989 resultados para Inflammatory Signaling
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In this work, the analgesic and anti-inflammatory activities of Zeyheria montana Mart. ethanol leaf extract were investigated at doses of 75, 150 and 300 mg/kg body weight. In the analgesic assay, against a chemical stimulus in mice, acetic acid-induced writhes were significantly inhibited by the extract at doses of 75 mg/kg (67.27%), 150 mg/kg (49.38%) and 300 mg/kg (82.87%). Also, a vigorous decrease in hyperalgesia was observed when measured after 2 h and 6 h of lipopolysaccharide stimulation of rats for all doses of extract tested. Z. montana extract, at doses of 75 and 300 mg/kg, caused very slight central analgesia in rats submitted to thermal stimulus, particularly noticeable at 30 min following treatment. The anti-inflammatory activity of Z. montana extract on carrageenan-induced oedema in rats was evaluated. The oedema development, measured at 180 min following carrageenan intraplantar injection, was significantly reduced by all tested doses: 75 mg/kg (33.30%), 150 mg/kg (45.80%) and 300 mg/kg (75.00%). The LD50 value was greater than 2000 mg/kg. These results demonstrated that the ethanol extract from Z. montana leaf possesses anti-nociceptive and anti-inflammatory activities, which could be of relevance for the pharmacological control of pain and inflammatory processes.
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Background: In spite of the relapsing nature of inflammatory bowel diseases (IBD), on average, 40% of IBD patients are nonadherent to treatments. On the other hand, they are often actively seeking information on their disease. The relationship between information seeking behaviour and adherence to treatment is poorly documented. The main aim of this study was to examine this association among IBD patients. Methods: We used data from the Swiss IBD cohort study. Baseline data included questions on adherence to ongoing treatments. A survey was conducted in October 2009 to assess information sources and themes searched by patients. Crude odds ratio (OR) and 95% CI were calculated for the association between adherence and information seeking. Adjustment for potential confounders and main known risk factors was performed using multivariate logistic regression. Differences in the proportions of information sources and themes were compared between adherent and non-adherent patients. Results: The number of patients eligible was 488. Nineteen percent (N = 99) were non-adherent to treatment and one third (N = 159) were active information seekers. Crude OR for being non-adherent was 69% higher among information seekers compared to non-seekers (OR = 1.69; 95%CI 0.99 2.87). Adjusted OR for non-adherence was OR = 2.39 (95%CI 1.32 4.34) for information seekers compared to non-seekers. Family doctors were 15.2% more often consulted (p = 0.019) among patients who were adherent to treatment compared to those who were not, as were books and TV (+13.1%; p = 0.048). No difference was observed for internet or gastroenterologists as sources of information. Themes of information linked to tips for disease management were 14.2% more often searched among non-adherent patients (p = 0.028) compared to adherent. No difference was observed for the other themes (research and development on IBD, therapies, basic information on the disease, patients' experiences sharing, miscellaneous). Conclusions: Active information seeking was shown to be strongly associated with non-adherence to treatment in a population of IBD patients in Switzerland. Surprisingly themes related to therapies were not especially those on which nonadherent patients focused. Indeed, management of symptoms and everyday life with the disease seemed to be the most pressing information concerns of patients. Results suggest that the family doctor plays an important role in the multidisciplinary care approach needed for IBD patients.
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Leptin, a 16-kDa protein mainly produced by adipose tissue, has been involved in the control of energy balance through its hypothalamic receptor. However, pleiotropic effects of leptin have been identified in reproduction and pregnancy, particularly in placenta, where it was found to be expressed. In the current study, we examined the effect of cAMP in the regulation of leptin expression in trophoblastic cells. We found that dibutyryl cAMP [(Bu)(2)cAMP], a cAMP analog, showed an inducing effect on endogenous leptin expression in BeWo and JEG-3 cell lines when analyzed by Western blot analysis and quantitative RT-PCR. Maximal effect was achieved at 100 microM. Leptin promoter activity was also stimulated, evaluated by transient transfection with a reporter plasmid construction. Similar results were obtained with human term placental explants, thus indicating physiological relevance. Because cAMP usually exerts its actions through activation of protein kinase A (PKA) signaling, this pathway was analyzed. We found that cAMP response element-binding protein (CREB) phosphorylation was significantly increased with (Bu)(2)cAMP treatment. Furthermore, cotransfection with the catalytic subunit of PKA and/or the transcription factor CREB caused a significant stimulation on leptin promoter activity. On the other hand, the cotransfection with a dominant negative mutant of the regulatory subunit of PKA inhibited leptin promoter activity. We determined that cAMP effect could be blocked by pharmacologic inhibition of PKA or adenylyl ciclase in BeWo cells and in human placental explants. Thereafter, we decided to investigate the involvement of the MAPK/ERK signaling pathway in the cAMP effect on leptin induction. We found that 50 microm PD98059, a MAPK kinase inhibitor, partially blocked leptin induction by cAMP, measured both by Western blot analysis and reporter transient transfection assay. Moreover, ERK 1/2 phosphorylation was significantly increased with (Bu)(2)cAMP treatment, and this effect was dose dependent. Finally, we observed that 50 microm PD98059 inhibited cAMP-dependent phosphorylation of CREB in placental explants. In summary, we provide some evidence suggesting that cAMP induces leptin expression in placental cells and that this effect seems to be mediated by a cross talk between PKA and MAPK signaling pathways.
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Background. In cardiopulmonary bypass (CPB) patients, fibrinolysis may enhance postoperative inflammatory response. We aimed to determine whether an additional postoperative dose of antifibrinolytic tranexamic acid (TA) reduced CPB-mediated inflammatory response (IR). Methods. We performed a randomized, double-blind, dose-dependent, parallel-groups study of elective CPB patients receiving TA. Patients were randomly assigned to either the single-dose group (40 mg/Kg TA before CPB and placebo after CPB) or the double-dose group (40 mg/Kg TA before and after CPB). Results. 160 patients were included, 80 in each group. The incident rate of IR was significantly lower in the double-dose-group TA2 (7.5% vs. 18.8% in the single-dose group TA1; P = 0.030). After adjusting for hypertension, total protamine dose and temperature after CPB, TA2 showed a lower risk of IR compared with TA1 [OR: 0.29 (95% CI: 0.10-0.83), (P = 0.013)]. Relative risk for IR was 2.5 for TA1 (95% CI: 1.02 to 6.12). The double-dose group had significantly lower chest tube bleeding at 24 hours [671 (95% CI 549-793 vs. 826 (95% CI 704-949) mL; P = 0.01 corrected-P significant] and lower D-dimer levels at 24 hours [489 (95% CI 437-540) vs. 621(95% CI: 563-679) ng/mL; P = 0.01 corrected-P significant]. TA2 required lower levels of norepinephrine at 24 h [0.06 (95% CI: 0.03-0.09) vs. 0.20(95 CI: 0.05-0.35) after adjusting for dobutamine [F = 6.6; P = 0.014 corrected-P significant]. We found a significant direct relationship between IL-6 and temperature (rho = 0.26; P < 0.01), D-dimer (rho = 0.24; P < 0.01), norepinephrine (rho = 0.33; P < 0.01), troponin I (rho = 0.37; P < 0.01), Creatine-Kinase (rho = 0.37; P < 0.01), Creatine Kinase-MB (rho = 0.33; P < 0.01) and lactic acid (rho = 0.46; P < 0.01) at ICU arrival. Two patients (1.3%) had seizure, 3 patients (1.9%) had stroke, 14 (8.8%) had acute kidney failure, 7 (4.4%) needed dialysis, 3 (1.9%) suffered myocardial infarction and 9 (5.6%) patients died. We found no significant differences between groups regarding these events. Conclusions. Prolonged inhibition of fibrinolysis, using an additional postoperative dose of tranexamic acid reduces inflammatory response and postoperative bleeding (but not transfusion requirements) in CPB patients. A question which remains unanswered is whether the dose used was ideal in terms of safety, but not in terms of effectiveness.
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Blastocystis infection has been reported to be associated with irritable bowel syndrome (IBS), inflammatory bowel disease (IBD) and chronic diarrhoea. The availability of data on the subtypes of Blastocystis found in these patient groups would be of interest in understanding the significance of Blastocystis infection in chronic illness. In this study, we identify Blastocystis subtypes found in patients presenting with IBS, IBD, chronic diarrhoea and asymptomatic patients in Ankara, Turkey. Blastocystis was detected in 11 symptomatic patients by microscopy and 19 by stool culture. Stool culture was more sensitive than microscopy in identifying Blastocystis. Using standard nomenclature adopted in 2007, Blastocystis sp. subtype 3 was the most common in all groups, followed by Blastocystis sp. subtype 2. Identical subtypes of Blastocystis are found in patients with IBS, IBD and chronic diarrhoea. These particular subtypes show low host specificity and are carried by humans and some farm animals. The subtypes of Blastocystis that are commonly found in rodents and certain wild birds were not found in these patients. We suggest a model in which the severity of enteric protozoan infection may be mediated by host factors.
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Background: A functional polymorphism located at 21 from the start codon of the CD40 gene, rs1883832, was previously reported to disrupt a Kozak sequence essential for translation. It has been consistently associated with Graves’ disease risk in populations of different ethnicity and genetic proxies of this variant evaluated in genome-wide association studies have shown evidence of an effect in rheumatoid arthritis and multiple sclerosis (MS) susceptibility. However, the protective allele associated with Graves’ disease or rheumatoid arthritis has shown a risk role in MS, an effect that we aimed to replicate in the present work. We hypothesized that this functional polymorphism might also show an association with other complex autoimmune condition such as inflammatory bowel disease, given the CD40 overexpression previously observed in Crohn’s disease (CD) lesions. Methodology: Genotyping of rs1883832C.T was performed in 1564 MS, 1102 CD and 969 ulcerative colitis (UC) Spanish patients and in 2948 ethnically matched controls by TaqMan chemistry. Principal Findings: The observed effect of the minor allele rs1883832T was replicated in our independent Spanish MS cohort [p= 0.025; OR (95% CI)= 1.12 (1.01–1.23)]. The frequency of the minor allele was also significantly higher in CD patients than in controls [p= 0.002; OR (95% CI)= 1.19 (1.06–1.33)]. This increased predisposition was not detected in UC patients [p= 0.5; OR (95% CI)= 1.04 (0.93–1.17)]. Conclusion: The impact of CD40 rs1883832 on MS and CD risk points to a common signaling shared by these autoimmune conditions
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More than seventy years after their initial characterisation, the aetiology of inflammatory bowel diseases remains elusive. A recent review evaluating the incidence trends of the last 25 years concluded that an increasing incidence has been observed almost worldwide. A north-south gradient is still found in Europe. Genetic associations are variably reproduced worldwide and indicate a strong impact of environmental factors. Tumour necrosis factor alpha (TNF-alpha) has been shown to play a critical role in the pathogenesis of inflammatory bowel disease (IBD). TNF-alpha blockers are biological agents that specifically target this key cytokine in the inflammatory process and have become a mainstay in the therapy of inflammatory bowel diseases. This paper reviews the necessary investigations before using such agents, the use of such agents in pregnancy and lactation, the role of co-immunosuppression, how to monitor efficacy and safety, dose-adaptation, and the decision as to when to switch to another TNF-alpha blocker. Finally it gives recommendations for special situations. Currently there are three TNF-alpha blockers available for clinical use in IBD in Switzerland: infliximab (Remicade), adalimumab (Humira) and certolizumab pegol (Cimzia). Infliximab is a chimeric monoclonal antibody composed of a human IgG1 constant region and a murine variable region and is administered intravenously. Adalimumab is a humanised monoclonal antibody, with both human IgG1 constant and variable regions. Certolizumab pegol is a pegylated, humanised monoclonal anti-TNF fragment antigen binding fragment. Both adalimumab and certolizumab pegol are administered by subcutaneous injection. The efficacy and safety of TNF-alpha blockers in Crohn's disease has been reviewed. The authors conclude that the three above-mentioned agents are effective in luminal Crohn's disease. In fistulizing Crohn's disease, TNF-alpha blockers other than infliximab require additional investigation.
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The ciliary body and iris are pigmented epithelial structures in the anterior eye segment that function to maintain correct intra-ocular pressure and regulate exposure of the internal eye structures to light, respectively. The cellular and molecular factors that mediate the development of the ciliary body and iris from the ocular pigmented epithelium remain to be fully elucidated. Here, we have investigated the role of Notch signaling during the development of the anterior pigmented epithelium by using genetic loss- and gain-of-function approaches. Loss of canonical Notch signaling results in normal iris development but absence of the ciliary body. This causes progressive hypotony and over time leads to phthisis bulbi, a condition characterized by shrinkage of the eye and loss of structure/function. Conversely, Notch gain-of-function results in aniridia and profound ciliary body hyperplasia, which causes ocular hypertension and glaucoma-like disease. Collectively, these data indicate that Notch signaling promotes ciliary body development at the expense of iris formation and reveals novel animal models of human ocular pathologies.
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BACKGROUND The etiology of Ulcerative Colitis (UC) and Crohn's Disease (CD), considered together as Inflammatory Bowel Diseases (IBD), involves environmental and genetic factors. Although some genes are already known, the genetics underlying these diseases is complex and new candidates are continuously emerging. The CD209 gene is located in a region linked previously to IBD and a CD209 functional polymorphism (rs4804803) has been associated to other inflammatory conditions. Our aim was to study the potential involvement of this CD209 variant in IBD susceptibility. METHODS We performed a case-control study with 515 CD patients, 497 UC patients and 731 healthy controls, all of them white Spaniards. Samples were typed for the CD209 single nucleotide polymorphism (SNP) rs4804803 by TaqMan technology. Frequency comparisons were performed using chi2 tests. RESULTS No association between CD209 and UC or CD was observed initially. However, stratification of UC patients by HLA-DR3 status, a strong protective allele, showed that carriage of the CD209_G allele could increase susceptibility in the subgroup of HLA-DR3-positive individuals (p = 0.03 OR = 1.77 95% CI 1.04-3.02, vs. controls). CONCLUSION A functional variant in the CD209 gene, rs4804803, does not seem to be influencing Crohn's disease susceptibility. However, it could be involved in the etiology or pathology of Ulcerative Colitis in HLA-DR3-positive individuals but further studies are necessary.
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The intestinal anti-inflammatory effects of two probiotics isolated from breast milk, Lactobacillus reuteri and L. fermentum, were evaluated and compared in the trinitrobenzenesulfonic acid (TNBS) model of rat colitis. Colitis was induced in rats by intracolonic administration of 10 mg TNBS dissolved in 50% ethanol (0.25 ml). Either L. reuteri or L. fermentum was daily administered orally (5 x 10(8) colony-forming units suspended in 0.5 ml skimmed milk) to each group of rats (n 10) for 3 weeks, starting 2 weeks before colitis induction. Colonic damage was evaluated histologically and biochemically, and the colonic luminal contents were used for bacterial studies and for SCFA production. Both probiotics showed intestinal anti-inflammatory effects in this model of experimental colitis, as evidenced histologically and by a significant reduction of colonic myeloperoxidase activity (P<0.05). L. fermentum significantly counteracted the colonic glutathione depletion induced by the inflammatory process. In addition, both probiotics lowered colonic TNFalpha levels (P<0.01) and inducible NO synthase expression when compared with non-treated rats; however, the decrease in colonic cyclo-oxygenase-2 expression was only achieved with L.fermentum administration. Finally, the two probiotics induced the growth of Lactobacilli species in comparison with control colitic rats, but the production of SCFA in colonic contents was only increased when L. fermentum was given. In conclusion, L. fermentum can exert beneficial immunomodulatory properties in inflammatory bowel disease, being more effective than L. reuteri, a probiotic with reputed efficacy in promoting beneficial effects on human health.
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Capsule endoscopy (CE) offers state-of-the-art imaging of the small bowel. In Crohn's disease its clinical role is still uncertain. This report analyses the usefulness of CE in patients with suspected Cronh's disease, in patients with established Crohn's disease (when assessing severity, occult gastrointestinal bleeding and/or as a guide to therapy), in patients with inflammatory bowel disease unclassified (IBDU), and in individuals with ulcerative colitis. The first item in this group is the most important although there is no strong evidence to establish the position of CE in the diagnostic workup. In patients with established Crohn's disease, recently developed activity scores are promising tools for an accurate assessment of severity. As a guide to therapy, CE should be focused on patients with unexplained symptoms when other investigations are inconclusive. In postoperative Crohn's Disease, international consensus recommended considering CE only if ileocolonoscopy is contraindicated or unsuccessful. In the case of IBDU, studies have shown a significant proportion of patients reclassified with Crohn's disease. In this setting, CE could have a role determining small bowel involvement. The role of CE in ulcerative colitis is limited. Some authors advocate CE before colectomy for refractory cases in order to exclude Crohn's disease. In summary, CE offers a new horizon in inflammatory bowel disease, and a better knowledge of mucosal abnormalities that could offer a paradigm shift: changing from symptom-based disease activity estimation to direct mucosal healing monitoring. Nevertheless, randomized controlled studies are still needed to provide stronger evidence in this setting.
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BACKGROUND Inflammation has been implicated as an etiological factor in several human cancers, including prostate cancer. Allelic variants of the genes involved in inflammatory pathways are logical candidates as genetic determinants of prostate cancer risk. The purpose of this study was to investigate whether single nucleotide polymorphisms of genes that lead to increased levels of pro-inflammatory cytokines and chemokines are associated with an increased prostate cancer risk. METHODS A case-control study design was used to test the association between prostate cancer risk and the polymorphisms TNF-A-308 A/G (rs 1800629), RANTES-403 G/A (rs 2107538), IL1-A-889 C/T (rs 1800587) and MCP-1 2518 G/A (rs 1024611) in 296 patients diagnosed with prostate cancer and in 311 healthy controls from the same area. RESULTS Diagnosis of prostate cancer was significantly associated with TNF-A GA + AA genotype (OR, 1.61; 95% CI, 1.09-2.64) and RANTES GA + AA genotype (OR, 1.44; 95% CI, 1.09-2.38). A alleles in TNF-A and RANTES influenced prostate cancer susceptibility and acted independently of each other in these subjects. No epistatic effect was found for the combination of different polymorphisms studied. Finally, no overall association was found between prostate cancer risk and IL1-A or MCP-1 polymorphisms. CONCLUSION Our results and previously published findings on genes associated with innate immunity support the hypothesis that polymorphisms in proinflammatory genes may be important in prostate cancer development.
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BACKGROUND: Intravitreal neovascular diseases, as in ischemic retinopathies, are a major cause of blindness. Because inflammatory mechanisms influence vitreal neovascularization and cyclooxygenase (COX)-2 promotes tumor angiogenesis, we investigated the role of COX-2 in ischemic proliferative retinopathy. METHODS AND RESULTS: We describe here that COX-2 is induced in retinal astrocytes in human diabetic retinopathy, in the murine and rat model of ischemic proliferative retinopathy in vivo, and in hypoxic astrocytes in vitro. Specific COX-2 but not COX-1 inhibitors prevented intravitreal neovascularization, whereas prostaglandin E2, mainly via its prostaglandin E receptor 3 (EP3), exacerbated neovascularization. COX-2 inhibition induced an upregulation of thrombospondin-1 and its CD36 receptor, consistent with the observed antiangiogenic effects of COX-2 inhibition; EP3 stimulation reversed effects of COX-2 inhibitors on thrombospondin-1 and CD36. CONCLUSIONS: These findings point to an important role for COX-2 in ischemic proliferative retinopathy, as in diabetes.
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Résumé : La voie de signalisation Notch est essentielle pour la différentiation de l'épiderme lors du développement embryonnaire de la peau. Il a été démontré que l'inactivation de Notch1 dans la peau de souris conduit à une hyperplasie de l'épiderme ainsi qu'à la formation subséquente de carcinomes basocellulaires ainsi que de plaques cornéennes. L'inactivation de Notch1 dans la cornée combinée à des lésions mécaniques démontre que les cellules progénitrices de la cornée se différentient en un épithélium hyperplasique et kératinisé comme la peau. Ce changement de destinée cellulaire conduit à une cécité cornéenne et implique des processus non-autonomes aux cellules épithéliales, caractérisés par la sécrétion de FGF-2 par l'épithélium Notch1-/- suivi d'une vascularisation et d'un remaniement du stroma sous-jacent. La déficience en vitamine A est connu comme cause de lésions cornéennes humaines (xérophtalmie sévère). En accord, nous avons trouvé que la signalisation Notch1 était liée au métabolisme de la vitamine A par la régulation de l'expression de CRBP1, nécessaire pour générer un pool de rétinol intracellulaire. La perte de Notch1 dans l'épiderme, l'autre récepteur de la famille présent dans la peau marine, ne conduit pas à un phénotype manifeste. Cependant, l'inactivation dans l'épiderme de Notch1 et Notch2 ensemble, ou de RBP-J, induit une dermatite atopique (DA) sévère chez les souris. De même, les patients souffrants de DA mais pas ceux souffrant de psoriasis ou de lichen plan, ont une réduction marquée de l'expression des récepteurs Notch dans la peau. La perte de Notch dans les keratinocytes conduit à une activation de la voie NF-κB, ce qui ensuite induit la production de TSLP, une cytokine profondément impliquée dans la pathogenèse de la DA. Nous démontrons génétiquement que TSLP est responsable de la DA ainsi que du développent d'un syndrome myéloprolifératif non-autonome aux cellules induit par le G-CSF. Cependant, ces souris avec une inactivation dans l'épiderme de Notch1 et Notch2 et aussi incapables de répondre au TSLP développent des tumeurs invasive sévères caractérisées par une haute activité de signalisation ß-catenin. TSLPR est identifié comme un potentiel suppresseur de tumeur non-autonome aux cellules tumorales; la transplantation de cellules hématopoïétiques TSLPR-/- dans des souris déficientes pour Notch est suffisant pour causer des tumeurs. Summary : The Notch pathway is essential for proper epidermal differentiation during embryonic skin development. It has previously been demonstrated that Notch1 inactivation in marine skin results in epidermal hyperplasia and subsequent formation of basal cell carcinoma-like (BCC-like) tumors as well as corneal plaques. Inducible ablation of Notch1 in the cornea combined with mechanical wounding show that Notch1 deficient corneal progenitor cells differentiate into a hyperplasic, keratinized, skin-like epithelium. This cell fate switch leads to corneal blindness and involves cell non-autonomous processes, characterized by secretion of FGF-2 through Notch1-/- epithelium followed by vascularisation and remodelling of the underlying stroma. Vitamin A deficiency is known to induce a similar corneal defect in humans (severe xerophthalmia). Accordingly, we found that Notch1 signaling is linked to vitamin A metabolism by regulating the expression of CRBP1, required to generate a pool of intracellular retinol. Epidermal loss of Notch2, the other Notch receptor present in marine skin, doesn't lead to any overt phenotypes. However, postnatal epidermis-specific inactivation of both Notch1 and Notch2, or of RBP-J, induces the development of a severe form of atopic dermatitis (AD) in mice. Likewise, patients suffering from AD, but not psoriasis or lichen planas, have a marked reduction of Notch receptor expression in the skin. Loss of Notch in keratinocytes leads to an activation of NF-κB signaling which in turn induces the production of Thymic stromal lymphopoietin (TSLP), a cytokine deeply implicated in the pathogenesis of AD. We genetically demonstrate that TSLP is responsible for AD as well as the development of a cell non-autonomous G-CSF induced myeloproliferative disorder (MPD) in mice. However, these mice with conditional epidermal inactivation of Notch1 and Notch2 as well as incapable to respond to TSLP develop severe invasive tumors characterized by high ß-catenin signaling activity. TSLPR is identified as a potential cell non-autonomous tumor suppressor; transplantation of TSLPR-/- hematopoietic cells into epidermal Notch deficient mice is sufficient to cause tumors.