Differential Diagnosis of Intestinal Tuberculosis from Crohn's Disease and Primary Intestinal Lymphoma in China

Background/Aims:

There are many similarities and overlaps in clinical, radiological, endoscopic, and histological features among intestinal tuberculosis (ITB), Crohn''s disease (CD), and primary intestinal lymphoma (PIL), and the differential diagnosis of ITB can be very challenging for clinicians.

Patients and Methods:

The clinical, radiologic, endoscopic, and pathological data of 213 patients were analyzed retrospectively. According to the diagnostic criteria and exclusive criteria of ITB, CD, and PIL, 83 patients were recruited and divided into three groups, including 30 cases in the ITB group, 38 cases in the CD group, and 15 cases in the PIL group, and the medical data and statistical analysis were recorded.

Results:

Rural patients with abdominal pain as the first symptom and with transverse ulcer and caseating granulomas were more common in the ITB group than the CD group, whereas urban patients with stool change as the first symptom, moderate or severe anemia, thickening of intestinal wall, rectal involvement, skipping distribution, prominent lymphoid aggregates, and irregular glands were more common in CD group than ITB group (P < 0.05). Young patients (age < 30 years) with fever, weakness, fatigue, abdominal mass, intestinal perforation, and emergent operation were more common in ITB group than PIL group, whereas thickening of intestinal wall, malignant lymphocytes, limited distribution, and involvement of small intestine occurred more in PIL group than ITB group (P < 0.05).

Conclusion:

The differential diagnosis of ITB from CD and PIL can be made by a combination of clinical manifestation, endoscopy, and pathological examinations.     

Adoptive Transfer of Human Gingiva‐Derived Mesenchymal Stem Cells Ameliorates Collagen‐Induced Arthritis via Suppression of Th1 and Th17 Cells and Enhancement of Regulatory T Cell Differentiation

Objective

Current approaches offer no cures for rheumatoid arthritis (RA). Accumulating evidence has revealed that manipulation of bone marrow–derived mesenchymal stem cells (BM‐MSCs) may have the potential to control or even prevent RA, but BM‐MSC–based therapy faces many challenges, such as limited cell availability and reduced clinical feasibility. This study in mice with established collagen‐induced arthritis (CIA) was undertaken to determine whether substitution of human gingiva‐derived mesenchymal stem cells (G‐MSCs) would significantly improve the therapeutic effects.

Methods

CIA was induced in DBA/1J mice by immunization with type II collagen and Freund's complete adjuvant. G‐MSCs were injected intravenously into the mice on day 14 after immunization. In some experiments, intraperitoneal injection of PC61 (anti‐CD25 antibody) was used to deplete Treg cells in arthritic mice.

Results

Infusion of G‐MSCs in DBA/1J mice with CIA significantly reduced the severity of arthritis, decreased the histopathology scores, and down‐regulated the production of inflammatory cytokines (interferon‐γ and interleukin‐17A). Infusion of G‐MSCs also resulted in increased levels of CD4+CD39+FoxP3+ cells in arthritic mice. These increases were noted early after infusion in the spleens and lymph nodes, and later after infusion in the synovial fluid. The FoxP3+ Treg cells that were increased in frequency mainly consisted of Helios‐negative cells. When Treg cells were depleted, infusion of G‐MSCs partially interfered with the progression of CIA. Pretreatment of G‐MSCs with a CD39 or CD73 inhibitor significantly reversed the protective effect of G‐MSCs on CIA.

Conclusion

The role of G‐MSCs in controlling the development and severity of CIA mostly depends on CD39/CD73 signals and partially depends on the induction of CD4+CD39+FoxP3+ Treg cells. G‐MSCs provide a promising approach for the treatment of autoimmune diseases.

     

Myogenic lineage differentiated mesenchymal stem cells enhance recovery from dextran sulfate sodium-induced colitis in the rat

Background

Although mounting evidence implicates mesenchymal stem cells (MSCs) in intestinal tissue repair, uncertainty remains concerning the distribution, function, and fate of repopulating MSCs in recipient colonic tissues. Therefore, we investigated the role of transplanted MSCs in the repair phase of DSS colitis.

Methods

LacZ-labeled rat MSCs were transplanted into rats with colitis induced by 4% DSS on day 2. Regular water replaced the DSS solution on day 6. Therapeutic effect was evaluated on day 9 by clinicopathologic and growth factor/cytokine expression profiles. We analyzed the Notch signaling pathway by Western blotting and characterized immunofluorescence of lacZ-labeled MSCs with confocal laser microscopy. In vivo differentiation of MSC was confirmed by transmission electron microscopy (TEM).

Results

Recovery of colitis was modestly but significantly promoted by MSC transplantation due to proceeding cell cycle and inhibiting apoptosis in the epithelia. Tgfa mRNA expression increased significantly, while Notch signaling was inhibited in the colonic tissues with MSC transplantation. ??-Galactosidase-positive cells, which expressed ??-SMA, desmin, and vimentin, were infrequently detected in the lamina propria stroma. DSS exposure in vitro proved to be the most potent inducer for ??-SMA in MSCs where TEM demonstrated myogenic lineage differentiation.

Conclusions

We found that MSCs transplantation modestly promoted the repair of DSS colitis. The donor-derived MSCs were likely reprogrammed to differentiate to myogenic lineage cells by cues from the micro milieu. Further characterization of these cells is warranted as a basis for applying cell-based therapy for inflammatory bowel disease.     

Anal Crohn's Disease

Background: Anal lesions as first manifestation of Crohn's disease can cause difficulties in differential diagnosis especially, when morphologic intestinal changes and, histologically, epitheloid granulomas cannot be demonstrated early. Case Reports: We present a 19-year-old femal patient with atypical anal fissures and a 76-year-old male patient with a circular anal stenosis leading to the diagnosis Crohn's disease which could be proved later. Conclusion: In case of anal fissures or ulcerations Crohn's disease has to be considered, also when endoscopic preexaminations had excluded morphologic equivalents of this disease. We would like to stress that in these cases a repetition of such invasive diagnostic features can be necessary.     

Stem Cell Therapy for Arterial Restenosis: Potential Parameters Contributing to the Success of Bone Marrow-Derived Mesenchymal Stromal Cells

Purpose

Restenosis is a complex and heterogeneous pathophysiological phenomenon occurring in patients submitted to revascularization procedures. Previous studies proved the antirestenotic properties of injected allogenic mesenchymal stromal cells (MSCs) in an experimental model of rat carotid (re)stenosis induced through arteriotomy. In this study we describe some of the effects subsequent to MSC treatment of rats submitted to carotid arteriotomy and possibly responsible for their antirestenotic effect.

Methods

Rat MSCs were isolated from bone marrow, expanded in vitro and characterized. Subsequently, we evaluated the effects of MSC administration via tail vein at 3 and 7?days after carotid arteriotomy both in rat serum and in injured carotids, focusing on DNA oxidative damage (8-oxo-dG detection), cell proliferation index (BrdU incorporation assay), apoptotic index (TUNEL assay), the expression of inflammation- and proliferation-related genes (RT-PCR), the release of growth factors and of inflammation-related cytokines (antibody arrays and ELISA).

Results

MSC administration induced a greater cell proliferation in carotids after arteriotomy, together with an increased level of VEGF in the serum and with the higher expression of VEGF mRNA in injured carotids. Serum analysis also revealed a decreased level of the pro-inflammatory cytokines CXCL1, CXCL5, L-Selectin, ICAM-1 and LIX, and of TIMP1 and SDF-1alpha in MSC-treated rats. The MSC immunomodulatory activity was confirmed by the decreased expression of TLR2 and TLR4 in injured carotids.

Conclusions

MSCs play an immunomodulatory paracrine role when injected in rats submitted to carotid arteriotomy, accompanied by the release of VEGF, possibly contributing to the accelerated repair of the injured vascular wall.     

Improved conduction and increased cell retention in healed MI using mesenchymal stem cells suspended in alginate hydrogel

Introduction

Mesenchymal stem cells (MSCs) have been associated with reduced arrhythmias; however, the mechanism of this action is unknown. In addition, limited retention and survival of MSCs can significantly reduce efficacy. We hypothesized that MSCs can improve impulse conduction and that alginate hydrogel will enhance retention of MSCs in a model of healed myocardial infarction (MI).

Methods and results

Four weeks after temporary occlusion of the left anterior descending artery (LAD), pigs (n?=?13) underwent a sternotomy to access the infarct and then were divided into two studies. In study 1, designed to investigate impulse conduction, animals were administered, by border zone injection, 9–15 million MSCs (n?=?7) or phosphate-buffered saline (PBS) (control MI, n?=?5). Electrogram width measured in the border zone 2 weeks after injections was significantly decreased with MSCs (?30?±?8 ms, p?p?=?NS). Optical mapping from border zone tissue demonstrated that conduction velocity was higher in regions with MSCs (0.49?±?0.03 m/s) compared to regions without MSCs (0.39?±?0.03 m/s, p?w/v) or PBS (n?=?6/group) by border zone injection. Greater MSC retention and survival were observed with 2 % alginate compared to PBS or 1 % alginate. Confocal immunofluorescence demonstrated that MSCs survive and are associated with expression of connexin-43 (Cx43) for either PBS (control), 1 %, or 2 % alginate.

Conclusions

For the first time, we are able to directly associate MSCs with improved impulse conduction and increased retention and survival using an alginate scaffold in a clinically relevant model of healed MI.     

Large‐scale extraction and characterization of CD271+ multipotential stromal cells from trabecular bone in health and osteoarthritis: Implications for bone regeneration strategies based on uncultured or minimally cultured multipotential stromal cells

Objective

To test the hypothesis that CD45^lowCD271+ bone marrow multipotential stromal cells (MSCs) are abundant in the trabecular bone niche and to explore their functional “fitness” in health and osteoarthritis (OA).

Methods

Following enzymatic extraction, MSC release was evaluated using colony‐forming unit–fibroblast (CFU‐F) and colony‐forming unit–osteoblast assays, flow cytometry, and confocal microscopy. CD45^lowCD271+ cells isolated by fluorescence‐activated cell sorting were enumerated and expanded under standard and clonal conditions. Their proliferative and osteogenic potencies were assessed in relation to donor age and compared with those of aspirated CD45^lowCD271+ cells. In vitro and in vivo MSC “aging” was measured using quantitative polymerase chain reaction–based telomere length analysis, and standard differentiation assays were utilized to demonstrate multipotentiality.

Results

Cellular isolates from trabecular bone cavities contained ∼65‐fold more CD45^lowCD271+ cells compared with aspirates (P < 0.0001) (median 1.89% [n = 39] and 0.029% [n = 46], respectively), concordant with increased CFU‐F release. Aspirated and enzymatically released CD45^lowCD271+ cells had identical MSC phenotypes (∼100% CD73+CD105+CD13+, ∼50–60% CD146+CD106+CD166+) and contained large proportions of highly clonogenic multipotential cells. In vitro osteogenic potency of freshly isolated CD45^lowCD271+ cells was comparable with, and often above, that of early‐passage MSCs (8–14%). Their frequency and in vivo telomere status in OA bone were similar to those in bone from age‐matched controls.

Conclusion

Our findings show that CD45^lowCD271+ MSCs are abundant in the trabecular bone cavity and indistinguishable from aspirated CD45^lowCD271+ MSCs. In OA they display aging‐related loss of proliferation but no gross osteogenic abnormality. These findings offer new opportunities for direct study of MSCs in musculoskeletal diseases without the requirement for culture expansion. They are also relevant for direct therapeutic exploitation of prospectively isolated, minimally cultured MSCs in trauma and OA.

     

Evaluation of Early Atherosclerosis in Patients with Inflammatory Bowel Disease

Background

Data regarding early atherosclerosis and inflammatory bowel disease are limited and conflicting results are present.

Aims

The purpose of this study was to evaluate serological and sonographical evidence of subclinical vascular involvement in patients with inflammatory bowel disease.

Methods

Thirty-nine patients with inflammatory bowel disease (20 Crohn's disease, and 19 ulcerative colitis patients) and 31 healthy controls were consecutively enrolled in the study. Flow mediated dilatation of the brachial artery and intima media thickness assessments of the common carotid artery were measured sonographically. Soluble CD40 ligand levels were evaluated. Crohn's disease activity index and modified Truelove-Witt’s criteria were also noted.

Results

Age, sex distribution, serum lipids, smoking status, and intima media thickness of the common carotid artery were similar between the inflammatory bowel disease patients and controls (p > 0.05). However, both endothelium dependent and independent flow mediated dilatation values were significantly impaired in the inflammatory bowel disease group compared with healthy controls (p < 0.05). Erythrocyte sedimentation rate, C-reactive protein and soluble CD40 ligand values were significantly increased in inflammatory bowel disease patients compared with controls (p < 0.05), and soluble CD40 ligand was negatively correlated with flow mediated dilatation (r = ?0.3, p < 0.05). Flow mediated dilatation was significantly predicted from the concentrations of C-reactive protein and soluble CD40 ligand.

Conclusion

Functional atherosclerosis is present in inflammatory bowel disease before early structural changes occur in vasculature. Higher sCD40L may indicate worse vascular outcome for IBD.     

Granulomas as the Most Useful Histopathological Feature in Distinguishing between Crohn's Disease and Intestinal Tuberculosis in Endoscopic Biopsy Specimens

The incidence of Crohn''s disease (CD) is increasing in Chinese populations in whom intestinal tuberculosis (ITB) is prevalent.This study aimed to identify differential diagnostic microscopic and endoscopic characteristics of CD from those of ITB.Patients with CD (N = 52) and patients with ITB (N = 16) diagnosed between 2010 and 2013 were identified. Specimens obtained via endoscopy were analyzed microscopically by a pathologist. The relationship between endoscopic appearance and histopathological features was analyzed. The χ² test, Fisher''s exact probability test, and the Mann-Whitney U test were used.Granulomas were present in 81.3% of ITB cases and in 67.3% of CD cases (P = 0.36). Granulomas in ITB cases were denser than those in CD cases (mean 5.29 ± 4.30 vs. 2.46 ± 3.50 granulomas per 10 low power fields; each low power field = 3.80 mm²; P = 0.005). Granulomas in ITB cases were larger (mean widest diameter, 508 ± 314 μm; range, 100–1100 μm) than those in CD cases (mean widest diameter, 253 ± 197 μm; range, 50–800 μm). Basal plasmacytosis was more common in CD cases than in ITB cases (77.0% vs. 37.5%, P = 0.000). Endoscopy findings such as longitudinal ulcer, aphthous ulcer, and cobblestone appearance were only seen in CD cases (34.6%, 21.2%, and 23.1%, respectively). Granulomas were detected in the majority of cases with longitudinal ulcers (88.9%). Basal plasmacytosis was exclusively detected in cases with longitudinal ulcer and a cobblestone appearance.Characteristics of granulomas maybe the most important distinguishing features between CD and ITB. However, the histopathological characteristics of both diseases may overlap on endoscopic biopsy specimens. An accurate diagnosis should be made that considers clinical, endoscopic features, and pathologic findings.     

Mesenchymal stromal cells improve transplanted islet survival and islet function in a syngeneic mouse model

Aims/hypothesis

Islet transplantation is used therapeutically in a minority of patients with type 1 diabetes. Successful outcomes are hampered by early islet beta cell loss. The adjuvant co-transplantation of mesenchymal stromal cells (MSCs) has the promise to improve islet transplant outcome.

Methods

We used a syngeneic marginal islet mass transplantation model in a mouse model of diabetes. Mice received islets or islets plus 250,000 MSCs. Kidney subcapsule, intra-hepatic and intra-ocular islet transplantation sites were used. Apoptosis, vascularisation, beta cell proliferation, MSC differentiation and laminin levels were determined by immunohistochemical analysis and image quantification post-transplant.

Results

Glucose homeostasis after the transplantation of syngeneic islets was improved by the co-transplantation of MSCs together with islets under the kidney capsule (p?=?0.01) and by intravenous infusion of MSCs after intra-hepatic islet transplantation (p?=?0.05). MSC co-transplantation resulted in reduced islet apoptosis, with reduced numbers of islet cells positive for cleaved caspase 3 being observed 14 days post-transplant. In kidney subcapsule, but not in intra-ocular islet transplant models, we observed increased re-vascularisation rates, but not increased blood vessel density in and around islets co-transplanted with MSCs compared with islets that were transplanted alone. Co-transplantation of MSCs did not increase beta cell proliferation, extracellular matrix protein laminin production or alpha cell numbers, and there was negligible MSC transdifferentiation into beta cells.

Conclusions/interpretation

Co-transplantation of MSCs may lead to improved islet function and survival in the early post-transplantation period in humans receiving islet transplantation.     

Presence of intestinal Mycobacterium avium subspecies paratuberculosis (MAP) DNA is not associated with altered MMP expression in ulcerative colitis

Background

Mycobacterium avium subspecies paratuberculosis (MAP) is suspected to be a causative agent in human Crohn's disease (CD). Recent evidence suggests that pathogenic mycobacteria and MAP can induce the expression of Matrix Metalloproteinases (MMP), which are the main proteases in the pathogenesis of mucosal ulcerations in inflammatory bowel disease (IBD). Within this study we assessed the prevalence of intestinal MAP specific DNA in patients with Crohn's disease, ulcerative colitis (UC), and healthy controls. We further analysed regulation patterns of MMPs in mucosal tissues of UC patients with and without intestinal MAP DNA detection.

Methods

Colonic biopsy samples were obtained from 63 Norwegian and German IBD patients and 21 healthy controls. RNA was quantified by quantitative real-time polymerase chain reaction (PCR) to study MMP gene expression in both pathological and healthy mucosal specimens. The presence of MAP DNA in colonic mucosa was examined using MAP specific PCR.

Results

MAP DNA was detected in 20% of UC patients and 33% of healthy controls but only in 7% of patients with CD. UC patients treated with corticosteroids exhibited a significantly increased frequency of intestinal MAP DNA compared to those not receiving corticosteroids. Expression of MMP-1, -2, -7, -9, -13, -19, -28 and TNF-α did not differ between UC patients with presence of intestinal MAP DNA compared to those without. MMP-2, MMP-9 and MMP-13 were significantly decreased in UC patients receiving corticosteroids.

Conclusions

The presence of intestinal MAP specific DNA is not associated with altered MMP expression in UC in vivo. Corticosteroids are associated with increased detection of intestinal MAP DNA and decreased expression of certain MMPs. Frequent detection of MAP DNA in healthy controls might be attributable to the wide environmental distribution of MAP and its presence in the food-chain.     

Mesenchymal Stem Cells Utilize CXCR4–SDF-1 Signaling for Acute, but Not Chronic, Trafficking to Gastric Mucosal Inflammation

Background

Helicobacter infection is the main risk factor in developing gastric cancer. Mesenchymal stem cells (MSCs) are non-hematopoietic stromal cells, which are able to differentiate into different cell lineages. MSC contribute to cancer development by forming the tumor directly, contributing to the microenvironment, or by promoting angiogenesis and metastasis. CXCR4/SDF-1 axis is used by MSC in trafficking, homing, and engraftment at chronic inflammation sites, and plays an important role in tumorigenesis.

Aim

To determine if CXCR4 receptor has a role in MSC contribution to the development of Helicobacter-mediated gastric cancer.

Methods

SDF-1 and CXCR4 expression in mouse gastric mucosa in the setting of acute and chronic inflammation was measured using RT-PCR. Mouse culture-adapted MSC express CXCR4. Wild-type C57BL/6 mice infected with Helicobacter felis for 6 months or controls were given IV injections of CXCR4 knock-down MSC. Animals were followed for another 4 months. Homing of MSC in the stomach was quantified using RT-PCR. MSC differentiation into gastric epithelia lineages was analyzed using immunohistochemistry and fluorescent in situ hybridization.

Results

CXCR4 and SDF-1 are both upregulated in the settings of Helicobacter-induced chronic gastric inflammation. CXCR4 is fully required for homing of MSC to the stomach in acute gastric inflammation, but only partially in Helicobacter-induced gastric cancer. MSC lead to gastric intraepithelial neoplasia as early as 10 months of Helicobacter infection.

Conclusions

Our results show that MSC have a tumorigenic effect by promoting an accelerated form of gastric cancer in mice. The engraftment of MSC in chronic inflammation is only partially CXCR4-dependent.     

Changes in surface markers of human mesenchymal stem cells during the chondrogenic differentiation and dedifferentiation processes in vitro

Objective

To investigate surface markers showing specific changes during the chondrogenic differentiation and dedifferentiation of human mesenchymal stem cells (MSCs).

Methods

Human MSCs from adult bone marrow were subjected to chondrogenic differentiation in 3‐dimensional (3‐D) alginate culture with or without transforming growth factor β3 (TGFβ3) for 2 weeks, followed by dedifferentiation in monolayer for 1 week. Surface antigens were selected from those previously reported to show changes in expression during dedifferentiation of human articular chondrocytes (HACs).

Results

Flow cytometry was used to identify 3 groups of surface antigens with differential expression patterns that were quite different from those previously reported on HACs. Two groups of antigens were expressed at high levels on human MSCs. The expression of the first group of antigens (CD44, CD58, CD81, CD90, CD105, and CD166) was decreased reversibly by the 3‐D alginate culture and irreversibly in the presence of TGFβ3, except for CD81, which showed reversible changes regardless of TGFβ3. The expression of the second group of antigens (CD49c, CD49e, and CD151) was decreased during chondrogenic differentiation only in the presence of TGFβ3. During all experimental stages, the expression of the third group of antigens (CD14, CD26, CD49f, CD54, CD106, CD119, and CD140a) was maintained at low levels (expressed on <30% of cells), although with some fluctuations.

Conclusion

We speculate that the second group of surface antigens could be negative markers for chondrogenic differentiation of human MSCs.

     

Comparison of Adipose-Derived and Bone Marrow Mesenchymal Stromal Cells in a Murine Model of Crohn’s Disease

Background

Mesenchymal stromal cells (MSCs) have been used in the treatment of Crohn’s disease (CD) because of the immunomodulatory ability.

Aim

The aim of this study was to investigate the therapeutic effect of adipose-derived MSCs (AD-MSCs) and to compare the therapeutic effect of AD-MSCs with that of bone marrow MSCs (BM-MSCs) in a murine model of CD.

Methods

Murine colitis model of CD was created by trinitrobenzene sulfonic acid (TNBS). Twelve hours after treatment with TNBS, the mouse model was injected with MSCs intraperitoneally. Real-time polymerase chain reaction and immunohistochemistry staining were used to measure the expression levels of inflammatory cytokines in colonic tissues to investigate the therapeutic effect of AD-MSCs. The ten-day survival was recorded after infusion of MSCs.

Results

Intraperitoneal injection of MSCs alleviated the clinical and histopathologic severity of intestinal inflammation, and improved the survival of the TNBS-induced mouse model of CD. AD-MSCs could effectively increase the expression of interleukin-10 and reduce the secretion of pro-inflammatory cytokines including tumor necrosis factor-α, interleukin-12, and vascular endothelial growth factor. The mucosal injury was repaired by AD-MSCs. These effects were comparable between AD-MSCs and BM-MSCs.

Conclusions

The therapeutic effect appears similar between AD-MSCs and BM-MSCs in treating CD. AD-MSCs may be a potential alternative of cell-based therapy for CD.

     

Characterization of the human nucleus pulposus cell phenotype and evaluation of novel marker gene expression to define adult stem cell differentiation

Objective

Development of stem cell therapies for regenerating the nucleus pulposus (NP) are hindered by the lack of specific markers by which to distinguish NP cells from articular chondrocytes (ACs). The purpose of this study was to define the phenotype profile of human NP cells using gene expression profiling and to assess whether the identified markers could distinguish mesenchymal stem cell (MSC) differentiation to a correct NP cell phenotype.

Methods

Affymetrix MicroArray analyses were conducted on human NP cells and ACs, and differential expression levels for several positive (NP) and negative (AC) marker genes were validated by real‐time quantitative polymerase chain reaction (PCR) analysis. Novel marker gene and protein expression was also assessed in human bone marrow–derived MSCs (BM‐MSCs) and adipose tissue–derived MSCs (AD‐MSCs) following differentiation in type I collagen gels.

Results

Analysis identified 12 NP‐positive and 36‐negative (AC) marker genes that were differentially expressed ≥20‐fold, and for a subset of them (NP‐positive genes PAX1, FOXF1, HBB, CA12, and OVOS2; AC‐positive genes GDF10, CYTL1, IBSP, and FBLN1), differential expression was confirmed by real‐time quantitative PCR. Differentiated BM‐MSCs and AD‐MSCs demonstrated significant increases in the novel NP markers PAX1 and FOXF1. AD‐MSCs lacked expression of the AC markers IBSP and FBLN1, whereas BM‐MSCs lacked expression of the AC marker IBSP but expressed FBLN1.

Conclusion

This study is the first to use gene expression profiling to identify the human NP cell phenotype. Importantly, these markers can be used to determine the in vitro differentiation of MSCs to an NP‐like, rather than an AC‐like, phenotype. Interestingly, these results suggest that AD‐MSCs may be a more appropriate cell type than BM‐MSCs for use in engineering intervertebral disc tissue.

     

Ecto-5′-nucleotidase promotes invasion, migration and adhesion of human breast cancer cells

Purpose

Associated with many molecules, metastasis includes cell adhesion to extracellular matrix, migration towards specific direction and invasion into local vessel of distant organs. The purpose of the present study was to evaluate the role of ecto-5′-nucleotidase (eN, ecto-5-NT, CD73) generated extracellular adenosine in biologically malignant behaviors of human breast cancer cell lines.

Materials and methods

Two human breast cancer cell lines, T-47D with lower expression of CD73 and MB-MDA-231 with higher expression of CD73, were used to investigate the functions of CD73. The effects of CD73 over-expression on invasion, migration and adhesion were observed in T-47D transfected with pcDNA-NT5E plasmid. The effects of specific CD73 inhibitor, α, ß-methylene ADP (APCP), were observed in MB-MDA-231 cells.

Results

The results showed CD-73 overexpression increased invasion, migration and adhesion to ECM of the pcDNA-NT5E transfected T-47D cells compared to the saline and mock vector controls. The increased cell mobility of CD-73-overexpressed T-47D cells was blocked by APCP. Adenosine increased the mobility of wild type T-47D cells. APCP inhibited the mobility of the MB-MDA-231 cells.

Conclusion

Taken together, our results indicated that CD73 may facilitate the adhesion, migration and invasion of human breast cancer cells through its enzyme activity of generating adenosine. This study provided a possibly molecular mechanism of metastasis of breast carcinoma.     

Adamantinomatous craniopharyngiomas express tumor stem cell markers in cells with activated Wnt signaling: further evidence for the existence of a tumor stem cell niche?

Introduction

Early disease onset, clinical manifestation, histomorphology, and increased tendency to relapse distinguish the adamantinomatous craniopharyngioma (adaCP) from the more favorable papillary variant (papCP). A molecular hallmark of adaCP is the activated Wnt signaling pathway indicated by nuclear β-catenin accumulation in a subset of tumor cells. A mouse model recently illustrated that these cells are the driving force in tumorigenesis of adaCP. This observation and the peculiar growth pattern points to the existence of a specific tumor stem cell (TSC) population in human CP.

Materials and Methods

To prove this hypothesis, the TSC markers CD133 (Prominin1) and CD44 were examined in papCP (n = 8) and adaCP (n = 25) on mRNA level using quantitative real time PCR of total tumor RNA. Furthermore, we investigated protein expression performing immunohistochemical analyses of formalin-fixed paraffin embedded tumor samples.

Results

PapCP revealed a homogenous CD44 expression pattern predominantly at the cell membrane, whereas CD133 labeling was hardly detectable. In adaCP, on the other hand all markers were consistently and predominantly co-expressed in nuclear β-catenin accumulating cell clusters, which was confirmed by double immunofluorescence staining. Overall expression of CD44 was significantly decreased in adaCP versus papCP, whereas CD133 showed significantly higher protein and mRNA levels in adaCP.

Conclusions

Our results indicate tumor stem cell-like characteristics of β-catenin accumulating cell clusters in adaCP, which may represent a tumor stem cell niche and might contribute to tumor recurrence. The potential impact of these special cell groups in regard to future CP management, including postoperative follow-up and additional treatment remains to be explored.     

NOD2 exonic variations in Iranian Crohn's disease patients

Purpose

The NOD2 gene is known to have a strong association with Crohn??s disease, but different trends were reported in occurrence of NOD2 variants in distinct ethnicities. The aim of this study was to assess all exonic sequences of the NOD2 gene in Iranian Crohn's disease patients and healthy controls to identify any existing variation and evaluate their association with Crohn's disease.

Methods

A total of 90 non-related Crohn's disease patients and 120 sex- and age-matched healthy controls of Iranian origin were enrolled in this study. The participants were referred to a tertiary center in a 2-year period (2006?C2008). The exonic regions of the NOD2 gene were amplified by polymerase chain reaction and evaluated by direct sequencing.

Results

A total of 21 sequence variations were identified among all exonic regions of the NOD2 gene, of which eight had an allele frequency of more than 5%. Eight new mutations (one in exon 2 and seven in exon 4) were observed. The three main variants (R702W, G908R, and 1007fs) showed allele frequencies of 13.3%, 2.2%, and 1.7%, respectively. Three new variations (P371T, A794P, and Q908H) and R702W mutation were significantly more frequent in Crohn's disease patients compared to controls.

Conclusions

Eight novel mutations were identified in the NOD2 exons, but the pathophysiological importance of these variants remains unclear. Iranian patients with their different genetic reservoirs may demonstrate some novel characteristics for disease susceptibility.