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Sample records for cxcr4 chemokine receptor

  1. Study of structure function correlation of chemokine receptor CXCR4

    Institute of Scientific and Technical Information of China (English)

    ZHENG Hong; Stephen C PEIPER; ZHU Xi-hua

    2002-01-01

    Objective: To explore the correlation between structure domains and functions of chemokine receptor CXCR4. Methods: After the establishment of wild type chemokine receptor CXCR4 and CXCR2 expressing cell lines, 5 CXCR4/CXCR2 chimeras, 2 CXCR4 mutants were stably expressed on CHO cell line.Binding activities of all variants with the ligand, recombinant human SDF-1β, signal transduction ability after stimulation and their function as coreceptor for HIV-1 were studied with ligand-binding assay, Cytosensor/microphysiometry and cell-cell reporter gene fusion assay. Results: Among all 7 changed CXCR4 receptors, 3 chimeras (2444a, 4442, 4122), and 1 mutant (CXCR4-Tr) bond with SDF-1β in varying degrees, of which only 2444a totally and CXCR4-Tr partially maintain signaling. All changed receptors except for 4222 could act as coreceptors for HIV-1(LAI) in varying degrees. Conclusion: Several structure domains of CXCR4 are involved in the binding with SDF-1β, among which, N-terminal extracellular domain has high affinity of binding with SDF-1β, and the 3rd extracellular loop contributes to the binding, too. Although the C-terminal intracellular domain has no association with the maintenance of the overall structure of the receptor and ligand binding capability, the signaling is decreased when this domain is truncated. For CXCR4 signaling, not only is the conserved motif DRY box needed, but also the characterized conformation of the whole molecule must be formed when activation is required. There are some overlaps between SDF-1β binding domains and coreceptor function domains in molecular structure of CXCR4.

  2. Identification and profiling of CXCR3-CXCR4 chemokine receptor heteromer complexes

    NARCIS (Netherlands)

    Watts, A. O.; van Lipzig, M. M. H.; Jaeger, W. C.; Seeber, R. M.; van Zwam, M.; Vinet, J.; van der Lee, M. M. C.; Siderius, M.; Zaman, G. J. R.; Boddeke, H. W. G. M.; Smit, M. J.; Pfleger, K. D. G.; Leurs, R.; Vischer, H. F.

    2013-01-01

    Background and Purpose The C-X-C chemokine receptors 3 (CXCR3) and C-X-C chemokine receptors 4 (CXCR4) are involved in various autoimmune diseases and cancers. Small antagonists have previously been shown to cross-inhibit chemokine binding to CXCR4, CC chemokine receptors 2 (CCR2) and 5 (CCR5) heter

  3. Strong Expression of Chemokine Receptor CXCR4 by Renal Cell Carcinoma Correlates with Advanced Disease

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    Thomas C. Wehler

    2008-01-01

    Full Text Available Diverse chemokines and their receptors have been associated with tumor growth, tumor dissemination, and local immune escape. In different tumor entities, the level of chemokine receptor CXCR4 expression has been linked with tumor progression and decreased survival. The aim of this study was to evaluate the influence of CXCR4 expression on the progression of human renal cell carcinoma. CXCR4 expression of renal cell carcinoma was assessed by immunohistochemistry in 113 patients. Intensity of CXCR4 expression was correlated with both tumor and patient characteristics. Human renal cell carcinoma revealed variable intensities of CXCR4 expression. Strong CXCR4 expression of renal cell carcinoma was significantly associated with advanced T-status (P=.039, tumor dedifferentiation (P = .0005, and low hemoglobin (P = .039. In summary, strong CXCR4 expression was significantly associated with advanced dedifferentiated renal cell carcinoma.

  4. Diversity and Inter-Connections in the CXCR4 Chemokine Receptor/Ligand Family: Molecular Perspectives.

    Science.gov (United States)

    Pawig, Lukas; Klasen, Christina; Weber, Christian; Bernhagen, Jürgen; Noels, Heidi

    2015-01-01

    CXCR4 and its ligand CXCL12 mediate the homing of progenitor cells in the bone marrow and their recruitment to sites of injury, as well as affect processes such as cell arrest, survival, and angiogenesis. CXCL12 was long thought to be the sole CXCR4 ligand, but more recently the atypical chemokine macrophage migration inhibitory factor (MIF) was identified as an alternative, non-cognate ligand for CXCR4 and shown to mediate chemotaxis and arrest of CXCR4-expressing T-cells. This has complicated the understanding of CXCR4-mediated signaling and associated biological processes. Compared to CXCL12/CXCR4-induced signaling, only few details are known on MIF/CXCR4-mediated signaling and it remains unclear to which extent MIF and CXCL12 reciprocally influence CXCR4 binding and signaling. Furthermore, the atypical chemokine receptor 3 (ACKR3) (previously CXCR7) has added to the complexity of CXCR4 signaling due to its ability to bind CXCL12 and MIF, and to evoke CXCL12- and MIF-triggered signaling independently of CXCR4. Also, extracellular ubiquitin (eUb) and the viral protein gp120 (HIV) have been reported as CXCR4 ligands, whereas viral chemokine vMIP-II (Herpesvirus) and human β3-defensin (HBD-3) have been identified as CXCR4 antagonists. This review will provide insight into the diversity and inter-connections in the CXCR4 receptor/ligand family. We will discuss signaling pathways initiated by binding of CXCL12 vs. MIF to CXCR4, elaborate on how ACKR3 affects CXCR4 signaling, and summarize biological functions of CXCR4 signaling mediated by CXCL12 or MIF. Also, we will discuss eUb and gp120 as alternative ligands for CXCR4, and describe vMIP-II and HBD-3 as antagonists for CXCR4. Detailed insight into biological effects of CXCR4 signaling und underlying mechanisms, including diversity of CXCR4 ligands and inter-connections with other (chemokine) receptors, is clinically important, as the CXCR4 antagonist AMD3100 has been approved as stem cell mobilizer in specific

  5. Chemokine receptor CXCR4 downregulated by von Hippel-Lindau tumour suppressor pVHL

    DEFF Research Database (Denmark)

    Staller, Peter; Sulitkova, Jitka; Lisztwan, Joanna

    2003-01-01

    Organ-specific metastasis is governed, in part, by interactions between chemokine receptors on cancer cells and matching chemokines in target organs. For example, malignant breast cancer cells express the chemokine receptor CXCR4 and commonly metastasize to organs that are an abundant source...... regulates CXCR4 expression owing to its capacity to target hypoxia-inducible factor (HIF) for degradation under normoxic conditions. This process is suppressed under hypoxic conditions, resulting in HIF-dependent CXCR4 activation. An analysis of clear cell renal carcinoma that manifests mutation of the VHL...

  6. Consequences of ChemR23 heteromerization with the chemokine receptors CXCR4 and CCR7.

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    Cédric de Poorter

    Full Text Available Recent studies have shown that heteromerization of the chemokine receptors CCR2, CCR5 and CXCR4 is associated to negative binding cooperativity. In the present study, we build on these previous results, and investigate the consequences of chemokine receptor heteromerization with ChemR23, the receptor of chemerin, a leukocyte chemoattractant protein structurally unrelated to chemokines. We show, using BRET and HTRF assays, that ChemR23 forms homomers, and provide data suggesting that ChemR23 also forms heteromers with the chemokine receptors CCR7 and CXCR4. As previously described for other chemokine receptor heteromers, negative binding cooperativity was detected between ChemR23 and chemokine receptors, i.e. the ligands of one receptor competed for the binding of a specific tracer of the other. We also showed, using mouse bone marrow-derived dendritic cells prepared from wild-type and ChemR23 knockout mice, that ChemR23-specific ligands cross-inhibited CXCL12 binding on CXCR4 in a ChemR23-dependent manner, supporting the relevance of the ChemR23/CXCR4 interaction in native leukocytes. Finally, and in contrast to the situation encountered for other previously characterized CXCR4 heteromers, we showed that the CXCR4-specific antagonist AMD3100 did not cross-inhibit chemerin binding in cells co-expressing ChemR23 and CXCR4, demonstrating that cross-regulation by AMD3100 depends on the nature of receptor partners with which CXCR4 is co-expressed.

  7. Chemokine receptor CXCR4-prognostic factor for gastrointestinal tumors

    Institute of Scientific and Technical Information of China (English)

    Carl C Schimanski; Peter R Galle; Markus Moehler

    2008-01-01

    To review the implication of CXCR4 for gastrointestinal cancer,a "Pubmed" analysis was performed in order to evaluate the relevance of CXCR4 and its ligands for gastrointestinal cancers.Search terms applied were "cancer,malignoma,esophageal,gastric,colon,colorectal,hepatic,pancreatic,CXCR4,SDF-1α,and SDF-1β"; CXCR4 expression correlated with dissemination of diverse gastrointestinal malignomas.The CXCR4 ligand SDF-1α might act as "chemorepellent"while SDF-1β might act as "chemorepellent" for CTLs,inducing tumor rejection.The paracrine expression of SDF-1α was furthermore closely associated with neoangiogenesis.CXCR4 and its ligands influence the dissemination,immune rejection,and neoangiogenesis of human gastrointestinal cancers.Inhibition of CXCR4 might be an interesting therapeutic option.

  8. Bicyclams, selective antagonists of the human chemokine receptor CXCR4, potently inhibit feline immunodeficiency virus replication

    NARCIS (Netherlands)

    Horzinek, M.C.; Egberink, H.F.; Clercq, E. de; Vliet, A.L.W. van; Balzarini, J.; Bridger, G.J.; Henson, G.; Schols, D.

    1999-01-01

    Bicyclams are low-molecular-weight anti-human immunodeficiency virus (HIV) agents that have been shown to act as potent and selective CXC chemokine receptor 4 (CXCR4) antagonists. Here, we demonstrate that bicyclams are potent inhibitors of feline immunodeficiency virus (FIV) replication when evalua

  9. Expressions of chemokine receptor CXCR4 and its ligand CXCL12 in salivary adenoid cystic carcinoma

    Institute of Scientific and Technical Information of China (English)

    徐晓刚; 吕春堂; 周中华

    2004-01-01

    Objective: To examine expressions of chemokine receptor CXCR4 and its ligand CXCL12 in primary focus and lymphogenous metastasis of salivary adenoid cystic carcinoma (ACC) with lung metastasis. Methods: Using immunohistochemical hypersensitivity catalyzed signal amplification (CSA), expressions of chemokine receptor CXCR4 and ligand CXCL12 were detected in tissue specimens from 20 cases of primary cancer focus and lymphogenous metastasis of salivary adenoid cystic carcinoma, of which 7 cases were associated with lung metastasis and 3 with lympogenons metastasis. Twenty cases of tongue carcinoma (including 10 cases with lymphogenous metastasis) and 15 cases of mucoepidermoid carcinoma (including 5 cases with lymphogenous metastasis) were used as the malignant control group; and salivary mixed tumor ( n =10), tongue leukoceratosis ( n = 10) and cervical lymph node reactive hyperplasia ( n = 10) were used as the benign control group. Results: Expression of CXCR4 in the tissues and lymph metastases of oral and maxillofacial salivary ACC, mucoepidermoid carcinoma and tongue carcinoma was significantly higher than that of the benign control group ( P < 0.05); expression of CXCR4 in the primary focus of ACC was significantly higher than that of the malignant control group; and expression of CXCR4 in the ACC with lung metastasis was 87.1% (6/7), significantly higher than that without lung metastasis( P <0.01 ). There was evident positive expression of CXCL12 in endotheliocytes of microvessels within cancer and paracancer tissues and significantly high expression of CXCL12 in lymphogenous metastasis( P < 0.05). Conclusion: Chemokine receptor CXCR4 and its ligand CXCL12 may be associated with local invasion and lymphogenous metastasis of oral and maxillofacial cancer, especially with lung metastasis of salivary ACC.

  10. RTN3 Regulates the Expression Level of Chemokine Receptor CXCR4 and is Required for Migration of Primordial Germ Cells

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    Haitao Li

    2016-04-01

    Full Text Available CXCR4 is a crucial chemokine receptor that plays key roles in primordial germ cell (PGC homing. To further characterize the CXCR4-mediated migration of PGCs, we screened CXCR4-interacting proteins using yeast two-hybrid screening. We identified reticulon3 (RTN3, a member of the reticulon family, and considered an apoptotic signal transducer, as able to interact directly with CXCR4. Furthermore, we discovered that the mRNA and protein expression levels of CXCR4 could be regulated by RTN3. We also found that RTN3 altered CXCR4 translocation and localization. Moreover, increasing the signaling of either CXCR4b or RTN3 produced similar PGC mislocalization phenotypes in zebrafish. These results suggested that RTN3 modulates PGC migration through interaction with, and regulation of, CXCR4.

  11. Expression of the chemokine receptor CXCR4 on lymphocytes of leprosy patients

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    V.A. Mendonça

    2011-12-01

    Full Text Available Leprosy is caused by Mycobacterium leprae, which induces chronic granulomatous infection of the skin and peripheral nerves. The disease ranges from the tuberculoid to the lepromatous forms, depending on the cellular immune response of the host. Chemokines are thought to be involved in the immunopathogenesis of leprosy, but few studies have investigated the expression of chemokine receptors on leukocytes of leprosy patients. In the present study, we evaluated 21 leprosy patients (M/F: 16/5 with a new diagnosis from the Dermatology Outpatient Clinic of the University Hospital, Federal University of Minas Gerais. The control group was composed of 20 healthy members (M/F: 15/5 of the community recruited by means of announcements. The expression of CCR2, CCR3, CCR5, and CXCR4 was investigated by flow cytometry on the surface of peripheral blood lymphocytes. There was a decrease in percentage of CD3+CXCR4+ and CD4+CXCR4+ lymphocytes in the peripheral blood of leprosy patients (median [range], 17.6 [2.7-41.9] and 65.3 [3.9-91.9], respectively compared to the control group (median [range], 43.0 [3.7-61.3] and 77.2 [43.6-93.5], respectively. The percentage of CD4+CXCR4+ was significantly lower in patients with the tuberculoid form (median [range], 45.7 [0.0-83.1] of the disease, but not in lepromatous patients (median [range], 81.5 [44.9-91.9]. The CXCR4 chemokine receptor may play a role in leprosy immunopathogenesis, probably directing cell migration to tissue lesions in tuberculoid leprosy patients.

  12. Expression and functional heterogeneity of chemokine receptors CXCR4 and CXCR7 in primary patient-derived glioblastoma cells.

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    Che Liu

    Full Text Available Glioblastoma (GBM is the most common primary brain tumor in adults. The poor prognosis and minimally successful treatments of these tumors indicates a need to identify new therapeutic targets. Therapy resistance of GBMs is attributed to heterogeneity of the glioblastoma due to genetic alterations and functional subpopulations. Chemokine receptors CXCR4 and CXCR7 play important roles in progression of various cancers although the specific functions of the CXCL12-CXCR4-CXCR7 axis in GBM are less characterized. In this study we examined the expression and function of CXCR4 and CXCR7 in four primary patient-derived GBM cell lines of the proliferative subclass, investigating their roles in in vitro growth, migration, sphere and tube formation. CXCR4 and CXCR7 cell surface expression was heterogeneous both between and within each cell line examined, which was not reflected by RT-PCR analysis. Variable percentages of CXCR4+CXCR7- (CXCR4 single positive, CXCR4-CXCR7+ (CXCR7 single positive, CXCR4+CXCR7+ (double positive, and CXCR4-CXCR7- (double negative subpopulations were evident across the lines examined. A subpopulation of slow cell cycling cells was enriched in CXCR4 and CXCR7. CXCR4+, CXCR7+, and CXCR4+/CXCR7+ subpopulations were able to initiate intracranial tumors in vivo. CXCL12 stimulated in vitro cell growth, migration, sphere formation and tube formation in some lines and, depending on the response, the effects were mediated by either CXCR4 or CXCR7. Collectively, our results indicate a high level of heterogeneity in both the surface expression and functions of CXCR4 and CXCR7 in primary human GBM cells of the proliferative subclass. Should targeting of CXCR4 and CXCR7 provide clinical benefits to GBM patients, a personalized treatment approach should be considered given the differential expression and functions of these receptors in GBM.

  13. Fluorescence resonance energy transfer imaging reveals that chemokine-binding modulates heterodimers of CXCR4 and CCR5 receptors.

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    Nilgun Isik

    Full Text Available BACKGROUND: Dimerization has emerged as an important feature of chemokine G-protein-coupled receptors. CXCR4 and CCR5 regulate leukocyte chemotaxis and also serve as a co-receptor for HIV entry. Both receptors are recruited to the immunological synapse during T-cell activation. However, it is not clear whether they form heterodimers and whether ligand binding modulates the dimer formation. METHODOLOGY/PRINCIPAL FINDINGS: Using a sensitive Fluorescence Resonance Energy Transfer (FRET imaging method, we investigated the formation of CCR5 and CXCR4 heterodimers on the plasma membrane of live cells. We found that CCR5 and CXCR4 exist as constitutive heterodimers and ligands of CCR5 and CXCR4 promote different conformational changes within these preexisting heterodimers. Ligands of CCR5, in contrast to a ligand of CXCR4, induced a clear increase in FRET efficiency, indicating that selective ligands promote and stabilize a distinct conformation of the heterodimers. We also found that mutations at C-terminus of CCR5 reduced its ability to form heterodimers with CXCR4. In addition, ligands induce different conformational transitions of heterodimers of CXCR4 and CCR5 or CCR5(STA and CCR5(Delta4. CONCLUSIONS/SIGNIFICANCE: Taken together, our data suggest a model in which CXCR4 and CCR5 spontaneously form heterodimers and ligand-binding to CXCR4 or CCR5 causes different conformational changes affecting heterodimerization, indicating the complexity of regulation of dimerization/function of these chemokine receptors by ligand binding.

  14. Baclofen and other GABAB receptor agents are allosteric modulators of the CXCL12 chemokine receptor CXCR4.

    Science.gov (United States)

    Guyon, Alice; Kussrow, Amanda; Olmsted, Ian Roys; Sandoz, Guillaume; Bornhop, Darryl J; Nahon, Jean-Louis

    2013-07-10

    CXCR4, a receptor for the chemokine CXCL12 (stromal-cell derived factor-1α), is a G-protein-coupled receptor (GPCR), expressed in the immune and CNS and integrally involved in various neurological disorders. The GABAB receptor is also a GPCR that mediates metabotropic action of the inhibitory neurotransmitter GABA and is located on neurons and immune cells as well. Using diverse approaches, we report novel interaction between GABAB receptor agents and CXCR4 and demonstrate allosteric binding of these agents to CXCR4. First, both GABAB antagonists and agonists block CXCL12-elicited chemotaxis in human breast cancer cells. Second, a GABAB antagonist blocks the potentiation by CXCL12 of high-threshold Ca(2+) channels in rat neurons. Third, electrophysiology in Xenopus oocytes and human embryonic kidney cell line 293 cells in which we coexpressed rat CXCR4 and the G-protein inward rectifier K(+) (GIRK) channel showed that GABAB antagonist and agonist modified CXCL12-evoked activation of GIRK channels. To investigate whether GABAB ligands bind to CXCR4, we expressed this receptor in heterologous systems lacking GABAB receptors and performed competition binding experiments. Our fluorescent resonance energy transfer experiments suggest that GABAB ligands do not bind CXCR4 at the CXCL12 binding pocket suggesting allosteric modulation, in accordance with our electrophysiology experiments. Finally, using backscattering interferometry and lipoparticles containing only the CXCR4 receptor, we quantified the binding affinity for the GABAB ligands, confirming a direct interaction with the CXCR4 receptor. The effect of GABAergic agents on CXCR4 suggests new therapeutic potentials for neurological and immune diseases.

  15. Roles of Chemokine Receptor 4(CXCR4)and Chemokine Ligand 12(CXCL12)in Metastasis of Hepatocellular Carcinoma Cells

    Institute of Scientific and Technical Information of China (English)

    Hui Liu; Zeya Pan; Aijun Li; Siyuan Fu; Yin Lei; Hangyong Sun; Mengchao Wu; Weiping Zhou

    2008-01-01

    Chemokines are involved in human hepatocellular carcinoma (HCC) carcinogenesis.However,the exact mechanism of chemokines in HCC carcinogenesis remains unknown.Here we investigated the roles of chemokine receptor 4(CXCR4) and chemokine ligand 12(CXCL12)in the metastasis of HCC.We found that the expression levels of CXCR4 mRNA in HCC tissues,MHCC97 cells,and HUVEC cells were 2.52±1.13,2.34±1.16 and 1.63±1.26,respectively and that the CXCR4 protein levels were 1.38±0.13,1.96±0.32 and 1.86±0.21,respectively.In contrast,CXCR4 was not detected in normal hepatic tissues.In 78 HCC patients,we also found that the concentration of CXCL12 in cancerous ascitic fluid was 783-8,364 Pg/ml and that CXCL12 mRNA level in HCC metastasis portal lymph nodes was 1.21±0.87 but undetectable in normal hepatic tissues.Finally we discovered that recombinant human CXCL12 could induce MHCC97 cells and HUVEC cells to migrate with chemotactic indexes(CI)of 3.9±1.1 and 4.1±1.6,respectively.Cancerous ascitic fluid could also induce the migration of MHCC97 cells with a CI of 1.9±0.8.Thus,our data suggest that CXCR4 and CXCL12 may play an important role in the metastasis of HCC by promoting the migration of tumor cells.

  16. Effect of chemokine receptor CXCR4 on hypoxia-induced pulmonary hypertension and vascular remodeling in rats

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    Hales Charles A

    2011-02-01

    Full Text Available Abstract Background CXCR4 is the receptor for chemokine CXCL12 and reportedly plays an important role in systemic vascular repair and remodeling, but the role of CXCR4 in development of pulmonary hypertension and vascular remodeling has not been fully understood. Methods In this study we investigated the role of CXCR4 in the development of pulmonary hypertension and vascular remodeling by using a CXCR4 inhibitor AMD3100 and by electroporation of CXCR4 shRNA into bone marrow cells and then transplantation of the bone marrow cells into rats. Results We found that the CXCR4 inhibitor significantly decreased chronic hypoxia-induced pulmonary hypertension and vascular remodeling in rats and, most importantly, we found that the rats that were transplanted with the bone marrow cells electroporated with CXCR4 shRNA had significantly lower mean pulmonary pressure (mPAP, ratio of right ventricular weight to left ventricular plus septal weight (RV/(LV+S and wall thickness of pulmonary artery induced by chronic hypoxia as compared with control rats. Conclusions The hypothesis that CXCR4 is critical in hypoxic pulmonary hypertension in rats has been demonstrated. The present study not only has shown an inhibitory effect caused by systemic inhibition of CXCR4 activity on pulmonary hypertension, but more importantly also has revealed that specific inhibition of the CXCR4 in bone marrow cells can reduce pulmonary hypertension and vascular remodeling via decreasing bone marrow derived cell recruitment to the lung in hypoxia. This study suggests a novel therapeutic approach for pulmonary hypertension by inhibiting bone marrow derived cell recruitment.

  17. Genetic characterization of the chemokine receptor CXCR4 gene in lagomorphs: comparison between the families Ochotonidae and Leporidae.

    Science.gov (United States)

    Abrantes, J; Esteves, P J; Carmo, C R; Müller, A; Thompson, G; van der Loo, W

    2008-04-01

    Chemokines receptors are transmembrane proteins that bind chemokines. Chemokines and their receptors are known to play a crucial role in the immune system and in pathogen entry. There is evidence that myxoma virus, the causative agent of myxomatosis, can use the chemokine receptor CXCR4 to infect cells. This virus causes a benign disease in its natural host, Sylvilagus, but in the European rabbit (Oryctolagus cuniculus) it causes a highly fatal and infectious disease known as myxomatosis. We have characterized the chemokine receptor CXCR4 gene in five genera of the order Lagomorpha, Ochotona (Ochotonidae), and Oryctolagus, Lepus, Bunolagus and Sylvilagus (Leporidae). In lagomorphs, the CXCR4 is highly conserved, with most of the protein diversity found at surface regions. Five amino acid replacements were observed, two in the intracellular loops, one in the transmembrane domain and two in the extracellular loops. Oryctolagus features unique amino acid changes at the intracellular domains, putting this genus apart of all other lagomorphs. Furthermore, in the 37 European rabbits analysed, which included healthy rabbits and rabbits with clinical symptoms of myxomatosis, 14 nucleotide substitutions were obtained but no amino acid differences were observed.

  18. Fluorescence Resonance Energy Transfer Imaging Reveals that Chemokine-Binding Modulates Heterodimers of CXCR4 and CCR5 Receptors

    OpenAIRE

    2008-01-01

    BACKGROUND: Dimerization has emerged as an important feature of chemokine G-protein-coupled receptors. CXCR4 and CCR5 regulate leukocyte chemotaxis and also serve as a co-receptor for HIV entry. Both receptors are recruited to the immunological synapse during T-cell activation. However, it is not clear whether they form heterodimers and whether ligand binding modulates the dimer formation. METHODOLOGY/PRINCIPAL FINDINGS: Using a sensitive Fluorescence Resonance Energy Transfer (FRET) imaging ...

  19. Simultaneous Activation of Induced Heterodimerization between CXCR4 Chemokine Receptor and Cannabinoid Receptor 2 (CB2) Reveals a Mechanism for Regulation of Tumor Progression.

    Science.gov (United States)

    Coke, Christopher J; Scarlett, Kisha A; Chetram, Mahandranauth A; Jones, Kia J; Sandifer, Brittney J; Davis, Ahriea S; Marcus, Adam I; Hinton, Cimona V

    2016-05-06

    The G-protein-coupled chemokine receptor CXCR4 generates signals that lead to cell migration, cell proliferation, and other survival mechanisms that result in the metastatic spread of primary tumor cells to distal organs. Numerous studies have demonstrated that CXCR4 can form homodimers or can heterodimerize with other G-protein-coupled receptors to form receptor complexes that can amplify or decrease the signaling capacity of each individual receptor. Using biophysical and biochemical approaches, we found that CXCR4 can form an induced heterodimer with cannabinoid receptor 2 (CB2) in human breast and prostate cancer cells. Simultaneous, agonist-dependent activation of CXCR4 and CB2 resulted in reduced CXCR4-mediated expression of phosphorylated ERK1/2 and ultimately reduced cancer cell functions such as calcium mobilization and cellular chemotaxis. Given that treatment with cannabinoids has been shown to reduce invasiveness of cancer cells as well as CXCR4-mediated migration of immune cells, it is plausible that CXCR4 signaling can be silenced through a physical heterodimeric association with CB2, thereby inhibiting subsequent functions of CXCR4. Taken together, the data illustrate a mechanism by which the cannabinoid system can negatively modulate CXCR4 receptor function and perhaps tumor progression.

  20. The chemokine CXCL12 and its receptor CXCR4 are implicated in human seminoma metastasis.

    Science.gov (United States)

    McIver, S C; Loveland, K L; Roman, S D; Nixon, B; Kitazawa, R; McLaughlin, E A

    2013-05-01

    Seminoma and non-seminoma tumours increasingly occur within the western population. These tumours originate from carcinoma in situ (CIS) cells, which arise from dysfunctional gonocytes. CXCL12 and its receptors, CXCR4 and CXCR7, have been implicated in migration, proliferation and survival of gonocytes and their precursors and progeny, primordial germ cells and spermatogonial stem cells respectively. We previously found evidence that several miRNA molecules predicted to modulate CXCR4 signalling are differentially expressed during the differentiation of gonocytes into spermatogonia in mice. Bioinformatic analysis predicted these miRNA to modulate CXCR4 signalling, leading us to hypothesize that CXCL12-mediated CXCR4 signalling is involved in the disrupted differentiation of gonocytes that underpins CIS formation. Indeed, we detected CXCL12 in Sertoli cells of normal human testis, and relatively high expression in tumour stroma with concomitant weak staining in dispersed tumour cells. In contrast, CXCR4 was expressed in spermatogonial and meiotic germ cells of normal testis and in the majority of tumour cells. Quantitative RT-PCR identified elevated CXCR4 transcript levels in seminoma compared with normal testis and to non-seminoma, potentially reflecting the higher proportion of dysfunctional germ cells within seminomas. In the normal testis, expression of CXCR4 downstream signalling molecules phospho-MEK1/2 and phospho-ERK1/2 correlated with CXCR4/CXCL12 expression. Strikingly, this correlation was absent in seminoma and non-seminoma samples, suggesting that CXCL12 signalling is disrupted. Proliferation rate and cell survival were not altered by CXCL12 in either seminoma (TCam-2) or non-seminoma (833ke) cell lines. However, CXCL12 exposure induced TCam-2 cell invasion though simulated basement membrane, while in contrast, we provide the novel evidence that CXCR4-expressing non-seminoma cell lines 833ke and NTera2/D1 do not invade in response to CXCL12. These

  1. Cloning of Encoding Sequences for Chemokine Receptors CXCR4 and CCR5 from a Chinese Lymphocyte cDNAs

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    @@ It has been known recently that cofactors, which belong to the family of seven-transmembrane GTP-binding protein-coupled receptors, are necessary for the entry of HIV-1 into CD4+cells. The CXC chemokine receptor 4(CXCR4) was first found to act as the coreceptor for the infection of T cell line-tropic HIV-1 strains to T helper cells in 1996. Keeping in step with this find the CC chemokine receptor 5(CCR5)was also identified as a coreceptor for macrophage-tropic virus. Both of the coreceptors could be used in basic research and application design for AIDS.

  2. Shared usage of the chemokine receptor CXCR4 by primary and laboratory-adapted strains of feline immunodeficiency virus.

    Science.gov (United States)

    Richardson, J; Pancino, G; Merat, R; Leste-Lasserre, T; Moraillon, A; Schneider-Mergener, J; Alizon, M; Sonigo, P; Heveker, N

    1999-05-01

    Strains of the feline immunodeficiency virus (FIV) presently under investigation exhibit distinct patterns of in vitro tropism. In particular, the adaptation of FIV for propagation in Crandell feline kidney (CrFK) cells results in the selection of strains capable of forming syncytia with cell lines of diverse species origin. The infection of CrFK cells by CrFK-adapted strains appears to require the chemokine receptor CXCR4 and is inhibited by its natural ligand, stromal cell-derived factor 1alpha (SDF-1alpha). Here we found that inhibitors of CXCR4-mediated infection by human immunodeficiency virus type I (HIV-1), such as the bicyclam AMD3100 and short peptides derived from the amino-terminal region of SDF-1alpha, also blocked infection of CrFK by FIV. Nevertheless, we observed differences in the ranking order of the peptides as inhibitors of FIV and HIV-1 and showed that such differences are related to the species origin of CXCR4 and not that of the viral envelope. These results suggest that, although the envelope glycoproteins of FIV and HIV-1 are substantially divergent, FIV and HIV-1 interact with CXCR4 in a highly similar manner. We have also addressed the role of CXCR4 in the life cycle of primary isolates of FIV. Various CXCR4 ligands inhibited infection of feline peripheral blood mononuclear cells (PBMC) by primary FIV isolates in a concentration-dependent manner. These ligands also blocked the viral transduction of feline PBMC by pseudotyped viral particles when infection was mediated by the envelope glycoprotein of a primary FIV isolate but not by the G protein of vesicular stomatitis virus, indicating that they act at an envelope-mediated step and presumably at viral entry. These findings strongly suggest that primary and CrFK-adapted strains of FIV, despite disparate in vitro tropisms, share usage of CXCR4.

  3. i-bodies, Human Single Domain Antibodies That Antagonize Chemokine Receptor CXCR4.

    Science.gov (United States)

    Griffiths, Katherine; Dolezal, Olan; Cao, Benjamin; Nilsson, Susan K; See, Heng B; Pfleger, Kevin D G; Roche, Michael; Gorry, Paul R; Pow, Andrew; Viduka, Katerina; Lim, Kevin; Lu, Bernadine G C; Chang, Denison H C; Murray-Rust, Thomas; Kvansakul, Marc; Perugini, Matthew A; Dogovski, Con; Doerflinger, Marcel; Zhang, Yuan; Parisi, Kathy; Casey, Joanne L; Nuttall, Stewart D; Foley, Michael

    2016-06-10

    CXCR4 is a G protein-coupled receptor with excellent potential as a therapeutic target for a range of clinical conditions, including stem cell mobilization, cancer prognosis and treatment, fibrosis therapy, and HIV infection. We report here the development of a fully human single-domain antibody-like scaffold termed an "i-body," the engineering of which produces an i-body library possessing a long complementarity determining region binding loop, and the isolation and characterization of a panel of i-bodies with activity against human CXCR4. The CXCR4-specific i-bodies show antagonistic activity in a range of in vitro and in vivo assays, including inhibition of HIV infection, cell migration, and leukocyte recruitment but, importantly, not the mobilization of hematopoietic stem cells. Epitope mapping of the three CXCR4 i-bodies AM3-114, AM4-272, and AM3-523 revealed binding deep in the binding pocket of the receptor.

  4. 趋化因子SDF-1与受体CXCR4的研究进展%The research progress in the chemokine SDF-1 and the chemokine receptor CXCR4

    Institute of Scientific and Technical Information of China (English)

    杨志峰; 杨清玲; 陈昌杰

    2011-01-01

    趋化因子SDF-1(stromal cell-derived factor-1)与其受体CXCR4( CXC chemokine receptor 4 )分别属于CXC类趋化因子和CXCR类G蛋白偶联受体超家族.功能研究表明,SDF-1/CXCR4轴在机体的免疫、炎症、胚胎发育、器官发生、肿瘤、HIV病、WHIM综合征等多种生物学过程中发挥着重要的作用,已成为当今生物学研究的热点之一.本文对SDF-1及CXCR4的结构、信号转导、生物学意义就当前研究的进展情况进行了综述.

  5. Expression of chemokine CXCL12 and its receptor CXCR4 in folliculostellate (FS) cells of the rat anterior pituitary gland: the CXCL12/CXCR4 axis induces interconnection of FS cells.

    Science.gov (United States)

    Horiguchi, Kotaro; Ilmiawati, Cimi; Fujiwara, Ken; Tsukada, Takehiro; Kikuchi, Motoshi; Yashiro, Takashi

    2012-04-01

    The anterior pituitary gland is composed of five types of hormone-producing cells plus folliculostellate (FS) cells, which do not produce classical anterior pituitary hormones. FS cells are interconnected by cytoplasmic processes and encircle hormone-producing cells or aggregate homophilically. Using living-cell imaging of primary culture, we recently reported that some FS cells precisely extend their cytoplasmic processes toward other FS cells and form interconnections with them. These phenomena suggest the presence of a chemoattractant factor that facilitates the interconnection. In this study, we attempted to discover the factor that induces interconnection of FS cells and succeeded in identifying chemokine (CXC)-L12 and its receptor CXCR4 as potential candidate molecules. CXCL12 is a chemokine of the CXC subfamily. It exerts its effects via CXCR4, a G protein-coupled receptor. The CXCL12/CXCR4 axis is a potent chemoattractant for many types of neural cells. First, we revealed that CXCL12 and CXCR4 are expressed by FS cells in rat anterior pituitary gland. Next, to clarify the function of the CXCL12/CXCR4 axis in FS cells, we observed living anterior pituitary cells in primary culture with specific CXCL12 inhibitor or CXCR4 antagonist and noted that extension of cytoplasmic processes and interconnection of FS cells were inhibited. Finally, we examined FS cell migration and invasion by using Matrigel matrix assays. CXCL12 treatment resulted in markedly increased FS cell migration and invasion. These data suggest that FS cells express chemokine CXCL12 and its receptor CXCR4 and that the CXCL12/CXCR4 axis evokes interconnection of FS cells.

  6. CXC chemokine CXCL12 and its receptor CXCR4 in tree shrews (Tupaia belangeri): structure, expression and function.

    Science.gov (United States)

    Chen, Guiyuan; Wang, Wei; Meng, Shengke; Zhang, Lichao; Wang, Wenxue; Jiang, Zongmin; Yu, Min; Cui, Qinghua; Li, Meizhang

    2014-01-01

    Chemokines are small secreted proteins functionally involved in the immune system's regulation of lymphocyte migration across numerous mammalian species. Given its growing popularity in immunological models, we investigated the structure and function of chemokine CXCL12 protein in tree shrews. We found that CXCL12 and its receptor CXCR4 in tree shrew had structural similarities to their homologous human proteins. Phylogenetic analysis supports the view that tree shrew is evolutionarily-close to the primates. Our results also showed that the human recombinant CXCL12 protein directly enhanced the migration of tree shrew's lymphocytes in vitro, while AMD3100 enhanced the mobilization of hematopoietic progenitor cells (HPCs) from bone marrow into peripheral blood in tree shrew in vivo. Collectively, these findings suggested that chemokines in tree shrews may play the same or similar roles as those in humans, and that the tree shrew is a viable animal model for studying human immunological diseases.

  7. CXC chemokine CXCL12 and its receptor CXCR4 in tree shrews (Tupaia belangeri: structure, expression and function.

    Directory of Open Access Journals (Sweden)

    Guiyuan Chen

    Full Text Available Chemokines are small secreted proteins functionally involved in the immune system's regulation of lymphocyte migration across numerous mammalian species. Given its growing popularity in immunological models, we investigated the structure and function of chemokine CXCL12 protein in tree shrews. We found that CXCL12 and its receptor CXCR4 in tree shrew had structural similarities to their homologous human proteins. Phylogenetic analysis supports the view that tree shrew is evolutionarily-close to the primates. Our results also showed that the human recombinant CXCL12 protein directly enhanced the migration of tree shrew's lymphocytes in vitro, while AMD3100 enhanced the mobilization of hematopoietic progenitor cells (HPCs from bone marrow into peripheral blood in tree shrew in vivo. Collectively, these findings suggested that chemokines in tree shrews may play the same or similar roles as those in humans, and that the tree shrew is a viable animal model for studying human immunological diseases.

  8. Expressions and Significance of CXCR4 and CCR7 Chemokine Receptor in Lung Cancer%CCR7、CXCR4在肺癌中的表达及意义

    Institute of Scientific and Technical Information of China (English)

    王述波; 周华; 李作涛; 曹望凯; 韩其正

    2012-01-01

    目的 探讨CC族趋化因子受体7(CCR7)和CXC族趋化因子受体4(CXCR4)在肺癌组织中的表达及临床意义.方法 采用免疫组织化学检测72例肺癌组织标本和30例良性肺疾病肺组织标本中CXCR4和CCR7的表达情况,并分析其不同临床病理特征中表达的差异.结果 CCR7和CXCR4在肺癌组织中的表达阳性率均明显高于正常肺组织,差异有统计学意义(P<0.01);CCR7和CXCR4表达与肺癌患者的TNM分期,纵膈淋巴结转移密切相关(P<0.01),与年龄、性别、病例组织学类型等均无关(P>0.05),并且Spearman相关分析显示,CXCR4表达与CCR7表达呈高度正相关(r =0.623,P<0.001).结论 CXCR4和CCR7在肺癌纵膈淋巴转移中发挥重要作用.%Objective To explore the expression of the CC chemokine receptor-7 ( CCR7 ) and CXC chemokine receptor-4 (CXCR4) in lung cancer and its significance. Methods By using immunohistochemistry technique, the expression of CXCR4 and CCR7 in the cancer specimens of 72 patients with lung cancer and 30 samples of lung tissue from benign pulmonary disease were detected,and analyzed its different clinical and pathological features of expression differences. Results The express positive rate of CCR7 and CXCR4 in the observation group were significantly higher than that in the control group,the difference was statistically significant (P 0. 05). The Spearman rank correlation showed that CXCR4 expression and CCR7 expression were highly correlated(r =0.623 ,P <0.001). Conclusion The abnormal expression of CXCR4 and CCR7 play an important role in the diaphragmatic metastases of lung cancer

  9. Chemokine stromal cell-derived factor 1alpha activates basophils by means of CXCR4

    DEFF Research Database (Denmark)

    Jinquan, T; Jacobi, H H; Jing, C

    2000-01-01

    The CXC chemokine receptor 4 (CXCR4) is predominantly expressed on inactivated naive T lymphocytes, B lymphocytes, dendritic cells, and endothelial cells. CXC chemokine stromal cell-derived factor 1alpha (SDF-1alpha) is the only known ligand for CXCR4. To date, the CXCR4 expression and function...... of SDF-1alpha in basophils are unknown....

  10. Chemokine receptor CCR7 expression predicts poor outcome in uveal melanoma and relates to liver metastasis whereas expression of CXCR4 is not of clinical relevance

    NARCIS (Netherlands)

    T. van den Bosch (Thomas); A.E. Koopmans (Anna); J. Vaarwater (Jolanda); M.M.P. van den Berg (Mike M P); J.E.M.M. de Klein (Annelies); R.M. Verdijk (Robert)

    2013-01-01

    textabstractPurpose. To examine the prognostic relevance of expression of the chemokine receptors CCR7 and CXCR4 and its ligand CXCL12 in uveal melanoma in nonmetastatic and metastatic patients with correlation to liver metastasis and overall survival. Methods. Primary uveal melanoma specimens from

  11. CXC Chemokine Receptor 7 (CXCR7) Regulates CXCR4 Protein Expression and Capillary Tuft Development in Mouse Kidney

    Science.gov (United States)

    Haege, Sammy; Mueller, Wiebke; Nietzsche, Sandor; Lupp, Amelie; Mackay, Fabienne; Schulz, Stefan; Stumm, Ralf

    2012-01-01

    Background The CXCL12/CXCR4 axis is involved in kidney development by regulating formation of the glomerular tuft. Recently, a second CXCL12 receptor was identified and designated CXCR7. Although it is established that CXCR7 regulates heart and brain development in conjunction with CXCL12 and CXCR4, little is known about the influence of CXCR7 on CXCL12 dependent kidney development. Methodology/Principal Findings We provided analysis of CXCR7 expression and function in the developing mouse kidney. Using in situ hybridization, we identified CXCR7 mRNA in epithelial cells including podocytes at all nephron stages up to the mature glomerulus. CXCL12 mRNA showed a striking overlap with CXCR7 mRNA in epithelial structures. In addition, CXCL12 was detected in stromal cells and the glomerular tuft. Expression of CXCR4 was complementary to that of CXCR7 as it occurred in mesenchymal cells, outgrowing ureteric buds and glomerular endothelial cells but not in podocytes. Kidney examination in CXCR7 null mice revealed ballooning of glomerular capillaries as described earlier for CXCR4 null mice. Moreover, we detected a severe reduction of CXCR4 protein but not CXCR4 mRNA within the glomerular tuft and in the condensed mesenchyme. Malformation of the glomerular tuft in CXCR7 null mice was associated with mesangial cell clumping. Conclusions/Significance We established that there is a similar glomerular pathology in CXCR7 and CXCR4 null embryos. Based on the phenotype and the anatomical organization of the CXCL12/CXCR4/CXCR7 system in the forming glomerulus, we propose that CXCR7 fine-tunes CXCL12/CXCR4 mediated signalling between podocytes and glomerular capillaries. PMID:22880115

  12. [68Ga]Pentixafor-PET/CT for imaging of chemokine receptor CXCR4 expression in multiple myeloma - Comparison to [18F]FDG and laboratory values

    Science.gov (United States)

    Lapa, Constantin; Schreder, Martin; Schirbel, Andreas; Samnick, Samuel; Kortüm, Klaus Martin; Herrmann, Ken; Kropf, Saskia; Einsele, Herrmann; Buck, Andreas K.; Wester, Hans-Jürgen; Knop, Stefan; Lückerath, Katharina

    2017-01-01

    Chemokine (C-X-C motif) receptor 4 (CXCR4) is a key factor for tumor growth and metastasis in several types of human cancer including multiple myeloma (MM). Proof-of-concept of CXCR4-directed radionuclide therapy in MM has recently been reported. This study assessed the diagnostic performance of the CXCR4-directed radiotracer [68Ga]Pentixafor in MM and a potential role for stratifying patients to CXCR4-directed therapies. Thirty-five patients with MM underwent [68Ga]Pentixafor-PET/CT for evaluation of eligibility for endoradiotherapy. In 19/35 cases, [18F]FDG-PET/CT for correlation was available. Scans were compared on a patient and on a lesion basis. Tracer uptake was correlated with standard clinical parameters of disease activity. [68Ga]Pentixafor-PET detected CXCR4-positive disease in 23/35 subjects (66%). CXCR4-positivity at PET was independent from myeloma subtypes, cytogenetics or any serological parameters and turned out as a negative prognostic factor. In the 19 patients in whom a comparison to [18F]FDG was available, [68Ga]Pentixafor-PET detected more lesions in 4/19 (21%) subjects, [18F]FDG proved superior in 7/19 (37%). In the remaining 8/19 (42%) patients, both tracers detected an equal number of lesions. [18F]FDG-PET positivity correlated with [68Ga]Pentixafor-PET positivity (p=0.018). [68Ga]Pentixafor-PET provides further evidence that CXCR4 expression frequently occurs in advanced multiple myeloma, representing a negative prognostic factor and a potential target for myeloma specific treatment. However, selecting patients for CXCR4 directed therapies and prognostic stratification seem to be more relevant clinical applications for this novel imaging modality, rather than diagnostic imaging of myeloma. PMID:28042328

  13. Expression of the chemokine receptor CXCR7 in CXCR4-expressing human 143B osteosarcoma cells enhances lung metastasis of intratibial xenografts in SCID mice.

    Science.gov (United States)

    Brennecke, Patrick; Arlt, Matthias J E; Muff, Roman; Campanile, Carmen; Gvozdenovic, Ana; Husmann, Knut; Holzwarth, Nathalie; Cameroni, Elisabetta; Ehrensperger, Felix; Thelen, Marcus; Born, Walter; Fuchs, Bruno

    2013-01-01

    More effective treatment of metastasizing osteosarcoma with a current mean 5-year survival rate of less than 20% requires more detailed knowledge on mechanisms and key regulatory molecules of the complex metastatic process. CXCR4, the receptor of the chemokine CXCL12, has been reported to promote tumor progression and metastasis in osteosarcoma. CXCR7 is a recently deorphanized CXCL12-scavenging receptor with so far not well-defined functions in tumor biology. The present study focused on a potential malignancy enhancing function of CXCR7 in interaction with CXCR4 in osteosarcoma, which was investigated in an intratibial osteosarcoma model in SCID mice, making use of the human 143B osteosarcoma cell line that spontaneously metastasizes to the lung and expresses endogenous CXCR4. 143B osteosarcoma cells stably expressing LacZ (143B-LacZ cells) were retrovirally transduced with a gene encoding HA-tagged CXCR7 (143B-LacZ-X7-HA cells). 143B-LacZ-X7-HA cells co-expressing CXCR7 and CXCR4 exhibited CXCL12 scavenging and enhanced adhesion to IL-1β-activated HUVEC cells compared to 143B-LacZ cells expressing CXCR4 alone. SCID mice intratibially injected with 143B-LacZ-X7-HA cells had significantly (plung metastases than mice injected with 143B-LacZ cells. Unexpectedly, 143B-LacZ-X7-HA cells, unlike 143B-LacZ cells, also metastasized with high incidence to the auriculum cordis. In conclusion, expression of the CXCL12 scavenging receptor CXCR7 in the CXCR4-expressing human 143B osteosarcoma cell line enhances its metastatic activity in intratibial primary tumors in SCID mice that predominantly metastasize to the lung and thereby closely mimic the human disease. These findings point to CXCR7 as a target, complementary to previously proposed CXCR4, for more effective metastasis-suppressive treatment in osteosarcoma.

  14. Differential estrogen-regulation of CXCL12 chemokine receptors, CXCR4 and CXCR7, contributes to the growth effect of estrogens in breast cancer cells.

    Directory of Open Access Journals (Sweden)

    Antoine Boudot

    Full Text Available CXCR4 and CXCR7 are the two receptors for the chemokine CXCL12, a key mediator of the growth effect of estrogens (E2 in estrogen receptor (ER-positive breast cancers. In this study we examined E2-regulation of the CXCL12 axis components and their involvement in the growth of breast cancer cells. CXCR4 and CXCR7 were differentially regulated by E2 which enhanced the expression of both CXCL12 and CXCR4 but repressed the expression of CXCR7. Formaldehyde-associated isolation of regulatory elements (FAIRE revealed that E2-mediated transcriptional regulation of these genes is linked to the control of the compaction state of chromatin at their promoters. This effect could be accomplished via several distal ER-binding sites in the regions surrounding these genes, all of which are located 20-250 kb from the transcription start site. Furthermore, individual down-regulation of CXCL12, CXCR4 or CXCR7 expression as well as the inhibition of their activity significantly decreases the rate of basal cell growth. In contrast, E2-induced cell growth was differentially affected. Unlike CXCR7, the inhibition of the expression or activity of either CXCL12 or CXCR4 significantly blunted the E2-mediated stimulation of cellular growth. Besides, CXCR7 over-expression increased the basal MCF-7 cell growth rate and decreased the growth effect of E2. These findings indicate that E2 regulation of the CXCL12 signaling axis is important for the E2-mediated growth effect of breast cancer cells. These data also provide support for distinct biological functions of CXCR4 and CXCR7 and suggest that targeting CXCR4 and/or CXCR7 would have distinct molecular effects on ER-positive breast tumors.

  15. 愛滋病毒的輔助受體CCR5和CXCR4%The Role of Chemokine Receptors CCR5 and CXCR4 in HIV-1 Infection

    Institute of Scientific and Technical Information of China (English)

    周燁; 樂影穎; Pablo IRIBARREN; 龔望華; 張廈; 王吉民

    2004-01-01

    化學趨化因子介導白細胞遷移,淋巴器官生成、炎症、過敏、動脈粥樣硬化以及惡性腫瘤生長轉移等多種病理生理過程.這些因子結合位於細胞表面的島苷蛋白耦聯受體,從而促進細胞遊走並活化.近年來,化學趨化因子及其受體受到生物醫學界高度重視,原因之一是有些受體被人類免疫缺陷(愛滋)病毒利用作為侵襲細胞的關鍵性輔助受體.在這些受體中,CXCR4和CCR5分別被噬淋巴細胞病毒株或噬巨噬特異細胞病毒株所識別利用.為此,這些受體的配體由於能夠與病毒競爭受體結合位點,成為人體内天然的抗病毒蛋白.生物醫學界和製藥業也正在研究開發能特異地抑制這些受體的分子作為新一代抗人類免疫缺陷病毒的藥物.%Chemokines are key mediators of a variety of pathophysiological responses, including leukocyte trafficking, lymphoid tissue organogenesis, inflammation, allergy, atherosclerosis and malignancy.Chemokines bind and activate a group of G protein-coupled receptors, which, upon ligand binding, transmit a cascade of signaling events culminating in cell migration and activation. For the past few years, chemokines and their receptors have received particular attention due to the discoveries that some of the chemokine receptors are utilized by human immunodeficiency virus type 1 (HIV-1) as coreceptors for cellular entry. Although a number of chemokine and orphan receptors also exhibit coreceptor activity for different strains of HIV-1, CXCR4 and CCR5 are the two essential coreceptors for T-cell line tropic (X4) and macrophage tropic (R5) viruses, respectively.Consequently, chemokine ligands for CXCR4 or CCR5 are potent host-derived anti-HIV-1 agents based on their competitive receptor binding activity and down-regulation of the viral coreceptors. It is recognized that agents targeting HIV-1 coreceptors may have important therapeutic potential.

  16. Effect of CO2 pneumoperitoneum on the expression of the chemokine receptors CXCR4 and CCR7 in colorectal carcinoma cells in vitro

    Institute of Scientific and Technical Information of China (English)

    YANG Chun-kang; LI Guo-dong; YING Min-gang; XU Ke

    2013-01-01

    Background The ability of pneumoperitoneum in laparoscopic surgery to promote proliferation and metastasis of colorectal cancer has become a focus of research in the field of minimally invasive surgery.The aim of this research was to investigate the effect of CO2 pneumoperitoneum under different pressures and exposed times on the expression of chemokine receptors in colorectal carcinoma cells.Methods We constructed an in vitro pneumoperitoneum model.SW480 colon carcinoma cells were exposed to CO2 pneumoperitoneum under different pressures (6,9,12,and 15 mmHg) for 1,2,and 4 hours.These cells were then cultivated under the same conditions as normal SW480 colon carcinoma cells without CO2 pneumoperitoneum (control group),treated at 37℃,and 5% CO2.The expression of the chemokine receptors CXC receptor 4 (CXCR4) and chemokine C receptor 7 (CCR7) was detected by immunocytochemistry and reverse transcriptase polymerase chain reaction after being cultivated for 0,24,48,and 72 hours.Results Immunocytochemistry showed that CXCR4 expression in SW480 cells was significantly decreased in the 6,9,12,and 15 mmHg CO2 pneumoperitoneum-treated groups for the same exposure times compared with controls (P<0.05).CCR7 expression in SW480 cells was significantly decreased in the 12 and 15 mmHg CO2 pneumoperitoneumtreated groups compared with controls (P <0.05).CXCR4 and CCR7 expression increased up to the level of the control group after 24 and 48 hours (P >0.05).If the CO2 pneumoperitoneum pressure increased,CXCR4 and CCR7 expression decreased at all exposure times.If the CO2 pneumoperitoneum exposure time prolonged,there were no significant differences in CXCR4 and CCR7 expression under the same pressure.Under all exposure times,CXCR4 and CCR7 mRNA expression was significantly decreased in the 6,9,12,and 15 mmHg CO2 pneumoperitoneum-treated groups (P<0.05) compared with controls,and it increased up to the level of controls after being cultivated for 48 hours (P >0.05).If

  17. Expression of the chemokine receptor CXCR7 in CXCR4-expressing human 143B osteosarcoma cells enhances lung metastasis of intratibial xenografts in SCID mice.

    Directory of Open Access Journals (Sweden)

    Patrick Brennecke

    Full Text Available More effective treatment of metastasizing osteosarcoma with a current mean 5-year survival rate of less than 20% requires more detailed knowledge on mechanisms and key regulatory molecules of the complex metastatic process. CXCR4, the receptor of the chemokine CXCL12, has been reported to promote tumor progression and metastasis in osteosarcoma. CXCR7 is a recently deorphanized CXCL12-scavenging receptor with so far not well-defined functions in tumor biology. The present study focused on a potential malignancy enhancing function of CXCR7 in interaction with CXCR4 in osteosarcoma, which was investigated in an intratibial osteosarcoma model in SCID mice, making use of the human 143B osteosarcoma cell line that spontaneously metastasizes to the lung and expresses endogenous CXCR4. 143B osteosarcoma cells stably expressing LacZ (143B-LacZ cells were retrovirally transduced with a gene encoding HA-tagged CXCR7 (143B-LacZ-X7-HA cells. 143B-LacZ-X7-HA cells co-expressing CXCR7 and CXCR4 exhibited CXCL12 scavenging and enhanced adhesion to IL-1β-activated HUVEC cells compared to 143B-LacZ cells expressing CXCR4 alone. SCID mice intratibially injected with 143B-LacZ-X7-HA cells had significantly (p<0.05 smaller primary tumors, but significantly (p<0.05 higher numbers of lung metastases than mice injected with 143B-LacZ cells. Unexpectedly, 143B-LacZ-X7-HA cells, unlike 143B-LacZ cells, also metastasized with high incidence to the auriculum cordis. In conclusion, expression of the CXCL12 scavenging receptor CXCR7 in the CXCR4-expressing human 143B osteosarcoma cell line enhances its metastatic activity in intratibial primary tumors in SCID mice that predominantly metastasize to the lung and thereby closely mimic the human disease. These findings point to CXCR7 as a target, complementary to previously proposed CXCR4, for more effective metastasis-suppressive treatment in osteosarcoma.

  18. Rational design of conformationally constrained cyclopentapeptide antagonists for C-x-C chemokine receptor 4 (CXCR4)

    DEFF Research Database (Denmark)

    Mungalpara, Jignesh; Thiele, Stefanie; Eriksen, Øystein;

    2012-01-01

    In the absence of an experimentally determined binding mode for the cyclopentapeptide CXCR4 antagonists, we have rationally designed conformationally constrained analogues to further probe the small peptide binding pocket of CXCR4. Two different rigidification strategies were employed, both...... resulting in highly potent ligands (9 and 13). The information provided by this cyclopentapeptide ligand series will be very valuable in the development of novel peptidomimetic CXCR4 antagonists....

  19. Molecular mechanism of action of monocyclam versus bicyclam non-peptide antagonists in the CXCR4 chemokine receptor

    DEFF Research Database (Denmark)

    Rosenkilde, Mette M; Gerlach, Lars-Ole; Hatse, Sigrid

    2007-01-01

    higher affinity as determined against (125)I-12G5 monoclonal CXCR4 antibody binding, and a 22-fold higher potency in inhibition of CXCL12-induced signaling through phosphatidylinositol accumulation. Mutational mapping of AMD3465 and a series of analogs of this in a library of 23 mutants covering the main...... in transmembrane (TM)-VI (AspVI:23/Asp(262)) and TM-VII (GluVII:06/Glu(288)). Importantly, AMD3465 has picked up novel interaction sites, for example, His(281) located at the interface of extracellular loop 3 and TM-VII and HisIII:05 (His(113)) in the middle of the binding pocket. It is concluded that the simple N...... ensures the efficacious blocking of the receptor, in a similar manner can be replaced by chemical moieties allowing for, for example, oral bioavailability....

  20. The chemokine receptors CXCR4/CXCR7 and their primary heterodimeric ligands CXCL12 and CXCL12/high mobility group box 1 in pancreatic cancer growth and development: finding flow.

    Science.gov (United States)

    Shakir, Murtaza; Tang, Daolin; Zeh, Herbert J; Tang, Siu Wah; Anderson, Carolyn J; Bahary, Nathan; Lotze, Michael T

    2015-05-01

    Novel therapies need to be developed for patients with pancreatic cancer because of the poor outcomes of current regimens. Pancreatic cancer cells respond to the C-X-C chemokine receptor type 4 (CXCR4)/C-X-C chemokine receptor type 7 (CXCR7)/C-X-C motif chemokine 12 (CXCL12)/high-mobility group box 1 signaling axis and this axis presents a novel target for therapy. C-X-C motif chemokine 12 stimulates CXCR4/CXCR7-bearing cells in a paracrine manner. C-X-C chemokine receptor type 4 and CXCR7 are transmembrane G protein-coupled receptors that, upon interaction with ligand CXCL12, activate downstream protein kinases that promote a more aggressive behavior. C-X-C chemokine receptor type 4 is expressed on most pancreatic cancer cells, whereas CXCR7 is primarily expressed on tumor-associated endothelium. High-mobility group box 1 promotes the CXCR4 and CXCL12 interaction, promoting angiogenesis and lymphangiogenesis. Hypoxia-inducible factor 1 is a potent stimulator of CXCR4 and CXCL12 expression, promoting more aggressive behavior. This receptor/ligand interaction can be disrupted by CXCR4 antagonists available and in clinical use to harvest bone marrow stem cells. Novel imaging strategies are now being developed at several centers to evaluate response to therapy and identify early recurrence. Thus, the CXCR4/CXCR7/CXCL12 interaction plays a critical role in cancer cell progression, proliferation, invasion, as well as metastasis and is a suitable target for therapy, imaging, as well as development of novel diagnostics.

  1. High-level production, solubilization and purification of synthetic human GPCR chemokine receptors CCR5, CCR3, CXCR4 and CX3CR1.

    Directory of Open Access Journals (Sweden)

    Hui Ren

    Full Text Available Chemokine receptors belong to a class of integral membrane G-protein coupled receptors (GPCRs and are responsible for transmitting signals from the extracellular environment. However, the structural changes in the receptor, connecting ligand binding to G-protein activation, remain elusive for most GPCRs due to the difficulty to produce them for structural and functional studies. We here report high-level production in E.coli of 4 human GPCRs, namely chemokine receptors (hCRs CCR5, CCR3, CXCR4 and CX3CR1 that are directly involved in HIV-1 infection, asthma and cancer metastasis. The synthetic genes of CCR5, CCR3, CXCR4 and CX3CR1 were synthesized using a two-step assembly/amplification PCR method and inserted into two different kinds of expression systems. After systematic screening of growth conditions and host strains, TB medium was selected for expression of pEXP-hCRs. The low copy number pBAD-DEST49 plasmid, with a moderately strong promoter tightly regulated by L-arabinose, proved helpful for reducing toxicity of expressed membrane proteins. The synthetic Trx-hCR fusion genes in the pBAD-DEST49 vector were expressed at high levels in the Top10 strain. After a systematic screen of 96 detergents, the zwitterionic detergents of the Fos-choline series (FC9-FC16 emerged as the most effective for isolation of the hCRs. The FC14 was selected both for solubilization from bacterial lysates and for stabilization of the Trx-hCRs during purification. Thus, the FC-14 solubilized Trx-hCRs could be purified using size exclusion chromatography as monomers and dimers with the correct apparent MW and their alpha-helical content determined by circular dichroism. The identity of two of the expressed hCRs (CCR3 and CCR5 was confirmed using immunoblots using specific monoclonal antibodies. After optimization of expression systems and detergent-mediated purification procedures, we achieved large-scale, high-level production of 4 human GPCR chemokine receptor in a

  2. High-level production, solubilization and purification of synthetic human GPCR chemokine receptors CCR5, CCR3, CXCR4 and CX3CR1.

    Science.gov (United States)

    Ren, Hui; Yu, Daoyong; Ge, Baosheng; Cook, Brian; Xu, Zhinan; Zhang, Shuguang

    2009-01-01

    Chemokine receptors belong to a class of integral membrane G-protein coupled receptors (GPCRs) and are responsible for transmitting signals from the extracellular environment. However, the structural changes in the receptor, connecting ligand binding to G-protein activation, remain elusive for most GPCRs due to the difficulty to produce them for structural and functional studies. We here report high-level production in E.coli of 4 human GPCRs, namely chemokine receptors (hCRs) CCR5, CCR3, CXCR4 and CX3CR1 that are directly involved in HIV-1 infection, asthma and cancer metastasis. The synthetic genes of CCR5, CCR3, CXCR4 and CX3CR1 were synthesized using a two-step assembly/amplification PCR method and inserted into two different kinds of expression systems. After systematic screening of growth conditions and host strains, TB medium was selected for expression of pEXP-hCRs. The low copy number pBAD-DEST49 plasmid, with a moderately strong promoter tightly regulated by L-arabinose, proved helpful for reducing toxicity of expressed membrane proteins. The synthetic Trx-hCR fusion genes in the pBAD-DEST49 vector were expressed at high levels in the Top10 strain. After a systematic screen of 96 detergents, the zwitterionic detergents of the Fos-choline series (FC9-FC16) emerged as the most effective for isolation of the hCRs. The FC14 was selected both for solubilization from bacterial lysates and for stabilization of the Trx-hCRs during purification. Thus, the FC-14 solubilized Trx-hCRs could be purified using size exclusion chromatography as monomers and dimers with the correct apparent MW and their alpha-helical content determined by circular dichroism. The identity of two of the expressed hCRs (CCR3 and CCR5) was confirmed using immunoblots using specific monoclonal antibodies. After optimization of expression systems and detergent-mediated purification procedures, we achieved large-scale, high-level production of 4 human GPCR chemokine receptor in a two

  3. High-Level Production, Solubilization and Purification of Synthetic Human GPCR Chemokine Receptors CCR5, CCR3, CXCR4 and CX3CR1

    Science.gov (United States)

    Ren, Hui; Yu, Daoyong; Ge, Baosheng; Cook, Brian; Xu, Zhinan; Zhang, Shuguang

    2009-01-01

    Chemokine receptors belong to a class of integral membrane G-protein coupled receptors (GPCRs) and are responsible for transmitting signals from the extracellular environment. However, the structural changes in the receptor, connecting ligand binding to G-protein activation, remain elusive for most GPCRs due to the difficulty to produce them for structural and functional studies. We here report high-level production in E.coli of 4 human GPCRs, namely chemokine receptors (hCRs) CCR5, CCR3, CXCR4 and CX3CR1 that are directly involved in HIV-1 infection, asthma and cancer metastasis. The synthetic genes of CCR5, CCR3, CXCR4 and CX3CR1 were synthesized using a two-step assembly/amplification PCR method and inserted into two different kinds of expression systems. After systematic screening of growth conditions and host strains, TB medium was selected for expression of pEXP-hCRs. The low copy number pBAD-DEST49 plasmid, with a moderately strong promoter tightly regulated by L-arabinose, proved helpful for reducing toxicity of expressed membrane proteins. The synthetic Trx-hCR fusion genes in the pBAD-DEST49 vector were expressed at high levels in the Top10 strain. After a systematic screen of 96 detergents, the zwitterionic detergents of the Fos-choline series (FC9-FC16) emerged as the most effective for isolation of the hCRs. The FC14 was selected both for solubilization from bacterial lysates and for stabilization of the Trx-hCRs during purification. Thus, the FC-14 solubilized Trx-hCRs could be purified using size exclusion chromatography as monomers and dimers with the correct apparent MW and their alpha-helical content determined by circular dichroism. The identity of two of the expressed hCRs (CCR3 and CCR5) was confirmed using immunoblots using specific monoclonal antibodies. After optimization of expression systems and detergent-mediated purification procedures, we achieved large-scale, high-level production of 4 human GPCR chemokine receptor in a two

  4. In vitro characterization and inhibition of the CXCR4/CXCL12 chemokine axis in human uveal melanoma cell lines

    Directory of Open Access Journals (Sweden)

    Antecka Emilia

    2007-11-01

    Full Text Available Abstract Purpose The CXCR4/CXCL12 chemokine axis may play a critical role in guiding CXCR4+ circulating malignant cells to organ specific locations that actively secrete its ligand CXCL12 (SDF-1 such as bone, brain, liver, and lungs. We sought to characterize the presence of the CXCR4/CXCL12 axis in five uveal melanoma (UM cell lines in vitro. The ability of TN14003, a synthetic peptide inhibitor that targets the CXCR4 receptor complex, to inhibit this axis was also assessed. Methods Immunocytochemistry was performed against CXCR4 to confirm expression of this chemokine receptor in all five UM cell lines. Flow cytometry was preformed to evaluate CXCR4 cell surface expression on all five UM cell lines. A proliferation assay was also used to test effects TN14003 would have on cellular proliferation. Inhibition of cellular migration by specifically inhibiting the CXCR4/CXCL12 axis with TN14003 was also investigated. The binding efficacy of TN14003 to the CXCR4 receptor was assessed through flow cytometric methods. Results The CXCR4 receptor was present on all five UM cell lines. All five cell lines expressed different relative levels of surface CXCR4. TN14003 did not affect the proliferation of the five cell lines (p > 0.05. All cell lines migrated towards the chemokine CXCL12 at a level greater than the negative control (p Conclusion Interfering with the CXCR4/CXCL12 axis, using TN14003 was shown to effectively down regulate UM cell migration in vitro. Knowing that UM expresses the CXCR4 receptor, these CXCR4+ cells may be less likely to colonize distant organs that secrete the CXCL12 ligand, if treated with an inhibitor that binds CXCR4. Further studies should be pursued in order to test TN14003 efficacy in vivo.

  5. Concise site-specific synthesis of DTPA-peptide conjugates: application to imaging probes for the chemokine receptor CXCR4.

    Science.gov (United States)

    Masuda, Ryo; Oishi, Shinya; Ohno, Hiroaki; Kimura, Hiroyuki; Saji, Hideo; Fujii, Nobutaka

    2011-05-15

    Diethylenetriaminepentaacetic acid (DTPA) is a useful chelating agent for radionuclides such as (68)Ga, (99m)Tc and (111)In, which are applicable to nuclear medicine imaging. In this study, we established a facile synthetic protocol for the production of mono-DTPA-conjugated peptide probes. A novel monoreactive DTPA precursor reagent was synthesized in two steps using the chemistry of the o-nitrobenzenesulfonyl (Ns) protecting group, and under mild conditions this DTPA precursor was incorporated onto an N(ε)-bromoacetylated Lys of a protected peptide resin. The site-specific DTPA conjugation was facilitated by using a highly acid-labile 4-methyltrityl (Mtt) protecting group for the target site of the bioactive peptide during the solid-phase synthesis. A combination of both techniques yielded peptides with disulfide bonds, such as octreotide and polyphemusin II-derived CXCR4 antagonists. DTPA-peptide conjugates were purified in a single step following cleavage from the resin and disulfide bond formation. This site-specific on-resin construction strategy was used for the design and synthesis of a novel In-DTPA-labeled CXCR4 antagonist, which exhibited highly potent inhibitory activity against SDF-1-CXCR4 binding. Copyright © 2011 Elsevier Ltd. All rights reserved.

  6. Expression of chemokine receptor CXCR4 and CCR7 in oral squamous cell carcinoma and their relation to clinicopathological characteristics%口腔鳞癌中趋化因子受体CXCR4和CCR7表达及其与临床病理特征的关系

    Institute of Scientific and Technical Information of China (English)

    尹东; 刘静; 贾咏存; 赵桂治

    2013-01-01

    目的 检测CXC类趋化因子受体4(chemokine CXC motif receptor4,CXCR4)和CC类趋化因子受体7(chemokine CC motif receptor 7,CCR7)在口腔鳞癌(oral squamous cell carcinoma,OSCC)中表达,探讨其与OSCC临床病理特点及颈淋巴结转移的关系.方法 采用免疫组化和反转录聚合酶链反应(RT-PCR)检测64例OSCC组织原发灶、39例转移淋巴结组织和10例正常口腔黏膜组织中CXCR4及CCR7的表达,并分析其与临床病理参数的关系.结果 OSCC组织细胞中CXCR4、CCR7蛋白的阳性表达率分别为62.5%、65.6%,明显高于正常口腔黏膜组织细胞(P<0.01),其中有淋巴结转移组表达率分别为74.36%、84.62%,无淋巴结转移组表达率分别为44%、36%,差异均有统计学意义(P<0.05),而CXCR4、CCR7在淋巴结转移灶中的阳性表达率差异无统计学意义(P>0.05).RT-PCR检测结果也证实,CXCR4及CCR7在OSCC细胞中均有阳性表达.此外,CXCR4及CCR7的表达与肿瘤的分化程度、侵袭程度和TNM分期密切相关(P<0.05),而与年龄、性别和肿瘤大小无关(P>0.05).结论 趋化因子受体CXCR4、CCR7的表达与OSCC侵袭发展和淋巴结转移密切相关.CXCR4、CCR7有可能成为OSCC治疗的新靶点.

  7. Clinical significance of nuclear factor κB and chemokine receptor CXCR4 expression in patients with diffuse large B-cell lymphoma who received rituximab-based therapy.

    Science.gov (United States)

    Shin, Ho Cheol; Seo, Jongwon; Kang, Byung Woog; Moon, Joon Ho; Chae, Yee Soo; Lee, Soo Jung; Lee, Yoo Jin; Han, Seoae; Seo, Sang Kyung; Kim, Jong Gwang; Sohn, Sang Kyun; Park, Tae-In

    2014-11-01

    This study investigated the expression of nuclear factor κB (NF-κB) and the chemokine receptor (CXCR4) in patients with diffuse large B-cell lymphoma (DLBCL) who received rituximab-based therapy. Seventy patients with DLBCL and treated with rituximab-CHOP (R-CHOP) were included, and immunohistochemistry was performed to determine the expression of NF-κB (IκB kinase α, p50, and p100/p52) and CXCR4. To classify DLBCL cases as germinal center B-cell-like (GCB) and non-GCB, additional immunohistochemical expression of CD10, bcl-6, or MUM1 was used in this study. The expression was divided into two groups according to the intensity score (negative, 0 or 1+; positive, 2+ or 3+). The median age of the patients was 66 years (range, 17 to 87), and 58.6% were male. Twenty-seven patients (38.6%) had stage III or IV disease at diagnosis. Twenty-three patients (32.9%) were categorized as high or high-intermediate risk according to their International Prognostic Indexs (IPIs). The overall incidence of bone marrow involvement was 5.7%. Rates of positive NF-κB and CXCR4 expression were 84.2% and 88.6%, respectively. High NF-κB expression was associated with CXCR4 expression (p = 0.002), and 56 patients (80.0%) showed coexpression. However, the expression of NF-κB or CXCR4 was not associated with overall survival and EFS. On multivariate analysis that included age, gender, performance status, stage, and the IPI, no significant association between the grade of NF-κB or CXCR4 expression and survival was observed. The current study suggests that the tissue expression of NF-κB and CXCR4 may not be an independent prognostic marker in DLBCL patients treated with R-CHOP.

  8. 趋化因子受体CXCR4和CCR7在甲状腺癌中的表达及其临床病理意义%Expressions of Chemokine Receptor CXCR4 and CCR7 in Thyroid Cancer and Its Clinicopathologic Significance

    Institute of Scientific and Technical Information of China (English)

    熊斌; 王崇树

    2011-01-01

    目的 探讨趋化因子受体CXCR4和CCR7在甲状腺癌中的表达及其临床病理意义.方法 选取2006~2009年期间在我院行手术治疗的甲状腺癌患者55例和2009年在我院行手术治疗的甲状腺腺瘤患者30例,采用免疫组织化学染色SP法检测甲状腺癌及甲状腺腺瘤组织中的CXCR4和CCR7的表达.结果 CXCR4和CCR7在甲状腺癌中的表达阳性率均明显高于甲状腺腺瘤(P<0.01).CXCR4和CCR7在临床分期为Ⅲ+Ⅳ期的甲状腺癌患者中的表达阳性率均明显高于临床分期为Ⅰ+Ⅱ期者(P<0.05); CCR7在有淋巴结转移的甲状腺癌中的表达阳性率明显高于无淋巴结转移者(P<0.05),而CXCR4的表达阳性率与甲状腺癌患者有无淋巴结转移无关(P>0.05); CXCR4和CCR7在甲状腺癌组织中的表达阳性率与甲状腺癌患者的年龄和性别均无关(P>0.05).在甲状腺癌中,CXCR4阳性表达和CCR7阳性表达呈正相关(rs=0.491,P=0.000).结论 CXCR4和CCR7协同参与了甲状腺癌的进展,可作为判断甲状腺癌预后的指标;CCR7高表达提示甲状腺癌容易发生淋巴结转移.%Objective To investigate the expressions of chemokine receptor CXCR4 and CCR7 in thyroid cancer and its clinicopathologic significance. Methods Fifty-five patients with thyroid cancer were selected in the Affiliated Hospital of North Sichuan Medical College from 2006 to 2009, and 30 patients with thyroid adenoma were selected in the same hospital during 2009. The expressions of CXCR4 and CCR7 were detected in all the selected cases samples (including thyroid cancer and thyroid adenoma) by immunohistochemical SP technique. Results The positive expression rates of CXCR4 and CCR7 in the thyroid cancer were higher than those in the thyroid adenoma (P0. 05)? And which of CXCR4 and CCR7 were also independent of the age and gender of the patients with thyroid cancer (P>0. 05). The positive expressions of CCR7 and CXCR4 in all the patients with thyroid cancer was

  9. Expressions of chemokine SDF-1 and its receptor CXCR4 in epithelial ovarian tumor of elderly patients and its clinical significance%SDF-1/CXCR4在老年卵巢癌组织中的表达及意义

    Institute of Scientific and Technical Information of China (English)

    李雅丽; 辛维政; 王轶英

    2011-01-01

    Objective To investigate the expressions and clinical significance of chemokine SDF-1 and its receptor CXCR4 in elderly patients with epithelial ovarian tumor. Methods 43 cases with epithelial ovarian cancer were studied ran-domly. The expressions of SDF-1 and CXCR4 proteins were detected by Western blotting. Results There were weak ex-pression of SDF-1 and modest expression of CXCR4 in benign ovarian tumor of elderly patients. The expressions of SDF-1 protein and CXCR4 protein were significantly increased in epithelial ovarian cancer, compared with benign ovarian tumor (2.38±0.20 vs 3.32±0.26) (P<0.05). Conclusion SDF-1/CXCR4 may play a role in the malignant transformation of primary ovarian cancer and involve in the initiation, progression and metastasis of ovarian cancer of elderly patients.%目的 探讨趋化因子SDF-1及其受体CXCR4在老年人卜皮性卵巢癌组织中的表达及意义.方法 应用western blotting方法定量检测43例老年患者卜皮性卵巢癌组织中SDF-1和CXCR4的蛋白表达情况.结果 老年人上皮性卵巢癌组织中SDF-1/CXCR4蛋白表达较卵巢良性肿瘤对照组明显增加.其相对表达量分别为(2.38±0.20)和(3.32±0.26),差异具有统计学意义(P<0.05).结论 SDF-1/CXCR4生物学轴可能在老年人卵巢癌的发生与转移过程中起着重要作用.

  10. Study on the correlation between the expression levels of chemokine receptor CCR7,CXCR4 and prognosis of patients with non-small-cell lung cancer%CCR7蛋白和 CXCR4蛋白表达水平与非小细胞肺癌患者的预后及相关性研究

    Institute of Scientific and Technical Information of China (English)

    陈晓东; 任开明; 段琼玉; 宣莹; 吴荣

    2016-01-01

    Objective To observe the expression levels of chemokine receptor CCR7,CXCR4 in non-small-cell lung cancer(NSCLC)tissues,and to explore the correlation between the expression levels of CCR7,CXCR4 and prognosis of patients with non-small-cell lung cancer. Methods Seventy-two patients with NSCLC who were treated in our hospital from March 2012 to May 2013 were enrolled in the study. The expression levels of CCR7,CXCR4 were detected by immunohistochemistry(IHC)in 72 cases of NSCLC tissues and 36 cases of distal normal lung tissues of patients with NSCLC. The correlations between the expression levels of CCR7,CXCR4 and general clinical data of patients as well as between the expression levels of CCR7,CXCR4 and prognosis of patients with NSCLC were analyzed. Results There were significant differences in the expression levels of CCR7,CXCR4 between NSCLC tissues and distal normal lung tissues( P 0. 05). The prognosis of patients with high-expression of CCR7 or CXCR4 was poorer,as compared with that of patients with low-expression of CCR7 or CXCR4, moreover,the expression levels of CCR7 were positively correlated to those of CXCR4 in NSCLC. Conclusion The expression levels of CCR7,CXCR4 in NSCLC tissues are significantly higher than those in distal normal lung tissues,furthermore,the expression levels of CCR7,CXCR4 are closely correlated to clinical stagig and lymph node metastasis of NSCLC. The expression levels of CCR7 are positively related with those of CXCR4,moreover,the prognosis of patients with high-expression of CCR7 or CXCR4 is poorer,as compared with that of patients with low-expression of CCR7 or CXCR4.%目的:通过对比分析 CCR7蛋白、CXCR4蛋白在非小细胞肺癌组织中的表达水平探讨这两种趋化因子表达的相关性以及患者的预后与其相关性。方法选择2012年3月至2013年5月进行非小细胞肺癌治疗的患者72例,分别取每位患者的非小细胞肺癌组织,并且随机选择36例患者的正常组织,

  11. Chemokine co-receptor CCR5/CXCR4-dependent modulation of Kv2.1 channel confers acute neuroprotection to HIV-1 glycoprotein gp120 exposure.

    Directory of Open Access Journals (Sweden)

    Andrew J Shepherd

    Full Text Available Infection with human immunodeficiency virus-1 (HIV-1 within the brain has long been known to be associated with neurodegeneration and neurocognitive disorder (referred as HAND, a condition characterized in its early stages by declining cognitive function and behavioral disturbances. Mechanistically, the HIV-1 coat glycoprotein 120 (gp120 has been suggested to be a critical factor inducing apoptotic cell death in neurons via the activation of p38 mitogen-activated protein kinase (MAPK, upon chronic exposure to the virus. Here we show that acute exposure of neurons to HIV-1 gp120 elicits a homeostatic response, which provides protection against non-apoptotic cell death, involving the major somatodendritic voltage-gated K⁺ (Kv channel Kv2.1 as the key mediator. The Kv2.1 channel has recently been shown to provide homeostatic control of neuronal excitability under conditions of seizures, ischemia and neuromodulation/neuroinflammation. Following acute exposure to gp120, cultured rat hippocampal neurons show rapid dephosphorylation of the Kv2.1 protein, which ultimately leads to changes in specific sub-cellular localization and voltage-dependent channel activation properties of Kv2.1. Such modifications in Kv2.1 are dependent on the activation of the chemokine co-receptors CCR5 and CXCR4, and subsequent activation of the protein phosphatase calcineurin. This leads to the overall suppression of neuronal excitability and provides neurons with a homeostatic protective mechanism. Specific blockade of calcineurin and Kv2.1 channel activity led to significant enhancement of non-apoptotic neuronal death upon acute gp120 treatment. These observations shed new light on the intrinsic homeostatic mechanisms of neuronal resilience during the acute stages of neuro-HIV infections.

  12. Chemokine co-receptor CCR5/CXCR4-dependent modulation of Kv2.1 channel confers acute neuroprotection to HIV-1 glycoprotein gp120 exposure.

    Science.gov (United States)

    Shepherd, Andrew J; Loo, Lipin; Mohapatra, Durga P

    2013-01-01

    Infection with human immunodeficiency virus-1 (HIV-1) within the brain has long been known to be associated with neurodegeneration and neurocognitive disorder (referred as HAND), a condition characterized in its early stages by declining cognitive function and behavioral disturbances. Mechanistically, the HIV-1 coat glycoprotein 120 (gp120) has been suggested to be a critical factor inducing apoptotic cell death in neurons via the activation of p38 mitogen-activated protein kinase (MAPK), upon chronic exposure to the virus. Here we show that acute exposure of neurons to HIV-1 gp120 elicits a homeostatic response, which provides protection against non-apoptotic cell death, involving the major somatodendritic voltage-gated K⁺ (Kv) channel Kv2.1 as the key mediator. The Kv2.1 channel has recently been shown to provide homeostatic control of neuronal excitability under conditions of seizures, ischemia and neuromodulation/neuroinflammation. Following acute exposure to gp120, cultured rat hippocampal neurons show rapid dephosphorylation of the Kv2.1 protein, which ultimately leads to changes in specific sub-cellular localization and voltage-dependent channel activation properties of Kv2.1. Such modifications in Kv2.1 are dependent on the activation of the chemokine co-receptors CCR5 and CXCR4, and subsequent activation of the protein phosphatase calcineurin. This leads to the overall suppression of neuronal excitability and provides neurons with a homeostatic protective mechanism. Specific blockade of calcineurin and Kv2.1 channel activity led to significant enhancement of non-apoptotic neuronal death upon acute gp120 treatment. These observations shed new light on the intrinsic homeostatic mechanisms of neuronal resilience during the acute stages of neuro-HIV infections.

  13. Correlation between chemokine receptor CXCR4, CCR7 in gastric cell fines with different invasive potentials%趋化因子受体CXCR4、CCR7在胃癌细胞中的表达及其与胃癌细胞侵袭能力的关系

    Institute of Scientific and Technical Information of China (English)

    姜明; 郑毅雄; 唐湘莲; 孟立峰; 陈力

    2010-01-01

    目的 观察趋化因子受体CXCR4及CCR7在不同侵袭能力人胃癌细胞株中的差异表达.方法 逆转录-聚合酶链反应(RT-PCR)及Western blot分析CXCR4及CCR7在人胃癌细胞株MGC803、AGS、BGC823、SGC7901的表达;体外侵袭实验测定4株胃癌细胞的侵袭能力.结果 MGC803、AGS、BGC823、SGC7901中CXCR4 mRNA相对表达量分别为:1.2556±0.1384、0.7943±0.0913、0.4749±0.0744、0.2463±0.0344,CCR7 mRNA相对表达量分别为:0.6071±0.1404、0.5355±0.0750、0.2549±0.0522、0.2466±0.0342,CXCR4及CCR7蛋白表达趋势同其相对应的基因表达趋势基本一致.4株胃癌细胞侵袭实验测定的侵袭细胞数分别为:400.0±18.2、310.0±4.0、110.0±13.9、85.0±9.5.CXCR4在不同侵袭能力的胃癌细胞株中存在差异性表达(P<0.05).结论 CXCR4的表达与胃癌细胞侵袭能力成正相关,CCR7的表达与胃癌细胞侵袭能力无明显相关.%Objective To compare the differential expression of chemokine receptors CXCR4 and CCR7 in human gastric carcinoma cell lines with different invasion ability. Methods The expression of CXCR4 and CCR7 in MGC803, AGS, BGC823 and SGC7901 cells was detected by reverse transcription-polymerase chain reaction (RT-PCR) and Western blotting. The invasion ability of gastric cancer cell lines was measured using transwell chamber with matrigle. Results The expression of CXCR4 mRNA in MGC803, AGS, BGC823 and SGC790 cells was 1. 2556 ±0. 1384, 0. 7943 ± 0. 0913, 0. 4749 ± 0. 0744, 0. 2463 ± 0. 0344, that of CCR7 mRNA was 0. 6071 ± 0. 1404, 0. 5355 ± 0. 0750, 0. 2549 ± 0. 0522, 0. 2466 ± 0. 0342, respectively. The protein expression of CXCR4 and CCR7 in four human gastric carcino-ma cell lines showed a good agreement with mRNA expression. The penetrating cell number of MGC803, AGS, BGC823 and SGC790 was 400. 0 ± 18. 2, 310. 0 ±4. 0, 110. 0 ±13.9, 85.0 ± 9. 5, respectively. The expression levels of CXCR4 in cancer cells showed a significant positive correlation

  14. Chemokine axes CXCL12/CXCR4 and CXCL16/CXCR6 correlate with lymph node metastasis in epithelial ovarian carcinoma

    Institute of Scientific and Technical Information of China (English)

    Li Guo; Zhu-Mei Cui; Jia Zhang; Yu Huang

    2011-01-01

    Recent evidence suggests that the chemokine axis of CXC chemokine ligand-12 and its receptor CXC chemokine receptor-4 (CXCL12/CXCR4) is highly expressed in gynecological tumors and the axis of CXC chemokine ligand-16 and CXC chemokine receptor-6 (CXCL16/CXCR6) is overexpressed in inflammation-associated tumors. This study aimed to determine the relationship between CXCL12/CXCR4, CXCL16/CXCR6 and ovadan carcinoma's clinicopathologic features and prognosis. Accordingly, the expression of these proteins in ovarian tissues was detected by tissue microarray and immunohistochemistry. The expressions of CXCL12/CXCR4 and CXCL16/CXCR6 were significantly higher in epithelial ovadan carcinomas than in normal epithelial ovadan tissues or benign epithelial ovadan tumors. The expression of chemokines CXCL12 and CXCL16 were positively correlated with their receptors CXCR4 and CXCR6 in ovarian carcinoma, respectively (r = 0.300, P < 0.05; r = 0.395, P < 0.05). Moreover, the expression of CXCL12 was related to the occurrence of ascites (X2 = 4.76, P < 0.05), the expression of CXCR4 was significantly related to lymph node metastasis (X2 = 4.37, P < 0.05), the expression of CXCR6 was significantly related to lymph node metastasis (X2 = 7.43, P < 0.05) and histological type (X2 = 33.48, P < 0.05). ln univariate analysis, the expression of CXCR4 and CXCL16 significantly correlated with reduced median survival (X2 = 4.67, P < 0.05; X2 = 4.48, P < 0.05). Therefore, we conclude that the chemokine axes CXCL12/CXCR4 and CXCL16/CXCR6 may play important roles in the growth, proliferation, invasion, and metastasis of epithelial ovarian carcinoma.

  15. SDF-1/CXCR4生物轴对胆囊癌细胞增殖及迁移的影响%Effects of chemokine stromal cell-derived factor-1 and its receptor CXCR4 on the proliferation and migration of gallbladder carcinoma cells

    Institute of Scientific and Technical Information of China (English)

    焦兴元; 胡以则

    2008-01-01

    目的 研究胆囊腺癌中趋化因子SDF-1及其受体CXCR4的表达情况,探讨其与胆囊腺癌临床病理特点及淋巴转移的关系.方法 采用免疫组化SP法检测41例胆囊腺癌中SDF-1及其受体CXCR4蛋白阳性表达情况,并分析其与临床病理参数的关系.结果 SDF-1在胆囊癌、胆囊炎、胆囊结石组和正常对照组胆囊黏膜中的表达率分别为68.3%(28/41)、6.7%(6/90)和5.0%(1/20),CXCR4的表达率分别为51.2%(21/41)、5.6%(5/90)和5.0%(1/20),SDF-1和CXCR4在胆囊癌与慢性胆囊炎、胆囊结石组胆囊黏膜、正常对照组胆囊黏膜中的阳性率比较,差异均有统计学意义(SDF-1:χ2=64.33,P<0.001;CXCR4:χ2=42.52,P<0.001),胆囊癌不同病理组织学分级、Nevin不同分期、组织学不同分化程度、有无淋巴结或远处转移组间的SDF-1和CXCR4的阳性率表达差异均有统计学意义(P均<0.05),而不同性别、年龄、有无伴发胆囊结石组、肿瘤大小间SDF-1和CXCR4的阳性率表达差异均无统计学意义(P均>0.05),胆囊癌组织中SDF-1阳性表达率(68.3%)与CX-CR4阳性表达率(51.2%)之间存在显著正相关(r=0.68,P<0.01).结论 本研究表明,SDF-1/CXCR4生物轴与胆囊癌关系密切,提示可以通过干预SDF-1/CXCR4生物轴来治疗胆囊癌.%Objective To study the expression of chemokine stromal cell-derived factor-1 and its receptor CXCR4 in gallbladder carcinoma and evaluate the relationship between the expression of SDF-1 and CXCR4 protein and the clinicopathology,and lymph node metastasis of gallbladder carcinoma.Methods The expression of SDF-1 and CXCR4 protein in 41 cases of gallbladder adenoma carcinoma was examined by immunohistochemical technique(SP),and the relation of SDF-1/CXCR4 biology axis to clinicopathological parameter was also analyzed.Results The positive expression rate of SDF-1 and CXCR4 in gallbladder carcinoma was 68.3%(28/41)and 51.2%(21/41)respectively,in normal gallbladder mucous was 5%(1/20)and

  16. Expression of chemokine receptor CXCR4 and CCR7 in laryngeal carcinoma%趋化因子受体CXCR4和CCR7在喉癌组织中的表达

    Institute of Scientific and Technical Information of China (English)

    张龙; 杨成章; 李明

    2005-01-01

    目的:观察喉癌组织中趋化因子受体CXCR4和CCR7的表达情况,初步了解CXCR4和CCR7与喉癌恶性表现的关系,从而为临床治疗提供理论基础.方法:应用免疫组织化学SP法对实验组30例喉癌组织标本和对照组18例正常喉部黏膜组织标本中的趋化因子受体CXCR4和CCR7的表达进行检测,并应用计算机辅助图像分析仪对表达结果进行图像分析,然后进行统计学分析.结果:①趋化因子受体CXCR4和CCR7蛋白在喉癌组织中呈强阳性表达,且CXCR4和CCR7蛋白表达水平显著高于对照组(P<0.01) ;②癌细胞分化程度高的癌组织趋化因子受体CXCR4和CCR7蛋白表达水平显著低于分化程度低的癌组织(P<0.05),CXCR4和CCR7蛋白表达水平在Ⅲ~Ⅳ期较Ⅰ~Ⅱ期明显升高(P<0.01),淋巴结转移组较无淋巴结转移组均明显升高(P<0.01).结论:趋化因子受体CXCR4和CCR7在喉癌组织中的高表达,其表达水平与喉癌的病理分化程度、临床分期及颈部淋巴结转移有关.

  17. The role of CXC chemokine ligand (CXCL)12-CXC chemokine receptor (CXCR)4 signalling in the migration of neural stem cells towards a brain tumour

    NARCIS (Netherlands)

    van der Meulen, A. A. E.; Biber, K.; Lukovac, S.; Balasubramaniyan, V.; den Dunnen, W. F. A.; Boddeke, H. W. G. M.; Mooij, J. J. A.

    2009-01-01

    Aims: It has been shown that neural stem cells (NSCs) migrate towards areas of brain injury or brain tumours and that NSCs have the capacity to track infiltrating tumour cells. The possible mechanism behind the migratory behaviour of NSCs is not yet completely understood. As chemokines are involved

  18. Chloroquine-Containing HPMA Copolymers as Polymeric Inhibitors of Cancer Cell Migration Mediated by the CXCR4/SDF-1 Chemokine Axis

    OpenAIRE

    Yu, Fei; Xie, Ying; Wang, Yan; Peng, Zheng-Hong; Li, Jing; Oupický, David

    2016-01-01

    Chloroquine-containing HPMA copolymers (pCQs) were synthesized for the first time by copolymerization of methacryloylated hydroxychloroquine and HPMA. The copolymers showed lower cytotoxicity when compared with hydroxychloroquine. Treatment of cancer cells with pCQ resulted in decreased surface expression of chemokine receptor CXCR4. The pCQ copolymers showed effective inhibition of CXCR4/SDF1-mediated cancer cell migration that was fully comparable with a commercial small-molecule CXCR4 anta...

  19. Lead Screening for CXCR4 of the Human HIV Infection Receptor Inhibited by Traditional Chinese Medicine

    Directory of Open Access Journals (Sweden)

    Tzu-Chieh Hung

    2014-01-01

    Full Text Available The acquired immunodeficiency syndrome (AIDS is a serious worldwide disease caused by the human immunodeficiency virus (HIV infection. Recent research has pointed out that the G protein-coupled chemokine receptor CXCR4 and the coreceptor C-C chemokine receptor type 5 (CCR5 are important targets for HIV infection. The traditional Chinese medicine (TCM database has been screened for candidate compounds by simulating molecular docking and molecular dynamics against HIV. Saussureamine C, 5-hydroxy-L-tryptophan, and diiodotyrosine are selected based on the highest docking score. The molecular dynamics is helpful in the analysis and detection of protein-ligand interactions. According to the analysis of docking poses, hydrophobic interactions, hydrogen bond variations, and the comparison of the effect on CXCR4 and CCR5, these results indicate Saussureamine C may have better effect on these two receptors. But for some considerations, diiodotyrosine could make the largest variation and may have some efficacy contrary to expectations.

  20. Molecular mechanism of AMD3100 antagonism in the CXCR4 receptor: transfer of binding site to the CXCR3 receptor

    DEFF Research Database (Denmark)

    Rosenkilde, Mette M; Gerlach, Lars-Ole; Jakobsen, Janus S

    2004-01-01

    AMD3100 is a symmetric bicyclam, prototype non-peptide antagonist of the CXCR4 chemokine receptor. Mutational substitutions at 16 positions located in TM-III, -IV, -V, -VI, and -VII lining the main ligand-binding pocket of the CXCR4 receptor identified three acid residues: Asp(171) (AspIV:20), Asp......, respectively. Metal ion binding in the cyclam rings of AMD3100 increased its dependence on Asp(262) and provided a tighter molecular map of the binding site, where borderline mutational hits became clear hits for the Zn(II)-loaded analog. The proposed binding site for AMD3100 was confirmed by a gradual build...... that AMD3100 binds through interactions with essentially only three acidic anchor-point residues, two of which are located at one end and the third at the opposite end of the main ligand-binding pocket of the CXCR4 receptor. We suggest that non-peptide antagonists with, for example, improved oral...

  1. Thermal stability of the human immunodeficiency virus type 1 (HIV-1 receptors, CD4 and CXCR4, reconstituted in proteoliposomes.

    Directory of Open Access Journals (Sweden)

    Mikhail A Zhukovsky

    Full Text Available BACKGROUND: The entry of human immunodeficiency virus (HIV-1 into host cells involves the interaction of the viral exterior envelope glycoprotein, gp120, and receptors on the target cell. The HIV-1 receptors are CD4 and one of two chemokine receptors, CCR5 or CXCR4. METHODOLOGY/PRINCIPAL FINDINGS: We created proteoliposomes that contain CD4, the primary HIV-1 receptor, and one of the coreceptors, CXCR4. Antibodies against CD4 and CXCR4 specifically bound the proteoliposomes. CXCL12, the natural ligand for CXCR4, and the small-molecule CXCR4 antagonist, AMD3100, bound the proteoliposomes with affinities close to those associated with the binding of these molecules to cells expressing CXCR4 and CD4. The HIV-1 gp120 exterior envelope glycoprotein bound tightly to proteoliposomes expressing only CD4 and, in the presence of soluble CD4, bound weakly to proteoliposomes expressing only CXCR4. The thermal stability of CD4 and CXCR4 inserted into liposomes was examined. Thermal denaturation of CXCR4 followed second-order kinetics, with an activation energy (E(a of 269 kJ/mol (64.3 kcal/mol and an inactivation temperature (T(i of 56°C. Thermal inactivation of CD4 exhibited a reaction order of 1.3, an E(a of 278 kJ/mol (66.5 kcal/mol, and a T(i of 52.2°C. The second-order denaturation kinetics of CXCR4 is unusual among G protein-coupled receptors, and may result from dimeric interactions between CXCR4 molecules. CONCLUSIONS/SIGNIFICANCE: Our studies with proteoliposomes containing the native HIV-1 receptors allowed an examination of the binding of biologically important ligands and revealed the higher-order denaturation kinetics of these receptors. CD4/CXCR4-proteoliposomes may be useful for the study of virus-target cell interactions and for the identification of inhibitors.

  2. Mutation of Asp(171) and Asp(262) of the chemokine receptor CXCR4 impairs its coreceptor function for human immunodeficiency virus-1 entry and abrogates the antagonistic activity of AMD3100

    DEFF Research Database (Denmark)

    Hatse, S; Princen, K; Gerlach, L O

    2001-01-01

    by substitution of Asp(171) and/or Asp(262) by neutral asparagine residue(s). Both aspartates, but most particularly Asp(262), also proved essential for the anti-HIV-1 activity of AMD3100 against the viruses NL4.3, IIIB, and HE. In contrast, substitution of His(281) by a neutral alanine potentiated...... the antagonistic and antiviral effects of the compound in the different assay systems. Importantly, compared with the wild-type receptor, CXCR4[D262N] was much less effective, whereas CXCR4[D171N,D262N] completely failed as a coreceptor for infection by HIV-1 NL4.3. Thus, the negatively charged aspartate residues...

  3. SDF-1α is a novel autocrine activator of platelets operating through its receptor CXCR4.

    Science.gov (United States)

    Walsh, Tony G; Harper, Matthew T; Poole, Alastair W

    2015-01-01

    Platelets store and secrete the chemokine stromal cell-derived factor (SDF)-1α upon platelet activation, but the ability of platelet-derived SDF-1α to signal in an autocrine/paracrine manner mediating functional platelet responses relevant to thrombosis and haemostasis is unknown. We sought to explore the role of platelet-derived SDF-1α and its receptors, CXCR4 and CXCR7 in facilitating platelet activation and determine the mechanism facilitating SDF-1α-mediated regulation of platelet function. Using human washed platelets, CXCR4 inhibition, but not CXCR7 blockade significantly abrogated collagen-mediated platelet aggregation, dense granule secretion and thromboxane (Tx) A2 production. Time-dependent release of SDF-1α from collagen-activated platelets supports a functional role for SDF-1α in this regard. Using an in vitro whole blood perfusion assay, collagen-induced thrombus formation was substantially reduced with CXCR4 inhibition. In washed platelets, recombinant SDF-1α in the range of 20-100 ng/mL(-1) could significantly enhance platelet aggregation responses to a threshold concentration of collagen. These enhancements were completely dependent on CXCR4, but not CXCR7, which triggered TxA2 production and dense granule secretion. Rises in cAMP were significantly blunted by SDF-1α, which could also enhance collagen-mediated Ca2+ mobilisation, both of which were mediated by CXCR4. This potentiating effect of SDF-1α primarily required TxA2 signalling acting upstream of dense granule secretion, whereas blockade of ADP signalling could only partially attenuate SDF-1α-induced platelet activation. Therefore, this study supports a potentially novel autocrine/paracrine role for platelet-derived SDF-1α during thrombosis and haemostasis, through a predominantly TxA2-dependent and ADP-independent pathway.

  4. Cannabinoid receptor 2-mediated attenuation of CXCR4-tropic HIV infection in primary CD4+ T cells.

    Directory of Open Access Journals (Sweden)

    Cristina Maria Costantino

    Full Text Available Agents that activate cannabinoid receptor pathways have been tested as treatments for cachexia, nausea or neuropathic pain in HIV-1/AIDS patients. The cannabinoid receptors (CB(1R and CB(2R and the HIV-1 co-receptors, CCR5 and CXCR4, all signal via Gαi-coupled pathways. We hypothesized that drugs targeting cannabinoid receptors modulate chemokine co-receptor function and regulate HIV-1 infectivity. We found that agonism of CB(2R, but not CB(1R, reduced infection in primary CD4+ T cells following cell-free and cell-to-cell transmission of CXCR4-tropic virus. As this change in viral permissiveness was most pronounced in unstimulated T cells, we investigated the effect of CB(2R agonism on to CXCR4-induced signaling following binding of chemokine or virus to the co-receptor. We found that CB(2R agonism decreased CXCR4-activation mediated G-protein activity and MAPK phosphorylation. Furthermore, CB(2R agonism altered the cytoskeletal architecture of resting CD4+ T cells by decreasing F-actin levels. Our findings suggest that CB(2R activation in CD4+ T cells can inhibit actin reorganization and impair productive infection following cell-free or cell-associated viral acquisition of CXCR4-tropic HIV-1 in resting cells. Therefore, the clinical use of CB(2R agonists in the treatment of AIDS symptoms may also exert beneficial adjunctive antiviral effects against CXCR4-tropic viruses in late stages of HIV-1 infection.

  5. Expression of the CXCL12/CXCR4 chemokine axis predicts regional control in head and neck squamous cell carcinoma.

    Science.gov (United States)

    León, Xavier; Diez, Santiago; García, Jacinto; Lop, Joan; Sumarroca, Anna; Quer, Miquel; Camacho, Mercedes

    2016-12-01

    Expression of the CXCL12/CXCR4 chemokine axis has been related with the appearance of metastatic recurrence survival, including regional and distant recurrence, in patients with head and neck squamous cell carcinoma (HNSCC). RT-PCR was used to determine mRNA expression levels of CXCL12 and CXCR4 in biopsy tumor samples in 111 patients with HNSCC. Five-year regional recurrence-free survival for patients with low CXCR4 expression (n = 39, 31.5 %) was 97.4 %, for patients with high CXCR4/high CXCL12 expression (n = 22, 19.8 %) it was 94.7 %, and for patients with high CXCR4/low CXCL12 expression (n = 50, 45.0 %) it was 63.3 %. We found significant differences in the regional recurrence-free survival according to CXCR4/CXCL12 expression values (P = 0.001). HNSCC patients with high CXCR4 and low CXCL12 expression values had a significantly higher risk of regional recurrence and could benefit from a more intense treatment of lymph node areas in the neck.

  6. Impaired recruitment of Grk6 and beta-Arrestin 2 causes delayed internalization and desensitization of a WHIM syndrome-associated CXCR4 mutant receptor.

    Directory of Open Access Journals (Sweden)

    Peter J McCormick

    Full Text Available WHIM (warts, hypogammaglobulinemia, infections, and myelokatexis syndrome is a rare immunodeficiency syndrome linked to heterozygous mutations of the chemokine receptor CXCR4 resulting in truncations of its cytoplasmic tail. Leukocytes from patients with WHIM syndrome display impaired CXCR4 internalization and enhanced chemotaxis in response to its unique ligand SDF-1/CXCL12, which likely contribute to the clinical manifestations. Here, we investigated the biochemical mechanisms underlying CXCR4 deficiency in WHIM syndrome. We report that after ligand activation, WHIM-associated mutant CXCR4 receptors lacking the carboxy-terminal 19 residues internalize and activate Erk 1/2 slower than wild-type (WT receptors, while utilizing the same trafficking endocytic pathway. Recruitment of beta-Arrestin 2, but not beta-Arrestin 1, to the active WHIM-mutant receptor is delayed compared to the WT CXCR4 receptor. In addition, while both kinases Grk3 and Grk6 bind to WT CXCR4 and are critical to its trafficking to the lysosomes, Grk6 fails to associate with the WHIM-mutant receptor whereas Grk3 associates normally. Since beta-Arrestins and Grks play critical roles in phosphorylation and internalization of agonist-activated G protein-coupled receptors, these results provide a molecular basis for CXCR4 dysfunction in WHIM syndrome.

  7. Impaired Recruitment of Grk6 and β-Arrestin2 Causes Delayed Internalization and Desensitization of a WHIM Syndrome-Associated CXCR4 Mutant Receptor

    Science.gov (United States)

    McCormick, Peter J.; Segarra, Marta; Gasperini, Paola; Gulino, A. Virginia; Tosato, Giovanna

    2009-01-01

    WHIM (warts, hypogammaglobulinemia, infections, and myelokatexis) syndrome is a rare immunodeficiency syndrome linked to heterozygous mutations of the chemokine receptor CXCR4 resulting in truncations of its cytoplasmic tail. Leukocytes from patients with WHIM syndrome display impaired CXCR4 internalization and enhanced chemotaxis in response to its unique ligand SDF-1/CXCL12, which likely contribute to the clinical manifestations. Here, we investigated the biochemical mechanisms underlying CXCR4 deficiency in WHIM syndrome. We report that after ligand activation, WHIM-associated mutant CXCR4 receptors lacking the carboxy-terminal 19 residues internalize and activate Erk 1/2 slower than wild-type (WT) receptors, while utilizing the same trafficking endocytic pathway. Recruitment of β-Arrestin 2, but not β-Arrestin 1, to the active WHIM-mutant receptor is delayed compared to the WT CXCR4 receptor. In addition, while both kinases Grk3 and Grk6 bind to WT CXCR4 and are critical to its trafficking to the lysosomes, Grk6 fails to associate with the WHIM-mutant receptor whereas Grk3 associates normally. Since β-Arrestins and Grks play critical roles in phosphorylation and internalization of agonist-activated G protein-coupled receptors, these results provide a molecular basis for CXCR4 dysfunction in WHIM syndrome. PMID:19956569

  8. Mycobacterium tuberculosis-induced CXCR4 and chemokine expression leads to preferential X4 HIV-1 replication in human macrophages.

    Science.gov (United States)

    Hoshino, Yoshihiko; Tse, Doris B; Rochford, Gemma; Prabhakar, Savita; Hoshino, Satomi; Chitkara, Nishay; Kuwabara, Kenichi; Ching, Elbert; Raju, Bindu; Gold, Jeffrey A; Borkowsky, William; Rom, William N; Pine, Richard; Weiden, Michael

    2004-05-15

    Opportunistic infections such as pulmonary tuberculosis (TB) increase local HIV-1 replication and mutation. As AIDS progresses, alteration of the HIV-1 gp120 V3 sequence is associated with a shift in viral coreceptor use from CCR5 (CD195) to CXCR4 (CD184). To better understand the effect of HIV/TB coinfection, we screened transcripts from bronchoalveolar lavage cells with high density cDNA arrays and found that CXCR4 mRNA is increased in patients with TB. Surprisingly, CXCR4 was predominately expressed on alveolar macrophages (AM). Mycobacterium tuberculosis infection of macrophages in vitro increased CXCR4 surface expression, whereas amelioration of disease reduced CXCR4 expression in vivo. Bronchoalveolar lavage fluid from TB patients had elevated levels of CCL4 (macrophage inflammatory protein-1beta), CCL5 (RANTES), and CX3CL1 (fractalkine), but not CXCL12 (stromal-derived factor-1alpha). We found that M. tuberculosis infection of macrophages in vitro increased viral entry and RT of CXCR4-using [corrected] HIV-1, but not of CCR5-using [corrected] HIV-1. Lastly, HIV-1 derived from the lung contains CD14, suggesting that they were produced in AM. Our results demonstrate that TB produces a permissive environment for replication of CXCR4-using virus by increasing CXCR4 expression in AM and for suppression of CCR5-using HIV-1 by increasing CC chemokine expression. These changes explain in part why TB accelerates the course of AIDS. CXCR4 inhibitors are a rational therapeutic approach in HIV/TB coinfection.

  9. A synthetic peptide derived from human immunodeficiency virus type 1 gp120 downregulates the expression and function of chemokine receptors CCR5 and CXCR4 in monocytes by activating the 7-transmembrane G-protein-coupled receptor FPRL1/LXA4R.

    Science.gov (United States)

    Deng, X; Ueda, H; Su, S B; Gong, W; Dunlop, N M; Gao, J L; Murphy, P M; Wang, J M

    1999-08-15

    Because envelope gp120 of various strains of human immunodeficiency virus type 1 (HIV-1) downregulates the expression and function of a variety of chemoattractant receptors through a process of heterologous desensitization, we investigated whether epitopes derived from gp120 could mimic the effect. A synthetic peptide domain, designated F peptide, corresponding to amino acid residues 414-434 in the V4-C4 region of gp120 of the HIV-1 Bru strain, potently reduced monocyte binding and chemotaxis response to macrophage inflammatory protein 1beta (MIP-1beta) and stromal cell-derived factor 1alpha (SDF-1alpha), chemokines that use the receptors CCR5 and CXCR4, respectively. Further study showed that F peptide by itself is an inducer of chemotaxis and calcium mobilization in human monocytes and neutrophils. In cross-desensitization experiments, among the numerous chemoattractants tested, only the bacterial chemotactic peptide fMLF, when used at high concentrations, partially attenuated calcium mobilization induced by F peptide in phagocytes, suggesting that this peptide domain might share a 7-transmembrane, G-protein-coupled receptor with fMLF. By using cells transfected with cDNAs encoding receptors that interact with fMLF, we found that F peptide uses an fMLF receptor variant, FPRL1, as a functional receptor. The activation of monocytes by F peptide resulted in downregulation of the cell surface expression of CCR5 and CXCR4 in a protein kinase C-dependent manner. These results demonstrate that activation of FPRL1 on human moncytes by a peptide domain derived from HIV-1 gp120 could lead to desensitization of cell response to other chemoattractants. This may explain, at least in part, the initial activation of innate immune responses in HIV-1-infected patients followed by immune suppression.

  10. Evaluation of assay interference and interpretation of CXCR4 receptor occupancy results in a preclinical study with MEDI3185, a fully human antibody to CXCR4

    Science.gov (United States)

    Chavez, Carlos; Henderson, Simon; Vainshtein, Inna; Standifer, Nathan; DelNagro, Christopher; Mehrzai, Freshta; Schneider, Amy; Roskos, Lorin; Liang, Meina

    2015-01-01

    Background Receptor occupancy (RO) assays provide a means to measure the direct interaction of therapeutics with their cell surface targets. Free receptor assays quantify cell‐surface receptors not bound by a therapeutic while total receptor assays quantify the amount of target on the cell surface. Methods We developed both a flow cytometry‐based free RO assay to detect free surface CXCR4, and a total surface CXCR4 assay. In an effort to evaluate potential displacement interference, we performed in vitro experiments to compare on‐cell affinity with the IC50 values from in vitro and in vivo from the free CXCR4 assay. We determined free and total surface CXCR4 on circulating blood cells in cynomolgus monkeys dosed with MEDI3185, a fully human monoclonal antibody to CXCR4. Results We devised an approach to evaluate displacement interference during assay development and showed that our free assay demonstrated little to no displacement interference. After dosing cynomolgus monkeys with MEDI3185, we observed dose‐dependence in the magnitude and duration of receptor occupancy and found CXCR4 to increase on lymphocytes, monocytes, and granulocytes. In a multiple dose study, we observed time points where surface CXCR4 appeared fully occupied but MEDI3185 was not detectable in serum. These paradoxical results represented a type of assay interference, and by comparing pharmacokinetic, ADA and total CXCR4 results, the most likely reason for the free CXCR4 results was the emergence of neutralizing anti‐drug antibodies (ADA). The total CXCR4 assay was unaffected by ADA and provided a reliable marker of target modulation in both in vivo studies. © 2015 The Authors Cytometry Part B: Clinical Cytometry Published byWiley Periodicals, Inc. PMID:26384735

  11. Phenotypic and functional evidence for the expression of CXCR4 receptor during megakaryocytopoiesis.

    Science.gov (United States)

    Rivière, C; Subra, F; Cohen-Solal, K; Cordette-Lagarde, V; Letestu, R; Auclair, C; Vainchenker, W; Louache, F

    1999-03-01

    The identification of stromal cell-derived factor (SDF)-1alpha as a chemoattractant for human progenitor cells suggests that this chemokine and its receptor might represent critical determinants for the homing, retention, and exit of precursor cells from hematopoietic organs. In this study, we investigated the expression profile of CXCR4 receptor and the biological activity of SDF-1alpha during megakaryocytopoiesis. CD34(+) cells from bone marrow and cord blood were purified and induced to differentiate toward the megakaryocyte lineage by a combination of stem-cell factor (SCF) and recombinant human pegylated megakaryocyte growth and development factor (PEG-rhuMGDF). After 6 days of culture, a time where mature and immature megakaryocytes were present, CD41(+) cells were immunopurified and CXCR4mRNA expression was studied. High transcript levels were detected by a RNase protection assay in cultured megakaryocytes derived from cord blood CD34(+) cells as well as in peripheral blood platelets. The transcript levels were about equivalent to that found in activated T cells. By flow cytometry, a large fraction (ranging from 30% to 100%) of CD41(+) cells showed high levels of CXCR4 antigen on their surface, its expression increasing in parallel with the CD41 antigen during megakaryocytic differentiation. CXCR4 protein was also detected on peripheral blood platelets. SDF-1alpha acts on megakaryocytes by inducing intracellular calcium mobilization and actin polymerization. In addition, in in vitro transmigration experiments, a significant proportion of megakaryocytes was observed to respond to this chemokine. This cell migration was inhibited by pertussis toxin, indicating coupling of this signal to heterotrimeric guanine nucleotide binding proteins. Although a close correlation between CD41a and CXCR4 expession was observed, cell surface markers as well as morphological criteria indicate a preferential attraction of immature megakaryocytes (low level of CD41a and CD42a

  12. 趋化因子受体CXCR4及CCR5真核表达载体的构建及其在卵巢癌细胞中的表达%Construction and expression of vectors carrying chemokine receptors CXCR4/CCR5 in SKOV3 cells

    Institute of Scientific and Technical Information of China (English)

    谢婷婷; 魏莉; 宋辉; 于月成

    2010-01-01

    目的:构建人CXCR4及CCR5真核表达重组质粒,转染人卵巢癌细胞SKOV3,建立稳定转染细胞系并观察其表达效果.方法:从人外周血单个核细胞中提取RNA,采用反转录PCR技术扩增CXCR4及CCR5的基因编码序列,将序列克隆至真核表达载体pEGFP,经酶切和测序鉴定后,应用脂质体转染技术将质粒cancer.pEGFP-CXCR4和pEGFP-CCR5分别导入不表达CXCR4及CCR5蛋白的SKOV3细胞,经G418抗性筛选得到阳性细胞克隆并扩大培养成系.分别采用免疫荧光染色和流式细胞术方法(FCM)检测稳定转染细胞株CXCR4和CCR5的表达.结果:构建了真核表达载体pEG-FP-CXCR4和pEGFP-CCR5;得到了抗G418阳性细胞克隆;免疫荧光染色和FCM检测结果显示,转染质粒的SKOV3细胞表达CXCR4和CCR5.结论:成功建立稳定表达趋化因子受体CXCR4和CCR5的卵巢癌细胞株,为CXCR4和CCR5在卵巢癌中的研究工作提供依据及平台.

  13. 非小细胞肺癌中SDF-1、CXCR4的表达及临床意义%The Expressions of Stromal-Cell Derived Factor 1 (SDF-1), CXC Chemokin Receptor 4 (CXCR4) and their Clinical Significances in Human Non-small Cell Lung Cancer

    Institute of Scientific and Technical Information of China (English)

    蔡永芳; 辛建保; 石新兰; 田淑君

    2006-01-01

    目的 探讨基质细胞衍生因子(SDF-1)及其受体CXCR4在非小细胞肺癌(NSCLC)中的表达及临床意义.方法 利用免疫组织化学方法在40例NSCLC和10例对照组肺组织中检测SDF-1、CXCR4的表达.结果 在NSCLC中,SDF-1、CXCR4的阳性表达率分别为65.00%(26/40)、45.00%(18/40),与对照组肺组织比较均有显著性差异(P<0.01,P<0.05).SDF-1、CXCR4的表达与肺癌细胞分化程度、淋巴结转移和组织学类型密切相关(P<0.01,P<0.05),而与性别、年龄无相关性(P>0.05),在NSCLC中,SDF-1和CXCR4表达之间无显著相关性(P>0.05).结论 SDF-1、CXCR4的表达与肺癌分化程度及转移有关,可作为临床预测肺癌患者预后的指标.

  14. A Chemokine Receptor, CXCR4, Which Is Regulated by Hypoxia-Inducible Factor 2α, Is Crucial for Functional Endothelial Progenitor Cells Migration to Ischemic Tissue and Wound Repair

    Science.gov (United States)

    Tu, Tran Cam; Nagano, Masumi; Yamashita, Toshiharu; Hamada, Hiromi; Ohneda, Kinuko; Kimura, Kenichi

    2016-01-01

    Endothelial progenitor cells (EPCs) have the ability to form new blood vessels and protect ischemic tissues from damage. We previously reported that EPCs with low activity of aldehyde dehydrogenase (Alde-Low EPCs) possess the greater ability to treat ischemic tissues compared with Alde-High EPCs. The expression level of the hypoxia-inducible factors (HIFs), HIF-1α and HIF-2α, was found to be greater in Alde-Low EPCs than in Alde-High EPCs. However, the precise role of the HIF factors in the regulation of EPC activity remains obscure. In this study, we demonstrate a critical role of HIF-2α and its target gene CXCR4 for controlling the migratory activity of EPC to ischemic tissue. We found that coculture of Alde-High EPCs with microvesicles derived from Alde-Low EPCs improved their ability to repair an ischemic skin flap, and the expression of CXCR4 and its ligand SDF1 was significantly increased following the coculture. In Alde-Low EPCs, the expression of CXCR4 was suppressed by short hairpin RNA (shRNA)-mediated HIF-2α, but not HIF-1α downregulation. Chromatin immunoprecipitation assays showed that HIF-2α, but not HIF-1α, binds to the promoter region of CXCR4 gene. The CXCR4 shRNA treatment in Alde-Low EPCs almost completely abrogated their migratory activity to ischemic tissues, whereas the reduction of vascular endothelial growth factor (VEGF) showed much less effect. The CXCR4 overexpression in Alde-High EPCs resulted in a partial, but significant improvement in their repairing ability in an ischemic skin flap. Collectively, these findings indicate that the CXCR4/SDF-1 axis, which is specifically regulated by HIF-2α, plays a crucial role in the regulation of EPC migration to ischemic tissues. PMID:26620723

  15. Expression of Chemokine Receptor Type 4 in New Born Rat Cochleae%趋化因子受体CXCR4在新生大鼠耳蜗的表达变化

    Institute of Scientific and Technical Information of China (English)

    张文; 张璐; 岳波; 宋勇莉; 陈晓栋; 陈阳; 邱建华

    2015-01-01

    目的:通过检测CXCR4在大鼠耳蜗组织发育不同阶段的表达,探究其在哺乳动物耳蜗发育中的作用。方法收集出生后1、7、14和28天的大鼠耳蜗组织,应用RT-PCR和Western Blot方法从mRNA和蛋白水平检测CXCR4的表达变化,同时检测14天和28天大鼠的听性脑干反应(auditory brainstem response,ABR)。结果在新生大鼠耳蜗发育过程中,CXCR4在P1和P7的SD大鼠耳蜗有显著表达,而在P14和P28的大鼠耳蜗中表达微弱。P14大鼠ABR反应阈值范围在20~50dBSPL,平均33±9.23 dBSPL;P28大鼠ABR反应阈值范围在20~40dBSPL,平均30±8.58 dBSPL。结论 CXCR4与新生大鼠耳蜗的早期发育相关,可能参与调控大鼠耳蜗听觉的形成过程。%Objective To study the role of CXCR4 in mammals cochlea development by examining its expression in rat cochlear tissues at different times after birth. Methods Cochlear tissues were collected from SD rats on P1, P7, P14 and P28 days. RT-PCR was used to detect CXCR4 mRNA expression and Western Blot was used to detect CXCR4 protein expres-sion. Auditory brainstem responses (ABR) were tested in 20 rats on P14 and P28 days and results were analyzed. Results The results showed that CXCR4 was highly expressed in cochlear tissues in rats on P1 and P7 days but expression declined on P14 and P28 days. Mean ABR threshold was 33±9.23 dB SPL on P14 day and 30±8.58 dB SPL on P28 day. Conclusion Our results indicate that CXCR4 may play a role in the maturation of rat cochleae and may be involved in modulating devel-opment of the new born cochlea.

  16. Notch pathway promotes ovarian cancer growth and migration via CXCR4/SDF1α chemokine system.

    Science.gov (United States)

    Chiaramonte, R; Colombo, M; Bulfamante, G; Falleni, M; Tosi, D; Garavelli, S; De Simone, D; Vigolo, E; Todoerti, K; Neri, A; Platonova, N

    2015-09-01

    Ovarian cancer is the most deadly gynecological malignancy. Understanding the molecular pathogenesis of ovarian cancer is critical to provide new targeted therapeutic strategies. Recent evidence supports a role for Notch in ovarian cancer progression and associates its dysregulation to poor overall survival. Similarly, CXCR4/SDF1α signalling correlates with ovarian cancer progression and metastasis. Recent findings indicate that Notch promotes CXCR4/SDF1α signalling and its effect on cell growth and migration; nonetheless, up to now, the association between Notch and CXCR4/SDFα in ovarian cancer has not been reported. Thereby, the aim of this study was to investigate if Notch and CXCR4/SDF1α cooperate in determining ovarian cancer growth, survival and migration. To address this issue, Notch signalling was inhibited by using γ-secretase inhibitors, or upregulated by forcing of Notch1 expression in ovarian cancer cell lines. Our results indicated that Notch activity influenced tumour cell growth and survival and positively regulated CXCR4 and SDF1α expression. CXCR4/SDF1α signalling mediated the effect of Notch pathway on ovarian cancer cell growth and SDF1α-driven migration. Additionally, for the first time, we demonstrated that Notch signalling activation can be detected in ovarian cancer specimens by immunohistochemistry analysis of the Notch transcriptional target, HES6 and is positively correlated with high expression levels of CXCR4 and SDF1α. Our results demonstrate that Notch affects ovarian cancer cell biology through the modulation of CXCR4/SDF1α signalling and suggest that Notch inhibition may be a rationale therapeutic approach to hamper ovarian cancer progression mediated by the CXCR4/SDF1α axis.

  17. Bryostatin-5 blocks stromal cell-derived factor-1 induced chemotaxis via desensitization and down-regulation of cell surface CXCR4 receptors.

    Science.gov (United States)

    He, Xing; Fang, Liyan; Wang, Jue; Yi, Yanghua; Zhang, Shuyu; Xie, Xin

    2008-11-01

    The chemokine receptor CXCR4 and its ligand, stromal cell-derived factor-1 (SDF-1), play important roles in hematopoiesis regulation, lymphocyte activation, and trafficking, as well as in developmental processes, including organogenesis, vascularization, and embryogenesis. The receptor is also involved in HIV infection and tumor growth and metastasis. Antagonists of CXCR4 have been widely evaluated for drugs against HIV and tumors. In an effort to identify novel CXCR4 antagonists, we screened a small library of compounds derived from marine organisms and found bryostatin-5, which potently inhibits chemotaxis induced by SDF-1 in Jurkat cells. Bryostatin-5 is a member of the macrolactones, and its analogue bryostatin-1 is currently being evaluated in clinical trials for its chemotherapeutic potential. The involvement of bryostatins in the SDF-1/CXCR4 signaling process has never been reported. In this study, we found that bryostatin-5 potently inhibits SDF-1-induced chemotaxis but does not affect serum-induced chemotaxis. Further studies indicate that this inhibitory effect is not due to receptor antagonism but rather to bryostatin-5-induced receptor desensitization and down-regulation of cell surface CXCR4. We also show that these effects are mediated by the activation of conventional protein kinase C.

  18. Phenotypic Knockout of HIV-1 Chemokine Coreceptor CXCR4 and CCR5 by Intrakines for Blocking HIV-1 Infection

    Institute of Scientific and Technical Information of China (English)

    张颖; 张岩; 王平忠; 王九平; 黄长形; 孙永涛; 白雪帆

    2004-01-01

    To investigate the phenotypic knockout of HIV-1 chemokine coreceptor CXCR4 and CCR5 by intrakines and its inhibitory effect on HIV-1 infection. Primary human PBLs were transduced with the recombinant vector pLNCX-R-K-S-K(△NGFR), followed by anti-NGFR/anti-IgG-magnetic bead method selection and FCM detection. The transduced PBLs were infected with DP1 HIV-1 virus thereafter envelope-mediated syncytium formation and p24 detection were carried out to study the blockage of HIV-1 infection by co-inactivation of CCR5 and CXCR4. pLNCX-R-K-S-K (△NGFR)-transduced PBILs were isolated with an anti-NGFR/anti-IgG-magnetic bead method. After isolation, about 70% of the PBLs were positive for the NGFR marker. When the transduced PBLs were infected with DP1 HIV-1 virus, envelop-mediated syncytium formation was almost completely inhibited by pLNCX-R-K-S-K(△NGFR) transfection. Also, p24 antigen was very low in the cultures of pLNCX-R-K-S-K (△NGFR) transduced PBLs. pLNCX-R-K-S-K(△NGFR) transduction inhibited the production of DP1 p24 antigen by 15%, 43% and 19% on days 4, 7 and 10 respectively. The lymphocytes with the phenotypic knockout of CCR5 and CXCR4 could protect primary human PBLs from DP1 HIV-1 virus infection.

  19. CXCR4-specific Nanobodies as potential therapeutics for WHIM syndrome

    DEFF Research Database (Denmark)

    de Wit, Raymond H; Heukers, Raimond; Brink, Hendrik

    2017-01-01

    WHIM syndrome is a rare congenital immunodeficiency disease, named after its main clinical manifestations: Warts, Hypogammaglobulinemia, Infections and Myelokathexis. The disease is primarily caused by C-terminal truncation mutations of the chemokine receptor CXCR4. Consequently, these CXCR4-WHIM...

  20. Determination of the binding mode for the cyclopentapeptide CXCR4 antagonist FC131 using a dual approach of ligand modifications and receptor mutagenesis

    DEFF Research Database (Denmark)

    Thiele, Stefanie; Mungalpara, J; Steen, A

    2014-01-01

    pocket) respectively. Arg(1) forms charge-charge interactions with Asp(187) in ECL-2, while D-Tyr(5) points to the extracellular side of CXCR4. Furthermore, the backbone of FC131 interacts with the chemokine receptor-conserved Glu(288) via two water molecules. Intriguingly, Tyr(116) and Glu(288) form a H......BACKGROUND AND PURPOSE: The cyclopentapeptide FC131 (cyclo(-L-Arg(1) -L-Arg(2) -L-2-Nal(3) -Gly(4) -D-Tyr(5) -)) is an antagonist at the CXC chemokine receptor CXCR4, which plays a role in human immunodeficiency virus infection, cancer and stem cell recruitment. Binding modes for FC131 in CXCR4...... activation) of FC131 and three analogues were performed on wild-type CXCR4 and 25 receptor mutants. Computational modelling was used to rationalize the experimental data. KEY RESULTS: The Arg(2) and 2-Nal(3) side chains of FC131 interact with residues in TM-3 (His(113) , Asp(171) ) and TM-5 (hydrophobic...

  1. The role of CXCL12-CXCR4 signaling pathway in pancreatic development

    DEFF Research Database (Denmark)

    Katsumoto, Keiichi; Kume, Shoen

    2013-01-01

    Chemokine (C-X-C motif) receptor 4 (CXCR4) is the receptor for chemokine (C-X-C motif) ligand 12 (CXCL12, also known as stromal derived factor-1, Sdf1). CXCR4, a protein consisting 352 amino acids, is known to transduce various signals such as cell differentiation, cell survival, cell proliferation...

  2. CXCR4 in breast cancer: oncogenic role and therapeutic targeting

    Directory of Open Access Journals (Sweden)

    Xu C

    2015-08-01

    Full Text Available Chao Xu,1,* Hong Zhao,1,* Haitao Chen,1 Qinghua Yao2,3 1First Clinical College of Zhejiang Chinese Medical University, 2Department of Integrated Traditional Chinese and Western Medicine, Zhejiang Cancer Hospital, 3Key Laboratory of Integrated Traditional Chinese and Western Medicine, Zhejiang Cancer Hospital, Hangzhou, People’s Republic of China *These authors contributed equally to this work Abstract: Chemokines are 8–12 kDa peptides that function as chemoattractant cytokines and are involved in cell activation, differentiation, and trafficking. Chemokines bind to specific G-protein-coupled seven-span transmembrane receptors. Chemokines play a fundamental role in the regulation of a variety of cellular, physiological, and developmental processes. Their aberrant expression can lead to a variety of human diseases including cancer. C-X-C chemokine receptor type 4 (CXCR4, also known as fusin or CD184, is an alpha-chemokine receptor specific for stromal-derived-factor-1 (SDF-1 also called CXCL12. CXCR4 belongs to the superfamily of the seven transmembrane domain heterotrimeric G protein-coupled receptors and is functionally expressed on the cell surface of various types of cancer cells. CXCR4 also plays a role in the cell proliferation and migration of these cells. Recently, CXCR4 has been reported to play an important role in cell survival, proliferation, migration, as well as metastasis of several cancers including breast cancer. This review is mainly focused on the current knowledge of the oncogenic role and potential drugs that target CXCR4 in breast cancer. Additionally, CXCR4 proangiogenic molecular mechanisms will be reviewed. Strict biunivocal binding affinity and activation of CXCR4/CXCL12 complex make CXCR4 a unique molecular target for prevention and treatment of breast cancer. Keywords: breast cancer, CXCR4, drug target, chemokine, angiogenesis

  3. Cyclophosphamide-induced cystitis increases bladder CXCR4 expression and CXCR4-macrophage migration inhibitory factor association.

    Directory of Open Access Journals (Sweden)

    Pedro L Vera

    Full Text Available BACKGROUND: Macrophage migration inhibitory factor (MIF is a pro-inflammatory cytokine involved in cystitis and a non-cognate ligand of the chemokine receptor CXCR4 in vitro. We studied whether CXCR4-MIF associations occur in rat bladder and the effect of experimental cystitis. METHODS AND FINDINGS: Twenty male rats received saline or cyclophosphamide (40 mg/kg; i.p.; every 3(rd day to induce persistent cystitis. After eight days, urine was collected and bladders excised under anesthesia. Bladder CXCR4 and CXCR4-MIF co-localization were examined with immunhistochemistry. ELISA determined MIF and stromal derived factor-1 (SDF-1; cognate ligand for CXCR4 levels. Bladder CXCR4 expression (real-time RTC-PCR and protein levels (Western blotting were examined. Co-immunoprecipitations studied MIF-CXCR4 associations.Urothelial basal and intermediate (but not superficial cells in saline-treated rats contained CXCR4, co-localized with MIF. Cyclophosphamide treatment caused: 1 significant redistribution of CXCR4 immunostaining to all urothelial layers (especially apical surface of superficial cells and increased bladder CXCR4 expression; 2 increased urine MIF with decreased bladder MIF; 3 increased bladder SDF-1; 4 increased CXCR4-MIF associations. CONCLUSIONS: These data demonstrate CXCR4-MIF associations occur in vivo in rat bladder and increase in experimental cystitis. Thus, CXCR4 represents an alternative pathway for MIF-mediated signal transduction during bladder inflammation. In the bladder, MIF may compete with SDF-1 (cognate ligand to activate signal transduction mediated by CXCR4.

  4. CXCL12/CXCR4 chemokine signaling in spinal glia induces pain hypersensitivity through MAPKs-mediated neuroinflammation in bone cancer rats.

    Science.gov (United States)

    Hu, Xue-Ming; Liu, Yan-Nan; Zhang, Hai-Long; Cao, Shou-Bin; Zhang, Ting; Chen, Li-Ping; Shen, Wen

    2015-02-01

    The activation of MAPK pathways in spinal cord and subsequent production of proinflammatory cytokines in glial cells contribute to the development of spinal central sensitization, the basic mechanism underlying bone cancer pain (BCP). Our previous study showed that spinal CXCL12 from astrocytes mediates BCP generation by binding to CXCR4 in both astrocyters and microglia. Here, we verified that CXCL12/CXCR4 signaling contributed to BCP through a MAPK-mediated mechanism. In naïve rats, a single intrathecal administration of CXCL12 considerably induced pain hyperalgesia and phosphorylation expression of spinal MAPK members (including extracellular signal-regulated kinase, p38, and c-Jun N-terminal kinase), which could be partially prevented by pre-treatment with CXCR4 inhibitor AMD3100. This CXCL12-induced hyperalgesia was also reduced by MAPK inhibitors. In bone cancer rats, tumor cell inoculation into the tibial cavity caused prominent and persistent pain hyperalgesia, and associated with up-regulation of CXCL12 and CXCR4, activation of glial cells, phosphorylation of MAPKs, and production of proinflammatory cytokines in the spinal cord. These tumor cell inoculation-induced behavioral and neurochemical alterations were all suppressed by blocking CXCL12/CXCR4 signaling or MAPK pathways. Taken together, these results demonstrate that spinal MAPK pathways mediated CXCL12/CXCR4-induced pain hypersensitivity in bone cancer rats, which could be druggable targets for alleviating BCP and glia-derived neuroinflammation. Following tumor cell inoculation, chemokine CXCL12 from astrocytes spreads around the spinal environment, resulting in functional activation of CXCR4-expressing astrocytes and microglia. Once glia are activated, they may initiate MAPK (mitogen-activated protein kinase) pathways, and subsequently produce proinflammatory cytokines and chemokines. Among them, CXCL12 could reinforce the astrocytic and microglial activation in autocrine and paracrine manners

  5. CXCR4-tropic HIV-1 suppresses replication of CCR5-tropic HIV-1 in human lymphoid tissue by selective induction of CC-chemokines.

    Science.gov (United States)

    Ito, Yoshinori; Grivel, Jean-Charles; Chen, Silvia; Kiselyeva, Yana; Reichelderfer, Patricia; Margolis, Leonid

    2004-02-01

    In infected individuals, human immunodeficiency virus type 1 (HIV-1) exist as a "swarm" of quasi species compartmentalized in tissues where individual viral variants may interact locally. We have used human lymphoid tissue, where the critical events of HIV disease occur, to study local interactions in model HIV-1 binary swarms ex vivo. We infected tissue blocks with binary mixtures consisting either of CCR5-dependent and CXCR4-dependent variants or of 2 dual-tropic HIV-1 variants, of which one is skewed to utilization of CXCR4 and the other of CCR5. HIV-1 variants that use CXCR4 suppress replication of CCR5-dependent HIV-1 variants, whereas CCR5-dependent HIV-1 variants do not affect replication of CXCR4-dependent HIV-1. CC-chemokines that inhibit replication of CCR5-dependent HIV-1 variants were up-regulated by CXCR4-dependent HIV-1, thus possibly contributing to this suppression. Tissue-specific chemokine/cytokine network modulations triggered by individual HIV-1 variants may be an important mechanism of local interactions among HIV-1 quasi species in infected tissue.

  6. Molecular cloning, characterization, and expression analysis of the CXCR4 gene from Turbot: Scophthalmus maximus.

    Science.gov (United States)

    Jia, Airong; Zhang, Xiao-Hua

    2009-01-01

    Chemokine receptor 4 (CXCR4) belongs to the large superfamily of G protein-coupled receptors. The EST sequence of CXCR4 from turbot (Scophthalmus maximus L.) was obtained from a subtractive cDNA library. In the present study, the full-length cDNA sequence of turbot CXCR4 was obtained, and sequence analysis indicated that its primary structure was highly similar to CXCR4 from other vertebrates. Quantitative real-time PCR demonstrated that the highest expression level of turbot CXCR4 was in the spleen following injection with physiological saline (PS). After turbot were challenged with Vibrio harveyi, the lowest expression level of CXCR4 was detected at 8 hours in the spleen and 12 hours in the head kidney, and then increased gradually to 36 hours. These findings suggested that CXCR4 may play a significant role in the immune response of turbot.

  7. Molecular Cloning, Characterization, and Expression Analysis of the CXCR4 Gene from Turbot: Scophthalmus maximus

    Directory of Open Access Journals (Sweden)

    Airong Jia

    2009-01-01

    Full Text Available Chemokine receptor 4 (CXCR4 belongs to the large superfamily of G protein-coupled receptors. The EST sequence of CXCR4 from turbot (Scophthalmus maximus L. was obtained from a subtractive cDNA library. In the present study, the full-length cDNA sequence of turbot CXCR4 was obtained, and sequence analysis indicated that its primary structure was highly similar to CXCR4 from other vertebrates. Quantitative real-time PCR demonstrated that the highest expression level of turbot CXCR4 was in the spleen following injection with physiological saline (PS. After turbot were challenged with Vibrio harveyi, the lowest expression level of CXCR4 was detected at 8 hours in the spleen and 12 hours in the head kidney, and then increased gradually to 36 hours. These findings suggested that CXCR4 may play a significant role in the immune response of turbot.

  8. Down-regulation of cell surface CXCR4 by HIV-1

    Directory of Open Access Journals (Sweden)

    Vigh Sandor

    2008-01-01

    Full Text Available Abstract Background CXC chemokine receptor 4 (CXCR4, a member of the G-protein-coupled chemokine receptor family, can serve as a co-receptor along with CD4 for entry into the cell of T-cell tropic X4 human immunodeficiency virus type 1 (HIV-1 strains. Productive infection of T-lymphoblastoid cells by X4 HIV-1 markedly reduces cell-surface expression of CD4, but whether or not the co-receptor CXCR4 is down-regulated has not been conclusively determined. Results Infection of human T-lymphoblastoid cell line RH9 with HIV-1 resulted in down-regulation of cell surface CXCR4 expression. Down-regulation of surface CXCR4 correlated temporally with the increase in HIV-1 protein expression. CXCR4 was concentrated in intracellular compartments in H9 cells after HIV-1 infection. Immunofluorescence microscopy studies showed that CXCR4 and HIV-1 glycoproteins were co-localized in HIV infected cells. Inducible expression of HIV-1 envelope glycoproteins also resulted in down-regulation of CXCR4 from the cell surface. Conclusion These results indicated that cell surface CXCR4 was reduced in HIV-1 infected cells, whereas expression of another membrane antigen, CD3, was unaffected. CXCR4 down-regulation may be due to intracellular sequestering of HIV glycoprotein/CXCR4 complexes.

  9. PEA3 activates CXCR4 transcription in MDA-MB-231 and MCF7 breast cancer cells

    Institute of Scientific and Technical Information of China (English)

    Shengmei Gu; Li Chen; Qi Hong; Tingting Yan; Zhigang Zhuang; Qiaoqiao wang; Wei Jin; Hua Zhu; Jiong Wu

    2011-01-01

    CXC chemokine receptor 4 (CXCR4) is a cell surface receptor that has been shown to mediate the metastasis of many solid tumors including lung,breast,kidney,and prostate tumors.In this study,we found that overexpression of ets variant gene 4 (PEA3) could elevate CXCR4 mRNA level and CXCR4 promoter activity in human MDA-MB-231 and MCF-7 breast cancer cells.PEA3 promoted CXCR4 expression and breast cancer metastasis.Chromatin immunoprecipitation assay demonstrated that PEA3 could bind to the CXCR4 promoter in the cells transfected with PEA3 expression vector.PEA3 siRNA attenuated CXCR4 promoter activity and the binding of PEA3 to the CXCR4 promoter in MDA-MB-231 and MCF-7 cells.These results indicated that PEA3 could activate CXCR4 promoter transcription and promote breast cancer metastasis.

  10. The CXCL12/CXCR4 axis promotes ligand-independent activation of the androgen receptor.

    Science.gov (United States)

    Kasina, Sathish; Macoska, Jill A

    2012-04-01

    The molecular mechanisms responsible for the transition of some prostate cancers from androgen ligand-dependent to androgen ligand-independent are incompletely established. Molecules that are ligands for G protein coupled receptors (GPCRs) have been implicated in ligand-independent androgen receptor (AR) activation. The purpose of this study was to examine whether CXCL12, the ligand for the GPCR, CXCR4, might mediate prostate cancer cell proliferation through AR-dependent mechanisms involving functional transactivation of the AR in the absence of androgen. The results of these studies showed that activation of the CXCL12/CXCR4 axis promoted: The nuclear accumulation of both wild-type and mutant AR in several prostate epithelial cell lines; AR-dependent proliferative responses; nuclear accumulation of the AR co-regulator SRC-1 protein; SRC-1:AR protein:protein association; co-localization of AR and SRC-1 on the promoters of AR-regulated genes; AR- and SRC-1 dependent transcription of AR-regulated genes; AR-dependent secretion of the AR-regulated PSA protein; P13K-dependent phosphorylation of AR; MAPK-dependent phosphorylation of SRC-1, and both MAPK- and P13K-dependent secretion of the PSA protein, in the absence of androgen. Taken together, these studies identify CXCL12 as a novel, non-steroidal growth factor that promotes the growth of prostate epithelial cells through AR-dependent mechanisms in the absence of steroid hormones. These findings support the development of novel therapeutics targeting the CXCL12/CXCR4 axis as an ancillary to those targeting the androgen/AR axis to effectively treat castration resistant/recurrent prostate tumors.

  11. Peptide-Functionalized Luminescent Iridium Complexes for Lifetime Imaging of CXCR4 Expression

    NARCIS (Netherlands)

    Kuil, J.; Steunenberg, P.; Chin, P.T.K.; Oldenburg, J.; Jalink, K.; Velders, A.H.; Leeuwen, F.W.B. van

    2011-01-01

    The chemokine receptor 4 (CXCR4) is over-expressed in 23 types of cancer in which it plays a role in, among others, the metastatic spread. For this reason it is a potential biomarker for the field of diagnostic oncology. The antagonistic Ac-TZ14011 peptide, which binds to CXCR4, has been conjugated

  12. The ligands of CXCR4 in vascularization

    OpenAIRE

    Tuchscheerer, Nancy

    2012-01-01

    The formation of a functional and integrated vascular network is a basic process in the growth and maintenance of tissues and can be established by two forms of blood vessel growth in adults: angiogenesis and arteriogenesis. In this study, the ligands of the chemokine receptor CXCR4 and its role in angiogenesis (represented by the experimental myocardial infarction) and arteriogenesis (represented by the murine hind limb ischemia model) was investigated. The first approach identified the CXCL...

  13. A novel approach to block HIV-1 coreceptor CXCR4 in non-toxic manner.

    Science.gov (United States)

    Liu, Ye; Zhou, Jieqiong; Pan, Ji-An; Mabiala, Prudence; Guo, Deyin

    2014-10-01

    The chemokine receptor CXCR4 is one of the major coreceptors for human immunodeficiency virus type 1 (HIV-1) and considered as an important therapeutic target. Knockdown of CXCR4 by RNA interference has emerged as a promising strategy for combating HIV-1 infection. However, there is a potential drawback to this strategy as undesired side effects may occur due to the loss of natural function of CXCR4. In this study, we developed a novel approach using a single lentiviral vector to express simultaneously CXCR4 dual-shRNAs and an shRNA-resistant CXCR4 mutant possessing the most possible natural functions of CXCR4 and reduced HIV-1 coreceptor activity. Via this approach we achieved the replacement of endogenous CXCR4 by CXCR4 mutant P191A that could compensate the functional loss of endogenous CXCR4 and significant reduction of HIV-1 replication by 59.2 %. Besides, we demonstrated that construction of recombinant lentiviral vector using 2A peptide-based strategy has significant advantages over using additional promoter-based strategy, including increase of lentivirus titer and avoidance of promoter competition. Therefore, the novel approach to block HIV-1 coreceptor CXCR4 without impairing its normal function provides a new strategy for CXCR4-targeted therapeutics for HIV-1 infection and potential universal applications to knock down a cellular protein in non-toxic manner.

  14. Metal ion enhanced binding of AMD3100 to Asp262 in the CXCR4 receptor

    DEFF Research Database (Denmark)

    Gerlach, Lars Ole; Jakobsen, Janus S; Jensen, Kasper P;

    2003-01-01

    +), Zn(2+), or Ni(2+) into the cyclam rings of the compound. The rank order of the transition metal ions correlated with the calculated binding energy between free acetate and the metal ions coordinated in a cyclam ring. Construction of AMD3100 substituted with only a single Cu(2+) or Ni(2+) ion...... demonstrated that the increase in binding affinity of the metal ion substituted bicyclam is achieved through an enhanced interaction of just one of the ring systems. Mutational analysis of potential metal ion binding residues in the main ligand binding crevice of the CXCR4 receptor showed that although binding...... of the bicyclam is dependent on both Asp(171) and Asp(262), the enhancing effect of the metal ion was selectively eliminated by substitution of Asp(262) located at the extracellular end of TM-VI. It is concluded that the increased binding affinity of the metal ion substituted AMD3100 is obtained through enhanced...

  15. Immunohistochemical Expression of CXCR4 on Breast Cancer and Its Clinical Significance

    Directory of Open Access Journals (Sweden)

    Marina Okuyama Kishima

    2015-01-01

    Full Text Available Many tumor cells express chemokines and chemokine receptors, and, for this reason, these molecules can affect the tumor progression. It is known that breast cancer is a complex and heterogeneous neoplasia comprising distinct diseases, histological characteristics, and clinical outcomes. The most studied role for CXCL12 chemokine and its receptor CXCR4 in breast cancer pathogenesis is the metastasis event, although several reports have demonstrated its involvement in other processes, such as angiogenesis and tumor growth. It has been found that CXCR4 is required for breast cancer cell migration to other sites such as lung, bone, and lymph nodes, which express high levels of CXCL12 chemokine. Therefore, CXCR4 is being considered a prognostic marker in breast cancer. Within this context, this review summarizes established studies involving expression of CXCR4 on breast cancer, focusing on its clinical significance.

  16. The amino-terminal domain of the CCR2 chemokine receptor acts as coreceptor for HIV-1 infection

    OpenAIRE

    1997-01-01

    The chemokines are a homologous serum protein family characterized by their ability to induce activation of integrin adhesion molecules and leukocyte migration. Chemokines interact with their receptors, which are composed of a single-chain, seven-helix, membrane-spanning protein coupled to G proteins. Two CC chemokine receptors, CCR3 and CCR5, as well as the CXCR4 chemokine receptor, have been shown necessary for infection by several HIV-1 virus isolates. We studied the effect of the chemokin...

  17. Hypoxia increases the metastatic ability of breast cancer cells via upregulation of CXCR4

    LENUS (Irish Health Repository)

    Cronin, Patricia A

    2010-05-21

    Abstract Background Chemokine SDF1α and its unique receptor CXCR4 have been implicated in organ-specific metastases of many cancers including breast cancer. Hypoxia is a common feature of solid tumors and is associated with their malignant phenotype. We hypothesized that hypoxia would upregulate CXCR4 expression and lead to increased chemotactic responsiveness to its specific ligand SDF1α. Methods Three breast cancer cell lines MDA-MB-231, MCF7 and 4T1 were subjected to 48 hrs of hypoxia or normoxia. Cell surface receptor expression was evaluated using flow cytometry. An extracellular matrix invasion assay and microporous migration assay was used to assess chemotactic response and metastatic ability. Results CXCR4 surface expression was significantly increased in the two human breast cancer cell lines, MDA-MB-231 and MCF7, following exposure to hypoxia. This upregulation of CXCR4 cell surface expression corresponded to a significant increase in migration and invasion in response to SDF1-α in vitro. The increase in metastatic potential of both the normoxic and the hypoxic treated breast cancer cell lines was attenuated by neutralization of CXCR4 with a CXCR4 neutralizing mAb, MAB172 or a CXCR4 antagonist, AMD3100, showing the relationship between CXCR4 overexpression and increased chemotactic responsiveness. Conclusions CXCR4 expression can be modulated by the tissue microenvironment such as hypoxia. Upregulation of CXCR4 is associated with increased migratory and invasive potential and this effect can be abrogated by CXCR4 inhibition. Chemokine receptor CXCR4 is a potential therapeutic target in the adjuvant treatment of breast cancer.

  18. Interaction between CXCR4 and CCL20 pathways regulates tumor growth.

    Directory of Open Access Journals (Sweden)

    Katia Beider

    Full Text Available The chemokine receptor CXCR4 and its ligand CXCL12 is overexpressed in the majority of tumors and is critically involved in the development and metastasis of these tumors. CXCR4 is expressed in malignant tumor cells whereas its ligand SDF-1 (CXCL12 is expressed mainly by cancer associated fibroblasts (CAF. Similarly to CXCR4, the chemokine CCL20 is overexpressed in variety of tumors; however its role and regulation in tumors is not fully clear. Here, we show that the chemokine receptor CXCR4 stimulates the production of the chemokine CCL20 and that CCL20 stimulates the proliferation and adhesion to collagen of various tumor cells. Furthermore, overexpression of CCL20 in tumor cells promotes growth and adhesion in vitro and increased tumor growth and invasiveness in vivo. Moreover, neutralizing antibodies to CCL20 inhibit the in vivo growth of tumors that either overexpress CXCR4 or CCL20 or naturally express CCL20. These results reveal a role for CCL20 in CXCR4-dependent and -independent tumor growth and suggest a therapeutic potential for CCL20 and CCR6 antagonists in the treatment of CXCR4- and CCL20-dependent malignancies.

  19. Interaction between CXCR4 and CCL20 pathways regulates tumor growth.

    Science.gov (United States)

    Beider, Katia; Abraham, Michal; Begin, Michal; Wald, Hanna; Weiss, Ido D; Wald, Ori; Pikarsky, Eli; Abramovitch, Rinat; Zeira, Evelyne; Galun, Eithan; Nagler, Arnon; Peled, Amnon

    2009-01-01

    The chemokine receptor CXCR4 and its ligand CXCL12 is overexpressed in the majority of tumors and is critically involved in the development and metastasis of these tumors. CXCR4 is expressed in malignant tumor cells whereas its ligand SDF-1 (CXCL12) is expressed mainly by cancer associated fibroblasts (CAF). Similarly to CXCR4, the chemokine CCL20 is overexpressed in variety of tumors; however its role and regulation in tumors is not fully clear. Here, we show that the chemokine receptor CXCR4 stimulates the production of the chemokine CCL20 and that CCL20 stimulates the proliferation and adhesion to collagen of various tumor cells. Furthermore, overexpression of CCL20 in tumor cells promotes growth and adhesion in vitro and increased tumor growth and invasiveness in vivo. Moreover, neutralizing antibodies to CCL20 inhibit the in vivo growth of tumors that either overexpress CXCR4 or CCL20 or naturally express CCL20. These results reveal a role for CCL20 in CXCR4-dependent and -independent tumor growth and suggest a therapeutic potential for CCL20 and CCR6 antagonists in the treatment of CXCR4- and CCL20-dependent malignancies.

  20. Chemokine receptor expression on the surface of peripheral blood mononuclear cells in Chagas disease.

    Science.gov (United States)

    Talvani, Andre; Rocha, Manoel O C; Ribeiro, Antonio L; Correa-Oliveira, Rodrigo; Teixeira, Mauro M

    2004-01-15

    We evaluated the expression of chemokine receptors (CCR1, CCR2, CCR5, and CXCR4) on the surface of peripheral blood mononuclear cells obtained from patients with chronic chagasic cardiomyopathy (CCC) and noninfected individuals. Only CCR5 and CXCR4 expression was different on the surface of the subsets (CD4, CD8, and CD14) evaluated. Patients with mild CCC had elevated leukocyte expression of CCR5, compared with noninfected individuals or those with severe disease. CXCR4 expression was lower on leukocytes from patients with severe CCC. The differential expression of both receptors on leukocytes of patients with CCC was consistent and clearly correlated with the degree of heart function such that the lower the heart function, the lower the expression of either CCR5 or CXCR4. These results highlight the possible participation of the chemokine system in early forms of chagasic cardiomyopathy and the relevance of heart failure-induced remodeling in modifying immune parameters in infected individuals.

  1. Development of a unique small molecule modulator of CXCR4.

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    Zhongxing Liang

    Full Text Available BACKGROUND: Metastasis, the spread and growth of tumor cells to distant organ sites, represents the most devastating attribute and plays a major role in the morbidity and mortality of cancer. Inflammation is crucial for malignant tumor transformation and survival. Thus, blocking inflammation is expected to serve as an effective cancer treatment. Among anti-inflammation therapies, chemokine modulation is now beginning to emerge from the pipeline. CXC chemokine receptor-4 (CXCR4 and its ligand stromal cell-derived factor-1 (CXCL12 interaction and the resulting cell signaling cascade have emerged as highly relevant targets since they play pleiotropic roles in metastatic progression. The unique function of CXCR4 is to promote the homing of tumor cells to their microenvironment at the distant organ sites. METHODOLOGY/PRINCIPAL FINDINGS: We describe the actions of N,N'-(1,4-phenylenebis(methylenedipyrimidin-2-amine (designated MSX-122, a novel small molecule and partial CXCR4 antagonist with properties quite unlike that of any other reported CXCR4 antagonists, which was prepared in a single chemical step using a reductive amination reaction. Its specificity toward CXCR4 was tested in a binding affinity assay and a ligand competition assay using (18F-labeled MSX-122. The potency of the compound was determined in two functional assays, Matrigel invasion assay and cAMP modulation. The therapeutic potential of MSX-122 was evaluated in three different murine models for inflammation including an experimental colitis, carrageenan induced paw edema, and bleomycin induced lung fibrosis and three different animal models for metastasis including breast cancer micrometastasis in lung, head and neck cancer metastasis in lung, and uveal melanoma micrometastasis in liver in which CXCR4 was reported to play crucial roles. CONCLUSIONS/SIGNIFICANCE: We developed a novel small molecule, MSX-122, that is a partial CXCR4 antagonist without mobilizing stem cells, which can

  2. Humoral Immune Pressure Selects for HIV-1 CXC-chemokine Receptor 4-using Variants

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    Nina Lin

    2016-06-01

    Full Text Available Although both C-C chemokine receptor 5 (CCR5- and CXC chemokine receptor 4 (CXCR4-using HIV-1 strains cause AIDS, the emergence of CXCR4-utilizing variants is associated with an accelerated decline in CD4+ T cells. It remains uncertain if CXCR4-using viruses hasten disease or if these variants only emerge after profound immunological damage. We show that exclusively CXCR4- as compared to cocirculating CCR5-utilizing variants are less sensitive to neutralization by both contemporaneous autologous plasma and plasma pools from individuals that harbor only CCR5-using HIV-1. The CXCR4-utilizing variants, however, do not have a global antigenic change because they remain equivalently susceptible to antibodies that do not target coreceptor binding domains. Studies with envelope V3 loop directed antibodies and chimeric envelopes suggest that the neutralization susceptibility differences are potentially influenced by the V3 loop. In vitro passage of a neutralization sensitive CCR5-using virus in the presence of autologous plasma and activated CD4+ T cells led to the emergence of a CXCR4-utilizing virus in 1 of 3 cases. These results suggest that in some but not necessarily all HIV-1 infected individuals humoral immune pressure against the autologous virus selects for CXCR4-using variants, which potentially accelerates disease progression. Our observations have implications for using antibodies for HIV-1 immune therapy.

  3. Humoral Immune Pressure Selects for HIV-1 CXC-chemokine Receptor 4-using Variants.

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    Lin, Nina; Gonzalez, Oscar A; Registre, Ludy; Becerril, Carlos; Etemad, Behzad; Lu, Hong; Wu, Xueling; Lockman, Shahin; Essex, Myron; Moyo, Sikhulile; Kuritzkes, Daniel R; Sagar, Manish

    2016-06-01

    Although both C-C chemokine receptor 5 (CCR5)- and CXC chemokine receptor 4 (CXCR4)-using HIV-1 strains cause AIDS, the emergence of CXCR4-utilizing variants is associated with an accelerated decline in CD4+ T cells. It remains uncertain if CXCR4-using viruses hasten disease or if these variants only emerge after profound immunological damage. We show that exclusively CXCR4- as compared to cocirculating CCR5-utilizing variants are less sensitive to neutralization by both contemporaneous autologous plasma and plasma pools from individuals that harbor only CCR5-using HIV-1. The CXCR4-utilizing variants, however, do not have a global antigenic change because they remain equivalently susceptible to antibodies that do not target coreceptor binding domains. Studies with envelope V3 loop directed antibodies and chimeric envelopes suggest that the neutralization susceptibility differences are potentially influenced by the V3 loop. In vitro passage of a neutralization sensitive CCR5-using virus in the presence of autologous plasma and activated CD4+ T cells led to the emergence of a CXCR4-utilizing virus in 1 of 3 cases. These results suggest that in some but not necessarily all HIV-1 infected individuals humoral immune pressure against the autologous virus selects for CXCR4-using variants, which potentially accelerates disease progression. Our observations have implications for using antibodies for HIV-1 immune therapy.

  4. Chemokines and Chemokine Receptors in Multiple Sclerosis

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    Wenjing Cheng

    2014-01-01

    Full Text Available Multiple sclerosis is an autoimmune disease with classical traits of demyelination, axonal damage, and neurodegeneration. The migration of autoimmune T cells and macrophages from blood to central nervous system as well as the destruction of blood brain barrier are thought to be the major processes in the development of this disease. Chemokines, which are small peptide mediators, can attract pathogenic cells to the sites of inflammation. Each helper T cell subset expresses different chemokine receptors so as to exert their different functions in the pathogenesis of MS. Recently published results have shown that the levels of some chemokines and chemokine receptors are increased in blood and cerebrospinal fluid of MS patients. This review describes the advanced researches on the role of chemokines and chemokine receptors in the development of MS and discusses the potential therapy of this disease targeting the chemokine network.

  5. The HIV-1 Gp120/CXCR4 Axis Promotes CCR7 Ligand-Dependent CD4 T Cell Migration: CCR7 Homo- and CCR7/CXCR4 Hetero-Oligomer Formation as a Possible Mechanism for Up-Regulation of Functional CCR7

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    Haruko Hayasaka; Daichi Kobayashi; Hiromi Yoshimura; Nakayama, Emi E.; Tatsuo Shioda; Masayuki Miyasaka

    2015-01-01

    During human immunodeficiency virus (HIV) infection, enhanced migration of infected cells to lymph nodes leads to efficient propagation of HIV-1. The selective chemokine receptors, including CXCR4 and CCR7, may play a role in this process, yet the viral factors regulating chemokine-dependent T cell migration remain relatively unclear. The functional cooperation between the CXCR4 ligand chemokine CXCL12 and the CCR7 ligand chemokines CCL19 and CCL21 enhances CCR7-dependent T cell motility in v...

  6. CXCR4 expression in feline mammary carcinoma cells: evidence of a proliferative role for the SDF-1/CXCR4 axis

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    Ferrari Angelo

    2012-03-01

    Full Text Available Abstract Background Mammary tumours frequently develop in female domestic cats being highly malignant in a large percentage of cases. Chemokines regulate many physiological and pathological processes including organogenesis, chemotaxis of inflammatory cells, as well as tumour progression and metastasization. In particular, the chemokine/receptor pair SDF-1/CXCR4 has been involved in the regulation of metastatic potential of neoplastic cells, including breast cancer. The aim of this study was the immunohistochemical defininition of the expression profile of CXCR4 in primary and metastatic feline mammary carcinomas and the evaluation of the role of SDF-1 in feline mammary tumour cell proliferation. Results A total of 45 mammary surgical samples, including 33 primary tumours (31 carcinomas and 2 adenomas, 6 metastases, and 4 normal mammary tissues were anlyzed. Tumor samples were collected from a total number of 26 animals, as in some cases concurrent occurrence of neoplasm in more than one mammary gland was observed. Tissues were processed for standard histological examination, and all lesions were classified according to the World Health Organization criteria. CXCR4 expression in neoplastic cells was evaluated by immunohistochemistry. The level of CXCR4 immunoreactivity was semi-quantitatively estimated as CXCR4 score evaluating both the number of positive cells and the intensity of staining. Six primary, fibroblast-free primary cultures were obtained from fresh feline mammary carcinomas and characterized by immunofluorescence for CXCR4 and malignant mammary cell marker expression. SDF-1-dependent in vitro proliferative effects were also assayed. CXCR4 expression was observed in 29 out of 31 malignant tissues with a higher CXCR4 score observed in 4 out of 6 metastatic lesions than in the respective primary tumours. In 2 benign lesions analyzed, only the single basaloid adenoma showed a mild positive immunostaining against CXCR4. Normal tissue did

  7. Role of C-X-C chemokine ligand 12/C-X-C chemokine receptor 4 in the progression of hepatocellular carcinoma.

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    Jeng, Kuo-Shyang; Jeng, Chi-Juei; Jeng, Wen-Juei; Chang, Chiung-Fang; Sheen, I-Shyan

    2017-08-01

    The efficacy of the current non-surgical treatments for advanced hepatocellular carcinoma (HCC) remains limited and novel treatments are required to improve patient outcomes. The majority of HCCs develop from chronically damaged tissue that contains a high degree of inflammation and fibrosis, which promotes tumor progression and resistance to therapy. Understanding the interaction between stromal components and cancer cells (and the signaling pathways involved in this interaction) could aid the identification of novel therapeutic targets. Numerous studies have demonstrated a marked association between high C-X-C chemokine receptor 4 (CXCR4) expression and the invasiveness, progression and metastasis of HCC. The present review will investigate the different roles of CXCR4 in the progression of HCC and discuss possible future treatments. Through the C-X-C chemokine ligand 12 (CXCL12)/CXCR4 signaling pathway, ephrin A1 activation enhances the migration of endothelial progenitor cells to HCC to enable the neovascularization of tumors. There is an association between nuclear CXCR4 expression and the lymph node metastasis of HCC to distant areas. CXCR4 enhances cell migration in vitro and cell homing in vivo. CXCR4 levels are concentrated at the border of a tumor and in perivascular areas, inducing invasive behavior. The binding of CXCL12 to CXCR4 activates intracellular signaling pathways and induces crosstalk with transforming growth factor-β signaling, which enhances the migration of cancer cells. The CXCL12/CXCR4 axis also activates expression of matrix metalloproteinase 10, which further stimulates migration. CXCR4 is likely to crosstalk with the sonic hedgehog signaling pathway, contributing to tumor invasiveness and supporting the cancer stem-cell population; as a result, CXCR4 can be regarded as a cancer stem-cell marker. CXCR4 influences interstitial fluid flow-induced invasion. CXCR4 expression and HCC cell migration are promoted by α-fetoprotein, which

  8. Coexpression of EGFR and CXCR4 predicts poor prognosis in resected pancreatic ductal adenocarcinoma.

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    Huanwen Wu

    Full Text Available Epidermal growth factor receptor (EGFR is highly expressed in pancreatic ductal adenocarcinoma (PDAC and is involved in tumorigenesis and development. However, EGFR expression alone has limited clinical and prognostic significance. Recently, the cross-talk between EGFR and G-protein-coupled chemokine receptor CXCR4 has become increasingly recognized.In the present study, immunohistochemical staining of EGFR and CXCR4 was performed on paraffin-embedded specimens from 131 patients with surgically resected PDAC. Subsequently, the associations between EGFR expression, CXCR4 expression, EGFR/CXCR4 coexpression and clinicopathologic factors were assessed, and survival analyses were performed.In total, 64 (48.9% patients expressed EGFR, 68 (51.9% expressed CXCR4, and 33 (25.2% coexpressed EGFR and CXCR4. No significant association between EGFR and CXCR4 expression was observed (P = 0.938. EGFR expression significantly correlated with tumor differentiation (P = 0.031, whereas CXCR4 expression significantly correlated with lymph node metastasis (P = 0.001. EGFR/CXCR4 coexpression was significantly associated with lymph node metastasis (P = 0.026, TNM stage (P = 0.048, and poor tumor differentiation (P = 0.004. By univariate survival analysis, both CXCR4 expression and EGFR/CXCR4 coexpression were significant prognostic factors for poor disease-free survival (DFS and overall survival (OS. Moreover, EGFR/CXCR4 coexpression significantly increased the hazard ratio for both recurrence and death compared with EGFR or CXCR4 protein expression alone. Multivariate survival analysis demonstrated that EGFR/CXCR4 coexpression was an independent prognostic factor for DFS (HR = 2.33, P<0.001 and OS (HR = 2.48, P = 0.001.In conclusion, our data indicate that although EGFR expression alone has limited clinical and prognostic significance, EGFR/CXCR4 coexpression identified a subset of PDAC patients with more aggressive tumor characteristics and a significantly worse

  9. Disclosing the CXCR4 expression in lymphoproliferative diseases by targeted molecular imaging.

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    Wester, Hans Jürgen; Keller, Ulrich; Schottelius, Margret; Beer, Ambros; Philipp-Abbrederis, Kathrin; Hoffmann, Frauke; Šimeček, Jakub; Gerngross, Carlos; Lassmann, Michael; Herrmann, Ken; Pellegata, Natalia; Rudelius, Martina; Kessler, Horst; Schwaiger, Markus

    2015-01-01

    Chemokine ligand-receptor interactions play a pivotal role in cell attraction and cellular trafficking, both in normal tissue homeostasis and in disease. In cancer, chemokine receptor-4 (CXCR4) expression is an adverse prognostic factor. Early clinical studies suggest that targeting CXCR4 with suitable high-affinity antagonists might be a novel means for therapy. In addition to the preclinical evaluation of [(68)Ga]Pentixafor in mice bearing human lymphoma xenografts as an exemplary CXCR4-expressing tumor entity, we report on the first clinical applications of [(68)Ga]Pentixafor-Positron Emission Tomography as a powerful method for CXCR4 imaging in cancer patients. [(68)Ga]Pentixafor binds with high affinity and selectivity to human CXCR4 and exhibits a favorable dosimetry. [(68)Ga]Pentixafor-PET provides images with excellent specificity and contrast. This non-invasive imaging technology for quantitative assessment of CXCR4 expression allows to further elucidate the role of CXCR4/CXCL12 ligand interaction in the pathogenesis and treatment of cancer, cardiovascular diseases and autoimmune and inflammatory disorders.

  10. Chemokine Receptors and Transplantation

    Institute of Scientific and Technical Information of China (English)

    Jinquan Tan; Gang Zhou

    2005-01-01

    A complex process including both the innate and acquired immune responses results in allograft rejection. Some chemokine receptors and their ligands play essential roles not only for leukocyte migration into the graft but also in facilitating dendritic and T cell trafficking between lymph nodes and the transplant in the early and late stage of the allogeneic response. This review focuses on the impact of these chemoattractant proteins on transplant outcome and novel diagnostic and therapeutic approaches for antirejection therapy based on targeting of chemokine receptors and/or their ligands. Cellular & Molecular Immunology.

  11. The maintenance of cisplatin- and paclitaxel-induced mechanical and cold allodynia is suppressed by cannabinoid CB2 receptor activation and independent of CXCR4 signaling in models of chemotherapy-induced peripheral neuropathy

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    Deng Liting

    2012-09-01

    Full Text Available Abstract Background Chemotherapeutic agents produce dose-limiting peripheral neuropathy through mechanisms that remain poorly understood. We previously showed that AM1710, a cannabilactone CB2 agonist, produces antinociception without producing central nervous system (CNS-associated side effects. The present study was conducted to examine the antinociceptive effect of AM1710 in rodent models of neuropathic pain evoked by diverse chemotherapeutic agents (cisplatin and paclitaxel. A secondary objective was to investigate the potential contribution of alpha-chemokine receptor (CXCR4 signaling to both chemotherapy-induced neuropathy and CB2 agonist efficacy. Results AM1710 (0.1, 1 or 5 mg/kg i.p. suppressed the maintenance of mechanical and cold allodynia in the cisplatin and paclitaxel models. Anti-allodynic effects of AM1710 were blocked by the CB2 antagonist AM630 (3 mg/kg i.p., but not the CB1 antagonist AM251 (3 mg/kg i.p., consistent with a CB2-mediated effect. By contrast, blockade of CXCR4 signaling with its receptor antagonist AMD3100 (10 mg/kg i.p. failed to attenuate mechanical or cold hypersensitivity induced by either cisplatin or paclitaxel. Moreover, blockade of CXCR4 signaling failed to alter the anti-allodynic effects of AM1710 in the paclitaxel model, further suggesting distinct mechanisms of action. Conclusions Our results indicate that activation of cannabinoid CB2 receptors by AM1710 suppresses both mechanical and cold allodynia in two distinct models of chemotherapy-induced neuropathic pain. By contrast, CXCR4 signaling does not contribute to the maintenance of chemotherapy-induced established neuropathy or efficacy of AM1710. Our studies suggest that CB2 receptors represent a promising therapeutic target for the treatment of toxic neuropathies produced by cisplatin and paclitaxel chemotherapeutic agents.

  12. CXCR4 and CCR7: Two eligible targets in targeted cancer therapy.

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    Mishan, Mohammad Amir; Ahmadiankia, Naghmeh; Bahrami, Ahmad Reza

    2016-09-01

    Cancer is one of the most common cause of death in the world with high negative emotional, economic, and social impacts. Conventional therapeutic methods, including chemotherapy and radiotherapy, have not proven satisfactory and relapse is common in most cases. Recent studies have focused on targeted therapy with more precise identification and targeted attacks to the cancer cells. For this purpose, chemokine receptors are proper targets and among them, CXCR4 and CCR7, with a crucial role in cancer metastasis, are being considered as desired candidates for investigation. In this review paper, the most important experimental results are highlighted on the potential targeted therapies based on CXCR4 and CCR7 chemokine receptors.

  13. Discovery and Characterization of an Endogenous CXCR4 Antagonist

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    Onofrio Zirafi

    2015-05-01

    Full Text Available CXCL12-CXCR4 signaling controls multiple physiological processes and its dysregulation is associated with cancers and inflammatory diseases. To discover as-yet-unknown endogenous ligands of CXCR4, we screened a blood-derived peptide library for inhibitors of CXCR4-tropic HIV-1 strains. This approach identified a 16 amino acid fragment of serum albumin as an effective and highly specific CXCR4 antagonist. The endogenous peptide, termed EPI-X4, is evolutionarily conserved and generated from the highly abundant albumin precursor by pH-regulated proteases. EPI-X4 forms an unusual lasso-like structure and antagonizes CXCL12-induced tumor cell migration, mobilizes stem cells, and suppresses inflammatory responses in mice. Furthermore, the peptide is abundant in the urine of patients with inflammatory kidney diseases and may serve as a biomarker. Our results identify EPI-X4 as a key regulator of CXCR4 signaling and introduce proteolysis of an abundant precursor protein as an alternative concept for chemokine receptor regulation.

  14. Prognostic value of CXCL12 and CXCR4 in inoperable head and neck squamous cell carcinoma

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    Rave-Fraenk, Margret; Tehrany, Narges; Leu, Martin; Weber, Hanne Elisabeth; Wolff, Hendrik Andreas [University Medical Center Goettingen, Department of Radiotherapy and Radiation Oncology, Goettingen (Germany); Kitz, Julia [University Medical Center Goettingen, Department of Pathology, Goettingen (Germany); Burfeind, Peter [University Medical Center Goettingen, Department of Human Genetics, Goettingen (Germany); Schliephake, Henning [University Medical Center Goettingen, Department of Oral and Maxillofacial Surgery, Goettingen (Germany); Canis, Martin [University Medical Center Goettingen, Department of Otorhinolaryngology, Head and Neck Surgery, Goettingen (Germany); Beissbarth, Tim [University Medical Center Goettingen, Institute of Medical Statistics, Goettingen (Germany); Reichardt, Holger Michael [University Medical Center Goettingen, Institute for Cellular and Molecular Immunology, Goettingen (Germany)

    2016-01-15

    The chemokine CXCL12 and its receptor CXCR4 can affect tumor growth, recurrence, and metastasis. We tested the hypothesis that the CXCL12 and CXCR4 expression influences the prognosis of patients with inoperable head and neck cancer treated with definite radiotherapy or chemoradiotherapy. Formalin-fixed paraffin-embedded pretreatment tumor tissue from 233 patients with known HPV/p16{sup INK4A} status was analyzed. CXCL12 and CXCR4 expressions were correlated with pretreatment parameters and survival data by univariate and multivariate Cox regression. CXCL12 was expressed in 43.3 % and CXCR4 in 66.1 % of the samples and both were correlated with HPV/p16{sup INK4A} positivity. A high CXCL12 expression was associated with increased overall survival (p = 0.036), while a high CXCR4 expression was associated with decreased metastasis-free survival (p = 0.034). A high CXCR4 expression could be regarded as a negative prognostic factor in head and neck cancer because it may foster metastatic spread. This may recommend CXCR4 as therapeutic target for combating head and neck cancer metastasis. (orig.) [German] Das Chemokin CXCL12 und sein Rezeptor CXCR4 beeinflussen Tumorwachstum, Auftreten von Rezidiven und Metastasierung. Es wurde die Hypothese geprueft, dass ein Zusammenhang der CXCL12- und CXCR4-Expression mit der Prognose von Patienten bestehe, die wegen eines inoperablen Kopf-Hals-Tumors eine primaere Radio- oder Radiochemotherapie erhielten. Dabei wurde auch der HPV-Status der Patienten beruecksichtigt. Formalinfixierte Proben aus unbehandelten Tumoren von 233 Patienten mit bekanntem HPV/p16{sup INK4A}-Status wurden ausgewertet. Die CXCL12- und CXCR4-Expression wurde mit klinischen Parametern und Ueberlebensdaten mittels uni- und multivariater Cox Regression analysiert. CXCL12 wurde von 43,3 %, CXCR4 von 66,1 % der Tumoren exprimiert, und beide Marker korrelierten mit einer HPV/p16{sup INK4A}-Expression. Eine hohe CXCL12-Expression war mit einem verbesserten

  15. EGFR expression is associated with cytoplasmic staining of CXCR4 and predicts poor prognosis in triple-negative breast carcinomas.

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    Li, Rong-Hui; Huang, Wen-He; Wu, Jun-Dong; Du, Cai-Wen; Zhang, Guo-Jun

    2017-02-01

    The purpose of the present study was to investigate the significance of C-X-C motif chemokine receptor type 4 (CXCR4) and epidermal growth factor receptors (EGFRs) in triple-negative breast cancer (TNBC). CXCR4 and EGFR expression levels were immunohistochemically determined in 207 primary breast cancer specimens. The associations between receptor expression and clinicopathological characteristics were analyzed, and receptor expression was also assessed as a prognostic factor. In the human MDA-MB-231 TNBC cell line, CXCR4 or EGFR was stably knocked down by short hairpin RNA, and the biological behavior of the cells, including migration, invasion and tumorigenesis, was investigated. The results revealed that TNBC was associated with younger age, higher histological grade and an aggressive phenotype. CXCR4 and EGFR were highly expressed in patients with TNBC, and those with high CXCR4 or EGFR expression exhibited an unfavorable prognosis in terms of disease-free survival and overall survival. In MDA-MB-231 cells, the expression of CXCR4 protein was decreased following EGFR silencing, while CXCR4 knockdown also caused a decrease in EGFR protein levels. The migratory and invasive capabilities of MDA-MB-231 cells were decreased following the knockdown of CXCR4 or EGFR expression. A strong correlation between CXCR4 and EGFR expression was identified in patients with TNBC. The results suggest that elevated expression levels of these two receptors may serve as predictive factors for poor prognosis in patients with TNBC. In addition, tumor proliferation, migration, invasion and tumorigenesis are weakened in MDA-MB-231 cells following suppression of CXCR4 or EGFR expression. Therefore, EGFR and CXCR4 may be potential therapeutic targets for TNBC.

  16. Interfering with CXCR4 expression inhibits proliferation, adhesion and migration of breast cancer MDA-MB-231 cells.

    Science.gov (United States)

    Guo, Shanyu; Xiao, Dan; Liu, Huihui; Zheng, Xiao; Liu, Lei; Liu, Shougui

    2014-10-01

    To investigate the effect and mechanism of the CXC chemokine receptor 4 (CXCR4) in the proliferation and migration of breast cancer, a short-hairpin RNA (shRNA) eukaryotic expression vector targeting CXCR4 was constructed, and the impact of such on the proliferation, adhesion and migration of human breast cancer MDA-MB-231 cells was observed. The fragments of CXCR4-shRNA were synthesized and cloned into a pGCsi-U6-Neo-green fluorescent protein vector. The recombinant plasmids were transfected into 293T cells and the most efficacious interfering vector was selected. MDA-MB-231 cells were transfected by liposome assay. The effects of silencing CXCR4 expression by shRNA on the growth, adhesion and migration of MDA-MB-231 cells were determined by Cell Counting Kit-8, cell-matrix adhesion and wound-healing assays. The shRNA eukaryotic expression vectors targeting CXCR4 (CXCR4-shRNA) were successfully constructed and transfected into 293T cells. Quantitative polymerase chain reaction and western blot analysis revealed that the maximum inhibitory rate of CXCR4 expression was 81.3%. CXCR4-shRNA transfection significantly inhibited the proliferation of MDA-MB-231 cells (PMB-231 cells and the extracellular matrix (PMB-231 cells in the CXCR4-shRNA transfection group was significantly smaller than that in the control plasmid and blank control groups (PMB-231 cells.

  17. Discovery and computer aided potency optimization of a novel class of small molecule CXCR4 antagonists.

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    Victoria Vinader

    Full Text Available Amongst the chemokine signalling axes involved in cancer, chemokine CXCL12 acting on chemokine receptor CXCR4 is particularly significant since it orchestrates migration of cancer cells in a tissue-specific metastatic process. High CXCR4 tumour expression is associated with poor prognosis of lung, brain, CNS, blood and breast cancers. We have identified a new class of small molecule CXCR4 antagonists based on the use of computational modelling studies in concert with experimental determination of in vitro activity against CXCL12-induced intracellular calcium mobilisation, proliferation and chemotaxis. Molecular modelling proved to be a useful tool in rationalising our observed potencies, as well as informing the direction of the synthetic efforts aimed at producing more potent compounds.

  18. CXCR7 maintains osteosarcoma invasion after CXCR4 suppression in bone marrow microenvironment.

    Science.gov (United States)

    Han, Yan; Wu, Chunlei; Wang, Jing; Liu, Na

    2017-05-01

    The major cause of death in osteosarcoma is the invasion and metastasis. Better understanding of the molecular mechanism of osteosarcoma invasion is essential in developing effective tumor-suppressive therapies. Interaction between chemokine receptors plays a crucial role in regulating osteosarcoma invasion. Here, we investigated the relationship between CXCR7 and CXCR4 in osteosarcoma invasion induced by bone marrow microenvironment. Human bone marrow mesenchymal stem cells were co-cultured with osteosarcoma cells to mimic actual bone marrow microenvironment. Osteosarcoma cell invasion and CXCL12/CXCR4 activation were observed within this co-culture model. Interestingly, in this co-culture model, osteosarcoma cell invasion was not inhibited by suppressing CXCR4 expression with neutralizing antibody or specific inhibitor AMD3100. Downstream signaling extracellular signal-regulated kinase and signal transducer and activator of transcription 3 were not significantly affected by CXCR4 inhibition. However, suppressing CXCR4 led to CXCR7 upregulation. Constitutive expression of CXCR7 could maintain osteosarcoma cell invasion when CXCR4 was suppressed. Simultaneously, inhibiting CXCR4 and CXCR7 compromised osteosarcoma invasion in co-culture system and suppressed extracellular signal-regulated kinase and signal transducer and activator of transcription 3 signals. Moreover, bone marrow microenvironment, not CXCL12 alone, is required for CXCR7 activation after CXCR4 suppression. Taken together, suppressing CXCR4 is not enough to impede osteosarcoma invasion in bone marrow microenvironment since CXCR7 is activated to sustain invasion. Therefore, inhibiting both CXCR4 and CXCR7 could be a promising strategy in controlling osteosarcoma invasion.

  19. Preclinical development of a novel class of CXCR4 antagonist impairing solid tumors growth and metastases.

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    Luigi Portella

    Full Text Available The CXCR4/CXCL12 axis plays a role in cancer metastases, stem cell mobilization and chemosensitization. Proof of concept for efficient CXCR4 inhibition has been demonstrated in stem cell mobilization prior to autologous transplantation in hematological malignancies. Nevertheless CXCR4 inhibitors suitable for prolonged use as required for anticancer therapy are not available. To develop new CXCR4 antagonists a rational, ligand-based approach was taken, distinct from the more commonly used development strategy. A three amino acid motif (Ar-Ar-X in CXCL12, also found in the reverse orientation (X-Ar-Ar in the vMIP-II inhibitory chemokine formed the core of nineteen cyclic peptides evaluated for inhibition of CXCR4-dependent migration, binding, P-ERK1/2-induction and calcium efflux. Peptides R, S and I were chosen for evaluation in in vivo models of lung metastases (B16-CXCR4 and KTM2 murine osteosarcoma cells and growth of a renal cells xenograft. Peptides R, S, and T significantly reduced the association of the 12G5-CXCR4 antibody to the receptor and inhibited CXCL12-induced calcium efflux. The four peptides efficiently inhibited CXCL12-dependent migration at concentrations as low as 10 nM and delayed CXCL12-mediated wound healing in PES43 human melanoma cells. Intraperitoneal treatment with peptides R, I or S drastically reduced the number of B16-CXCR4-derived lung metastases in C57/BL mice. KTM2 osteosarcoma lung metastases were also reduced in Balb/C mice following CXCR4 inhibition. All three peptides significantly inhibited subcutaneous growth of SN12C-EGFP renal cancer cells. A novel class of CXCR4 inhibitory peptides was discovered. Three peptides, R, I and S inhibited lung metastases and primary tumor growth and will be evaluated as anticancer agents.

  20. Viral Entry through CXCR4 Is a Pathogenic Factor and Therapeutic Target in Human Immunodeficiency Virus Type 1 Disease

    Science.gov (United States)

    Schramm, Birgit; Penn, Michael L.; Speck, Roberto F.; Chan, Stephen Y.; De Clercq, Erik; Schols, Dominique; Connor, Ruth I.; Goldsmith, Mark A.

    2000-01-01

    The chemokine receptors CCR5 and CXCR4 function as the principal coreceptors for human immunodeficiency virus type 1 (HIV-1). Coreceptor function has also been demonstrated for a variety of related receptors in vitro. The relative contributions of CCR5, CXCR4, and other putative coreceptors to HIV-1 disease in vivo have yet to be defined. In this study, we used sequential primary isolates and recombinant strains of HIV-1 to demonstrate that CXCR4-using (X4) viruses emerging in association with disease progression are highly pathogenic in ex vivo lymphoid tissues compared to CXCR4-independent viruses. Furthermore, synthetic receptor antagonists that specifically block CXCR4-mediated entry dramatically suppressed the depletion of CD4+ T cells by recombinant and clinically derived X4 HIV-1 isolates. Moreover, in vitro specificity for the additional coreceptors CCR3, CCR8, BOB, and Bonzo did not augment cytopathicity or diminish sensitivity toward CXCR4 antagonists in lymphoid tissues. These data provide strong evidence to support the concept that adaptation to CXCR4 specificity in vivo accelerates HIV-1 disease progression. Thus, therapeutic intervention targeting the interaction of HIV-1 gp120 with CXCR4 may be highly valuable for suppressing the pathogenic effects of late-stage viruses. PMID:10590105

  1. Evolution and function of chemokine receptors in the immune system of lower vertebrates.

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    Bajoghli, Baubak

    2013-07-01

    Chemokine receptors and their counterpart ligands are one of the evolutionary innovations of vertebrates. They play a guiding role in the coordination of cell trafficking in many biological processes. Comparative syntenic and phylogenetic analyses provide insight into the evolution of chemokine receptors and suggest that the repertoire of chemokine receptors varies in each species, regardless of the evolutionary position of the species. Despite the rapid evolution of chemokine receptors, the expression and function of orthologous chemokine receptors in lower and higher vertebrates are very similar. This is also true for the chemokine ligands that have been examined so far, such as CXCL8, CXCL12, and CCL25. As examples, this review will discuss how the evolution of the chemokine receptor CXCR4 is coincident with the emergence of lymphocytes in jawless vertebrates (lamprey); and that, in jawed vertebrates, CXCR4 and CCR9 are involved in thymus colonization. In myeloid cells, the function of CXCR1 in neutrophils and the expression of CXCR3 in macrophages and DCs are evolutionarily conserved between fish and mammals. In this context, medaka and zebrafish are outstanding models for studying the function of chemokines and their receptors.

  2. Disruption of Stromal-Derived Factor-1/Chemokine Receptor 4 by Simvastatin

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    A Jalili

    2010-03-01

    Full Text Available Background: The alpha chemokine, stromal-derived factor (SDF-1 is produced by bone marrow stromal cells and other cells, especially damaged tissues. SDF-1 receptor, a chemokine receptor 4 (CXCR4, is expressed on inflammatory cells and that SDF-1/CXCR4 axis plays a critical role in migration of inflammatory cells. In cardiovascular diseases, SDF-1 is produced by endothelial cells and plaques and that SDF-1 chemoattracts monocytes to the endothelial cells resulting in a local inflammation. Simvastatin, a cholesterol-lowering agent, is a general drug for treatment of cardiovascular diseases. However, its molecular mechanism has not yet been completely elucidated.Method: Herein, we investigated the role of simvastatin on the SDF- 1/CXCR4 axis by employing flow cytometry, RT-PCR, chemotaxis and adhesion assays. Results: Simvastatin (i downregulates CXCR4 expression on monocytic cell line (THP-1 and primary monocyte in a dose-dependent manner, (ii inhibits adhesion of monocytes to endothelial cells and (iii decreases SDF-1 production by endothelial cells. Moreover, preincubation with simvastatin significantly decreased the migration of THP-1 towards the SDF-1 gradient.Conclusion: All together our data indicate that simvastatin inhibits the binding of monocytes to endothelial cells through disrupting of the SDF-1/CXCR4 axis.

  3. Epigenetic changes of CXCR4 and its ligand CXCL12 as prognostic factors for sporadic breast cancer.

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    Edneia A S Ramos

    Full Text Available Chemokines and their receptors are involved in the development and cancer progression. The chemokine CXCL12 interacts with its receptor, CXCR4, to promote cellular adhesion, survival, proliferation and migration. The CXCR4 gene is upregulated in several types of cancers, including skin, lung, pancreas, brain and breast tumors. In pancreatic cancer and melanoma, CXCR4 expression is regulated by DNA methylation within its promoter region. In this study we examined the role of cytosine methylation in the regulation of CXCR4 expression in breast cancer cell lines and also correlated the methylation pattern with the clinicopathological aspects of sixty-nine primary breast tumors from a cohort of Brazilian women. RT-PCR showed that the PMC-42, MCF7 and MDA-MB-436 breast tumor cell lines expressed high levels of CXCR4. Conversely, the MDA-MB-435 cell line only expressed CXCR4 after treatment with 5-Aza-CdR, which suggests that CXCR4 expression is regulated by DNA methylation. To confirm this hypothesis, a 184 bp fragment of the CXCR4 gene promoter region was cloned after sodium bisulfite DNA treatment. Sequencing data showed that cell lines that expressed CXCR4 had only 15% of methylated CpG dinucleotides, while the cell line that not have CXCR4 expression, had a high density of methylation (91%. Loss of DNA methylation in the CXCR4 promoter was detected in 67% of the breast cancer analyzed. The absence of CXCR4 methylation was associated with the tumor stage, size, histological grade, lymph node status, ESR1 methylation and CXCL12 methylation, metastasis and patient death. Kaplan-Meier curves demonstrated that patients with an unmethylated CXCR4 promoter had a poorer overall survival and disease-free survival. Furthermore, patients with both CXCL12 methylation and unmethylated CXCR4 had a shorter overall survival and disease-free survival. These findings suggest that the DNA methylation status of both CXCR4 and CXCL12 genes could be used as a

  4. Bioinformatics analysis of breast cancer bone metastasis related gene-CXCR4

    Institute of Scientific and Technical Information of China (English)

    Heng-Wei Zhang; Xian-Fu Sun; Ya-Ning He; Jun-Tao Li; Xu-Hui Guo; Hui Liu

    2013-01-01

    Objective: To analyze breast cancer bone metastasis related gene-CXCR4. Methods: This research screened breast cancer bone metastasis related genes by high-flux gene chip. Results:It was found that the expressions of 396 genes were different including 165 up-regulations and 231 down-regulations. The expression of chemokine receptor CXCR4 was obviously up-regulated in the tissue with breast cancer bone metastasis. Compared with the tissue without bone metastasis, there was significant difference, which indicated that CXCR4 played a vital role in breast cancer bone metastasis. Conclusions: The bioinformatics analysis of CXCR4 can provide a certain basis for the occurrence and diagnosis of breast cancer bone metastasis, target gene therapy and evaluation of prognosis.

  5. Downregulation of CXCR4 in Metastasized Breast Cancer Cells and Implication in Their Dormancy.

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    Kentaro Nobutani

    Full Text Available Our understanding of the mechanism of cancer dormancy is emerging, but the underlying mechanisms are not fully understood. Here we analyzed mouse xenograft tumors derived from human breast cancer tissue and the human breast cancer cell line MDA-MB-231 to identify the molecules associated with cancer dormancy. In immunohistological examination using the proliferation marker Ki-67, the tumors included both proliferating and dormant cancer cells, but the number of dormant cells was remarkably increased when they metastasized to the lung. In the gene expression analysis of the orthotopic cancer cells by a single-cell multiplex real-time quantitative reverse transcription PCR followed by flow cytometric analysis, restrained cellular proliferation was associated with downregulation of the chemokine receptor CXCR4. In the immunohistological and flow cytometric analyses, the expression level of CXCR4 in the metastasized cancer cells was decreased compared with that in the cancer cells in orthotopic tumors, although the expression level of the CXCR4 ligand CXCL12 was not reduced in the lung. In addition, the proliferation of the metastasized cancer cells was further decreased by the CXCR4 antagonist administration. In the ex vivo culture of the metastasized cancer cells, the expression level of CXCR4 was increased, and in the xenotransplantation of ex vivo cultured cancer cells, the expression level of CXCR4 was again decreased in the metastasized cancer cells in the lung. These findings indicate that CXCR4 is downregulated in metastasized breast cancer cells and implicated in their dormancy.

  6. The Impact of CXCR4 Blockade on the Survival of Rat Brain Cortical Neurons

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    Merino, José Joaquín; Garcimartín, Alba; López-Oliva, María Elvira; Benedí, Juana; González, María Pilar

    2016-01-01

    Background: Chemokine receptor type 4 (CXCR4) plays a role in neuronal survival/cell repair and also contributes to the progression of cancer and neurodegenerative diseases. Chemokine ligand 12 (CXCL12) binds to CXCR4. In this study, we have investigated whether CXCR4 blockade by AMD3100 (a CXCR4 antagonist, member of bicyclam family) may affect neuronal survival in the absence of insult. Thus, we have measured the mitochondrial membrane potential (MMP), Bax and Bcl-2 protein translocation, and cytochrome c release in AMD3100-treated brain cortical neurons at 7 DIV (days in vitro). Methods: For this aim, AMD3100 (200 nM) was added to cortical neurons for 24 h, and several biomarkers like cell viability, reactive oxygen species (ROS) generation, lactate dehydrogenase (LDH) release, caspase-3/9 activity, proteins Bax and Bcl-2 translocation, and cytochrome c release were analyzed by immunoblot. Results: CXCR4 blockade by AMD3100 (200 nM, 24 h) induces mitochondrial hyperpolarization and increases caspase-3/9 hyperpolarization without affecting LDH release as compared to untreated controls. AMD3100 also increases cytochrome c release and promotes Bax translocation to the mitochondria, whereas it raises cytosolic Bcl-2 levels in brain cortical neurons. Conclusion: CXCR4 blockade induces cellular death via intrinsic apoptosis in rat brain cortical neurons in absence of insult. PMID:27916896

  7. SMM-chemokines: a class of unnatural synthetic molecules as chemical probes of chemokine receptor biology and leads for therapeutic development.

    Science.gov (United States)

    Kumar, Santosh; Choi, Won-Tak; Dong, Chang-Zhi; Madani, Navid; Tian, Shaomin; Liu, Dongxiang; Wang, Youli; Pesavento, James; Wang, Jun; Fan, Xuejun; Yuan, Jian; Fritzsche, Wayne R; An, Jing; Sodroski, Joseph G; Richman, Douglas D; Huang, Ziwei

    2006-01-01

    Chemokines and their receptors play important roles in numerous physiological and pathological processes. To develop natural chemokines into receptor probes and inhibitors of pathological processes, the lack of chemokine-receptor selectivity must be overcome. Here, we apply chemical synthesis and the concept of modular modifications to generate unnatural synthetically and modularly modified (SMM)-chemokines that have high receptor selectivity and affinity, and reduced toxicity. A proof of the concept was shown by transforming the nonselective viral macrophage inflammatory protein-II into new analogs with enhanced selectivity and potency for CXCR4 or CCR5, two principal coreceptors for human immunodeficiency virus (HIV)-1 entry. These new analogs provided insights into receptor binding and signaling mechanisms and acted as potent HIV-1 inhibitors. These results support the concept of SMM-chemokines for studying and controlling the function of other chemokine receptors.

  8. Quantitative phosphoproteomic analysis reveals system-wide signaling pathways downstream of SDF-1/CXCR4 in breast cancer stem cells.

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    Yi, Tingfang; Zhai, Bo; Yu, Yonghao; Kiyotsugu, Yoshikawa; Raschle, Thomas; Etzkorn, Manuel; Seo, Hee-Chan; Nagiec, Michal; Luna, Rafael E; Reinherz, Ellis L; Blenis, John; Gygi, Steven P; Wagner, Gerhard

    2014-05-27

    Breast cancer is the leading cause of cancer-related mortality in women worldwide, with an estimated 1.7 million new cases and 522,000 deaths around the world in 2012 alone. Cancer stem cells (CSCs) are essential for tumor reoccurrence and metastasis which is the major source of cancer lethality. G protein-coupled receptor chemokine (C-X-C motif) receptor 4 (CXCR4) is critical for tumor metastasis. However, stromal cell-derived factor 1 (SDF-1)/CXCR4-mediated signaling pathways in breast CSCs are largely unknown. Using isotope reductive dimethylation and large-scale MS-based quantitative phosphoproteome analysis, we examined protein phosphorylation induced by SDF-1/CXCR4 signaling in breast CSCs. We quantified more than 11,000 phosphorylation sites in 2,500 phosphoproteins. Of these phosphosites, 87% were statistically unchanged in abundance in response to SDF-1/CXCR4 stimulation. In contrast, 545 phosphosites in 266 phosphoproteins were significantly increased, whereas 113 phosphosites in 74 phosphoproteins were significantly decreased. SDF-1/CXCR4 increases phosphorylation in 60 cell migration- and invasion-related proteins, of them 43 (>70%) phosphoproteins are unrecognized. In addition, SDF-1/CXCR4 upregulates the phosphorylation of 44 previously uncharacterized kinases, 8 phosphatases, and 1 endogenous phosphatase inhibitor. Using computational approaches, we performed system-based analyses examining SDF-1/CXCR4-mediated phosphoproteome, including construction of kinase-substrate network and feedback regulation loops downstream of SDF-1/CXCR4 signaling in breast CSCs. We identified a previously unidentified SDF-1/CXCR4-PKA-MAP2K2-ERK signaling pathway and demonstrated the feedback regulation on MEK, ERK1/2, δ-catenin, and PPP1Cα in SDF-1/CXCR4 signaling in breast CSCs. This study gives a system-wide view of phosphorylation events downstream of SDF-1/CXCR4 signaling in breast CSCs, providing a resource for the study of CSC-targeted cancer therapy.

  9. Chemokine receptor specific antibodies in cancer immunotherapy: achievements and challenges

    Directory of Open Access Journals (Sweden)

    Maria eVela

    2015-01-01

    Full Text Available The 1990s brought a burst of information regarding the structure, expression pattern, and role in leukocyte migration and adhesion of chemokines and their receptors. At that time, the FDA approved the first therapeutic antibodies for cancer treatment. A few years later it was reported that the chemokine receptors CXCR4 and CCR7 were involved on directing metastases to liver, lung, bone marrow or lymph nodes, and the over-expression of CCR4, CCR6 and CCR9 by certain tumors. The possibility of inhibiting the interaction of chemokine receptors present on the surface of tumor cells with their ligands emerged as a new therapeutic approach. Therefore, many research groups and companies began to develop small-molecule antagonists and specific antibodies, aiming to neutralize signaling from these receptors. Despite great expectations, so far, only one anti-chemokine receptor antibody has been approved for its clinical use, mogamulizumab, an anti-CCR4 antibody, granted in Japan to treat refractory adult T cell leukemia and lymphoma. Here we review the main achievements obtained with anti-chemokine receptor antibodies for cancer immunotherapy, including discovery and clinical studies, proposed mechanisms of action and therapeutic applications.

  10. Apigenin suppresses migration and invasion of transformed cells through down-regulation of C-X-C chemokine receptor 4 expression

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    Wang, Lei; Kuang, Lisha; Hitron, John Andrew; Son, Young-Ok; Wang, Xin; Budhraja, Amit [Graduate Center for Toxicology, College of Medicine, University of Kentucky, Lexington, KY 40536 (United States); Lee, Jeong-Chae [Graduate Center for Toxicology, College of Medicine, University of Kentucky, Lexington, KY 40536 (United States); Institute of Oral Biosciences and BK21 Program, Research Center of Bioactive Materials, Chonbuk National University, Jeonju 561-756 (Korea, Republic of); Pratheeshkumar, Poyil [Graduate Center for Toxicology, College of Medicine, University of Kentucky, Lexington, KY 40536 (United States); Chen, Gang [Department of Internal Medicine, University of Kentucky College of Medicine, Lexington, KY 40536 (United States); Zhang, Zhuo [Graduate Center for Toxicology, College of Medicine, University of Kentucky, Lexington, KY 40536 (United States); Luo, Jia [Department of Internal Medicine, University of Kentucky College of Medicine, Lexington, KY 40536 (United States); Shi, Xianglin, E-mail: xshi5@email.uky.edu [Graduate Center for Toxicology, College of Medicine, University of Kentucky, Lexington, KY 40536 (United States)

    2013-10-01

    Environmental exposure to arsenic is known to cause various cancers. There are some potential relationships between cell malignant transformation and C-X-C chemokine receptor type 4 (CXCR4) expressions. Metastasis, one of the major characteristics of malignantly transformed cells, contributes to the high mortality of cells. CXCR4 and its natural chemokine ligand C-X-C motif ligand 12 (CXCL12) play a critical role in metastasis. Therefore, identification of nutritional factors which are able to inhibit CXCR4 is important for protection from environmental arsenic-induced carcinogenesis and for abolishing metastasis of malignantly transformed cells. The present study demonstrates that apigenin (4′,5,7-trihydroxyflavone), a natural dietary flavonoid, suppressed CXCR4 expression in arsenic-transformed Beas-2B cells (B-AsT) and several other types of transformed/cancer cells in a dose- and time-dependent manner. Neither proteasome nor lysosome inhibitor had any effect in reducing the apigenin-induced down-regulation of CXCR4, indicating that apigenin-induced down-regulation of CXCR4 is not due to proteolytic degradation. The down-regulation of CXCR4 is mainly due to the inhibition of nuclear factor κB (NF-κB) transcriptional activity. Apigenin also abolished migration and invasion of transformed cells induced by CXCL12. In a xenograft mouse model, apigenin down-regulated CXCR4 expression and suppressed tumor growth. Taken together, our results show that apigenin is a novel inhibitor of CXCR4 expression. This dietary flavonoid has the potential to suppress migration and invasion of transformed cells and prevent environmental arsenic-induced carcinogenesis. - Highlights: • Apigenin has a potential in preventing environmental arsenic induced carcinogenesis. • Apigenin suppresses CXCR4 in malignant transformed cells in vitro and in vivo. • The down-regulation of CXCR4 is mainly due to inhibition of NF-κB activity.

  11. The deubiquitinating enzyme USP8 promotes trafficking and degradation of the chemokine receptor 4 at the sorting endosome.

    Science.gov (United States)

    Berlin, Ilana; Higginbotham, Katherine M; Dise, Rebecca S; Sierra, Maria I; Nash, Piers D

    2010-11-26

    Reversible ubiquitination orchestrated by the opposition of ubiquitin ligases and deubiquitinating enzymes mediates endocytic trafficking of cell surface receptors for lysosomal degradation. Ubiquitin-specific protease 8 (USP8) has previously been implicated in endocytosis of several receptors by virtue of their deubiquitination. The present study explores an indirect role for USP8 in cargo trafficking through its regulation of the chemokine receptor 4 (CXCR4). Contrary to the effects of USP8 loss on enhanced green fluorescent protein, we find that USP8 depletion stabilizes CXCR4 on the cell surface and attenuates receptor degradation without affecting its ubiquitination status. In the presence of ligand, diminished CXCR4 turnover is accompanied by receptor accumulation on enlarged early endosomes and leads to enhancement of phospho-ERK signaling. Perturbation in CXCR4 trafficking, resulting from USP8 inactivation, occurs at the ESCRT-0 checkpoint, and catalytic mutation of USP8 specifically targeted to the ESCRT-0 complex impairs the spatial and temporal organization of the sorting endosome. USP8 functionally opposes the ubiquitin ligase AIP4 with respect to ESCRT-0 ubiquitination, thereby promoting trafficking of CXCR4. Collectively, our findings demonstrate a functional cooperation between USP8, AIP4, and the ESCRT-0 machinery at the early sorting phase of CXCR4 and underscore the versatility of USP8 in shaping trafficking events at the early-to-late endosome transition.

  12. Natural amines inhibit activation of human plasmacytoid dendritic cells through CXCR4 engagement

    Science.gov (United States)

    Smith, Nikaïa; Pietrancosta, Nicolas; Davidson, Sophia; Dutrieux, Jacques; Chauveau, Lise; Cutolo, Pasquale; Dy, Michel; Scott-Algara, Daniel; Manoury, Bénédicte; Zirafi, Onofrio; McCort-Tranchepain, Isabelle; Durroux, Thierry; Bachelerie, Françoise; Schwartz, Olivier; Münch, Jan; Wack, Andreas; Nisole, Sébastien; Herbeuval, Jean-Philippe

    2017-01-01

    Plasmacytoid dendritic cells (pDC) are specialized in secretion of type I interferon in response to pathogens. Here we show that natural monoamines and synthetic amines inhibit pDC activation by RNA viruses. Furthermore, a synthetic analogue of histamine reduces type I interferon production in a mouse model of influenza infection. We identify CXC chemokine receptor 4 (CXCR4) as a receptor used by amines to inhibit pDC. Our study establishes a functional link between natural amines and the innate immune system and identifies CXCR4 as a potential ‘on-off' switch of pDC activity with therapeutic potential. PMID:28181493

  13. SDF-1/CXCR4 axis in Tie2-lineage cells including endothelial progenitor cells contributes to bone fracture healing.

    Science.gov (United States)

    Kawakami, Yohei; Ii, Masaaki; Matsumoto, Tomoyuki; Kuroda, Ryosuke; Kuroda, Tomoya; Kwon, Sang-Mo; Kawamoto, Atsuhiko; Akimaru, Hiroshi; Mifune, Yutaka; Shoji, Taro; Fukui, Tomoaki; Kurosaka, Masahiro; Asahara, Takayuki

    2015-01-01

    CXC chemokine receptor 4 (CXCR4) is a specific receptor for stromal-derived-factor 1 (SDF-1). SDF-1/CXCR4 interaction is reported to play an important role in vascular development. On the other hand, the therapeutic potential of endothelial progenitor cells (EPCs) in fracture healing has been demonstrated with mechanistic insight of vasculogenesis/angiogenesis and osteogenesis enhancement at sites of fracture. The purpose of this study was to investigate the influence of the SDF-1/CXCR4 pathway in Tie2-lineage cells (including EPCs) in bone formation. We created CXCR4 gene conditional knockout mice using the Cre/loxP system and set two groups of mice: Tie2-Cre(ER) CXCR4 knockout mice (CXCR4(-/-) ) and wild-type mice (WT). We report here that in vitro, EPCs derived from of CXCR4(-/-) mouse bone marrow demonstrated severe reduction of migration activity and EPC colony-forming activity when compared with those derived from WT mouse bone marrow. In vivo, radiological and morphological examinations showed fracture healing delayed in the CXCR4(-/-) group and the relative callus area at weeks 2 and 3 was significantly smaller in CXCR4(-/-) group mice. Quantitative analysis of capillary density at perifracture sites also showed a significant decrease in the CXCR4(-/-) group. Especially, CXCR4(-/-) group mice demonstrated significant early reduction of blood flow recovery at fracture sites compared with the WT group in laser Doppler perfusion imaging analysis. Real-time RT-PCR analysis showed that the gene expressions of angiogenic markers (CD31, VE-cadherin, vascular endothelial growth factor [VEGF]) and osteogenic markers (osteocalcin, collagen 1A1, bone morphogenetic protein 2 [BMP2]) were lower in the CXCR4(-/-) group. In the gain-of-function study, the fracture in the SDF-1 intraperitoneally injected WT group healed significantly faster with enough callus formation compared with the SDF-1 injected CXCR4(-/-) group. We demonstrated that an EPC SDF-1/CXCR4 axis plays an

  14. The role of the CXCL12-CXCR4/CXCR7 axis in the progression and metastasis of bone sarcomas (Review).

    Science.gov (United States)

    Liao, Yu-Xin; Zhou, Cheng-Hao; Zeng, Hui; Zuo, Dong-Qing; Wang, Zhuo-Ying; Yin, Fei; Hua, Ying-Qing; Cai, Zheng-Dong

    2013-12-01

    Bone sarcomas, which comprise less than 1% of all human malignancies, are a group of relatively rare mesenchymal-derived tumors. They are mainly composed of osteosarcoma, chondrosarcoma and Ewing's sarcoma. In spite of advances in adjuvant chemotherapy and wide surgical resection, prognosis remains poor due to the high propensity for lung metastasis, which is the leading cause of mortality in patients with bone sarcomas. Chemokines are a superfamily of small pro-inflammatory chemoattractant cytokines which can bind to specific G protein-coupled seven-span transmembrane receptors. Chemokine 12 (CXCL12), also designated as stromal cell-derived factor-1 (SDF-1), is able to bind to its cognate receptors, chemokine receptor 4 (CXCR4) and chemokine receptor 7 (CXCR7), with high affinity. The binding of CXCL12 to CXCR4/CXCR7 stimulates the activation of several downstream signaling pathways that regulate tumor progression and metastasis. In this review, the structure and function of CXCL12 and its receptors, CXCR4 and CXCR7, as well as many factors affecting their expression are discussed. Phosphoinositide 3-kinase (PI3K) and mitogen-activated protein kinase (MAPK) pathways are the two most important downstream pathways regulated by the CXCL12-CXCR4/CXCR7 interaction. CXCR4 expression in bone sarcomas, including tumor cells and samples and the correlation between CXCR4/CXCR7 expression and the survival of patients with bone sarcomas are also discussed. In addition, we review the involvement of the CXCL12‑CXCR4/CXCR7 axis in the growth and metastasis of bone sarcomas and the targeting of this axis in preclinical studies.

  15. X4-tropic human immunodeficiency virus IIIB utilizes CXCR4 as coreceptor, as distinct from R5X4-tropic viruses.

    Science.gov (United States)

    Islam, Salequl; Hoque, Sheikh Ariful; Adnan, Nihad; Tanaka, Atsushi; Jinno-Oue, Atsushi; Hoshino, Hiroo

    2013-06-01

    Human immunodeficiency viruses initiate infections via CCR5 coreceptors and then change their tropism to C-X-C chemokine receptor type 4 (CXCR4), this change being associated with rapid disease progression. HIV-1IIIB, a widely described pure X4-tropic strain, is distinct from R5X4-tropic viruses. In this study, the requirement for amino terminal regions (NTRs) of CXCR4 for entry of HIV-1IIIB virus into host cells was examined and compared to that of R5X4-tropic viruses. CXCR4 and its deletion mutant (CXCR4ΔNTR23; first 23 amino acids removed from NTR) were amplified to examine their coreceptor activities. NP-2/CD4/CXCR4 and NP-2/CD4/CXCR4ΔNTR23 cell lines were prepared accordingly. Indirect immune fluorescence assay (IFA), PCR, and reverse transcriptase (RT) activity were used to compare the process of infection of host cells by HIV-1IIIB virus, one R5-tropic and five other R5X4-tropic viruses. All the R5X4-tropic HIVs were found to utilize both CCR5 and CXCR4 but unable to use CXCR4ΔNTR23 as coreceptors. In contrast, X4-tropic HIV-1IIIB was found to preferentially infect through CXCR4ΔNTR23. Viral antigens in infected NP-2/CD4/CXCR4ΔNTR23 cells were detected by IFA and confirmed by detection of proviral DNA and by performing RT assays on the spent cell-supernatants. In dual tropic viruses, deletion of 23 amino acids from NTR abrogates the coreceptor activity of CXCR4. This observation demonstrates that NTR of CXCR4 have an obligatory coreceptor role for dual tropic viruses. However, HIV-1IIIB may have different requirements for NTR than R5X4 viruses or may infect host cells independent of NTR of CXCR4.

  16. Crosstalk between SDF-1/CXCR4 and SDF-1/CXCR7 in cardiac stem cell migration.

    Science.gov (United States)

    Chen, Dong; Xia, Yanli; Zuo, Ke; Wang, Ying; Zhang, Shiying; Kuang, Dong; Duan, Yaqi; Zhao, Xia; Wang, Guoping

    2015-11-18

    Stromal cell-derived factor 1 (SDF-1) is a chemokine that can be expressed in injured cardiomyocytes after myocardial infarction (MI). By combining with its receptor CXCR4, SDF-1 induced stem and progenitor cells migration. CXCR7, a novel receptor for SDF-1, has been identified recently. We aimed to explore the roles of SDF-1/CXCR4 and SDF-1/CXCR7 pathway and their crosstalk in CSCs migration. In the present study, CXCR4 and CXCR7 expression were identified in CSCs. Transwell assay showed that SDF-1 caused CSCs migration in a dose- and time-dependent manner, which could be significantly suppressed by CXCR4 or CXCR7 siRNA. Phospho-ERK, phospho-Akt and Raf-1 significantly elevated in CSCs with SDF-1 stimulation. Knockdown of CXCR4 or CXCR7 significantly decreased phospho-ERK or phospho-Akt, respectively, and eventually resulted in the inhibition of CSCs migration. Moreover, western blot showed that MK2206 (Akt inhibitor) increased the expression of phospho-ERK and Raf-1, whereas PD98059 (ERK inhibitor) had no effect on phospho-Akt and Raf-1. GW5074 (Raf-1 inhibitor) upregulated the expression of phospho-ERK, but had no effect on phospho-Akt. The present study indicated that SDF-1/CXCR7/Akt and SDF-1/CXCR4/ERK pathway played important roles in CSCs migration. Akt phosphorylation inhibited Raf-1 activity, which in turn dephosphorylated ERK and negatively regulated CSCs migration.

  17. CXCR4 activation promotes differentiation of human embryonic stem cells to neural stem cells.

    Science.gov (United States)

    Zhang, Lijun; Hua, Qiuhong; Tang, Kaiyi; Shi, Changjie; Xie, Xin; Zhang, Ru

    2016-11-19

    G protein-coupled receptors (GPCRs) are involved in many fundamental cellular responses such as growth, death, movement, transcription and excitation. Their roles in human stem cell neural specialization are not well understood. In this study, we aimed to identify GPCRs that may play a role in the differentiation of human embryonic stem cells (hESCs) to neural stem cells (NSCs). Using a feeder-free hESC neural differentiation protocol, we found that the expression of several chemokine receptors changed dramatically during the hESC/NSC transition. Especially, the expression of CXCR4 increased approximately 50 folds in NSCs compared to the original hESCs. CXCR4 agonist SDF-1 promoted, whereas the antagonist AMD3100 delayed the neural induction process. In consistence with antagonizing CXCR4, knockdown of CXCR4 in hESCs also blocked the neural induction and cells with reduced CXCR4 were rarely positive for Nestin and Sox1-staining. Taken together, our results suggest that CXCR4 is involved in the neural induction process of hESC and it might be considered as a target to facilitate NSC production from hESCs in regenerative medicine.

  18. The Significance of CXCR4 Expression for the Prediction of Lymph Node Metastasis in Breast Cancer Patients

    Institute of Scientific and Technical Information of China (English)

    Yongxing Ding; Chenghua Li; Qingling Yang; Changjie Chen; Zenong Cheng

    2008-01-01

    OBJECTIVE The chemokine receptor (CXCR4) CXC chemokine receptor 4) plays an important role in cancer metastasis. We therefore studied differential expression of the CXCR4, as well as that of the biomarker HER2, so as to evaluate whether these biomarkers can be used to predict axillary lymph node metastasis in breast cancer patients.METHODS Immunohistochemistry was used to evaluate the CXCR4 and HER2 expressions and to examine the paraffin sections of the breast cancers at various stages. Positive lymph node expression was found in 80 of the cases, and in 7 there was negative expression.RESULTS Compared to the cases with negative lymph nodes,there was a high expression of CXCR4 (26.3% vs. 14.3%, P = 0.013),and an over-expression of HER2 (28.8% vs. 14.3%, P = 0.011).Moreover, there was a direct correlation between the CXCR4 and HER2 expressions and the tumor staging (P = 0.000) and lymph node metastasis (P = 0.032). When the two biomarkers, I.e. CXCR4 and HER2, were concurrently labeled, a high expression of one of the biomarkers could be seen in the cases with positive lymph nodes (51.3% vs. 28.6%, P < 0.003).CONCLUSION The chemokine receptor, CXCR4, is a new-type biomarker in predicting axillary lymph-node metastasis in breast cancers. Compared with the other markers, such as HER2 etc.,assessment of CXCR4 can improve the prediction of the presence and extent of lymph node involvement.

  19. HIV-1 with multiple CCR5/CXCR4 chimeric receptor use is predictive of immunological failure in infected children.

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    Mariangela Cavarelli

    Full Text Available BACKGROUND: HIV-1 R5 viruses are characterized by a large phenotypic variation, that is reflected by the mode of coreceptor use. The ability of R5 HIV-1 to infect target cells expressing chimeric receptors between CCR5 and CXCR4 (R5(broad viruses, was shown to correlate with disease stage in HIV-1 infected adults. Here, we ask the question whether phenotypic variation of R5 viruses could play a role also in mother-to-child transmission (MTCT of HIV-1 and pediatric disease progression. METHODOLOGY/PRINCIPAL FINDINGS: Viral isolates obtained from a total of 59 HIV-1 seropositive women (24 transmitting and 35 non transmitting and 28 infected newborn children, were used to infect U87.CD4 cells expressing wild type or six different CCR5/CXCR4 chimeric receptors. HIV-1 isolates obtained from newborn infants had predominantly R5(narrow phenotype (n = 20, but R5(broad and R5X4 viruses were also found in seven and one case, respectively. The presence of R5(broad and R5X4 phenotypes correlated significantly with a severe decline of the CD4+ T cells (CDC stage 3 or death within 2 years of age. Forty-three percent of the maternal R5 isolates displayed an R5(broad phenotype, however, the presence of the R5(broad virus was not predictive for MTCT of HIV-1. Of interest, while only 1 of 5 mothers with an R5X4 virus transmitted the dualtropic virus, 5 of 6 mothers carrying R5(broad viruses transmitted viruses with a similar broad chimeric coreceptor usage. Thus, the maternal R5(broad phenotype was largely preserved during transmission and could be predictive of the phenotype of the newborn's viral variant. CONCLUSIONS/SIGNIFICANCE: Our results show that R5(broad viruses are not hampered in transmission. When transmitted, immunological failure occurs earlier than in children infected with HIV-1 of R5(narrow phenotype. We believe that this finding is of utmost relevance for therapeutic interventions in pediatric HIV-1 infection.

  20. Analysis of Chemokines and Receptors Expression Profile in the Myelin Mutant Taiep Rat

    Science.gov (United States)

    Soto-Rodriguez, Guadalupe; Gonzalez-Barrios, Juan-Antonio; Martinez-Fong, Daniel; Blanco-Alvarez, Victor-Manuel; Eguibar, Jose R.; Ugarte, Araceli; Martinez-Perez, Francisco; Millán-Perez Peña, Lourdes; Pazos-Salazar, Nidia-Gary; Torres-Soto, Maricela; Garcia-Robles, Guadalupe; Tomas-Sanchez, Constantino

    2015-01-01

    Taiep rat has a failure in myelination and remyelination processes leading to a state of hypomyelination throughout its life. Chemokines, which are known to play a role in inflammation, are also involved in the remyelination process. We aimed to demonstrate that remyelination-stimulating factors are altered in the brainstem of 1- and 6-month-old taiep rats. We used a Rat RT2 Profiler PCR Array to assess mRNA expression of 84 genes coding for cytokines, chemokines, and their receptors. We also evaluated protein levels of CCL2, CCR1, CCR2, CCL5, CCR5, CCR8, CXCL1, CXCR2, CXCR4, FGF2, and VEGFA by ELISA. Sprague-Dawley rats were used as a control. PCR Array procedure showed that proinflammatory cytokines were not upregulated in the taiep rat. In contrast, some mRNA levels of beta and alpha chemokines were upregulated in 1-month-old rats, but CXCR4 was downregulated at their 6 months of age. ELISA results showed that CXCL1, CCL2, CCR2, CCR5, CCR8, and CXCR4 protein levels were decreased in brainstem at the age of 6 months. These results suggest the presence of a chronic neuroinflammation process with deficiency of remyelination-stimulating factors (CXCL1, CXCR2, and CXCR4), which might account for the demyelination in the taiep rat. PMID:25883747

  1. Analysis of Chemokines and Receptors Expression Profile in the Myelin Mutant Taiep Rat

    Directory of Open Access Journals (Sweden)

    Guadalupe Soto-Rodriguez

    2015-01-01

    Full Text Available Taiep rat has a failure in myelination and remyelination processes leading to a state of hypomyelination throughout its life. Chemokines, which are known to play a role in inflammation, are also involved in the remyelination process. We aimed to demonstrate that remyelination-stimulating factors are altered in the brainstem of 1- and 6-month-old taiep rats. We used a Rat RT2 Profiler PCR Array to assess mRNA expression of 84 genes coding for cytokines, chemokines, and their receptors. We also evaluated protein levels of CCL2, CCR1, CCR2, CCL5, CCR5, CCR8, CXCL1, CXCR2, CXCR4, FGF2, and VEGFA by ELISA. Sprague-Dawley rats were used as a control. PCR Array procedure showed that proinflammatory cytokines were not upregulated in the taiep rat. In contrast, some mRNA levels of beta and alpha chemokines were upregulated in 1-month-old rats, but CXCR4 was downregulated at their 6 months of age. ELISA results showed that CXCL1, CCL2, CCR2, CCR5, CCR8, and CXCR4 protein levels were decreased in brainstem at the age of 6 months. These results suggest the presence of a chronic neuroinflammation process with deficiency of remyelination-stimulating factors (CXCL1, CXCR2, and CXCR4, which might account for the demyelination in the taiep rat.

  2. Role of CXCR4 expression in progress and prognosis of breast cancer%CXCR4表达对乳腺癌进展及预后的意义

    Institute of Scientific and Technical Information of China (English)

    陈宏武; 吴国英; 张国君

    2011-01-01

    CXCR4 是编码352个氨基酸且高度保守的G蛋白耦联七次跨膜受体,可介导肿瘤细胞增殖、迁移、浸润及转移,在乳腺癌发生发展及转移过程中起着关键作用.CXCR4表达是乳腺癌发生的早期分子事件,可能为预测乳腺癌发生及早期诊断乳腺癌提供新的方法.CXCR4高表达与乳腺癌转移有着密切关系,是乳腺癌预后不良的重要指标.抑制CXCR4表达或阻断CXCR4信号通路,可抑制肿瘤细胞生长、增殖及转移,CXCR4 拮抗剂可能成为乳腺癌新的靶向治疗药物.%CXCR4, a receptor for stromal cell-derived factor-1 (SDF-1, also know as CXCL12) and a member of the chemokine receptor family, has been shown to play an important role in the proliferation, migration, invasion and metastasis of breast cancer cells. CXCR4 expression is an early event in breast cancer development and may serve as a biomarker for early detection and diagnosis of breast cancer. Expression of CXCR4 has been demonstrated to correlate with metastasis and poor prognosis in breast cancer. Inhibition of CXCR4 expression may be a potential target of breast cancer treatment.

  3. CXCL12/CXCR4-Axis Dysfunctions: Markers of the Rare Immunodeficiency Disorder WHIM Syndrome

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    Françoise Bachelerie

    2010-01-01

    Full Text Available The WHIM syndrome features susceptibility to human Papillomavirus infection-induced warts and carcinomas, hypogammaglobulinemia, recurrent bacterial infections, B and T-cell lymphopenia, and neutropenia associated with retention of senescent neutrophils in the bone marrow (i.e. myelokathexis. This rare disorder is mostly linked to inherited heterozygous autosomal dominant mutations in the gene encoding CXCR4, a G protein coupled receptor with a unique ligand, the chemokine CXCL12/SDF-1. Some individuals who have full clinical forms of the syndrome carry a wild type CXCR4 gene. In spite of this genetic heterogeneity, leukocytes from WHIM patients share in common dysfunctions of the CXCR4-mediated signaling pathway upon exposure to CXCL12. Dysfunctions are characterized by impaired desensitization and receptor internalization, which are associated with enhanced responses to the chemokine. Our increasing understanding of the mechanisms that account for the aberrant CXCL12/CXCR4-mediated responses is beginning to provide insight into the pathogenesis of the disorder. As a result we can expect to identify markers of the WHIM syndrome, as well as other disorders with WHIM-like features that are associated with dysfunctions of the CXCL12/CXCR4 axis.

  4. Heterophilic chemokine receptor interactions in chemokine signaling and biology.

    Science.gov (United States)

    Kramp, Birgit K; Sarabi, Alisina; Koenen, Rory R; Weber, Christian

    2011-03-10

    It is generally accepted that G-protein coupled receptors (GPCR), like chemokine receptors, form dimers or higher order oligomers. Such homo- and heterophilic interactions have been identified not only among and between chemokine receptors of CC- or CXC-subfamilies, but also between chemokine receptors and other classes of GPCR, like the opioid receptors. Oligomerization affects different aspects of receptor physiology, like ligand affinity, signal transduction and the mode of internalization, in turn influencing physiologic processes such as cell activation and migration. As particular chemokine receptor pairs exert specific modulating effects on their individual functions, they might play particular roles in various disease types, such as cancer. Hence, chemokine receptor heteromers might represent attractive therapeutic targets. This review highlights the state-of-the-art knowledge on the technical and functional aspects of chemokine receptor multimerization in chemokine signaling and biology.

  5. PGK1 as Predictor of CXCR4 Expression, Bone Marrow Metastases and Survival in Neuroblastoma

    Science.gov (United States)

    von Loga, Katharina; Escherich, Gabriele; Wenke, Katharina; Izbicki, Jakob R.; Reinshagen, Konrad; Gros, Stephanie J.

    2013-01-01

    Background and Aim A close relationship between phosphoglycerate kinase 1 (PGK1) and the CXCR4/SDF1 axis (chemokine receptor 4/stromal cell derived factor 1) has been shown for several cancers. However, the role of PGK1 has not been investigated for neuroblastoma, and PGK1 might be a therapeutic target for this tumor entity. The aim of the current study was to evaluate the role of PGK1 expression in neuroblastoma patients, to determine the impact of PGK1 expression levels on survival, and to correlate PGK1 expression with CXCR4 expression and bone marrow dissemination. Materials and Methods Samples from 22 patients with neuroblastoma that were surgically treated at the University Medical Center Hamburg-Eppendorf were evaluated for expression of PGK1 and CXCR4 using immunohistochemistry. Results were correlated with clinical parameters, metastases and outcome of patients. Immunocytochemistry, proliferation and expression analysis of CXCR4 and PGK1 were performed in neuroblastoma cell lines. Results PGK1 is expressed in neuroblastoma cells. PGK1 expression is significantly positively correlated with CXCR4 expression and tumor dissemination to the bone marrow. Moreover the expression of PGK1 is significantly associated with a negative impact on survival in patients with neuroblastoma. PGK1 is downregulated by inhibition of CXCR4 in neuroblastoma cells. Conclusion PGK1 appears to play an important role for neuroblastoma, predicting survival and tumor dissemination. Further in vivo studies outstanding, it is a candidate target for novel therapeutic strategies. PMID:24376734

  6. PGK1 as predictor of CXCR4 expression, bone marrow metastases and survival in neuroblastoma.

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    Helen M Ameis

    Full Text Available BACKGROUND AND AIM: A close relationship between phosphoglycerate kinase 1 (PGK1 and the CXCR4/SDF1 axis (chemokine receptor 4/stromal cell derived factor 1 has been shown for several cancers. However, the role of PGK1 has not been investigated for neuroblastoma, and PGK1 might be a therapeutic target for this tumor entity. The aim of the current study was to evaluate the role of PGK1 expression in neuroblastoma patients, to determine the impact of PGK1 expression levels on survival, and to correlate PGK1 expression with CXCR4 expression and bone marrow dissemination. MATERIALS AND METHODS: Samples from 22 patients with neuroblastoma that were surgically treated at the University Medical Center Hamburg-Eppendorf were evaluated for expression of PGK1 and CXCR4 using immunohistochemistry. Results were correlated with clinical parameters, metastases and outcome of patients. Immunocytochemistry, proliferation and expression analysis of CXCR4 and PGK1 were performed in neuroblastoma cell lines. RESULTS: PGK1 is expressed in neuroblastoma cells. PGK1 expression is significantly positively correlated with CXCR4 expression and tumor dissemination to the bone marrow. Moreover the expression of PGK1 is significantly associated with a negative impact on survival in patients with neuroblastoma. PGK1 is downregulated by inhibition of CXCR4 in neuroblastoma cells. CONCLUSION: PGK1 appears to play an important role for neuroblastoma, predicting survival and tumor dissemination. Further in vivo studies outstanding, it is a candidate target for novel therapeutic strategies.

  7. Human cytomegalovirus-encoded UL33 and UL78 heteromerize with host CCR5 and CXCR4 impairing their HIV coreceptor activity.

    Science.gov (United States)

    Tadagaki, Kenjiro; Tudor, Daniela; Gbahou, Florence; Tschische, Pia; Waldhoer, Maria; Bomsel, Morgane; Jockers, Ralf; Kamal, Maud

    2012-05-24

    Human cytomegalovirus (HCMV) encodes four 7-transmembrane-spanning (7TM) proteins, US28, US27, UL33, and UL78, which present important sequence homology with human chemokine receptors. Whereas US28 binds a large range of chemokines and disturbs host cell signaling at different levels, the others are orphans with largely unknown functions. Assembly of 2 different 7TM proteins into hetero-oligomeric complexes may profoundly change their respective functional properties. We show that HCMV-encoded UL33 and UL78 form heteromers with CCR5 and CXCR4 chemokine receptors in transfected human embryonic kidney 293T cells and monocytic THP-1 cells. Expression of UL33 and UL78 had pleiotropic, predominantly negative, effects on CCR5 and CXCR4 cell surface expression, ligand-induced internalization, signal transduction, and migration without modifying the chemokine binding properties of CCR5 and CXCR4. Importantly, the coreceptor activity of CCR5 and CXCR4 for HIV was largely impaired in the presence of UL33 and UL78 without affecting expression of the primary HIV entry receptor CD4 and its interaction with CCR5 and CXCR4. Collectively, we identified the first molecular function for the HCMV-encoded orphan UL33 and UL78 7TM proteins, namely the regulation of cellular chemokine receptors through receptor heteromerization.

  8. Adenosine stimulates the migration of human endothelial progenitor cells. Role of CXCR4 and microRNA-150.

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    Magali Rolland-Turner

    Full Text Available BACKGROUND: Administration of endothelial progenitor cells (EPC represents a promising option to regenerate the heart after myocardial infarction, but is limited because of low recruitment and engraftment in the myocardium. Mobilization and migration of EPC are mainly controlled by stromal cell-derived factor 1α (SDF-1α and its receptor CXCR4. We hypothesized that adenosine, a cardioprotective molecule, may improve the recruitment of EPC to the heart. METHODS: EPC were obtained from peripheral blood mononuclear cells of healthy volunteers. Expression of chemokines and their receptors was evaluated using microarrays, quantitative PCR, and flow cytometry. A Boyden chamber assay was used to assess chemotaxis. Recruitment of EPC to the infarcted heart was evaluated in rats after permanent occlusion of the left anterior descending coronary artery. RESULTS: Microarray analysis revealed that adenosine modulates the expression of several members of the chemokine family in EPC. Among these, CXCR4 was up-regulated by adenosine, and this result was confirmed by quantitative PCR (3-fold increase, P<0.001. CXCR4 expression at the cell surface was also increased. This effect involved the A(2B receptor. Pretreatment of EPC with adenosine amplified their migration towards recombinant SDF-1α or conditioned medium from cardiac fibroblasts. Both effects were abolished by CXCR4 blocking antibodies. Adenosine also increased CXCR4 under ischemic conditions, and decreased miR-150 expression. Binding of miR-150 to the 3' untranslated region of CXCR4 was verified by luciferase assay. Addition of pre-miR-150 blunted the effect of adenosine on CXCR4. Administration of adenosine to rats after induction of myocardial infarction stimulated EPC recruitment to the heart and enhanced angiogenesis. CONCLUSION: Adenosine increases the migration of EPC. The mechanism involves A(2B receptor activation, decreased expression of miR-150 and increased expression of CXCR4. These

  9. SDF-1 signaling via the CXCR4-TCR heterodimer requires PLC-β3 and PLC-γ1 for distinct cellular responses 1

    Science.gov (United States)

    Kremer, Kimberly N.; Clift, Ian C.; Miamen, Alexander G.; Bamidele, Adebowale O.; Qian, Nan-Xin; Humphreys, Troy D.; Hedin, Karen E.

    2011-01-01

    The CXCR4 chemokine receptor is a G protein-coupled receptor (GPCR) that signals in T lymphocytes by forming a heterodimer with the T cell antigen receptor (TCR). CXCR4 and TCR functions are consequently highly cross-regulated, affecting T cell immune activation, cytokine secretion, and T cell migration. The CXCR4-TCR heterodimer stimulates T cell migration and activation of the ERK MAP kinase and downstream AP-1-dependent cytokine transcription in response to SDF-1, the sole chemokine ligand of CXCR4. These responses require Gi-type G proteins as well as TCR ITAM domains and the ZAP-70 tyrosine kinase, thus indicating that the CXCR4-TCR heterodimer signals to integrate GPCR-associated and TCR-associated signaling molecules in response to SDF-1. Yet, the phospholipase C (PLC) isozymes responsible for coupling the CXCR4-TCR heterodimer to distinct downstream cellular responses are incompletely characterized. Here, we demonstrate that PLC activity is required for SDF-1 to induce ERK activation, migration, and CXCR4 endocytosis in human T cells. SDF-1 signaling via the CXCR4-TCR heterodimer uses PLC-β3 to activate the Ras-ERK pathway and increase intracellular Ca2+ concentrations, while PLC-γ1 is dispensable for these outcomes. In contrast, PLC-γ1, but not PLC-β3, is required for SDF-1-mediated migration, via a mechanism independent of LAT. These results increase understanding of the signaling mechanisms employed by the CXCR4-TCR heterodimer, characterize new roles for PLC-β3 and PLC-γ1 in T cells, and suggest that multiple PLCs may also be activated downstream of other chemokine receptors in order to distinctly regulate migration versus other signaling functions. PMID:21705626

  10. Teleost Chemokines and Their Receptors

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    Steve Bird

    2015-11-01

    Full Text Available Chemokines are a superfamily of cytokines that appeared about 650 million years ago, at the emergence of vertebrates, and are responsible for regulating cell migration under both inflammatory and physiological conditions. The first teleost chemokine gene was reported in rainbow trout in 1998. Since then, numerous chemokine genes have been identified in diverse fish species evidencing the great differences that exist among fish and mammalian chemokines, and within the different fish species, as a consequence of extensive intrachromosomal gene duplications and different infectious experiences. Subsequently, it has only been possible to establish clear homologies with mammalian chemokines in the case of some chemokines with well-conserved homeostatic roles, whereas the functionality of other chemokine genes will have to be independently addressed in each species. Despite this, functional studies have only been undertaken for a few of these chemokine genes. In this review, we describe the current state of knowledge of chemokine biology in teleost fish. We have mainly focused on those species for which more research efforts have been made in this subject, specially zebrafish (Danio rerio, rainbow trout (Oncorhynchus mykiss and catfish (Ictalurus punctatus, outlining which genes have been identified thus far, highlighting the most important aspects of their expression regulation and addressing any known aspects of their biological role in immunity. Finally, we summarise what is known about the chemokine receptors in teleosts and provide some analysis using recently available data to help characterise them more clearly.

  11. Structure-Activity Relationship and Signaling of New Chimeric CXCR4 Agonists.

    Science.gov (United States)

    Mona, Christine E; Besserer-Offroy, Élie; Cabana, Jérôme; Lefrançois, Marilou; Boulais, Philip E; Lefebvre, Marie-Reine; Leduc, Richard; Lavigne, Pierre; Heveker, Nikolaus; Marsault, Éric; Escher, Emanuel

    2016-08-25

    The CXCR4 receptor binds with meaningful affinities only CXCL12 and synthetic antagonists/inverse agonists. We recently described high affinity synthetic agonists for this chemokine receptor, obtained by grafting the CXCL12 N-terminus onto the inverse agonist T140. While those chimeric molecules behave as agonists for CXCR4, their binding and activation mode are unknown. The present SAR of those CXCL12-oligopeptide grafts reveals the key determinants involved in CXCR4 activation. Position 3 (Val) controls affinity, whereas position 7 (Tyr) acts as an efficacy switch. Chimeric molecules bearing aromatic residues in position 3 possess high binding affinities for CXCR4 and are Gαi full agonists with robust chemotactic properties. Fine-tuning of electron-poor aromatic rings in position 7 enhances receptor activation. To rationalize these results, a homology model of a receptor-ligand complex was built using the published crystal structures of CXCR4. Molecular dynamics simulations reveal further details accounting for the observed SAR for this series.

  12. Imaging of Chemokine Receptor 4 Expression in Neuroendocrine Tumors - a Triple Tracer Comparative Approach.

    Science.gov (United States)

    Werner, Rudolf A; Weich, Alexander; Higuchi, Takahiro; Schmid, Jan S; Schirbel, Andreas; Lassmann, Michael; Wild, Vanessa; Rudelius, Martina; Kudlich, Theodor; Herrmann, Ken; Scheurlen, Michael; Buck, Andreas K; Kropf, Saskia; Wester, Hans-Jürgen; Lapa, Constantin

    2017-01-01

    C-X-C motif chemokine receptor 4 (CXCR4) and somatostatin receptors (SSTR) are overexpressed in gastro-entero-pancreatic neuroendocrine tumors (GEP-NET). In this study, we aimed to elucidate the feasibility of non-invasive CXCR4 positron emission tomography/computed tomography (PET/CT) imaging in GEP-NET patients using [(68)Ga]Pentixafor in comparison to (68)Ga-DOTA-D-Phe-Tyr3-octreotide ([(68)Ga]DOTATOC) and (18)F-fluorodeoxyglucose ([(18)F]FDG). Twelve patients with histologically proven GEP-NET (3xG1, 4xG2, 5xG3) underwent [(68)Ga]DOTATOC, [(18)F]FDG, and [(68)Ga]Pentixafor PET/CT for staging and planning of the therapeutic management. Scans were analyzed on a patient as well as on a lesion basis and compared to immunohistochemical staining patterns of CXCR4 and somatostatin receptors SSTR2a and SSTR5. [(68)Ga]Pentixafor visualized tumor lesions in 6/12 subjects, whereas [(18)F]FDG revealed sites of disease in 10/12 and [(68)Ga]DOTATOC in 11/12 patients, respectively. Regarding sensitivity, SSTR-directed PET was the superior imaging modality in all G1 and G2 NET. CXCR4-directed PET was negative in all G1 NET. In contrast, 50% of G2 and 80% of G3 patients exhibited [(68)Ga]Pentixafor-positive tumor lesions. Whereas CXCR4 seems to play only a limited role in detecting well-differentiated NET, increasing receptor expression could be non-invasively observed with increasing tumor grade. Thus, [(68)Ga]Pentixafor PET/CT might serve as non-invasive read-out for evaluating the possibility of CXCR4-directed endoradiotherapy in advanced dedifferentiated SSTR-negative tumors.

  13. Down-regulation of CXCR4 expression by tamoxifen is associated with DNA methyltransferase 3B up-regulation in MCF-7 breast cancer cells.

    Science.gov (United States)

    Kubarek, Ł; Kozłowska, A; Przybylski, M; Lianeri, M; Jagodzinski, P P

    2009-09-01

    The CXCR4 chemokine receptor is a seven transmembrane G protein-coupled receptor present on the surface of various cells including cancer cells. The CXCR4 receptor contributes to the induction of several intracellular signalling pathways that enhance survival, proliferation, and migration of malignant cells. We observed that tamoxifen (Tam) reduced the CXCR4 transcript and protein levels in MCF-7 breast cancer cells. However, we did not see a Tam effect on CXCR4 transcript and protein levels in MCF-7(LVMT3B) cells with RNA interference-mediated knockdown of DNMT3B. We also observed that Tam significantly increased, for several hours, the expression of enzymatically active DNMT3B splice variants in MCF-7 cells. However, there was no Tam effect on these DNMT3B splice variants' expression in MCF-7(LVMT3B) cells. Bisulfite sequencing suggests that Tam may reduce CXCR4 expression via increased methylation of cytosine in the cytosine-guanosine (CpG) dinucleotide island of the CXCR4 promoter of MCF-7 breast cancer cells. Our findings suggest that Tam induces an increase in DNMT3B expression that is associated with the increase of CpG dinucleotide methylation in the CXCR4 promoter and significant reduction of CXCR4 gene expression in MCF-7 cells.

  14. Cxcr4 is transiently expressed in both epithelial and mesenchymal compartments of nascent hair follicles but is not required for follicle formation.

    Science.gov (United States)

    Sennett, Rachel; Rezza, Amélie; Dauber, Katherine L; Clavel, Carlos; Rendl, Michael

    2014-10-01

    Hair follicle (HF) morphogenesis relies on the coordinated exchange of signals between mesenchymal and epithelial compartments of embryonic skin. Chemokine receptor Cxcr4 expression was recently identified in dermal condensates (DCs) of nascent HFs, but its role in promoting HF morphogenesis remains unknown. Our analyses confirmed Cxcr4 expression in condensate cells, and additionally revealed transient Cxcr4 expression in incipient epithelial hair placodes. Placodal Cxcr4 appeared prior to detection in DCs, representing a switch of expression between epithelial and mesenchymal compartments. To explore the functional role of this receptor in both compartments for early HF formation, we conditionally ablated Cxcr4 with condensate-targeting Tbx18(cre) knock-in and epidermis-targeting Krt14-cre transgenic mice. Conditional knockouts for both crosses were viable throughout embryogenesis and into adulthood. Morphological and biochemical marker analyses revealed comparable numbers of HFs forming in knockout embryos compared to wild-type littermate controls in both cases, suggesting that neither dermal nor epithelial Cxcr4 expression is required for early HF morphogenesis. We conclude that Cxcr4 expression and chemokine signaling through this receptor in embryonic mouse skin is dispensable for HF formation.

  15. Chemokines and Chemokine Receptors in the Development of Lupus Nephritis

    OpenAIRE

    Xiaofeng Liao; Tharshikha Pirapakaran; Luo, Xin M

    2016-01-01

    Lupus nephritis (LN) is a major cause of morbidity and mortality in the patients with systemic lupus erythematosus (SLE), an autoimmune disease with damage to multiple organs. Leukocyte recruitment into the inflamed kidney is a critical step to promote LN progression, and the chemokine/chemokine receptor system is necessary for leukocyte recruitment. In this review, we summarize recent studies on the roles of chemokines and chemokine receptors in the development of LN and discuss the potentia...

  16. Dopamine receptor-interacting protein 78 acts as a molecular chaperone for CCR5 chemokine receptor signaling complex organization.

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    Yi-Qun Kuang

    Full Text Available Chemokine receptors are members of the G protein-coupled receptor (GPCR family. CCR5 and CXCR4 act as co-receptors for human immunodeficiency virus (HIV and several efforts have been made to develop ligands to inhibit HIV infection by blocking those receptors. Removal of chemokine receptors from the cell surface using polymorphisms or other means confers some levels of immunity against HIV infection. Up to now, very limited success has been obtained using ligand therapies so we explored potential avenues to regulate chemokine receptor expression at the plasma membrane. We identified a molecular chaperone, DRiP78, that interacts with both CXCR4 and CCR5, but not the heterodimer formed by these receptors. We further characterized the effects of DRiP78 on CCR5 function. We show that the molecular chaperone inhibits CCR5 localization to the plasma membrane. We identified the interaction region on the receptor, the F(x6LL motif, and show that upon mutation of this motif the chaperone cannot interact with the receptor. We also show that DRiP78 is involved in the assembly of CCR5 chemokine signaling complex as a homodimer, as well as with the Gαi protein. Finally, modulation of DRiP78 levels will affect receptor functions, such as cell migration in cells that endogenously express CCR5. Our results demonstrate that modulation of the functions of a chaperone can affect signal transduction at the cell surface.

  17. Dopamine receptor-interacting protein 78 acts as a molecular chaperone for CCR5 chemokine receptor signaling complex organization.

    Science.gov (United States)

    Kuang, Yi-Qun; Charette, Nicholle; Frazer, Jennifer; Holland, Patrick J; Attwood, Kathleen M; Dellaire, Graham; Dupré, Denis J

    2012-01-01

    Chemokine receptors are members of the G protein-coupled receptor (GPCR) family. CCR5 and CXCR4 act as co-receptors for human immunodeficiency virus (HIV) and several efforts have been made to develop ligands to inhibit HIV infection by blocking those receptors. Removal of chemokine receptors from the cell surface using polymorphisms or other means confers some levels of immunity against HIV infection. Up to now, very limited success has been obtained using ligand therapies so we explored potential avenues to regulate chemokine receptor expression at the plasma membrane. We identified a molecular chaperone, DRiP78, that interacts with both CXCR4 and CCR5, but not the heterodimer formed by these receptors. We further characterized the effects of DRiP78 on CCR5 function. We show that the molecular chaperone inhibits CCR5 localization to the plasma membrane. We identified the interaction region on the receptor, the F(x)6LL motif, and show that upon mutation of this motif the chaperone cannot interact with the receptor. We also show that DRiP78 is involved in the assembly of CCR5 chemokine signaling complex as a homodimer, as well as with the Gαi protein. Finally, modulation of DRiP78 levels will affect receptor functions, such as cell migration in cells that endogenously express CCR5. Our results demonstrate that modulation of the functions of a chaperone can affect signal transduction at the cell surface.

  18. Stoichiometry and geometry of the CXC chemokine receptor 4 complex with CXC ligand 12: Molecular modeling and experimental validation

    Science.gov (United States)

    Kufareva, Irina; Stephens, Bryan S.; Holden, Lauren G.; Qin, Ling; Zhao, Chunxia; Kawamura, Tetsuya; Abagyan, Ruben; Handel, Tracy M.

    2014-01-01

    Chemokines and their receptors regulate cell migration during development, immune system function, and in inflammatory diseases, making them important therapeutic targets. Nevertheless, the structural basis of receptor:chemokine interaction is poorly understood. Adding to the complexity of the problem is the persistently dimeric behavior of receptors observed in cell-based studies, which in combination with structural and mutagenesis data, suggest several possibilities for receptor:chemokine complex stoichiometry. In this study, a combination of computational, functional, and biophysical approaches was used to elucidate the stoichiometry and geometry of the interaction between the CXC-type chemokine receptor 4 (CXCR4) and its ligand CXCL12. First, relevance and feasibility of a 2:1 stoichiometry hypothesis was probed using functional complementation experiments with multiple pairs of complementary nonfunctional CXCR4 mutants. Next, the importance of dimers of WT CXCR4 was explored using the strategy of dimer dilution, where WT receptor dimerization is disrupted by increasing expression of nonfunctional CXCR4 mutants. The results of these experiments were supportive of a 1:1 stoichiometry, although the latter could not simultaneously reconcile existing structural and mutagenesis data. To resolve the contradiction, cysteine trapping experiments were used to derive residue proximity constraints that enabled construction of a validated 1:1 receptor:chemokine model, consistent with the paradigmatic two-site hypothesis of receptor activation. The observation of a 1:1 stoichiometry is in line with accumulating evidence supporting monomers as minimal functional units of G protein-coupled receptors, and suggests transmission of conformational changes across the dimer interface as the most probable mechanism of altered signaling by receptor heterodimers. PMID:25468967

  19. Stoichiometry and geometry of the CXC chemokine receptor 4 complex with CXC ligand 12: molecular modeling and experimental validation.

    Science.gov (United States)

    Kufareva, Irina; Stephens, Bryan S; Holden, Lauren G; Qin, Ling; Zhao, Chunxia; Kawamura, Tetsuya; Abagyan, Ruben; Handel, Tracy M

    2014-12-16

    Chemokines and their receptors regulate cell migration during development, immune system function, and in inflammatory diseases, making them important therapeutic targets. Nevertheless, the structural basis of receptor:chemokine interaction is poorly understood. Adding to the complexity of the problem is the persistently dimeric behavior of receptors observed in cell-based studies, which in combination with structural and mutagenesis data, suggest several possibilities for receptor:chemokine complex stoichiometry. In this study, a combination of computational, functional, and biophysical approaches was used to elucidate the stoichiometry and geometry of the interaction between the CXC-type chemokine receptor 4 (CXCR4) and its ligand CXCL12. First, relevance and feasibility of a 2:1 stoichiometry hypothesis was probed using functional complementation experiments with multiple pairs of complementary nonfunctional CXCR4 mutants. Next, the importance of dimers of WT CXCR4 was explored using the strategy of dimer dilution, where WT receptor dimerization is disrupted by increasing expression of nonfunctional CXCR4 mutants. The results of these experiments were supportive of a 1:1 stoichiometry, although the latter could not simultaneously reconcile existing structural and mutagenesis data. To resolve the contradiction, cysteine trapping experiments were used to derive residue proximity constraints that enabled construction of a validated 1:1 receptor:chemokine model, consistent with the paradigmatic two-site hypothesis of receptor activation. The observation of a 1:1 stoichiometry is in line with accumulating evidence supporting monomers as minimal functional units of G protein-coupled receptors, and suggests transmission of conformational changes across the dimer interface as the most probable mechanism of altered signaling by receptor heterodimers.

  20. SDF1 in the dorsal corticospinal tract promotes CXCR4+ cell migration after spinal cord injury

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    Jung Hosung

    2011-02-01

    Full Text Available Abstract Background Stromal cell-derived factor-1 (SDF1 and its major signaling receptor, CXCR4, were initially described in the immune system; however, they are also expressed in the nervous system, including the spinal cord. After spinal cord injury, the blood brain barrier is compromised, opening the way for chemokine signaling between these two systems. These experiments clarified prior contradictory findings on normal expression of SDF1 and CXCR4 as well as examined the resulting spinal cord responses resulting from this signaling. Methods These experiments examined the expression and function of SDF1 and CXCR4 in the normal and injured adult mouse spinal cord primarily using CXCR4-EGFP and SDF1-EGFP transgenic reporter mice. Results In the uninjured spinal cord, SDF1 was expressed in the dorsal corticospinal tract (dCST as well as the meninges, whereas CXCR4 was found only in ependymal cells surrounding the central canal. After spinal cord injury (SCI, the pattern of SDF1 expression did not change rostral to the lesion but it disappeared from the degenerating dCST caudally. By contrast, CXCR4 expression changed dramatically after SCI. In addition to the CXCR4+ cells in the ependymal layer, numerous CXCR4+ cells appeared in the peripheral white matter and in the dorsal white matter localized between the dorsal corticospinal tract and the gray matter rostral to the lesion site. The non-ependymal CXCR4+ cells were found to be NG2+ and CD11b+ macrophages that presumably infiltrated through the broken blood-brain barrier. One population of macrophages appeared to be migrating towards the dCST that contains SDF1 rostral to the injury but not towards the caudal dCST in which SDF1 is no longer present. A second population of the CXCR4+ macrophages was present near the SDF1-expressing meningeal cells. Conclusions These observations suggest that attraction of CXCR4+ macrophages is part of a programmed response to injury and that modulation of the

  1. SDF-1/CXCR4 axis induces apoptosis of human degenerative nucleus pulposus cells via the NF-κB pathway

    Science.gov (United States)

    LIU, ZONGCHAO; MA, CHUAN; SHEN, JIELIANG; WANG, DAWU; HAO, JIE; HU, ZHENMING

    2016-01-01

    Intervertebral disc degeneration (IVDD) is a major cause of lower back pain, and increased cell apoptosis is a key characteristic of IVDD. The present study aimed to investigate the effects and mechanism of the stromal cell-derived factor-1 (SDF-1)/C-X-C motif chemokine receptor 4 (CXCR4) axis on apoptosis in human degenerative nucleus pulposus cells (NPCs). The expression levels of SDF-1 and CXCR4 in human intervertebral discs (IVD) were determined using immunohistochemistry and western blot analysis. Apoptosis of primary cultured NPCs was quantified by Annexin V/propidium iodide staining following stimulation with SDF-1 and knockdown of CXCR4 using small interfering RNA (siRNA). The association with the nuclear factor-κB (NF-κB) signaling pathway was investigated using CXCR4-siRNA and NF-κB inhibitor, pyrrolidine dithiocarbamate (PDTC), treatment. The results demonstrated that SDF-1 and its receptor, CXCR4, were upregulated in degenerative IVD samples compared with normal samples. Stimulation with SDF-1 increased the level of apoptosis in cultured NPCs, and conversely, the apoptosis level was suppressed post-transfection with CXCR4 siRNA compared with SDF-1 stimulation alone. Furthermore, SDF-1 treatment increased the level of phosphorylated NF-κB subunit P65, which was downregulated following CXCR4 siRNA and PDTC treatment. In addition, CXCR4 siRNA and PDTC inhibited the nuclear translocation of P65, which was induced by SDF-1. Taken together, SDF-1-mediated apoptosis was suppressed by NF-κB inhibition using PDTC. In conclusion, the SDF-1/CXCR4 axis promoted cell apoptosis in human degenerative NPCs via the NF-κB pathway, thus suggesting that SDF-1/CXCR signaling may be a therapeutic target for the treatment of degenerative IVD diseases. PMID:27220474

  2. F-actin-binding protein drebrin regulates CXCR4 recruitment to the immune synapse.

    Science.gov (United States)

    Pérez-Martínez, Manuel; Gordón-Alonso, Mónica; Cabrero, José Román; Barrero-Villar, Marta; Rey, Mercedes; Mittelbrunn, María; Lamana, Amalia; Morlino, Giulia; Calabia, Carmen; Yamazaki, Hiroyuki; Shirao, Tomoaki; Vázquez, Jesús; González-Amaro, Roberto; Veiga, Esteban; Sánchez-Madrid, Francisco

    2010-04-01

    The adaptive immune response depends on the interaction of T cells and antigen-presenting cells at the immune synapse. Formation of the immune synapse and the subsequent T-cell activation are highly dependent on the actin cytoskeleton. In this work, we describe that T cells express drebrin, a neuronal actin-binding protein. Drebrin colocalizes with the chemokine receptor CXCR4 and F-actin at the peripheral supramolecular activation cluster in the immune synapse. Drebrin interacts with the cytoplasmic tail of CXCR4 and both proteins redistribute to the immune synapse with similar kinetics. Drebrin knockdown in T cells impairs the redistribution of CXCR4 and inhibits actin polymerization at the immune synapse as well as IL-2 production. Our data indicate that drebrin exerts an unexpected and relevant functional role in T cells during the generation of the immune response.

  3. CXCR4 Blockade Attenuates Hyperoxia Induced Lung Injury in Neonatal Rats

    Science.gov (United States)

    Drummond, Shelley; Ramachandran, Shalini; Torres, Eneida; Huang, Jian; Hehre, Dorothy; Suguihara, Cleide; Young, Karen C.

    2015-01-01

    Background Lung inflammation is a key factor in the pathogenesis of bronchopulmonary dysplasia (BPD). Stromal derived factor-1 (SDF-1) and its receptor chemokine receptor 4 (CXCR4) modulate the inflammatory response. Whether antagonism of CXCR4 will alleviate lung inflammation in neonatal hyperoxia-induced lung injury is unknown. Objective To determine whether CXCR4 antagonism would attenuate lung injury in rodents with experimental BPD by decreasing pulmonary inflammation. Methods Newborn rats exposed to normoxia (RA) or hyperoxia (FiO2=0.9) from postnatal day 2 (P2)-P16 were randomized to receive the CXCR4 antagonist, AMD3100 or placebo (PL) from P5 to P15. Lung alveolarization, angiogenesis, and inflammation were evaluated at P16. Results As compared to RA, hyperoxic-PL pups had a decrease in alveolarization, reduced lung vascular density and increased lung inflammation. In contrast, AMD3100-treated hyperoxic pups had improved alveolarization and increased angiogenesis. This improvement in lung structure was accompanied by a decrease in bronchoalveolar lavage fluid macrophage and neutrophil count and reduced lung myeloperoxidase activity. Conclusion CXCR4 antagonism decreases lung inflammation and improves alveolar as well as vascular structure in neonatal rats with experimental BPD. These findings suggest a novel therapeutic strategy to alleviate lung injury in preterm infants with BPD. PMID:25825119

  4. In vivo evolution of HIV-1 co-receptor usage and sensitivity to chemokine-mediated suppression.

    Science.gov (United States)

    Scarlatti, G; Tresoldi, E; Björndal, A; Fredriksson, R; Colognesi, C; Deng, H K; Malnati, M S; Plebani, A; Siccardi, A G; Littman, D R; Fenyö, E M; Lusso, P

    1997-11-01

    Following the identification of the C-C chemokines RANTES, MIP-1alpha and MIP-1beta as major human immunodeficiency virus (HIV)-suppressive factors produced by CD8+ T cells, several chemokine receptors were found to serve as membrane co-receptors for primate immunodeficiency lentiretroviruses. The two most widely used co-receptors thus far recognized, CCR5 and CXCR4, are expressed by both activated T lymphocytes and mononuclear phagocytes. CCR5, a specific RANTES, MIP-1alpha and MIP-1 receptor, is used preferentially by non-MT2-tropic HIV-1 and HIV-2 strains and by simian immunodeficiency virus (SIV), whereas CXCR4, a receptor for the C-X-C chemokine SDF-1, is used by MT2-tropic HIV-1 and HIV-2, but not by SIV. Other receptors with a more restricted cellular distribution, such as CCR2b, CCR3 and STRL33, can also function as co-receptors for selected viral isolates. The third variable region (V3) of the gp120 envelope glycoprotein of HIV-1 has been fingered as a critical determinant of the co-receptor choice. Here, we document a consistent pattern of evolution of viral co-receptor usage and sensitivity to chemokine-mediated suppression in a longitudinal follow-up of children with progressive HIV-1 infection. Viral isolates obtained during the asymptomatic stages generally used only CCR5 as a co-receptor and were inhibited by RANTES, MIP-1alpha and MIP-1beta, but not by SDF-1. By contrast, the majority of the isolates derived after the progression of the disease were resistant to C-C chemokines, having acquired the ability to use CXCR4 and, in some cases, CCR3, while gradually losing CCR5 usage. Surprisingly, most of these isolates were also insensitive to SDF-1, even when used in combination with RANTES. An early acquisition of CXCR4 usage predicted a poor prognosis. In children who progressed to AIDS without a shift to CXCR4 usage, all the sequential isolates were CCR5-dependent but showed a reduced sensitivity to C-C chemokines. Discrete changes in the V3 domain

  5. Fibrocyte CXCR4 regulation as a therapeutic target in pulmonary fibrosis.

    Science.gov (United States)

    Mehrad, Borna; Burdick, Marie D; Strieter, Robert M

    2009-01-01

    Fibrotic interstitial lung diseases are characterized by progressive decline in lung function and premature death from respiratory failure. Fibrocytes are circulating bone marrow-derived progenitor cells that traffic to the lungs and contribute to fibrosis and may represent novel therapeutic targets in these diseases. We have previously found the recruitment of fibrocytes to the lung to be dependent on the chemokine ligand CXCL12. Given that the expression of the CXCL12 receptor, CXCR4, can be modulated pharmacologically in other cell types, we tested the hypotheses that the regulation of CXCR4 expression on fibrocytes mediates their influx to the lung in the context of pulmonary fibrosis and that pharmacologic inhibition of this process results in attenuated disease severity. CXCR4 was the predominant chemokine receptor on human fibrocytes, and its expression on fibrocytes was enhanced by hypoxia and by growth factors including platelet-derived growth factor. Both hypoxia-induced and growth factor-induced CXCR4 expressions were attenuated by specific inhibition of PI3-kinase and mTOR. Finally, in the mouse model of bleomycin-induced pulmonary fibrosis, treatment with the mTOR inhibitor rapamycin resulted in reduced numbers of CXCR4-expressing fibrocytes in the peripheral blood and lung as well as reduced lung collagen deposition. Taken together, these experiments support the notion that pharmacologic inhibition of the CXCR4/CXCL12 biological axis is achievable in human fibrocytes and reduces the magnitude of pulmonary fibrosis in an animal model. This approach may hold promise in human fibrotic lung diseases.

  6. Chemokines and Chemokine Receptors in the Development of Lupus Nephritis

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    Xiaofeng Liao

    2016-01-01

    Full Text Available Lupus nephritis (LN is a major cause of morbidity and mortality in the patients with systemic lupus erythematosus (SLE, an autoimmune disease with damage to multiple organs. Leukocyte recruitment into the inflamed kidney is a critical step to promote LN progression, and the chemokine/chemokine receptor system is necessary for leukocyte recruitment. In this review, we summarize recent studies on the roles of chemokines and chemokine receptors in the development of LN and discuss the potential and hurdles of developing novel, chemokine-based drugs to treat LN.

  7. The HIV-1 Gp120/CXCR4 axis promotes CCR7 ligand-dependent CD4 T cell migration: CCR7 homo- and CCR7/CXCR4 hetero-oligomer formation as a possible mechanism for up-regulation of functional CCR7.

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    Haruko Hayasaka

    Full Text Available During human immunodeficiency virus (HIV infection, enhanced migration of infected cells to lymph nodes leads to efficient propagation of HIV-1. The selective chemokine receptors, including CXCR4 and CCR7, may play a role in this process, yet the viral factors regulating chemokine-dependent T cell migration remain relatively unclear. The functional cooperation between the CXCR4 ligand chemokine CXCL12 and the CCR7 ligand chemokines CCL19 and CCL21 enhances CCR7-dependent T cell motility in vitro as well as cell trafficking into the lymph nodes in vivo. In this study, we report that a recombinant form of a viral CXCR4 ligand, X4-tropic HIV-1 gp120, enhanced the CD4 T cell response to CCR7 ligands in a manner dependent on CXCR4 and CD4, and that this effect was recapitulated by HIV-1 virions. HIV-1 gp120 significantly enhanced CCR7-dependent CD4 T cell migration from the footpad of mice to the draining lymph nodes in in vivo transfer experiments. We also demonstrated that CXCR4 expression is required for stable CCR7 expression on the CD4 T cell surface, whereas CXCR4 signaling facilitated CCR7 ligand binding to the cell surface and increased the level of CCR7 homo- as well as CXCR4/CCR7 hetero-oligomers without affecting CCR7 expression levels. Our findings indicate that HIV-evoked CXCR4 signaling promotes CCR7-dependent CD4 T cell migration by up-regulating CCR7 function, which is likely to be induced by increased formation of CCR7 homo- and CXCR4/CCR7 hetero-oligomers on the surface of CD4 T cells.

  8. The HIV-1 Gp120/CXCR4 axis promotes CCR7 ligand-dependent CD4 T cell migration: CCR7 homo- and CCR7/CXCR4 hetero-oligomer formation as a possible mechanism for up-regulation of functional CCR7.

    Science.gov (United States)

    Hayasaka, Haruko; Kobayashi, Daichi; Yoshimura, Hiromi; Nakayama, Emi E; Shioda, Tatsuo; Miyasaka, Masayuki

    2015-01-01

    During human immunodeficiency virus (HIV) infection, enhanced migration of infected cells to lymph nodes leads to efficient propagation of HIV-1. The selective chemokine receptors, including CXCR4 and CCR7, may play a role in this process, yet the viral factors regulating chemokine-dependent T cell migration remain relatively unclear. The functional cooperation between the CXCR4 ligand chemokine CXCL12 and the CCR7 ligand chemokines CCL19 and CCL21 enhances CCR7-dependent T cell motility in vitro as well as cell trafficking into the lymph nodes in vivo. In this study, we report that a recombinant form of a viral CXCR4 ligand, X4-tropic HIV-1 gp120, enhanced the CD4 T cell response to CCR7 ligands in a manner dependent on CXCR4 and CD4, and that this effect was recapitulated by HIV-1 virions. HIV-1 gp120 significantly enhanced CCR7-dependent CD4 T cell migration from the footpad of mice to the draining lymph nodes in in vivo transfer experiments. We also demonstrated that CXCR4 expression is required for stable CCR7 expression on the CD4 T cell surface, whereas CXCR4 signaling facilitated CCR7 ligand binding to the cell surface and increased the level of CCR7 homo- as well as CXCR4/CCR7 hetero-oligomers without affecting CCR7 expression levels. Our findings indicate that HIV-evoked CXCR4 signaling promotes CCR7-dependent CD4 T cell migration by up-regulating CCR7 function, which is likely to be induced by increased formation of CCR7 homo- and CXCR4/CCR7 hetero-oligomers on the surface of CD4 T cells.

  9. A differential role for CXCR4 in the regulation of normal versus malignant breast stem cell activity.

    Science.gov (United States)

    Ablett, Matthew P; O'Brien, Ciara S; Sims, Andrew H; Farnie, Gillian; Clarke, Robert B

    2014-02-15

    C-X-C chemokine receptor type 4 (CXCR4) is known to regulate lung, pancreatic and prostate cancer stem cells. In breast cancer, CXCR4 signalling has been reported to be a mediator of metastasis, and is linked to poor prognosis. However its role in normal and malignant breast stem cell function has not been investigated. Anoikis resistant (AR) cells were collected from immortalised (MCF10A, 226L) and malignant (MCF7, T47D, SKBR3) breast cell lines and assessed for stem cell enrichment versus unsorted cells. AR cells had significantly higher mammosphere forming efficiency (MFE) than unsorted cells. The AR normal cells demonstrated increased formation of 3D structures in Matrigel compared to unsorted cells. In vivo, SKBR3 and T47D AR cells had 7- and 130-fold enrichments for tumour formationrespectively, compared with unsorted cells. AR cells contained significantly elevated CXCR4 transcript and protein levels compared to unsorted cells. Importantly, CXCR4 mRNA was higher in stem cell-enriched CD44+/CD24- patient-derived breast cancer cells compared to non-enriched cells. CXCR4 stimulation by its ligand SDF-1 reduced MFE of the normal breast cells lines but increased the MFE in T47D and patient-derived breast cancer cells. CXCR4 inhibition by AMD3100 increased stem cell activity but reduced the self-renewal capacity of the malignant breast cell line T47D. CXCR4+ FACS sorted MCF7 cells demonstrated a significantly increased MFE compared with CXCR4- cells. This significant increase in MFE was further demonstrated in CXCR4 over-expressing MCF7 cells which also had an increase in self-renewal compared to parental cells. A greater reduction in self-renewal following CXCR4 inhibition in the CXCR4 over-expressing cells compared with parental cells was also observed. Our data establish for the first time that CXCR4 signalling has contrasting effects on normal and malignant breast stem cell activity. Here, we demonstrate that CXCR4 signalling specifically regulates breast

  10. Type-Ⅰcannabinoid receptor mediates down-regulation of CXCR4 in astrocytes by cannabinoid HU210%Ⅰ型大麻素受体介导大麻素HU210对星型胶质细胞CXCR4水平下调

    Institute of Scientific and Technical Information of China (English)

    朱舟; 韩静; 张遐; 徐逸

    2016-01-01

    目的 探寻大麻素抑制中枢神经系统免疫反应的机制,为大麻素临床药物的合理应用提供实验依据.方法 用不同浓度的HU210刺激培养的星形胶质细胞,利用Western blot检测并比较刺激组和未刺激组细胞CXCR4蛋白水平的差异,进而用Ⅰ型大麻素受体(type-1 cannabinoid receptor,CB1R)拮抗剂AM281刺激细胞后,观察HU210对CXCR4表达的影响.结果 Western blot检测结果显示,高浓度HU210能下调星形胶质细胞CXCR4表达,AM28能阻断HU210所致的CXCR4下调.结论 HU210经由CB1R下调CXCR4,这可能是大麻发挥免疫抑制作用的机理之一.

  11. CXCR4/CXCL12 Axis in Non Small Cell Lung Cancer (NSCLC Pathologic Roles and Therapeutic Potential

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    Ori Wald, Oz M. Shapira, Uzi Izhar

    2013-01-01

    Full Text Available Lung cancer is the second most common malignancy and the leading cause of cancer-related death in the western world. Moreover, despite advances in surgery, chemotherapy and radiotherapy, the death rate from lung cancer remains high and the reported overall five-year survival rate is only 15%. Thus, novel treatments for this devastating disease are urgently needed. Chemokines, a family of 48 chemotactic cytokines interacts with their 7 transmembrane G-protein-coupled receptors, to guide immune cell trafficking in the body under both physiologic and pathologic conditions. Tumor cells, which express a relatively restricted repertoire of chemokine and chemokine receptors, utilize and manipulate the chemokine system in a manner that benefits both local tumor growth and distant dissemination. Among the 19 chemokine receptors, CXCR4 is the receptor most widely expressed by malignant tumors and whose role in tumor biology is most thoroughly studied. The chemokine CXCL12, which is the sole ligand of CXCR4, is highly expressed in primary lung cancer as well as in the bone marrow, liver, adrenal glands and brain, which are all sites for lung cancer metastasis. This review focuses on the pathologic role of the CXCR4/CXCL12 axis in NSCLC and on the potential therapeutic implication of targeting this axis for the treatment of NSCLC.

  12. Role of CXCR4 in the Pathogenesis of Acute Myeloid Leukemia

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    Amnon Peled, Sigal Tavor

    2013-01-01

    Full Text Available The Chemokine receptor CXCR4 and its ligand stromal derived factor-1 (SDF-1/CXCL12 are important players involved in cross-talk between leukemia cells and the bone marrow (BM microenvironment. CXCR4 expression is associated with poor prognosis in AML patients with and without the mutated FLT3 gene.CXCL12 which is constrictively secreted from the BM stroma and AML cells is critical for the survival and retention of AML cells within the BM. In vitro, CXCR4 antagonists were shown to inhibit the migration of AML cells in response to CXCL12. In addition, such antagonists were shown to inhibit the survival and colony forming potential of AML cells and abrogate the protective effects of stromal cells on chemotherapy-induced apoptosis in AML cells. In vivo, using immune deficient mouse models, CXCR4 antagonists were found to induce the mobilization of AML cells and progenitor cells into the circulation and enhance anti leukemic effects of chemotherapy. The hypothesis that CXCL12/CXCR4 interactions contribute to the resistance of AML cells to signal transduction inhibitor- and chemotherapy-induced apoptosis is currently being tested in a series of Phase I/II studies in humans.

  13. Emerging targets in cancer management: role of the CXCL12/CXCR4 axis

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    Cojoc M

    2013-09-01

    Full Text Available Monica Cojoc,1 Claudia Peitzsch,1 Franziska Trautmann,1 Leo Polishchuk,2 Gennady D Telegeev,2 Anna Dubrovska11OncoRay National Center for Radiation Research in Oncology, Medical Faculty Carl Gustav Carus, Dresden University of Technology, Dresden, Germany; 2Institute of Molecular Biology and Genetics, National Academy of Sciences of Ukraine, Kyiv, UkraineAbstract: The chemokine CXCL12 (SDF-1 and its cell surface receptor CXCR4 were first identified as regulators of lymphocyte trafficking to the bone marrow. Soon after, the CXCL12/CXCR4 axis was proposed to regulate the trafficking of breast cancer cells to sites of metastasis. More recently, it was established that CXCR4 plays a central role in cancer cell proliferation, invasion, and dissemination in the majority of malignant diseases. The stem cell concept of cancer has revolutionized the understanding of tumorigenesis and cancer treatment. A growing body of evidence indicates that a subset of cancer cells, referred to as cancer stem cells (CSCs, plays a critical role in tumor initiation, metastatic colonization, and resistance to therapy. Although the signals generated by the metastatic niche that regulate CSCs are not yet fully understood, accumulating evidence suggests a key role of the CXCL12/CXCR4 axis. In this review we focus on physiological functions of the CXCL12/CXCR4 signaling pathway and its role in cancer and CSCs, and we discuss the potential for targeting this pathway in cancer management.Keywords: epithelial-to-mesenchymal transition, cancer stem cells, metastasis

  14. CXCR4(+) dendritic cells promote angiogenesis during embryo implantation in mice.

    Science.gov (United States)

    Barrientos, Gabriela; Tirado-González, Irene; Freitag, Nancy; Kobelt, Peter; Moschansky, Petra; Klapp, Burghard F; Thijssen, Victor L J L; Blois, Sandra M

    2013-04-01

    Early pregnancy is characterized by decidual adaption to the developing embryo involving angiogenesis and vascular growth. Failure of decidual vascular expansion is linked to diseases of pregnancy. Dendritic cells (DC) have been associated with vascular growth during early gestation, though it is unknown whether their capacity to modulate angiogenesis is ubiquitous to all DC subsets. Here, we show that DC normally found associated with the decidual vasculature co-express the C-X-C chemokine receptor type 4 (CXCR4). In addition, we demonstrate that impaired homing of CXCR4(+)DC during early gestation provoked a disorganized decidual vasculature with impaired spiral artery remodeling later in gestation. In contrast, adoptive transfer experiments provided evidence that CXCR4(+)DC are able to rescue early pregnancy by normalizing decidual vascular growth and delivery of pro-angiogenic factors, which results in adequate remodeling of the spiral arteries during placental development. Taken together, our results indicate an important role of CXCR4(+)DC in the regulation of decidual angiogenesis and highlight the importance of the CXCL12/CXCR4 pathway during this process, suggesting that this may represent a key pathway to evaluate during pregnancy pathologies associated with impaired vascular expansion.

  15. The CXCR4/CXCR7/CXCL12 Axis Is Involved in a Secondary but Complex Control of Neuroblastoma Metastatic Cell Homing.

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    Annick Mühlethaler-Mottet

    Full Text Available Neuroblastoma (NB is one of the most deadly solid tumors of the young child, for which new efficient and targeted therapies are strongly needed. The CXCR4/CXCR7/CXCL12 chemokine axis has been involved in the progression and organ-specific dissemination of various cancers. In NB, CXCR4 expression was shown to be associated to highly aggressive undifferentiated tumors, while CXCR7 expression was detected in more differentiated and mature neuroblastic tumors. As investigated in vivo, using an orthotopic model of tumor cell implantation of chemokine receptor-overexpressing NB cells (IGR-NB8, the CXCR4/CXCR7/CXCL12 axis was shown to regulate NB primary and secondary growth, although without any apparent influence on organ selective metastasis. In the present study, we addressed the selective role of CXCR4 and CXCR7 receptors in the homing phase of metastatic dissemination using an intravenous model of tumor cell implantation. Tail vein injection into NOD-scid-gamma mice of transduced IGR-NB8 cells overexpressing CXCR4, CXCR7, or both receptors revealed that all transduced cell variants preferentially invaded the adrenal gland and typical NB metastatic target organs, such as the liver and the bone marrow. However, CXCR4 expression favored NB cell dissemination to the liver and the lungs, while CXCR7 was able to strongly promote NB cell homing to the adrenal gland and the liver. Finally, coexpression of CXCR4 and CXCR7 receptors significantly and selectively increased NB dissemination toward the bone marrow. In conclusion, CXCR4 and CXCR7 receptors may be involved in a complex and organ-dependent control of NB growth and selective homing, making these receptors and their inhibitors potential new therapeutic targets.

  16. Slit-2/Robo-1 modulates the CXCL12/CXCR4-induced chemotaxis of T cells.

    Science.gov (United States)

    Prasad, Anil; Qamri, Zahida; Wu, Jane; Ganju, Ramesh K

    2007-09-01

    Slit, which mediates its function by binding to the Roundabout (Robo) receptor, has been shown to regulate neuronal, dendritic, and leukocyte migration. However, the molecular mechanism by which the Slit/Robo complex inhibits the migration of cells is not well defined. Here, we showed that Slit-2 can inhibit the CXCL12-induced chemotaxis and transendothelial migration of T cells and monocytes. We observed that CXCR4 associates with Robo-1 and that Slit-2 treatment enhances this association with the Robo-1 receptor. Robo-1 is a single-pass transmembrane receptor whose intracellular region contains four conserved motifs designated as CC0, CC1, CC2, and CC3. Structural and functional analyses of Robo receptors revealed that interaction of the CC3 motif with the CXCR4 receptor may regulate the CXCL12-induced chemotaxis of T cells. We further characterized Slit-2-mediated inhibition of the CXCL12/CXCR4 chemotactic pathway and found that Slit-2 can block the CXCL12-induced activation of the Src and Lck kinases but not Lyn kinase. Although Slit-2 did not inhibit the CXCL12-induced activation of MAPKs, it did inhibit the Akt phosphorylation and Rac activation induced by this chemokine. Altogether, our studies indicate a novel mechanism by which the Slit/Robo complex may inhibit the CXCR4/CXCL12-mediated chemotaxis of T cells.

  17. Transfusion of CXCR4-primed endothelial progenitor cells reduces cerebral ischemic damage and promotes repair in db/db diabetic mice.

    Directory of Open Access Journals (Sweden)

    Ji Chen

    Full Text Available This study investigated the role of stromal cell-derived factor-1α (SDF-1α/CXC chemokine receptor 4 (CXCR4 axis in brain and endothelial progenitor cells (EPCs, and explored the efficacy of CXCR4 primed EPCs in treating ischemic stroke in diabetes. The db/db diabetic and db/+ mice were used in this study. Levels of plasma SDF-1α and circulating CD34+CXCR4+ cells were measured. Brain SDF-1α and CXCR4 expression were quantified at basal and after middle cerebral artery occlusion (MCAO. In in vitro study, EPCs were transfected with adenovirus carrying null (Ad-null or CXCR4 (Ad-CXCR4 followed with high glucose (HG treatment for 4 days. For pathway block experiments, cells were pre-incubated with PI3K inhibitor or nitric oxide synthase (NOS inhibitor for two hours. The CXCR4 expression, function and apoptosis of EPCs were determined. The p-Akt/Akt and p-eNOS/eNOS expression in EPCs were also measured. In in vivo study, EPCs transfected with Ad-null or Ad-CXCR4 were infused into mice via tail vein. On day 2 and 7, the cerebral blood flow, neurologic deficit score, infarct volume, cerebral microvascular density, angiogenesis and neurogenesis were determined. We found: 1 The levels of plasma SDF-1α and circulating CD34+CXCR4+ cells were decreased in db/db mice; 2 The basal level of SDF-1α and MCAO-induced up-regulation of SDF-1α/CXCR4 axis were reduced in the brain of db/db mice; 3 Ad-CXCR4 transfection increased CXCR4 expression in EPCs and enhanced EPC colonic forming capacity; 4 Ad-CXCR4 transfection prevented EPCs from HG-induced dysfunction (migration and tube formation and apoptosis via activation of PI3K/Akt/eNOS signal pathway; 4 Ad-CXCR4 transfection enhanced the efficacy of EPC infusion in attenuating infarct volume and promoting angiogenesis and neurogenesis. Our data suggest that Ad-CXCR4 primed EPCs have better therapeutic effects for ischemia stroke in diabetes than unmodified EPCs do.

  18. Pro-Inflammatory Cytokine IL-1β Up-Regulates CXC Chemokine Receptor 4 via Notch and ERK Signaling Pathways in Tongue Squamous Cell Carcinoma.

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    Yi Sun

    Full Text Available Chronic inflammation contributes to tumor development through the induction of oncogenic mutations, genomic instability, early tumor promotion, and enhanced angiogenesis. Here, we report that IL-1 receptor 1 (IL-1R1 was expressed in 40 of 41 human tongue squamous cell carcinomas (TSCC. IL-1β up-regulated the expression of CXCR4, a CXC chemokine receptor that mediates cancer growth and metastasis, at both mRNA and protein levels in Tca8113 TSCC cells. IL-1β treatment of Tca8113 cells promoted migration in response to CXCR4 ligand stromal-derived factor α (SDF-1α. The inhibition of IL-1R1 by its antagonist IL-1Ra or RNA interference significantly reversed the up-regulation of CXCR4 induced by IL-1β. IL-1R1 activation also up-regulated the expression of IL-1β itself, suggesting a positive feedback regulation of CXCR4 expression. Furthermore, IL-1β induced the activation of Notch, which was originally considered a stem cell regulator. Pharmacological inhibition of Notch signaling reversed the up-regulation of CXCR4 induced by IL-1β, suggesting that Notch signaling may be involved in the growth and metastasis of cancers via up-regulation of CXCR4. In addition, IL-1β induced the activation of extracellular signal regulated kinase (ERK and ERK inhibition decreased the up-regulation of CXCR4 induced by IL-1β, suggesting the involvement of ERK signaling in cancer metastasis. Taken together these data suggest that IL-1β and IL-1R1 promote cancer growth and metastasis by up-regulating CXCR4 expression and that CXCR4 may be a link between inflammation and cancer.

  19. 骨肉瘤血行转移与CXCR4、VEGF相关性研究%Expression levels of CXCR4 and VEGF correlate with blood-borne metastatic progression and outcome in patients with osteosarcoma

    Institute of Scientific and Technical Information of China (English)

    Feng Lin; Shuier Zheng; Zan Shen; Lina Tang; Ping Chen; Yuan jueSun; Hui Zhao; Yang Yao

    2009-01-01

    Objective:We determine whether chemokine receptor CXCR4 and vascular endothelial growth factor (VEGF) expression related to the metastasis and survival outcome of patients with osteosarcoma. Methods:Tissue microarray (TMA) was used to detect the expression of CXCR4 and VEGF in 56 osteosarcoma patient samples. Two-year follow-up was per-formed to observe the metastatic behavior and overall survival of osteosarcema patients. Results:There was a significant correlation between the expression levels of CXCR4 and VEGF in 56 osteosarcoma patient samples (P=0.002). Univariate analysis revealed the expression of CXCR4 and VEGF was not associated with age, gender and the level of ALP but as-sociated with clinical stage. Conclusion:These data raises the possibility that VEGF could regulate the levels of CXCR4 to promote the migration of tumor cells to target organs. CXCR4 and VEGF expression are highly correlated with metastatic progression in patients with osteosarcoma and their immunohistochemical expression have predictive value for the metastatic development.

  20. Up-Regulation of CCR5 and CXCR4 Expression on Human Monocytes by Interferon Gamma

    Institute of Scientific and Technical Information of China (English)

    陆韵; 刘祖强; 陈应华

    2003-01-01

    Chemokine receptors, mainly CCR5 and CXCR4, have been proved to be the important coreceptors in HIV-1 entry.HIV-1 disease progression is, in general, characterized by an initial predominance of CCR5 using macrophage tropic, non-syncytium-inducing (NSI) isolates, switching later to CXCR4 using T-cell tropic, syncytium-inducing (SI) isolates.How this shift occurs and how the shift can be controlled are still unclear.Since patients with rapid decline of T cell counts have constantly high levels of IFN-γ in the sera and lymphoid nodes, we investigated the influence of this cytokine on the expression of the HIV-1 coreceptors CCR5 and CXCR4 on the cell surfaces of human monocytic cell line U937 and promonocyte NB4.IFN-γ could intensively enhance the expression of both, while a low level of CCR5 expression was detected in two cell lines before stimulation.The results of semiquantitative RT-PCR also confirm the up-regulation.As the newly generated X4-strains have been demonstrated to be insensitive to chemokine in some reports, IFN-γ may play an important role in selecting CXCR4-used strains.

  1. Role of chemokines and their receptors in chronic lymphocytic leukemia: function in microenvironment and targeted therapy.

    Science.gov (United States)

    Han, Ting-Ting; Fan, Lei; Li, Jian-Yong; Xu, Wei

    2014-01-01

    Chemokines produced in distinct tissue microenvironments sustain migration of mature lymphocytes in lymphoglandula. Chemokine receptors expressed on chronic lymphocytic leukemia (CLL) cells regulate the migration of the leukemia cells within the bone marrow (BM), lymphoid organs in collaboration with chemokines. Chemokines form a pro-survival circuitry by regulating leukocyte trafficking, maintaining extended lymphocyte survival. Therefore, chemokines in tumor cell-microenvironment interactions represent a target for treatment of CLL. AMD3100 disrupts the CLL/microenvironment interactions and influences CXCL12/CXCR4 survival signaling. Fostamatinib, ibrutinib, and GS-1101 as B-cell receptor (BCR)-related kinase inhibitors inhibit BCR- and chemokine-receptor-signal-regulated kinase and have a good clinical response in CLL. Lenalidomide, sorafenib, and dasatinib are other additional drugs associated with chemokine in microenvironment. Inhibiting signaling through chemokine and microenvironment associated signaling are emerging as innovative therapeutic targets in CLL. In this article, we reviewed the role of chemokines in CLL microenvironment and novel therapeutics targeting CLL microenvironment.

  2. Chemokine receptors as new molecular targets for antiviral therapy.

    Science.gov (United States)

    Santoro, F; Vassena, L; Lusso, P

    2004-04-01

    Extraordinary advancements have been made over the past decade in our understanding of the molecular mechanism of human immunodeficiency virus (HIV) entry into cells. The external HIV envelope glycoprotein, gp120, sequentially interacts with two cellular receptor molecules, the CD4 glycoprotein and a chemokine receptor, such as CCR5 or CXCR4, leading to the activation of the fusogenic domain of the transmembrane viral glycoprotein, gp41, which changes its conformation to create a hairpin structure that eventually triggers fusion between the viral and cellular membranes. Each of these discrete steps in the viral entry process represents a potential target for new antiviral agents. Current efforts to develop safe and effective HlV entry inhibitors are focused on naturally occurring proteins (e.g., chemokines, antibodies), engineered or modified derivatives of natural proteins (e.g., multimerized soluble CD4, gp41--or chemokine--derived synthetic peptides), as well as small synthetic compounds obtained either by high-throughput screening of large compound libraries or by structure-guided rational design. The recent introduction in therapy of the first fusion inhibitor, the gp41-derived synthetic peptide T20, heralds a new era in the treatment of AIDS, which will hopefully lead to more effective multi-drug regimens with reduced adverse effects for the patients.

  3. Extracellular Disulfide Bridges Serve Different Purposes in Two Homologous Chemokine Receptors, CCR1 and CCR5

    DEFF Research Database (Denmark)

    Rummel, Pia Cwarzko; Thiele, Stefanie; Hansen, Laerke Smidt

    2013-01-01

    In addition to the 7TM receptor-conserved disulfide bridge between transmembrane helix (TM) 3 and extracellular loop (ECL) 2, chemokine receptors contain a disulfide bridge between the N-terminus and what previously was believed to be ECL-3. Recent crystal- and NMR-structures of CXCR4 and CXCR1...... where dispensable for small-molecule activation. This indicates that CCR5 activity is independent of extracellular regions, whereas in CCR1, preserved folding of ECL2 is necessary for activation. These results indicate that conserved structural features in a receptor subgroup, does not necessarily...

  4. The HIF-1α/CXCR4 pathway supports hypoxia-induced metastasis of human osteosarcoma cells.

    Science.gov (United States)

    Guan, Guofeng; Zhang, Yinglong; Lu, Yao; Liu, Lijuan; Shi, Doufei; Wen, Yanhua; Yang, Lianjia; Ma, Qiong; Liu, Tao; Zhu, Xiaodong; Qiu, Xiuchun; Zhou, Yong

    2015-02-01

    HIF-1α mediates hypoxia-induced expression of the chemokine receptor CXCR4 and contributes to metastasis in many different cancers. We have previously shown that hypoxia promotes migration of human osteosarcoma cells by activating the HIF-1α/CXCR4 pathway. Here, immunohistochemical analysis showed that unlike control osteochondroma samples, osteosarcoma specimens were characterized by elevated expression levels of HIF-1α and CXCR4. Moreover, we found that hypoxia-induced invasiveness was more pronounced in high metastatic potential F5M2 osteosarcoma cells than in low metastatic potential F4 cells, and that this induction was sensitive to treatment with the CXCR4 antagonist AMD3100 and the HIF-1α inhibitor KC7F2. Interestingly, hypoxia-induced CXCR4 expression persisted after cultured osteosarcoma cells were returned to normoxic conditions. These observations were confirmed by experiments in a mouse model of osteosarcoma lung metastasis showing that hypoxia stimulation of pulmonary metastasis was greater in F5M2 than in F4 cells, and was sensitive to treatment with AMD3100. Our study provides further evidence of the contributions of hypoxia and the HIF-1α/CXCR4 pathway to the progression of osteosarcoma, and suggests that this axis might be efficiently leveraged in the development of novel osteosarcoma therapeutics. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  5. HIV-1 Nef down-modulates C-C and C-X-C chemokine receptors via ubiquitin and ubiquitin-independent mechanism.

    Directory of Open Access Journals (Sweden)

    Prabha Chandrasekaran

    Full Text Available Human and Simian Immunodeficiency virus (HIV-1, HIV-2, and SIV encode an accessory protein, Nef, which is a pathogenesis and virulence factor. Nef is a multivalent adapter that dysregulates the trafficking of many immune cell receptors, including chemokine receptors (CKRs. Physiological endocytic itinerary of agonist occupied CXCR4 involves ubiquitinylation of the phosphorylated receptor at three critical lysine residues and dynamin-dependent trafficking through the ESCRT pathway into lysosomes for degradation. Likewise, Nef induced CXCR4 degradation was critically dependent on the three lysines in the C-terminal -SSLKILSKGK- motif. Nef directly recruits the HECT domain E3 ligases AIP4 or NEDD4 to CXCR4 in the resting state. This mechanism was confirmed by ternary interactions of Nef, CXCR4 and AIP4 or NEDD4; by reversal of Nef effect by expression of catalytically inactive AIP4-C830A mutant; and siRNA knockdown of AIP4, NEDD4 or some ESCRT-0 adapters. However, ubiquitinylation dependent lysosomal degradation was not the only mechanism by which Nef downregulated CKRs. Agonist and Nef mediated CXCR2 (and CXCR1 degradation was ubiquitinylation independent. Nef also profoundly downregulated the naturally truncated CXCR4 associated with WHIM syndrome and engineered variants of CXCR4 that resist CXCL12 induced internalization via an ubiquitinylation independent mechanism.

  6. Structure of the CCR5 Chemokine Receptor-HIV Entry Inhibitor Maraviroc Complex

    Energy Technology Data Exchange (ETDEWEB)

    Tan, Qiuxiang; Zhu, Ya; Li, Jian; Chen, Zhuxi; Han, Gye Won; Kufareva, Irina; Li, Tingting; Ma, Limin; Fenalti, Gustavo; Li, Jing; Zhang, Wenru; Xie, Xin; Yang, Huaiyu; Jiang, Hualiang; Cherezov, Vadim; Liu, Hong; Stevens, Raymond C.; Zhao, Qiang; Wu, Beili [Scripps; (Chinese Aca. Sci.); (UCSD)

    2013-10-21

    The CCR5 chemokine receptor acts as a co-receptor for HIV-1 viral entry. Here we report the 2.7 angstrom–resolution crystal structure of human CCR5 bound to the marketed HIV drug maraviroc. The structure reveals a ligand-binding site that is distinct from the proposed major recognition sites for chemokines and the viral glycoprotein gp120, providing insights into the mechanism of allosteric inhibition of chemokine signaling and viral entry. A comparison between CCR5 and CXCR4 crystal structures, along with models of co-receptor–gp120-V3 complexes, suggests that different charge distributions and steric hindrances caused by residue substitutions may be major determinants of HIV-1 co-receptor selectivity. These high-resolution insights into CCR5 can enable structure-based drug discovery for the treatment of HIV-1 infection.

  7. Downregulation of CXCR4 by SDF-KDEL in SBC-5 cells inhibits their migration in vitro and organ metastasis in vivo.

    Science.gov (United States)

    Ma, Ningqiang; Pang, Hailin; Shen, Weiwei; Zhang, Feng; Cui, Zaoxun; Wang, Junyan; Wang, Jianlin; Liu, Lili; Zhang, Helong

    2015-02-01

    Metastasis is the principal cause of morbidity and mortality in cancer patients. The master genes that govern organ-selective metastasis remain elusive. We compared the expression levels of C-X-C chemokine receptor type 4 (CXCR4) in the human small cell lung cancer (SCLC) cells, SBC-5 and SBC-3, by flow cytometric analysis and found that CXCR4 was expressed at markedly higher levels in the SBC-5 cells which can produce multiple organ metastasis, particularly bone metastasis compared to the SBC-3 cells. Stromal-derived-factor-1 (SDF-1)-CXCR4 has been shown to regulate cell migration and metastasis in a various types of cancer; however, the roles of SDF-1-CXCR4 in the organ-selective metastasis of SCLC in vivo remain to be elucidated. Thus, in this study, we constructed a phenotype of SBC-5 cells in which CXCR4 was knocked out using the intrakine strategy and found that the downregulation of CXCR4 inhibited cell migration and invasion, but did not affect cell proliferation or apoptosis in vitro. In in vivo experiments, the knockout of CXCR4 suppressed the development of metastastic lesions in the lungs, liver and bone, but did not decrease metastasis to the kidneys. Our data demonstrate that CXCR4 is a candidate gene involved in the development of metastastic lesions in specific organs, such as the lungs, bone and liver, which can secrete high concentrations of SDF-1, the sole ligand of CXCR4. Thus, CXCR4 may prove to be a promising target for the prevention and effective treatment of metastastic lesions due to SCLC.

  8. Involvement of the CXCR7/CXCR4/CXCL12 axis in the malignant progression of human neuroblastoma.

    Directory of Open Access Journals (Sweden)

    Julie Liberman

    Full Text Available Neuroblastoma (NB is a typical childhood and heterogeneous neoplasm for which efficient targeted therapies for high-risk tumors are not yet identified. The chemokine CXCL12, and its receptors CXCR4 and CXCR7 have been involved in tumor progression and dissemination. While CXCR4 expression is associated to undifferentiated tumors and poor prognosis, the role of CXCR7, the recently identified second CXCL12 receptor, has not yet been elucidated in NB. In this report, CXCR7 and CXCL12 expressions were evaluated using a tissue micro-array including 156 primary and 56 metastatic NB tissues. CXCL12 was found to be highly associated to NB vascular and stromal structures. In contrast to CXCR4, CXCR7 expression was low in undifferentiated tumors, while its expression was stronger in matured tissues and specifically associated to differentiated neural tumor cells. As determined by RT-PCR, CXCR7 expression was mainly detected in N-and S-type NB cell lines, and was slightly induced upon NB cell differentiation in vitro. The relative roles of the two CXCL12 receptors were further assessed by overexpressing CXCR7 or CXCR4 receptor alone, or in combination, in the IGR-NB8 and the SH-SY5Y NB cell lines. In vitro functional analyses indicated that, in response to their common ligand, both receptors induced activation of ERK1/2 cascade, but not Akt pathway. CXCR7 strongly reduced in vitro growth, in contrast to CXCR4, and impaired CXCR4/CXCL12-mediated chemotaxis. Subcutaneous implantation of CXCR7-expressing NB cells showed that CXCR7 also significantly reduced in vivo growth. Moreover, CXCR7 affected CXCR4-mediated orthotopic growth in a CXCL12-producing environment. In such model, CXCR7, in association with CXCR4, did not induce NB cell metastatic dissemination. In conclusion, the CXCR7 and CXCR4 receptors revealed specific expression patterns and distinct functional roles in NB. Our data suggest that CXCR7 elicits anti-tumorigenic functions, and may act as a

  9. Selective loss of chemokine receptor expression on leukocytes after cell isolation.

    Directory of Open Access Journals (Sweden)

    Juan C Nieto

    Full Text Available Chemokine receptors are distinctively exposed on cells to characterize their migration pattern. However, little is known about factors that may regulate their expression. To determine the optimal conditions for an accurate analysis of chemokine receptors, we compared the expression of CCR2, CCR4, CCR5, CCR6, CXCR3 and CXCR4 on different leukocyte subsets using whole blood (WB plus erythrocyte lysis and density gradient isolation (Ficoll. Most WB monocytes were CCR2+ (93.5 ± 2.9% whereas 32.8 ± 6.0% of monocytes from Ficoll-PBMC expressed CCR2 (p<0.001. Significant reductions of CCR6 and CXCR3 on monocytes were also observed after Ficoll isolation (WB: 46.4 ± 7.5% and 57.1 ± 5.5%; Ficoll: 29.5 ± 2.2% and 5.4 ± 4.3% respectively (p<0.01. Although comparable percentages of WB and Ficoll-PBMC monocytes expressed CCR4, CCR5 and CXCR4, Ficoll isolation significantly reduced the levels of CXCR4 (WB: MFI 5 ± 0.4 and Ficoll: MFI 3.3 ± 0.1 (p<0.05. Similarly to monocytes, CCR2, CXCR3 and CXCR4 were also reduced on lymphocytes. In addition, Ficoll isolation significantly reduced the percentage of CCR4 positive lymphocytes (WB: 90.2 ± 4.5% and Ficoll: 55 ± 4.1% (p<0.01. The loss of expression of chemokine receptors after isolation of monocytes was not dependent on either the anticoagulant or the density gradient method. It was irreversible and could not be restored by LPS activation or in vitro macrophage differentiation. Experiments tagged with anti-CCR2 antibodies prior to density gradient isolation demonstrated that Ficoll internalized chemokine receptors. The method for cell isolation may alter not only the expression of certain chemokine receptors but also the respective functional migration assay. The final choice to analyze their expression should therefore depend on the receptor to be measured.

  10. Expression of CXCR4 and CXCL12 and their correlations to the cell proliferation and angiogenesis in mycosis fungoides

    Science.gov (United States)

    Maj, Joanna; Hałoń, Agnieszka; Woźniak, Zbigniew; Plomer-Niezgoda, Ewa; Reich, Adam

    2015-01-01

    Introduction Chemokines play an important role in tumor growth, invasion and metastasis. The CXCR4/CXCL12 axis has been implicated in development of both solid tumors and hematological malignancies and is also relevant in the pathogenesis of the most common primary cutaneous T-cell lymphoma, mycosis fungoides (MF). Aim To evaluate the expression of CXCR4 and CXCL12 in MF and to examine their associations with cell proliferation and angiogenesis. Material and methods The material for the study consisted of skin samples obtained from 56 patients with MF and 20 healthy volunteers. The expression of CXCR4 and CXCL12 was assessed by immunohistochemistry on the paraffin blocks and compared to the expression of angiogenesis marker (CD34) and proliferation indicators (Ki-67, AgNORs). Results The expression of chemokine CXCL12 and its receptor CXCR4 was significantly higher in MF than in the healthy skin (p < 0.001). There was no significant difference between early and advanced stages of MF. Similarly, there was no statistically important correlation between the expression of CXCR4/CXCL12 and angiogenesis and proliferation markers, however a significant correlation between CD34 and AgNORs expression was found (p < 0.001). Conclusions The CXCR4/CXCL12 axis seems to play an important role in MF development in the early as well as in the advanced stages of the disease. Therefore, the CXCR4/CXCL12 axis seems to be an interesting potential target for the future strategies of new drug development, giving hope for more efficacious therapies for mycosis fungoides. PMID:26755907

  11. Structure prediction of GPCRs using piecewise homologs and application to the human CCR5 chemokine receptor: validation through agonist and antagonist docking.

    Science.gov (United States)

    Arumugam, Karthik; Crouzy, Serge; Chevigne, Andy; Seguin-Devaux, Carole; Schmit, Jean-Claude

    2014-01-01

    This article describes the construction and validation of a three-dimensional model of the human CC chemokine receptor 5 (CCR5) receptor using multiple homology modeling. A new methodology is presented where we built each secondary structural model of the protein separately from distantly related homologs of known structure. The reliability of our approach for G-protein coupled receptors was assessed through the building of the human C-X-C chemokine receptor type 4 (CXCR4) receptor of known crystal structure. The models are refined using molecular dynamics simulations and energy minimizations using CHARMM, a classical force field for proteins. Finally, docking models of both the natural agonists and the antagonists of the receptors CCR5 and CXCR4 are proposed. This study explores the possible binding process of ligands to the receptor cavity of chemokine receptors at molecular and atomic levels. We proposed few crucial residues in receptors binding to agonist/antagonist for further validation through experimental analysis. In particular, our study provides better understanding of the blockage mechanism of the chemokine receptors CCR5 and CXCR4, and may help the identification of new lead compounds for drug development in HIV infection, inflammatory diseases, and cancer metastasis.

  12. 趋化因子SDF-1及其受体CXCR4与乳腺癌研究进展

    Institute of Scientific and Technical Information of China (English)

    娄广媛; 陈金麟; 张沂平

    2008-01-01

    近年来,趋化因子SDF—1(stromal cell—derived factor-1)及受体CXCR4(CXC chemokine receptor-4)相互作用形成的反应轴SDF-1/CXCR4在肿瘤侵袭和转移中的作用越来越受到人们的关注。Muller研究发现在乳腺癌常见转移部位高表达CXCR4与其配体SDF-1,提示SDF-1/CXCR4可能与乳腺癌发生发展有密切关系,也可能成为乳腺癌治疗的一个新靶点,改善乳腺癌患者的治疗效果。

  13. HuR-targeted nanotherapy in combination with AMD3100 suppresses CXCR4 expression, cell growth, migration, and invasion in lung cancer

    Science.gov (United States)

    Muralidharan, Ranganayaki; Panneerselvam, Janani; Chen, Allshine; Zhao, Yan Daniel; Munshi, Anupama; Ramesh, Rajagopal

    2015-01-01

    The CXCR4 chemokine receptor plays an important role in cancer cell metastasis. The CXCR4 antagonist, AMD3100, has limited efficacy in controlling metastasis. HuR, an RNA-binding protein, regulates CXCR4 in cancer cells. We therefore investigated whether targeting HuR using a siRNA-based nanoparticle plus AMD3100 would suppress CXCR4 and inhibit lung cancer metastasis. We treated human H1299 lung cancer cell with HuR-specific siRNA contained in a folate-targeted lipid nanoparticle (HuR-FNP) plus AMD3100, and compared this with AMD3100 alone, HuR-FNP alone and no treatment. HuR-FNP plus AMD3100 treatment produced a G1 phase cell-cycle arrest and reduced cell viability above and beyond the effects of AMD3100 alone. HuR and CXCR4 mRNA and protein expression levels were markedly reduced in all treatment groups. Phosphorylated (p) AKTS473 protein was also reduced. P27 protein expression increased with HuR-FNP and combination treatment. Promoter-based reporter studies showed that the combination inhibited CXCR4 promoter activity more than did either treatment alone. Cell migration and invasion was significantly reduced with all treatment; the combination provided the most inhibition. Reduced matrix metalloprotease (MMP) -2 and -9 expression was associated with reduced invasion in all treatment groups. Thus, we found that combined HuR and CXCR4 targeting effectively controlled lung cancer metastasis. PMID:26494555

  14. HuR-targeted nanotherapy in combination with AMD3100 suppresses CXCR4 expression, cell growth, migration and invasion in lung cancer.

    Science.gov (United States)

    Muralidharan, R; Panneerselvam, J; Chen, A; Zhao, Y D; Munshi, A; Ramesh, R

    2015-12-01

    The CXCR4 chemokine receptor has an important role in cancer cell metastasis. The CXCR4 antagonist, AMD3100, has limited efficacy in controlling metastasis. HuR, an RNA-binding protein, regulates CXCR4 in cancer cells. We therefore investigated whether targeting HuR using a siRNA-based nanoparticle plus AMD3100 would suppress CXCR4 and inhibit lung cancer metastasis. We treated human H1299 lung cancer cells with HuR-specific siRNA contained in a folate-targeted lipid nanoparticle (HuR-FNP) plus AMD3100, and compared this with AMD3100 alone, HuR-FNP alone and no treatment. HuR-FNP plus AMD3100 treatment produced a G1 phase cell cycle arrest and reduced cell viability above and beyond the effects of AMD3100 alone. HuR and CXCR4 mRNA and protein expression levels were markedly reduced in all treatment groups. Phosphorylated (p) AKT(S473) protein was also reduced. P27 protein expression increased with HuR-FNP and combination treatment. Promoter-based reporter studies showed that the combination inhibited CXCR4 promoter activity more than did either treatment alone. Cell migration and invasion was significantly reduced with all treatments; the combination provided the most inhibition. Reduced matrix metalloprotease (MMP)-2 and -9 expression was associated with reduced invasion in all treatment groups. Thus, we found that combined HuR and CXCR4 targeting effectively controlled lung cancer metastasis.

  15. Reprogramming antitumor immunity against chemoresistant ovarian cancer by a CXCR4 antagonist-armed viral oncotherapy

    Directory of Open Access Journals (Sweden)

    Marcin P Komorowski

    2016-01-01

    Full Text Available Ovarian cancer remains the most lethal gynecologic malignancy owing to late detection, intrinsic and acquired chemoresistance, and remarkable heterogeneity. Here, we explored approaches to inhibit metastatic growth of murine and human ovarian tumor variants resistant to paclitaxel and carboplatin by oncolytic vaccinia virus expressing a CXCR4 antagonist to target the CXCL12 chemokine/CXCR4 receptor signaling axis alone or in combination with doxorubicin. The resistant variants exhibited augmented expression of the hyaluronan receptor CD44 and CXCR4 along with elevated Akt and ERK1/2 activation and displayed an increased susceptibility to viral infection compared with the parental counterparts. The infected cultures were more sensitive to doxorubicin-mediated killing both in vitro and in tumor-challenged mice. Mechanistically, the combination treatment increased apoptosis and phagocytosis of tumor material by dendritic cells associated with induction of antitumor immunity. Targeting syngeneic tumors with this regimen increased intratumoral infiltration of antitumor CD8+ T cells. This was further enhanced by reducing the immunosuppressive network by the virally-delivered CXCR4 antagonist, which augmented antitumor immune responses and led to tumor-free survival. Our results define novel strategies for treatment of drug-resistant ovarian cancer that increase immunogenic cell death and reverse the immunosuppressive tumor microenvironment, culminating in antitumor immune responses that control metastatic tumor growth.

  16. Lipopolysaccharide Promotes Choroidal Neovascularization by Up-Regulation of CXCR4 and CXCR7 Expression in Choroid Endothelial Cell.

    Directory of Open Access Journals (Sweden)

    Yi-fan Feng

    Full Text Available Stromal cell-derived factor-1 (SDF-1 has been confirmed to participate in the formation of choroidal neovascularization (CNV via its two receptors: CXC chemokine receptors 4 (CXCR4 and CXCR7. Previous studies have indicated that the activation of Toll-like receptors (TLRs by lipopolysaccharide (LPS might elevate CXCR4 and/or CXCR7 expression in tumor cells, enhancing the response to SDF-1 to promote invasion and cell dissemination. However, the impact of LPS on the CXCR4 and CXCR7 expression in endothelial cells and subsequent pathological angiogenesis formation remains to be elucidated. The present study shows that LPS enhanced the CXCR4 and CXCR7 expression via activation of the TLR4 pathway in choroid-retinal endothelial (RF/6A cells. In addition, the transcriptional regulation of CXCR4 and CXCR7 by LPS was found to be mediated by phosphorylation of the extracellular signal-related kinase (ERK 1/2 and activation of nuclear factor kappa B (NF-κB signaling pathways, which were blocked by ERK- or NF-κB-specific inhibitors. Furthermore, the increased CXCR4 and CXCR7 expression resulted in increased SDF-1-induced RF/6A cells proliferation, migration and tube formation. In vivo, LPS-treated rat had significantly higher mRNA levels of CXCR4 and CXCR7 expression and lager laser-induced CNV area than vehicle-treated rat. SDF-1 blockade with a neutralizing antibody attenuated the progression of CNV in LPS-treated rat after a single intravitreal injection. Altogether, these results demonstrated that LPS might influence CNV formation by enhancing CXCR7 and CXCR7 expression in endothelial cells, possibly providing a new perspective for the treatment of CNV-associated diseases.

  17. Progress of SDF-1/CXCR4 and Hypertensive Disorder Complicating Pregnancy%SDF-1/CXCR4与妊娠期高血压疾病关系的研究进展

    Institute of Scientific and Technical Information of China (English)

    朱小华; 罗新

    2015-01-01

    Stromal cell derived factor 1 (SDF-1) is only physiological ligand of CXC chemokine receptor 4 (CXCR4). CXCR4 can specifically bind to SDF-1 formed a SDF-1/CXCR4 biological axis, thus completing the corresponding biological effects. SDF-1 and its receptor CXCR4 plays an important role in physiological and pathological processes in the body. A large number of studies show that the roles of SDF-1/CXCR4 in immunity and inflammation, embryo development, activation of anti-apoptotic pathways, hematopoietic stem cell migration, homing, regulation of angiogenesis, hypertensive disorder complicating pregnancy (HDCP), preeclampsia and other biological processes have become a hot spot in biological research. In normal pregnancy, the formed of placenta played a decisive role, so the study on the expression of SDF-1/CXCR4 in the placental bed HDCP will provide a way to explore the possible pathogenesis of HDCP. Bad blood vessel formation process of erosion in trophoblast cells and bad remodeling of the spiral arteries in cell and irregular anti-apoptosis ability exceptions are the key causes of HDCP. Research shows that the decreased of SDF-1/CXCR4 in pregnant women with preeclampsia′s placenta bed has a significant incidence of hypertensive disorder complicating pregnancy. This article reviews SDF-1 and CXCR4′s research progress in hypertensive disorders in pregnancy.%基质细胞衍生因子1(SDF-1)是CXC族趋化因子受体4(CXCR4)的唯一生理学配体,CXCR4可与SDF-1特异性结合形成SDF-1/CXCR4生物轴,从而完成相应的生物学效应。 SDF-1与其受体CXCR4在机体的生理和病理过程中发挥着重要的作用。 SDF-1/CXCR4在机体的免疫炎症、胚胎发育、激活抗调亡途径、造血干细胞迁移、归巢、调控血管生成及妊娠期高血压疾病(HDCP)、子痫前期等多种生物学过程中的作用受到关注,已成为当今生物学研究的热点之一。在正常的妊娠过程中,胎盘形成起

  18. 基质细胞衍生因子1α及其受体CXCR4在牙本质-牙髓复合体损伤修复过程中的表达%The expression of stromal cell derived factor 1 a and its receptor CXCR4 in injured dentin-dental pulp

    Institute of Scientific and Technical Information of China (English)

    栗世洋; 张莹; 齐春子; 张云松; 余擎

    2011-01-01

    目的:通过构建牙本质-牙髓复合体损伤修复动物模型,研究基质细胞衍生因子1α 及其受体CXCR4(SDF-1α /CXCR4)在其损伤修复过程中的表达.方法:制备大鼠牙本质-牙髓损伤模型,通过免疫组织化学染色、PCR技术分别对损伤后0、6 h和1、3、7 d及正常大鼠牙髓标本中SDF-1α /CXCR4进行检测.结果:正常大鼠组牙髓中没有发现SDF-1α 、CXCR4阳性表达,实验大鼠组损伤6 h后少量的成牙本质细胞和前期牙本质开始出现较弱阳性表达,损伤1 d后成牙本质细胞阳性表达增强,损伤3 d后牙髓成纤维细胞出现阳性表达,损伤7 d后未分化间充质细胞出现阳性表达,大鼠牙髓损伤后SDF-1α 、CXCR4随着时间的增加阳性表达程度明显增强.图像分析结果显示,SD大鼠牙本质-牙髓复合体损伤后牙髓中SDF-1α 、CXCR4的表达(灰度值)除0 h外其余各组均高于对照组(P<0.05).PCR结果显示,损伤后大鼠牙髓中SDF-1α 、CXCR4均符合产物设计大小.其表达(灰度值)除0 h外其余各组均高于对照组(P<0.05).结论:大鼠牙本质-牙髓复合体损伤后,前期牙本质、成牙本质细胞、牙髓成纤维细胞和未分化间充质细胞对SDF-1α 、CXCR4的表达呈时间依赖性,提示SDF-1α 、CXCR4可能参与了修复性牙本质的形成.%AIM : To investigate the expression and effect of stomal ceU derived factor 1 alpha ( SDF-1α) and its receptor CXCR4 in the rehabilitation process of dentin-dental pulp injury by establishing an arumal model of dentin-dental pulp injury rehabilitation.MEIHODS: A rat model of dental pulp-dentin injury was established.SDF-Ia and CXCR4 expression in dental pulp samples at the moment of O h, 6 h, 1 d, 3 d, 7 d after injury and in normal pulp was detected by immunohiscochemical staining (IHC) and RT-PCR.RESULTS : No positive staining of SDF-1α and CXCR4 was detected in normal dental pulp samples by IHC.6 h after injury, weak expression of SDF-Ia and CXCR4

  19. pVHL co-ordinately regulates CXCR4/CXCL12 and MMP2/MMP9 expression in human clear-cell renal cell carcinoma

    DEFF Research Database (Denmark)

    Struckmann, K; Mertz, Kd; Steu, S;

    2008-01-01

    Loss of pVHL function, characteristic for clear-cell renal cell carcinoma (ccRCC), causes increased expression of CXCR4 chemokine receptor, which triggers expression of metastasis-associated MMP2/MMP9 in different human cancers. The impact of pVHL on MMP2/MMP9 expression and their relationship...

  20. CXCL12 chemokine and its receptors as major players in the interactions between immune and nervous systems

    Directory of Open Access Journals (Sweden)

    Alice eGuyon

    2014-03-01

    Full Text Available The chemokine CXCL12/SDF1a has first been described in the immune system where it functions include chemotaxis for lymphocytes and macrophages, migration of hematopoietic cells from fetal liver to bone marrow and the formation of large blood vessels. Among other chemokines, CXCL12 has recently attracted much attention in the brain as it has been shown that it can be produced not only by glial cells but also by neurons. In addition, its receptors CXCR4 and CXCR7, which are belonging to the G-protein coupled receptors family, are abundantly expressed in diverse brain area, CXCR4 being a major co-receptor for human immunodeficiency virus (HIV-1 entry. This chemokine system has been shown to play important roles in brain plasticity processes occurring during development but also in the physiology of the brain in normal and pathological conditions. For example, in neurons, CXCR4 stimulation has been shown regulate the synaptic release of glutamate and GABA. It can also act post-synaptically by activating a G-protein Inward Rectifier K+ (GIRK, a voltage-gated K channel Kv2.1 associated to neuronal survival, and by increasing high voltage activated (HVA Ca2+ currents. In addition, it has been recently evidenced that there are several crosstalks between the CXCL12/CXCR4-7 system and other neurotransmitter systems in the brain (such as GABA, glutamate, opioids ans cannabinoids. Overall, this chemokine system could be one of the key players of the neuro-immune interface that participates in shaping the brain in response to changes in the environment.

  1. Dynamic Cholesterol-Conditioned Dimerization of the G Protein Coupled Chemokine Receptor Type 4.

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    Kristyna Pluhackova

    2016-11-01

    Full Text Available G protein coupled receptors (GPCRs allow for the transmission of signals across biological membranes. For a number of GPCRs, this signaling was shown to be coupled to prior dimerization of the receptor. The chemokine receptor type 4 (CXCR4 was reported before to form dimers and their functionality was shown to depend on membrane cholesterol. Here, we address the dimerization pattern of CXCR4 in pure phospholipid bilayers and in cholesterol-rich membranes. Using ensembles of molecular dynamics simulations, we show that CXCR4 dimerizes promiscuously in phospholipid membranes. Addition of cholesterol dramatically affects the dimerization pattern: cholesterol binding largely abolishes the preferred dimer motif observed for pure phospholipid bilayers formed mainly by transmembrane helices 1 and 7 (TM1/TM5-7 at the dimer interface. In turn, the symmetric TM3,4/TM3,4 interface is enabled first by intercalating cholesterol molecules. These data provide a molecular basis for the modulation of GPCR activity by its lipid environment.

  2. CXCR4-mediated osteosarcoma growth and pulmonary metastasis is promoted by mesenchymal stem cells through VEGF.

    Science.gov (United States)

    Zhang, Peng; Dong, Ling; Yan, Kang; Long, Hua; Yang, Tong-Tao; Dong, Ming-Qing; Zhou, Yong; Fan, Qing-Yu; Ma, Bao-An

    2013-10-01

    Chemokines and chemokine receptor 4 (CXCR4) play an important role in metastasis. CXCR4 is also expressed in the human osteosarcoma cell line 9607-F5M2 (F5M2), which has a high tumorigenic ability and potential for spontaneous pulmonary metastasis. Mesenchymal stem cells (MSCs) contribute to the formation of the tumor stroma and promote metastasis. However, mechanisms underlying the promotion of osteosarcoma growth and pulmonary metastasis by MSCs are still elusive. Our study co-injected the human MSCs and F5M2 cells into the caudal vein of nude mice. The total number of tumor nodules per lung was significantly increased in the F5M2+MSC group compared to the other groups (control, F5M2 cells alone and MSCs alone) at week six. Moreover, a high number of Dil-labeled MSCs was present also at the osteosarcoma metastasis sites in the lung. Using Transwell assays, we found that F5M2 cells migrate towards MSCs, while the CXCR4 inhibitor AMD3100 decreased the migration potential of F5M2 cells towards MSCs. Furthermore, upon treatment with F5M2-conditioned medium, MSCs expressed and secreted higher levels of VEGF as determined by immunohistochemistry, western blotting and ELISA, respectively. Importantly, co-cultured with F5M2 cells, MSCs expressed and secreted higher VEGF levels, while AMD3100 dramatically decreased the VEGF secretion by MSCs. However, CXCR4 expression on F5M2 cells was not significantly increased in the co-culture system. Additionally, VEGF increased the proliferation of both MSCs and F5M2 cells. These findings suggest that CXCR4-mediated osteosarcoma growth and pulmonary metastasis are promoted by MSCs through VEGF.

  3. Expression of CD134 and CXCR4 mRNA in term placentas from FIV-infected and control cats.

    Science.gov (United States)

    Scott, Veronica L; Burgess, Shane C; Shack, Leslie A; Lockett, Nikki N; Coats, Karen S

    2008-05-15

    Feline immunodeficiency virus (FIV) causes a natural infection of domestic cats that resembles HIV-1 in pathogenesis and disease progression. Feline AIDS is characterized by depression of the CD4+ T cell population and fatal opportunistic infections. Maternal-fetal transmission of FIV readily occurs under experimental conditions, resulting in infected viable kittens and resorbed or arrested fetal tissues. Although both FIV and HIV use the chemokine receptor CXCR4 as a co-receptor, FIV does not utilize CD4 as the primary receptor. Rather, CD134 (OX40), a T cell activation antigen and co-stimulatory molecule, is the primary receptor for FIV. We hypothesized that placental expression of CD134 and CXCR4 may render the placenta vulnerable to FIV infection, possibly facilitating efficient vertical transmission of FIV, and impact pregnancy outcome. The purpose of this project was to quantify the relative expression of CD134 and CXCR4 mRNA from the term placentas of three groups of cats: uninfected queens producing viable offspring, experimentally-infected queens producing only viable offspring, and experimentally-infected queens producing viable offspring among mostly non-viable fetuses. Total RNA was extracted from term placental tissues from all groups of cats. Real-time one-step reverse transcriptase-PCR was used to measure gene expression. The FIV receptors CD134 and CXCR4 were expressed in all late term feline placental tissues. Placentas from FIV-infected queens producing litters of only viable offspring expressed more CD134 and CXCR4 mRNA than those from uninfected queens, suggesting that infection may cause upregulation of the receptors. On the other hand, placentas from FIV-infected cats with non-successful pregnancies expressed similar levels of CD134 mRNA and slightly less CXCR4 mRNA than those from uninfected queens. Thus, it appears that cells expressing these receptors may play a role in pregnancy maintenance.

  4. Research on expression of CXCR4 and CCR7 in non small cell lung cancer cells%CXCR4、CCR7在非小细胞肺癌中表达的差异及意义

    Institute of Scientific and Technical Information of China (English)

    李醒; 温剑虎; 曾涛

    2008-01-01

    目的 探讨非小细胞肺癌(non small cell lung cancer,NSCLC)中CXC类趋化因子受体4(chemokine CXC motif receptor 4,CXCR4)、CC类趋化因子体7(chemokine CC motif receptor 7,CCR7)表达的差异性及其表达在局部淋巴结转移中的作用.方法 未做治疗的41例NSCLC肿瘤原发灶,以及25例移淋巴结和20例正常肺组织接SABC免疫组化法观察CXCR4、CCR7的表达.结果 NSCLC原发灶中肿瘤细胞CXCR4、CCR7阳性表达均明显高于正常肺组细胞(P<0.05);CXCR4阳性表达率高于CCR7(分别为92.68%、68.29%;P<0.05).原发灶中CCR7与TNM分期、淋巴结转移状况相关(P<0.05).淋巴结移灶中CXCR4、CCR7表达阳性率差异无统计学意义(96%、84%;P>0.05).结论 NSCLC中肿瘤细胞高表达CXCR4及CCR7可能与肿瘤细胞局部淋巴结靶性转移有关.对NSCLC而言,CCR7的作用可能更为关键.

  5. Similar chemokine receptor profiles in lymphomas with central nervous system involvement - possible biomarkers for patient selection for central nervous system prophylaxis, a retrospective study.

    Science.gov (United States)

    Lemma, Siria A; Pasanen, Anna Kaisa; Haapasaari, Kirsi-Maria; Sippola, Antti; Sormunen, Raija; Soini, Ylermi; Jantunen, Esa; Koivunen, Petri; Salokorpi, Niina; Bloigu, Risto; Turpeenniemi-Hujanen, Taina; Kuittinen, Outi

    2016-05-01

    Central nervous system (CNS) relapse occurs in around 5% of diffuse large B-cell lymphoma (DLBCL) cases. No biomarkers to identify high-risk patients have been discovered. We evaluated the expression of lymphocyte-guiding chemokine receptors in systemic and CNS lymphomas. Immunohistochemical staining for CXCR4, CXCR5, CCR7, CXCL12, and CXCL13 was performed on 89 tissue samples, including cases of primary central nervous system lymphoma (PCNSL), secondary CNS lymphoma (sCNSL), and systemic DLBCL. Also, 10 reactive lymph node samples were included. Immunoelectron microscopy was performed on two PCNSLs, one sCNSL, one systemic DLBCL, and one reactive lymph node samples, and staining was performed for CXCR4, CXCR5, CXCL12, and CXCL13. Chi-square test was used to determine correlations between clinical parameters, diagnostic groups, and chemokine receptor expression. Strong nuclear CXCR4 positivity correlated with systemic DLBCL, whereas strong cytoplasmic CXCR5 positivity correlated with CNS involvement (P = 0.003 and P = 0.039). Immunoelectron microscopy revealed a nuclear CXCR4 staining in reactive lymph node, compared with cytoplasmic and membranous localization seen in CNS lymphomas. We found that CNS lymphoma presented a chemokine receptor profile different from systemic disease. Our findings give new information on the CNS tropism of DLBCL and, if confirmed, may contribute to more effective targeting of CNS prophylaxis among patients with DLBCL.

  6. CXCR4 and CXCL12 (SDF-1) in prostate cancer: inhibitory effects of human single chain Fv antibodies.

    Science.gov (United States)

    Vaday, Gayle G; Hua, Shao-Bing; Peehl, Donna M; Pauling, Michelle H; Lin, Yu-Huei; Zhu, Li; Lawrence, Diana M; Foda, Hussein D; Zucker, Stanley

    2004-08-15

    Metastasis is a major cause of morbidity in prostate cancer (PCa). Several studies have shown that the chemokine receptor CXCR4 and its ligand, CXCL12 (stromal cell-derived factor-1), regulate tumor cell metastasis to specific organs. Recently, it was demonstrated that CXCL12 enhances PCa cell adhesion, migration, and invasion, implicating CXCR4 in PCa metastasis. In this study, we examined the inhibitory effects of anti-CXCR4 antibodies on CXCL12-mediated PCa cell activities. We developed fully human single chain Fv antibodies (scFv), Ab124 and Ab125, against CXCR4 using the yeast two-hybrid system. We performed immunofluorescent staining, flow cytometry, and ELISA-binding assays to measure scFv binding to PCa cells. We also examined the effects of scFv on CXCL12-mediated calcium mobilization, cell migration, and invasion. Our results confirmed that PCa cell lines express cell-surface CXCR4. Real-time quantitative reverse transcription-PCR and immunohistochemical staining also verified that CXCR4 is expressed in primary cultures of prostate epithelial cells from adenocarcinomas and in human prostate tissues. Ab124 and Ab125 demonstrated specific binding to PCa cell lines by flow cytometry and in binding assays. Preincubation with scFv resulted in significant reduction of CXCL12-induced calcium mobilization in PC-3 and LNCaP cells. Ab124 and Ab125 also inhibited PCa cell migration toward CXCL12, as well as invasion through extracellular matrix gels. Ab124 and Ab125 inhibit CXCL12-mediated cellular activities by binding the receptor CXCR4. Recombinant scFv are an efficient mode of targeting tumor antigens. Considering the high incidence of PCa, the development of fully human scFv may be a useful therapeutic approach in the prevention and treatment of PCa metastasis.

  7. CXCR4 antagonist 4F-benzoyl-TN14003 inhibits leukemia and multiple myeloma tumor growth.

    Science.gov (United States)

    Beider, Katia; Begin, Michal; Abraham, Michal; Wald, Hanna; Weiss, Ido D; Wald, Ori; Pikarsky, Eli; Zeira, Evelyne; Eizenberg, Orly; Galun, Eithan; Hardan, Izhar; Engelhard, Dan; Nagler, Arnon; Peled, Amnon

    2011-03-01

    The chemokine receptor CXCR4 and its ligand CXCL12 are involved in the progression and dissemination of a diverse number of solid and hematological malignancies. Binding CXCL12 to CXCR4 activates a variety of intracellular signal transduction pathways that regulate cell chemotaxis, adhesion, survival, proliferation, and apoptosis. Here, we demonstrate that the CXCR4 antagonist, 4F-benzoyl-TN14003 (BKT140), but not AMD3100, exhibits a CXCR4-dependent preferential cytotoxicity toward malignant cells of hematopoietic origin. BKT140 significantly and preferentially stimulated multiple myeloma apoptotic cell death. BKT140 treatment induced morphological changes, phosphatidylserine externalization, decreased mitochondrial membrane potential, caspase-3 activation, sub-G1 arrest, and DNA double-stranded breaks. In vivo, subcutaneous injections of BKT140 significantly reduced, in a dose-dependent manner, the growth of human acute myeloid leukemia and multiple myeloma xenografts. Tumors from animals treated with BKT140 were smaller in size and weights, had larger necrotic areas and high apoptotic scores. Taken together, these results suggest a potential therapeutic use for BKT140 in multiple myeloma and leukemia patients. Copyright © 2011 ISEH - Society for Hematology and Stem Cells. Published by Elsevier Inc. All rights reserved.

  8. Inhibition of signaling between human CXCR4 and zebrafish ligands by the small molecule IT1t impairs the formation of triple-negative breast cancer early metastases in a zebrafish xenograft model

    Directory of Open Access Journals (Sweden)

    Claudia Tulotta

    2016-02-01

    Full Text Available Triple-negative breast cancer (TNBC is a highly aggressive and recurrent type of breast carcinoma that is associated with poor patient prognosis. Because of the limited efficacy of current treatments, new therapeutic strategies need to be developed. The CXCR4-CXCL12 chemokine signaling axis guides cell migration in physiological and pathological processes, including breast cancer metastasis. Although targeted therapies to inhibit the CXCR4-CXCL12 axis are under clinical experimentation, still no effective therapeutic approaches have been established to block CXCR4 in TNBC. To unravel the role of the CXCR4-CXCL12 axis in the formation of TNBC early metastases, we used the zebrafish xenograft model. Importantly, we demonstrate that cross-communication between the zebrafish and human ligands and receptors takes place and human tumor cells expressing CXCR4 initiate early metastatic events by sensing zebrafish cognate ligands at the metastatic site. Taking advantage of the conserved intercommunication between human tumor cells and the zebrafish host, we blocked TNBC early metastatic events by chemical and genetic inhibition of CXCR4 signaling. We used IT1t, a potent CXCR4 antagonist, and show for the first time its promising anti-tumor effects. In conclusion, we confirm the validity of the zebrafish as a xenotransplantation model and propose a pharmacological approach to target CXCR4 in TNBC.

  9. Targeting CXCR4 in HIV Cell-Entry Inhibition

    DEFF Research Database (Denmark)

    Steen, Anne; Schwartz, T W; Rosenkilde, M M

    2010-01-01

    CXCR4 and CCR5 constitute the two major coreceptors for HIV-1 entry into host cells. In the course of an HIV-infection, a coreceptor switch takes place in approximately half of the patients - from R5 HIV-1 (CCR5 utilizing) strains to X4 HIV-1 (CXCR4 utilizing) strains. Treatment of HIV......-infected individuals with CXCR4 antagonists delays the onset of AIDS by preventing the CCR5 to CXCR4 coreceptor switch. In addition to the endogenous CXCR4 and CCR5 ligands, other chemokines, for example the human herpesvirus 8 encoded CC-chemokine, vCCL2, and modifications hereof, have proven efficient HIV-1 cell...... no oral bioavailability. The hunt for orally active small-molecule CXCR4 antagonists led to the development of monocyclam-based compounds, and recently to the non-cyclam antagonist AMD070, which is orally active and currently in Phase II clinical trial as anti-HIV treatment. Current review provides...

  10. Drug-resistant CXCR4-positive cells have the molecular characteristics of EMT in NSCLC.

    Science.gov (United States)

    Yin, Hanlu; Wang, Yi; Chen, Wenping; Zhong, Shanliang; Liu, Zhian; Zhao, Jianhua

    2016-12-05

    High expression of Chemokine receptor 4 (CXCR4) is important in tumor invasion, metastasis, drug-resistance and maintenance of stemness in non-small cell lung cancer (NSCLC). We therefore studied the molecular characteristics of drug-resistant CXCR4-positive cells on epithelial-mesenchymal transition (EMT) for the future identification of the tumor cells with the properties of both EMT and stemness. EMT RT(2) Profier PCR Array was performed to determine the expression levels of mRNA genes in A549 with TGF-β1 induced EMT (A549/TGF-β1) and gefitinib-resistant CXCR4-positive cells (A549/GR). TCGA database on the cBio Cancer Genomics Portal website and Gene Network Central (GNC) Pro Tutorial were used to analyze their clinical relevance and pathway interactions. CXCR4 was up-regulated both in TGF-β induced EMT cells and in gefitinib-resistant cells. In 84 mRNA genes related to EMT, 17 mRNA genes were up-regulated in CXCR4-positive population of A549/GR when compared to those in CXCR4 negative fraction, while 66 mRNA genes were up-regulated during TGF-β induced EMT. ITGA5, BMP7, MMP3, VIM, RGS2, ZEB2, TCF3, SNAI2, VCAN, PLEK2, WNT5A, COL3A1, SPARC and FOXC2 were doubly up-regulated during the two biological processes. Kaplan-Meier analysis indicated that the doubly up-regulated ITGA5, RGS2, SNAI2 and PLEK2 mRNA genes were related to poor overall survival in lung adenocarcinoma patients (P=9.291e-6, 0.0090, 3.81e-7 and 0.0013, respectively). In GNC analysis, SNAI2 mRNA gene but not ITGA5, RGS2 and PLEK2 was dependent on the signaling pathway of CXCR4. The molecular characteristics of drug-resistant CXCR4-positive cells have a crosstalk with EMT, which has the potential to find the marker with prognostic value on multiple signaling pathways in NSCLC. Copyright © 2016 Elsevier B.V. All rights reserved.

  11. Chemokine receptor-specific antibodies in cancer immunotherapy: achievements and challenges.

    Science.gov (United States)

    Vela, Maria; Aris, Mariana; Llorente, Mercedes; Garcia-Sanz, Jose A; Kremer, Leonor

    2015-01-01

    The 1990s brought a burst of information regarding the structure, expression pattern, and role in leukocyte migration and adhesion of chemokines and their receptors. At that time, the FDA approved the first therapeutic antibodies for cancer treatment. A few years later, it was reported that the chemokine receptors CXCR4 and CCR7 were involved on directing metastases to liver, lung, bone marrow, or lymph nodes, and the over-expression of CCR4, CCR6, and CCR9 by certain tumors. The possibility of inhibiting the interaction of chemokine receptors present on the surface of tumor cells with their ligands emerged as a new therapeutic approach. Therefore, many research groups and companies began to develop small molecule antagonists and specific antibodies, aiming to neutralize signaling from these receptors. Despite great expectations, so far, only one anti-chemokine receptor antibody has been approved for its clinical use, mogamulizumab, an anti-CCR4 antibody, granted in Japan to treat refractory adult T-cell leukemia and lymphoma. Here, we review the main achievements obtained with anti-chemokine receptor antibodies for cancer immunotherapy, including discovery and clinical studies, proposed mechanisms of action, and therapeutic applications.

  12. Expressions and significance of VEGF-C and CXCR4 in breast infiltrating ductal carcinoma%VEGF-C、CXCR4在乳腺浸润性导管癌组织中的表达及意义

    Institute of Scientific and Technical Information of China (English)

    杜宏道; 盛薇; 高希涛; 张倩

    2012-01-01

    Objective To investigate the expressions of vascular endothelial growth factor-C (VEGF-C) and chemokines receptor-4 (CXCR4) in breast infiltrating carcinoma and breast fibroadenoma tissues as well as the relationship of lymphatic metastasis and prognosis with breast carcinoma. Methods The expressions of VEGF-C and CXCR4 were detected by immunohistochemical method in 72 cases of breast infiltrating carcinoma and 15 cases of breast fibroadenoma tissues. Results The positive rate of VEGF-C and CXCR4 in breast carcinoma was 76.4% and 58. 3%, respectively. The level of VEGF-C and CXCR4 expressions was significantly higher in breast infiltrating carcinoma than in breast fibroadenoma tissues (P0.05). Conclusion VEGF-C and CXCR4 may play a crucial role in lymphatic vessel invasion and lymph node metastasis in breast cancer.%目的 分析血管内皮生长因子-C(VEGF-C)、趋化因子受体-4(CXCR4)在乳腺浸润性导管癌组织及乳腺纤维腺瘤组织中的表达,探讨其与淋巴管生成、乳腺癌的淋巴转移的关系.方法 应用免疫组织化学方法检测72例乳腺癌组织、15例乳腺纤维腺瘤中VEGF-C、CXCR4的表达.结果 72例乳腺癌组织中VEGF-C、CXCR4的表达率分别为76.4%、58.3%,显著高于乳腺纤维腺瘤组织(20%、13.3%),差异有统计学意义(P<0.01).VEGF-C、CXCR4的表达与患者的年龄、肿瘤大小、雌孕激素受体(ER、PR)的表达无关(P>0.05),而与组织学分级、临床分期、淋巴管的浸润及淋巴结转移有关(P<0.01).结论 VEGF-C、CXCR4在介导乳腺癌细胞淋巴管浸润及淋巴结转移中可能起重要协同作用.

  13. Interaction of chemokines with their receptors--from initial chemokine binding to receptor activating steps

    DEFF Research Database (Denmark)

    Thiele, Stefanie; Rosenkilde, Mette Marie

    2014-01-01

    interactions possibly occur, resulting in a multi-step process, as recently proposed for other 7TM receptors. Overall, the N-terminus of chemokine receptors is pivotal for binding of all chemokines. During receptor activation, differences between the two major chemokine subgroups occur, as CC-chemokines mainly......The human chemokine system comprises 19 seven-transmembrane helix (7TM) receptors and 45 endogenous chemokines that often interact with each other in a promiscuous manner. Due to the chemokine system's primary function in leukocyte migration, it has a central role in immune homeostasis...... and surveillance. Chemokines are a group of 8-12 kDa large peptides with a secondary structure consisting of a flexible N-terminus and a core-domain usually stabilized by two conserved disulfide bridges. They mainly interact with the extracellular domains of their cognate 7TM receptors. Affinityand activity...

  14. Persistent expression of chemokine and chemokine receptor RNAs at primary and latent sites of herpes simplex virus 1 infection

    Directory of Open Access Journals (Sweden)

    Burwell Timothy J

    2004-09-01

    Full Text Available Abstract Inflammatory cytokines and infiltrating T cells are readily detected in herpes simplex virus (HSV infected mouse cornea and trigeminal ganglia (TG during the acute phase of infection, and certain cytokines continue to be expressed at lower levels in infected TG during the subsequent latent phase. Recent results have shown that HSV infection activates Toll-like receptor signaling. Thus, we hypothesized that chemokines may be broadly expressed at both primary sites and latent sites of HSV infection for prolonged periods of time. Real-time reverse transcriptase-polymrease chain reaction (RT-PCR to quantify expression levels of transcripts encoding chemokines and their receptors in cornea and TG following corneal infection. RNAs encoding the inflammatory-type chemokine receptors CCR1, CCR2, CCR5, and CXCR3, which are highly expressed on activated T cells, macrophages and most immature dendritic cells (DC, and the more broadly expressed CCR7, were highly expressed and strongly induced in infected cornea and TG at 3 and 10 days postinfection (dpi. Elevated levels of these RNAs persisted in both cornea and TG during the latent phase at 30 dpi. RNAs for the broadly expressed CXCR4 receptor was induced at 30 dpi but less so at 3 and 10 dpi in both cornea and TG. Transcripts for CCR3 and CCR6, receptors that are not highly expressed on activated T cells or macrophages, also appeared to be induced during acute and latent phases; however, their very low expression levels were near the limit of our detection. RNAs encoding the CCR1 and CCR5 chemokine ligands MIP-1α, MIP-1β and RANTES, and the CCR2 ligand MCP-1 were also strongly induced and persisted in cornea and TG during the latent phase. These and other recent results argue that HSV antigens or DNA can stimulate expression of chemokines, perhaps through activation of Toll-like receptors, for long periods of time at both primary and latent sites of HSV infection. These chemokines recruit

  15. Effects of SDF-1/CXCR4 on Acute Lung Injury Induced by Cardiopulmonary Bypass.

    Science.gov (United States)

    Shi, Hai; Lu, Rujian; Wang, Shuo; Chen, Honglin; Wang, Fei; Liu, Kun

    2017-03-11

    Acute lung injury (ALI) is one of the most important complications after cardiopulmonary bypass (CPB) and the complex pathophysiology remains to be resolved incomplete. SDF-1/CXCR4 chemokine axis can chemotactically accumulate inflammatory cell to local tissue and regulate the release of inflammatory factors, and SDF-1 has a strong chemotaxis effect on neutrophils with CXCR4. Since CPB animal model was difficult to establish, there was still no report about the effect of SDF-1/CXCR4 on neutrophil chemotaxis in ALI after CPB. Here, a stable CPB rat model was constructed to clarify the role of SDF-1/CXCR4 axis in the CPB-induced ALI. Real-time quantitative PCR (RT-qPCR), Western blot analysis, and enzyme-linked immunosorbent assay (ELISA) were used to detect the changes of SDF-1 and CXCR4 in lung tissues, blood, bronchoalveolar lavage (BALF), and/or isolated neutrophils. SDF-1/CXCR4 was increased after CPB, both of that were increased in blood; CXCR4 was increased in neutrophils; SDF-1/CXCR4 was also increased in BALF of CPB model. Results indicated that SDF-1/CXCR4 axis played a key role in the process of early ALI after CPB, also showed that lung injury was significantly reduce after blocking SDF-1/CXCR4 axis, suggest that CXCR4 might be a new target for ALI treatment.

  16. Chemokines and chemokine receptors in stem cell circulation.

    Science.gov (United States)

    Beider, Katia; Abraham, Michal; Peled, Amnon

    2008-05-01

    Stem cells are rare, pluripotent, self-renewing cells that give rise to all mature cells during development and adult life. Due to their proliferative capabilities and their ability to home and contribute to the regeneration of damage tissue, stem cells can be transformed into established tumors. Stem cells can function as a double-edged sword--they have the ability to circulate and migrate throughout the developing and mature adult organism, which is essential for their normal function; however, transformed stem cells are also endowed with the machinery to metastasize into various organs. Chemokine and chemokine receptors play a critical role in directing the trafficking of these cells. It is therefore evident that understanding the role of chemokines and their receptors in stem cell circulation is critical for the successful use of these cells in therapy for a wide variety of pathological conditions.

  17. Impact of a CXCL12/CXCR4 Antagonist in Bleomycin (BLM) Induced Pulmonary Fibrosis and Carbon Tetrachloride (CCl4) Induced Hepatic Fibrosis in Mice

    Science.gov (United States)

    Chow, Leola N.; Schreiner, Petra; Ng, Betina Y. Y.; Lo, Bernard; Hughes, Michael R.; Scott, R. Wilder; Gusti, Vionarica; Lecour, Samantha; Simonson, Eric; Manisali, Irina; Barta, Ingrid; McNagny, Kelly M.; Crawford, Jason; Webb, Murray; Underhill, T. Michael

    2016-01-01

    Modulation of chemokine CXCL12 and its receptor CXCR4 has been implicated in attenuation of bleomycin (BLM)-induced pulmonary fibrosis and carbon tetrachloride (CCl4)-induced hepatic injury. In pulmonary fibrosis, published reports suggest that collagen production in the injured lung is derived from fibrocytes recruited from the circulation in response to release of pulmonary CXCL12. Conversely, in hepatic fibrosis, resident hepatic stellate cells (HSC), the key cell type in progression of fibrosis, upregulate CXCR4 expression in response to activation. Further, CXCL12 induces HSC proliferation and subsequent production of collagen I. In the current study, we evaluated AMD070, an orally bioavailable inhibitor of CXCL12/CXCR4 in alleviating BLM-induced pulmonary and CCl4-induced hepatic fibrosis in mice. Similar to other CXCR4 antagonists, treatment with AMD070 significantly increased leukocyte mobilization. However, in these two models of fibrosis, AMD070 had a negligible impact on extracellular matrix deposition. Interestingly, our results indicated that CXCL12/CXCR4 signaling has a role in improving mortality associated with BLM induced pulmonary injury, likely through dampening an early inflammatory response and/or vascular leakage. Together, these findings indicate that the CXCL12-CXCR4 signaling axis is not an effective target for reducing fibrosis. PMID:26998906

  18. Stage-specific roles for CXCR4 signaling in murine hematopoietic stem/progenitor cells in the process of bone marrow repopulation.

    Science.gov (United States)

    Lai, Chen-Yi; Yamazaki, Satoshi; Okabe, Motohito; Suzuki, Sachie; Maeyama, Yoshihiro; Iimura, Yasuaki; Onodera, Masafumi; Kakuta, Shigeru; Iwakura, Yoichiro; Nojima, Masanori; Otsu, Makoto; Nakauchi, Hiromitsu

    2014-07-01

    Hematopoietic cell transplantation has proven beneficial for various intractable diseases, but it remains unclear how hematopoietic stem/progenitor cells (HSPCs) home to the bone marrow (BM) microenvironment, initiate hematopoietic reconstitution, and maintain life-long hematopoiesis. The use of newly elucidated molecular determinants for overall HSPC engraftment should benefit patients. Here, we report that modification of C-X-C chemokine receptor type 4 (Cxcr4) signaling in murine HSPCs does not significantly affect initial homing/lodging events, but leads to alteration in subsequent BM repopulation kinetics, with observations confirmed by both gain- and loss-of-function approaches. By using C-terminal truncated Cxcr4 as a gain-of-function effector, we demonstrated that signal augmentation likely led to favorable in vivo repopulation of primitive cell populations in BM. These improved features were correlated with enhanced seeding efficiencies in stromal cell cocultures and altered ligand-mediated phosphorylation kinetics of extracellular signal-regulated kinases observed in Cxcr4 signal-augmented HSPCs in vitro. Unexpectedly, however, sustained signal enhancement even with wild-type Cxcr4 overexpression resulted in impaired peripheral blood (PB) reconstitution, most likely by preventing release of donor hematopoietic cells from the marrow environment. We thus conclude that timely regulation of Cxcr4/CXCR4 signaling is key in providing donor HSPCs with enhanced repopulation potential following transplantation, whilst preserving the ability to release HSPC progeny into PB for improved transplantation outcomes.

  19. Chemokines

    Directory of Open Access Journals (Sweden)

    Richard Horuk

    2007-01-01

    Full Text Available Chemokines are a family of polypeptides that direct the migration of leukocytestoward a site of infection. They play a major role in autoimmune disease and chemokine receptors have recently been found to mediate HIV-1 fusion. In this short review we examine the role of chemokines in host defence and in the pathophysiology of autoimmune diseases. We conclude by discussing various therapeutic approaches that target chemokine receptors and that could be beneficial in disease.

  20. Retrograde migration of pectoral girdle muscle precursors depends on CXCR4/SDF-1 signaling.

    Science.gov (United States)

    Masyuk, Maryna; Abduelmula, Aisha; Morosan-Puopolo, Gabriela; Ödemis, Veysel; Rehimi, Rizwan; Khalida, Nargis; Yusuf, Faisal; Engele, Jürgen; Tamamura, Hirokazu; Theiss, Carsten; Brand-Saberi, Beate

    2014-11-01

    In vertebrates, muscles of the pectoral girdle connect the forelimbs with the thorax. During development, the myogenic precursor cells migrate from the somites into the limb buds. Whereas most of the myogenic precursors remain in the limb bud to form the forelimb muscles, several cells migrate back toward the trunk to give rise to the superficial pectoral girdle muscles, such as the large pectoral muscle, the latissimus dorsi and the deltoid. Recently, this developing mode has been referred to as the "In-Out" mechanism. The present study focuses on the mechanisms of the "In-Out" migration during formation of the pectoral girdle muscles. Combining in ovo electroporation, tissue slice-cultures and confocal laser scanning microscopy, we visualize live in detail the retrograde migration of myogenic precursors from the forelimb bud into the trunk region by live imaging. Furthermore, we present for the first time evidence for the involvement of the chemokine receptor CXCR4 and its ligand SDF-1 during these processes. After microsurgical implantations of CXCR4 inhibitor beads in the proximal forelimb region of chicken embryos, we demonstrate with the aid of in situ hybridization and live-cell imaging that CXCR4/SDF-1 signaling is crucial for the retrograde migration of pectoral girdle muscle precursors. Moreover, we analyzed the MyoD expression in CXCR4-mutant mouse embryos and observed a considerable decrease in pectoral girdle musculature. We thus demonstrate the importance of the CXCR4/SDF-1 axis for the pectoral girdle muscle formation in avians and mammals.

  1. Chemokines in the skin

    Directory of Open Access Journals (Sweden)

    Prasad D

    1998-01-01

    Full Text Available In last few years, focus has shifted from cytokines which have pleiotropic biologic properties to chemokines with target cell selective activity. The separation has led frequently espoused proposition that chemokines are involved in the pathogenesis of disease having specific infiltrates and point to possible role in Chronic skin diseases. Depending upon the structure these chemokines are divided into three subfamilies, two major subfamilies: CXC and CC, and one putative subfamily C with only one member known as lymphotactin. A recent insight into chemokine physiology comes from demonstration of interaction between chemokines and their cloned receptors. These chemokine receptors are members of the transmembrane spanning (7-TMS, G-protein- coupled receptor family. So far CXC chemokine receptors and seven CC receptors have been cloned. Recently, the importance of selective chemoattractant activity of chemokines has been overshadowed by chemokine receptors emerging as new targets for anti-HIV therapy as the connection between chemokines and HIV-I had been established. Among the CXC chemokine receptors, CXCR4, and among the CC chemokines receptors, CCRI, CCR2b, CCR3, and CCR5 have been implicated as HIV-1 coreceptors.

  2. Macrophage Densities Correlated with CXC Chemokine Receptor 4 Expression and Related with Poor Survival in Anaplastic Thyroid Cancer

    Directory of Open Access Journals (Sweden)

    Dae In Kim

    2016-09-01

    Full Text Available BackgroundTumor associated macrophages (TAMs and CXC chemokine receptor 4 (CXCR4 have emerged as potential biomarkers in various human cancers. The aims of this study were to investigate the clinical characteristics of anaplastic thyroid cancer (ATC patients according to the TAM numbers in the tumor tissue, and to evaluate the associations between CXCR4 expressions and macrophage densities in ATC tumor microenvironment.MethodsTotal 14 ATC samples from thyroid tissue microarray were used. Immunohistochemical staining was performed using anti-CD163 and anti-CXCR4 antibodies. According to the immunoreactivity of CD163, all subjects were divided into two groups: low-CD163 (n=8 and high-CD163 (n=6 groups.ResultsThe mean diagnostic age was 65±7 years and the median tumor size was 4.3 cm, ranging 2.5 to 15 cm. Clinicopathological characteristics were not significantly different between low-CD163 and high-CD163 groups, while age of diagnosis was younger in high-CD163 group than that of low-CD163 group with marginal significance (56.9±5.5 years vs. 67.5±6.8 years, P=0.09. However, overall survival was significantly reduced in high-CD163 group (5.5 months [range, 1 to 10] compared with low-CD163 groups (8.8 months [range, 6 to 121; log-rank test, P=0.0443. Moreover, high-CD163 group showed strong CXCR4 expressions in both cancer and stromal compartments, while low-CD163 group showed relatively weak, stromal-dominant CXCR4 expressions. Additionally, CD163 and CXCR4 expressions showed a strong positive correlation (γ2=0.432, P=0.013.ConclusionIncreased number of TAMs showed poor overall survival in ATC, suggesting TAMs are potentially a prognostic biomarker for ATC. CXCR4 expression was significantly correlated with CD163-positive TAM densities, which suggest the possible role of CXCR4 in TAM recruitments.

  3. The SDF-1α/CXCR4 axis is required for proliferation and maturation of human fetal pancreatic endocrine progenitor cells.

    Directory of Open Access Journals (Sweden)

    Ayse G Kayali

    Full Text Available The chemokine receptor CXCR4 and ligand SDF-1α are expressed in fetal and adult mouse islets. Neutralization of CXCR4 has previously been shown to diminish ductal cell proliferation and increase apoptosis in the IFNγ transgenic mouse model in which the adult mouse pancreas displays islet regeneration. Here, we demonstrate that CXCR4 and SDF-1α are expressed in the human fetal pancreas and that during early gestation, CXCR4 colocalizes with neurogenin 3 (ngn3, a key transcription factor for endocrine specification in the pancreas. Treatment of islet like clusters (ICCs derived from human fetal pancreas with SDF-1α resulted in increased proliferation of epithelial cells in ICCs without a concomitant increase in total insulin expression. Exposure of ICCs in vitro to AMD3100, a pharmacological inhibitor of CXCR4, did not alter expression of endocrine hormones insulin and glucagon, or the pancreatic endocrine transcription factors PDX1, Nkx6.1, Ngn3 and PAX4. However, a strong inhibition of β cell genesis was observed when in vitro AMD3100 treatment of ICCs was followed by two weeks of in vivo treatment with AMD3100 after ICC transplantation into mice. Analysis of the grafts for human C-peptide found that inhibition of CXCR4 activity profoundly inhibits islet development. Subsequently, a model pancreatic epithelial cell system (CFPAC-1 was employed to study the signals that regulate proliferation and apoptosis by the SDF-1α/CXCR4 axis. From a selected panel of inhibitors tested, both the PI 3-kinase and MAPK pathways were identified as critical regulators of CFPAC-1 proliferation. SDF-1α stimulated Akt phosphorylation, but failed to increase phosphorylation of Erk above the high basal levels observed. Taken together, these results indicate that SDF-1α/CXCR4 axis plays a critical regulatory role in the genesis of human islets.

  4. Modulation of chemokine and chemokine receptor expression following infection of porcine macrophages with African swine fever virus.

    Science.gov (United States)

    Fishbourne, Emma; Abrams, Charles C; Takamatsu, Haru-H; Dixon, Linda K

    2013-03-23

    African swine fever virus (ASFV) is the only member of the Asfarviridae, a large DNA virus family which replicates predominantly in the cytoplasm. Most isolates cause a fatal haemorrhagic disease in domestic pigs, although some low virulence isolates cause little or no mortality. The modulation of chemokine responses following infection of porcine macrophages with low and high virulence isolates was studied to indicate how this may be involved in the induction of pathogenesis and of effective immune responses. Infection with both low and high virulence isolates resulted in down-regulation of mRNA levels for chemokines CCL2, CCL3L, CXCL2 and chemokine receptors CCR1, CCR5, CXCR3, CXCR4 and up-regulation in expression of mRNAs for CCL4, CXCL10 and chemokine receptor CCR7. Levels of CCL4, CXCL8, CXCL10 mRNAs were higher in macrophages infected with low virulence isolate OURT88/3 compared to high virulence isolate Benin 97/1. Levels of CXCL8 and CCL2 protein were significantly reduced in supernatants from macrophages infected with Benin 97/1 isolate compared to OURT88/3 and mock-infected macrophages. There was also a decreased chemotactic response of donor cells exposed to supernatants from Benin 97/1 infected macrophages compared to those from OURT88/3 and mock-infected macrophages. The data show that infection of macrophages with the low virulence strain OURT88/3 induces higher expression of key inflammatory chemokines compared to infection with high virulence strain Benin 97/1. This may be important for the induction of effective protective immunity that has been observed in pigs immunised with the OURT88/3 isolate.

  5. Granulocyte colony-stimulating factor inhibits CXCR4/SDF-1α signaling and overcomes stromal-mediated drug resistance in the HL-60 cell line.

    Science.gov (United States)

    Sheng, Xianfu; Zhong, Hua; Wan, Haixia; Zhong, Jihua; Chen, Fangyuan

    2016-07-01

    Combining cytarabine, aclarubicin and granulocyte colony-stimulating factor (G-CSF) has demonstrated marked efficacy in the treatment of elderly and relapsed/refractory patients with acute myeloid leukemia (AML); however, the role of G-CSF remains poorly understood. The present study aimed to investigate the ability of G-CSF to overcome stromal-mediated drug resistance and the underlying molecular mechanism. Two types of co-culture models were established in the HS-5 human bone marrow/stromal and HL-60 human promyelocytic leukemia cell lines, in order to imitate the interactions between stromal and leukemia cells in vitro, which is mediated by the stromal cell-derived factor (SDF)-1α signaling axis. In the present study, HL-60 cells were attracted and adhered to HS-5 cells using migration assay and flow cytometry, respectively; however, these interactions were inhibited by treatment with G-CSF and/or the C-X-C chemokine receptor type 4 (CXCR4) antagonist, AMD3100. Co-culture with HS-5 cells, including direct and indirect contact, protected HL-60 cells against spontaneous apoptosis or drug-induced apoptosis; however, these protective effects were disrupted by treatment with G-CSF and/or AMD3100. Notably, G-CSF and/or AMD3100 did not alter cell viability or apoptosis when HL-60 cells were cultured with medium alone. In addition, G-CSF significantly reduced the expression levels of surface CXCR4 protein, total CXCR4 protein and CXCR4 mRNA, and significantly upregulated the expression of microRNA (miR)-146a. Conversely, AMD3100 significantly reduced surface CXCR4 expression levels, but not the total CXCR4, CXCR4 mRNA or miR-146a expression levels. The results of the present study suggested that interfering with the CXCR4/SDF-1α signaling axis via G-CSF inhibited the migration and adhesion of HL-60 cells to HS-5 cells and eliminated HS5 cell-mediated protective effects. Furthermore, G-CSF administration reduced CXCR4 expression levels by upregulating the expression of

  6. Genetic Polymorphism and Expression of CXCR4 in Breast Cancer

    Directory of Open Access Journals (Sweden)

    Marina Okuyama Kishima

    2015-01-01

    Full Text Available CXCR4 genetic polymorphisms, as well as their expression level, have been associated with cancer development and prognosis. The present study aimed to investigate the influence of CXCR4 rs2228014 polymorphism on its mRNA and protein expression in breast cancer samples. It was observed that patients presented higher CXCR4 mRNA relative expression (5.7-fold than normal mammary gland, but this expression was not correlated with patients clinicopathological features (nuclear grade, nodal status, ER status, PR status, p53 staining, Ki67 index, and HER-2 status. Moreover, CXCR4 mRNA relative expression also did not differ regarding the presence or absence of T allele (p=0.301. In the immunohistochemical assay, no difference was observed for CXCR4 cytoplasmic protein staining in relation to different genotypes (p=0.757; however, high cytoplasmic CXCR4 staining was verified in invasive breast carcinoma (p<0.01. All in all, the results from present study indicated that rs2228014 genetic variant does not alter CXCR4 mRNA or protein expression. However, this receptor was more expressed in tumor compared to normal tissue, in both RNA and protein levels, suggesting its promising applicability in the general context of mammary carcinogenesis.

  7. Genetic Polymorphism and Expression of CXCR4 in Breast Cancer

    Science.gov (United States)

    Okuyama Kishima, Marina; Brajão de Oliveira, Karen; Ariza, Carolina Batista; de Oliveira, Carlos Eduardo Coral; Losi Guembarovski, Roberta; Banin Hirata, Bruna Karina; de Almeida, Felipe Campos; Vitiello, Glauco Akelinghton Freire; Trugilo, Kleber Paiva; Guembarovski, Alda Fiorina Maria Losi; Jorge Sobrinho, Walter; Campos, Clodoaldo Zago; Watanabe, Maria Angelica Ehara

    2015-01-01

    CXCR4 genetic polymorphisms, as well as their expression level, have been associated with cancer development and prognosis. The present study aimed to investigate the influence of CXCR4 rs2228014 polymorphism on its mRNA and protein expression in breast cancer samples. It was observed that patients presented higher CXCR4 mRNA relative expression (5.7-fold) than normal mammary gland, but this expression was not correlated with patients clinicopathological features (nuclear grade, nodal status, ER status, PR status, p53 staining, Ki67 index, and HER-2 status). Moreover, CXCR4 mRNA relative expression also did not differ regarding the presence or absence of T allele (p = 0.301). In the immunohistochemical assay, no difference was observed for CXCR4 cytoplasmic protein staining in relation to different genotypes (p = 0.757); however, high cytoplasmic CXCR4 staining was verified in invasive breast carcinoma (p < 0.01). All in all, the results from present study indicated that rs2228014 genetic variant does not alter CXCR4 mRNA or protein expression. However, this receptor was more expressed in tumor compared to normal tissue, in both RNA and protein levels, suggesting its promising applicability in the general context of mammary carcinogenesis. PMID:26576337

  8. CXCR4 antagonist AMD3100 attenuates colonic damage in mice with experimental colitis

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    AIM:To investigate the effects of the chemokine stromal cell-derived factor-1(CXCL12) receptor(CXCR4) antagonist AMD3100 on colonic inflammation and epithelial barrier in dextran sulfate sodium(DSS)-induced colitis in mice.METHODS:Experimental colitis was induced by administration of 5% DSS for 7 d,and assays performed on intestinal segments from the ileocecal valve to the anus.Colonic morphology was examined by hematoxylin and eosin staining.Colonic cytokines were determined by enzyme-linked immunosorbent ...

  9. SDF-1α及其受体CXCR4与HIF-1α、VEGF在脑动静脉畸形中的表达%Expressions of stromal-cell derived factor-1α and its receptor CXCR4, hypoxia inducible factor-1α and vascular endothelial growth factor in brain arteriovenous malformation

    Institute of Scientific and Technical Information of China (English)

    王凌雁; 郭少雷; 齐铁伟; 梁丰; 黄正松

    2014-01-01

    Objective To investigate the expressions ofstromal-cell derived factor-1α (SDF-1α)and its receptor CXCR4 in brain arteriovenous malformation (AVM) and to explore the relationships of SDF-1α with hypoxia inducible factor-1α (HIF-1α) and vascular endothelial growth factor (VEGF).Methods Surgical specimens from 48 patients accepted brain AVM resection,collected in our hospital from January 2012 to December 2013,were studied for expressions ofSDF-1α,CXCR4,VEGF and HIF-1α by immunohistochemical staining.The relationships of SDF-1α with VEGF and HIF-1α were analyzed and influences of embolism,hemorrhage and Spetzer-Martin classification in SDF-1α expression were assessed.Results SDF-1α and CXCR4 expressed in 100% and 83.3% AVM specimens,respectively.The positive staining for SDF-1α was observed in the cytoplasm of vascular endothelium within the nidus and smooth muscle cells of vascular wall.CXCR4 expressed in vascular endothelium and perivascular cells located in the space between the abnormal vessels.SDF-1α expression was significantly associated with VEGF and HIF-1α (r=0.537 and 0.437,respectively,P<0.05).SDF-1α showed more intense expression in embolized patients than that in non-embolized patients (P< 0.05),while no significant difference was noted between patients with and without hemorrhage and between patients of different Spetzer-Martin classifications (P>0.05).Conclusion SDF-1α and its receptor CXCR4 highly express in brain AVM; preoperative embolization might induce expression of SDF-1α.%目的 观察脑动静脉畸形(AVM)病灶内间质细胞衍生因子-1α(SDF-1α)及其受体CXCR4的表达情况,以及SDF-1α与低氧诱导因子-1α(HIF-1α)和血管内皮生长因子(VEGF)表达的关系. 方法 选择中山大学附属第一医院神经外科自2012年1月至2013年12月经手术切除并经病理组织学证实的脑AVM标本共48例,应用免疫组化染色方法检测SDF-1α、CXCR4、HIF-1α和VEGF的表达情况,

  10. Mimicking protein-protein interactions through peptide-peptide interactions: HIV-1 gp120 and CXCR4

    Directory of Open Access Journals (Sweden)

    Andrea eGross

    2013-09-01

    Full Text Available We have recently designed a soluble synthetic peptide that functionally mimics the HIV-1 coreceptor CXCR4, which is a chemokine receptor that belongs to the family of seven-transmembrane GPCRs. This CXCR4 mimetic peptide, termed CX4-M1, presents the three extracellular loops (ECLs of the receptor. In binding assays involving recombinant proteins, as well as in cellular infection assays, CX4-M1 was found to selectively recognize gp120 from HIV-1 strains that use CXCR4 for cell entry (X4 tropic HIV-1. Furthermore, anti-HIV-1 antibodies modulate this interaction in a molecular mechanism related to that of their impact on the gp120-CXCR4 interaction. We could now show that the selectivity of CX4-M1 pertains not only to gp120 from X4 tropic HIV-1, but also to synthetic peptides presenting the V3 loops of these gp120 proteins. The V3 loop is thought to be an essential part of the coreceptor binding site of gp120 that contacts the second ECL of the coreceptor. We were able to experimentally confirm this notion in binding assays using substitution analogs of CX4-M1 and the V3 loop peptides, respectively, as well as in cellular infection assays. These results indicate that interactions of the HIV-1 Env with coreceptors can be mimicked by synthetic peptides, which may be useful to explore these interactions at the molecular level in more detail.

  11. Over-expression of CXCR4, a stemness enhancer, in human blastocysts by low level laser irradiation

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    Mohammad Hossein Tahmasbi

    2013-09-01

    Full Text Available The key role of chemokine receptor CXCR4 in the maintenance of stemness property of stem cells has been shown recently. The low level laser irradiation (LLLI is being used currently in a wide variety of clinical cases as a therapeutic tool for wound healing, relieving pain and destroying tumor cells. The aim of this study was to evaluate the effect of LLLI mimicking low level laser therapy (LLLT on the expression level of CXCR4 gene a few hours after irradiation on human blastocysts. After the development of human embryos to the first grade blastocyst stage, they were irradiated with a low power Ga-Al-As laser at a continuous wavelength of 650 nm and a power output of 30 mW. The total RNA of the irradiated blastocysts and control groups were isolated in groups of 1x2 J/cm2, 2x2 J/cm2, 1x4 J/cm2 and 2x4 J/cm2 LLLI. Specific Real-Time PCR primers were designed to amplify all the two CXCR4 isoforms yet identified. RNA amplifications were done for all the groups. We showed for the first time that LLLI makes the human blastocysts to increase the expression level of CXCR4 a few hours after irradiation. Moreover, it was shown that two irradiation doses with one day interval can cause a significant increase in CXCR4 expression level in human blastocysts. This study revealed that LLLI could be a proliferation motivator for embryonic cell divisions through enhanced over-expression of CXCR4 level.

  12. Down-Regulation of CXCL12/CXCR4 Expression Alleviates Ischemia-Reperfusion-Induced Inflammatory Pain via Inhibiting Glial TLR4 Activation in the Spinal Cord

    Science.gov (United States)

    Li, Xiao-Qian; Zhang, Zai-Li; Tan, Wen-Fei; Sun, Xi-Jia; Ma, Hong

    2016-01-01

    Toll-like receptor 4 (TLR4) is important for the pathogenesis of inflammatory reactions and the promotion of pain processing after ischemia/reperfusion (IR) in spinal cord. Recently, C-X-C chemokine ligand 12 (CXCL12) and its receptor, C-X-C chemokine receptor 4 (CXCR4), were demonstrated to be simultaneously critical for inflammatory reactions, thereby facilitating glial activation. However, whether CXCL12/CXCR4 expression can contribute to IR-induced inflammatory pain via spinal TLR4 remained unclear. A rat model was established by 8 min of aortic arch occlusion. The effects of CXCL12/CXCR4 expression and TLR4 activation on inflammatory hyperalgesia were investigated by pretreatments with CXCL12-neutralizing antibody, CXCR4 antagonist (AMD3100) and TLR4 antagonist (TAK-242) for 5 consecutive days before surgery. The results indicated that IR induced significant and sustained inflammatory pain, observed as decreases in paw withdrawal threshold (PWT) and paw withdrawal latency (PWL), throughout the post-injury period. The increased levels of TLR4 and proinflammatory chemokine CXCL12, as well as its receptor, CXCR4, were closely correlated with the PWT and PWL trends. Double immunostaining further suggested that TLR4, which is mainly expressed on astrocytes and microglia, was closely co-localized with CXCL12 and CXCR4 in spinal dorsal horn. As expected, intrathecal pretreatment with the TLR4 antagonist, TAK-242 markedly ameliorated pain by inhibiting astrocytic and microglial activation, as shown by decreases in TLR4 immunoreactivity and the percentage of double-labeled cells. These protective effects were likely due in part to the reduced production of the downstream cytokines IL-1β and TNF-α, as well as for the recruitment of CXCL12 and CXCR4. Additionally, intrathecal pretreatment with CXCL12-neutralizing antibody and AMD3100 resulted in similar analgesic and anti-inflammatory effects as those receiving TAK-242 pretreatment. These results suggest that

  13. NF-κB2 Controls Migratory Activity of Memory T Cells by Regulating Expression of CXCR4 in A Mouse Model of Sjögren's Syndrome.

    Science.gov (United States)

    Kurosawa, Mie; Arakaki, Rieko; Yamada, Akiko; Tsunematsu, Takaaki; Kudo, Yasusei; Sprent, Jonathan; Ishimaru, Naozumi

    2017-08-13

    Dysregulated chemokine signaling contributes to autoimmune diseases by facilitating aberrant T-cell infiltration into target tissues, but the specific chemokines, receptors, and T-cell populations remain largely unidentified. Role of the potent chemokine CXCL12 and its receptor CXCR4 in T-cell autoimmune response was examined using alymphoplasia (aly)/aly mice, a Sjögren's syndrome (SS) model. T-cell phenotypes in the salivary gland of aly/aly mice were evaluated using immunological analysis. In vitro migration assay was used to assess T-cell migratory activity toward several chemokines. Gene expression of chemokine receptors, and transforming growth factor (TGF)β receptors was measured with quantitative reverse transcription-polymerase chain reaction. The CXCR4 antagonist AMD3100 was administered to the aly/aly mice to evaluate its suppressive effect on autoimmune lesions. Effector memory T (TEM) cells derived from aly/aly mice demonstrated higher in vitro migratory activity toward CXCL12 than aly/+ TEM cells. CXCL12 expression was specifically upregulated in the SS target cells of aly/aly mice. TEM cells from RelB(-/-) mice, but not nuclear factor (NF)-κB1(-/-) mice, also showed high migratory activity toward CXCL12, implicating a nonclassical NF-κB2/RelB pathway in the regulation of TEM cell migration. TEM cells from aly/aly mice also overexpressed TGFβ receptors I and II. The CXCR4 antagonist AMD3100 suppressed autoimmune lesions in aly/aly mice by reducing TEM cell infiltration. Our results suggest that the NF-κB2/RelB pathway regulates T-cell migration to autoimmune targets through TGFβ/TGFβR-dependent regulation of CXCL12-CXCR4 signaling. This suggests that these signaling pathways are potential therapeutic targets for treating autoimmune diseases. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  14. Rational Design of CXCR4 Specific Antibodies with Elongated CDRs

    Science.gov (United States)

    2015-01-01

    The bovine antibody (BLV1H12) which has an ultralong heavy chain complementarity determining region 3 (CDRH3) provides a novel scaffold for antibody engineering. By substituting the extended CDRH3 of BLV1H12 with modified CXCR4 binding peptides that adopt a β-hairpin conformation, we generated antibodies specifically targeting the ligand binding pocket of CXCR4 receptor. These engineered antibodies selectively bind to CXCR4 expressing cells with binding affinities in the low nanomolar range. In addition, they inhibit SDF-1-dependent signal transduction and cell migration in a transwell assay. Finally, we also demonstrate that a similar strategy can be applied to other CDRs and show that a CDRH2-peptide fusion binds CXCR4 with a Kd of 0.9 nM. This work illustrates the versatility of scaffold-based antibody engineering and could greatly expand the antibody functional repertoire in the future. PMID:25041362

  15. Chapter 8. Activation mechanisms of chemokine receptors

    DEFF Research Database (Denmark)

    Jensen, Pia C; Rosenkilde, Mette M

    2009-01-01

    Chemokine receptors belong to the large family of 7-transmembrane (7TM) G-protein-coupled receptors. These receptors are targeted and activated by a variety of different ligands, indicating that activation is a result of similar molecular mechanisms but not necessarily similar modes of ligand bin...

  16. [Chemokine CC receptors in the nervous system].

    Science.gov (United States)

    Radzik, Tomasz Łukasz; Głabiński, Andrzej; Żylińska, Ludmiła

    2015-01-01

    Chemoattractant cytokines (chemokines) are traditionally known as the important mediators of inflammatory processes, however, recently, is also given to their other functions in the body. Acting through specific receptors belonging to the G proteins they regulate immune processes in the body. About 20 chemokine receptors have been identified so far, and 10 of them bind chemokines CC, i.e. having in amino-terminal domain 2 adjacent molecules of cysteins. An increasing number of data indicates that chemokines and their receptors play an important role in the nervous system by acting as trophic factors, increasing the neurons survival, neural migration and synaptic transmission. Special role chemokine receptors play primarily in the diseases of the nervous system, because due to damage of the blood-brain barrier and the blood cerebrospinal fluid barrier, infiltration of leukocytes results in development of inflammation. Chemokine CC receptors has been shown to participate in Alzheimer's disease, multiple sclerosis, dementia associated with HIV infection, stroke or some type of cancers.

  17. Effect of SDF-1/Cxcr4 Signaling Antagonist AMD3100 on Bone Mineralization in Distraction Osteogenesis.

    Science.gov (United States)

    Xu, Jia; Chen, Yuanfeng; Liu, Yang; Zhang, Jinfang; Kang, Qinglin; Ho, Kiwai; Chai, Yimin; Li, Gang

    2017-03-16

    Distraction osteogenesis (DO) is a widely applied technique in orthopedics surgery, which involves rapid stem cell migration, homing, and differentiation. Interactions between the chemokine receptor Cxcr4 and its ligand, stromal derived factor-1 (SDF-1), regulate hematopoietic stem cell trafficking to the ischemic area and induce their subsequent differentiation. Here, we examined SDF-1 expression and further investigated the role of SDF-1/Cxcr4 signaling antagonist AMD3100 during bone regeneration in rat DO model. The results showed that expression levels of SDF-1 and osteogenic genes were higher in DO zones than in the fracture zones, and SDF-1 expression level was the highest at the termination of the distraction phase. Radiological, mechanical, and histological analyses demonstrated that the local administration of AMD3100 (400 μM) to DO rats significantly inhibited new bone formation. In the rat bone marrow mesenchymal stem cells culture, comparing to the group treated with osteogenic induction medium, AMD3100 supplement led to a considerable decrease in the expression of alkaline phosphatase and early osteogenic marker genes. However, the amount of calcium deposits in rat MSCs did not differ between the groups. Therefore, our study demonstrated that the DO process induced higher expression of SDF-1, which collated to rapid induction of callus formation. Local application of SDF-1/Cxcr4 signaling antagonist AMD3100 significantly inhibited bone mineralization and osteogenesis in DO, which may represent a potential therapeutic approach to the enhancement of bone consolidation in patients undergoing DO.

  18. Chemokine Receptors in Epithelial Ovarian Cancer

    Directory of Open Access Journals (Sweden)

    Goda G. Muralidhar

    2013-12-01

    Full Text Available Ovarian carcinoma is the deadliest gynecologic malignancy with very poor rate of survival, and it is characterized by the presence of vast incurable peritoneal metastasis. Studies of the role of chemokine receptors, a family of proteins belonging to the group of G protein-coupled receptors, in ovarian carcinoma strongly placed this family of membrane receptors as major regulators of progression of this malignancy. In this review, we will discuss the roles that chemokine-receptor interactions play to support angiogenesis, cell proliferation, migration, adhesion, invasion, metastasis, and immune evasion in progression of ovarian carcinoma. Data regarding the role that the chemokine receptors play in the disease progression accumulated insofar strongly suggest that this family of proteins could be good therapeutic targets against ovarian carcinoma.

  19. Ibrutinib inhibits CD20 upregulation on CLL B cells mediated by the CXCR4/SDF-1 axis.

    Science.gov (United States)

    Pavlasova, Gabriela; Borsky, Marek; Seda, Vaclav; Cerna, Katerina; Osickova, Jitka; Doubek, Michael; Mayer, Jiri; Calogero, Raffaele; Trbusek, Martin; Pospisilova, Sarka; Davids, Matthew S; Kipps, Thomas J; Brown, Jennifer R; Mraz, Marek

    2016-09-22

    Agents targeting B-cell receptor (BCR) signaling-associated kinases such as Bruton tyrosine kinase (BTK) or phosphatidylinositol 3-kinase can induce mobilization of neoplastic B cells from the lymphoid tissues into the blood, which makes them potentially ideal to combine with anti-CD20 monoclonal antibodies (such as rituximab, obinutuzumab, or ofatumumab) for treatment of B-cell lymphomas and chronic lymphocytic leukemia (CLL). Here we show that interactions between leukemia cells and stromal cells (HS-5) upregulate CD20 on CLL cells and that administering ibrutinib downmodulates CD20 (MS4A1) expression in vivo. We observed that CLL cells that have recently exited the lymph node microenvironment and moved into the peripheral blood (CXCR4(dim)CD5(bright) subpopulation) have higher cell surface levels of CD20 than the cells circulating in the bloodstream for a longer time (CXCR4(bright)CD5(dim) cells). We found that CD20 is directly upregulated by CXCR4 ligand stromal cell-derived factor 1 (SDF-1α, CXCL12) produced by stromal cells, and BTK-inhibitor ibrutinib and CXCR4-inhibitor plerixafor block SDF-1α-mediated CD20 upregulation. Ibrutinib also downmodulated Mcl1 levels in CLL cells in vivo and in coculture with stromal cells. Overall, our study provides a first detailed mechanistic explanation of CD20 expression regulation in the context of chemokine signaling and microenvironmental interactions, which may have important implications for microenvironment-targeting therapies.

  20. Combined Wnt/β-Catenin, Met, and CXCL12/CXCR4 Signals Characterize Basal Breast Cancer and Predict Disease Outcome

    Directory of Open Access Journals (Sweden)

    Jane D. Holland

    2013-12-01

    Full Text Available Prognosis for patients with estrogen-receptor (ER-negative basal breast cancer is poor, and chemotherapy is currently the best therapeutic option. We have generated a compound-mutant mouse model combining the activation of β-catenin and HGF (Wnt-Met signaling, which produced rapidly growing basal mammary gland tumors. We identified the chemokine system CXCL12/CXCR4 as a crucial driver of Wnt-Met tumors, given that compound-mutant mice also deficient in the CXCR4 gene were tumor resistant. Wnt-Met activation rapidly expanded a population of cancer-propagating cells, in which the two signaling systems control different functions, self-renewal and differentiation. Molecular therapy targeting Wnt, Met, and CXCR4 in mice significantly delayed tumor development. The expression of a Wnt-Met 322 gene signature was found to be predictive of poor survival of human patients with ER-negative breast cancers. Thus, targeting CXCR4 and its upstream activators, Wnt and Met, might provide an efficient strategy for breast cancer treatment.

  1. Combined Wnt/β-catenin, Met, and CXCL12/CXCR4 signals characterize basal breast cancer and predict disease outcome.

    Science.gov (United States)

    Holland, Jane D; Györffy, Balázs; Vogel, Regina; Eckert, Klaus; Valenti, Giovanni; Fang, Liang; Lohneis, Philipp; Elezkurtaj, Sefer; Ziebold, Ulrike; Birchmeier, Walter

    2013-12-12

    Prognosis for patients with estrogen-receptor (ER)-negative basal breast cancer is poor, and chemotherapy is currently the best therapeutic option. We have generated a compound-mutant mouse model combining the activation of β-catenin and HGF (Wnt-Met signaling), which produced rapidly growing basal mammary gland tumors. We identified the chemokine system CXCL12/CXCR4 as a crucial driver of Wnt-Met tumors, given that compound-mutant mice also deficient in the CXCR4 gene were tumor resistant. Wnt-Met activation rapidly expanded a population of cancer-propagating cells, in which the two signaling systems control different functions, self-renewal and differentiation. Molecular therapy targeting Wnt, Met, and CXCR4 in mice significantly delayed tumor development. The expression of a Wnt-Met 322 gene signature was found to be predictive of poor survival of human patients with ER-negative breast cancers. Thus, targeting CXCR4 and its upstream activators, Wnt and Met, might provide an efficient strategy for breast cancer treatment.

  2. Chemokine receptors: attractive targets for drug discovery.

    Science.gov (United States)

    Godessart, Nuria

    2005-06-01

    Studies of two antibodies, efalizumab and natalizumab, have recently demonstrated that the blockade of leukocyte migration is of therapeutic benefit for the treatment of diseases such as psoriasis and multiple sclerosis. The role of chemokines in the control of cell traffic led to their receptors being considered one of the most promising family of targets aimed at disrupting cell recruitment in chronic inflammatory processes. Choosing the appropriate chemokine receptor for each disease was not easy, and the interpretation of target validation studies proved to be extremely difficult. Despite an intense effort in the search for chemokine receptor antagonists in the last decade, no compounds in advanced clinical trials exist as such. The inherent complexity of the family, the differences between the chemokine system in mice and men, and the species selectivity of small-molecule compounds could account for this fact. Pharmaceutical companies still believe in chemokine receptors as therapeutic targets, as demonstrated by the number of compounds reported to be in development. In the next years, the developmental progression of these compounds will reveal which target within the chemokine family is of real therapeutic value.

  3. CXC motif chemokine receptor 4 gene polymorphism and cancer risk

    Science.gov (United States)

    Wu, Yang; Zhang, Chun; Xu, Weizhang; Zhang, Jianzhong; Zheng, Yuxiao; Lu, Zipeng; Liu, Dongfang; Jiang, Kuirong

    2016-01-01

    Abstract Background: Previous epidemiological studies have reported the relationship between CXC motif chemokine receptor 4 (CXCR4) synonymous polymorphism (rs2228014), and risk of cancer, but the results remained conflicting and controversial. Therefore, this study was devised to evaluate the genetic effects of the rs2228014 polymorphism on cancer risk in a large meta-analysis. Methods: The computer-based databases (EMBASE, Web of Science, and PubMed) were searched for all relevant studies evaluating rs2228014 and susceptibility to cancer. In the analysis, pooled odds ratios (ORs) with its corresponding 95% confidence intervals (CIs) were calculated in 5 genetic models to assess the genetic risk. Egger regression and Begg funnel plots test were conducted to appraise the publication bias. Results: Data on rs2228014 polymorphism and overall cancer risk were available for 3684 cancer patients and 5114 healthy controls participating in 11 studies. Overall, a significantly increased risk of cancer was associated with rs2228014 polymorphism in homozygote model (OR = 2.01, 95% CI: 1.22–3.33) and in recessive model (OR = 1.97, 95% CI: 1.23–3.16). When stratified by ethnicity, the results were positive only in Asian populations (heterozygote model: OR = 1.36, 95% CI: 1.13–1.65; homozygote model: OR = 2.43, 95% CI: 1.21–4.91; dominant model: OR = 1.47, 95% CI: 1.13–1.90; recessive model: OR = 2.25, 95% CI: 1.13–4.48; and allele model: OR = 1.48, 95% CI: 1.10–1.99). Besides, in the subgroup analysis by source of control, the result was significant only in population-based control (homozygote model: OR = 2.39, 95% CI: 1.06–5.40; recessive model: pooled OR = 2.24, 95% CI: 1.02–4.96). Conclusion: In general, our results first indicated that the rs2228014 polymorphism in CXCR4 gene is correlated with an increased risk of cancer, especially among Asian ethnicity. Large, well-designed epidemiological studies are required to verify the current findings. PMID

  4. Expression of SDF-1 and CXCR4 transcript variants and CXCR7 in epithelial ovarian cancer.

    Science.gov (United States)

    Jaszczynska-Nowinka, Karolina; Rucinski, Marcin; Ziolkowska, Agnieszka; Markowska, Anna; Malendowicz, Ludwik K

    2014-05-01

    Chemokine stromal cell-derived factor-1 (SDF-1) and its receptors, CXCR4 and CXCR7, have been implicated in epithelial ovarian cancer progression and metastasis. However, limited data are available on the expression levels of SDF-1 and CXCR4 variants and CXCR7 in human epithelial ovarian cancer. The present study aimed to characterize the expression pattern and levels of SDF-1, CXCR4 and CXCR7 in normal human ovaries and epithelial ovarian cancer. The expression of SDF-1 and CXCR4 transcript variants and CXCR7 was determined by quantitative polymerase chain reaction (qPCR). Plasma SDF-1α levels were determined by commercially available EIA kits and cancer antigen 125 (CA 125) levels were quantified by automated microparticle enzyme immunosorbent assay. High expression levels of SDF-1 transcript variant 1 were identified in ovarian cancer and control ovaries. By contrast, in both groups the expression levels of SDF-1 transcript variants 3 and 4 were extremely low. Furthermore, SDF-1 variant 1 levels were notably higher in epithelial ovarian cancer than in control ovaries, while data for the remaining transcripts were similar in both groups. CXCR4 transcript variant 2 and CXCR7 expression levels in normal and neoplastic ovaries were similar. In both groups, CXCR4 transcript variant 2 was not detected. Plasma SDF-1α levels were notably higher in females with epithelial ovarian cancer than in the control ovaries. Elevated levels of blood SDF-1α were found prior to surgery, 6 days after surgery and following completion of the first chemotherapy course. These increases were independent of the type of epithelial ovarian cancer. Our results suggest that the expression of SDF-1 and the genes controlling alternative splicing are elevated in epithelial ovarian cancer, leading to an increased formation of SDF-1 variant 1. Elevated plasma SDF-1α levels in epithelial ovarian cancer patients are not associated with the presence of tumors and/or metastases, however reflect a

  5. Molecular Pharmacology of CXCR4 inhibition

    DEFF Research Database (Denmark)

    Steen, Anne; Rosenkilde, Mette Marie

    2012-01-01

    pharmacology of well-known CXCR4 antagonists in order to augment the potency and affinity and to increase the specificity of future CXCR4-targeting compounds. In this chapter, binding modes of CXCR4 antagonists that have been shown to mobilize stem cells are discussed. In addition, comparisons between results...

  6. Molecular Pharmacology of CXCR4 inhibition

    DEFF Research Database (Denmark)

    Steen, Anne; Rosenkilde, Mette Marie

    2012-01-01

    pharmacology of well-known CXCR4 antagonists in order to augment the potency and affinity and to increase the specificity of future CXCR4-targeting compounds. In this chapter, binding modes of CXCR4 antagonists that have been shown to mobilize stem cells are discussed. In addition, comparisons between results...

  7. Molecular piracy of chemokine receptors by herpesviruses.

    Science.gov (United States)

    Murphy, P M

    1994-01-01

    To succeed as a biological entity, viruses must exploit normal cellular functions and elude the host immune system; they often do so by molecular mimicry. One way that mimicry may occur is when viruses copy and modify host genes. The best studied examples of this are the oncogenes of RNA retroviruses, but a growing number of examples are also known for DNA viruses. So far they all come from just two groups of DNA viruses, the herpesviruses and poxviruses, and the majority of examples are for genes whose products regulate immune responses, such as cytokines, cytokine receptors, and complement control proteins. This review will focus on human and herpesvirus receptors for chemokines, a family of leukocyte chemoattractant and activating factors that are thought to be important mediators of inflammation. Although the biological roles of the viral chemokine receptor homologues are currently unknown, their connection to specific sets of chemokines has suggested a number of possible functions.

  8. The expression and clinical significance of SDF-1/CXCR4 in laryngeal cancer%SDF-1/CXCR4在喉癌组织中的表达及其临床意义

    Institute of Scientific and Technical Information of China (English)

    李文媛; 王莹; 李智刚; 金在顺

    2013-01-01

    Objective To investigate the relationship between the expression of stromal-derived factor-1 ( SDF-1 ),CXC chemokine receptor 4 ( CXCR4 ) and lymphangiogenesis,prognosis significance in patients with laryngeal cane-er. Methods The expressions of SDF-1 and CXCR4 in 45 specimens of the laryngeal cancer and 20 specimens of polyp of vocal cord tissues were detected by immunohistochemistry and real-time fluorescent quantitative PCR,and the correlation analysis was made between SDF-1,CXCR4 and clinical character,and judged their roles in laryngeal cancer prognosis by using Kaplan-Meier analysis. Results The expressions of SDF-1/CXCR protein and the mRNA were higher in laryngeal cancer tissue than in the polyp of vocal cord tissue ( P < 0. 05 ),the expressions of SDF-1 and CX- CR4 were significantly correlated with lymph node metastasis,lymphovascular invasion and TNM stage ( P < 0.05 ). The expressions of SDF -1 and CXCR protein in laryngeal cancer were positively correlated (P <0.05). The expression of SDF-1 and survival rate were negatively correlated ( P < 0.05 ) . Conclusion SDF-1/CXCR4 biological axis may play an important role in promoting the development of laryngeal cancer and lymph node metastasis . The high expression of SDF-1 may be helpful for judging the prognosis in laryngeal cancer .%目的 探讨趋化因子基质细胞衍生因子1(SDF-1)及其受体(CXC chemokine receptor 4,CXCR4)与喉癌病理特征及预后的关系.方法应用免疫组化法和实时荧光定量PCR方法检测SDF-1 及CXCR4在45例喉癌和20例声带息肉组织中的表达,并结合临床病理特征和生存资料进行相关分析.结果喉癌组SDF-1、CXCR4蛋白及 mRNA的表达较声带息肉组显著增加(P<0.05);SDF-1和CXCR4表达与喉癌淋巴结转移、淋巴管浸润、TNM临床分期有关(P<0.05).SDF-1和CXCR4蛋白在喉癌中的表达呈正相关(P<0.05),SDF-1阳性表达与生存率呈负相关(P<0.05).结论 SDF-1/CXCR4生物学轴促进喉癌的发

  9. Chemokine Receptors as Biomarkers in Multiple Sclerosis

    Directory of Open Access Journals (Sweden)

    Robert J. Fox

    2006-01-01

    Full Text Available Leukocyte infiltrates characterize tissue inflammation and are thought to be integral in the pathogenesis of multiple sclerosis (MS. This attribute underlines the importance of understanding mechanisms of leukocyte migration. Chemokines are secreted proteins which govern leukocyte trafficking into targeted organs. Chemokine receptors (CKR are differentially expressed on leukocytes and their modulation is a potential target for MS disease modifying therapies. Chemokines and their receptors are also potential biomarkers of both disease activity and response to treatment. We describe the fluctuations in CKR expression on peripheral leukocytes in a group of MS patients followed longitudinally for up to 36 months. We observed little fluctuation in CKR expression within each patient over time, despite considerable variability in CKR expression between patients. These observations suggest that individual patients have a CKR set point, and this set point varies from one patient to another. Evaluation of chemokines or chemokine receptors as biomarkers in MS will need to account for this individual variability in CKR expression.

  10. 骨肉瘤组织 eIF -1α和 CXCR4表达及其临床意义的研究%Expressions of HIF - 1α and CXCR4 in osteosarcoma and the significance

    Institute of Scientific and Technical Information of China (English)

    关国锋; 路遥; 马琼; 艳华; 杨连甲; 裘秀春; 周勇

    2014-01-01

    目的:研究缺氧诱导因子-1α(eIF -1α)和趋化因子受体4(CXCR4)蛋白在骨肉瘤组织中的表达情况,探讨它们与骨肉瘤临床病理因素的关系。方法:采用免疫组化 SP 法检测52例骨肉瘤及18例骨软骨瘤标本中 eIF -1α和 CXCR4的表达情况,对骨肉瘤组织中 eIF -1α和 CXCR4蛋白表达之间及其与临床病理参数的关系进行统计学分析。结果:eIF -1α和 CXCR4在骨肉瘤中的阳性表达率分别为88.46%和82.69%,与骨软骨瘤组织中两者阳性表达率相比(11.11%和16.67%),差异有统计学意义(P ﹤0.05)。eIF-1α和 CXCR4表达水平与骨肉瘤的转移和临床分期密切相关(P ﹤0.05),与性别、年龄、肿瘤体积及肿瘤分化程度无明显关系( P ﹥0.05)。eIF -1α阳性表达组的 CXCR4表达率(86.96%)显著高于阴性表达组(50%,P ﹤0.05),且 eIF -1α表达水平和 CXCR4呈正相关(r =0.468,P ﹤0.05);同时转移组病例的 eIF -1α和 CXCR4表达水平均高于无转移组病例(P ﹤0.05)。结论:eIF -1α、CXCR4高表达可能在骨肉瘤的恶性进展中发挥重要作用,并与骨肉瘤肺转移密切相关。联合检测 eIF -1α和 CXCR4蛋白的表达对于评估骨肉瘤的生物学行为,提高预后判断的准确性以及临床靶向性治疗有重要的指导意义。%Objective:To investigate the exPressions of hyPoxia - inducible factor - 1α(eIF - 1α)and CXC che-mokine recePtor 4(CXCR4)in osteosarcoma and their relationshiP with biological characteristics and clinical signifi-cance. Methods:The exPressions of eIF - 1α and CXCR4 were examined by SP immunohistochemical staining in 52 cases of osteosarcoma tissues and 18 cases of osteochondroma tissues and their association with clinicoPathological fea-tures was analyzed. Results:The Positive exPression rates of eIF - 1α and CXCR4 in osteosarcoma were 88. 46% and 82. 69% ,resPectively,which were significantly different

  11. Stimulation of oral fibroblast chemokine receptors identifies CCR3 and CCR4 as potential wound healing targets.

    Science.gov (United States)

    Buskermolen, Jeroen K; Roffel, Sanne; Gibbs, Susan

    2017-11-01

    The focus of this study was to determine which chemokine receptors are present on oral fibroblasts and whether these receptors influence proliferation, migration, and/or the release of wound healing mediators. This information may provide insight into the superior wound healing characteristics of the oral mucosa. The gingiva fibroblasts expressed 12 different chemokine receptors (CCR3, CCR4, CCR6, CCR9, CCR10, CXCR1, CXCR2, CXCR4, CXCR5, CXCR7, CX3CR1, and XCR1), as analyzed by flow cytometry. Fourteen corresponding chemokines (CCL5, CCL15, CCL20, CCL22, CCL25, CCL27, CCL28, CXCL1, CXCL8, CXCL11, CXCL12, CXCL13, CX3CL1, and XCL1) were used to study the activation of these receptors on gingiva fibroblasts. Twelve of these fourteen chemokines stimulated gingiva fibroblast migration (all except for CXCL8 and CXCL12). Five of the chemokines stimulated proliferation (CCL5/CCR3, CCL15/CCR3, CCL22/CCR4, CCL28/CCR3/CCR10, and XCL1/XCR1). Furthermore, CCL28/CCR3/CCR10 and CCL22/CCR4 stimulation increased IL-6 secretion and CCL28/CCR3/CCR10 together with CCL27/CCR10 upregulated HGF secretion. Moreover, TIMP-1 secretion was reduced by CCL15/CCR3. In conclusion, this in-vitro study identifies chemokine receptor-ligand pairs which may be used in future targeted wound healing strategies. In particular, we identified the chemokine receptors CCR3 and CCR4, and the mucosa specific chemokine CCL28, as having an predominant role in oral wound healing by increasing human gingiva fibroblast proliferation, migration, and the secretion of IL-6 and HGF and reducing the secretion of TIMP-1. © 2017 The Authors. Journal of Cellular Physiology Published by wiley periodicals, Inc.

  12. Intracellular CXCR4+ cell targeting with T22-empowered protein-only nanoparticles

    Directory of Open Access Journals (Sweden)

    Unzueta U

    2012-08-01

    Full Text Available Ugutz Unzueta,1–3 María Virtudes Céspedes,3,4 Neus Ferrer-Miralles,1–3 Isolda Casanova,3,4 Juan Cedano,5 José Luis Corchero,1–3 Joan Domingo-Espín,1–3 Antonio Villaverde,1–3 Ramón Mangues,3,4 Esther Vázquez1–31Institut de Biotecnologia i de Biomedicina, 2Departamento de Genètica i de Microbiologia, Universitat Autònoma de Barcelona, Bellaterra, Barcelona, 3CIBER en Bioingeniería, Biomateriales y Nanomedicina, Bellaterra, Barcelona, 4Oncogenesis and Antitumor Drug Group, Biomedical Research Institute Sant Pau, Hospital de la Santa Creu i Sant Pau, Barcelona, Spain; 5Laboratory of Immunology, Regional Norte, Universidad de la Republica, Salto, UruguayBackground: Cell-targeting peptides or proteins are appealing tools in nanomedicine and innovative medicines because they increase the local drug concentration and reduce potential side effects. CXC chemokine receptor 4 (CXCR4 is a cell surface marker associated with several severe human pathologies, including colorectal cancer, for which intracellular targeting agents are currently missing.Results: Four different peptides that bind CXCR4 were tested for their ability to internalize a green fluorescent protein-based reporter nanoparticle into CXCR4+ cells. Among them, only the 18 mer peptide T22, an engineered segment derivative of polyphemusin II from the horseshoe crab, efficiently penetrated target cells via a rapid, receptor-specific endosomal route. This resulted in accumulation of the reporter nanoparticle in a fully fluorescent and stable form in the perinuclear region of the target cells, without toxicity either in cell culture or in an in vivo model of metastatic colorectal cancer.Conclusion: Given the urgent demand for targeting agents in the research, diagnosis, and treatment of CXCR4-linked diseases, including colorectal cancer and human immunodeficiency virus infection, T22 appears to be a promising tag for the intracellular delivery of protein drugs, nanoparticles

  13. The chemokine SDF-1 regulates blastema formation during zebrafish fin regeneration.

    Science.gov (United States)

    Dufourcq, Pascale; Vriz, Sophie

    2006-10-01

    The work presented in this study focuses on blastema formation in epimorphic regeneration. We describe the expression pattern of Sdf1a and Sdf1b (the chemokines stromal-cell-derived factor-1a and 1b) and their two receptors Cxcr4a and Cxcr4b during zebrafish fin regeneration. We demonstrate that Sdf1a/Cxcr4a plays a critical role in fin regeneration and more precisely in epidermal cell proliferation, an important process for blastema formation. In mammals, a single cxcr4 gene is involved both in chemotaxis and cell proliferation and survival; we discuss in this study a possible functional division of the two cxcr4 zebrafish genes.

  14. Application of chemokine receptor antagonist with stents reduces local inflammation and suppresses cancer growth.

    Science.gov (United States)

    Mao, Ai-Wu; Jiang, Ting-Hui; Sun, Xian-Jun; Peng, Jian

    2015-11-01

    Severe pain and obstructive jaundice resulting from invasive cholangiocarcinoma or pancreatic carcinoma can be alleviated by implantation of biliary and duodenal stents. However, stents may cause local inflammation to have an adverse effect on the patients' condition and survival. So far, no efficient approaches have been applied to prevent the occurrence of stents-related inflammation. Here, we reported significantly higher levels of serum stromal cell-derived factor 1 (SDF-1) in the patients that developed stents-associated inflammation. A higher number of inflammatory cells have been detected in the cancer close to stent in the patients with high serum SDF-1. Since chemokine plays a pivotal role in the development of inflammation, we implanted an Alzet osmotic pump with the stents to gradually release AMD3100, a specific inhibitor binding of SDF-1 and its receptor C-X-C chemokine receptor 4 (CXCR4), at the site of stents in mice that had developed pancreatic cancer. We found that AMD3100 significantly reduced local inflammation and significantly inhibited cancer cell growth, resulting in improved survival of the mice that bore cancer. Moreover, the suppression of cancer growth may be conducted through modulation of CyclinD1, p21, and p27 in the cancer cells. Together, these data suggest that inhibition of chemokine signaling at the site of stents may substantially improve survival through suppression of stent-related inflammation and tumor growth.

  15. CXCL12 MODULATION OF CXCR4 AND CXCR7 ACTIVITY IN HUMAN GLIOBLASTOMA STEM-LIKE CELLS AND REGULATION OF THE TUMOR MICROENVIRONMENT

    Directory of Open Access Journals (Sweden)

    Roberto eWurth

    2014-05-01

    Full Text Available Chemokines are crucial autocrine and paracrine players in tumor development. In particular, CXCL12, through its receptors CXCR4 and CXCR7, affects tumor progression by controlling cancer cell survival, proliferation and migration, and, indirectly, via angiogenesis or recruiting immune cells.Glioblastoma (GBM is the most prevalent primary malignant brain tumor in adults and despite current multimodal therapies it remains almost incurable. The aggressive and recurrent phenotype of GBM is ascribed to high growth rate, invasiveness to normal brain, marked angiogenesis, ability to escape the immune system and resistance to standard of care therapies. Tumor molecular and cellular heterogeneity severely hinders GBM therapeutic improvement. In particular, a subpopulation of chemo- and radio-therapy resistant tumorigenic cancer stem–like cells (CSCs is believed to be the main responsible for tumor cell dissemination to the brain.GBM cells display heterogeneous expression levels of CXCR4 and CXCR7 that are overexpressed in CSCs, representing a molecular correlate for the invasive potential of GBM. The microenvironment contribution in GBM development is increasingly emphasized. An interplay exists between CSCs, differentiated GBM cells, and the microenvironment, mainly through secreted chemokines (e.g. CXCL12 causing recruitment of fibroblasts, endothelial, mesenchymal and inflammatory cells to the tumor, via specific receptors such as CXCR4.This review covers recent developments on the role of CXCL12/CXCR4-CXCR7 networks in GBM progression and the potential translational impact of their targeting. The biological and molecular understanding of the heterogeneous GBM cell behavior, phenotype and signaling is still limited. Progress in the identification of chemokine-dependent mechanisms that affect GBM cell survival, trafficking and chemo-attractive functions, opens new perspectives for development of more specific therapeutic approaches that include

  16. Lymphotropic Virions Affect Chemokine Receptor-Mediated Neural Signaling and Apoptosis: Implications for Human Immunodeficiency Virus Type 1-Associated Dementia

    Science.gov (United States)

    Zheng, Jialin; Ghorpade, Anuja; Niemann, Douglas; Cotter, Robin L.; Thylin, Michael R.; Epstein, Leon; Swartz, Jennifer M.; Shepard, Robin B.; Liu, Xiaojuan; Nukuna, Adeline; Gendelman, Howard E.

    1999-01-01

    Chemokine receptors pivotal for human immunodeficiency virus type 1 (HIV-1) infection in lymphocytes and macrophages (CCR3, CCR5, and CXCR4) are expressed on neural cells (microglia, astrocytes, and/or neurons). It is these cells which are damaged during progressive HIV-1 infection of the central nervous system. We theorize that viral coreceptors could effect neural cell damage during HIV-1-associated dementia (HAD) without simultaneously affecting viral replication. To these ends, we studied the ability of diverse viral strains to affect intracellular signaling and apoptosis of neurons, astrocytes, and monocyte-derived macrophages. Inhibition of cyclic AMP, activation of inositol 1,4,5-trisphosphate, and apoptosis were induced by diverse HIV-1 strains, principally in neurons. Virions from T-cell-tropic (T-tropic) strains (MN, IIIB, and Lai) produced the most significant alterations in signaling of neurons and astrocytes. The HIV-1 envelope glycoprotein, gp120, induced markedly less neural damage than purified virions. Macrophage-tropic (M-tropic) strains (ADA, JR-FL, Bal, MS-CSF, and DJV) produced the least neural damage, while 89.6, a dual-tropic HIV-1 strain, elicited intermediate neural cell damage. All T-tropic strain-mediated neuronal impairments were blocked by the CXCR4 antibody, 12G5. In contrast, the M-tropic strains were only partially blocked by 12G5. CXCR4-mediated neuronal apoptosis was confirmed in pure populations of rat cerebellar granule neurons and was blocked by HA1004, an inhibitor of calcium/calmodulin-dependent protein kinase II, protein kinase A, and protein kinase C. Taken together, these results suggest that progeny HIV-1 virions can influence neuronal signal transduction and apoptosis. This process occurs, in part, through CXCR4 and is independent of CD4 binding. T-tropic viruses that traffic in and out of the brain during progressive HIV-1 disease may play an important role in HAD neuropathogenesis. PMID:10482576

  17. Expression of the CXCL12/CXCR4 and CXCL16/CXCR6 axes in cervical intraepithelial neoplasia and cervical cancer

    Institute of Scientific and Technical Information of China (English)

    Yu Huang; Jia Zhang; Zhu-Mei Cui; Jing Zhao; Ye Zheng

    2013-01-01

    The chemokine CXCL12 is highly expressed in gynecologic tumors and is widely known to play a biologically relevant role in tumor growth and spread.Recent evidence suggests that CXCL16,a novel chemokine,is overexpressed in inflammation-associated tumors and mediates pro-tumorigenic effects of inflammation in prostate cancer.We therefore analyzed the expression of CXCL12 and CXCL16 and their respective receptors CXCR4 and CXCR6 in cervical intraepithelial neoplasia (CIN) and cervical cancer and further assessed their association with clinicopathologic features and outcomes.Tissue chip technology and immunohistochemistry were used to analyze the expression of CXCL12,CXCR4,CXCL16,and CXCR6 in healthy cervical tissue (21 cases),CIN (65 cases),and cervical carcinoma (60 cases).The association of protein expression with clinicopathologic features and overall survival was analyzed.These four proteins were clearly detected in membrane and cytoplasm of neoplastic epithelial cells,and their distribution and intensity of expression increased as neoplastic lesions progressed through CIN1,CIN2,and CIN3 to invasive cancer.Furthermore,the expression of CXCR4 was associated significantly with the histologic grade of cervical carcinoma,whereas the expression of CXCR6 was associated significantly with lymph node metastasis.In Kaplan-Meier analysis,patients with high CXCR6 expression had significantly shorter overall survival than did those with low CXCR6 expression.The elevated co-expression levels of CXCL12/CXCR4 and CXCL16/CXCR6 in CIN and cervical carcinoma suggest a durative process in cervical carcinoma development.Moreover,CXCR6 may be useful as a biomarker and a valuable prognostic factor for cervical cancer.

  18. Constitutive plasmacytoid dendritic cell migration to the splenic white pulp is cooperatively regulated by CCR7- and CXCR4-mediated signaling.

    Science.gov (United States)

    Umemoto, Eiji; Otani, Kazuhiro; Ikeno, Takashi; Verjan Garcia, Noel; Hayasaka, Haruko; Bai, Zhongbin; Jang, Myoung Ho; Tanaka, Toshiyuki; Nagasawa, Takashi; Ueda, Koichi; Miyasaka, Masayuki

    2012-07-01

    Although the spleen plays an important role in host defense against infection, the mechanism underlying the migration of the innate immune cells, plasmacytoid dendritic cells (pDCs), into the spleen remains ill defined. In this article, we report that pDCs constitutively migrate into the splenic white pulp (WP) in a manner dependent on the chemokine receptors CCR7 and CXCR4. In CCR7-deficient mice and CCR7 ligand-deficient mice, compared with wild-type (WT) mice, substantially fewer pDCs were found in the periarteriolar lymphoid sheath of the splenic WP under steady-state conditions. In addition, the migration of adoptively transferred CCR7-deficient pDCs into the WP was significantly worse than that of WT pDCs, supporting the idea that pDC trafficking to the splenic WP requires CCR7 signaling. WT pDCs responded to a CCR7 ligand with modest chemotaxis and ICAM-1 binding in vitro, and priming with the CCR7 ligand enabled the pDCs to migrate efficiently toward low concentrations of CXCL12 in a CXCR4-dependent manner, raising the possibility that CCR7 signaling enhances CXCR4-mediated pDC migration. In agreement with this hypothesis, CCL21 and CXCL12 were colocalized on fibroblastic reticular cells in the T cell zone and in the marginal zone bridging channels, through which pDCs appeared to enter the WP. Furthermore, functional blockage of CCR7 and CXCR4 abrogated pDC trafficking into the WP. Collectively, these results strongly suggest that pDCs employ both CCR7 and CXCR4 as critical chemokine receptors to migrate into the WP under steady-state conditions.

  19. A meta-analysis for CXCR4 as a prognostic marker and potential drug target in non-small cell lung cancer

    Directory of Open Access Journals (Sweden)

    Zhang C

    2015-06-01

    Full Text Available Changyuan Zhang,1,* Jie Li,2,* Yi Han,3 Jian Jiang4 1Department of Cardiothoracic Surgery, Inner Mongolia Autonomous Region People’s Hospital, Inner Mongolia; 2Department of Oncology, 3Department of Thoracic Surgery, Beijing Chest Hospital, 4Department of Thoracic Surgery, Beijing Tongren Hospital, Capital Medical University, Beijing, People’s Republic of China *These authors contributed equally to this work Background: Recent reports have shown that C-X-C chemokine receptor type 4 (CXCR4 is a candidate oncogene in several types of human tumors, including non-small cell lung cancer (NSCLC. However, the correlation between CXCR4 expression and clinicopathological characteristics of NSCLC remains controversial and has not been emphasized. The aim of this study is to quantitatively evaluate the association of CXCR4 expression with the incidence of NSCLC and clinicopathological characteristics by performing a meta-analysis.Methods: A detailed literature search was carried out for related research publications. Only articles in which CXCR4 expression was detected by immunohistochemical staining were included. Odds ratio (OR and hazard ratio (HR with 95% confidence intervals (CIs were calculated and summarized.Results: Final analysis of 1,872 NSCLC patients from 19 eligible studies was performed. We observed that CXCR4 expression was significantly higher in NSCLC than in normal lung tissue, based on the pooled OR from ten studies, including 678 NSCLCs and 189 normal lung tissues (OR =16.66, 95% CI =6.94–40.02, P<0.00001. CXCR4 expression was also significantly associated with clinical stages, metastatic status, and overall survival (OS in NSCLC patients. In addition, CXCR4 mRNA high expression was found to correlate with worse OS of all NSCLC patients followed for 20 years, HR =1.24, P=0.0047.Conclusion: The present meta-analysis indicated that CXCR4 protein expression is associated with an increased risk and worse survival in NSCLC patients

  20. Preferential suppression of CXCR4-specific strains of HIV-1 by antiviral therapy.

    Science.gov (United States)

    Philpott, S; Weiser, B; Anastos, K; Kitchen, C M; Robison, E; Meyer, W A; Sacks, H S; Mathur-Wagh, U; Brunner, C; Burger, H

    2001-02-01

    To initiate infection, HIV-1 requires a primary receptor, CD4, and a secondary receptor, principally the chemokine receptor CCR5 or CXCR4. Coreceptor usage plays a critical role in HIV-1 disease progression. HIV-1 transmitted in vivo generally uses CCR5 (R5), but later CXCR4 (X4) strains may emerge; this shift heralds CD4+ cell depletion and clinical deterioration. We asked whether antiretroviral therapy can shift HIV-1 populations back to R5 viruses after X4 strains have emerged, in part because treatment has been successful in slowing disease progression without uniformly suppressing plasma viremia. We analyzed the coreceptor usage of serial primary isolates from 15 women with advanced disease who demonstrated X4 viruses. Coreceptor usage was determined by using a HOS-CD4+ cell system, biological and molecular cloning, and sequencing the envelope gene V3 region. By constructing a mathematical model to measure the proportion of virus in a specimen using each coreceptor, we demonstrated that the predominant viral population shifted from X4 at baseline to R5 strains after treatment. Multivariate analyses showed that the shift was independent of changes in plasma HIV-1 RNA level and CD4+ cell count. Hence, combination therapy may lead to a change in phenotypic character as well as in the quantity of HIV-1. Shifts in coreceptor usage may thereby contribute to the clinical efficacy of anti-HIV drugs.

  1. Interleukin-17 (IL-17 Expression Is Reduced during Acute Myocardial Infarction: Role on Chemokine Receptor Expression in Monocytes and Their in Vitro Chemotaxis towards Chemokines

    Directory of Open Access Journals (Sweden)

    Guro Valen

    2012-11-01

    Full Text Available The roles of immune cells and their soluble products during myocardial infarction (MI are not completely understood. Here, we observed that the percentages of IL-17, but not IL-22, producing cells are reduced in mice splenocytes after developing MI. To correlate this finding with the functional activity of IL-17, we sought to determine its effect on monocytes. In particular, we presumed that this cytokine might affect the chemotaxis of monocytes important for cardiac inflammation and remodeling. We observed that IL-17 tends to reduce the expression of two major chemokine receptors involved in monocyte chemotaxis, namely CCR2 and CXCR4. Further analysis showed that monocytes pretreated with IL-17 have reduced in vitro chemotaxis towards the ligand for CCR2, i.e., MCP-1/CCL2, and the ligand for CXCR4, i.e., SDF-1α/CXCL12. Our results support the possibility that IL-17 may be beneficial in MI, and this could be due to its ability to inhibit the migration of monocytes.

  2. CXCL12/CXCR4: a symbiotic bridge linking cancer cells and their stromal neighbors in oncogenic communication networks.

    Science.gov (United States)

    Guo, F; Wang, Y; Liu, J; Mok, S C; Xue, F; Zhang, W

    2016-02-18

    Increasing evidence indicates that the tumor microenvironment has critical roles in all aspects of cancer biology, including growth, angiogenesis, metastasis and progression. Although chemokines and their receptors were originally identified as mediators of inflammatory diseases, it is being increasingly recognized that they serve as critical communication bridges between tumor cells and stromal cells to create a permissive microenvironment for tumor growth and metastasis. Thus, an important therapeutic strategy for cancer is to break this communication channel and isolate tumor cells for long-term elimination. Cytokine CXCL12 (also known as stromal-derived factor 1α) and its receptor CXCR4 represent the most promising actionable targets for this strategy. Both are overexpressed in various cancer types, and this aberrant expression strongly promotes proliferation, migration and invasion through multiple signal pathways. Several molecules that target CXCL12 or CXCR4 have been developed to interfere with tumor growth and metastasis. In this article, we review our current understanding of the CXCL12/CXCR4 axis in cancer tumorigenesis and progression and discuss its therapeutic implications.

  3. Loss of C-terminal α-helix decreased SDF-1α-mediated signaling and chemotaxis without influencing CXCR4 internalization

    Institute of Scientific and Technical Information of China (English)

    Shao-hui CAI; Yi TAN; Xian-da REN; Xiao-hong LI; Shao-xi CAI; Jun DU

    2004-01-01

    AIM: To investigate the possibility that a novel α-helix-defective mutant of stromal cell-derived factor-1α (SDF-1α) (SDF-1/54R) acts as an antagonist of CXC chemokine receptor 4 (CXCR4). METHODS: According to the genetic sequence of natural SDF- 1 α, a recombinant α-helix-defective mutant of SDF- 1 α was designed and some biologic characteristics of this mutant were demonstrated. The migration of Jurkat cells was assessed with chemotactic assay. ERK phosphorylation was analyzed by Western blot with a specific anti-phospho-ERK 1/2 antibody.Intracellular calcium influx was examined by flow cytometer with a calcium indicator dye Fluo-3AM. The CXCR4 on the cell surface was detected by flow cytometer with a PE conjoined anti-human CXCR4 antibody. RESULTS:Compared with native SDF-1α, SDF-1/54R displayed apparent decrease in chemotactic ability, ERK 1/2 activation,and intracellular calcium influx in Jurkat cells. However, the binding to CXCR4 and inducing CXCR4 internalization of SDF-1/54R did not change outstandingly. Moreover, a competitive inhibitory effect of SDF-1/54R on the migration of Jurkat cells induced by native SDF-1 α was confirmed. CONCLUSION: α-helix-defective mutant of SDF-1 α, SDF-1/54R that remained both the N-terminus and the central β-sheet region, decreased SDF-1 α-mediated signaling and chemotaxis but did not influence CXCR4 internalization, which suggested that SDF-1/54R might be developed as an anti-CHIV inhibitor with high biological potency and low side-effect.

  4. Chemokines and their receptors in central nervous system disease

    NARCIS (Netherlands)

    Biber, K; de Jong, EK; van Weering, HRJ; Boddeke, HWGM

    2006-01-01

    Almost a decade ago, it was discovered that the human deficiency virus (HIV) makes use of chemokine receptors to infect blood cells. This appreciation of the clinical relevance of specific chemokine receptors has initiated a considerable boost in the field of chemokine research. It is clear today th

  5. CXCR4 antagonist AMD3100 ameliorates thyroid damage in autoimmune thyroiditis in NOD.H‑2h⁴ mice.

    Science.gov (United States)

    Liu, Xin; Mao, Jinyuan; Han, Cheng; Peng, Shiqiao; Li, Chenyan; Jin, Ting; Fan, Chenling; Shan, Zhongyan; Teng, Weiping

    2016-04-01

    CXC chemokine ligand 12 (CXCL12) and its receptor, CXC chemokine receptor 4 (CXCR4), are upregulated in mice with autoimmune thyroid diseases. However, whether this interaction is involved in the pathophysiology of autoimmune thyroiditis (AIT) remains to be elucidated. In the present study, the effects of the CXCR4 antagonist, AMD3100, in an iodine‑induced autoimmune thyroiditis model were investigated. NOD.H‑2h4 mice were randomly separated into a control, AIT and AIT+AMD3100 groups. The mice were fed with 0.05% sodium iodide water for 8 weeks to induce AIT. The AMD3100‑treated mice were administered with the CXCR4 antagonist at a dose of 10 mg/kg intraperitoneally three times a week during the experimental period. The percentages of CD19+interleukin (IL)10+ B cells and CD4+IL10+ T cells, and the mRNA expression levels of IL10 in the splenocytes were reduced in the AIT group, compared with the control group, however, they increased following AMD3100 treatment, compared with the untreated AIT group. The percentages of CD4+ T cells, CD8+ T cells, CD19+ B cells and CD8+ interferon (IFN)γ+ T cells, and the mRNA expression levels of IFNγ increased in the AIT group, compared with the control group, however, these were reduced in the AMD3100 group, compared with the AIT group. The AMD3100‑treated mice also had lower serum thyroglobulin antibody titers and reduced lymphocytic infiltration in the thyroid, compared with the untreated AIT mice. These results suggested that inhibition of this chemokine axis may offer potential as a therapeutic target for the treatment of AIT.

  6. HIV-1 co-receptor usage based on V3 loop sequence analysis: preferential suppression of CXCR4 virus post HAART?

    Science.gov (United States)

    Jiao, Yanmei; Wang, Pengfei; Zhang, Hongwei; Zhang, Tong; Zhang, Yonghong; Zhu, Huanzhang; Wu, Hao

    2011-01-01

    Disease progression during human immunodeficiency virus type 1 (HIV-1) infection has been associated with a switch of viral coreceptor usage from CCR5 to CXCR4. The current study investigates the effect of anti retroviral therapy (ART) on the viral tropism in a group of patients based on the V3 loop sequence, in ART naïve patients prior to and 24 weeks after ART. Genomic DNA was extracted from the PBMCs of these patients, and the C2-V5 region of the HIV-1 env genes were cloned and sequenced. The coreceptor usage was predicated based on V3 loop amino acid sequences using Geno2pheno and PSSM programs. Our results indicate that following ART, the plasma viral loads of both CXCR4 and CCR5 viruses were significantly decreased. We observed a relatively higher ratio of R5 than X4 virus after 24 weeks of ART and both the positive charges and the net charges of the V3 regions were decreased significantly (p suppression of X4 virus. These data will help improve prognostic outcomes and help clinicians determine the course of treatment in patients who exhibit virologic failure while taking a CCR5 antagonist.

  7. Enhancing the Migration Ability of Mesenchymal Stromal Cells by Targeting the SDF-1/CXCR4 Axis

    Directory of Open Access Journals (Sweden)

    Leah A. Marquez-Curtis

    2013-01-01

    Full Text Available Mesenchymal stromal cells (MSCs are currently being investigated in numerous clinical trials of tissue repair and various immunological disorders based on their ability to secrete trophic factors and to modulate inflammatory responses. MSCs have been shown to migrate to sites of injury and inflammation in response to soluble mediators including the chemokine stromal cell-derived factor-(SDF-1, but during in vitro culture expansion MSCs lose surface expression of key homing receptors particularly of the SDF-1 receptor, CXCR4. Here we review studies on enhancement of SDF-1-directed migration of MSCs with the premise that their improved recruitment could translate to therapeutic benefits. We describe our studies on approaches to increase the CXCR4 expression in in vitro-expanded cord blood-derived MSCs, namely, transfection, using the commercial liposomal reagent IBAfect, chemical treatment with the histone deacetylase inhibitor valproic acid, and exposure to recombinant complement component C1q. These methodologies will be presented in the context of other cell targeting and delivery strategies that exploit pathways involved in MSC migration. Taken together, these findings indicate that MSCs can be manipulated in vitro to enhance their in vivo recruitment and efficacy for tissue repair.

  8. First-in-Human Experience of CXCR4-Directed Endoradiotherapy with 177Lu- and 90Y-Labeled Pentixather in Advanced-Stage Multiple Myeloma with Extensive Intra- and Extramedullary Disease.

    Science.gov (United States)

    Herrmann, Ken; Schottelius, Margret; Lapa, Constantin; Osl, Theresa; Poschenrieder, Andreas; Hänscheid, Heribert; Lückerath, Katharina; Schreder, Martin; Bluemel, Christina; Knott, Markus; Keller, Ulrich; Schirbel, Andreas; Samnick, Samuel; Lassmann, Michael; Kropf, Saskia; Buck, Andreas K; Einsele, Hermann; Wester, Hans-Juergen; Knop, Stefan

    2016-02-01

    Chemokine receptor 4 (CXCR4) is a key factor for tumor growth and metastasis in several types of human cancer. Based on promising experiences with a radiolabeled CXCR4 ligand ((68)Ga-pentixafor) for diagnostic receptor targeting, (177)Lu- and (90)Y-pentixather were recently developed as endoradiotherapeutic vectors. Here, we summarize the first-in-human experience in 3 heavily pretreated patients with intramedullary and extensive extramedullary manifestations of multiple myeloma undergoing CXCR4-directed endoradiotherapy. CXCR4 target expression was demonstrated by baseline (68)Ga-pentixafor PET. Each treatment was approved by the clinical ethics committee. Pretherapeutic (177)Lu-pentixather dosimetry was performed before (177)Lu-pentixather or (90)Y-pentixather treatment. Subsequently, patients underwent additional chemotherapy and autologous stem cell transplantation for bone marrow rescue. A remarkable therapeutic effect was visualized in 2 patients, who showed a significant reduction in (18)F-FDG uptake. CXCR4-targeted radiotherapy with pentixather appears to be a promising novel treatment option in combination with cytotoxic chemotherapy and autologous stem cell transplantation, especially for patients with advanced multiple myeloma. © 2016 by the Society of Nuclear Medicine and Molecular Imaging, Inc.

  9. Embelin Inhibits Invasion and Migration of MDA-MB-231 Breast Cancer Cells by Suppression of CXC Chemokine Receptor 4, Matrix Metalloproteinases-9/2, and Epithelial-Mesenchymal Transition.

    Science.gov (United States)

    Lee, Hanwool; Ko, Jeong-Hyeon; Baek, Seung Ho; Nam, Dongwoo; Lee, Seok Geun; Lee, Junhee; Yang, Woong Mo; Um, Jae-Young; Kim, Sung-Hoon; Shim, Bum Sang; Ahn, Kwang Seok

    2016-06-01

    Embelin (EB) is a benzoquinone derivative isolated from Embelia ribes Burm plant. Recent scientific evidence shows that EB induces apoptosis and inhibits migration and invasion in highly metastatic human breast cancer cells. However, the exact mechanisms of EB in tumor metastasis and invasion have not been fully elucidated. Here, we investigated the underlying mechanisms of antimetastatic activities of EB in breast cancer cells. The EB downregulated the chemokine receptor 4 (CXCR4) as well as matrix metalloproteinase (MMP)-9/2 expression and upregulated the tissue inhibitor of metalloproteinase 1 expression in MDA-MB-231 cells under noncytotoxic concentrations but not in MCF-7 cells. Additionally, EB inhibited the CXC motif chemokine ligand 12 induced invasion and migration activities of MDA-MB-231 cells. A detailed study of underlying mechanisms revealed that the regulation of the downregulation of CXCR4 was at the transcriptional level, as indicated by the downregulation of mRNA expression and suppression of nuclear factor-kappa B (NF-κB) activation. It further reduced the binding of NF-κB to the CXCR4 promoter. Besides, EB downregulated mesenchymal marker proteins (neural cadherin and vimentin) and concurrently upregulated epithelial markers (epithelial cadherin and occludin). Overall, these findings suggest that EB can abrogate breast cancer cell invasion and metastasis by suppression of CXCR4, MMP-9/2 expressions, and inhibition of epithelial-mesenchymal transition and thus may have a great potential to suppress metastasis of breast cancer. Copyright © 2016 John Wiley & Sons, Ltd.

  10. Analysis of SDF-1/CXCR4 pathway function in osteosarcoma and the regulating effect of ex-ogenous SDF-1 on osteosarcoma cells%骨肉瘤中 SDF-1/CXCR4通路功能分析及外源性给予 SDF-1对骨肉瘤细胞的调节作用

    Institute of Scientific and Technical Information of China (English)

    梁鼎天; 李泉旺

    2016-01-01

    [ABSTRACT]Objective:To study SDF-1/CXCR4 pathway function in osteosarcoma and the regulating effect of exogenous SDF-1 on osteosarcoma cells.Methods:Osteosarcoma tissue and adjacent tissue were collected to detect mRNA contents of SDF-1 (stromal cell-derived factor-1),CXCR4 (CXC chemokine receptor 4),Wnt,β-catenin,TCF and LEF;osteosarcoma MG63 cell lines were cultured,treated with SDF-1 and transfected with CXCR4-siRNA,and cell migration rate,number of in-vasive cells as well as mRNA contents of Wnt,β-catenin,TCF,LEF,c-myc,cyclinD1,MMP2,MMP9 and VEGF were de-tected.Results:The mRNA contents of SDF-1,CXCR4,Wnt,β-catenin,TCF and LEF in osteosarcoma tissue were signifi-cantly higher than those in adjacent tissue;cell migration rate,number of invasive cells as well as mRNA contents of Wnt,β-catenin,TCF,LEF,c-myc,cyclinD1,MMP2,MMP9 and VEGF in SDF-1 treatment group were higher than those in control group;cell migration rate,number of invasive cells as well as mRNA contents of Wnt,β-catenin,TCF,LEF,c-myc,cy-clinD1,MMP2,MMP9 and VEGF in SDF-1 +CXCR4 interference group were lower than those in SDF-1 treatment group. Conclusions:SDF-1/CXCR4 pathway function in osteosarcoma is enhanced,and exogenous SDF-1 can promote osteosarcoma cell migration and invasion and activate Wnt/β-catenin pathway through CXCR4.%目的::研究骨肉瘤中 SDF-1/CXCR4通路功能及外源性给予 SDF-1对骨肉瘤细胞的调节作用。方法:收集骨肉瘤组织和瘤旁组织,测定 SDF-1、CXCR4、Wnt、β-catenin、TCF、LEF 的 mRNA 含量;培养骨肉瘤 MG63细胞株,用 SDF-1处理、转染 CXCR4-siRNA,测定细胞迁移率、侵袭数目以及 Wnt、β-catenin、TCF、LEF、c-myc、cyclinD1、MMP2、MMP9、VEGF 的 mRNA 含量。结果:骨肉瘤组织中 SDF-1、CXCR4、Wnt、β-catenin、TCF、LEF 的 mRNA 含量均明显高于瘤旁组织;SDF-1处理组细胞的迁移率、侵袭数目以及 Wnt、β-catenin、TCF、LEF、c-myc、cyclinD1、MMP2、MMP9、VEGF 的 m

  11. CXCR4(+) CD45(-) Cells are Niche Forming for Osteoclastogenesis via the SDF-1, CXCL7, and CX3CL1 Signaling Pathways in Bone Marrow.

    Science.gov (United States)

    Goto, Yoh; Aoyama, Mineyoshi; Sekiya, Takeo; Kakita, Hiroki; Waguri-Nagaya, Yuko; Miyazawa, Ken; Asai, Kiyofumi; Goto, Shigemi

    2016-06-24

    Bone homeostasis comprises the balance between bone-forming osteoblasts and bone-resorbing osteoclasts (OCs), with an acceleration of osteoclastic bone resorption leading to osteoporosis. OCs can be generated from bone marrow cells (BMCs) under the tightly regulated local bone environment. However, it remained difficult to identify the critical cells responsible for providing an osteoclastogenesis niche. In this study, we used a fluorescence-activated cell sorting technique to determine the cell populations important for forming an appropriate microenvironment for osteoclastogenesis and to verify the associated interactions between osteoclast precursor cells and non-OCs. We isolated and removed a small cell population specific for osteoclastogenesis (CXCR4(+) CD45(-) ) from mouse BMCs and cultured the remaining cells with receptor activator of nuclear factor-kappa B ligand (RANKL) and macrophage-colony stimulating factor. The resulting cultures showed significantly less large osteoclast formation. Quantitative RT-PCR analysis revealed that these CXCR4(+) CD45(-) cells expressed low levels of RANK and RANKL, but high levels of critical chemokines including stromal cell derived factor 1 (SDF-1), chemokine (C-X-C motif) ligand 7 (CXCL7), and chemokine (C-X3-C motif) ligand 1 (CX3CL1). Furthermore, an SDF-1-specific antibody strongly suppressed OC formation in RAW264.7 cells and antibodies against SDF-1, CXCL7, and CX3CL1 suppressed OC formation in BMCs. These results suggest that isolated CXCR4(+) CD45(-) cells support an appropriate microenvironment for osteoclastogenesis with a direct effect on the cells expressing SDF-1, CXCL7, and CX3CL1 receptors. The regulation of CXCR4(+) CD45(-) cell function might therefore inform therapeutic strategies for diseases involving loss of bone homeostasis. Stem Cells 2016.

  12. Effect of CCR7, CXCR4 and VEGF-C on the lymph node metastasis of human pancreatic ductal adenocarcinoma.

    Science.gov (United States)

    Guo, Jinghui; Lou, Wenhui; Ji, Yuan; Zhang, Shuncai

    2013-05-01

    The aim of the present study was to investigate the association between the expression of chemokine receptors CCR7 and CXCR4 and vascular endothelial growth factor (VEGF)-C and the lymph node metastasis of pancreatic ductal adenocarcinoma (PDAC). The mRNA transcription levels of CCR7, CXCR4 and VEGF-C were measured in 24 specimens by real-time reverse transcription (RT)-PCR, while the protein expression levels were measured in 65 specimens by immuohistochemistry. Professional software for pathological image manipulation (Image Pro Plus 6.0) was used to quantitate the results of the immunohistochemical staining. The mRNA and protein expression levels of CCR7, CXCR4 and VEGF-C were all significantly higher in the cancer samples compared with those in the adjacent normal tissue. The CCR7 and VEGF-C mRNA and protein expression levels were significantly higher in the patients with cancer types exhibiting lymph node metastasis and an advanced International Union Against Cancer (UICC) stage (PCCR7 expression (PCCR7 and VEGF-C (P0.05), however the strong positive expression of CCR7 and VEGF-C was significantly associated with the lymph node metastasis of PDAC.

  13. Evaluating the methylation status of CXCR4 promoter: A cost-effective and sensitive two-step PCR method.

    Science.gov (United States)

    Bianchessi, Valentina; Lauri, Andrea; Vigorelli, Vera; Toia, Martina; Vinci, Maria Cristina

    2017-02-15

    The chemokine receptor CXCR4 plays a key role in the bone marrow microenvironment maintenance and in the hematopoietic stem and progenitor cells migration. In addition, CXCR4 is expressed in a broad spectrum of solid tumors where its methylation state has been recently proposed as a biomarker for cancer prognosis. To evaluate methylation status of CXCR4 promoter we developed a sensitive, accurate, specific and cost-effective two-step PCR method that does not require any specific equipment other than a conventional real-time PCR instrument. The principle of the technique relies on a novel normalization strategy which allows the detection and quantification of small methylation differences among pre-amplified DNA samples deriving from low amount of starting material. In addition, the analysis of melting curve profiles of PCR products provides additional information about the methylation status of CpG sites in between the primers. Finally, the principle of this technique can potentially be adapted for the investigation of the methylation status of any other DNA region.

  14. Epigenetic Silencing of CXCR4 Promotes Loss of Cell Adhesion in Cervical Cancer

    Directory of Open Access Journals (Sweden)

    Suresh Singh Yadav

    2014-01-01

    Full Text Available In the network of chemokine signaling pathways, recent reports have described the SDF-1α/CXCR4 axis and its role in cancer progression and metastasis. Interestingly, we found downregulation of CXCR4 at both transcript and protein level in cervical cancer cell lines and primary tumors. We also found CXCR4 promoter hypermethylation in cervical cancer cell lines and primary biopsy samples. DNA hypomethylating drug 5-AZA-2′-deoxycytidine and histone deacetylase inhibitor Trichostatin A treatments in cell lines reactivate both CXCR4 transcription and protein expression. Cell adhesion assay demonstrated that autocrine SDF-1α promotes the loss of cell adhesion while paracrine SDF-1α predominantly protects the normal cervical cells from loss of cell adhesion. Cervical cancer cell line C-33A having increased expression of CXCR4 after TSA treatment showed increased cell adhesion by paracrine source of SDF-1α in comparison to untreated C-33A. These findings demonstrate the first evidence that epigenetic silencing of CXCR4 makes the cells inefficient to respond to the paracrine source of SDF-1α leading to loss of cell adhesion, one of the key events in metastases and progression of the disease. Our results provide novel insight of SDF-1α/CXCR4 signaling in tumor microenvironment which may be promising to further delineate molecular mechanism of cervical carcinogenesis.

  15. Sitagliptin, a dipeptidyl peptidase-4 inhibitor, increases the number of circulating CD34⁺CXCR4⁺ cells in patients with type 2 diabetes.

    Science.gov (United States)

    Aso, Yoshimasa; Jojima, T; Iijima, T; Suzuki, K; Terasawa, T; Fukushima, M; Momobayashi, A; Hara, K; Takebayashi, K; Kasai, K; Inukai, T

    2015-12-01

    We investigated the effects of sitagliptin, a dipeptidyl peptidase (DPP)-4 inhibitor, on the number of circulating CD34(+)CXCR4(+)cells, a candidate for endothelial progenitor cells (EPCs), plasma levels of stromal cell-derived factor (SDF)-1α, a ligand for CXCR4 receptor and a substrate for DPP-4, and plasma levels of interferon-inducible protein (IP)-10, for a substrate for DPP-4, in patients with type 2 diabetes. We studied 30 consecutive patients with type 2 diabetes who had poor glycemic control despite treatment with metformin and/or sulfonylurea. Thirty diabetic patients were randomized in a 2:1 ratio into a sitagliptin (50 mg/day) treatment group or an active placebo group (glimepiride 1 mg/day) for 12 weeks. Both groups showed similar improvements in glycemic control. The number of circulating CD34(+)CXCR4(+) cells was increased from 30.5 (20.0, 47.0)/10(6) cells at baseline to 55.5 (31.5, 80.5)/10(6) cells at 12 weeks of treatment with 50 mg/day sitagliptin (P = 0.0014), while showing no significant changes in patients treated with glimepiride. Plasma levels of SDF-1α and IP-10, both physiological substrates of endogenous DPP-4 and chemokines, were significantly decreased at 12 weeks of sitagliptin treatment. In conclusion, treatment with sitagliptin increased the number of circulating CD34(+)CXCR4(+) cells by approximately 2-fold in patients with type 2 diabetes.

  16. SDF-1/CXCR4 axis induces human dental pulp stem cell migration through FAK/PI3K/Akt and GSK3β/β-catenin pathways.

    Science.gov (United States)

    Li, Mingwei; Sun, Xuefei; Ma, Liang; Jin, Lu; Zhang, Wenfei; Xiao, Min; Yu, Qing

    2017-01-09

    SDF-1 (stromal cell derived factor-1) has been found to be widely expressed during dental pulp inflammation, while hDPSCs (human dental pulp stem cells) contribute to the repair of dental pulp. We showed that the migration of hDPSCs was induced by SDF-1 in a concentration-dependent manner and could be inhibited with siCXCR4 (C-X-C chemokine receptor type 4) and siCDC42 (cell division control protein 42), as well as drug inhibitors such as AMD3100 (antagonist of CXCR4), LY294002 (inhibitor of PI3K) and PF573228 (inhibitor of FAK). It was also confirmed that SDF-1 regulated the phosphorylation of FAK (focal adhesion kinases) on cell membranes and the translocation of β-catenin into the cell nucleus. Subsequent experiments confirmed that the expression of CXCR4 and β-catenin and the phosphorylation of FAK, PI3K (phosphoinositide 3-kinase), Akt and GSK3β (glycogen synthase kinase-3β) were altered significantly with SDF-1 stimulation. FAK and PI3K worked in coordination during this process. Our findings provide direct evidence that SDF-1/CXCR4 axis induces hDPSCs migration through FAK/PI3K/Akt and GSK3β/β-catenin pathways, implicating a novel mechanism of dental pulp repair and a possible application of SDF-1 for the treatment of pulpitis.

  17. Mechanisms of AEG-1 and CXCR4 gene expression regulating the epithelial-mesenchymal transition pathway involved in brain metastases of breast cancer.

    Science.gov (United States)

    Chen, Yanjun; Wang, Xinjun

    2017-01-01

    To study the astrocyte elevated gene (AEG)-1 in breast cancer and the mechanism of the chemokine receptor CXCR4 regulating the epithelial-mesenchymal transition (EMT) involved in brain metastases of breast cancer. A total of 20 breast cancer patients with and 40 without brain metastases were recruited. The expressions of AEG-1, CXCR4, E-cadherin, N-cadherin and α-SMA were detected by immunohistochemical staining, real-time (RT) quantitative (q) PCR and Western blot respectively in cancer and adjacent normal tissues. The expressions detected in the adjacent normal tissues from both groups showed no significant difference (p>0.05). In the group with brain metastases, AEG-1, CXCR4, N-cadherin, α-SMA, mRNA and the relative expression level of protein were higher than those of patients without brain metastases, while E-cadherin showed the opposite trend. AEG-1 and CXCR4 activate and regulate the EMT pathway to participate in brain metastases.

  18. 鼻咽癌组织中CCR7和CXCR4的表达及其临床意义%Expressions and clinical significance of CXCR4 and CCR7 in nasopharyngeal carcinoma

    Institute of Scientific and Technical Information of China (English)

    郑大勇; 董少婷; 陈锦章; 吕成伟; 黄振华; 黄娜; 石敏

    2014-01-01

    Objective To explore the expression of CXC chemokine receptor-4 (CXCR4) and CC chemo-kine receptor-7 (CCR7) in nasopharyngeal carcinoma (NPC) and its clinical significance. Methods Sixty patients with NPC admitted in our hospital from January 2012 to October 2013 were randomly selected for NPC tissue, which was assigned as the disease group. Another 30 cases with nasopharyngeal inflammation were selected as con-trol group for normal nasopharyngeal tissue. CXCR4 and CCR7 in two groups were detected with expression by im-munohistochemistry. Results The positive expression cases of CCR7 and CXCR4 in the disease group were 32 cases and 27 cases respectively, which were higher than those in the control group with 6 cases and 4 cases, and there were statistically significant different (P<0.05). The positive expression of CCR7 and CXCR4 inⅢstage andⅣstage were 22 cases and 16 cases, which were higher than those inⅠstage andⅡstage with 10 cases and 11 cas-es, and the difference has statistical significance (P<0.05). The positive expression of CCR7 in M1 stage was 24, which was higher than that in M0 stage with 8 cases, and the difference was statistically significant (P<0.05). The positive expression of CCR7 and CXCR4 in patients with lymph node metastasis were 23 cases and 24 cases, which were higher than in patients without metastasis with 9 and 3 cases, and the difference was statistically significant (P<0.05). Conclusion The positive expressions of CCR7 and CXCR4 in patients with NPC were significantly high-er than those in non-carcinoma tissue. It is related with clinical stage and lymph node metastasis. CXCR4 and CCR7 play important roles in the occurrence and development of nasopharyngeal carcinoma.%目的:探讨CXC族趋化因子受体4(CXCR4)和CC族趋化因子受体7(CCR7)在鼻咽癌(NPC)组织中的表达及其临床意义。方法随机选择2012年1月至2013年10月本院NPC患者60例,取其鼻咽癌组织(病例组),选

  19. Chemokine receptor expression in tumour islets and stroma in non-small cell lung cancer

    Directory of Open Access Journals (Sweden)

    Shikotra Aarti

    2010-04-01

    Full Text Available Abstract Background We have previously demonstrated that tumour islet infiltration by macrophages is associated with extended survival (ES in NSCLC. We therefore hypothesised that patients with improved survival would have high tumour islet expression of chemokine receptors known to be associated with favourable prognosis in cancer. This study investigated chemokine receptor expression in the tumour islets and stroma in NSCLC. Methods We used immunohistochemistry to identify cells expressing CXCR1, CXCR2, CXCR3, CXCR4, CXCR5 and CCR1 in the tumour islets and stroma in 20 patients with surgically resected NSCLC. Correlations were made with macrophage and mast cell expression. Results There was increased expression of CXCR2, CXCR3, and CCR1 in the tumour islets of ES compared with poor survival (PS patients (p = 0.007, 0.01, and 0.002, respectively. There was an association between 5 year survival and tumour islet CXCR2, CXCR3 and CCR1 density (p = 0.02, 0.003 and s = 0.520, p = 0.02 and between mast cell density and CXCR3 expression (rs = 0.499, p = 0.03 in the tumour islets. Conclusion Above median expression of CXCR2, CXCR3 and CCR1 in the tumour islets is associated with increased survival in NSCLC, and expression of CXCR3 correlates with increased macrophage and mast cell infiltration in the tumour islets.

  20. Targeting the CD20 and CXCR4 pathways in non-hodgkin lymphoma with rituximab and high-affinity CXCR4 antagonist BKT140.

    Science.gov (United States)

    Beider, Katia; Ribakovsky, Elena; Abraham, Michal; Wald, Hanna; Weiss, Lola; Rosenberg, Evgenia; Galun, Eithan; Avigdor, Abraham; Eizenberg, Orly; Peled, Amnon; Nagler, Arnon

    2013-07-01

    Chemokine axis CXCR4/CXCL12 is critically involved in the survival and trafficking of normal and malignant B lymphocytes. Here, we investigated the effect of high-affinity CXCR4 antagonist BKT140 on lymphoma cell growth and rituximab-induced cytotoxicity in vitro and in vivo. In vitro efficacy of BKT140 alone or in combination with rituximab was determined in non-Hodgkin lymphoma (NHL) cell lines and primary samples from bone marrow aspirates of patients with NHL. In vivo efficacy was evaluated in xenograft models of localized and disseminated NHL with bone marrow involvement. Antagonizing CXCR4 with BKT140 resulted in significant inhibition of CD20+ lymphoma cell growth and in the induction of cell death, respectively. Combination of BKT140 with rituximab significantly enhanced the apoptosis against the lymphoma cells in a dose-dependent manner. Moreover, rituximab induced CXCR4 expression in lymphoma cell lines and primary lymphoma cells, suggesting the possible interaction between CD20 and CXCR4 pathways in NHL. Primary bone marrow stromal cells (BMSC) further increased CXCR4 expression and protected NHL cells from rituximab-induced apoptosis, whereas BKT140 abrogated this protective effect. Furthermore, BKT140 showed efficient antilymphoma activity in vivo in the xenograft model of disseminated NHL with bone marrow involvement. BKT140 treatment inhibited the local tumor progression and significantly reduced the number of NHL cells in the bone marrow. Combined treatment of BKT140 with rituximab further decreased the number of viable lymphoma cells in the bone marrow, achieving 93% reduction. These findings suggest the possible role of CXCR4 in NHL progression and response to rituximab and provide the scientific basis for the development of novel CXCR4-targeted therapies for refractory NHL. ©2013 AACR.

  1. Implications of chemokines, chemokine receptors, and inflammatory lipids in atherosclerosis.

    Science.gov (United States)

    Rolin, Johannes; Maghazachi, Azzam A

    2014-04-01

    Chemokines are a diverse group of molecules with important implications for the development of solid tissues and normal function of the immune system. However, change of the conditions for such a complex system can have important and dangerous consequences leading to diseases. The specific implications of the various chemokines in diseases have been elucidated in the last few years, prompting hope of manipulating this system for therapy or prevention of diseases. On the other hand, inflammatory lipids are biologically active molecules with crucial impacts on the function of various cell types, including immune cells in health and disease. Here, we describe how these lipids affect the chemokine system and how they interact with chemokines to shape chronic inflammation in the case of atherosclerosis.

  2. Multiplex detection of homo- and heterodimerization of g protein-coupled receptors by proximity biotinylation.

    Directory of Open Access Journals (Sweden)

    Elisabeth Steel

    Full Text Available Dimerization of G protein-coupled receptors (GPCRs represents a potential mechanism by which GPCR functions are regulated. Several resonance energy transfer (RET-based methods have revealed GPCR homo- and heterodimerization. However, interpretation of an increase in FRET efficiency could be attributed to either dimerization/oligomerization events or conformational changes within an already dimerized/oligomerized receptor complex. Furthermore, RET-based methods can only measure pairwise dimerization, and cannot easily achieve multiplex detection. In this study, we applied proximity-based biotinylation for detecting receptor dimerization by utilizing a specific enzyme-substrate pair that are fused to GPCRs. The biotin ligase BirA is fused to CXCR4 and site-specifically biotinylates an acceptor peptide (AP in the presence of biotin. As a test case for our newly developed assay, we have characterized the homo-dimerization of chemokine receptor CXCR4 and heterodimerization of CXCR4 with CCR2 or CCR5. The degree of biotinylation varies with the amount of GPCR-AP as well as biotinylation time. Using enzyme/substrate receptor pairs and measuring receptor biotinylation, we demonstrate that CXCR4 can homo-dimerize and hetero-dimerize with CCR2 and CCR5. The effect of CXCL12, agonist for CXCR4, was found to decrease surface biotinylation of CXCR4-AP. This effect is due to a combination of CXCR4 endocytosis and stabilization of CXCR4 homodimers. Finally, when CXCR4-AP, CCR2-AP, and CCR5-AP were expressed together, we observed CXCR4-CXCR4 homodimers and CXCR4-CCR2 and CXCR4-CCR5 heterodimers. The newly developed assay opens new opportunity for multiplex detection for GPCR homo- and heterodimerization within the same cellular context.

  3. CXCR4-antagonist Peptide R-liposomes for combined therapy against lung metastasis

    Science.gov (United States)

    Ieranò, Caterina; Portella, Luigi; Lusa, Sara; Salzano, Giuseppina; D'Alterio, Crescenzo; Napolitano, Maria; Buoncervello, Maria; Macchia, Daniele; Spada, Massimo; Barbieri, Antonio; Luciano, Antonio; Barone, Maria Vittoria; Gabriele, Lucia; Caraglia, Michele; Arra, Claudio; De Rosa, Giuseppe; Scala, Stefania

    2016-03-01

    The chemokine CXCL12 activates CXCR4, initiating multiple pathways that control immune cell trafficking, angiogenesis and embryogenesis; CXCR4 is also overexpressed in multiple tumors affecting metastatic dissemination. While there has been great enthusiasm for exploiting the CXCR4-CXCL12 axis as a target in cancer therapy, to date the promise has yet to be fulfilled. A new class of CXCR4-antagonist cyclic peptides was recently developed and the compound named Peptide R was identified as the most active. With the intent to improve the efficacy and biodistribution of Peptide R, stealth liposomes decorated with Peptide R were developed (PL-Peptide R). In vitro PL-Peptide R efficiently inhibited CXCR4-dependent migration and in vivo it significantly reduced lung metastases and increased overall survival in B16-CXCR4 injected C57BL/6 mice. To evaluate if PL-Peptide R could also be a drug delivery system for CXCR4 expressing tumors, the PL-Peptide R was loaded with doxorubicin (DOX) (PL-Peptide R-DOX). PL-Peptide R-DOX efficiently delivered DOX to CXCR4 expressing cell lines with a consequent decrease in the DOX IC50 efficient dose. In vivo, B16-CXCR4 injected C57BL/6 mice treated with PL-Peptide R-DOX developed fewer lung metastases compared to PL-DOX treated mice. This work provides the proof-of-concept to prevent metastasis by using combined nanomedicine.The chemokine CXCL12 activates CXCR4, initiating multiple pathways that control immune cell trafficking, angiogenesis and embryogenesis; CXCR4 is also overexpressed in multiple tumors affecting metastatic dissemination. While there has been great enthusiasm for exploiting the CXCR4-CXCL12 axis as a target in cancer therapy, to date the promise has yet to be fulfilled. A new class of CXCR4-antagonist cyclic peptides was recently developed and the compound named Peptide R was identified as the most active. With the intent to improve the efficacy and biodistribution of Peptide R, stealth liposomes decorated with Peptide

  4. BMP signaling protects telencephalic fate by repressing eye identity and its Cxcr4-dependent morphogenesis.

    Science.gov (United States)

    Bielen, Holger; Houart, Corinne

    2012-10-16

    Depletion of Wnt signaling is a major requirement for the induction of the anterior prosencephalon. However, the molecular events driving the differential regionalization of this area into eye-field and telencephalon fates are still unknown. Here we show that the BMP pathway is active in the anterior neural ectoderm during late blastula to early gastrula stage in zebrafish. Bmp2b mutants and mosaic loss-of-function experiments reveal that BMP acts as a repressor of eye-field fate through inhibition of its key transcription factor Rx3, thereby protecting the future telencephalon from acquiring eye identity. This BMP-driven mechanism initiates the establishment of the telencephalon prior to the involvement of Wnt antagonists from the anterior neural border. Furthermore, we demonstrate that Rx3 and BMP are respectively required to maintain and restrict the chemokine receptor cxcr4a, which in turn contributes to the morphogenetic separation of eye-field and telencephalic cells during early neurulation.

  5. CXCR4/CXCL12 in Non-Small-Cell Lung Cancer Metastasis to the Brain

    Directory of Open Access Journals (Sweden)

    Sebastiano Cavallaro

    2013-01-01

    Full Text Available Lung cancer represents the leading cause of cancer-related mortality throughout the world. Patients die of local progression, disseminated disease, or both. At least one third of the people with lung cancer develop brain metastases at some point during their disease, even often before the diagnosis of lung cancer is made. The high rate of brain metastasis makes lung cancer the most common type of tumor to spread to the brain. It is critical to understand the biologic basis of brain metastases to develop novel diagnostic and therapeutic approaches. This review will focus on the emerging data supporting the involvement of the chemokine CXCL12 and its receptor CXCR4 in the brain metastatic evolution of non-small-cell lung cancer (NSCLC and the pharmacological tools that may be used to interfere with this signaling axis.

  6. Design, synthesis, and biological evaluation of CXCR4 ligands.

    Science.gov (United States)

    Mona, Christine E; Besserer-Offroy, Élie; Cabana, Jérôme; Leduc, Richard; Lavigne, Pierre; Heveker, Nikolaus; Marsault, Éric; Escher, Emanuel

    2016-11-02

    A combination of the CXCR4 inverse agonist T140 with N-terminal CXCL12 oligopeptides has produced the first nanomolar synthetic CXCR4 agonists. In these agonists, the inverse agonistic portion provides affinity whereas the N-terminal CXCL12 sequence induces receptor activation. Several CXCR4 crystal structures exist with either CVX15, an inverse agonist closely related to T140 and IT1t, a small molecule; we therefore attempted to produce another CXCL12 oligopeptide combination with IT1t. For this purpose, a primary amino group was introduced by total synthesis into one of the methyl groups of IT1t, serving as an anchoring point for the oligopeptide graft. The introduction of the oligopeptides on this analog however yielded antagonists, one compound displaying high affinity. On the other hand, the amino-substituted analogue itself proved to be an inverse agonist with a binding affinity of 2.6 nM compared to 11.5 nM for IT1t. This IT1t-like analog is hitherto one of the most potent non-peptidic CXCR4 inverse agonists reported.

  7. Inhibition of CXCR4 activity with AMD3100 decreases invasion of human colorectal cancer cells in vitro

    Institute of Scientific and Technical Information of China (English)

    Ji-Kun Li; Liang Yu; Yun Shen; Li-Sheng Zhou; Yi-Cheng Wang; Jian-Hai Zhang

    2008-01-01

    AIM: To investigate the effect and mechanism of blockade of the CXC chemokine receptor-4 (CXCR4) signaling pathway by AMD3100, a small non-peptide CXCR4 inhibitor, on invasion and metastasis of colorectal cancer cells in vitro.METHODS: Human colorectal cancer cell line SW480 was treated with AMD3100 at different final concentrations.3-(4,5-dimethylthiazole-2-yl)-2.5-dipheny-ltetrazolium bromide (MTT) assay was used to detect the effect of AMD3100 on cell proliferation. The invasion ability of SW480 cells was determined by cell invasion assay kit.In the presence of AMD3100, the CXCL12-mediated migratory response of SW480 cells was tested by classical chemotaxis assays. RT-PCR analysis and Western blotting were used to detect the expression of vascular endothelial growth factor (VEGF), matrix metalloproteinase-2 (MMP-2)and -9 (MMP-9) in SW480 cells.RESULTS: Cell viability was significantly suppressed by AMD3100 in a dose-dependent manner. AMD3100 (100and 1000 ng/mL) significantly inhibited the invasion ability of SW480 cells. Treatment with AMD3100markedly reduced the expression of VEGF and MMP-9but not MMP-2 in SW480 cells.CONCLUSION: The CXCL12/CXCR4 system is an important mediator of proliferation and invasion of CXCR4-expressing colorectal cancer cells, AMD3100inhibited invasion and metastasis activity of the colorectal cancer cell line SW480 through down-regulation of VEGF and MMP-9 expression.

  8. 胃癌原发灶中Snail和CXCR4的表达及其与临床病理特征和预后的关系%Expression of Snail and CXCR4 in primary iesion and its relationship with clinicopathological profiles and prognosis in gastric cancer

    Institute of Scientific and Technical Information of China (English)

    陈李骏; 蔡成; 俞继卫; 吴巨钢; 陆瑞祺; 姜波健

    2013-01-01

    Objective To investigate the clinicopathologic characters and prognostic value of epithelial mesenchymal transition (EMT) related proteins Snail and chemokine receptors 4(CXCR4) in gastric cancer.Methods The expressions of Snail and CXCR4 in the gastric tissues of 50 patients with gastric cancer were detected by Immunohistochemistry.The relation between the expressions of Snail and CXCR4 and the clinicopathologic characters were analyzed.The relative relationship between Snail expression and CXCR4 expression were identified by Spearman method.The correlation between the expressions of Snail and CXCR4 with the survival was analyzed by Kaplan-Meier method.Results The expression of Snail and CXCR4 expression were positive in 31 of 50 cases (62%) and 29 of 50 cases (58%) respectively.The expression levels of Snail and CXCR4 in the gastric cancer patients with diameter more than 5 cm,worse tissue differentiation,vascular invasion,lymphatic vessel invasion,lymph nodes metastasis,and T3 + T4 staging were significantly higher than those in the patients with diameter less than 5 cm,without vascular invasion,lymphatic vessel invasion,lymph nodes metastasis,and T1 + T2 staging (P < 0.05).The Expression of Snail and CXCR4 was positively Correlated(r =0.330,P =0.014).The co-expression of Snail and CXCR4 was significantly associated with poorer prognosis and was applied as an independent prognostic factor for gastric cancer (P =0.001).Conclusions The co-expression of Snail and CXCR4 was the independent prognostic factor for gastric cancer.The combining effect of EMT and CXCR4 may promote the progressions and metastasis of gastric cancer.Therefore,it may be of an effective way for the metastasis of gastric cancer to adjust these targets of the Snail and CXCR4.%目的 研究趋化因子受体4(CXCR4)与上皮间质转化(EMT)相关因子Snail表达与胃癌临床病理特征、预后的关系.方法 利用免疫组化方法检测50例胃癌组织中CXCR4和Snail的表达,分析Snail和CXCR

  9. Suppression of CCR5- but not CXCR4-tropic HIV-1 in lymphoid tissue by human herpesvirus 6.

    Science.gov (United States)

    Grivel, J C; Ito, Y; Fagà, G; Santoro, F; Shaheen, F; Malnati, M S; Fitzgerald, W; Lusso, P; Margolis, L

    2001-11-01

    HIV-1 infects target cells via a receptor complex formed by CD4 and a chemokine receptor, primarily CCR5 or CXCR4 (ref. 1). Commonly, HIV-1 transmission is mediated by CCR5-tropic variants, also designated slow/low, non-syncytia-inducer or macrophage-tropic, which dominate the early stages of HIV-1 infection and frequently persist during the entire course of the disease. In contrast, HIV-1 variants that use CXCR4 are typically detected at the later stages, and are associated with a rapid decline in CD4+ T cells and progression to AIDS (refs. 2,7-11). Disease progression is also associated with the emergence of concurrent infections that may affect the course of HIV disease by unknown mechanisms. A lymphotropic agent frequently reactivated in HIV-infected patients is human herpesvirus 6 (HHV-6), which has been proposed as a cofactor in AIDS progression. Here we show that in human lymphoid tissue ex vivo, HHV-6 affects HIV-1 infection in a coreceptor-dependent manner, suppressing CCR5-tropic but not CXCR4-tropic HIV-1 replication, as shown with both uncloned viral isolates and isogenic molecular chimeras. Furthermore, we demonstrate that HHV-6 increases the production of the CCR5 ligand RANTES ('regulated upon activation, normal T-cell expressed and secreted'), the most potent HIV-inhibitory CC chemokine, and that exogenous RANTES mimics the effects of HHV-6 on HIV-1, providing a mechanism for the selective blockade of CCR5-tropic HIV-1. Our data suggest that HHV-6 may profoundly influence the course of HIV-1 infection.

  10. Interleukin-3 enhances the migration of human mesenchymal stem cells by regulating expression of CXCR4.

    Science.gov (United States)

    Barhanpurkar-Naik, Amruta; Mhaske, Suhas T; Pote, Satish T; Singh, Kanupriya; Wani, Mohan R

    2017-07-14

    Mesenchymal stem cells (MSCs) represent an important source for cell therapy in regenerative medicine. MSCs have shown promising results for repair of damaged tissues in various degenerative diseases in animal models and also in human clinical trials. However, little is known about the factors that could enhance the migration and tissue-specific engraftment of exogenously infused MSCs for successful regenerative cell therapy. Previously, we have reported that interleukin-3 (IL-3) prevents bone and cartilage damage in animal models of rheumatoid arthritis and osteoarthritis. Also, IL-3 promotes the differentiation of human MSCs into functional osteoblasts and increases their in-vivo bone regenerative potential in immunocompromised mice. However, the role of IL-3 in migration of MSCs is not yet known. In the present study, we investigated the role of IL-3 in migration of human MSCs under both in-vitro and in-vivo conditions. MSCs isolated from human bone marrow, adipose and gingival tissues were used for in-vitro cell migration, motility and wound healing assays in the presence or absence of IL-3. The effect of IL-3 preconditioning on expression of chemokine receptors and integrins was examined by flow cytometry and real-time PCR. The in-vivo migration of IL-3-preconditioned MSCs was investigated using a subcutaneous matrigel-releasing stromal cell-derived factor-1 alpha (SDF-1α) model in immunocompromised mice. We observed that human MSCs isolated from all three sources express IL-3 receptor-α (IL-3Rα) both at gene and protein levels. IL-3 significantly enhances in-vitro migration, motility and wound healing abilities of MSCs. Moreover, IL-3 preconditioning upregulates expression of chemokine (C-X-C motif) receptor 4 (CXCR4) on MSCs, which leads to increased migration of cells towards SDF-1α. Furthermore, CXCR4 antagonist AMD3100 decreases the migration of IL-3-treated MSCs towards SDF-1α. Importantly, IL-3 also induces in-vivo migration of MSCs towards

  11. Expression and significance of SDF-1/CXCR4 in alkali-burned cornealtissue in mouse%碱烧伤小鼠角膜组织中SDF-1/CXCR4的表达及意义

    Institute of Scientific and Technical Information of China (English)

    彭亮红; 柳林

    2010-01-01

    目的 探讨基质细胞衍生因子-1(SDF-1)和CXCR4在小鼠角膜碱烧伤新生血管形成中的作用.方法 应用在角膜中央放置NaOH滤纸片的方法 构建C57/BL小鼠角膜碱烧伤角膜新生血管动物模型,通过免疫组织化学、RT-PCR、Western blot法检测碱烧伤后不同时间点角膜组织中SDF-1和CXCR4 mRNA及蛋白的表达情况.结果 免疫组织化学检测显示,正常小鼠角膜基质层无明显SDF-1的阳性表达,CXCR4仅在角膜上皮层呈弱阳性表达.RT-PCR检测显示,与正常对照组相比,碱烧伤后各时间点SDF-1和CXCR4 mRNA表达均明显升高(P<0.05);Western blot检测显示SDF-1和CXCR4蛋白的表达也可见相似的变化趋势(P<0.05).SDF-1和CXCR4在角膜中的表达于第7天达高峰,第14天开始下降,但仍高于正常.结论 SDF-1/CXCR4在碱烧伤后小鼠角膜组织中的表达增加,在角膜碱烧伤的炎症和新生血管的形成和发展过程中可能发挥重要作用.%Background Recent research showed that stromal cell-derived factor-1 (SDF-1) plays critical role in mediating inflammation,metastasis of tumour and neovascularization of tumour.However,There is still no report about the research of the effects of SDF-1 on alkali-burn-induced corneal neovascularization (CNV).Objective The aim of this study attempts to investigate the role of SDF-1 and chemokine receptor CXCR4 in alkali-induced corneal neovascularization in mice.Methods Alkali-induced-corneal neovascularization animal models were constructed of in 15 eyes of 15 clean C57/BL mice by placing the filter paper with 1 mol/L NaOH to the central cornea for 10 seconds.The animals were sacrificed and specimens of cornea were obtained in 3,7,14 days after alkali burn of cornea.The expression of SDF-1/CXCR4 protein in the corneal tissues was detected by immunohistochemistry and Western blot,and expression of SDF-1/CXCR4 mRNA was detected by reverse transcription PCR (RT-PCR).Results SDF-1 was absent expressed and

  12. The amino-terminal domain of the CCR2 chemokine receptor acts as coreceptor for HIV-1 infection.

    Science.gov (United States)

    Frade, J M; Llorente, M; Mellado, M; Alcamí, J; Gutiérrez-Ramos, J C; Zaballos, A; Real, G; Martínez-A, C

    1997-08-01

    The chemokines are a homologous serum protein family characterized by their ability to induce activation of integrin adhesion molecules and leukocyte migration. Chemokines interact with their receptors, which are composed of a single-chain, seven-helix, membrane-spanning protein coupled to G proteins. Two CC chemokine receptors, CCR3 and CCR5, as well as the CXCR4 chemokine receptor, have been shown necessary for infection by several HIV-1 virus isolates. We studied the effect of the chemokine monocyte chemoattractant protein 1 (MCP-1) and of a panel of MCP-1 receptor (CCR2)-specific monoclonal antibodies (mAb) on the suppression of HIV-1 replication in peripheral blood mononuclear cells. We have compelling evidence that MCP-1 has potent HIV-1 suppressive activity when HIV-1-infected peripheral blood lymphocytes are used as target cells. Furthermore, mAb specific for the MCP-1R CCR2 which recognize the third extracellular CCR2 domain inhibit all MCP-1 activity and also block MCP-1 suppressive activity. Finally, a set of mAb specific for the CCR2 amino-terminal domain, one of which mimics MCP-1 activity, has a potent suppressive effect on HIV-1 replication in M- and T-tropic HIV-1 viral isolates. We conjecture a role for CCR2 as a coreceptor for HIV-1 infection and map the HIV-1 binding site to the amino-terminal part of this receptor. This concurs with results showing that the CCR5 amino terminus is relevant in HIV-1 infection, although chimeric fusion of various extracellular domains shows that other domains are also implicated. We discuss the importance of CCR2 structure relative to its coreceptor role and the role of anti-CCR2 receptor antibodies in the prevention of HIV-1 infection.

  13. Isolation and characterization of a new chemokine receptor gene, the putative chicken CXCR1.

    Science.gov (United States)

    Li, Q J; Lu, S; Ye, R D; Martins-Green, M

    2000-10-31

    This study delineates the isolation and characterization of a novel chemokine receptor gene, the putative chicken CXC receptor 1 (cCXCR1). Using a human CXCR1 probe, we isolated several positive clones from a chicken genomic library. One of the clones contained a fragment of approximately 5000bp that hybridized strongly with the hCXCR1 probe. This fragment was sequenced and subjected to a variety of computer analyses. The open reading frame for this gene predicts a seven transmembrane domain protein with all the characteristics of a chemokine receptor and with 67% sequence homology to hCXCR1, 65% to hCXCR2 and also with considerable sequence homology to other human chemokine receptors such as hCXCR4 (50%), hCCR2 (49%) and hCCR1 (49%). However, the homology to a previously isolated potential G-protein-coupled receptor for chickens (AvCRL1) is only 47%. Using 5' RACE, two transcription initiation sites were identified suggesting the potential for the expression of two protein isoforms (I and II) in vivo. The promoter for the putative cCXCR1 contains a variety of consensus transcription factor binding elements that can potentially be involved in the expression of this chicken receptor upon stimulation by stress-inducing agents. RT-PCR analysis was used to determine the pattern of expression of the larger isoform (I) of this receptor in a variety of tissues. This form of the receptor is expressed primarily in the organs of the gastrointestinal tract, tissues that are frequently exposed to stress-inducing agents, but not in the central nervous system, tissues that are protected from insult by the blood barrier. Using the same RT-PCR approach we show that stress-inducing agents, such as 'first-hand' and 'second-hand' cigarette smoke components, tumor promoters and thrombin, differentially stimulate the expression of the isoform I in primary fibroblasts. Thrombin is an enzyme that plays many important roles in thrombosis, angiogenesis and wound healing and exposure to

  14. Innate Immunity Derived Factors as External Modulators of the CXCL12 - CXCR4 Axis and Their Role in Stem Cell Homing and Mobilization

    Directory of Open Access Journals (Sweden)

    Mariusz Z. Ratajczak, Karol Serwin, Gabriela Schneider

    2013-01-01

    Full Text Available The α-chemokine CXCL12 (stromal derived factor-1; SDF-1 and its corresponding GαI protein-coupled CXCR4 receptor axis play an important role in retention of hematopoietic stem progenitor cells (HSPCs in bone marrow (BM stem cell niches. CXCL12 has also been identified as a strong chemoattractant for HSPCs and implicated both in homing of HSPCs to BM after transplantation and in egress of these cells from BM into peripheral blood (PB. However, since CXCL12, as a peptide, is highly susceptible to degradation by proteolytic enzymes, its real biological availability in biological fluids may be somewhat limited. In this review, we will present data demonstrating that the CXCL12-CXCR4 axis is positively modulated by innate immunity-derived several external factors, ensuring that even low (near threshold doses of CXCL12 still exert a robust chemotactic influence on HSPCs.

  15. Novel guanide-substituted compounds bind to CXCR4 and inhibit breast cancer metastasis.

    Science.gov (United States)

    Shepard, Joyce B; Wilkinson, Royce A; Starkey, Jean R; Teintze, Martin

    2014-01-01

    CXCR4 has been shown to be overexpressed on breast cancer cells including the human MDA-MB-231 cell line. Cancer cells overexpressing the CXCR4 receptor are capable of undergoing metastasis to organs expressing high levels of CXCL12. We have synthesized numerous guanide, biguanide, phenylguanide, and naphthylguanide compounds that bind to CXCR4 at the CXCL12-binding site and thus should prevent CXCR4-facilitated cancer metastasis. The novel compounds presented here were tested for CXCR4 affinity, toxicity, receptor activation, and for their ability to prevent breast cancer metastases. Three of the compounds bound to CXCR4 at IC50 values of 0.06-0.2 μmol/l, with no associated cell toxicity or receptor activation at these concentrations. These high CXCR4 affinity compounds also showed inhibition of in-vitro wound migration. They were then tested in an in-vivo mouse breast cancer lung colony model. All of these compounds showed reductions in the number of MDA-MB-231 lung metastases compared with mock-treated control mice without evidence of cardiac, liver, or kidney toxicity in treated mice.

  16. Chemokines and chemokine receptors in inflammation of the nervous system

    DEFF Research Database (Denmark)

    Huang, D; Han, Yong-Chang; Rani, M R

    2000-01-01

    This article focuses on the production of chemokines by resident glial cells of the nervous system. We describe studies in two distinct categories of inflammation within the nervous system: immune-mediated inflammation as seen in experimental autoimmune encephalomyelitis (EAE) or multiple sclerosis...

  17. Genomic organization, annotation, and ligand-receptor inferences of chicken chemokines and chemokine receptor genes based on comparative genomics

    Directory of Open Access Journals (Sweden)

    Sze Sing-Hoi

    2005-03-01

    Full Text Available Abstract Background Chemokines and their receptors play important roles in host defense, organogenesis, hematopoiesis, and neuronal communication. Forty-two chemokines and 19 cognate receptors have been found in the human genome. Prior to this report, only 11 chicken chemokines and 7 receptors had been reported. The objectives of this study were to systematically identify chicken chemokines and their cognate receptor genes in the chicken genome and to annotate these genes and ligand-receptor binding by a comparative genomics approach. Results Twenty-three chemokine and 14 chemokine receptor genes were identified in the chicken genome. All of the chicken chemokines contained a conserved CC, CXC, CX3C, or XC motif, whereas all the chemokine receptors had seven conserved transmembrane helices, four extracellular domains with a conserved cysteine, and a conserved DRYLAIV sequence in the second intracellular domain. The number of coding exons in these genes and the syntenies are highly conserved between human, mouse, and chicken although the amino acid sequence homologies are generally low between mammalian and chicken chemokines. Chicken genes were named with the systematic nomenclature used in humans and mice based on phylogeny, synteny, and sequence homology. Conclusion The independent nomenclature of chicken chemokines and chemokine receptors suggests that the chicken may have ligand-receptor pairings similar to mammals. All identified chicken chemokines and their cognate receptors were identified in the chicken genome except CCR9, whose ligand was not identified in this study. The organization of these genes suggests that there were a substantial number of these genes present before divergence between aves and mammals and more gene duplications of CC, CXC, CCR, and CXCR subfamilies in mammals than in aves after the divergence.

  18. Nuclear Pattern of CXCR4 Expression Is Associated with a Better Overall Survival in Patients with Gastric Cancer

    Directory of Open Access Journals (Sweden)

    Bahram Nikkhoo

    2014-01-01

    Full Text Available Introduction. Previous studies have shown that stromal-derived factor-1 (CXCL12 and its receptor, CXCR4, play a crucial role in metastasis of various tumors. Similarly, it has been cleared that CXCR4 is expressed on the cell surface of gastric cancers. However, nuclear expression of CXCR4 and its clinical importance have not been yet studied. Materials and Methods. Herein, we studied the expression of CXCR4 in gastric samples from patients with gastric adenocarcinoma as well as human gastric carcinoma cell line, AGS, by employing RT-PCR, immunohistochemistry, and flow cytometry techniques. Results. RT-PCR data showed that CXCR4 is highly expressed on AGS cells. This was confirmed by IHC and FACS as CXCR4 was detected on cell membrane, in cytoplasm, and in nucleus of AGS cells. Moreover, we found that both cytoplasmic and nuclear CXCR4 are strongly expressed in primary gastric cancer and the cytoplasmic pattern of CXCR4 tends to be associated with a shorter overall survival than nuclear staining. In conclusion, we present evidence for the first time that both cytoplasmic and nuclear expression of CXCR4 are detectable in gastric cancer tissues. However, the role of both cytoplasmic and nuclear CXCR4 needs to be further elucidated.

  19. Physical exercise regulates neural stem cells proliferation and migration via SDF-1α/CXCR4 pathway in rats after ischemic stroke.

    Science.gov (United States)

    Luo, Jing; Hu, Xiquan; Zhang, Liying; Li, Lili; Zheng, Haiqing; Li, Menglin; Zhang, Qingjie

    2014-08-22

    Physical exercise is beneficial to functional recovery after stroke. But its underling mechanism is still unknown. It is reported that neural stem cells (NSCs) proliferation, migration and differentiation play an important role in recovery following stroke, furthermore, stromal cell derived factor-1α (SDF-1α) and its chemokine receptor type 4 (CXCR4) regulate NSCs migration. This study is aimed to examine whether physical exercise improves functional recovery by enhancing NSCs proliferation, migration and differentiation through SDF-1α/CXCR4 axis in rats after ischemic stroke. Rats that sustained transient middle cerebral artery occlusion (MCAO) were treated with physical exercise after MCAO. AMD3100 (an antagonist of CXCR4) was used to confirm the effect of SDF-1α/CXCR4 axis on exercise-mediated NSCs mobilization. We found that physical exercise improved functional recovery and reduced infarct volume. Moreover, 5-bromo-2'-deoxyuridine (BrdU), doublecortin (Dcx)-positive cells in the ipsilateral SVZ and BrdU/neuron-specific nuclear protein (NeuN)-positive cells in the ipsilateral striatum were increased by physical exercise. Simultaneously, SDF-1α-positive cells were significantly higher in physical exercise group than those in control group. Our results indicate that physical exercise improves functional recovery in ischemic rats possibly by enhancement of NSCs proliferation, migration in the SVZ and differentiation in the damaged striatum. Moreover, SDF-1α/CXCR4 pathway involves in exercise-mediated NSCs proliferation and migration but not differentiation. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  20. Chemokine receptor CCR5 in interferon-treated multiple sclerosis

    DEFF Research Database (Denmark)

    Sellebjerg, F; Kristiansen, T B; Wittenhagen, P

    2007-01-01

    To study the relationship between CC chemokine receptor CCR5 expression and disease activity in multiple sclerosis (MS) patients treated with beta-interferon (IFN-beta).......To study the relationship between CC chemokine receptor CCR5 expression and disease activity in multiple sclerosis (MS) patients treated with beta-interferon (IFN-beta)....

  1. Natural scrub typhus antibody suppresses HIV CXCR4(X4 viruses

    Directory of Open Access Journals (Sweden)

    George Watt

    2013-05-01

    Full Text Available Viral load generally rises in HIV-infected individuals with a concomitant infection, but falls markedly in some individuals with scrub typhus (ST, a common Asian rickettsial infection. ST infection appears to shift the viral population from CXCR4-using (X4 to CCR5-utilizing (R5 strains, and there is evidence of cross-reactivity between ST-specific antibodies and HIV-1. We examined the mechanism of ST suppression of HIV by measuring the effects of ST infection on X4 and R5 viruses in vivo and in vitro, and assessing the relative contributions of antibodies and chemokines to the inhibitory effect. In vivo, a single scrub typhus plasma infusion markedly reduced the subpopulation of HIV-1 viruses using the X4 co-receptor in all 8 recipients, and eliminated X4 viruses 6 patients. In vitro, the 14 ST sera tested all inhibited the replication of an X4 but not an R5 virus. This inhibitory effect was maintained if ST sera were depleted of chemokines but was lost upon removal of antibodies. Sera from ST-infected mice recognized a target that co-localized with X4 HIV gp120 in immunofluorescent experiments. These in vivo and in vitro data suggest that acute ST infection generates cross-reactive antibodies that produce potent suppression of CXCR4- but not CCR5-using HIV-1 viruses. ST suppression of HIV replication could reveal novel mechanisms that could be exploited for vaccination strategies, as well as aid in the development of fusion inhibitors and other new therapeutic regimens. This also appears to be the first instance where one pathogen is neutralized by antibody produced in response to infection by a completely unrelated organism.

  2. Natural Scrub Typhus Antibody Suppresses HIV CXCR4(X4) Viruses.

    Science.gov (United States)

    Watt, George; Kantipong, Pacharee; Burnouf, Thierry; Shikuma, Cecilia; Philpott, Sean

    2013-01-22

    Viral load generally rises in HIV-infected individuals with a concomitant infection, but falls markedly in some individuals with scrub typhus (ST), a common Asian rickettsial infection. ST infection appears to shift the viral population from CXCR4-using (X4) to CCR5-utilizing (R5) strains, and there is evidence of cross-reactivity between ST-specific antibodies and HIV-1. We examined the mechanism of ST suppression of HIV by measuring the effects of ST infection on X4 and R5 viruses in vivo and in vitro, and assessing the relative contributions of antibodies and chemokines to the inhibitory effect. In vivo, a single scrub typhus plasma infusion markedly reduced the subpopulation of HIV-1 viruses using the X4 co-receptor in all 8 recipients, and eliminated X4 viruses 6 patients. In vitro, the 14 ST sera tested all inhibited the replication of an X4 but not an R5 virus. This inhibitory effect was maintained if ST sera were depleted of chemokines but was lost upon removal of antibodies. Sera from STinfected mice recognized a target that co-localized with X4 HIV gp120 in immunofluorescent experiments. These in vivo and in vitro data suggest that acute ST infection generates cross-reactive antibodies that produce potent suppression of CXCR4- but not CCR5-using HIV-1 viruses. ST suppression of HIV replication could reveal novel mechanisms that could be exploited for vaccination strategies, as well as aid in the development of fusion inhibitors and other new therapeutic regimens. This also appears to be the first instance where one pathogen is neutralized by antibody produced in response to infection by a completely unrelated organism.

  3. Recruitment of exogenous mesenchymal stem cells in mandibular distraction osteogenesis by the stromal cell-derived factor-1/chemokine receptor-4 pathway in rats.

    Science.gov (United States)

    Cao, Jian; Wang, Lei; Du, Zhao-jie; Liu, Peng; Zhang, Ya-bo; Sui, Jian-fu; Liu, Yan-pu; Lei, De-lin

    2013-12-01

    Distraction osteogenesis is widely used in orthopaedic and craniofacial surgery. However, its exact mechanism is still poorly understood. The purpose of this study was to find out whether there is systemic recruitment of mesenchymal stem cells (MSC) to the neocallus in the distraction gap by the stromal cell-derived factor-1 (SDF-1)/CXC chemokine receptor 4 (CXCR4) axis during osteogenesis. We examined the migration of MSC towards a gradient of SDF-1 in vitro. We also transplanted MSC labelled with green fluorescent protein (GFP) intravenously, with or without treatment with CXCR4-blocking antibody, into rats that had had unilateral mandibular distraction osteogenesis, and investigated the distribution of cells labelled with GFP in the soft callus after 24 h. We found that SDF-1 facilitated the migration potency of MSC both in vitro and in vivo, and this migration could be inhibited by AMD3100, an antagonist of CXCR4, and promoted by local infusion of exogenous SDF-1 into the distraction gap. This study provides a new insight into the molecular basis of how new bone is regenerated during distraction osteogenesis.

  4. Drug discovery and chemokine receptor antagonists: eppur si muove!

    Science.gov (United States)

    Terricabras, Emma; Benjamim, Claudia; Godessart, Nuria

    2004-11-01

    The blockade of leukocyte migration has been demonstrated to be a valid option for the treatment of several autoimmune diseases. Chemokines play an active role in regulating cell infiltration into inflammatory sites and disrupting chemokine-receptor interactions has emerged as an alternative therapeutic approach. Pharmaceutical companies have developed an intense activity in the drug discovery of chemokine receptor antagonists in the last 10 years. Potent and selective compounds have been obtained and some of them are currently being evaluated in the clinic. The success of these trials will demonstrate whether the blockade of a single receptor is of therapeutic benefit. Alternative approaches, such as pan-receptor antagonists or inhibitors of the signalling pathways evoked by chemokines, are also being explored. In the meantime, new relationships between chemokines and receptors will be revealed, increasing our knowledge of such a fascinating field.

  5. Chemokines and chemokine receptors as promoters of prostate cancer growth and progression.

    Science.gov (United States)

    Salazar, Nicole; Castellan, Miguel; Shirodkar, Samir S; Lokeshwar, Bal L

    2013-01-01

    Prostate cancer (CaP) is estimated to be first in incidence among cancers, with more than 240,000 new cases in 2012 in the United States. Chemokines and their receptors provide survival, proliferation, and invasion characteristics to CaP cells in both primary sites of cancer and metastatic locations. The emerging data demonstrate that many chemokines and their receptors are involved in the multistep process of CaP, leading to metastasis, and, further, that these factors act cooperatively to enhance other mechanisms of tumor cell survival, growth, and metastasis. Changes of chemokine receptor cohorts may be necessary to activate tumor-promoting signals. Chemokine receptors can activate downstream effectors, such as mitogen-activated protein kinases, by complex mechanisms of ligand-dependent activation of cryptic growth factors; guanosine triphosphate-binding, protein-coupled activation of survival kinases; or transactivation of other receptors such as ErbB family members. We describe vanguard research in which more than the classic view of chemokine receptor biology was clarified. Control of chemokines and inhibition of their receptor activation may add critical tools to reduce tumor growth, especially in chemo-hormonal refractory CaP that is both currently incurable and the most aggressive form of the disease, accounting for most of the more than 28,000 annual deaths.

  6. Chemokine and chemokine receptors in autoimmunity: the case of primary biliary cholangitis.

    Science.gov (United States)

    Choi, Jinjung; Selmi, Carlo; Leung, Patrick S C; Kenny, Thomas P; Roskams, Tania; Gershwin, M Eric

    2016-06-01

    Chemokines represent a major mediator of innate immunity and play a key role in the selective recruitment of cells during localized inflammatory responses. Beyond critical extracellular mediators of leukocyte trafficking, chemokines and their cognate receptors are expressed by a variety of resident and infiltrating cells (monocytes, lymphocytes, NK cells, mast cells, and NKT cells). Chemokines represent ideal candidates for mechanistic studies (particularly in murine models) to better understand the pathogenesis of chronic inflammation and possibly become biomarkers of disease. Nonetheless, therapeutic approaches targeting chemokines have led to unsatisfactory results in rheumatoid arthritis, while biologics against pro-inflammatory cytokines are being used worldwide with success. In this comprehensive review we will discuss the evidence supporting the involvement of chemokines and their specific receptors in mediating the effector cell response, utilizing the autoimmune/primary biliary cholangitis setting as a paradigm.

  7. Topotecan inhibits cancer cell migration by down-regulation of chemokine CC motif receptor 7 and matrix metalloproteinases

    Institute of Scientific and Technical Information of China (English)

    Sen-sen LIN; Li SUN; Yan-kai ZHANG; Ren-ping ZHAO; Wen-lu LIANG; Sheng-tao YUAN; Lu-yong ZHANG

    2009-01-01

    Aim: The aim of this study was to investigate the effect of topotecan (TPT) on cancer cell migration.Methods: Growth inhibition of TPT was analyzed by MTT assay, and cancer cell migration was measured by transwell double chamber assay. To verify the effect of TPT on the chemokine receptors CXCR4 and CCR7, quantitative PCR, semi-quantitative PCR and Western blot analysis were performed. The secretion of MMP-2 and MMP-9 was detected by enzyme-linked immunosorbent assay (ELISA) and gelatin zymography. To evaluate possible contributions of CCR7 to MMP secretion, the overexpression vectors pcDNA3.1+-CCR7 and CCR7 siRNA were transiently transfected into MDA-MB-435 cells.Results: TPT inhibited cancer cell migration in a dose-dependent manner. Additionally, TPT significantly decreased the expression of CCR7 in both MDA-MB-435 and MDA-MB-231 cells and moderately reduced the expression of CXCR4 in MDA-MB-435 cells. The secretion of MMPs (MMP-2, MMP-9) was also inhibited by TPT. Overexpression of CCR7 increased the secretion of MMP-2/9 and cancer cell migration, whereas knockdown of CCR7 reduced active MMP-2/9 production and migration of MDA-MB-435 cells.Conclusion: TPT inhibited cancer cell migration by down-regulation of CCR7 and MMPs (MMP-2 and MMP-9).

  8. Enhanced Chronic Pain Management Utilizing Chemokine Receptor Antagonists

    Science.gov (United States)

    2016-08-01

    swelling and pain determined, along with initial experiments on the chemokine receptor antagonist (CRA) AMD3100. Methods were established for measuring a...Presentations………………………….22 7. Inventions , Patents and Licenses……………………..………….22 8. Reportable Outcomes……………………………………………….22 9. Other Achievements...Chemokines; Chemokine receptor antagonists; Opioid analgesics; Animal models of pain; Chemokine and cytokine measurements 3. OVERALL PROJECT

  9. Role of CXCR4-mediated bone marrow colonization in CNS infiltration by T cell acute lymphoblastic leukemia.

    Science.gov (United States)

    Jost, Tanja Rezzonico; Borga, Chiara; Radaelli, Enrico; Romagnani, Andrea; Perruzza, Lisa; Omodho, Lorna; Cazzaniga, Giovanni; Biondi, Andrea; Indraccolo, Stefano; Thelen, Marcus; Te Kronnie, Geertruy; Grassi, Fabio

    2016-06-01

    Infiltration of the central nervous system is a severe trait of T cell acute lymphoblastic leukemia. Inhibition of CXC chemokine receptor 4 significantly ameliorates T cell acute lymphoblastic leukemia in murine models of the disease; however, signaling by CXC chemokine receptor 4 is important in limiting the divagation of peripheral blood mononuclear cells out of the perivascular space into the central nervous system parenchyma. Therefore, Inhibition of CXC chemokine receptor 4 potentially may untangle T cell acute lymphoblastic leukemia cells from retention outside the brain. Here, we show that leukemic lymphoblasts massively infiltrate cranial bone marrow, with diffusion to the meninges without invasion of the brain parenchyma, in mice that underwent xenotransplantation with human T cell acute lymphoblastic leukemia cells or that developed leukemia from transformed hematopoietic progenitors. We tested the hypothesis that T cell acute lymphoblastic leukemia neuropathology results from meningeal infiltration through CXC chemokine receptor 4-mediated bone marrow colonization. Inhibition of leukemia engraftment in the bone marrow by pharmacologic CXC chemokine receptor 4 antagonism significantly ameliorated neuropathologic aspects of the disease. Genetic deletion of CXCR4 in murine hematopoietic progenitors abrogated leukemogenesis induced by constitutively active Notch1, whereas lack of CCR6 and CCR7, which have been shown to be involved in T cell and leukemia extravasation into the central nervous system, respectively, did not influence T cell acute lymphoblastic leukemia development. We hypothesize that lymphoblastic meningeal infiltration as a result of bone marrow colonization is responsible for the degenerative alterations of the neuroparenchyma as well as the alteration of cerebrospinal fluid drainage in T cell acute lymphoblastic leukemia xenografts. Therefore, CXC chemokine receptor 4 may constitute a pharmacologic target for T cell acute lymphoblastic

  10. Vascular CXCR4 expression - a novel antiangiogenic target in gastric cancer?

    Directory of Open Access Journals (Sweden)

    Barbara Ingold

    Full Text Available BACKGROUND: G-protein-coupled receptors (GPCRs are prime candidates for novel cancer prevention and treatment strategies. We searched for differentially expressed GPCRs in node positive gastric carcinomas. METHODOLOGY/PRINCIPAL FINDINGS: Differential expression of GPCRs in three node positive vs. three node negative intestinal type gastric carcinomas was analyzed by gene array technology. The candidate genes CXCL12 and its receptor CXCR4 were validated by real-time reverse-transcription polymerase chain reaction in an independent set of 37 gastric carcinomas. Translation was studied by immunohistochemistry in 347 gastric carcinomas using tissue microarrays as well as in 61 matching lymph node metastases. Protein expression was correlated with clinicopathological patient characteristics and survival. 52 GPCRs and GPCR-related genes were up- or down-regulated in node positive gastric cancer, including CXCL12. Differential expression of CXCL12 was confirmed by RT-PCR and correlated with local tumour growth. CXCL12 immunopositivity was negatively associated with distant metastases and tumour grade. Only 17% of gastric carcinomas showed CXCR4 immunopositive tumour cells, which was associated with higher local tumour extent. 29% of gastric carcinomas showed CXCR4 positive tumour microvessels. Vascular CXCR4 expression was significantly associated with higher local tumour extent as well as higher UICC-stages. When expressing both, CXCL12 in tumour cells and CXCR4 in tumour microvessels, these tumours also were highly significantly associated with higher T- and UICC-stages. Three lymph node metastases revealed vascular CXCR4 expression while tumour cells completely lacked CXCR4 in all cases. The expression of CXCL12 and CXCR4 had no impact on patient survival. CONCLUSIONS/SIGNIFICANCE: Our results substantiate the significance of GPCRs on the biology of gastric carcinomas and provide evidence that the CXCL12-CXCR4 pathway might be a novel promising

  11. Chemokines and Chemokine Receptors: Their Manifold Roles in Homeostasis and Disease

    Institute of Scientific and Technical Information of China (English)

    Yingying Le; Ye Zhou; Pablo Iribarren; Ji Ming Wang

    2004-01-01

    Chemokines are a superfamily of small proteins that bind to G protein-coupled receptors on target cells and were originally discovered as mediators of directional migration of immune cells to sites of inflammation and injury. In recent years, it has become clear that the function of chemokines extends well beyond the role in leukocyte chemotaxis. They participate in organ development, angiogenesis/angiostasis, leukocyte trafficking and homing, tumorigenesis and metastasis, as well as in immune responses to microbial infection. Therefore,chemokines and their receptors are important targets for modulation of host responses in pathophysiological conditions and for therapeutic intervention of human diseases.

  12. MicroRNA-126 inhibits colon cancer cell proliferation and invasion by targeting the chemokine (C-X-C motif) receptor 4 and Ras homolog gene family, member A, signaling pathway.

    Science.gov (United States)

    Yuan, Wei; Guo, Ye-Qing; Li, Xia-Yu; Deng, Min-Zi; Shen, Zhao-Hua; Bo, Chi-Bin; Dai, Ya-Fei; Huang, Ming-Yu; Yang, Zhen-Yu; Quan, Yong-Sheng; Tian, Li; Wang, Xiaoyan

    2016-09-13

    MicroRNA-126 (miR-126) suppresses the migration, proliferation and invasion of colon cancer cells. However, the underlying mechanisms of miR-126 in colon cancer have not been fully elucidated. In this study, in vivo experiments revealed that miR-126 inhibits colon cancer growth and metastasis. Furthermore, miR-126 was down-regulated in human colon cancer tissue, and its expression was inversely correlated with TNM stage and metastasis of patients. Low level of miR-126 identified patients with poor prognosis. And we found that miR-126 expression was negatively correlated with the expression levels of chemokine (C-X-C motif) receptor 4 (CXCR4) and components of signaling pathway of Ras homolog gene family, member A (RhoA) in vitro and in vivo. Moreover, we verified that miR-126 negatively regulated CXCR4 and RhoA signaling in vitro. In addition, either in miR-126-overexpressing or in miR- 126-silenced colon cancer cells, the restoration of CXCR4 could significantly reverse the proliferation and invasion, as well as abolish the effects of miR-126 on RhoA signaling pathway. Collectively, these results demonstrated that miR-126 acts as a tumor suppressor by inactivating RhoA signaling via CXCR4 in colon cancer. And miR-126 may serve as a prognostic marker for monitoring and treating colon cancer.

  13. Chemokine (C-X-C Ligand 12 Facilitates Trafficking of Donor Spermatogonial Stem Cells

    Directory of Open Access Journals (Sweden)

    Zhiyv Niu

    2016-01-01

    Full Text Available The chemokine (C-X-C receptor type 4 (CXCR4 is an early marker of primordial germ cells (PGCs essential for their migration and colonization of the gonads. In spermatogonial stem cells (SSCs, the expression of CXCR4 is promoted by the self-renewal factor, glial cell line-derived neurotrophic factor (GDNF. Here, we demonstrate an important role of CXCR4 during donor mouse SSCs reoccupation of the endogenous niche in recipient testis. Silencing of CXCR4 expression in mouse SSCs dramatically reduced the number of donor stem cell-derived colonies, whereas colony morphology and spermatogenesis were comparable to controls. Inhibition of CXCR4 signaling using a small molecule inhibitor (AMD3100 during the critical window of homing also significantly lowered the efficiency of donor-derived SSCs to establish spermatogenic colonies in recipient mice; however, the self-renewal of SSCs was not affected by exposure to AMD3100. Rather, in vitro migration assays demonstrate the influence of CXCR4-CXCL12 signaling in promoting germ cell migration. Together, these studies suggest that CXCR4-CXCL12 signaling functions to promote homing of SSCs towards the stem cell niche and plays a critical role in reestablishing spermatogenesis.

  14. Chemokines and their receptors in central nervous system disease.

    Science.gov (United States)

    Biber, Knut; de Jong, Eiko K; van Weering, Hilmar R J; Boddeke, Hendrikus W G M

    2006-01-01

    Almost a decade ago, it was discovered that the human deficiency virus (HIV) makes use of chemokine receptors to infect blood cells. This appreciation of the clinical relevance of specific chemokine receptors has initiated a considerable boost in the field of chemokine research. It is clear today that chemokine signaling orchestrates the immune system and is widely involved in both physiological and pathophysiological processes. Since the chemokine system offers various targets through which pathology could be influenced, most pharmaceutical companies have chosen this system as a therapeutic target for a variety of diseases. Here recent developments concerning the role of chemokines in diseases of the central nervous system (CNS) as well as their possible therapeutic relevance are discussed.

  15. Mobilization of human CD34+ CD133+ and CD34+ CD133(-) stem cells in vivo by consumption of an extract from Aphanizomenon flos-aquae--related to modulation of CXCR4 expression by an L-selectin ligand?

    Science.gov (United States)

    Jensen, Gitte S; Hart, Aaron N; Zaske, Lue A M; Drapeau, Christian; Gupta, Niraj; Schaeffer, David J; Cruickshank, J Alex

    2007-01-01

    The goal of this study was to evaluate effects on human stem cells in vitro and in vivo of an extract from the edible cyanobacterium Aphanizomenon flos-aquae (AFA) enriched for a novel ligand for human CD62L (L-selectin). Ligands for CD62L provide a mechanism for stem cell mobilization in conjunction with down-regulation of the CXCR4 chemokine receptor for stromal derived factor 1. Affinity immunoprecipitation was used to identify a novel ligand for CD62L from a water extract from AFA. The effects of AFA water extract on CD62L binding and CXCR4 expression was tested in vitro using human bone marrow CD34+ cells and the two progenitor cell lines, KG1a and K562. A double-blind randomized crossover study involving 12 healthy subjects evaluated the effects of consumption on stem cell mobilization in vivo. An AFA extract rich in the CD62L ligand reduced the fucoidan-mediated externalization of the CXCR4 chemokine receptor on bone marrow CD34+ cells by 30% and the CD62L+ CD34+ cell line KG1A by 50% but did not alter the CXCR4 expression levels on the CD34(-) cell line K562. A transient, 18% increase in numbers of circulating CD34+ stem cells maximized 1 hour after consumption (P<.0003). When 3 noncompliant volunteers were removed from analysis, the increase in CD34+ cells was 25% (P<.0001). AFA water extract contains a novel ligand for CD62L. It modulates CXCR4 expression on CD34+ bone marrow cells in vitro and triggers the mobilization of CD34+ CD133+ and CD34+ CD133(-) cells in vivo.

  16. CXC chemokine receptor 4 expression and stromal cell-derived factor-1alpha-induced chemotaxis in CD4+ T lymphocytes are regulated by interleukin-4 and interleukin-10

    DEFF Research Database (Denmark)

    Jinquan, T; Quan, S; Jacobi, H H

    2000-01-01

    We report that interleukin (IL)-4 and IL-10 can significantly up- or down-regulate CXC chemokine receptor 4 (CXCR4) expression on CD4+ T lymphocytes, respectively. Stromal cell-derived factor-1alpha (SDF-1alpha)-induced CD4+ T-lymphocyte chemotaxis was also correspondingly regulated by IL-4 and IL......,000 SDF-1alpha-binding sites per cell, among freshly isolated CD4+ T lymphocytes, and two types of CXCR4 with different affinities (Kd1 approximately 4.4 nM and Kd2 approximately 14.6 nM), and a total of approximately 130,000 SDF-1alpha-binding sites per cell, among IL-4-stimulated CD4+ T lymphocytes......-mobilization stimulation. These results indicate that the effects of IL-4 and IL-10 on the CXCR4-SDF-1 receptor-ligand pair may be of particular importance in the cytokine/chemokine environment concerning the inflammatory processes and in the progression of human immunodeficiency virus (HIV) infection....

  17. The role of chemokines and chemokine receptors in eosinophil activation during inflammatory allergic reactions

    Directory of Open Access Journals (Sweden)

    Oliveira S.H.P.

    2003-01-01

    Full Text Available Chemokines are important chemotactic cytokines that play a fundamental role in the trafficking of leukocytes to sites of inflammation. They are also potent cell-activating factors, inducing cytokine and histamine release and free radical production, a fact that makes them particularly important in the pathogenesis of allergic inflammation. The action of chemokines is regulated at the level of agonist production and processing as well as at the level of receptor expression and coupling. Therefore, an analysis of the ligands must necessarily consider receptors. Eosinophils are target cells involved in the allergic inflammatory response since they are able to release a wide variety of mediators including CC and CXC chemokines and express their receptors. These mediators could damage the airway epithelial cells and might be important to stimulate other cells inducing an amplification of the allergic response. This review focuses on recently emerging data pertaining to the importance of chemokines and chemokine receptors in promoting eosinophil activation and migration during the allergic inflammatory process. The analysis of the function of eosinophils and their chemokine receptors during allergic inflammation might be a good approach to understanding the determinants of asthma severity and to developing novel therapies.

  18. Emerging Concepts and Approaches for Chemokine-Receptor Drug Discovery

    Science.gov (United States)

    O’Hayre, Morgan; Salanga, Catherina L.; Handel, Tracy M.; Hamel, Damon J.

    2010-01-01

    Importance of the field Chemokine receptors are G protein-coupled receptors (GPCRs) most noted for their role in cell migration. However, inappropriate utilization or regulation of these receptors is implicated in many inflammatory diseases, cancer and HIV, making them important drug targets. Areas covered in this review Allostery, oligomerization, and ligand bias are presented as they pertain to chemokine receptors and their associated pathologies. Specific examples of each are described from the recent literature and their implications are discussed in terms of drug discovery efforts targeting chemokine receptors. What the reader will gain Insight into the expanding view of the multitude of pharmacological variables that need to be considered or that may be exploited in chemokine receptor drug discovery. Take home message Since 2007, two drugs targeting chemokine receptors have been approved by the FDA, Maraviroc for preventing HIV infection and Mozobil™ for hematopoietic stem cell mobilization. While these successes permit optimism for chemokine receptors as drug targets, only recently has the complexity of this system begun to be appreciated. The concepts of allosteric inhibitors, biased ligands and functional selectivity raise the possibility that drugs with precisely-defined properties can be developed. Other complexities such as receptor oligomerization and tissue-specific functional states of receptors also offer opportunities for increased target and response specificity, although it will be more challenging to translate these ideas into approved therapeutics compared to traditional approaches. PMID:21132095

  19. Toxoplasma gondii is dependent on glutamine and alters migratory profile of infected host bone marrow derived immune cells through SNAT2 and CXCR4 pathways.

    Directory of Open Access Journals (Sweden)

    I-Ping Lee

    Full Text Available The obligate intracellular parasite, Toxoplasma gondii, disseminates through its host inside infected immune cells. We hypothesize that parasite nutrient requirements lead to manipulation of migratory properties of the immune cell. We demonstrate that 1 T. gondii relies on glutamine for optimal infection, replication and viability, and 2 T. gondii-infected bone marrow-derived dendritic cells (DCs display both "hypermotility" and "enhanced migration" to an elevated glutamine gradient in vitro. We show that glutamine uptake by the sodium-dependent neutral amino acid transporter 2 (SNAT2 is required for this enhanced migration. SNAT2 transport of glutamine is also a significant factor in the induction of migration by the small cytokine stromal cell-derived factor-1 (SDF-1 in uninfected DCs. Blocking both SNAT2 and C-X-C chemokine receptor 4 (CXCR4; the unique receptor for SDF-1 blocks hypermotility and the enhanced migration in T. gondii-infected DCs. Changes in host cell protein expression following T. gondii infection may explain the altered migratory phenotype; we observed an increase of CD80 and unchanged protein level of CXCR4 in both T. gondii-infected and lipopolysaccharide (LPS-stimulated DCs. However, unlike activated DCs, SNAT2 expression in the cytosol of infected cells was also unchanged. Thus, our results suggest an important role of glutamine transport via SNAT2 in immune cell migration and a possible interaction between SNAT2 and CXCR4, by which T. gondii manipulates host cell motility.

  20. Chemokines and chemokine receptors in HIV infection: Role in pathogenesis and therapeutics

    Directory of Open Access Journals (Sweden)

    Suresh P

    2006-01-01

    Full Text Available Chemokines are known to function as regulatory molecules in leukocyte maturation, traffic, homing of lymphocytes and in the development of lymphoid tissues. Besides these functions in the immune system, certain chemokines and their receptors are involved in HIV pathogenesis. In order to infect a target cell, the HIV envelope glycoprotein gp120 has to interact with the cellular receptor CD-4 and co-receptor, CC or CXC chemokine receptors. Genetic findings have yielded major insights into the in vivo roles of individual co-receptors and their ligands in providing resistance to HIV infection. Mutations in chemokine receptor genes are associated with protection against HIV infections and also involved in delayed progression to AIDS in infected individuals. Blocking of chemokine receptors interrupts HIV infection in vitro and this offers new options for therapeutic strategies. Approaches have been made to study the CCR-5 inhibitors as antiviral therapies and possibly as components of a topical microbicide to prevent HIV-1 sexual transmission. Immune strategies aimed at generating anti-CCR-5 antibodies at the level of the genital mucosa might be feasible and represent a strategy to induce mucosal HIV- protective immunity. It also remains to be seen how these types of agents will act in synergy with existing HIV-1 targeted anti viral, or those currently in developments. Beyond providing new perspectives in fundamental aspects of the HIV-1 transmission and pathogenesis, chemokines and their receptors suggest new areas for developing novel therapeutic and preventive strategies against HIV infections. Studies in this review were identified through a search for relevant literature in the pubmed database of the national library of medicine. In this review, some developments in chemokine research with particular focus on their roles in HIV pathogenesis, resistance and therapeutic applications have been discussed.

  1. The novel CXCL12gamma isoform encodes an unstructured cationic domain which regulates bioactivity and interaction with both glycosaminoglycans and CXCR4.

    Directory of Open Access Journals (Sweden)

    Cédric Laguri

    Full Text Available BACKGROUND: CXCL12alpha, a chemokine that importantly promotes the oriented cell migration and tissue homing of many cell types, regulates key homeostatic functions and pathological processes through interactions with its cognate receptor (CXCR4 and heparan sulfate (HS. The alternative splicing of the cxcl12 gene generates a recently identified isoform, CXCL12gamma, which structure/function relationships remain unexplored. The high occurrence of basic residues that characterize this isoform suggests however that it could feature specific regulation by HS. METHODOLOGY/PRINCIPAL FINDINGS: Using surface plasmon resonance and NMR spectroscopy, as well as chemically and recombinantly produced chemokines, we show here that CXCL12gamma first 68 amino acids adopt a structure closely related to the well described alpha isoform, followed by an unfolded C-terminal extension of 30 amino acids. Remarkably, 60% of these residues are either lysine or arginine, and most of them are clustered in typical HS binding sites. This provides the chemokine with the highest affinity for HP ever observed (Kd = 0.9 nM, and ensures a strong retention of the chemokine at the cell surface. This was due to the unique combination of two cooperative binding sites, one strictly required, found in the structured domain of the protein, the other one being the C-terminus which essentially functions by enhancing the half life of the complexes. Importantly, this peculiar C-terminus also regulates the balance between HS and CXCR4 binding, and consequently the biological activity of the chemokine. CONCLUSIONS/SIGNIFICANCE: Together these data describe an unusual binding process that gives rise to an unprecedented high affinity between a chemokine and HS. This shows that the gamma isoform of CXCL12, which features unique structural and functional properties, is optimized to ensure its strong retention at the cell surface. Thus, depending on the chemokine isoform to which it binds, HS

  2. New G-protein-coupled receptor structures provide insights into the recognition of CXCL12 and HIV-1 gp120 by CXCR4

    Institute of Scientific and Technical Information of China (English)

    Chen Zhong; Jianping Ding

    2011-01-01

    The G protein-coupled receptor (GPCR) superfamily consists of thousands of integral membrane proteins that exert a wide variety of physiological functions and account for a large portion of the drag targets identified so far.However,structural knowledge of GPCRs is scarce, with crystal structures determined for only a few members including β1and β2 adrenergic receptors, adenosine receptor, rhodopsin,and dopamine D3 receptor [1].

  3. Chemotherapy induces adaptive drug resistance and metastatic potentials via phenotypic CXCR4-expressing cell state transition in ovarian cancer

    Science.gov (United States)

    Lee, Hyun Hee; Bellat, Vanessa

    2017-01-01

    Ovarian cancer (OVC) patients who receive chemotherapy often acquire drug resistance within one year. This can lead to tumor reoccurrence and metastasis, the major causes of mortality. We report a transient increase of a small distinctive CXCR4High/CD24Low cancer stem cell population (CXCR4High) in A2780 and SKOV-3 OVC cell lines in response to cisplatin, doxorubicin, and paclitaxel, treatments. The withdrawal of the drug challenges reversed this cell-state transition. CXCR4High exhibits dormancy in drug resistance and mesenchymal-like invasion, migration, colonization, and tumor formation properties. The removal of this cell population from a doxorubicin-resistant A2780 lineage (A2780/ADR) recovered the sensitivity to drug treatments. A cytotoxic peptide (CXCR4-KLA) that can selectively target cell-surface CXCR4 receptor was further synthesized to investigate the therapeutic merits of targeting CXCR4High. This peptide was more potent than the conventional CXCR4 antagonists (AMD3100 and CTCE-9908) in eradicating the cancer stem cells. When used together with cytotoxic agents such as doxorubicin and cisplatin, the combined drug-peptide regimens exhibited a synergistic cell-killing effect on A2780, A2780/ADR, and SKOV-3. Our data suggested that chemotherapy could establish drug-resistant and tumor-initiating properties of OVC via reversible CXCR4 cell state transition. Therapeutic strategies designed to eradicate rather than antagonize CXCR4High might offer a far-reaching potential as supportive chemotherapy. PMID:28196146

  4. Tyrosylprotein sulfotransferase-1 and tyrosine sulfation of chemokine receptor 4 are induced by Epstein-Barr virus encoded latent membrane protein 1 and associated with the metastatic potential of human nasopharyngeal carcinoma.

    Directory of Open Access Journals (Sweden)

    Juan Xu

    Full Text Available The latent membrane protein 1 (LMP1, which is encoded by the Epstein-Barr virus (EBV, is an important oncogenic protein that is closely related to carcinogenesis and metastasis of nasopharyngeal carcinoma (NPC, a prevalent cancer in China. We previously reported that the expression of the functional chemokine receptor CXCR4 is associated with human NPC metastasis. In this study, we show that LMP1 induces tyrosine sulfation of CXCR4 through tyrosylprotein sulfotransferase-1 (TPST-1, an enzyme that is responsible for catalysis of tyrosine sulfation in vivo, which is likely to contribute to the highly metastatic character of NPC. LMP1 could induce tyrosine sulfation of CXCR4 and its associated cell motility and invasiveness in a NPC cell culture model. In contrast, the expression of TPST-1 small interfering RNA reversed LMP1-induced tyrosine sulfation of CXCR4. LMP1 conveys signals through the epidermal growth factor receptor (EGFR pathway, and EGFR-targeted siRNA inhibited the induction of TPST-1 by LMP1. We used a ChIP assay to show that EGFR could bind to the TPST-1 promoter in vivo under the control of LMP1. A reporter gene assay indicated that the activity of the TPST-1 promoter could be suppressed by deleting the binding site between EGFR and TPST-1. Finally, in human NPC tissues, the expression of TPST-1 and LMP1 was directly correlated and clinically, the expression of TPST-1 was associated with metastasis. These results suggest the up-regulation of TPST-1 and tyrosine sulfation of CXCR4 by LMP1 might be a potential mechanism contributing to NPC metastasis.

  5. Chemokines and chemokine receptors expression in the lesions of patients with American cutaneous leishmaniasis

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    Nilka Luisa Diaz

    2013-06-01

    Full Text Available American cutaneous leishmaniasis (ACL presents distinct active clinical forms with different grades of severity, known as localised (LCL, intermediate (ICL and diffuse (DCL cutaneous leishmaniasis. LCL and DCL are associated with a polarised T-helper (Th1 and Th2 immune response, respectively, whereas ICL, or chronic cutaneous leishmaniasis, is associated with an exacerbated immune response and a mixed cytokine expression profile. Chemokines and chemokine receptors are involved in cellular migration and are critical in the inflammatory response. Therefore, we evaluated the expression of the chemokines CXCL10, CCL4, CCL8, CCL11 and CXCL8 and the chemokine receptors CCR3, CXCR3, CCR5 and CCR7 in the lesions of patients with different clinical forms of ACL using immunohistochemistry. LCL patients exhibited a high density of CXCL10+, CCL4+ and CCL8+ cells, indicating an important role for these chemokines in the local Th1 immune response and the migration of CXCR3+ cells. LCL patients showed a higher density of CCR7+ cells than ICL or DCL patients, suggesting major dendritic cell (DC migration to lymph nodes. Furthermore, DCL was associated with low expression levels of Th1-associated chemokines and CCL11+ epidermal DCs, which contribute to the recruitment of CCR3+ cells. Our findings also suggest an important role for epidermal cells in the induction of skin immune responses through the production of chemokines, such as CXCL10, by keratinocytes.

  6. Biased and G protein-independent signaling of chemokine receptors

    Directory of Open Access Journals (Sweden)

    Anne eSteen

    2014-06-01

    Full Text Available Biased signaling or functional selectivity occurs when a 7TM receptor preferentially activates one of several available pathways. It can be divided into three distinct forms: ligand bias, receptor bias, and tissue or cell bias, where it is mediated by different ligands (on the same receptor, different receptors (with the same ligand or different tissues or cells (for the same ligand-receptor pair. Most often biased signaling is differentiated into G protein-dependent and β-arrestin-dependent signaling. Yet, it may also cover signaling differences within these groups. Moreover, it may not be absolute, i.e. full versus no activation. Here we discuss biased signaling in the chemokine system, including the structural basis for biased signaling in chemokine receptors, as well as in class A 7TM receptors in general. This includes overall helical movements and the contributions of micro-switches based on recently published 7TM crystals and molecular dynamics studies. All three forms of biased signaling are abundant in the chemokine system. This challenges our understanding of classic redundancy inevitably ascribed to this system, where multiple chemokines bind to the same receptor and where a single chemokine may bind to several receptors – in both cases with the same functional outcome. The ubiquitous biased signaling confer a hitherto unknown specificity to the chemokine system with a complex interaction pattern that is better described as promiscuous with context-defined roles and different functional outcomes in a ligand-, receptor- or cell/tissue-defined manner. As the low number of successful drug development plans implies, there are great difficulties in targeting chemokine receptors; in particular with regard to receptor antagonists as anti-inflammatory drugs. Un-defined and putative non-selective targeting of the complete cellular signaling system could be the underlying cause of lack of success. Therefore, biased ligands could be the

  7. Genetic variants in the chemokines and chemokine receptors in Chagas disease.

    Science.gov (United States)

    Flórez, Oscar; Martín, Javier; González, Clara Isabel

    2012-08-01

    Clinical symptoms of Chagas' disease occur in 30% of the individuals infected with Trypanosoma cruzi and are characterised by heart inflammation and dysfunction. Chemokines and chemokine receptors control the migration of leukocytes during the inflammatory process and are involved in the modulation of Th1 or Th2 responses. To determine their influence, we investigated the possible role of CCL5/RANTES and CXCL8/IL8 chemokines, and CCR2 and CCR5 chemokines receptors cluster gene polymorphisms with the development of chagasic cardiomyopathy. Our study included 260 Chagas seropositive individuals (asymptomatic, n=130; cardiomyopathic, n=130) from an endemic area of Colombia. Genotyping was performed by polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) and TaqMan SNP genotyping assay. We found statistically significant differences in the distribution of the CCR5 human haplogroup (HH)-A (p=0.027; OR=3.78, 95% CI=1.04-13.72). Moreover, we found that the CCR5-2733 G and CCR5-2554 T alleles are associated, respectively, with a reduced risk of susceptibility and severity to develop chagasic cardiomyopathy. No other associations were found to be significant for the other polymorphisms analysed in the CCR5, CCR2, CCL5/RANTES and CXCL8/IL8 genes. Our data suggest that the analysed chemokines and chemokine receptor genetic variants have a weak but important association with the development of chagasic cardiomyopathy in the population under study.

  8. Regulated expression of CXCR4 constitutive active mutants revealed the up-modulated chemotaxis and up-regulation of genes crucial for CXCR4 mediated homing and engraftment of hematopoietic stem/progenitor cells

    Directory of Open Access Journals (Sweden)

    Sharma M

    2013-04-01

    Full Text Available SDF-1/CXCR4 axis plays a principle role in the homing and engraftment of hematopoietic stem/progenitor cells (HSPCs, a process that defines cells ability to reach and seed recipient bone marrow niche following their intravenous infusion. However, the proper functioning of CXCR4 downstream signaling depends upon consistent optimal expression of both SDF-1 ligand and its receptor CXCR4, which in turn is variable and regulated by several factors. The constitutive active mutants of CXCR4 (N119A and N119S being able to induce autonomous downstream signaling, overcome the limitation of ligand-receptor interaction for induction of CXCR4 signaling. Therefore, we intended to explore their potential in chemotaxis; a key cellular process which crucially regulates cells homing to bone marrow. In present study, Tet-on inducible gene expression vector system was used for doxycycline inducible regulated transgene expression of CXCR4 active mutants in hematopoietic stem progenitor cell line K-562. Both of these mutants revealed significantly enhanced chemotaxis to SDF-1 gradient as compared to wild type. Furthermore, gene expression profiling of these genetically engineered cells as assessed by microarray analysis revealed the up-regulation of group of genes that are known to play a crucial role in CXCR4 mediated cells homing and engraftment. Hence, this study suggest the potential prospects of CXCR4 active mutants in research and development aimed to improve the efficiency of cells in the mechanism of homing and engraftment process.

  9. Multiple myeloma cells recruit tumor-supportive macrophages through the CXCR4/CXCL12 axis and promote their polarization toward the M2 phenotype.

    Science.gov (United States)

    Beider, Katia; Bitner, Hanna; Leiba, Merav; Gutwein, Odit; Koren-Michowitz, Maya; Ostrovsky, Olga; Abraham, Michal; Wald, Hanna; Galun, Eithan; Peled, Amnon; Nagler, Arnon

    2014-11-30

    Multiple myeloma (MM) cells specifically attract peripheral-blood monocytes, while interaction of MM with bone marrow stromal cells (BMSCs) significantly increased monocyte recruitment (p<0.01). The CXCL12 chemokine, produced by both the MM and BMSCs, was found to be a critical regulator of monocyte migration. CXCL12 production was up-regulated under MM-BMSCs co-culture conditions, whereas blockage with anti-CXCR4 antibodies significantly abrogated monocyte recruitment toward a MM-derived conditioned medium (p<0.01). Furthermore, elevated levels of CXCL12 were detected in MM, but not in normal BM samples, whereas malignant MM cells often represented the source of increased CXCL12 in the BM. Blood-derived macrophages effectively supported MM cells proliferation and protected them from chemotherapy-induced apoptosis. Importantly, MM cells affected macrophage polarization, elevating the expression of M2-related scavenger receptor CD206 in macrophages and blocking LPS-induced TNFα secretion (a hallmark of M1 response). Of note, MM-educated macrophages suppressed T-cell proliferation and IFNγ production in response to activation. Finally, increased numbers of CXCR4-expressing CD163+CD206+ macrophages were detected in the BM of MM patients (n=25) in comparison to MGUS (n=11) and normal specimens (n=8). Taken together, these results identify macrophages as important players in MM tumorogenicity, and recognize the CXCR4/CXCL12 axis as a critical regulator of MM-stroma interactions and microenvironment formation.

  10. Construction of pBIFC-VN173-CXCR4 and pBIFC-VC155-NT21MP eukaryotic expression plasmids and their interaction in living cells%pBIFC-VN173-CXCR4和pBIFC-VC155-NT21MP真核表达质粒的构建及其在活细胞内的作用

    Institute of Scientific and Technical Information of China (English)

    高艳军; 杨清玲; 陈昌杰; 丁勇兴

    2012-01-01

    目的:构建pBIFC-VN173-CXCR4和pBIFC-VC 155-NT21MP真核表达质粒,利用双分子荧光互补( BiFC)技术,在活细胞内直接观察趋化因子受体4(chemokine receptor 4、CXCR4和CD184)与CXCR4抑制性多肽的相互作用.方法:应用化学合成法获得巨噬细胞炎症蛋白Ⅱ(viral macrophage inflammatory protein-Ⅱ,vMIP-Ⅱ)N端21肽(N-terminal 21-mer peptide,NT21MP)编码的基因序列,克隆至经Kpn Ⅰ和EcoR Ⅰ酶切的pBiFC-VC155中,筛选含有目标基因的正确克隆.利用RT-PCR扩增人乳腺癌细胞株SKBR3的CXCR4全长基因后,T-A亚克隆至经Kpn Ⅰ和EcoR Ⅰ酶切的pBiFC-VN173载体中.然后,经酶切鉴定及DNA测序分析2个基因是否正确连接至真核表达载体中.应用脂质体转染的方法共转染pBiFC-VC155-NT21 MP和pBiFC-VC155-CXCR4至细胞株COS-7中,在荧光显微镜下观察NT21MP与CXCR4在胞内的相互作用.结果:经DNA测序及同源性对比,证实pBiFC-VC155-NT21MP和pBiFC-VN173-CXCR4重组栽体构建成功;基因片段与NCBI基因库vMIP-Ⅱ和CXCR4基因CDS序列同源性达99.9%.BiFC法观察NT21MP与CXCR4在细胞内结合出现的荧光信号,该信号分布细胞内.结论:本实验成功构建了应用BiFC技术的真核表达载体,并且在活细胞内检测到NT21MP与CXCR4的互相结合.%Objective: To construct pBIFC-VN173-CXCR4 and pBIFC-VC155-NT21MP eukaryotic expression plasmids and to investigate the interaction of chemokine receptor 4 ( CXCR4) and viral macrophage inflammatory protein-Ⅱ ( vMIP-Ⅱ ) N terminal 21 peptides (NT21MP) in living cells. Methods; DNA fragment encoding NT21MP was chemically synthesized and inserted into BiFC eukaryotic expression vector pBIFC-VC155. The full length of CXCR4 DNA fragment was amplified by RT-PCR from SKBR3 cells and inserted into BiFC eukaryotic expression plasmid pBIFC-VN173. Two recombinant vectors were identified by restriction enzyme digestion and DNA sequencing. The recombinant vectors were cotransfected into

  11. Differential gene expression during capillary morphogenesis in a microcarrier-based three-dimensional in vitro model of angiogenesis with focus on chemokines and chemokine receptors

    Institute of Scientific and Technical Information of China (English)

    Xi-Tai Sun; Min-Yue Zhang; Chang Shu; Qiang Li; Xiao-Gui Yan; Ni Cheng; Yu-Dong Qiu; Yi-Tao Ding

    2005-01-01

    AIM: To globally compare the gene expression profiles during the capillary morphogenesis of human microvascular endothelial cells (HMVECs) in an in vitro angiogenesis system with affymetrix oligonucleotide array.METHODS: A microcarrier-based in vitro angiogenesis system was developed, in which ECs migrated into the matrix,proliferated, and formed capillary sprouts. The sprouts elongated, branched and formed networks. The total RNA samples from the HMVECs at the selected time points (0.5,24, and 72 h) during the capillary morphogenesis were used for microarray analyses, and the data were processed with the softwares provided by the manufacturers. The expression patterns of some genes were validated and confirmed by semi-quantitative RT-PCR. The regulated genes were grouped based on their molecular functions and expression patterns, and among them the expression of chemokines and chemokine receptors was specially examined and their functional implications were analyzed.RESULTS: A total of 1 961 genes were up- or downregulated two-folds or above, and among them, 468 genes were up- or down-regulated three-folds or above. The regulated genes could be grouped into categories based on their molecular functions, and were also clustered into six groups based on their patterns of expression. As for chemokines and chemokine receptors, CXCL1/GRO-α,CXCL2/GRO-β, CXCLS/ENA-78, CXCL6/GCP2, IL-8/CXCL8,CXCL12/SDF-1, CXCL9/Mig, CXC11/ITAC, CX3CL1/fractalkine,CCL2/MCP-1, CCL3, CCLS/RANTES, CCL7, CCL15, CCL21,CCL23, CCL28, and CCR1, CCR9, CXCR4 were identified.Moreover, these genes demonstrated different changing patterns during the capillary morphogenesis, which implied that they might have different roles in the sequential process. Among the chemokines identified, CCL2/MCP-1,CCL5/RANTES and CX3CL1 were specially up-regulated at the 24-h time point when the sprouting characterized the morphological change. It was thus suggested that they might exert crucial roles at the early stage

  12. Neuronal apoptotic signaling pathways probed and intervened by synthetically and modularly modified (SMM) chemokines.

    Science.gov (United States)

    Choi, Won-Tak; Kaul, Marcus; Kumar, Santosh; Wang, Jun; Kumar, I M Krishna; Dong, Chang-Zhi; An, Jing; Lipton, Stuart A; Huang, Ziwei

    2007-03-09

    As the main coreceptors for human immunodeficiency virus type 1 (HIV-1) entry, CXCR4 and CCR5 play important roles in HIV-associated dementia (HAD). HIV-1 glycoprotein gp120 contributes to HAD by causing neuronal damage and death, either directly by triggering apoptotic pathways or indirectly by stimulating glial cells to release neurotoxins. Here, to understand the mechanism of CXCR4 or CCR5 signaling in neuronal apoptosis associated with HAD, we have applied synthetically and modularly modified (SMM)-chemokine analogs derived from natural stromal cell-derived factor-1alpha or viral macrophage inflammatory protein-II as chemical probes of the mechanism(s) whereby these SMM-chemokines prevent or promote neuronal apoptosis. We show that inherently neurotoxic natural ligands of CXCR4, such as stromal cell-derived factor-1alpha or viral macrophage inflammatory protein-II, can be modified to protect neurons from apoptosis induced by CXCR4-preferring gp120(IIIB), and that the inhibition of CCR5 by antagonist SMM-chemokines, unlike neuroprotective CCR5 natural ligands, leads to neurotoxicity by activating a p38 mitogen-activated protein kinase (MAPK)-dependent pathway. Furthermore, we discover distinct signaling pathways activated by different chemokine ligands that are either natural agonists or synthetic antagonists, thus demonstrating a chemical biology strategy of using chemically engineered inhibitors of chemokine receptors to study the signaling mechanism of neuronal apoptosis and survival.

  13. Virally encoded chemokines and chemokine receptors in the role of viral infections

    DEFF Research Database (Denmark)

    Holst, Peter J; Lüttichau, Hans R; Schwartz, Thue W

    2003-01-01

    are the acquisition and modification of host-encoded chemokines and chemokine receptors. The described viral molecules leave nothing to chance and have thoroughly and efficiently corrupted the host immune system. Through this process viruses have identified key molecules in antiviral responses by their inhibition...... of these or potent ways to alter an efficient antiviral response to a weak Th2-driven response. Examples here are the chemokine scavenging by US28, attractance of Th2 cells and regulatory cells by vMIP1-3 and the selective engaging of CCR8 by MC148. Important insights into viral pathology and possible targets...... for antiviral therapies have been provided by UL33, UL78 and in particular ORF74 and the chances are that many more will follow. In HHV8 vMIP-2 and the chemokine-binding proteins potent anti-inflammatory agents have been provided. These have already had their potential demonstrated in animal models and may...

  14. Inhibition of SDF-1/CXCR4-induced epithelial-mesenchymal transition by kisspeptin-10.

    Science.gov (United States)

    Gründker, Carsten; Bauerschmitz, Gerd; Knapp, Juliane; Schmidt, Elena; Olbrich, Theresa; Emons, Günter

    2015-07-01

    , induction of EMT was inhibited. Furthermore, protein expression of the binding site of SDF-1, CXC-motive-chemokine receptor 4 (CXCR-4), was reduced by KP-10. Treatment of MCF-7-EMT cells with KP-10 resulted in a significant drop of cell invasion and CXCR-4 protein expression. Our findings suggest that SDF-1 plays a major role in breast cancer invasion and EMT. SDF-1-induced invasion and EMT can be inhibited by KP-10 treatment by down-regulating CXCR-4 expression.

  15. The role of SDF-1/CXCR4 in the vasculogenesis and remodeling of cerebral arteriovenous malformation

    Directory of Open Access Journals (Sweden)

    Wang L

    2015-09-01

    Full Text Available Lingyan Wang,1 Shaolei Guo,2 Nu Zhang,2 Yuqian Tao,3 Heng Zhang,1 Tiewei Qi,2 Feng Liang,2 Zhengsong Huang2 1Department of Neurosurgery ICU, 2Department of Neurosurgery, 3Department of Neurology, The First Affiliated Hospital of Sun Yat-Sen University, Guangzhou, People’s Republic of China Background: Cerebral arteriovenous malformation (AVM involves the vasculogenesis of cerebral blood vessels and can cause severe intracranial hemorrhage. Stromal cell-derived factor-1 (SDF-1 and its receptor, CXCR4, are believed to exert multiple physiological functions including angiogenesis. Thus, we investigated the role of SDF-1/CXCR4 in the vasculogenesis of cerebral AVM.Methods: Brain AVM lesions from surgical resections were analyzed for the expression of SDF-1, CXCR4, VEGF-A, and HIF-1 by using immunohistochemical staining. Flow cytometry was used to quantify the level of circulating endothelial progenitor cells (EPCs. Further, in an animal study, chronic cerebral hypoperfusion model rats were analyzed for the expression of SDF-1 and HIF-1. CXCR4 antagonist, AMD3100, was also used to detect its effects on cerebral vasculogenesis and SDF-1 expression.Results: Large amounts of CXCR4-positive CD45+ cells were found in brain AVM lesion blood vessel walls, which also have higher SDF-1 expression. Cerebral AVM patients also had higher level of EPCs and SDF-1. In chronic cerebral hypoperfusion rats, SDF-1, HIF-1, and CD45 expressions were elevated. The application of AMD3100 effectively suppressed angiogenesis and infiltration of CXCR4-positive CD45+ cells in hypoperfusion rats compared to controls.Conclusion: The SDF-1/CXCR4 axis plays an important role in the vasculogenesis and migration of inflammatory cells in cerebral AVM lesions, possibly via the recruitment of bone marrow EPCs. Keywords: cerebral arteriovenous malformation, SDF-1/CXCR4, chronic cerebral hypoperfusion, endothelial progenitor cells

  16. Type 1 chemokine receptor expression in Chagas' disease correlates with morbidity in cardiac patients.

    Science.gov (United States)

    Gomes, Juliana A S; Bahia-Oliveira, Lilian M G; Rocha, Manoel Otávio C; Busek, Solange C U; Teixeira, Mauro M; Silva, João Santana; Correa-Oliveira, Rodrigo

    2005-12-01

    Chemokines and chemokine receptors (CKRs) control the migration of leukocytes during the inflammatory process and are important immunological markers of type 1 (CCR5 and CXCR3) and type 2 (CCR3 and CCR4) responses. The coexpression of CKRs (CCR2, CCR3, CCR5, CXCR3, and CXCR4) and intracellular cytokines (interleukin-10 [IL-10], IL-4, tumor necrosis factor alpha [TNF-alpha], and gamma interferon [IFN-gamma]) on T CD4+ and CD8+ peripheral cells from individuals with indeterminate (IND) or cardiac (CARD) clinical forms of Chagas' disease after in vitro stimulation with Trypanosoma cruzi antigens, were evaluated in this study. The percentage of T CD4+ and CD8+ cells coexpressing CCR5 and IFN-gamma, CXCR3 and IFN-gamma, and CXCR3 and TNF-alpha were higher in CARD than in IND individuals; on the other hand, the percentage of T CD4+ or CD8+ cells coexpressing CCR3 and IL-10 or coexpressing CCR3 and IL-4 were lower in CARD individuals than in IND individuals. In addition, a significant positive correlation between the expression of CCR5 or CXCR3 and IFN-gamma was observed in CARD individuals contrasting with a significant positive correlation between the expression of CCR3 and IL-4 and of CCR3 and IL-10 in IND patients. These results reinforce the hypothesis that a T. cruzi-exacerbated specific type 1 immune response developed by CARD chagasic patients is associated with the development of heart pathology.

  17. Overexpression of SDF-1α enhanced migration and engraftment of cardiac stem cells and reduced infarcted size via CXCR4/PI3K pathway.

    Directory of Open Access Journals (Sweden)

    Kui Wang

    Full Text Available Cardiac stem cells (CSCs can home to the infarcted area and regenerate myocardium. Stromal cell-derived factor-1α/C-X-C chemokine receptor type 4 (SDF-1α/CXCR4 axis is pivotal in inducing CSCs migration. However, the mechanisms remain unclear. This study set out to detect if SDF-1α promotes migration and engraftment of CSCs through the CXCR4/PI3K (phosphatidylinositol 3-kinase pathway. In the in vitro experiment, c-kit+ cells were isolated from neonatal mouse heart fragment culture by magnetic cell sorting. Fluorescence-activated cell sorting results demonstrated that a few c-kit+ cells expressed CD45 (4.54% and Sca-1 (2.58%, the hematopoietic stem cell marker. Conditioned culture could induce c-kit+ cells multipotent differentiation, which was confirmed by cardiac troponin I (cTn-I, α-smooth muscle actin (α-SMA, and von Willebrand factor (vWF staining. In vitro chemotaxis assays were performed using Transwell cell chambers to detect CSCs migration. The results showed that the cardiomyocytes infected with rAAV1-SDF-1α-eGFP significantly increased SDF-1α concentration, 5-fold more in supernatant than that in the control group, and subsequently attracted more CSCs migration. This effect was diminished by administration of AMD3100 (10 µg/ml, CXCR4 antagonist or LY294002 (20 µmol/L, PI3K inhibitor. In myocardial infarction mice, overexpression of SDF-1α in the infarcted area by rAAV1-SDF-1α-eGFP infection resulted in more CSCs retention to the infarcted myocardium, a higher percentage of proliferation, and reduced infarcted area which was attenuated by AMD3100 or ly294002 pretreatment. These results indicated that overexpression of SDF-1α enhanced CSCs migration in vitro and engraftment of transplanted CSCs and reduced infarcted size via CXCR4/PI3K pathway.

  18. Distinct chemokine receptor and cytokine expression profile in secondary progressive MS

    DEFF Research Database (Denmark)

    Sørensen, Torben Lykke; Sellebjerg, F

    2001-01-01

    Chemokines, small chemotactic cytokines, have been implicated in active relapsing-remitting MS (RRMS). However, the role of chemokines and chemokine receptors has not been specifically studied in secondary progressive MS (SPMS)....

  19. The Study of the Regulation of HIF-1α for SDF-1/CXCR4 in Mesenchymal Stem Cells%HIF-1α对间充质干细胞SDF-1/CXCR4的调控作用研究

    Institute of Scientific and Technical Information of China (English)

    周丽萍; 余勤; 刘丽珍; 刘伟; 胡韶君

    2014-01-01

    [目的]探讨缺氧诱导因子-1α(hypoxia inducible factor-1α,HIF-1α)对间充质干细胞基质细胞衍生因子-1(stromal cel-derived factor-1, SDF-1)/ CXC趋化因子受体4(chemokine receptor 4,CXCR4)的调控作用。[方法]贴壁法培养ICR小鼠骨髓间充质干细胞(mesenchymal stem cel s,MSCs);采用RNA干扰技术用SuperFectinTMⅡ转染HIF-1α siRNA于MSCs;实验分为五组:常氧组、缺氧组、转染Control siRNA组、转染HIF-1αsiRNA常氧培养组、转染HIF-1αsiRNA缺氧培养组;RT-PCR检测HIF-1α、SDF-1α、CXCR4 mRNA表达水平;Western blotting检测HIF-1α、SDF-1α、CXCR4蛋白表达水平。[结果]同常氧组比较,缺氧组HIF-1α、SDF-1α、CXCR4 mRNA及蛋白表达水平提高(P<0.05);同转染Control siRNA组比较,转染HIF-1α siRNA常氧培养组HIF-1α、SDF-1α、CXCR4 mRNA及蛋白表达水平降低(P<0.05);同缺氧组比较,转染HIF-1αsiRNA缺氧培养组HIF-1α、SDF-1α、CXCR4 mRNA及蛋白表达水平降低(P<0.05)。[结论]缺氧可使MSCs的HIF-1α、SDF-1α、CX-CR4的表达提高,常氧与缺氧条件下抑制HIF-1α的表达可使SDF-1α、CXCR4的表达降低,HIF-1α在间充质干细胞中对SDF-1/CXCR4有调控作用。%[Aim] To study the regulation of HIF-1α for SDF-1/CXCR4 in MSCs. [Methods] MSCs were cultured by adherence method. HIF-1αsiRNA was transfected to MSCs by SuperFectinTM Ⅱ. The experiment was divided into five groups, normoxia group,hypoxia group,control siRNA transfected group, HIF-1α siRNA transfected normoxic group, HIF-1α siRNA transfected hypoxia group. Reverse transcdption-polymerase chain reaction was utilized to determine HIF-1α, SDF-1α, CXCR4 mRNA expression in MSCs.Western blotting was employed to detect HIF-1α, SDF-1α, CXCR4 protein expression in MSCs. [Result] Compared with the normoxia group, HIF-1α, SDF-1α and CXCR4 mRNA and protein expression increased in the hypoxia group(P<0.05). Compared

  20. ACKR2: An Atypical Chemokine Receptor Regulating Lymphatic Biology

    Science.gov (United States)

    Bonavita, Ornella; Mollica Poeta, Valeria; Setten, Elisa; Massara, Matteo; Bonecchi, Raffaella

    2017-01-01

    The lymphatic system plays an important role in the induction of the immune response by transporting antigens, inflammatory mediators, and leukocytes from peripheral tissues to draining lymph nodes. It is emerging that lymphatic endothelial cells (LECs) are playing an active role in this context via the expression of chemokines, inflammatory mediators promoting cell migration, and chemokine receptors. Particularly, LECs express atypical chemokine receptors (ACKRs), which are unable to promote conventional signaling and cell migration while they are involved in the regulation of chemokine availability. Here, we provide a summary of the data on the role of ACKR2 expressed by lymphatics, indicating an essential role for this ACKRs in the regulation of the inflammation and the immune response in different pathological conditions, including infection, allergy, and cancer. PMID:28123388

  1. Chemokines and Chemokine Receptors as Novel Therapeutic Targets in Rheumatoid Arthritis (RA): Inhibitory Effects of Traditional Chinese Medicinal Components

    Institute of Scientific and Technical Information of China (English)

    Xin Chen; Joost J. Oppenheim; O.M.Zack Howard

    2004-01-01

    Chemokines belong to a large family of inflammatory cytokines responsible for migration and accumulation of leukocytes at inflammatory sites. Over the past decade, accumulating evidence indicated a crucial role for chemokines and chemokine receptors in the pathophysiology of rheumatoid arthritis (RA). RA is a chronic autoimmune disease in which the synovial tissue is heavily infiltrated by leukocytes. Chemokines play an important role in the infiltration, localization, retention of infiltrating leukocytes and generation of ectopic germinal centers in the inflamed synovium. Recent evidence also suggests that identification of inhibitors directly targeting chemokines or their receptors may provide a novel therapeutic strategy in RA. Traditional Chinese medicinals (TCMs) have a long history in the treatment of inflammatory joint disease. The basis for the clinical benefits of TCM remains largely unclear. Our studies have led to the identification of numerous novel chemokine/chemokine receptor inhibitors present in anti-inflammatory TCMs. All of these inhibitors were previously reported by other researchers to have anti-arthritic effect, which may be attributable, at least in part, to their inhibitory effect on chemokine and/or chemokine receptor. Therefore, identification of agents capable of targeting chemokine/chemokine receptor interactions has suggested a mechanism of action for several TCM components and provided a means of identifying additional anti-RA TCM. Thus, this approach may lead to the discovery of new inhibitors of chemokines or chemokine receptors that can be used to treat diseases associated with inappropriately overactive chemokine mediated inflammatory reactions. Cellular & Molecular Immunology. 2004;1(5):336-342.

  2. C-terminal engineering of CXCL12 and CCL5 chemokines: functional characterization by electrophysiological recordings.

    Directory of Open Access Journals (Sweden)

    Antoine Picciocchi

    Full Text Available Chemokines are chemotactic cytokines comprised of 70-100 amino acids. The chemokines CXCL12 and CCL5 are the endogenous ligands of the CXCR4 and CCR5 G protein-coupled receptors that are also HIV co-receptors. Biochemical, structural and functional studies of receptors are ligand-consuming and the cost of commercial chemokines hinders their use in such studies. Here, we describe methods for the expression, refolding, purification, and functional characterization of CXCL12 and CCL5 constructs incorporating C-terminal epitope tags. The model tags used were hexahistidines and Strep-Tag for affinity purification, and the double lanthanoid binding tag for fluorescence imaging and crystal structure resolution. The ability of modified and purified chemokines to bind and activate CXCR4 and CCR5 receptors was tested in Xenopus oocytes expressing the receptors, together with a Kir3 G-protein activated K(+ channel that served as a reporter of receptor activation. Results demonstrate that tags greatly influence the biochemical properties of the recombinant chemokines. Besides, despite the absence of any evidence for CXCL12 or CCL5 C-terminus involvement in receptor binding and activation, we demonstrated unpredictable effects of tag insertion on the ligand apparent affinity and efficacy or on the ligand dissociation. These tagged chemokines should constitute useful tools for the selective purification of properly-folded chemokines receptors and the study of their native quaternary structures.

  3. CXCL12 chemokine and GABA neurotransmitter systems crosstalk and their putative roles

    Directory of Open Access Journals (Sweden)

    Guyon eAlice

    2014-04-01

    Full Text Available Since CXCL12 and its receptors, CXCR4 and CXCR7, have been found in the brain, the role of this chemokine has been expanded from chemoattractant in the immune system to neuromodulatory in the brain. Several pieces of evidence suggest that this chemokine system could crosstalk with the GABAergic system, known to be the main inhibitory neurotransmitter system in the brain. Indeed, GABA and CXCL12 as well as their receptors are colocalized in many cell types including neurons and there are several examples in which these two systems interact. Several mechanisms can be proposed to explain how these systems interact, including receptor-receptor interactions, crosstalk at the level of second messenger cascades, or direct pharmacological interactions, as GABA and GABAB receptor agonists/antagonists have been shown to be allosteric modulators of CXCR4.The interplay between CXCL12/CXCR4-CXCR7 and GABA/GABAA-GABAB receptors systems could have many physiological implications in neurotransmission, cancer and inflammation. In addition, the GABAB agonist baclofen is currently used in medicine to treat spasticity in patients with spinal cord injury, cerebral palsy, traumatic brain injury, multiple sclerosis and other disorders. More recently it has also been used in the treatment of alcohol dependence and withdrawal. The allosteric effects of this agent on CXCR4 could contribute to these beneficial effects or at the opposite, to its side effects.

  4. Chemokine receptor expression by inflammatory T cells in EAE

    DEFF Research Database (Denmark)

    Mony, Jyothi Thyagabhavan; Khorooshi, Reza; Owens, Trevor

    2014-01-01

    Chemokines direct cellular infiltration to tissues, and their receptors and signaling pathways represent targets for therapy in diseases such as multiple sclerosis (MS). The chemokine CCL20 is expressed in choroid plexus, a site of entry of T cells to the central nervous system (CNS). The CCL20...... receptor CCR6 has been reported to be selectively expressed by CD4(+) T cells that produce the cytokine IL-17 (Th17 cells). Th17 cells and interferon-gamma (IFNγ)-producing Th1 cells are implicated in induction of MS and its animal model experimental autoimmune encephalomyelitis (EAE). We have assessed...... whether CCR6 identifies specific inflammatory T cell subsets in EAE. Our approach was to induce EAE, and then examine chemokine receptor expression by cytokine-producing T cells sorted from CNS at peak disease. About 7% of CNS-infiltrating CD4(+) T cells produced IFNγ in flow cytometric cytokine assays...

  5. CXCR4 signaling regulates radial glial morphology and cell fate during embryonic spinal cord development.

    Science.gov (United States)

    Mithal, Divakar S; Ren, Dongjun; Miller, Richard J

    2013-08-01

    Embryonic meninges secrete the chemokine SDF-1/CXCL12 as a chemotactic guide for migrating neural stem cells, but SDF-1 is not known to directly regulate the functions of radial glia. Recently, the developing meninges have been shown to regulate radial glial function, yet the mechanisms and signals responsible for this phenomenon remain unclear. Moreover, as a nonmigratory cell type, radial glia do not conform to traditional models associated with chemokine signaling in the central nervous system. Using fluorescent transgenes, in vivo genetic manipulations and pharmacological techniques, we demonstrate that SDF-1 derived from the meninges exerts a CXCR4-dependent effect on radial glia. Deletion of CXCR4 expression by radial glia influences their morphology, mitosis, and progression through both oligodendroglial and astroglial lineages. Additionally, disruption of CXCR4 signaling in radial glia has a transient effect on the migration of oligodendrocyte progenitors. These data indicate that a specific chemokine signal derived from the meninges has multiple regulatory effects on radial glia.

  6. CCR5/CD4/CXCR4 oligomerization prevents HIV-1 gp120IIIB binding to the cell surface.

    Science.gov (United States)

    Martínez-Muñoz, Laura; Barroso, Rubén; Dyrhaug, Sunniva Y; Navarro, Gemma; Lucas, Pilar; Soriano, Silvia F; Vega, Beatriz; Costas, Coloma; Muñoz-Fernández, M Ángeles; Santiago, César; Rodríguez Frade, José Miguel; Franco, Rafael; Mellado, Mario

    2014-05-13

    CCR5 and CXCR4, the respective cell surface coreceptors of R5 and X4 HIV-1 strains, both form heterodimers with CD4, the principal HIV-1 receptor. Using several resonance energy transfer techniques, we determined that CD4, CXCR4, and CCR5 formed heterotrimers, and that CCR5 coexpression altered the conformation of both CXCR4/CXCR4 homodimers and CD4/CXCR4 heterodimers. As a result, binding of the HIV-1 envelope protein gp120IIIB to the CD4/CXCR4/CCR5 heterooligomer was negligible, and the gp120-induced cytoskeletal rearrangements necessary for HIV-1 entry were prevented. CCR5 reduced HIV-1 envelope-induced CD4/CXCR4-mediated cell-cell fusion. In nucleofected Jurkat CD4 cells and primary human CD4(+) T cells, CCR5 expression led to a reduction in X4 HIV-1 infectivity. These findings can help to understand why X4 HIV-1 strains infection affect T-cell types differently during AIDS development and indicate that receptor oligomerization might be a target for previously unidentified therapeutic approaches for AIDS intervention.

  7. Inhibition of Human Immunodeficiency Virus Replication by a Dual CCR5/CXCR4 Antagonist

    Science.gov (United States)

    Princen, Katrien; Hatse, Sigrid; Vermeire, Kurt; Aquaro, Stefano; De Clercq, Erik; Gerlach, Lars-Ole; Rosenkilde, Mette; Schwartz, Thue W.; Skerlj, Renato; Bridger, Gary; Schols, Dominique

    2004-01-01

    Here we report that the N-pyridinylmethyl cyclam analog AMD3451 has antiviral activity against a wide variety of R5, R5/X4, and X4 strains of human immunodeficiency virus type 1 (HIV-1) and HIV-2 (50% inhibitory concentration [IC50] ranging from 1.2 to 26.5 μM) in various T-cell lines, CCR5- or CXCR4-transfected cells, peripheral blood mononuclear cells (PBMCs), and monocytes/macrophages. AMD3451 also inhibited R5, R5/X4, and X4 HIV-1 primary clinical isolates in PBMCs (IC50, 1.8 to 7.3 μM). A PCR-based viral entry assay revealed that AMD3451 blocks R5 and X4 HIV-1 infection at the virus entry stage. AMD3451 dose-dependently inhibited the intracellular Ca2+ signaling induced by the CXCR4 ligand CXCL12 in T-lymphocytic cells and in CXCR4-transfected cells, as well as the Ca2+ flux induced by the CCR5 ligands CCL5, CCL3, and CCL4 in CCR5-transfected cells. The compound did not interfere with chemokine-induced Ca2+ signaling through CCR1, CCR2, CCR3, CCR4, CCR6, CCR9, or CXCR3 and did not induce intracellular Ca2+ signaling by itself at concentrations up to 400 μM. In freshly isolated monocytes, AMD3451 inhibited the Ca2+ flux induced by CXCL12 and CCL4 but not that induced by CCL2, CCL3, CCL5, and CCL7. The CXCL12- and CCL3-induced chemotaxis was also dose-dependently inhibited by AMD3451. Furthermore, AMD3451 inhibited CXCL12- and CCL3L1-induced endocytosis in CXCR4- and CCR5-transfected cells. AMD3451, in contrast to the specific CXCR4 antagonist AMD3100, did not inhibit but enhanced the binding of several anti-CXCR4 monoclonal antibodies (such as clone 12G5) at the cell surface, pointing to a different interaction with CXCR4. AMD3451 is the first low-molecular-weight anti-HIV agent with selective HIV coreceptor, CCR5 and CXCR4, interaction. PMID:15542651

  8. Chemokine-guided angiogenesis directs coronary vasculature formation in zebrafish.

    Science.gov (United States)

    Harrison, Michael R M; Bussmann, Jeroen; Huang, Ying; Zhao, Long; Osorio, Arthela; Burns, C Geoffrey; Burns, Caroline E; Sucov, Henry M; Siekmann, Arndt F; Lien, Ching-Ling

    2015-05-26

    Interruption of the coronary blood supply severely impairs heart function with often fatal consequences for patients. However, the formation and maturation of these coronary vessels is not fully understood. Here we provide a detailed analysis of coronary vessel development in zebrafish. We observe that coronary vessels form in zebrafish by angiogenic sprouting of arterial cells derived from the endocardium at the atrioventricular canal. Endothelial cells express the CXC-motif chemokine receptor Cxcr4a and migrate to vascularize the ventricle under the guidance of the myocardium-expressed ligand Cxcl12b. cxcr4a mutant zebrafish fail to form a vascular network, whereas ectopic expression of Cxcl12b ligand induces coronary vessel formation. Importantly, cxcr4a mutant zebrafish fail to undergo heart regeneration following injury. Our results suggest that chemokine signaling has an essential role in coronary vessel formation by directing migration of endocardium-derived endothelial cells. Poorly developed vasculature in cxcr4a mutants likely underlies decreased regenerative potential in adults.

  9. Chemokine expression in hepatocellular carcinoma versus colorectal liver metastases

    Institute of Scientific and Technical Information of China (English)

    Claudia Rubie; Vilma Oliveira Frick; Mathias Wagner; Christina Weber; Bianca Kruse; Katja Kempf; Jochen K(o)nig; Bettina Rau; Martin Schilling

    2006-01-01

    AIM: To evaluate and compare the expression profiles of CXCL12 (SDF-1), CCL19 (MIP-3β), CCL20 (MIP-3α) and CCL21 (6Ckine, Exodus2) and their receptors on RNA and protein levels in hepatocellular carcinoma (HCC) versus colorectal liver metastases (CRLM) and to elucidate their impact on the carcinogenesis and progression of malignant liver diseases.METHODS: Chemokine expression was analyzed by RT-PCR and ELISA in 11 cases of HCC specimens and in 23 cases of CRLM and corresponding adjacent nontumorous liver tissues, respectively. Expressions of their receptors CXCR4, CCR6 and CCR7 were analyzed by RTPCR and Western blot analysis in the same cases of HCC and CRLM.RESULTS: Significant up-regulation for CCL20/CCR6 was detected in both cancer types. Moreover, CCL20demonstrated significant overexpression in CRLM in relation to the HCC tissues. Being significantly upregulated only in CRLM, CXCR4 displayed an aberrant expression pattern with respect to the HCC tissues.CONCLUSION: Correlation of CXCR4 expression with CRLM suggests CXCR4 as a potential predictive factor for CRLM. High level expression of CCL20 and its receptor CCR6 in HCC and CRLM with marked upregulation of CCL20 in CRLM in relation to HCC tissues indicates involvement of the CCL20/CCR6 ligand-receptor pair in the carcinogenesis and progression of hepatic malignancies.

  10. Biased signaling of G protein-coupled receptors - From a chemokine receptor CCR7 perspective

    DEFF Research Database (Denmark)

    Jørgensen, Astrid Sissel; Rosenkilde, Mette M; Hjortø, Gertrud M

    2017-01-01

    Chemokines (chemotactic cytokines) and their associated G protein-coupled receptors (GPCRs) work in a concerted manner to govern immune cell positioning in time and space. Promiscuity of both ligands and receptors, but also biased signaling within the chemokine system, adds to the complexity of how...

  11. Radiation-induced lung damage promotes breast cancer lung-metastasis through CXCR4 signaling

    Science.gov (United States)

    Feys, Lynn; Descamps, Benedicte; Vanhove, Christian; Vral, Anne; Veldeman, Liv; Vermeulen, Stefan; De Wagter, Carlos; Bracke, Marc; De Wever, Olivier

    2015-01-01

    Radiotherapy is a mainstay in the postoperative treatment of breast cancer as it reduces the risks of local recurrence and mortality after both conservative surgery and mastectomy. Despite recent efforts to decrease irradiation volumes through accelerated partial irradiation techniques, late cardiac and pulmonary toxicity still occurs after breast irradiation. The importance of this pulmonary injury towards lung metastasis is unclear. Preirradiation of lung epithelial cells induces DNA damage, p53 activation and a secretome enriched in the chemokines SDF-1/CXCL12 and MIF. Irradiated lung epithelial cells stimulate adhesion, spreading, growth, and (transendothelial) migration of human MDA-MB-231 and murine 4T1 breast cancer cells. These metastasis-associated cellular activities were largely mimicked by recombinant CXCL12 and MIF. Moreover, an allosteric inhibitor of the CXCR4 receptor prevented the metastasis-associated cellular activities stimulated by the secretome of irradiated lung epithelial cells. Furthermore, partial (10%) irradiation of the right lung significantly stimulated breast cancer lung-specific metastasis in the syngeneic, orthotopic 4T1 breast cancer model. Our results warrant further investigation of the potential pro-metastatic effects of radiation and indicate the need to develop efficient drugs that will be successful in combination with radiotherapy to prevent therapy-induced spread of cancer cells. PMID:26396176

  12. Phenotypic Knockout of CXCR4 on Molt-4 with SDF-1α/54 Attached with KDEL

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Objective :To investigate the mechanism of phenotypic knockout of CXCR4 on T-cell leukemia cell line Molt-4 via SDF-1α/54/KDEL intrakine technology, which the mutant SDF-1α/54, human stromal cell-derived Faceor-1 (SDF-1α) was deleted its Cterminal α-helix and attached with a endoplasimc reticulum retention signal 4-peptide-KDEL encoding gene, so that retain the newly synthesized receptor CXCR4 within the Molt-4 cells endoplasmic reticulum. Methods: The recombinant vector pEGFP-C3/SDF-1α/54/KDEL were transfected into Cos-7 cells by liposome, SDF-1α/54/KDEL fusion protein was confirmed with western blot. The recombinant plasmids were transfected transiently into Molt-4 by electroporation. Results:Western blot confirmed SDF-1α/54/KDEL expression in Cos-7. A dramatic downregulation of CXCR4 expression on Molt-4 was demonstrated by flow cytometric (FCM) analysis. Conclusion:SDF-1α/54/KDEL and SDF-1αKDEL have no significant deviation for phenotypic knockout of CXCR4. These suggest that the phenotypic knockout effects of SDF-1α/54 against CXCR4 are not influenced by deleting of SDF-1α helix in the C-terminal.

  13. Hologram quantitative structure activity relationship, docking, and molecular dynamics studies of inhibitors for CXCR4.

    Science.gov (United States)

    Zhang, Chongqian; Du, Chunmiao; Feng, Zhiwei; Zhu, Jingyu; Li, Youyong

    2015-02-01

    CXCR4 plays a crucial role as a co-receptor with CCR5 for HIV-1 anchoring to mammalian cell membrane and is implicated in cancer metastasis and inflammation. In the current work, we study the relationship of structure and activity of AMD11070 derivatives and other inhibitors of CXCR4 using HQSAR, docking and molecular dynamics (MD) simulations. We obtain an HQSAR model (q(2) = 0.779), and the HQSAR result illustrates that AMD11070 shows a high antiretroviral activity. As HQSAR only provides 2D information, we perform docking and MD to study the interaction of It1t, AMD3100, and AMD3465 with CXCR4. Our results illustrate that the binding are affected by two crucial residues Asp97 and Glu288. The butyl amine moiety of AMD11070 contributes to its high antiretroviral activity. Without a butyl amine moiety, (2,7a-Dihydro-1H-benzoimidazol-2-ylmethyl)-methyl-(5,6,7,8-tetrahydro-quinolin-8-yl)-amine (compound 5a) shows low antiretroviral activity. Our results provide structural details about the interactions between the inhibitors and CXCR4, which are useful for rational drug design of CXCR4.

  14. Drug Design Targeting the CXCR4/CXCR7/CXCL12 Pathway.

    Science.gov (United States)

    Xu, Dongsheng; Li, Rongshi; Wu, Jianguo; Jiang, Li; Zhong, Haizhen A

    2016-01-01

    Under physiological conditions, CXCL12 modulates cell proliferation, survival, angiogenesis, and migration mainly through CXCR4. Interestingly, the newly discovered receptor CXCR7 for CXCL12 is highly expressed in many tumor cells as well as tumor-associated blood vessels, although the level of CXCR7 in normal blood cells is low. Recently, many studies have suggested that CXCR7 promotes cell growth and metastasis in various cancers, including lymphoma and leukemia, hepatocecullar, ovarian, colorectal, breast and lung cancer. Compared to CXCR4, CXCR7 is a non-classical GPCR that is unable to activate G proteins. The function of CXCR7 is generally considered to be mediated by: (a) recruiting β-arrestin-2; (b) heterodimerizing with CXCR4; and (c) acting as a "scavenger" of CXCL12, thus lowering the level of CXCL12 to weaken the activity of CXCR4. However, the crosstalk between CXCL12/CXCR7/CXCR4 and other signaling pathways (such as the p38 MAPK pathway, the PI3K/mTOR pathway, the STAT3 signaling, and metalloproteinases MMP-9 and MMP-2) is more complicated. The function of CXCR7 is also involved in modulating tumor microenvironment, tumor cell migration and apoptosis. Understanding these complex interactions will provide insight in drug design targeting the CXCR7 as potential anticancer therapy.

  15. CXCR4 inhibitors could benefit to HER2 but not to triple-negative breast cancer patients.

    Science.gov (United States)

    Lefort, S; Thuleau, A; Kieffer, Y; Sirven, P; Bieche, I; Marangoni, E; Vincent-Salomon, A; Mechta-Grigoriou, F

    2017-03-02

    The CXCR4 receptor and its ligand CXCL12 (also named stromal cell-derived factor 1, SDF1) have a critical role in chemotaxis and homing, key steps in cancer metastasis. Although myofibroblasts expressing CXCL12 are associated with the presence of axillary metastases in HER2 breast cancers (BC), the therapeutic interest of targeting CXCR4/CXCL12 axis in the different BC subtypes remains unclear. Here, we investigate this question by testing antitumor activity of CXCR4 inhibitors in patient-derived xenografts (PDX), which faithfully reproduce human tumor properties. We observed that two CXCR4 inhibitors, AMD3100 and TN14003, efficiently impair tumor growth and metastasis dissemination in both Herceptin-sensitive and Herceptin-resistant HER2 BC. Conversely, blocking CXCR4/CXCL12 pathway in triple-negative (TN) BC does not reduce tumor growth, and can even increase metastatic spread. Moreover, although CXCR4 inhibitors significantly reduce myofibroblast content in all BC subtypes, they decrease angiogenesis only in HER2 BC. Thus, our findings suggest that targeting CXCR4 could provide some therapeutic interest for HER2 BC patients, whereas it has no impact or could even be detrimental for TN BC patients.

  16. CXCR4 inhibitors could benefit to HER2 but not to triple-negative breast cancer patients

    Science.gov (United States)

    Lefort, S; Thuleau, A; Kieffer, Y; Sirven, P; Bieche, I; Marangoni, E; Vincent-Salomon, A; Mechta-Grigoriou, F

    2017-01-01

    The CXCR4 receptor and its ligand CXCL12 (also named stromal cell-derived factor 1, SDF1) have a critical role in chemotaxis and homing, key steps in cancer metastasis. Although myofibroblasts expressing CXCL12 are associated with the presence of axillary metastases in HER2 breast cancers (BC), the therapeutic interest of targeting CXCR4/CXCL12 axis in the different BC subtypes remains unclear. Here, we investigate this question by testing antitumor activity of CXCR4 inhibitors in patient-derived xenografts (PDX), which faithfully reproduce human tumor properties. We observed that two CXCR4 inhibitors, AMD3100 and TN14003, efficiently impair tumor growth and metastasis dissemination in both Herceptin-sensitive and Herceptin-resistant HER2 BC. Conversely, blocking CXCR4/CXCL12 pathway in triple-negative (TN) BC does not reduce tumor growth, and can even increase metastatic spread. Moreover, although CXCR4 inhibitors significantly reduce myofibroblast content in all BC subtypes, they decrease angiogenesis only in HER2 BC. Thus, our findings suggest that targeting CXCR4 could provide some therapeutic interest for HER2 BC patients, whereas it has no impact or could even be detrimental for TN BC patients. PMID:27669438

  17. Chemokine Receptor 7 Knockout Attenuates Atherosclerotic Plaque Development

    NARCIS (Netherlands)

    Luchtefeld, Maren; Grothusen, Christina; Gagalick, Andreas; Jagavelu, Kumaravelu; Schuett, Harald; Tietge, Uwe J. F.; Pabst, Oliver; Grote, Karsten; Drexler, Helmut; Foerster, Reinhold; Schieffer, Bernhard

    2010-01-01

    Background-Atherosclerosis is a systemic inflammatory disease characterized by the formation of atherosclerotic plaques. Both innate immunity and adaptive immunity contribute to atherogenesis, but the mode of interaction is poorly understood. Chemokine receptor 7 (CCR7) is critically involved in the

  18. Chemokine receptor CCR5 in interferon-treated multiple sclerosis

    DEFF Research Database (Denmark)

    Sellebjerg, F; Kristiansen, Thomas Birk; Wittenhagen, P

    2007-01-01

    OBJECTIVE: To study the relationship between CC chemokine receptor CCR5 expression and disease activity in multiple sclerosis (MS) patients treated with beta-interferon (IFN-beta). METHODS: The CCR5 Delta32 allele and a CCR5 promoter polymorphism associated with cell surface expression of CCR5 were...

  19. The rhesus macaque CCR3 chemokine receptor is a cell entry cofactor for HIV-2, but not for HIV-1.

    Science.gov (United States)

    Sol, N; Tréboute, C; Gomas, E; Ferchal, F; Shacklett, B; Alizon, M

    1998-01-20

    The eotaxin receptor (CCR3) is a CD4-associated coreceptor for human immunodeficiency virus type 1 (HIV-1) and type 2 (HIV-2). By comparison with other chemokine receptors, such as CCR5 and CXCR4, the primary sequences of human CCR3 and its rhesus macaque homolog were markedly different in their extracellular domains. Human CD4+ cells expressing CCR3 from either human or macaque origin could be infected by HIV-2, with apparently similar efficiency, but only cells expressing human CCR3 could be infected by HIV-1. It suggests that HIV-1 and HIV-2 envelope proteins interact differently with the CCR3 coreceptor HIV-1 could infect cells expressing chimeric human/macaque CCR3 bearing either the first and second, or the third and fourth extracellular domains of human CCR3. As previously observed for CCR5, there seems to be a certain functional redundancy between domains supporting the coreceptor activity of CCR3. In spite of their close genetic relationship to HIV-2, two macaque simian immunodeficiency virus strains were apparently unable to use the CCR3 coreceptor from either human or simian origin.

  20. Spatiotemporal presentation of exogenous SDF-1 with PLGA nanoparticles modulates SDF-1/CXCR4 signaling axis in the rodent cortex.

    Science.gov (United States)

    Dutta, D; Hickey, K; Salifu, M; Fauer, C; Willingham, C; Stabenfeldt, S E

    2017-07-25

    Stromal cell-derived factor-1 (SDF-1) and its key receptor CXCR4 have been implicated in directing cellular recruitment for several pathological/disease conditions thus also gained considerable attention for regenerative medicine. One regenerative approach includes sustained release of SDF-1 to stimulate prolonged stem cell recruitment. However, the impact of SDF-1 sustained release on the endogenous SDF-1/CXCR4 signaling axis is largely unknown as auto-regulatory mechanisms typically dictate cytokine/receptor signaling. We hypothesize that spatiotemporal presentation of exogenous SDF-1 is a key factor in achieving long-term manipulation of endogenous SDF-1/CXCR4 signaling. Here in the present study, we sought to probe our hypothesis using a transgenic mouse model to contrast the spatial activation of endogenous SDF-1 and CXCR4 in response to exogenous SDF-1 injected in bolus or controlled release (PLGA nanoparticles) form in the adult rodent cortex. Our data suggests that the manner of SDF-1 presentation significantly affected initial CXCR4 cellular activation/recruitment despite having similar protein payloads over the first 24 h (∼30 ng for both bolus and sustained release groups). Yet, one week post-injection, this response was negligible. Therefore, the transient nature CXCR4 recruitment/activation in response to bolus or controlled release SDF-1 indicated that cytokine/receptor auto-regulatory mechanisms may demand more complex release profiles (i.e. delayed and/or pulsed release) to achieve sustained cellular response.

  1. Short-term intermittent administration of CXCR4 antagonist AMD3100 facilitates myocardial repair in experimental myocardial infarction

    Institute of Scientific and Technical Information of China (English)

    Yuechen Luo; Xiaoning Zhao; Xin Zhou; Wenjie Ji; Ling Zhang; Tao Luo; Hongrnei Liu

    2013-01-01

    The binding of the stromal cell-derived factor-1α (SDF-1α)to the cysteine (C)-X-C motif chemokine receptor 4 (CXCR4) has emerged as a key signal for stem and progenitor cells trafficking to the circulation from the bone marrow.Our aim was to investigate the role of daily intermittent administration of AMD3100 (a specific reversible CXCR4 receptor antagonist) during the healing process after myocardial infarction (MI).Wistar rats were subjected to MI and AMD3100 was injected intraperitoneally after surgery.SDF-1α mRNA expression was measured by real-time polymerase chain reaction.Histology changes were analyzed with immunofluorescence,Masson's trichrome staining,and wheat germ agglutinin.The number of leukocytes in peripheral blood was measured by complete blood cell count analysis.The activities of matrix metalloproteinase-2/9 (MMP-2/9) were determined by gelatin zymography.The expression level of SDF-1αmRNA in the infarcted tissue was enhanced rapidly (6 h),peaked at 24 h,and then declined to the normal level at 7days post-MI.AMD3100 further enhanced the increase of SDF-1α in infarct area.Increased leukocytes were observed in AMD3100-treated groups.The mobilization of c-kit+ stem/progenitor cells and enhanced neovascularization were augmented by AMD3100.Additionally,AMD3100 improved ventricular remodeling,which was revealed by the decrease of infarct size,viable cardiomyocyte cross-sectional area and left ventricle (LV) expansion index,and the increase of LV free wall thickness.The activities of MMP-2/9 were up-regulated by AMD3100.In conclusion,short-term intermittent administration of AMD3100 could accelerate the wound healing process in experimental MI and be a potential therapy for the treatment of MI.

  2. RasGRP1, but not RasGRP3, is required for efficient thymic β-selection and ERK activation downstream of CXCR4.

    Directory of Open Access Journals (Sweden)

    Dominic P Golec

    Full Text Available T cell development is a highly dynamic process that is driven by interactions between developing thymocytes and the thymic microenvironment. Upon entering the thymus, the earliest thymic progenitors, called CD4(-CD8(- 'double negative' (DN thymocytes, pass through a checkpoint termed "β-selection" before maturing into CD4(+CD8(+ 'double positive' (DP thymocytes. β-selection is an important developmental checkpoint during thymopoiesis where developing DN thymocytes that successfully express the pre-T cell receptor (TCR undergo extensive proliferation and differentiation towards the DP stage. Signals transduced through the pre-TCR, chemokine receptor CXCR4 and Notch are thought to drive β-selection. Additionally, it has long been known that ERK is activated during β-selection; however the pathways regulating ERK activation remain unknown. Here, we performed a detailed analysis of the β-selection events in mice lacking RasGRP1, RasGRP3 and RasGRP1 and 3. We report that RasGRP1 KO and RasGRP1/3 DKO deficient thymi show a partial developmental block at the early DN3 stage of development. Furthermore, DN3 thymocytes from RasGRP1 and RasGRP1/3 double knock-out thymi show significantly reduced proliferation, despite expression of the TCRβ chain. As a result of impaired β-selection, the pool of TCRβ(+ DN4 is significantly diminished, resulting in inefficient DN to DP development. Also, we report that RasGRP1 is required for ERK activation downstream of CXCR4 signaling, which we hypothesize represents a potential mechanism of RasGRP1 regulation of β-selection. Our results demonstrate that RasGRP1 is an important regulator of proliferation and differentiation at the β-selection checkpoint and functions downstream of CXCR4 to activate the Ras/MAPK pathway.

  3. What Do Structures Tell Us About Chemokine Receptor Function and Antagonism?

    Energy Technology Data Exchange (ETDEWEB)

    Kufareva, Irina; Gustavsson, Martin; Zheng, Yi; Stephens, Bryan S.; Handel, Tracy M. (UCSD)

    2017-05-22

    Chemokines and their cell surface G protein–coupled receptors are critical for cell migration, not only in many fundamental biological processes but also in inflammatory diseases and cancer. Recent X-ray structures of two chemokines complexed with full-length receptors provided unprecedented insight into the atomic details of chemokine recognition and receptor activation, and computational modeling informed by new experiments leverages these insights to gain understanding of many more receptor:chemokine pairs. In parallel, chemokine receptor structures with small molecules reveal the complicated and diverse structural foundations of small molecule antagonism and allostery, highlight the inherent physicochemical challenges of receptor:chemokine interfaces, and suggest novel epitopes that can be exploited to overcome these challenges. The structures and models promote unique understanding of chemokine receptor biology, including the interpretation of two decades of experimental studies, and will undoubtedly assist future drug discovery endeavors.

  4. Superoxide Dismutase 1 Regulation of CXCR4-Mediated Signaling in Prostate Cancer Cells is Dependent on Cellular Oxidative State

    Directory of Open Access Journals (Sweden)

    Brent Young

    2015-11-01

    Full Text Available Background/Aims: CXCL12, acting via one of its G protein-coupled receptors, CXCR4, is a chemoattractant for a broad range of cell types, including several types of cancer cells. Elevated expression of CXCR4, and its ligand CXCL12, play important roles in promoting cancer metastasis. Cancer cells have the potential for rapid and unlimited growth in an area that may have restricted blood supply, as oxidative stress is a common feature of solid tumors. Recent studies have reported that enhanced expression of cytosolic superoxide dismutase (SOD1, a critical enzyme responsible for regulation of superoxide radicals, may increase the aggressive and invasive potential of malignant cells in some cancers. Methods: We used a variety of biochemical approaches and a prostate cancer cell line to study the effects of SOD1 on CXCR4 signaling. Results: Here, we report a direct interaction between SOD1 and CXCR4. We showed that SOD1 interacts directly with the first intracellular loop (ICL1 of CXCR4 and that the CXCL12/CXCR4-mediated regulation of AKT activation, apoptosis and cell migration in prostate cancer (PCa cells is differentially modulated under normal versus hypoxic conditions when SOD1 is present. Conclusions: This study highlights a potential new regulatory mechanism by which a sensor of the oxidative environment could directly regulate signal transduction of a receptor involved in cancer cell survival and migration.

  5. Lymphocyte Cc Chemokine Receptor 9 and Epithelial Thymus-Expressed Chemokine (Teck) Expression Distinguish the Small Intestinal Immune Compartment

    OpenAIRE

    2000-01-01

    The immune system has evolved specialized cellular and molecular mechanisms for targeting and regulating immune responses at epithelial surfaces. Here we show that small intestinal intraepithelial lymphocytes and lamina propria lymphocytes migrate to thymus-expressed chemokine (TECK). This attraction is mediated by CC chemokine receptor (CCR)9, a chemoattractant receptor expressed at high levels by essentially all CD4+ and CD8+ T lymphocytes in the small intestine. Only a small subset of lymp...

  6. Interleukin-8-mediated heterologous receptor internalization provides resistance to HIV-1 infectivity. Role of signal strength and receptor desensitization.

    Science.gov (United States)

    Richardson, Ricardo M; Tokunaga, Kenzo; Marjoram, Robin; Sata, Tetsutaro; Snyderman, Ralph

    2003-05-02

    Human immunodeficiency virus type 1 (HIV-1) entry into CD4(+) cells requires the chemokine receptors CCR5 or CXCR4 as co-fusion receptors. We have previously demonstrated that chemokine receptors are capable of cross-regulating the functions of each other and, thus, affecting cellular responsiveness at the site of infection. To investigate the effects of chemokine receptor cross-regulation in HIV-1 infection, monocytes and MAGIC5 and rat basophilic leukemia (RBL-2H3) cell lines co-expressing the interleukin-8 (IL-8 or CXCL8) receptor CXCR1 and either CCR5 (ACCR5) or CXCR4 (ACXCR4) were generated. IL-8 activation of CXCR1, but not the IL-8 receptor CXCR2, cross-phosphorylated CCR5 and CXCR4 and cross-desensitized their responsiveness to RANTES (regulated on activation normal T cell expressed and secreted) (CCL5) and stromal derived factor (SDF-1 or CXCL12), respectively. CXCR1 activation internalized CCR5 but not CXCR4 despite cross-phosphorylation of both. IL-8 pretreatment also inhibited CCR5- but not CXCR4-mediated virus entry into MAGIC5 cells. A tail-deleted mutant of CXCR1, DeltaCXCR1, produced greater signals upon activation (Ca(2+) mobilization and phosphoinositide hydrolysis) and cross-internalized CXCR4, inhibiting HIV-1 entry. The protein kinase C inhibitor staurosporine prevented phosphorylation and internalization of the receptors by CXCR1 activation. Taken together, these results indicate that chemokine receptor-mediated HIV-1 cell infection is blocked by receptor internalization but not desensitization alone. Thus, activation of chemokine receptors unrelated to CCR5 and CXCR4 may play a cross-regulatory role in the infection and propagation of HIV-1. Since DeltaCXCR1, but not CXCR1, cross-internalized and cross-inhibited HIV-1 infection to CXCR4, the data indicate the importance of the signal strength of a receptor and, as a consequence, protein kinase C activation in the suppression of HIV-1 infection by cross-receptor-mediated internalization.

  7. Elucidating the CXCL12/CXCR4 signaling network in chronic lymphocytic leukemia through phosphoproteomics analysis.

    Directory of Open Access Journals (Sweden)

    Morgan O'Hayre

    Full Text Available BACKGROUND: Chronic Lymphocytic Leukemia (CLL pathogenesis has been linked to the prolonged survival and/or apoptotic resistance of leukemic B cells in vivo, and is thought to be due to enhanced survival signaling responses to environmental factors that protect CLL cells from spontaneous and chemotherapy-induced death. Although normally associated with cell migration, the chemokine, CXCL12, is one of the factors known to support the survival of CLL cells. Thus, the signaling pathways activated by CXCL12 and its receptor, CXCR4, were investigated as components of these pathways and may represent targets that if inhibited, could render resistant CLL cells more susceptible to chemotherapy. METHODOLOGY/PRINCIPAL FINDINGS: To determine the downstream signaling targets that contribute to the survival effects of CXCL12 in CLL, we took a phosphoproteomics approach to identify and compare phosphopeptides in unstimulated and CXCL12-stimulated primary CLL cells. While some of the survival pathways activated by CXCL12 in CLL are known, including Akt and ERK1/2, this approach enabled the identification of additional signaling targets and novel phosphoproteins that could have implications in CLL disease and therapy. In addition to the phosphoproteomics results, we provide evidence from western blot validation that the tumor suppressor, programmed cell death factor 4 (PDCD4, is a previously unidentified phosphorylation target of CXCL12 signaling in all CLL cells probed. Additionally, heat shock protein 27 (HSP27, which mediates anti-apoptotic signaling and has previously been linked to chemotherapeutic resistance, was detected in a subset (approximately 25% of CLL patients cells examined. CONCLUSIONS/SIGNIFICANCE: Since PDCD4 and HSP27 have previously been associated with cancer and regulation of cell growth and apoptosis, these proteins may have novel implications in CLL cell survival and represent potential therapeutic targets. PDCD4 also represents a

  8. Putative cholesterol-binding sites in human immunodeficiency virus (HIV) coreceptors CXCR4 and CCR5.

    Science.gov (United States)

    Zhukovsky, Mikhail A; Lee, Po-Hsien; Ott, Albrecht; Helms, Volkhard

    2013-04-01

    Using molecular docking, we identified a cholesterol-binding site in the groove between transmembrane helices 1 and 7 near the inner membrane-water interface of the G protein-coupled receptor CXCR4, a coreceptor for HIV entry into cells. In this docking pose, the amino group of lysine K67 establishes a hydrogen bond with the hydroxyl group of cholesterol, whereas tyrosine Y302 stacks with cholesterol by its aromatic side chain, and a number of residues form hydrophobic contacts with cholesterol. Sequence alignment showed that a similar putative cholesterol-binding site is also present in CCR5, another HIV coreceptor. We suggest that the interaction of cholesterol with these putative cholesterol-binding sites in CXCR4 and CCR5 is responsible for the presence of these receptors in lipid rafts, for the effect of cholesterol on their conformational stability and function, and for the role that cell cholesterol plays in the cell entry of HIV strains that use these membrane proteins as coreceptors. We propose that mutations of residues that are involved in cholesterol binding will make CXCR4 and CCR5 insensitive to membrane cholesterol content. Cholesterol-binding sites in HIV coreceptors are potential targets for steroid drugs that bind to CXCR4 and CCR5 with higher binding affinity than cholesterol, but do not stabilize the native conformation of these proteins.

  9. The Role and Mechanism of CXCR4 and Its Ligand SDF-1 in the Development of Cervical Cancer Metastasis%CXCR4及其配体SDF-1在宫颈癌转移中的作用及其机制研究

    Institute of Scientific and Technical Information of China (English)

    沈晓燕; 王绍海; 梁铭霖; 汪宏波; 肖兰; 王泽华

    2008-01-01

    背景与目的:趋化凶子CXCR4[chemokine(C-X-C)receptor 4]受体及其配体基质细胞衍乍因子l(stromal cell dedved factor-1,SDF-1)可能与某些恶性肿瘤的迁移、侵袭和转移有关.本研究拟探讨CXCR4受体及其配体SDF-1(CXCR4/SDF-1轴)通过激活丝裂原活化蛋白激酶(mitogen-activated protein kinases,MAPK)信号通路在官颈癌转移中的作用及其机制.方法:采用激光共聚焦显微镜检测宫颈癌HeLa细胞内钙离子波动,Western blot法分析CXCR4/SDF-1对宫颈癌HeLa细胞中细胞外调节信号激酶(extracellular signal-regulated kinase,ERK)(包括ERK1和ERK2)磷酸化的影响;分别通过粘附实验、明胶酶谱法检测CXCR4/SDF-1对宫颈癌细胞粘附能力、基质金属蛋白酶(matrix metalloproteinase,MMP)分泌的影响.结果:SDF-1α与CXCR4相互结合后诱导了HeLa细胞胞内钙的迅速动员,其荧光强度(fluorescent intensity,FI)平均基础值与峰值差异有统计学意义(P<0.01);诱导了HeLa细胞ERK1/2快速磷酸化,作用后30min时磷酸化程度最强:增加了HeLa细胞粘附能力,不同浓度的SDF-1α与CXCR4结合后不同程度地增加了HeLa细胞粘附于纤维连接蛋白(fibronetin,FN)、层粘连蛋白(laminin,LN)的粘附细胞数,与对照组比较其差异均有统计学意义(P<0.05);加入ERK1/2信号通路抑制剂PD98059后,粘附于FN和LN的细胞数下降,与对照组相比差异有统计学意义(P<0.05);促进宫颈癌HeLa细胞分泌活性的MMP-2,这一作用随SDF-1α浓度升高而增强,SDF-1α在800 ng/mL浓度处分泌达高峰,以后开始下降.结论:CXCR4/SDF-1通过激活MAPK通路调控宫颈癌细胞的粘附能力,促进活性MMP-2分泌,进而参与宫颈癌侵袭和转移.

  10. Sequence similarity between the erythrocyte binding domain 1 of the Plasmodium vivax Duffy binding protein and the V3 loop of HIV-1 strain MN reveals binding residues for the Duffy Antigen Receptor for Chemokines

    Directory of Open Access Journals (Sweden)

    Garry Robert F

    2011-01-01

    Full Text Available Abstract Background The surface glycoprotein (SU, gp120 of the human immunodeficiency virus (HIV must bind to a chemokine receptor, CCR5 or CXCR4, to invade CD4+ cells. Plasmodium vivax uses the Duffy Binding Protein (DBP to bind the Duffy Antigen Receptor for Chemokines (DARC and invade reticulocytes. Results Variable loop 3 (V3 of HIV-1 SU and domain 1 of the Plasmodium vivax DBP share a sequence similarity. The site of amino acid sequence similarity was necessary, but not sufficient, for DARC binding and contained a consensus heparin binding site essential for DARC binding. Both HIV-1 and P. vivax can be blocked from binding to their chemokine receptors by the chemokine, RANTES and its analog AOP-RANTES. Site directed mutagenesis of the heparin binding motif in members of the DBP family, the P. knowlesi alpha, beta and gamma proteins abrogated their binding to erythrocytes. Positively charged residues within domain 1 are required for binding of P. vivax and P. knowlesi erythrocyte binding proteins. Conclusion A heparin binding site motif in members of the DBP family may form part of a conserved erythrocyte receptor binding pocket.

  11. The chemokine CXCL12 and the HIV-1 envelope protein gp120 regulate spontaneous activity of Cajal-Retzius cells in opposite directions.

    Science.gov (United States)

    Marchionni, Ivan; Beaumont, Michael; Maccaferri, Gianmaria

    2012-07-01

    Activation of the CXC chemokine receptor 4 (CXCR4) in Cajal–Retzius cells by CXC chemokine ligand 12 (CXCL12) is important for controlling their excitability. CXCR4 is also a co-receptor for the glycoprotein 120 (gp120) of the envelope of the human immunodeficiency virus type 1 (HIV-1), and binding of gp120 to CXCR4 may produce pathological effects. In order to study CXCR4-dependent modulation of membrane excitability, we recorded in cell-attached configuration spontaneous action currents from hippocampal stratum lacunosum-moleculare Cajal–Retzius cells of the CXCR4-EGFP mouse. CXCL12 (50 nM) powerfully inhibited firing independently of synaptic transmission, suggesting that CXCR4 regulates an intrinsic conductance. This effect was prevented by conditioning slices with BAPTA-AM (200 μM), and by blockers of the BK calcium-dependent potassium channels (TEA (1 mM), paxilline (10 μM) and iberiotoxin (100 nM)). In contrast, exposure to gp120 (pico- to nanomolar range, alone or in combination with soluble cluster of differentiation 4 (CD4)), enhanced spontaneous firing frequency. This effect was prevented by the CXCR4 antagonist AMD3100 (1 μM) and was absent in EGFP-negative stratum lacunosum-moleculare interneurons. Increased excitability was prevented by treating slices with BAPTA-AM or bumetanide, suggesting that gp120 activates a mechanism that is both calcium- and chloride-dependent. In conclusion, our results demonstrate that CXCL12 and gp120 modulate the excitability of Cajal–Retzius cells in opposite directions. We propose that CXCL12 and gp120 either generate calcium responses of different strength or activate distinct pools of intracellular calcium, leading to agonist-specific responses, mediated by BK channels in the case of CXCL12, and by a chloride-dependent mechanism in the case of gp120.

  12. Chemokines and Chemokine Receptors as Novel Therapeutic Targets in Rheumatoid Arthritis (RA): Inhibitory Effects of Traditional Chinese Medicinal Components

    Institute of Scientific and Technical Information of China (English)

    XinChen; JoostJ.Oppenheim; O.M.ZackHoward

    2004-01-01

    Chemokines belong to a large family of inflammatory cytokines responsible for migration and accumulation of leukocytes at inflammatory sites. Over the past decade, accumulating evidence indicated a crucial role for chemokines and chemokine receptors in the pathophysiology of rheumatoid arthritis (RA). RA is a chronic autoimmune disease in which the synovial tissue is heavily infiltrated by leukocytes. Chemokines play an important role in the infiltration, localization, retention of infiltrating leukocytes and generation of ectopic germinal centers in the inflamed synovium. Recent evidence also suggests that identification of inhibitors directly targeting chemokines or their receptors may provide a novel therapeutic strategy in RA. Traditional Chinese medicinals (TCMs) have a long history in the treatment of inflammatory joint disease. The basis forthe clinical benefits of TCM remains largely unclear. Our studies have led to the identification of numerousnovel chemokine/chemokine receptor inhibitors present in anti,inflammatory TCMs. All of these inhibitors were previously reported by other researchers to have anti-arthritic effect, which may be attributable, at leastin part, to their inhibitory effect on chemokine and/or chemokine receptor. Therefore, identification of agents capable of targeting chemokine/chemokine receptor interactions has suggested a mechanism of action for several TCM components and provided a means of identifying additional anti-RA TCM. Thus, this approach may lead to the discovery of new inhibitors of chemokines or chemokine receptors that can be used to treat diseases associated with inappropriately overactive chemokine mediated inflammatory reactions. Cellular & Molecular Immunology. 2004;1(5):336-342.

  13. CXCR4 Protein Epitope Mimetic Antagonist POL5551 Disrupts Metastasis and Enhances Chemotherapy Effect in Triple-Negative Breast Cancer.

    Science.gov (United States)

    Xiang, Jingyu; Hurchla, Michelle A; Fontana, Francesca; Su, Xinming; Amend, Sarah R; Esser, Alison K; Douglas, Garry J; Mudalagiriyappa, Chidananda; Luker, Kathryn E; Pluard, Timothy; Ademuyiwa, Foluso O; Romagnoli, Barbara; Tuffin, Gérald; Chevalier, Eric; Luker, Gary D; Bauer, Michael; Zimmermann, Johann; Aft, Rebecca L; Dembowsky, Klaus; Weilbaecher, Katherine N

    2015-11-01

    The SDF-1 receptor CXCR4 has been associated with early metastasis and poorer prognosis in breast cancers, especially the most aggressive triple-negative subtype. In line with previous reports, we found that tumoral CXCR4 expression in patients with locally advanced breast cancer was associated with increased metastases and rapid tumor progression. Moreover, high CXCR4 expression identified a group of bone marrow-disseminated tumor cells (DTC)-negative patients at high risk for metastasis and death. The protein epitope mimetic (PEM) POL5551, a novel CXCR4 antagonist, inhibited binding of SDF-1 to CXCR4, had no direct effects on tumor cell viability, but reduced migration of breast cancer cells in vitro. In two orthotopic models of triple-negative breast cancer, POL5551 had little inhibitory effect on primary tumor growth, but significantly reduced distant metastasis. When combined with eribulin, a chemotherapeutic microtubule inhibitor, POL5551 additively reduced metastasis and prolonged survival in mice after resection of the primary tumor compared with single-agent eribulin. Hypothesizing that POL5551 may mobilize tumor cells from their microenvironment and sensitize them to chemotherapy, we used a "chemotherapy framing" dosing strategy. When administered shortly before and after eribulin treatment, three doses of POL5551 with eribulin reduced bone and liver tumor burden more effectively than chemotherapy alone. These data suggest that sequenced administration of CXCR4 antagonists with cytotoxic chemotherapy synergize to reduce distant metastases. ©2015 American Association for Cancer Research.

  14. CXCR4, CXCL12 and the relative CXCL12-CXCR4 expression as prognostic factors in colon cancer.

    Science.gov (United States)

    Stanisavljević, Luka; Aßmus, Jörg; Storli, Kristian Eeg; Leh, Sabine Maria; Dahl, Olav; Myklebust, Mette Pernille

    2016-06-01

    The CXCL12-CXCR4 axis is proposed to mediate metastasis formation. In this study, we examined CXCL12, CXCR4 and the relative CXCL12-CXCR4 expression as prognostic factors in two cohorts of colon cancer patients. Immunohistochemistry (IHC) and in situ hybridization (ISH) were used to study CXCR4, CXCL12 and relative CXCL12-CXCR4 expression in tissue microarrays. Our study included totally 596 patients, 290 in cohort 1 and 306 in cohort 2. For tumour, node, metastasis (TNM) stage III, low nuclear expression of CXCR4 was a positive prognostic factor for 5-year disease-free survival (DFS) in cohort 1 (P = 0.007) and cohort 2 (P = 0.023). In multivariate analysis for stage III, nuclear expression of CXCR4 in cohort 1 was confirmed as a prognostic factor for DFS (hazard ratio (HR), 0.27; 95 % CI, 0.09 to 0.77). For TNM stage III, high cytoplasmic expression of CXCL12 was associated with better 5-year DFS in both cohorts (P = 0.006 and P = 0.006, respectively). We further validated the positive prognostic value of CXCL12 expression for 5-year DFS in stage III with ISH (P = 0.022). For TNM stage III, the relative CXCL12-CXCR4 expression (CXCL12 > CXCR4 vs CXCL12 = CXCR4 vs CXCL12 TNM stage III colon cancer.

  15. Complexity and dynamics of HIV-1 chemokine receptor usage in a multidrug-resistant adolescent.

    Science.gov (United States)

    Cavarelli, Mariangela; Mainetti, Lara; Pignataro, Angela Rosa; Bigoloni, Alba; Tolazzi, Monica; Galli, Andrea; Nozza, Silvia; Castagna, Antonella; Sampaolo, Michela; Boeri, Enzo; Scarlatti, Gabriella

    2014-12-01

    Maraviroc (MVC) is licensed in clinical practice for patients with R5 virus and virological failure; however, in anecdotal reports, dual/mixed viruses were also inhibited. We retrospectively evaluated the evolution of HIV-1 coreceptor tropism in plasma and peripheral blood mononuclear cells (PBMCs) of an infected adolescent with a CCR5/CXCR4 Trofile profile who experienced an important but temporary immunological and virological response during a 16-month period of MVC-based therapy. Coreceptor usage of biological viral clones isolated from PBMCs was investigated in U87.CD4 cells expressing wild-type or chimeric CCR5 and CXCR4. Plasma and PBMC-derived viral clones were sequenced to predict coreceptor tropism using the geno2pheno algorithm from the V3 envelope sequence and pol gene-resistant mutations. From start to 8.5 months of MVC treatment only R5X4 viral clones were observed, whereas at 16 months the phenotype enlarged to also include R5 and X4 clones. Chimeric receptor usage suggested the preferential usage of the CXCR4 coreceptor by the R5X4 biological clones. According to phenotypic data, R5 viruses were susceptible, whereas R5X4 and X4 viruses were resistant to RANTES and MVC in vitro. Clones at 16 months, but not at baseline, showed an amino acidic resistance pattern in protease and reverse transcription genes, which, however, did not drive their tropisms. The geno2pheno algorithm predicted at baseline R5 viruses in plasma, and from 5.5 months throughout follow-up only CXCR4-using viruses. An extended methodological approach is needed to unravel the complexity of the phenotype and variation of viruses resident in the different compartments of an infected individual. The accurate evaluation of the proportion of residual R5 viruses may guide therapeutic intervention in highly experienced patients with limited therapeutic options.

  16. Sequential administration of the high affinity CXCR4 antagonist BKT140 promotes megakaryopoiesis and platelet production.

    Science.gov (United States)

    Abraham, Michal; Weiss, Ido D; Wald, Hanna; Wald, Ori; Nagler, Arnon; Beider, Katia; Eizenberg, Orly; Peled, Amnon

    2013-10-01

    Platelets are the terminal differentiation product of megakaryocytes (MKs). Cytokines, such as thrombopoietin (TPO), are known to influence different steps in MK development; however, the complex differentiation and platelet localization processes are not fully understood. MKs express the receptor CXCR4 and have been shown to migrate in response to CXCL12 and to increase their platelet production. In this study, we studied the role of CXCR4 in platelet production with the high affinity CXCR4 antagonist, BKT140. Single and sequential administration of BKT140 significantly increased the number of MKs and haematopoietic progenitors (HPCs) within the bone marrow (BM). Increased megakaryopoiesis was associated with increased platelet production. Single and sequential administration of BKT140 also increased the number of HPCs in the blood. In a model of 5-fluorouracil-induced thrombocytopenia, BKT140 significantly reduced the severity and duration of thrombocytopenia and cytopenia when administered before and after chemotherapy. Our results demonstrated that the CXCR4 antagonist, BKT140, mediated unique beneficial effects by stimulating megakaryopoiesis and platelet production. These results provide evidence for the possible therapeutic use of BKT140 for modulating platelet numbers in thrombocytopenic conditions. © 2013 John Wiley & Sons Ltd.

  17. Natural killer cell activation and modulation of chemokine receptor profile in vitro by an extract from the cyanophyta Aphanizomenon flos-aquae.

    Science.gov (United States)

    Hart, Aaron N; Zaske, Lue Ann; Patterson, Kelly M; Drapeau, Christian; Jensen, Gitte S

    2007-09-01

    The present research was designed to study the effects of an extract from the edible cyanophyta Aphanizomenon flos-aquae on human natural killer (NK) cells. We have previously shown, using a double-blind randomized placebo-controlled crossover design, that ingestion of 1.5 g of dried whole A. flos-aquae resulted in a transient reduction in peripheral blood NK cells in 21 healthy human volunteers, suggesting increased NK cell homing into tissue. We have now identified an extract from A. flos-aquae (AFAe) that directly activates NK cells in vitro and modulates the chemokine receptor profile. NK cell activation was evaluated by expression of CD25 and CD69 on CD3-CD56+ cells after 18 hours. Changes in CXCR3 and CXCR4 chemokine receptor expression after 5-60 minutes were evaluated by immunostaining and flow cytometry. AFAe induced the expression of CD69 on CD3-CD56+ NK cells, induced CD25 expression on 25% of these cells, and acted in synergy with interleukin 2. NK cells enriched by RosetteSep (StemCell Technologies Inc., Vancouver, BC, Canada) were not activated by AFAe, indicating that the NK activation was dependent on other cells such as monocytes. The low-molecular-weight fraction <5,000 of AFAe was responsible for the most robust NK cell activation, suggesting novel compounds different from previously reported macrophage-activating large polysaccharides.

  18. Polymorphisms in chemokine and chemokine receptor genes and the development of coal workers' pneumoconiosis

    Energy Technology Data Exchange (ETDEWEB)

    Nadif, R.; Mintz, M.; Rivas-Fuentes, S.; Jedlicka, A.; Lavergne, E.; Rodero, M.; Kauffmann, F.; Combadiere, C.; Kleeberger, S.R. [INSERM, Villejuif (France)

    2006-02-07

    Chemokines and their receptors are key regulators of inflammation and may participate in the lung fibrotic process. Associations of polymorphisms in CCL5 (G-403A) and its receptor CCR5 {Delta}32), CCL2 (A-2578G) and CCR2 (V641), and CX3CR1 V2491 and T280M with coal worker's pneumoconiosis (CWP) were investigated in 209 miners examined in 1990, 1994 and 1999. Coal dust exposure was assessed by job history and ambient measures. The main health outcome was lung computed tomography (CT) score in 1990. Internal coherence was assessed by studying CT score in 1994, 4-year change in CT score, and CWP prevalence in 1999. CCR5 {Delta}32 carriers had significantly higher CT score in 1990 and 1994 (2.15 vs. 1.28, p = 0.01; 3.04 vs. 1.80, p = 0.04). The CX3CR1 1249 allele was significantly associated with lower 1990 CT score and lower progression in 4-year change in CT score in CCR5{Delta}32 carriers only (p for interaction = 0.03 and 0.02). CX3CR1 V2491 was associated with lower 1999 CWP prevalence (16.7%, 13.2%, 0.0% for VV, VI and II); the effect was most evident in miners with high dust exposure (31.6%, 21.7%, 0.0%). Our findings indicate that chemokine receptors CCR5 and CX3CR1 may be involved in the development of pneumoconiosis.

  19. Delayed functional expression of neuronal chemokine receptors following focal nerve demyelination in the rat: a mechanism for the development of chronic sensitization of peripheral nociceptors

    Directory of Open Access Journals (Sweden)

    Monahan Patrick E

    2007-12-01

    Full Text Available Abstract Background Animal and clinical studies have revealed that focal peripheral nerve axon demyelination is accompanied by nociceptive pain behavior. C-C and C-X-C chemokines and their receptors have been strongly implicated in demyelinating polyneuropathies and persistent pain syndromes. Herein, we studied the degree to which chronic nociceptive pain behavior is correlated with the neuronal expression of chemokines and their receptors following unilateral lysophosphatidylcholine (LPC-induced focal demyelination of the sciatic nerve in rats. Results Focal nerve demyelination increased behavioral reflex responsiveness to mechanical stimuli between postoperative day (POD 3 and POD28 in both the hindpaw ipsilateral and contralateral to the nerve injury. This behavior was accompanied by a bilateral increase in the numbers of primary sensory neurons expressing the chemokine receptors CCR2, CCR5, and CXCR4 by POD14, with no change in the pattern of CXCR3 expression. Significant increases in the numbers of neurons expressing the chemokines monocyte chemoattractant protein-1 (MCP-1/CCL2, Regulated on Activation, Normal T Expressed and Secreted (RANTES/CCL5 and interferon γ-inducing protein-10 (IP-10/CXCL10 were also evident following nerve injury, although neuronal expression pattern of stromal cell derived factor-1α (SDF1/CXCL12 did not change. Functional studies demonstrated that acutely dissociated sensory neurons derived from LPC-injured animals responded with increased [Ca2+]i following exposure to MCP-1, IP-10, SDF1 and RANTES on POD 14 and 28, but these responses were largely absent by POD35. On days 14 and 28, rats received either saline or a CCR2 receptor antagonist isomer (CCR2 RA-[R] or its inactive enantiomer (CCR2 RA-[S] by intraperitoneal (i.p. injection. CCR2 RA-[R] treatment of nerve-injured rats produced stereospecific bilateral reversal of tactile hyperalgesia. Conclusion These results suggest that the presence of chemokine

  20. CXCR4 is dispensable for T cell egress from chronically inflamed skin via the afferent lymph.

    Directory of Open Access Journals (Sweden)

    Skye A Geherin

    Full Text Available T cell recirculation through extralymphoid tissues is essential to immune surveillance, host defense and inflammation. In this process, T cells enter the tissue from the blood and subsequently leave via the afferent lymph. In the absence of inflammation, T cells require CCR7 expression to egress from the skin or lung, which is consistent with the constitutive expression of the CCR7 ligand CCL21 on lymphatic endothelium. However, during chronic inflammation alternative chemoattractants come into play, allowing Ccr7-deficient (Ccr7-/- T cells to egress efficiently from affected skin. As T cell egress from inflamed sites is a potential control point of the inflammatory response, we aimed to determine alternative T cell exit receptors using a mouse and a sheep model. We show that CCR7+ and CCR7- T cells exiting from the chronically inflamed skin were highly responsive to the CXCR4 ligand CXCL12, which was induced in the lymphatics in the inflamed site. Based on these findings, we hypothesized that CXCR4 mediates T cell egress from inflamed skin. However, pharmacological inhibition of CXCR4 did not affect the tissue egress of wildtype or Ccr7-/- CD4 and CD8 T cells after adoptive transfer into chronically inflamed skin. Similarly, adoptively transferred Cxcr4-/- Ccr7-/- and Ccr7-/- T cells egressed from the inflamed skin equally well. Based on these data, we conclude that, while CXCR4 might play an essential role for other cell types that enter the afferent lymphatics, it is dispensable for T cell egress from the chronically inflamed skin.

  1. Structure of CC Chemokine Receptor 5 with a Potent Chemokine Antagonist Reveals Mechanisms of Chemokine Recognition and Molecular Mimicry by HIV.

    Science.gov (United States)

    Zheng, Yi; Han, Gye Won; Abagyan, Ruben; Wu, Beili; Stevens, Raymond C; Cherezov, Vadim; Kufareva, Irina; Handel, Tracy M

    2017-06-20

    CCR5 is the primary chemokine receptor utilized by HIV to infect leukocytes, whereas CCR5 ligands inhibit infection by blocking CCR5 engagement with HIV gp120. To guide the design of improved therapeutics, we solved the structure of CCR5 in complex with chemokine antagonist [5P7]CCL5. Several structural features appeared to contribute to the anti-HIV potency of [5P7]CCL5, including the distinct chemokine orientation relative to the receptor, the near-complete occupancy of the receptor binding pocket, the dense network of intermolecular hydrogen bonds, and the similarity of binding determinants with the FDA-approved HIV inhibitor Maraviroc. Molecular modeling indicated that HIV gp120 mimicked the chemokine interaction with CCR5, providing an explanation for the ability of CCR5 to recognize diverse ligands and gp120 variants. Our findings reveal that structural plasticity facilitates receptor-chemokine specificity and enables exploitation by HIV, and provide insight into the design of small molecule and protein inhibitors for HIV and other CCR5-mediated diseases. Copyright © 2017 Elsevier Inc. All rights reserved.

  2. Structure of CC Chemokine Receptor 5 with a Potent Chemokine Antagonist Reveals Mechanisms of Chemokine Recognition and Molecular Mimicry by HIV

    Energy Technology Data Exchange (ETDEWEB)

    Zheng, Yi; Han, Gye Won; Abagyan, Ruben; Wu, Beili; Stevens, Raymond C.; Cherezov, Vadim; Kufareva, Irina; Handel, Tracy M. (USC); (Chinese Aca. Sci.); (UCSD)

    2017-06-01

    CCR5 is the primary chemokine receptor utilized by HIV to infect leukocytes, whereas CCR5 ligands inhibit infection by blocking CCR5 engagement with HIV gp120. To guide the design of improved therapeutics, we solved the structure of CCR5 in complex with chemokine antagonist [5P7]CCL5. Several structural features appeared to contribute to the anti-HIV potency of [5P7]CCL5, including the distinct chemokine orientation relative to the receptor, the near-complete occupancy of the receptor binding pocket, the dense network of intermolecular hydrogen bonds, and the similarity of binding determinants with the FDA-approved HIV inhibitor Maraviroc. Molecular modeling indicated that HIV gp120 mimicked the chemokine interaction with CCR5, providing an explanation for the ability of CCR5 to recognize diverse ligands and gp120 variants. Our findings reveal that structural plasticity facilitates receptor-chemokine specificity and enables exploitation by HIV, and provide insight into the design of small molecule and protein inhibitors for HIV and other CCR5-mediated diseases.

  3. The SDF1-CXCR4 Axis Functions through p38-MAPK Signaling to Drive Breast Cancer Progression and Metastasis

    Science.gov (United States)

    2008-09-01

    Highway, Suite 1204, Arlington, VA 22202- 4302. Respondents should be aware that notwithstanding any other provision of law, no person shall be subject...cancer, chemokine, SDF-1, MSC 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF ABSTRACT 18. NUMBER OF PAGES 19a. NAME OF RESPONSIBLE PERSON ...D.M., Foda , H.D., Zucker, S. CXCR4 and CXCL12(SDF-1) in prostate cancer: inhibitory effects of human single chain Fv antibodies. Clinical Cancer

  4. Tumorigenesis induced by the HHV8-encoded chemokine receptor requires ligand modulation of high constitutive activity

    DEFF Research Database (Denmark)

    Holst, P J; Rosenkilde, M M; Manfra, D;

    2001-01-01

    ORF74 (or KSHV-vGPCR) is a highly constitutively active G protein-coupled receptor encoded by HHV8 that is regulated both positively and negatively by endogenous chemokines. When expressed in transgenic mice, this chemokine receptor induces an angioproliferative disease closely resembling Kaposi...... sarcoma (KS). Here we demonstrate that several lines of mice carrying mutated receptors deficient in either constitutive activity or chemokine regulation fail to develop KS-like disease. In addition, animals expressing a receptor that preserves chemokine binding and constitutive activity but that does...

  5. Role of stromal cell derived factor-1/CXC chemokine receptor 4 pathway in mesenchymal stem cells therapies in the management of diabetic retinopathy%基质细胞衍生因子-1/CXC趋化因子受体4通路在间充质干细胞治疗糖尿病视网膜病变中的作用研究

    Institute of Scientific and Technical Information of China (English)

    王健; 陈松

    2016-01-01

    Mesenchymal stem cells (MSC) are considered to have important value in the treatment of various diseases because of their low immunogenicity,transferability,and strong tissue repair capacity.Stromal cell derived factor-1 (SDF-1) and its receptor CXC chemokine receptor 4 (CXCR4) pathway plays an important role in migration of MSC.The induction of homing of MSC to retina by regulating SDF-1/CXCR4 may exert the curative effect on diabetic retinopathy to greatest exent.%间充质干细胞(MSC)具有低免疫原性、可移植性、组织修复能力强等特征,对于包括糖尿病在内的多种疾病的治疗具有重要的研究价值.在MSC治疗应用研究中,细胞归巢以及向特定的目标细胞转化是其关键.基质细胞衍生因子-1(SDF-1)及其受体CXC趋化因子受体4(CXCR4)组成的SDF-1/CXCR4通路在MSC迁移中具有重要作用,通过调控SDF-1/CXCR4通路诱导MSC归巢至视网膜分化为特定的视网膜神经元治疗糖尿病视网膜病变为糖尿病视网膜病变治疗提供了一条全新的路径.

  6. The bovine chemokine receptors and their mRNA abundance in mononuclear phagocytes

    Directory of Open Access Journals (Sweden)

    Ashley George

    2010-07-01

    Full Text Available Abstract Background The chemokine and chemokine receptor families play critical roles in both the healthy and diseased organism mediating the migration of cells. The chemokine system is complex in that multiple chemokines can bind to one chemokine receptor and vice versa. Although chemokine receptors have been well characterised in humans, the chemokine receptor repertoire of cattle is not well characterised and many sequences are yet to be experimentally validated. Results We have identified and sequenced bovine homologs to all identified functional human chemokine receptors. The bovine chemokine receptors show high levels of similarity to their human counterparts and similar genome arrangements. We have also characterised an additional bovine chemokine receptor, not present in the available genome sequence of humans or the more closely related pigs or horses. This receptor shows the highest level of similarity to CCR1 but shows significant differences in regions of the protein that are likely to be involved in ligand binding and signalling. We have also examined the mRNA abundance levels of all identified bovine chemokine receptors in mononuclear phagocytic cells. Considerable differences were observed in the mRNA abundance levels of the receptors, and interestingly the identified novel chemokine receptor showed differing levels of mRNA abundance to its closest homolog CCR1. The chemokine receptor repertoire was shown to differ between monocytes, macrophages and dendritic cells. This may reflect the differing roles of these cells in the immune response and may have functional consequences for the trafficking of these cells in vivo. Conclusions In summary, we have provided the first characterisation of the complete bovine chemokine receptor gene repertoire including a gene that is potentially unique to cattle. Further study of this receptor and its ligands may reveal a specific role of this receptor in cattle. The availability of the bovine

  7. SDF-1/CXCR4轴与髓外白血病%SDF-1/CXCR4 Axis and Extramedullary Leukemia

    Institute of Scientific and Technical Information of China (English)

    章大谦; 吴广胜

    2009-01-01

    基质细胞衍生因子1(SDF-1)及其受体CXCR4所构成的SDF-1/CXCR4轴生物效应的研究近些年来进展迅速,其在肿瘤发生及发展中起重要作用,并与髓外白血病密切相关.本文就SDF-1及其受体CXCR4在白血病细胞中的表达,SDF-1/CXCR4轴与髓外自血病的关系的研究进展加以综述.

  8. Role of chemokine receptors and intestinal epithelial cells in the mucosal inflammation and tolerance.

    Science.gov (United States)

    Kulkarni, Neeraja; Pathak, Manisha; Lal, Girdhari

    2017-02-01

    The intestinal epithelial lining is a very dynamic interface, where multiple interactions occur with the external world. The intestinal epithelial barrier is continuously exposed to a huge load of commensal microorganisms, food-borne antigens, as well as invading enteropathogens. Intestinal epithelial cells (IECs) and underlying immune cells are the main players in maintaining the delicate balance between gut tolerance and inflammation. IECs deferentially express the variety of chemokines and chemokine receptors, and these receptor-ligand interactions not only mediate the infiltration and activation of immune cells but also switch on the survival cascades in IECs. In this review, we discussed how chemokine-chemokine receptor-induced interactions play a central role to coordinate the interplay between IECs and gut immune cells to maintain homeostasis or elicit gut inflammation. Furthermore, we discussed how chemokines and chemokine receptors were used as a target for developing new drugs and therapies to control gut inflammation and autoimmunity. © Society for Leukocyte Biology.

  9. RNase P-Associated External Guide Sequence Effectively Reduces the Expression of Human CC-Chemokine Receptor 5 and Inhibits the Infection of Human Immunodeficiency Virus 1

    Directory of Open Access Journals (Sweden)

    Wenbo Zeng

    2013-01-01

    Full Text Available External guide sequences (EGSs represent a new class of RNA-based gene-targeting agents, consist of a sequence complementary to a target mRNA, and render the target RNA susceptible to degradation by ribonuclease P (RNase P. In this study, EGSs were constructed to target the mRNA encoding human CC-chemokine receptor 5 (CCR5, one of the primary coreceptors for HIV. An EGS RNA, C1, efficiently directed human RNase P to cleave the CCR5 mRNA sequence in vitro. A reduction of about 70% in the expression level of both CCR5 mRNA and protein and an inhibition of more than 50-fold in HIV (R5 strain Ba-L p24 production were observed in cells that expressed C1. In comparison, a reduction of about 10% in the expression of CCR5 and viral growth was found in cells that either did not express the EGS or produced a “disabled” EGS which carried nucleotide mutations that precluded RNase P recognition. Furthermore, the same C1-expressing cells that were protected from R5 strain Ba-L retained susceptibility to X4 strain IIIB, which uses CXCR4 as the coreceptor instead of CCR5, suggesting that the RNase P-mediated cleavage induced by the EGS is specific for the target CCR5 but not the closely related CXCR4. Our results provide direct evidence that EGS RNAs against CCR5 are effective and specific in blocking HIV infection and growth. These results also demonstrate the feasibility to develop highly effective EGSs for anti-HIV therapy.

  10. Allosteric and orthosteric sites in CC chemokine receptor (CCR5), a chimeric receptor approach

    DEFF Research Database (Denmark)

    Thiele, Stefanie; Steen, Anne; Jensen, Pia C;

    2011-01-01

    molecules often act more deeply in an allosteric mode. However, opposed to the well described molecular interaction of allosteric modulators in class C 7-transmembrane helix (7TM) receptors, the interaction in class A, to which the chemokine receptors belong, is more sparsely described. Using the CCR5...... chemokine receptor as a model system, we studied the molecular interaction and conformational interchange required for proper action of various orthosteric chemokines and allosteric small molecules, including the well known CCR5 antagonists TAK-779, SCH-C, and aplaviroc, and four novel CCR5 ago......-allosteric molecules. A chimera was successfully constructed between CCR5 and the closely related CCR2 by transferring all extracellular regions of CCR2 to CCR5, i.e. a Trojan horse that resembles CCR2 extracellularly but signals through a CCR5 transmembrane unit. The chimera bound CCR2 (CCL2 and CCL7), but not CCR5...

  11. Effects and Significance of SDF-1/CXCR4 in Proliferation, Migration and Invasion of Colorectal Cancer Cell Line SW480%SDF-1/CXCR4对大肠癌细胞株SW480增殖、迁移及侵袭的影响及意义

    Institute of Scientific and Technical Information of China (English)

    袁丽倩; 郑淑芳

    2014-01-01

    目的:探讨基质细胞衍生因子-1(SDF-1)及其特异性受体CXC趋化因子受体4(CXCR4)对大肠癌细胞SW480增殖、迁移及侵袭能力的影响及意义。方法取对数生长期大肠癌细胞SW480分为对照组(未经任何处理)、SDF-1组(加入100μg/L SDF-1)、SDF-1+AMD3100混合组(向细胞中加入1 mg/L AMD3100,孵育2 h后加入100μg/L SDF-1)、AMD3100组(加入1 mg/L AMD3100)。免疫组化法检测SW480细胞中CXCR4蛋白表达情况;RT-PCR法检测SW480细胞中CXCR4 mRNA的表达情况,以及外源性SDF-1和AMD3100作用后CXCR4 mRNA表达水平的变化;MTT增殖实验、Transwell迁移及侵袭实验分别检测SDF-1以及AMD3100对SW480细胞增殖、迁移及侵袭能力的影响。结果 SW480细胞中CXCR4蛋白呈阳性表达(阳性率80%)。SW480细胞中有CXCR4 mRNA的表达,100μg/L SDF-1促使CXCR4 mRNA表达水平进一步上调,且能被1 mg/L AMD3100阻断。SDF-1组细胞增殖活性(0.847±0.039)高于对照组(0.624±0.011)和SDF-1+AMD3100混合组(0.607±0.016),AMD3100组(0.456±0.032)低于对照组和SDF-1+AMD3100混合组(F=108.030,P<0.05)。Transwell小室迁移及侵袭实验中SDF-1组穿膜细胞数(个:98.7±5.8、33.7±6.2)均多于对照组(21.0±2.2、6.1±2.3)、SDF-1+AMD3100混合组(18.5±8.4、8.5±2.8)和AMD3100组(12.1±3.2、2.1±1.0),后3组间比较差异无统计学意义。结论 SDF-1/CXCR4生物轴可促进大肠癌细胞SW480的增殖、迁移及侵袭。%Objective To discuss the influence and significance of stromal cell-derived factor 1 (SDF-1) and its specific receptor CXC chemokine receptor 4 (CXCR4) in proliferation, migration and invasion ability of SW480 colorectal cancer cells. Methods The colorectal cancer cell line SW480 in logarithmic phase was divided into four groups:control group (with no any processing), SDF-1 group (added 100μg/L SDF-1), SDF-1+1 mg/L AMD3100 mixed group (added 1 mg/L AMD3100 for 2 hours, then added 100

  12. CXCR4 antibody treatment suppresses metastatic spread to the lung of intratibial human osteosarcoma xenografts in mice.

    Science.gov (United States)

    Brennecke, Patrick; Arlt, Matthias J E; Campanile, Carmen; Husmann, Knut; Gvozdenovic, Ana; Apuzzo, Tiziana; Thelen, Marcus; Born, Walter; Fuchs, Bruno

    2014-03-01

    Current combined surgical and neo-adjuvant chemotherapy of primary metastatic osteosarcoma (OS) is ineffective, reflected by a 5-year survival rate of affected patients of less than 20 %. Studies in experimental OS metastasis models pointed to the CXCR4/CXCL12 homing axis as a novel target for OS metastasis-suppressive treatment. The present study investigated for the first time the CXCR4-blocking principle in a spontaneously metastasizing human 143B OS cell line-derived orthotopic xenograft mouse model. The highly metastatic 143B cells, unlike the parental non-metastatic HOS cells, express functional CXCR4 receptors at the cell surface, as revealed in this study by RT/PCR of gene transcripts, by FACS analysis with the monoclonal anti CXCR4 antibody 12G5 (mAb 12G5) and by CXCL12 time- and dose-dependent stimulation of AKT and ERK phosphorylation. A significantly (p lung metastasis. Repetitive treatment of mice with 143B cell-derived intratibial tumors given intravenous bolus injections of mAb12G5 indeed inhibited significantly (p lung micrometastases of lacZ-transduced 143B cells. Antibody treatment had also a mild inhibitory effect on primary tumor growth associated with remarkably less osteolysis, but it did not affect the number of developing lung macrometastases. In conclusion, these results demonstrate considerable potential of high-affinity CXCR4-blocking agents for OS tumor cell homing suppressive treatment in metastasizing OS complementary to current (neo)-adjuvant chemotherapy.

  13. Enhanced unique pattern of hematopoietic cell mobilization induced by the CXCR4 antagonist 4F-benzoyl-TN14003.

    Science.gov (United States)

    Abraham, Michal; Biyder, Katia; Begin, Michal; Wald, Hanna; Weiss, Ido D; Galun, Eithan; Nagler, Arnon; Peled, Amnon

    2007-09-01

    An increase in the number of stem cells in blood following mobilization is required to enhance engraftment after high-dose chemotherapy and improve transplantation outcome. Therefore, an approach that improves stem cell mobilization is essential. The interaction between CXCL12 and its receptor, CXCR4, is involved in the retention of stem cells in the bone marrow. Therefore, blocking CXCR4 may result in mobilization of hematopoietic progenitor and stem cells. We have found that the CXCR4 antagonist known as 4F-benzoyl-TN14003 (T-140) can induce mobilization of hematopoietic stem cells and progenitors within a few hours post-treatment in a dose-dependent manner. Furthermore, although T-140 can also increase the number of white blood cells (WBC) in blood, including monocytes, B cells, and T cells, it had no effect on mobilizing natural killer cells. T-140 was found to efficiently synergize with granulocyte colony-stimulating factor (G-CSF) in its ability to mobilize WBC and progenitors, as well as to induce a 660-fold increase in the number of erythroblasts in peripheral blood. Comparison between the CXCR4 antagonists T-140 and AMD3100 showed that T-140 with or without G-CSF was significantly more potent in its ability to mobilize hematopoietic stem cells and progenitors into blood. These results demonstrate that different CXCR4 antagonists may have different therapeutic potentials.

  14. Duffy antigen receptor for chemokines mediates chemokine endocytosis through a macropinocytosis-like process in endothelial cells.

    Directory of Open Access Journals (Sweden)

    Yani Zhao

    Full Text Available The Duffy antigen receptor for chemokines (DARC shows high affinity binding to multiple inflammatory CC and CXC chemokines and is expressed by erythrocytes and endothelial cells. Recent evidence suggests that endothelial DARC facilitates chemokine transcytosis to promote neutrophil recruitment. However, the mechanism of chemokine endocytosis by DARC remains unclear.We investigated the role of several endocytic pathways in DARC-mediated ligand internalization. Here we report that, although DARC co-localizes with caveolin-1 in endothelial cells, caveolin-1 is dispensable for DARC-mediated (125I-CXCL1 endocytosis as knockdown of caveolin-1 failed to inhibit ligand internalization. (125I-CXCL1 endocytosis by DARC was also independent of clathrin and flotillin-1 but required cholesterol and was, in part, inhibited by silencing Dynamin II expression.(125I-CXCL1 endocytosis was inhibited by amiloride, cytochalasin D, and the PKC inhibitor Gö6976 whereas Platelet Derived Growth Factor (PDGF enhanced ligand internalization through DARC. The majority of DARC-ligand interactions occurred on the endothelial surface, with DARC identified along plasma membrane extensions with the appearance of ruffles, supporting the concept that DARC provides a high affinity scaffolding function for surface retention of chemokines on endothelial cells.These results show DARC-mediated chemokine endocytosis occurs through a macropinocytosis-like process in endothelial cells and caveolin-1 is dispensable for CXCL1 internalization.

  15. The chemokine receptor CCR5 Δ32 allele in natalizumab-treated multiple sclerosis

    DEFF Research Database (Denmark)

    Møller, M; Søndergaard, H B; Koch-Henriksen, N;

    2014-01-01

    The chemokine receptor CCR5 may be important for the recruitment of pathogenic T cells to the CNS in multiple sclerosis (MS). We hypothesized that this chemokine receptor might still be important for T-cell migration during treatment with anti-very late antigen (VLA)-4 antibody. We therefore anal...

  16. Ubiquitylation of the chemokine receptor CCR7 enables efficient receptor recycling and cell migration

    OpenAIRE

    Schäuble, Karin; Hauser, Mark A.; Rippl, Alexandra; Bruderer, Roland; Otero, Carolina; Gröttrup, Marcus; Legler, Daniel F.

    2012-01-01

    The chemokine receptor CCR7 is essential for lymphocyte and dendritic cell homing to secondary lymphoid organs. Owing to the ability to induce directional migration, CCR7 and its ligands CCL19 and CCL21 are pivotal for the regulation of the immune system. Here, we identify a novel function for receptor ubiquitylation in the regulation of the trafficking process of this G-protein-coupled seven transmembrane receptor. We discovered that CCR7 is ubiquitylated in a constitutive, ligand-independen...

  17. Transfection of CXCR-4 using microbubble-mediated ultrasound irradiation and liposomes improves the migratory ability of bone marrow stromal cells.

    Science.gov (United States)

    Wang, Gong; Zhuo, Zhongxiong; Zhang, Qian; Xu, Yali; Wu, Shengzheng; Li, Lu; Xia, Hongmei; Gao, Yunhua

    2015-01-01

    Bone marrow stromal cells (BMSCs) have proven useful for the treatment of various human diseases and injuries. However, their reparative capacity is limited by their poor migration and homing ability, which are primarily dependent on the SDF-1/CXCR4 axis. Most subcultured BMSCs lack CXCR4 receptor expression on the cell surface and exhibit impaired migratory capacity. To increase responsiveness to SDF-1 and promote cell migration and survival of cultured BMSCs, we used a combination of ultrasound-targeted microbubble destruction (UTMD) and liposomes to increase CXCR4 expression in vitro. We isolated and cultured rat BMSCs to their third passage and transduced them with recombinant plasmid pDsRed-CXCR4 using microbubble-mediated ultrasound irradiation and liposomes. Compared to some viral vectors, the method we employed here resulted in significantly better transfection efficiency, CXCR4 expression, and technical reproducibility. The benefits of this approach are likely due to the combination of "sonoporation" caused by shockwaves and microjet flow resulting from UTMD-generated cavitation. Following transfection, we performed a transwell migration assay and found that the migration ability of CXCR4-modified BMSCs was 9-fold higher than controls. The methods we describe here provide an effective, safe, non-viral means to achieve high levels of CXCR4 expression. This is associated with enhanced migration of subcultured BMSCs and may be useful for clinical application as well.

  18. Suicide gene reveals the myocardial neovascularization role of mesenchymal stem cells overexpressing CXCR4 (MSC(CXCR4.

    Directory of Open Access Journals (Sweden)

    Jialiang Liang

    Full Text Available BACKGROUND: Our previous studies indicated that MSC(CXCR4 improved cardiac function after myocardial infarction (MI. This study was aimed to investigate the specific role of MSC(CXCR4 in neovascularization of infarcted myocardium using a suicide gene approach. METHODS: MSCs were transduced with either lentivirus-null vector/GFP (MSC(Null as control or vector encoding for overexpressing CXCR4/GFP. The MSC derived-endothelial cell (EC differentiation was assessed by a tube formation assay, Dil-ac-LDL uptake, EC marker expression, and VE-cadherin promoter activity assay. Gene expression was analyzed by quantitative RT-PCR or Western blot. The suicide gene approach was under the control of VE-cadherin promoter. In vivo studies: Cell patches containing MSC(Null or MSC(CXCR4 were transduced with suicide gene and implanted into the myocardium of MI rat. Rats received either ganciclovir (GCV or vehicle after cell implantation. After one month, the cardiac functional changes and neovascularization were assessed by echocardiography, histological analysis, and micro-CT imaging. RESULTS: The expression of VEGF-A and HIF-1α was significantly higher in MSC(CXCR4 as compared to MSC(Null under hypoxia. Additionally, MSC(CXCR4 enhanced new vessel formation and EC differentiation, as well as STAT3 phosphorylation under hypoxia. STAT3 participated in the transcription of VE-cadherin in MSC(CXCR4 under hypoxia, which was inhibited by WP1066 (a STAT3 inhibitor. In addition, GCV specifically induced death of ECs with suicide gene activation. In vivo studies: MSC(CXCR4 implantation promoted cardiac functional restoration, reduced infarct size, improved cardiac remodeling, and enhanced neovascularization in ischemic heart tissue. New vessels derived from MSC(CXCR4 were observed at the injured heart margins and communicated with native coronary arteries. However, the derived vessel networks were reduced by GCV, reversing improvement of cardiac function. CONCLUSION: The

  19. In vivo TCR signaling in CD4+ T cells imprints a cell-intrinsic, transient low motility pattern independent of chemokine receptor expression levels or microtubular network, integrin and protein kinase C activity

    Directory of Open Access Journals (Sweden)

    Markus eAckerknecht

    2015-06-01

    Full Text Available Intravital imaging has revealed that T cells change their migratory behavior during physiological activation inside lymphoid tissue. Yet, it remains less well investigated how the intrinsic migratory capacity of activated T cells is regulated by chemokine receptor levels or other regulatory elements. Here, we used an adjuvant-driven inflammation model to examine how motility patterns corresponded with CCR7, CXCR4 and CXCR5 expression levels on OVA-specific DO11.10 CD4+ T cells in draining lymph nodes. We found that while CCR7 and CXCR4 surface levels remained essentially unaltered during the first 48-72 h after activation of CD4+ T cells, their in vitro chemokinetic and directed migratory capacity to the respective ligands CCL19, CCL21 and CXCL12 was substantially reduced during this time window. Activated T cells recovered from this temporary decrease in motility on day 6 post immunization, coinciding with increased migration to the CXCR5 ligand CXCL13. The transiently impaired CD4+ T cell motility pattern correlated with increased LFA-1 expression and augmented phosphorylation of the microtubule regulator Stathmin on day 3 post immunization, yet neither microtubule destabilization nor integrin blocking could reverse TCR-imprinted unresponsiveness. Furthermore, protein kinase C (PKC inhibition did not restore chemotactic activity, ruling out PKC-mediated receptor desensitization as mechanism for reduced migration in activated T cells. Thus, we identify a cell-intrinsic, chemokine receptor level-uncoupled decrease in motility in CD4+ T cells shortly after activation, coinciding with clonal expansion. The transiently reduced ability to react to chemokinetic and chemotactic stimuli may contribute to the sequestering of activated CD4+ T cells in reactive PLNs, allowing for integration of costimulatory signals required for full activation.

  20. Chemokine receptor expression by inflammatory T cells in EAE.

    Science.gov (United States)

    Mony, Jyothi Thyagabhavan; Khorooshi, Reza; Owens, Trevor

    2014-01-01

    Chemokines direct cellular infiltration to tissues, and their receptors and signaling pathways represent targets for therapy in diseases such as multiple sclerosis (MS). The chemokine CCL20 is expressed in choroid plexus, a site of entry of T cells to the central nervous system (CNS). The CCL20 receptor CCR6 has been reported to be selectively expressed by CD4(+) T cells that produce the cytokine IL-17 (Th17 cells). Th17 cells and interferon-gamma (IFNγ)-producing Th1 cells are implicated in induction of MS and its animal model experimental autoimmune encephalomyelitis (EAE). We have assessed whether CCR6 identifies specific inflammatory T cell subsets in EAE. Our approach was to induce EAE, and then examine chemokine receptor expression by cytokine-producing T cells sorted from CNS at peak disease. About 7% of CNS-infiltrating CD4(+) T cells produced IFNγ in flow cytometric cytokine assays, whereas less than 1% produced IL-17. About 1% of CD4(+) T cells produced both cytokines. CCR6 was expressed by Th1, Th1+17 and by Th17 cells, but not by CD8(+) T cells. CD8(+) T cells expressed CXCR3, which was also expressed by CD4(+) T cells, with no correlation to cytokine profile. Messenger RNA for IFNγ, IL-17A, and the Th1 and Th17-associated transcription factors T-bet and RORγt was detected in both CCR6(+) and CXCR3(+) CD4(+) T cells. IFNγ, but not IL-17A mRNA expression was detected in CD8(+) T cells in CNS. CCR6 and CD4 were co-localized in spinal cord infiltrates by double immunofluorescence. Consistent with flow cytometry data some but not all CD4(+) T cells expressed CCR6 within infiltrates. CD4-negative CCR6(+) cells included macrophage/microglial cells. Thus we have for the first time directly studied CD4(+) and CD8(+) T cells in the CNS of mice with peak EAE, and determined IFNγ and IL17 expression by cells expressing CCR6 and CXCR3. We show that neither CCR6 or CXCR3 align with CD4 T cell subsets, and Th1 or mixed Th1+17 predominate in EAE.

  1. Expression of specific chemokines and chemokine receptors in the central nervous system of multiple sclerosis patients

    DEFF Research Database (Denmark)

    Sørensen, Torben Lykke; Tani, M; Jensen, J

    1999-01-01

    Chemokines direct tissue invasion by specific leukocyte populations. Thus, chemokines may play a role in multiple sclerosis (MS), an idiopathic disorder in which the central nervous system (CNS) inflammatory reaction is largely restricted to mononuclear phagocytes and T cells. We asked whether sp...

  2. Role and clinicopathologic significance of CXC chemokine ligand 16 and chemokine (C-X-C motif) receptor 6 expression in gastric carcinomas.

    Science.gov (United States)

    Xing, Ya-nan; Xu, Xiao-yan; Nie, Xia