. In contrast, CD-associated inflammation was marked by diminished presence of NKG2A+ NK cells and NKG2A+ NKT cells. The fractions of NK cells and NKT cells expressing either NKp44 or NKp46 did not differ between CD and controls, but in CD less NK cells and NKT cells co-expressed these receptors. NKp44/NKp46-double positive cells produced granzyme B and IL-22 but not TNF-α and responded to TLR ligands with enhanced expression of granzyme B.

CONCLUSIONS

These data indicate that active phase of CD associates with reduced presence of NKp44/NKp46-double positive NK cells and NKT cells in the epithelial compartment.

Interleukin-21 sustains inflammatory signals that contribute to sporadic colon tumorigenesis

Interleukin (IL)-21 triggers inflammatory signals that contribute to the growth of neoplastic cells in mouse models of colitis-associated colorectal cancer (CRC). Because most CRCs are sporadic and arise in the absence of overt inflammation we have investigated the role of IL-21 in these tumors in mouse and man. IL-21 was highly expressed in human sporadic CRC and produced mostly by IFN-γ-expressing T-bet/RORγt double-positive CD3+CD8− cells. Stimulation of human CRC cell lines with IL-21 did not directly activate the oncogenic transcription factors STAT3 and NF-kB and did not affect CRC cell proliferation and survival. In contrast, IL-21 modulated the production of protumorigenic factors by human tumor infiltrating T cells. IL-21 was upregulated in the neoplastic areas, as compared with non-tumor mucosa, of Apc^min/+ mice, and genetic ablation of IL-21 in such mice resulted in a marked decrease of both tumor incidence and size. IL-21 deficiency was associated with reduced STAT3/NF-kB activation in both immune cells and neoplastic cells, diminished synthesis of protumorigenic cytokines (that is, IL-17A, IL-22, TNF-α and IL-6), downregulation of COX-2/PGE2 pathway and decreased angiogenesis in the lesions of Apc^min/+ mice. Altogether, data suggest that IL-21 promotes a protumorigenic inflammatory circuit that ultimately sustains the development of sporadic CRC.

Impact of patient characteristics on the clinical efficacy of mongersen (GED-0301), an oral Smad7 antisense oligonucleotide, in active Crohn's disease

BACKGROUND

In a phase 2 study, mongersen, an oral antisense oligonucleotide targeting Smad7, was effective in inducing clinical remission in approximately 60% of patients with active Crohn's disease (CD).

AIM

In a post hoc analysis to evaluate those patient disease characteristics that may have influenced the efficacy and safety of mongersen therapy.

METHODS

Patients with steroid-dependent/resistant, active CD were randomised to mongersen 10, 40 or 160 mg/day or placebo for 2 weeks; patients were followed for 10 weeks. Clinical remission [Crohn's Disease Activity Index (CDAI) score <150] and clinical response (CDAI score reduction ≥100 points) were assessed at weeks 2, 4 and 12 for these subgroups: disease duration <5/≥5 years, human serum C-reactive protein (hsCRP) <3/≥3 mg/L, and CDAI at baseline ≤260/>260. Additional patient baseline and disease characteristics were explored.

RESULTS

Clinical remission and response rates were significantly higher in patients receiving mongersen 40 and 160 mg/day but not 10 mg/day vs. placebo and independent of disease duration and hsCRP. Patients with baseline CDAI ≤260 had significantly higher remission rates with 40 and 160 mg/day. In patients with baseline CDAI >260, remission rates were statistically greater with 160 mg/day and numerically better with 40 mg/day vs. placebo. Adverse event rates were similar across treatment groups. Mongersen was safe and well tolerated.

CONCLUSIONS

Patients with higher CDAI scores achieved clinical remission most frequently with the highest mongersen dose. Disease duration and baseline human serum C-reactive protein did not appear to significantly impact efficacy of mongersen in this study (EudraCT Number: 2011-002640-27.).

Aryl hydrocarbon receptor-driven signals inhibit collagen synthesis in the gut

Fibrostrictures (FS) are a major complication of Crohn's disease (CD). Pathogenesis of FS is not fully understood, but activation of fibroblasts and excessive collagen deposition are crucial in the development of FS. Here, we investigated the role of aryl hydrocarbon receptor (AhR) in intestinal fibrosis. AhR RNA and protein expression were evaluated in intestinal fibroblasts of CD patients and controls. CD fibroblasts were stimulated with TGF-β1 or TNF-α in the presence or absence of the AhR activator Ficz, an AhR antagonist CH223191, or a specific AhR-silencing RNA. In CD fibroblasts, TGF-β1 and TNF-α increased Col1A1, Col3A1 and α-SMA transcripts and collagen secretion and this effect was reduced by Ficz and upregulated by CH22319. TGF-β1 or TNF-α induced activation of p38 and ERK1/2 MAP kinases was decreased by Ficz and increased by CH223191. The inhibitory effect of Ficz on Map kinase activation and collagen induction was abolished by AhR silencing. To assess the role of AhR in vivo, mice with trinitrobenzene-sulfonic-acid induced colonic fibrosis were given Ficz or CH223191. Mice given either Ficz or CH223191 produced less or more collagen respectively as compared with control mice. Our results indicate that AhR is a negative regulator of profibrotic signals in the gut.

Antisense approach to inflammatory bowel disease: prospects and challenges

Despite the great success of anti-tumour necrosis factor-based therapies, the treatment of Crohn's disease (CD) and ulcerative colitis (UC) still remains a challenge for clinicians, as these drugs are not effective in all patients, their efficacy may wane with time, and their use can increase the risk of adverse events and be associated with the development of new immune-mediated diseases. Therefore, new therapeutic targets are currently being investigated both in pre-clinical studies and in clinical trials. Among the technologies used to build new therapeutic compounds, the antisense oligonucleotide (ASO) approach is slowly gaining space in the field of inflammatory bowel diseases (IBDs), and three ASOs have been investigated in clinical trials. Systemic administration of alicaforsen targeting intercellular adhesion molecule-1, a protein involved in the recruitment of leukocytes to inflamed intestine, was not effective in CD, even though the same compound was of benefit when given as an enema to UC patients. DIMS0150, targeting nuclear factor (NF) κB-p65, a transcription factor that promotes pro-inflammatory responses, was very promising in pre-clinical studies and is currently being tested in clinical trials. Oral mongersen, targeting Smad7, an intracellular protein that inhibits transforming growth factor (TGF)-β1 activity, was safe and well tolerated by CD patients, and the results of a phase II clinical trial showed the efficacy of the drug in inducing clinical remission in patients with active disease. In this leading article, we review the rationale and the clinical data available regarding these three agents, and we discuss the challenge of using ASOs in IBD.

Interleukin-34 Induces Cc-chemokine Ligand 20 in Gut Epithelial Cells

BACKGROUND AND AIM

Production of chemokines by intestinal epithelial cells is a key step in the amplification of the destructive immune-inflammatory response in patients with inflammatory bowel diseases [IBD]. In this study, we examined whether intestinal epithelial cells express macrophage colony-stimulating factor receptor 1 [M-CSFR-1], the functional receptor of interleukin-34 [IL-34], a cytokine that is over-produced in IBD and supposed to sustain inflammatory pathways.

METHODS

M-CSFR-1 expression was evaluated in intestinal samples of IBD patients, controls, and colon epithelial cell lines by real-time polymerase chain reaction [PCR], immunohistochemistry, and western blotting. DLD-1 cells were stimulated with IL-34 in the presence or absence of MAP kinase inhibitors, chemokine induction was assessed by real-time PCR and enzyme-linked immunosorbent assay [ELISA], and mitogen-activated protein (MAP) kinase activation was monitored by western blotting. The effect of a neutralising IL-34 antibody on CC chemokine ligand (CCL) 20 synthesis was tested in ex vivo organ cultures of IBD mucosal explants.

RESULTS

Enhanced expression of M-CSFR-1 RNA transcripts was seen in inflamed mucosa of IBD patients as compared with controls. Immunohistochemical analysis confirmed up-regulation of M-CSFR-1 in IBD and showed that both epithelial and lamina propria mononuclear cells expressed this receptor. Stimulation of DLD-1 with IL-34 increased CCL20 production through an ERK1/2-dependent mechanism. Consistently, treatment of IBD explants with anti-IL-34 reduced CCL20 production.

CONCLUSIONS

These data show that intestinal epithelial cells are a target of IL-34 and suggest that this cytokine contributes to mediating the cross-talk between epithelial cells and immune cells in IBD.

Impact of a multidisciplinary approach in enteropathic spondyloarthritis patients

Spondyloarthritis (SpA) and inflammatory bowel disease (IBD) are chronic autoinflammatory diseases that partially share the genetic predisposition and the unchecked inflammatory response linking the gut to the joints. The coexistence of both conditions in patients and the increased cross-risk ratios between SpA and IBD strongly suggest a shared pathophysiology. The prevalence of Enteropathic-related Spondyloarthritis (ESpA) in IBD patients shows a wide variation and may be underestimated. It is well accepted that the management of joint pain requires rheumatological expertise in conjunction with gastroenterologist assessment. In this view, we aimed at assessing, in a prospective study performed in a combined Gastro-Intestinal and Rheumatologic "GI-Rhe" clinic: (1) the prevalence of ESpA and other rheumatologic diseases in IBD patients with joint pain; (2) the features of the ESpA population; and (3) the diagnostic delay and the potential impact of the combined assessment. From November 2012 to December 2014, IBD patients with joint pain referring to a dedicated rheumatologist by the IBD-dedicated gastroenterologist were enrolled. Clinical and biochemical evaluations, joint involvement and disease activity assessment, diagnostic delay, and treatment were recorded. IBD patients (n=269) with joint pain were jointly assessed in the "GI-Rhe" Unit. A diagnosis of ESpA was made in 50.5% of IBD patients with joint pain. ESpA patients showed a peripheral involvement in 53% of cases, axial in 20.6% and peripheral and axial in 26.4% of cases. ESpA patients had a higher prevalence of other autoimmune extra-intestinal manifestations and received more anti-TNF treatment compared with IBD patients. A mean diagnostic delay of 5.2 years was revealed in ESpA patients. Patients with joint disease onset in the 2002-2012 decade had reduced diagnostic delay compared with those with onset in the 1980-1990 and 1991-2001 decades. Diagnostic delay was further reduced for patients with joint onset in the last two years in conjunction with the establishment of the GI-Rhe clinic. Multidisciplinary approach improved management of rheumatic disorders in IBD patients allowing a more comprehensive care.

The IL-12/23/STAT Axis as a Therapeutic Target in Inflammatory Bowel Disease: Mechanisms and Evidence in Man

BACKGROUND

In inflamed tissues of patients with inflammatory bowel disease (IBD), many immune and non-immune cells produce a vast array of cytokines, which contribute to expand and maintain the pathologic process. Key Message: Interleukin (IL)-12 and IL-23, 2 heterodimeric cytokines sharing the common p40 subunit, are over-produced in IBD and supposed to play a major role in promoting and/or sustaining the pro-inflammatory cytokine response in these disorders. IL-12 targets mostly T cells and innate lymphoid cells and through activation of Stat4 promotes T helper (Th)1 cell polarization, interferon-x03B3; and IL-21 production, while IL-23 activates Stat3 thus amplifying Th17 cell programs. These observations together with the demonstration that IL-12 and IL-23 drive pathogenic responses in animal models of colitis have paved the way for the development of IL-12p40 blockers. Two monoclonal antibodies (ustekinumab and briakinumab) targeting p40 have been tested in Crohn's disease (CD) patients. Blockade of IL-12p40 is beneficial in CD patients resistant to tumor necrosis factor (TNF) antagonists and promotes resolution of psoriatic lesions that develop in IBD patients following anti-TNF therapy.

CONCLUSIONS

The available human data support the pathogenic role of IL-12/IL-23 in IBD and suggest that IL-12p40 blockers could help manage some subsets of IBD patients.

Psoriasis Phenotype in Inflammatory Bowel Disease: A Case-Control Prospective Study

BACKGROUND AND AIMS

Whether inflammatory bowel disease [IBD] is associated with specific psoriasis phenotypes is undefined. In a case-control prospective study, we aimed to assess the severity and phenotype of psoriasis in IBD vs matched non-IBD controls with psoriasis [non-IBD].

METHODS

From 2011 to 2013, dermatological assessment was performed in all IBD patients showing lesions requiring characterisation. In patients with psoriasis, assessment included: presence, characteristics, and severity. Each IBD patient with psoriasis was matched [gender, ethnicity, age ± 5 years] with one non-IBD patient with psoriasis.

STATISTICAL ANALYSIS

data were expressed as median [range], chi-square, Student's t test.

RESULTS

Dermatological assessment was performed in 251 IBD patients [115 females, age 47 [16-85]; IBD duration 9 years [1-46]]: 158 Crohn's disease [CD] [63%], 93 ulcerative colitis [UC] [37%]. Psoriasis was detected in 62 [25%] IBD patients: 36 [58%] CD, 26 UC [42%; p = 0.44]. Clinical characteristics were comparable between IBD patients with or without psoriasis: age 50 [23-72] vs 47 [16-85]; IBD duration 9.5 [1-46] vs 9 [1-41]; p = non-significant]. The non-IBD group included 62 patients with psoriasis: 35 male; age 47 [18-75]. Mild psoriasis was more frequent in IBD vs non-IBD [87% vs 53%; p < 0.0001], whereas moderate and severe psoriasis were more frequent in non-IBD vs IBD [37% vs 13%, p = 0.004; 10% vs 0%; p = 0.036]. Plaque-type psoriasis was the most common phenotype in both IBD and non-IBD [p < 0.0001 vs others phenotypes].The frequency of plaque-type, nail psoriasis and psoriatic arthritis was lower in IBD vs non-IBD [p = 0.008; p < 0.0001; p = 0.006]. Psoriasis occurred after anti-tumour necrosis factor [TNF]α treatment in six CD patients [7%].

CONCLUSIONS

Severity and phenotypes of psoriasis may differ between patients with IBD and their matched non-IBD controls.

Familial colorectal cancer screening: When and what to do?

Colorectal cancer (CRC) is the third leading cause of death worldwide and represents a clinical challenge. Family members of patients affected by CRC have an increased risk of CRC development. In these individuals, screening is strongly recommended and should be started earlier than in the population with average risk, in order to detect neoplastic precursors, such as adenoma, advanced adenoma, and nonpolypoid adenomatous lesions of the colon. Fecal occult blood test (FOBT) is a non invasive, widespread screening method that can reduce CRC-related mortality. Sigmoidoscopy, alone or in addition to FOBT, represents another screening strategy that reduces CRC mortality. Colonoscopy is the best choice for screening high-risk populations, as it allows simultaneous detection and removal of preneoplastic lesions. The choice of test depends on local health policy and varies among countries.

Th17-type cytokines, IL-6 and TNF-α synergistically activate STAT3 and NF-kB to promote colorectal cancer cell growth

Colorectal cancers (CRCs) often show a dense infiltrate of cytokine-producing immune/inflammatory cells. The exact contribution of each immune cell subset and cytokine in the activation of the intracellular pathways sustaining CRC cell growth is not understood. Herein, we isolate tumor-infiltrating leukocytes (TILs) and lamina propria mononuclear cells (LPMCs) from the tumor area and the macroscopically unaffected, adjacent, colonic mucosa of patients who underwent resection for sporadic CRC and show that the culture supernatants of TILs, but not of LPMCs, potently enhance the growth of human CRC cell lines through the activation of the oncogenic transcription factors signal transducer and activator of transcription 3 (STAT3) and nuclear factor-kappa B (NF-kB). Characterization of immune cell complexity of TILs and LPMCs reveals no differences in the percentages of T cells, natural killer T cells, natural killer (NK) cells, macrophages and B cells. However, T cells from TILs show a functional switch compared with those from LPMCs to produce large amounts of T helper type 17 (Th17)-related cytokines (that is, interleukin-17A (IL-17A), IL-17F, IL-21 and IL-22), tumor necrosis factor-α (TNF-α) and IL-6. Individual neutralization of IL-17A, IL-17F, IL-21, IL-22, TNF-α or IL-6 does not change TIL-derived supernatant-driven STAT3 and NF-kB activation, as well as their proproliferative effect in CRC cells. In contrast, simultaneous neutralization of both IL-17A and TNF-α, which abrogates NF-kB signaling, and IL-22 and IL-6, which abrogates STAT3 signaling, reduces the mitogenic effect of supernatants in CRC cells. IL-17A, IL-21, IL-22, TNF-α and IL-6 are also produced in excess in the early colonic lesions in a mouse model of sporadic CRC, associated with enhanced STAT3/NF-kB activation. Mice therapeutically given BP-1-102, an orally bioavailable compound targeting STAT3/NF-kB activation and cross-talk, exhibit reduced colon tumorigenesis and diminished expression of STAT3/NF-kB-activating cytokines in the neoplastic areas. These data suggest that strategies aimed at the cotargeting of STAT3/NF-kB activation and interaction between them might represent an attractive and novel approach to combat CRC.

Low efficacy of levofloxacin-doxycycline-based third-line triple therapy for Helicobacter pylori eradication in Italy

AIM: To evaluate a levofloxacin-doxycycline-based triple therapy with or without a susceptibility culture test in non-responders to Helicobacter pylori (H. pylori) eradication.

METHODS: A total of 142 (99 women, 43 men; mean 53.0 ± 12.7 years) non-responders to more than two H. pylori eradication therapies underwent susceptibility culture tests or were treated with a seven-day triple therapy consisting of esomeprazole, 20 mg b.i.d., levofloxacin, 500 mg b.i.d., and doxycycline, 100 mg b.i.d., randomly associated with (n = 71) or without (n = 71) Lactobacillus casei DG. H. pylori status was checked in all patients at enrollment and at least 8 wk after the end of therapy. Compliance and tolerability of regimens were also assessed.

RESULTS: H. pylori eradication was achieved in < 50% of patients [per prototol (PP) = 49%; intention to treat (ITT) = 46%]. Eradication rate was higher in patients administered probiotics than in those without (PP = 55% vs 43%; ITT = 54% vs 40%). Estimated primary resistance to levofloxacin was 18% and multiple resistance was 31%. Therapy was well tolerated, and side effects were generally mild, with only one patient experiencing severe effects.

CONCLUSION: Third-line levofloxacin-doxycycline triple therapy had a low H. pylori eradication efficacy, though the success and tolerability of this treatment may be enhanced with probiotics.

Positioning Ultrasonography Into Clinical Practice for the Management of Crohn's Disease

Over the past few years, the technical evolution of ultrasound equipment, the use of oral and intravenous contrast agents, and an increase in the expertise of operators have enhanced the role that ultrasonography plays in the assessment of the gastrointestinal tract. For patients with chronic inflammatory conditions, particularly Crohn's disease, it has been suggested that ultrasonography can be used not only for diagnostic purposes but also in disease management. These developments are reviewed in this article.

Deletion of REXO1L1 locus in a patient with malabsorption syndrome, growth retardation, and dysmorphic features: a novel recognizable microdeletion syndrome?

Background

Copy number variations (CNVs) can contribute to genetic variation among individuals and/or have a significant influence in causing diseases. Many studies consider new CNVs’ effects on protein family evolution giving rise to gene duplicates or losses. “Unsuccessful” duplicates that remain in the genome as pseudogenes often exhibit functional roles. So, changes in gene and pseudogene number may contribute to development or act as susceptibility alleles of diseases.

Case presentation

We report a de novo heterozygous 271 Kb microdeletion at 8q21.2 region which includes the family of REXO1L genes and pseudogenes in a young man affected by global development delay, progeroid signs, and gastrointestinal anomalies. Molecular and cellular analysis showed that the REXO1L1 gene hemizygosity in a patient’s fibroblasts induces genetic instability and increased apoptosis after treatment with different DNA damage-induced agents.

Conclusions

The present results support the hypothesis that low copy gene number within REXO1L1 cluster could play a significant role in this complex clinical and cellular phenotype.

Mongersen, an oral SMAD7 antisense oligonucleotide, and Crohn's disease

BACKGROUND

Crohn's disease-related inflammation is characterized by reduced activity of the immunosuppressive cytokine transforming growth factor β1 (TGF-β1) due to high levels of SMAD7, an inhibitor of TGF-β1 signaling. Preclinical studies and a phase 1 study have shown that an oral SMAD7 antisense oligonucleotide, mongersen, targets ileal and colonic SMAD7.

METHODS

In a double-blind, placebo-controlled, phase 2 trial, we evaluated the efficacy of mongersen for the treatment of persons with active Crohn's disease. Patients were randomly assigned to receive 10, 40, or 160 mg of mongersen or placebo per day for 2 weeks. The primary outcomes were clinical remission at day 15, defined as a Crohn's Disease Activity Index (CDAI) score of less than 150, with maintenance of remission for at least 2 weeks, and the safety of mongersen treatment. A secondary outcome was clinical response (defined as a reduction of 100 points or more in the CDAI score) at day 28.

RESULTS

The proportions of patients who reached the primary end point were 55% and 65% for the 40-mg and 160-mg mongersen groups, respectively, as compared with 10% for the placebo group (P<0.001). There was no significant difference in the percentage of participants reaching clinical remission between the 10-mg group (12%) and the placebo group. The rate of clinical response was significantly greater among patients receiving 10 mg (37%), 40 mg (58%), or 160 mg (72%) of mongersen than among those receiving placebo (17%) (P=0.04, P<0.001, and P<0.001, respectively). Most adverse events were related to complications and symptoms of Crohn's disease.

CONCLUSIONS

We found that study participants with Crohn's disease who received mongersen had significantly higher rates of remission and clinical response than those who received placebo. (Funded by Giuliani; EudraCT number, 2011-002640-27.).

Cancer and immunomodulators in inflammatory bowel diseases

The widespread use of thiopurines and anti-tumor necrosis factors (TNFs) in inflammatory bowel disease (IBD) is a rising concern regarding their potential cancer risk. MEDLINE, EMBASE, and the Cochrane Library database were searched for articles regarding immunomodulators anti-TNF agents in IBD, hematologic malignancies, and solid tumors. Current evidences support that thiopurines and anti-TNFs used alone or in combination do not increase the overall cancer risk in IBD. Thiopurines use, with or without anti-TNFs, is associated with an increased risk of lymphoma, particularly non-Hodgkin lymphoma, in Crohn's disease. Combined treatment significantly increases the risk of a rare hepatosplenic T-cell lymphoma, particularly in young male patients with Crohn's disease. An increased risk of nonmelanotic skin cancer is also observed when using thiopurines in IBD, whereas a slightly increased risk of melanoma is observed when using anti-TNFs. The role played by immunomodulators in the development of other cancer types (i.e., urinary) as also by the severity of IBD is under investigation. Although the incidence of specific malignancies (lymphoma, skin cancers) seems to be increased by immunomodulators, their absolute number is low. As thiopurines and anti-TNFs are highly effective in IBD, current evidences support that in appropriate hands, their benefits overwhelm the cancer risk. However, a careful selection of both patients and timing of treatment is mandatory, particularly in young male patients with Crohn's disease. Immunomodulators should therefore be handled by experienced and dedicated gastroenterologists who aware of the potential, although low, cancer risk associated with their use in patients with IBD.

A sonographic lesion index for Crohn's disease helps monitor changes in transmural bowel damage during therapy

BACKGROUND & AIMS

Therapeutic antibodies against tumor necrosis factor α (anti-TNF) are effective in patients with Crohn's disease (CD). Mucosal healing is a surrogate marker of efficacy, but little is known about the effects of anti-TNF agents on structural damage in the intestine. Small-intestine contrast ultrasonography (SICUS) is a valuable tool for assessing CD lesions. A new sonographic quantitative index (the sonographic lesion index for CD [SLIC]) was developed to quantify changes in CD lesions detected by SICUS. We explored whether the SLIC can be used to monitor transmural bowel damage in CD patients during anti-TNF therapy.

METHODS

We performed a prospective study of 29 patients with ileal or ileocolonic CD treated with anti-TNF agents; patients underwent SICUS before and after scheduled induction and maintenance therapy. To determine whether changes that can be detected by SICUS occur independently of anti-TNF therapy, 7 patients with ileal CD treated with mesalamine were enrolled as controls. A clinical response was defined as steroid-free remission, with CD activity index scores less than 150.

RESULTS

We observed significant improvements in SLIC scores and subscores after induction and maintenance therapy with anti-TNFs, compared with before therapy. SLIC scores and subscores and index classes were improved significantly in patients with vs without clinical responses. Controls had no improvements in terms of CD activity index or SLIC scores, or index classes.

CONCLUSIONS

Sonographic assessment using the quantitative index SLIC can be used to monitor changes in transmural bowel damage during anti-TNF therapy for CD.

Defective expression of SIRT1 contributes to sustain inflammatory pathways in the gut

In inflammatory bowel disease (IBD), tissue damage is driven by an excessive immune response, poorly controlled by counter-regulatory mechanisms. SIRT1, a class III NAD+-dependent deacetylase, regulates negatively the expression of various proteins involved in the control of immune-inflammatory pathways, such as Stat3, Smad7, and NF-κB. Here we examined the expression, regulation, and function of SIRT1 in IBD. SIRT1 RNA and protein expression was less pronounced in whole biopsies and lamina propria mononuclear cells (LPMCs) of IBD patients in comparison with normal controls. SIRT1 expression was downregulated in control LPMC by tumor necrosis factor (TNF)-α and interleukin (IL)-21, and upregulated in IBD LPMC by neutralizing TNF-α and IL-21antibodies. Consistently, SIRT1 expression was increased in mucosal samples taken from IBD patients successfully treated with Infliximab. Treatment of IBD LPMC with Cay10591, a specific SIRT1 activator, reduced NF-κB activation and inhibited inflammatory cytokine synthesis, whereas Ex527, an inhibitor of SIRT1, increased interferon (IFN)-γ in control LPMC. SIRT1 was also reduced in mice with colitis induced by 2,4,6-trinitrobenzenesulphonic acid or oxazolone. Cay10591 prevented and cured experimental colitis whereas Ex527 exacerbated disease by modulating T cell-derived cytokine response. Data indicate that SIRT1 is downregulated in IBD patients and colitic mice and suggest that SIRT1 activation can help attenuate inflammatory signals in the gut.

Serum regenerating islet-derived 3-alpha is a biomarker of mucosal enteropathies

BACKGROUND

The clinical presentation of organic and functional intestinal disorders can overlap and clinicians often rely on invasive and time-consuming procedures to make a final diagnosis. Regenerating islet-derived 3-alpha (Reg3α) is detectable in the circulation of patients with intestinal graft-versus host disease and patients with inflammatory bowel disease (IBD).

AIM

To determine whether serum Reg3α testing is useful for discriminating mucosal enteropathies from functional intestinal disorders.

METHODS

We prospectively included 47 patients with active coeliac disease (ACD), 13 patients with refractory coeliac disease (RCD), seven patients with common variable immunodeficiency (CVID), 72 patients with active Crohn's disease, 22 patients with active ulcerative colitis (UC) and 28 patients with irritable bowel syndrome (IBS)-related diarrhoea. Sera were also taken from 10 CD patients before and after 6-12 months of a gluten-free diet (GFD) and from 14 patients with IBD before and after induction therapy with Infliximab (IFX). Sera of 119 healthy volunteers were used to determine the cut-off value. Reg3α levels were measured by a commercial ELISA kit.

RESULTS

Levels of Reg3α exceeded the cut-off value of the assay in 43/47(91%) ACD patients, 13/13(100%) RCD patients, 7/7(100%) CVID patients, 65/72(90%) Crohn's disease patients, 17/22(77%) UC patients and one patient with IBS(4%). Reg3α levels distinguished mucosal enteropathies from IBS with a sensitivity of 90% and a specificity of 96%. Reg3α levels significantly decreased in CD patients following a GFD and in IBD patients after treatment with IFX.

CONCLUSION

Reg3α is a serum biomarker of intestinal damage that, combined with clinical data, identifies patients who should undergo invasive tests for diagnosing enteropathies.

Proteinase activated-receptors-associated signaling in the control of gastric cancer

Gastric cancer (GC) is the fourth most common cancer in the world and the second cause of cancer-related death. Gastric carcinogenesis is a multifactorial process, in which environmental and genetic factors interact to activate multiple intracellular signals thus leading to uncontrolled growth and survival of GC cells. One such a pathway is regulated by proteinase activated-receptors (PARs), seven transmembrane-spanning domain G protein-coupled receptors, which comprise four receptors (i.e., PAR-1, PAR-2, PAR-3, and PAR-4) activated by various proteases. Both PAR-1 and PAR-2 are over-expressed on GC cells and their activation triggers and/or amplifies intracellular pathways, which sustain gastric carcinogenesis. There is also evidence that expression of either PAR-1 or PAR-2 correlates with depth of wall invasion and metastatic dissemination and inversely with the overall survival of patients. Consistently, data emerging from experimental models of GC suggest that both these receptors can be important targets for therapeutic interventions in GC patients. In contrast, PAR-4 levels are down-regulated in GC and correlate inversely with the aggressiveness of GC, thus suggesting a negative role of this receptor in the control of GC. In this article we review the available data on the expression and role of PARs in GC and discuss whether manipulation of PAR-driven signals may be useful for interfering with GC cell behavior.

TGF-Beta signaling manipulation as potential therapy for IBD

Crohn's disease (CD) and ulcerative colitis (UC), two chronic and relapsing inflammatory bowel diseases (IBD), are supposed to develop in genetically-predisposed individuals as a result of an excessive immune mucosal response directed against normal components of the gut microbiota. There is also evidence that defects in counter-regulatory mechanisms play a major role in the pathogenesis of IBD. One such a defect involves TGF-β1, a cytokine produced by multiple cells types and able to inhibit pathogenic responses in the gut. In both CD and UC, TGF-β1 is highly produced but unable to signal through the TGF-β receptor-associated Smad pathway and suppress production of inflammatory molecules. Abrogation of TGF-β1 activity has been related to Smad7, an intracellular protein that binds to TGF-β receptor and inhibits TGF-β1-driven Smad-dependent signalling. Indeed, silencing of Smad7 with a specific antisense oligonucleotide restores TGF-β1/Smad signalling, thereby down-regulating inflammatory cytokine production and ameliorating experimental colitis in mice. Altogether these observations led to the development of an oral pharmaceutical compound containing the specific Smad7 antisense oligonucleotide (herein termed GED0301), which seems to be safe and well tolerated in CD patients. In this article we summarize the data supporting the pathogenic role of Smad7 in IBD and discuss the recent results of the use of GED0301 in CD.

Plasma cells in the mucosa of patients with inflammatory bowel disease produce granzyme B and possess cytotoxic activities

In both Crohn's disease (CD) and ulcerative colitis (UC), the gut is massively infiltrated with B cells and plasma cells, but the role of these cell types in the pathogenesis of gut tissue damage remains largely unknown. Human B cells express granzyme B (GrB) when cultured with IL-21, a cytokine overproduced in CD and UC mucosa. We therefore examined whether mucosal B cells express GrB and have cytotoxic activity in inflammatory bowel disease (IBD). GrB-expressing CD19(+) and IgA(+) cells were seen in the normal intestinal mucosa, but they were significantly more frequent in both CD and UC. In contrast, only a minority of CD19(+) and IgA(+) cells expressed perforin with no difference between IBD and controls. GrB-producing CD19(+) cells expressed CD27 and were CD38(high) and CD20 negative. CD19(+) B cells from IBD patients induced HCT-116 cell death. IL-21 enhanced GrB expression in control CD19(+) B cells and increased their cytotoxic activity. These data indicate that IBD-related inflammation is marked by mucosal accumulation of cytotoxic, GrB-expressing CD19(+) and IgA(+) cells, suggesting a role for these cells in IBD-associated epithelial damage.

Sampling of proximal and distal duodenal biopsies in the diagnosis and monitoring of celiac disease

BACKGROUND

Since celiac disease-associated mucosal lesions are patchy, the diagnosis of the disease requires histological evaluation of multiple duodenal biopsies.

AIM

To examine whether adequate biopsy sampling in either the bulb or distal duodenum is sufficient to diagnose celiac disease.

METHODS

Twenty-five patients with positive celiac disease-specific serology and 17 patients with negative serology, who were on a gluten-containing diet, and 13 celiac disease patients on a gluten-free diet were consecutively and prospectively enrolled. Mucosal damage, anti-transglutaminase-2 IgA deposits, interferon-γ, interleukin-17A and interleukin-15 transcripts were evaluated in bulb and distal duodenal biopsies.

RESULTS

All patients with positive celiac disease-specific serology exhibited villous atrophy in both duodenal sites. In this group, mucosal anti-transglutaminase-2 IgA deposits were found in 24/25 (96%) bulb samples and 22/25 (88%) distal duodenal samples. No villous atrophy was documented in patients with negative serology. Interferon-γ and interleukin-17A were over-expressed in both duodenal sites of patients with villous atrophy, unlike patients with normal duodenal morphology (p<0.001). Among treated celiac disease patients, 2 (15.4%) had villous atrophy exclusively in the bulb and 6 (46.2%) had minimal histological abnormalities at both sites.

CONCLUSION

Sampling in the bulb and distal duodenum could be sufficient to diagnose/exclude celiac disease.

A family study of asymptomatic small bowel Crohn's disease

BACKGROUND

Discrepancies between severity of lesions and symptoms may be observed in Crohn's disease. We prospectively assessed whether Crohn's disease may be diagnosed among asymptomatic relatives of patients, using Small Bowel Contrast Ultrasonography.

METHODS

Diagnosis of asymptomatic Crohn's disease relatives was defined ultrasonographically as: bowel wall thickness >3mm, bowel dilation/stricture, lumen diameter >2.5 cm. Diagnosis was confirmed by ileocolonoscopy. Subjects were also screened for the Leu3020insC mutation.

RESULTS

Consent was given by 35 asymptomatic first-degree relatives of 18 Crohn's disease patients. Ultrasonography indicated increased bowel wall thickness (5mm) compatible with ileal Crohn's disease in 1 relative (2.8%), a 42 year-old male. Ileocolonoscopy, histology, and radiology confirmed the diagnosis of stricturing ileal Crohn's disease. Gallbladder stones were detected in 7/35 (20%) relatives and Leu3020insC mutation in 3/35 (8.5%).

CONCLUSIONS

Small Bowel Contrast Ultrasonography may be a useful tool to diagnose asymptomatic small bowel Crohn's disease among first-degree relatives of patients.

A functional role for Smad7 in sustaining colon cancer cell growth and survival

Initially identified as an inhibitor of transforming growth factor (TGF)-β mainly owing to its ability to bind TGF-β receptor type I and abrogate TGF-β-driven signaling, Smad7 can interact with additional intracellular proteins and regulate TGF-β-independent pathways, thus having a key role in the control of neoplastic processes in various organs. Genome-wide association studies have shown that common alleles of Smad7 influence the risk of colorectal cancer (CRC), even though the contribution of Smad7 in colon carcinogenesis is not fully understood. In this study, we assessed the expression and role of Smad7 in human and mouse models of sporadic CRC. We document a significant increase of Smad7 in human CRC relative to the surrounding nontumor tissues and show that silencing of Smad7 inhibits the growth of CRC cell lines both in vitro and in vivo after transplantation into immunodeficient mice. Knockdown of Smad7 results in enhanced phosphorylation of the cyclin-dependent kinase (CDK)2, accumulation of CRC cells in S phase and enhanced cell death. Smad7-deficient CRC cells have lower levels of CDC25A, a phosphatase that dephosphorylates CDK2, and hyperphosphorylated eukaryotic initiation factor 2 (eIF2)α, a negative regulator of CDC25 protein translation. Consistently, knockdown of Smad7 associates with inactivation of eIF2α, lower CDC25A expression and diminished fraction of proliferating cells in human CRC explants, and reduces the number of intestinal tumors in Apc^min/+ mice. Altogether, these data support a role for Smad7 in sustaining colon tumorigenesis.

Smad7 induces plasticity in tumor-infiltrating Th17 cells and enables TNF-alpha-mediated killing of colorectal cancer cells

Transforming growth factor-beta (TGF-β) is deeply involved in colorectal cancer development and the disruption of the TGF-β signaling in dysplastic cells is required for tumor to grow. Nevertheless, tumor cells express TGF-β to escape the immune surveillance mediated by T cells. T-cell expression of Smad7, an intracellular inhibitor of the TGF-β signaling, protects against colitis-associated colorectal cancer. However, whether Smad7 in T cells might influence colorectal cancer growth independently of chronic inflammation and which T-cell subset is involved in this process is unknown. To address this issue, T-cell-specific Smad7 transgenic mice and wild-type (WT) littermates were subcutaneously transplanted with syngenic MC38 colon carcinoma cells. Smad7Tg mice were resistant to tumor development compared with WT mice and protection was dependent on CD4(+) T cells. Smad7 expression in T cells increased the number of tumor-infiltrating Tbet/ROR-γ-t double-positive CD4 T cells characterized by the expression of tumor necrosis factor-alpha (TNF-α) and interferon-gamma but lower IL17A. The low expression of IL17A caused by the Smad7 expression in tumor-infiltrating CD4(+) T cells enabled the TNF-α-mediated killing of cancer cells both in vitro and in vivo, thus indicating that the Smad7-mediated plastic effect on T-cell phenotype induces protection against colorectal cancer.

Impairment of ghrelin synthesis in Helicobacter pylori-colonized stomach: New clues for the pathogenesis of H. pylori-related gastric inflammation

Ghrelin, the ligand of growth hormone secretagogue receptor 1a, takes part in several functions of the digestive system, including regulation of appetite, energy homeostasis, gastric acid secretion and motility. Ghrelin has also immunoregulatory properties and is supposed to inhibit some inflammatory pathways that can mediate gastric damage. Interestingly, ghrelin synthesis is reduced in the gastric mucosa of patients with Helicobacter pylori (H. pylori) infection, a worldwide condition inducing a T helper (Th)1/Th17 cell response-driven gastritis, which may evolve towards gastric atrophy and cancer. In this article, we review the available data on the expression of ghrelin in H. pylori infection and discuss how the defective ghrelin synthesis may contribute to sustain the ongoing inflammatory response in this disease.

The dual role of Smad7 in the control of cancer growth and metastasis

Smad7 was initially identified as an inhibitor of Transforming growth factor (TGF)-β due mainly to its ability to bind TGF-β receptor type I and prevent TGF-β-associated Smad signaling. More recently, it has been demonstrated that Smad7 can interact with other intracellular proteins and regulate also TGF-β-independent signaling pathways thus making a valid contribution to the neoplastic processes in various organs. In particular, data emerging from experimental studies indicate that Smad7 may differently modulate the course of various tumors depending on the context analyzed. These observations, together with the demonstration that Smad7 expression is deregulated in many cancers, suggest that therapeutic interventions around Smad7 can help interfere with the development/progression of human cancers. In this article we review and discuss the available data supporting the role of Smad7 in the modulation of cancer growth and progression.

Appropriate nutrient supplementation in celiac disease

Reduced levels of iron, folate, vitamin B12, vitamin D, zinc, and magnesium are common in untreated celiac disease (CD) patients probably due to loss of brush border proteins and enzymes needed for the absorption of these nutrients. In the majority of patients, removal of gluten from the diet leads to histological recovery and normalization of iron, vitamin, and mineral levels. Iron deficiency anemia is the most common extra-intestinal sign of CD and usually resolves with adherence to a gluten-free diet. However, deficiencies of both folate and vitamin B12 may persist in some patients on a gluten-free diet, thus requiring vitamin supplementation to improve subjective health status. Similarly, exclusion of gluten from the diet does not always normalize bone mineral density; in these cases, supplementation of vitamin D and calcium is recommended. Resolution of mucosal inflammation may not be sufficient to abrogate magnesium deficiency. Since gluten-free cereal products have a lower magnesium content as compared with gluten-containing counterparts, a magnesium-enriched diet should be encouraged in CD patients. In this article we discuss the frequency and clinical relevance of nutrient deficiency in CD and whether and when nutrient supplementation is needed.

Helicobacter pylori infection associates with a mucosal downregulation of ghrelin, negative regulator of Th1-cell responses

BACKGROUND

Helicobacter pylori (Hp)-related gastritis is characterized by a predominant T helper (Th)1/Th17 cell immunity. Ghrelin (GR) has immunoregulatory properties and inhibits experimental Th cell-dependent pathology.

AIMS

To evaluate whether Hp infection associates with changes in GR expression and whether GR negatively regulates Th1/Th17 cytokines during Hp infection.

METHODS

GR expression was evaluated by real-time PCR in gastric biopsies taken from Hp-infected and Hp-uninfected patients and in gastric biopsies of Hp-negative subjects cultured with or without H. pylori culture supernatant. To examine whether GR regulates Hp-induced cytokine production, H. pylori-infected gastric biopsies were stimulated with GR, and interleukin (IL)-12, interferon (IFN)-γ and IL-4 transcripts were evaluated by real-time PCR. IL-12 and IFN-γ were also analyzed in lamina propria mononuclear cells (LPMCs) extracted from Hp-infected gastric biopsies and cultured with GR.

RESULTS

GR RNA transcripts were reduced in biopsies from Hp-infected patients. Treatment of Hp-negative gastric biopsies with Hp culture supernatant reduced GR RNA expression. GR dose-dependently inhibited RNA expression of IL-12 and IFN-γ but not IL-4 in ex vivo cultures of mucosal explants and in cultures of gastric LPMCs from Hp-positive patients.

CONCLUSIONS

GR is downregulated in the gastric mucosa of H. pylori-infected patients. Such a defect could contribute to sustain the ongoing Th1-cell response.

Pyoderma gangrenosum in refractory celiac disease: a case report

BACKGROUND

Pyoderma gangrenosum is an inflammatory neutrophilic dermatosis characterized by painful cutaneous ulcerations and often associated with systemic inflammatory and neoplastic diseases. Here we report the first case of pyoderma gangrenosum in a patient with refractory celiac disease.

CASE PRESENTATION

A 52-year-old woman with a previously diagnosed refractory celiac disease resistant to steroids and immunosuppressive drugs presented to our hospital for a rapidly growing, painful inflammatory skin lesion of the left leg. Physical examination revealed a painful lesion with focal ulceration, necrosis and pus discharge with active inflammatory borders at the external part of the left leg. Histological evaluation of a skin biopsy and analysis of inflammatory cytokines and matrix-degrading proteases in lesional skin samples confirmed the clinical suspicion of pyoderma gangrenosum. Treatment with oral prednisone was rapidly followed by a complete healing of the skin lesion but no improvement of symptoms/signs of malabsorption.

CONCLUSION

Treatment of the patient with systemic steroids healed the skin lesion without improving the underlying refractory celiac disease. This observation raises the possibility that refractory celiac disease and pyoderma gangrenosum may be immunologically different.

Bowel ultrasonography as an aid for diagnosis of intestinal acute graft-versus-host-disease after allogeneic haematopoietic stem cell transplantation

OBJECTIVE

Aim of our prospective study was to investigate accuracy of bowel ultrasonography in detecting gastrointestinal acute graft versus host disease (GVHD), when using clinical assessment as gold standard. In a subgroup of patients, bowel ultrasonography was compared with colonoscopy and histology in diagnosing of gastrointestinal acute GVHD.

METHODS

Fifty-two patients underwent allogeneic hematopoietic stem cell transplantation and developed gastrointestinal symptoms.

RESULTS

Clinical assessment lead to a diagnosis of gastrointestinal acute GVHD in 17/52 patients, no gastrointestinal acute GVHD was detected in 20/52 patients, while 15 patients were not able to complete the study. Bowel ultrasonography detected either bowel wall thickness of the ileum and the colon or dilation in 16/17 patients and showed 94% sensitivity (95% CI 0.69-0.99), 95% specificity (95% CI 0.73-0.99), and 94.5% accuracy. Colonoscopy was performed in 13/52 patients, showing gastrointestinal acute GVHD in 11/13. In these 11 patients, histology confirmed the diagnosis of gastrointestinal acute GVHD, and bowel ultrasonography detected findings compatible with gastrointestinal acute GVHD in all 11 patients, and was negative in the 2 patients with no gastrointestinal acute GVHD.

CONCLUSION

Bowel ultrasonography can be considered a valuable tool to add to clinical assessment for patients with suspected gastrointestinal acute GVHD for addressing a prompt and appropriate treatment.

Role of TH17 cytokines in the control of colorectal cancer

Immune/inflammatory cells infiltrate almost all human solid tumors and affect all stages of carcinogenesis as they produce different cytokine subsets. The overproduction of T_H17 cytokines marks the early stages of colorectal carcinoma (CRC) and negatively influences the prognosis of CRC patients. Studies with murine models of CRC have delineated the mechanisms by which T_H17 cytokines, notably, interleukin (IL)-17A, IL-17F, IL-21, and IL-22, regulate oncogenesis and tumor progression, paving the way to the development of novel anticancer drugs. In this review article, we discuss experimental data supporting the role of T_H17 cytokines in the modulation of colorectal tumorigenesis.

IL-25 prevents and cures fulminant hepatitis in mice through a myeloid-derived suppressor cell-dependent mechanism

Fulminant hepatitis (FH) is a disease characterized by massive destruction of hepatocytes with severe impairment of liver function. The pathogenesis of FH is not fully understood, but hyperactivity of T cells and macrophages with excessive production of cytokines are important hallmarks of the condition. In this study, we investigated the role of interleukin (IL)-25 in FH. IL-25 expression was evaluated in patients with FH and in livers of mice with FH induced by D-galactosamine (D-Gal) and lipopolysaccharide (LPS). Mice were treated with IL-25 before D-Gal/LPS-induced FH and before or after concanavalin A (ConA)-induced FH. Mononuclear cells were isolated from livers of mice treated with or without IL-25 and analyzed for GR1(+) CD11b(+) cells. CFSE-labeled T cells were cocultured with GR1(+) CD11b(+) cells and their proliferation was evaluated by flow cytometry. Mice were also treated with a depleting anti-GR1 antibody before IL-25 and D-Gal/LPS administration. IL-25 was constitutively expressed in mouse and human liver and down-regulated during FH. IL-25 prevented D-Gal/LPS-induced FH and this effect was associated with increased infiltration of the liver with cells coexpressing GR1 and CD11b. In vitro studies showed that GR1(+) CD11b(+) cells isolated from mice given IL-25 inhibited T-cell proliferation. Consistently, in vivo depletion of GR1(+) cells abrogated the protective effect of IL-25 in experimental D-Gal/LPS-induced FH. IL-25 was both preventive and therapeutic in ConA-induced FH.

CONCLUSIONS

IL-25 expression is markedly reduced during human and experimental FH. IL-25 promotes liver accumulation of GR1(+) CD11b(+) cells with immunoregulatory properties.