Examination of FGFRL1 as a candidate gene for diaphragmatic defects at chromosome 4p16.3 shows that Fgfrl1 null mice have reduced expression of Tpm3, sarcomere genes and Lrtm1 in the diaphragm

Fgfrl1 (also known as Fgfr5; OMIM 605830) homozygous null mice have thin, amuscular diaphragms and die at birth because of diaphragm hypoplasia. FGFRL1 is located at 4p16.3, and this chromosome region can be deleted in patients with congenital diaphragmatic hernia (CDH). We examined FGFRL1 as a candidate gene for the diaphragmatic defects associated with 4p16.3 deletions and re-sequenced this gene in 54 patients with CDH. We confirmed six known coding single nucleotide polymorphisms (SNPs): c.209G > A (p.Pro20Pro), c.977G > A (p.Pro276Pro), c.1040T > C (p.Asp297Asp), c.1234C > A (p.Pro362Gln), c.1420G > T (p.Arg424Leu), and c.1540C > T (p.Pro464Leu), but we did not identify any gene mutations. We genotyped additional CDH patients for four of these six SNPs, including the three non-synonymous SNPs, to make a total of 200 chromosomes, and found that the allele frequency for the four SNPs, did not differ significantly between patients and normal controls (p > or = 0.05). We then used Affymetrix Genechip Mouse Gene 1.0 ST arrays and found eight genes with significantly reduced expression levels in the diaphragms of Fgfrl1 homozygous null mice when compared with wildtype mice-Tpm3, Fgfrl1 (p = 0.004), Myl2, Lrtm1, Myh4, Myl3, Myh7 and Hephl1. Lrtm1 is closely related to Slit3, a protein associated with herniation of the central tendon of the diaphragm in mice. The Slit proteins are known to regulate axon branching and cell migration, and inhibition of Slit3 reduces cell motility and decreases the expression of Rac and Cdc42, two genes that are essential for myoblast fusion. Further studies to determine if Lrtm1 has a similar function to Slit3 and if reduced Fgfrl1 expression can cause diaphragm hypoplasia through a mechanism involving decreased myoblast motility and/or myoblast fusion, seem indicated.

Inhibition of tissue transglutaminase sensitizes TRAIL-resistant lung cancer cells through upregulation of death receptor 5

Tissue transglutaminase (TG2) is implicated in cellular processes such as apoptosis and cell migration. Its acyl transferase activity cross-links certain proteins, among them transcription factors were described. We show here that the TG2 inhibitor KCC009 reversed resistance to tumor necrosis factor-related apoptosis-inducing factor (TRAIL) in lung cancer cells. Sensitization required upregulation of death receptor 5 (DR5) but not of death receptor 4. Upregulation of DR5 involved the first intron of the DR5 gene albeit it was independent from p53 and nuclear factor kappa B. In conclusion, inhibition of tissue transglutaminase provides an interesting strategy for sensitization to TRAIL-induced apoptosis in p53-deficient lung cancer cells.

Nedd4-1 and beta-arrestin-1 are key regulators of Na+/H+ exchanger 1 ubiquitylation, endocytosis, and function

The ubiquitously expressed mammalian Na(+)/H(+) exchanger 1 (NHE1) controls cell volume and pH but is also critically involved in complex biological processes like cell adhesion, cell migration, cell proliferation, and mechanosensation. Pathways controlling NHE1 turnover at the plasma membrane, however, are currently unclear. Here, we demonstrate that NHE1 undergoes ubiquitylation at the plasma membrane by a process that is unprecedented for a mammalian ion transport protein. This process requires the adapter protein ?-arrestin-1 that interacts with both the E3 ubiquitin ligase Nedd4-1 and the NHE1 C terminus. Truncation of NHE1 C terminus to amino acid 550 abolishes binding to ?-arrestin-1 and NHE1 ubiquitylation. Overexpression of ?-arrestin-1 or of wild type but not ligase-dead Nedd4-1 increases NHE1 ubiquitylation. siRNA-mediated knock-down of Nedd4-1 or ?-arrestin-1 reduces NHE1 ubiquitylation and endocytosis leading to increased NHE1 surface levels. Fibroblasts derived from ?-arrestin-1 and Nedd4-1 knock-out mice show loss of NHE1 ubiquitylation, increased plasmalemmal NHE1 levels and greatly enhanced NHE1 transport compared with wild-type fibroblasts. These findings reveal Nedd4-1 and ?-arrestin-1 as key regulators of NHE1 ubiquitylation, endocytosis, and function. Our data suggest a broader role for ?-arrestins in the regulation of membrane ion transport proteins than currently known.

Intra-arterial injection of neural stem cells using a microneedle technique does not cause microembolic strokes

Intra-arterial (IA) injection represents an experimental avenue for minimally invasive delivery of stem cells to the injured brain. It has however been reported that IA injection of stem cells carries the risk of reduction in cerebral blood flow (CBF) and microstrokes. Here we evaluate the safety of IA neural progenitor cell (NPC) delivery to the brain. Cerebral blood flow of rats was monitored during IA injection of single cell suspensions of NPCs after stroke. Animals received 1 × 10(6) NPCs either injected via a microneedle (microneedle group) into the patent common carotid artery (CCA) or via a catheter into the proximally ligated CCA (catheter group). Controls included saline-only injections and cell injections into non-stroked sham animals. Cerebral blood flow in the microneedle group remained at baseline, whereas in the catheter group a persistent (15 minutes) decrease to 78% of baseline occurred (P<0.001). In non-stroked controls, NPCs injected via the catheter method resulted in higher levels of Iba-1-positive inflammatory cells (P=0.003), higher numbers of degenerating neurons as seen in Fluoro-Jade C staining (P<0.0001) and ischemic changes on diffusion weighted imaging. With an appropriate technique, reduction in CBF and microstrokes do not occur with IA transplantation of NPCs.

Genome-wide association study of intracranial aneurysm identifies three new risk loci

Saccular intracranial aneurysms are balloon-like dilations of the intracranial arterial wall; their hemorrhage commonly results in severe neurologic impairment and death. We report a second genome-wide association study with discovery and replication cohorts from Europe and Japan comprising 5,891 cases and 14,181 controls with approximately 832,000 genotyped and imputed SNPs across discovery cohorts. We identified three new loci showing strong evidence for association with intracranial aneurysms in the combined dataset, including intervals near RBBP8 on 18q11.2 (odds ratio (OR) = 1.22, P = 1.1 x 10(-12)), STARD13-KL on 13q13.1 (OR = 1.20, P = 2.5 x 10(-9)) and a gene-rich region on 10q24.32 (OR = 1.29, P = 1.2 x 10(-9)). We also confirmed prior associations near SOX17 (8q11.23-q12.1; OR = 1.28, P = 1.3 x 10(-12)) and CDKN2A-CDKN2B (9p21.3; OR = 1.31, P = 1.5 x 10(-22)). It is noteworthy that several putative risk genes play a role in cell-cycle progression, potentially affecting the proliferation and senescence of progenitor-cell populations that are responsible for vascular formation and repair.

Enhanced activity of meprin-?, a pro-migratory and pro-angiogenic protease, in colorectal cancer

Meprin-α is a metalloprotease overexpressed in cancer cells, leading to the accumulation of this protease in a subset of colorectal tumors. The impact of increased meprin-α levels on tumor progression is not known. We investigated the effect of this protease on cell migration and angiogenesis in vitro and studied the expression of meprin-α mRNA, protein and proteolytic activity in primary tumors at progressive stages and in liver metastases of patients with colorectal cancer, as well as inhibitory activity towards meprin-α in sera of cancer patient as compared to healthy controls. We found that the hepatocyte growth factor (HGF)-induced migratory response of meprin-transfected epithelial cells was increased compared to wild-type cells in the presence of plasminogen, and that the angiogenic response in organ-cultured rat aortic explants was enhanced in the presence of exogenous human meprin-α. In patients, meprin-α mRNA was expressed in colonic adenomas, primary tumors UICC (International Union Against Cancer) stage I, II, III and IV, as well as in liver metastases. In contrast, the corresponding protein accumulated only in primary tumors and liver metastases, but not in adenomas. However, liver metastases lacked meprin-α activity despite increased expression of the corresponding protein, which correlated with inefficient zymogen activation. Sera from cancer patients exhibited reduced meprin-α inhibition compared to healthy controls. In conclusion, meprin-α activity is regulated differently in primary tumors and metastases, leading to high proteolytic activity in primary tumors and low activity in liver metastases. By virtue of its pro-migratory and pro-angiogenic activity, meprin-α may promote tumor progression in colorectal cancer.

MicroRNA-29b is involved in the Src-ID1 signaling pathway and is dysregulated in human lung adenocarcinoma

The c-Src kinase regulates cancer cell invasion through inhibitor of DNA binding/differentiation 1 (ID1). Src and ID1 are frequently overexpressed in human lung adenocarcinoma. The current study aimed at identifying microRNAs (miRNAs) involved in the Src-ID1 signaling in lung cancer. Incubation of lung cancer cells with the Src inhibitor saracatinib led to the upregulation of several miRNAs including miR-29b, which was the most highly upregulated miRNA with predicted binding to the ID1 3'-untranslated region (UTR). Luciferase reporter assays confirmed direct binding of miR-29b to the ID1 3'-UTR. Expression of miR-29b suppressed ID1 levels and significantly reduced migration and invasion. Expression of antisense-miR-29b (anti-miR-29b), on the other hand, enhanced ID1 mRNA and protein levels, and significantly increased lung cancer cell migration and invasion, a hallmark of the Src-ID1 pathway. The ectopic expression of ID1 in miR-29b-overexpressing cells was able to rescue the migratory potential of these cells. Both, anti-miR-29b and ID1 overexpression diminished the effects of the Src inhibitors saracatinib and dasatinib on migration and invasion. Saracatinib and dasatinib decreased c-Myc transcriptional repression on miR-29b and led to increased ID1 protein levels, whereas forced expression of c-Myc repressed miR-29b and induced ID1. In agreement, we showed direct recruitment of c-Myc to the miR-29b promoter. miR-29b was significantly downregulated in primary lung adenocarcinoma samples compared with matched alveolar lung tissue, and miR-29b expression was a significant prognostic factor for patient outcome. These results suggest that miR-29b is involved in the Src-ID1 signaling pathway, is dysregulated in lung adenocarcinoma and is a potential predictive marker for Src kinase inhibitors.

Human neural stem cells enhance structural plasticity and axonal transport in the ischaemic brain

Stem cell transplantation promises new hope for the treatment of stroke although significant questions remain about how the grafted cells elicit their effects. One hypothesis is that transplanted stem cells enhance endogenous repair mechanisms activated after cerebral ischaemia. Recognizing that bilateral reorganization of surviving circuits is associated with recovery after stroke, we investigated the ability of transplanted human neural progenitor cells to enhance this structural plasticity. Our results show the first evidence that human neural progenitor cell treatment can significantly increase dendritic plasticity in both the ipsi- and contralesional cortex and this coincides with stem cell-induced functional recovery. Moreover, stem cell-grafted rats demonstrated increased corticocortical, corticostriatal, corticothalamic and corticospinal axonal rewiring from the contralesional side; with the transcallosal and corticospinal axonal sprouting correlating with functional recovery. Furthermore, we demonstrate that axonal transport, which is critical for both proper axonal function and axonal sprouting, is inhibited by stroke and that this is rescued by the stem cell treatment, thus identifying another novel potential mechanism of action of transplanted cells. Finally, we established in vitro co-culture assays in which these stem cells mimicked the effects observed in vivo. Through immunodepletion studies, we identified vascular endothelial growth factor, thrombospondins 1 and 2, and slit as mediators partially responsible for stem cell-induced effects on dendritic sprouting, axonal plasticity and axonal transport in vitro. Thus, we postulate that human neural progenitor cells aid recovery after stroke through secretion of factors that enhance brain repair and plasticity.

Patterns of molecular response to and relapse after combination of sorafenib, idarubicin, and cytarabine in patients with FLT3 mutant acute myeloid leukemia

BACKGROUND: FMS-like tyrosine kinase 3 (FLT3) is a class III receptor tyrosine kinase involved in hematopoietic progenitor cell development. Mutations of FLT3 have been reported in about a third of patients with acute myeloid leukemia (AML), and inhibitors of FLT3 are of clinical interest. Sorafenib is an orally active multikinase inhibitor with potent activity against FLT3 and the Raf/ERK/MEK kinase pathway. METHODS: We studied the patterns of molecular response and relapse in 18 patients with mutated FLT3 treated with the combination of sorafenib, idarubicin, and cytarabine. RESULTS: The median follow-up was 9 months. Sixteen patients achieved complete remission (CR), and the other 2 patients achieved CR but lacked platelet recovery for an overall response rate of 100%. Ten patients had their FLT3-mutated clone eradicated, with 6 patients who showed some residual FLT3-mutated cells, and 2 patients who showed persistent FLT3-mutated cells. The elimination of FLT3-mutated population at the time of morphologic CR, however, was not predictive of relapse. After a median follow-up of 9 months (range, 1-16 months), 10 (55%) patients had relapsed, with a median CR duration of 8.8 months (range, 1-9.5 months). By DNA sequencing, there was no evidence of an acquired FLT3 point mutation at the time of relapse in 7 patients tested, which suggested the presence of other mechanisms of sorafenib resistance. CONCLUSION: Sorafenib, combined with chemotherapy, is effective in attaining CR, but relapses still occur.

Vascular endothelial growth factor induces contralesional corticobulbar plasticity and functional neurological recovery in the ischemic brain

Vascular endothelial growth factor (VEGF) is a potent angiogenic factor, which also has neuroprotective activity. In view of these dual actions on vessels and neurons, we were interested whether VEGF promotes long distance axonal plasticity in the ischemic brain. Herein, we show that VEGF promotes neurological stroke recovery in mice when delivered in a delayed way starting 3 days after middle cerebral artery occlusion. Using anterograde tract-tracing experiments that we combined with histochemical and molecular biological studies, we demonstrate that although VEGF promoted angiogenesis predominantly in the ischemic hemisphere, pronounced axonal sprouting was induced by VEGF in the contralesional, but not the ipsilesional corticobulbar system. Corticobulbar plasticity was accompanied by the deactivation of the matrix metalloproteinase MMP9 in the lesioned hemisphere and the transient downregulation of the axonal growth inhibitors NG2 proteoglycan and brevican and the guidance molecules ephrin B1/2 in the contralesional hemisphere. The regulation of matrix proteinases, growth inhibitors, and guidance molecules offers insights how brain plasticity is controlled in the ischemic brain.

Chemotaxis of T-cells after infection of human choroid plexus papilloma cells with Echovirus 30 in an in vitro model of the blood-cerebrospinal fluid barrier

Enterovirus is the most common pathogen causing viral meningitis especially in children. Besides the blood-brain barrier (BBB) the choroid plexus, which forms the blood-cerebrospinal-fluid (CSF) barrier (BCSFB), was shown to be involved in the pathogenesis of enteroviral meningitis. In a human in vitro model of the BCSFB consisting of human choroid plexus papilloma cells (HIBCPP), the permissiveness of plexus epithelial cells for Echovirus 30 (EV30) was analyzed by immunoblotting and quantitative real-time PCR (Q-PCR). HIBCPP could be directly infected by EV30 from the apical as well as from the physiological relevant basolateral side. During an infection period of 5h no alterations of barrier function and cell viability could be observed. Analysis of the cytokine/chemokine-profile following enteroviral infection with a cytometric bead array (CBA) and Q-PCR revealed an enhanced secretion of PanGRO (CXCL1, CXCL2 and CXCL3), IL8 and CCL5. Q-PCR showed a significant upregulation of CXCL1, CXCL2 and CXCL3 in a time dependant manner. However, there was only a minor effect of HIBCPP-infection with EV30 on transepithelial T lymphocyte migration with or without the chemoattractant CXCL12. Moreover, CXCL3 did not significantly enhance T cell migrations. Therefore additional factors must be involved for the in vivo reported enhanced T cell migration into the CNS in the context of enteroviral meningitis. As HIBCPP are permissive for infection with EV30, they constitute a valuable human in vitro model to study viral infection at the BCSFB.

Antimicrobial activities of chemokines: not just a side-effect?

The large family of chemoattractant cytokines (chemokines) embraces multiple, in part unrelated functions that go well beyond chemotaxis. Undoubtedly, the control of immune cell migration (chemotaxis) is the single, unifying response mediated by all chemokines, which involves the sequential engagement of chemokine receptors on migrating target cells. However, numerous additional cellular responses are mediated by some (but not all) chemokines, including angiogenesis, tumor cell growth, T-cell co-stimulation, and control of HIV-1 infection. The recently described antimicrobial activity of several chemokines is of particular interest because antimicrobial peptides are thought to provide an essential first-line defense against invading microbes at the extremely large body surfaces of the skin, lungs, and gastrointestinal-urinary tract. Here we summarize the current knowledge about chemokines with antimicrobial activity and discuss their potential contribution to the control of bacterial infections that may take place at the earliest stage of antimicrobial immunity. In the case of homeostatic chemokines with antimicrobial function, such as CXCL14, we propose an immune surveillance function in healthy epithelial tissues characterized by low-level exposure to environmental microbes. Inflammatory chemokines, i.e., chemokines that are produced in tissue cells in response to microbial antigens (such as pathogen-associated molecular patterns) may be more important in orchestrating the cellular arm in antimicrobial immunity.

A homeopathic remedy from arnica, marigold, St. John's wort and comfrey accelerates in vitro wound scratch closure of NIH 3T3 fibroblasts

Background Drugs of plant origin such as Arnica montana, Calendula officinalis or Hypericum perforatum have been frequently used to promote wound healing. While their effect on wound healing using preparations at pharmacological concentrations was supported by several in vitro and clinical studies, investigations of herbal homeopathic remedies on wound healing process are rare. The objective of this study was to investigate the effect of a commercial low potency homeopathic remedy Similasan® Arnica plus Spray on wound closure in a controlled, blind trial in vitro. Methods We investigated the effect of an ethanolic preparation composed of equal parts of Arnica montana 4x, Calendula officinalis 4x, Hypericum perforatum 4x and Symphytum officinale 6x (0712–2), its succussed hydroalcoholic solvent (0712–1) and unsuccussed solvent (0712–3) on NIH 3T3 fibroblasts. Cell viability was determined by WST-1 assay, cell growth using BrdU uptake, cell migration by chemotaxis assay and wound closure by CytoSelect ™Wound Healing Assay Kit which generated a defined “wound field”. All assays were performed in three independent controlled experiments. Results None of the three substances affected cell viability and none showed a stimulating effect on cell proliferation. Preparation (0712–2) exerted a stimulating effect on fibroblast migration (31.9%) vs 14.7% with succussed solvent (0712–1) at 1:100 dilutions (p < 0.001). Unsuccussed solvent (0712–3) had no influence on cell migration (6.3%; p > 0.05). Preparation (0712–2) at a dilution of 1:100 promoted in vitro wound closure by 59.5% and differed significantly (p < 0.001) from succussed solvent (0712–1), which caused 22.1% wound closure. Conclusion Results of this study showed that the low potency homeopathic remedy (0712–2) exerted in vitro wound closure potential in NIH 3T3 fibroblasts. This effect resulted from stimulation of fibroblasts motility rather than of their mitosis.

Stem Cells From Umbilical Cord Wharton's Jelly From Preterm Birth Have Neuroglial Differentiation Potential

Objective:The aim of the study is to determine the neuroglial differentiation potential of human Wharton's jelly-derived mesenchymal stem cells (WJ-MSCs) from preterm birth when compared to term delivery.Study Design:The WJ-MSCs from umbilical cords of preterm birth and term controls were isolated and induced into neural progenitors. The cells were analyzed for neuroglial markers by flow cytometry, real-time polymerase chain reaction, and immunocytochemistry. Results:Independent of gestational age, a subset of WJ-MSC displayed the neural progenitor cell markers Nestin and Musashi-1 and the mature neural markers microtubule-associated protein 2, glial fibrillary acidic protein, and myelin basic protein. Neuroglial induction of WJ-MSCs from term and preterm birth resulted in the enhanced transcription of Nestin and Musashi-1.Conclusions:Undifferentiated WJ-MSCs from preterm birth express neuroglial markers and can be successfully induced into neural progenitors similar to term controls. Their potential use as cellular graft in neuroregenerative therapy for peripartum brain injury in preterm birth has to be tested.

Multicycle dose-intensive chemotherapy for women with high-risk primary breast cancer: results of International Breast Cancer Study Group Trial 15-95

PURPOSE: To compare adjuvant dose-intensive epirubicin and cyclophosphamide chemotherapy administered with filgrastim and progenitor cell support (DI-EC) with standard-dose anthracycline-based chemotherapy (SD-CT) for patients with early-stage breast cancer and a high risk of relapse, defined as stage II disease with 10 or more positive axillary nodes; or an estrogen receptor-negative or stage III tumor with five or more positive axillary nodes. PATIENTS AND METHODS: Three hundred forty-four patients were randomized after surgery to receive seven cycles of SD-CT over 22 weeks, or three cycles of DI-EC (epirubicin 200 mg/m2 plus cyclophosphamide 4 gm/m2 with filgrastim and progenitor cell support) over 6 weeks. All patients were assigned tamoxifen at the completion of chemotherapy. The primary end point was disease-free survival (DFS). RESULTS: After a median follow-up of 5.8 years (range, 3 to 8.4 years), 188 DFS events had occurred (DI-EC, 86 events; SD-CT, 102 events). The 5-year DFS was 52% for DI-EC and 43% for SD-CT, with hazard ratio of DI-EC compared with SD-CT of 0.77 (95% CI, 0.58 to 1.02; P = .07). The 5-year overall survival was 70% for DI-EC and 61% for SD-CT, with a hazard ratio of 0.79 (95% CI, 0.56 to 1.11; P = .17). There were eight cases (5%) of anthracycline-induced cardiomyopathy (two fatal) among those who received DI-EC. Women with hormone receptor-positive tumors benefited significantly from DI-EC. CONCLUSION: There was a trend in favor of DI-EC with respect to disease-free survival. A larger trial or meta-analysis will be required to reveal the true effect of dose-intensive therapy.