284 research outputs found
The proangiogenic capacity of polymorphonuclear neutrophils delineated by microarray technique and by measurement of neovascularization in wounded skin of CD18-deficient mice
Growing evidence supports the concept that polymorphonuclear neutrophils (PMN) are critically involved in inflammation-mediated angiogenesis which is important for wound healing and repair. We employed an oligonucleotide microarray technique to gain further insight into the molecular mechanisms underlying the proangiogenic potential of human PMN. In addition to 18 known angiogenesis-relevant genes, we detected the expression of 10 novel genes, namely midkine, erb-B2, ets-1, transforming growth factor receptor-beta(2) and -beta(3), thrombospondin, tissue inhibitor of metalloproteinase 2, ephrin A2, ephrin B2 and restin in human PMN freshly isolated from the circulation. Gene expression was confi rmed by the RT-PCR technique. In vivo evidence for the role of PMN in neovascularization was provided by studying neovascularization in a skin model of wound healing using CD18-deficient mice which lack PMN infi ltration to sites of lesion. In CD18-deficient animals, neo- vascularization was found to be signifi cantly compromised when compared with wild- type control animals which showed profound neovascularization within the granulation tissue during the wound healing process. Thus, PMN infiltration seems to facilitate inflammation mediated angiogenesis which may be a consequence of the broad spectrum of proangiogenic factors expressed by these cells. Copyright (c) 2006 S. Karger AG, Basel
Expression of CXCL10 is associated with response to radiotherapy and overall survival in squamous cell carcinoma of the tongue
Five-year survival for patients with oral cancer has been disappointingly stable during the last decades, creating a demand for new biomarkers and treatment targets. Lately, much focus has been set on immunomodulation as a possible treatment or an adjuvant increasing sensitivity to conventional treatments. The objective of this study was to evaluate the prognostic importance of response to radiotherapy in tongue carcinoma patients as well as the expression of the CXC-chemokines in correlation to radiation response in the same group of tumours. Thirty-eight patients with tongue carcinoma that had received radiotherapy followed by surgery were included. The prognostic impact of pathological response to radiotherapy, N-status, T-stage, age and gender was evaluated using Cox's regression models, Kaplan-Meier survival curves and chi-square test. The expression of 23 CXC-chemokine ligands and their receptors were evaluated in all patients using microarray and qPCR and correlated with response to treatment using logistic regression. Pathological response to radiotherapy was independently associated to overall survival with a 2-year survival probability of 81 % for patients showing a complete pathological response, while patients with a non-complete response only had a probability of 42 % to survive for 2 years (p = 0.016). The expression of one CXC-chemokine, CXCL10, was significantly associated with response to radiotherapy and the group of patients with the highest CXCL10 expression responded, especially poorly (p = 0.01). CXCL10 is a potential marker for response to radiotherapy and overall survival in patients with squamous cell carcinoma of the tongue
Interleukin-8/CXCL8 is a growth factor for human lung cancer cells
Interleukin-8/CXCL8 (IL-8) is a chemokine and angiogenic factor. Recently, IL-8 was identified as an autocrine growth factor in several human cancers. Here, we investigated the expression and function of IL-8 in lung cancer cells. The expressions of IL-8 and its receptors, CXCR1 and CXCR2, were examined in a panel of non-small cell lung cancer (NSCLC) and small cell lung cancer (SCLC) cell lines. Using reverse transcription–polymerase chain reaction (RT–PCR) and enzyme-linked immunosorbent assay, we found that all NSCLC cell lines tested produced modest or high levels of IL-8 (up to 51 ng ml−1 106 cells−1). Expression of CXCR1 and CXCR2 was found by RT–PCR and flow cytometry in two out of three cell lines. In contrast, SCLC cell lines produced very low or undetectable levels of IL-8, but expressed CXCR1 and CXCR2. We next investigated whether IL-8 could act as an autocrine growth factor in two NSCLC cell lines (H460 and MOR/P) expressing both IL-8 and its receptors. We found that cell proliferation was attenuated by anti-IL-8 neutralising antibody to 71 and 76% in H460 and MOR/P, respectively (P<0.05). Exogenous IL-8 significantly stimulated cell proliferation in four SCLC cell lines tested in a dose-dependent fashion. Cell proliferation was increased by between 18% (P<0.05) and 37% (P<0.05). Stimulation of cell proliferation by IL-8 was also demonstrated by analysis of proliferating cell nuclear antigen expression and cell cycle in H69 cells. Furthermore, we investigated which receptor(s) mediated the mitogenic function of IL-8 in lung cancer cells. We found that cell proliferation was significantly reduced by anti-CXCR1 antibody but not by anti-CXCR2 antibody. In conclusion, IL-8 can act as an autocrine and/or paracrine growth factor for lung cancer cells, and the mitogenic function of IL-8 in lung cancer is mediated mainly by CXCR1 receptor
An IP-10 (CXCL10)-derived peptide inhibits angiogenesis
Angiogenesis plays a critical role in processes such as organ development, wound healing, and tumor growth. It requires well-orchestrated integration of soluble and matrix factors and timely recognition of such signals to regulate this process. Previous work has shown that newly forming vessels express the chemokine receptor CXC receptor 3 (CXCR3) and, activation by its ligand IP-10 (CXCL10), both inhibits development of new vasculature and causes regression of newly formed vessels. To identify and develop new therapeutic agents to limit or reverse pathological angiogenesis, we identified a 21 amino acid fragment of IP-10, spanning the α-helical domain residues 77-98, that mimic the actions of the whole IP-10 molecule on endothelial cells. Treatment of the endothelial cells with the 22 amino acid fragment referred to as IP-10p significantly inhibited VEGF-induced endothelial motility and tube formation in vitro, properties critical for angiogenesis. Using a Matrigel plug assay in vivo, we demonstrate that IP-10p both prevented vessel formation and induced involution of nascent vessels. CXCR3 neutralizing antibody was able to block the inhibitory effects of the IP-10p, demonstrating specificity of the peptide. Inhibition of endothelial function by IP-10p was similar to that described for IP-10, secondary to CXCR3-mediated increase in cAMP production, activation of PKA inhibiting cell migration, and inhibition of VEGF-mediated m-calpain activation. IP-10p provides a novel therapeutic agent that inhibits endothelial cell function thus, allowing for the modulation of angiogenesis. © 2012 Yates-Binder et al
Oestradiol enhances tumour regression induced by B7-1/IL-2 adenoviral gene transfer in a murine model of breast cancer
Chemokine receptor expression in tumour islets and stroma in non-small cell lung cancer
<p>Abstract</p> <p>Background</p> <p>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.</p> <p>Methods</p> <p>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.</p> <p>Results</p> <p>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 <0.001, respectively) as well as stromal CXCR3 density (p = 0.003). There was a positive correlation between macrophage density and CXCR3 expression (r<sub>s </sub>= 0.520, p = 0.02) and between mast cell density and CXCR3 expression (r<sub>s </sub>= 0.499, p = 0.03) in the tumour islets.</p> <p>Conclusion</p> <p>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.</p
Expression of amphiregulin predicts poor outcome in patients with pancreatic ductal adenocarcinoma
The establishment of the Standard Cosmological Model through observations
Over the last decades, observations with increasing quality have
revolutionized our understanding of the general properties of the Universe.
Questions posed for millenia by mankind about the origin, evolution and
structure of the cosmos have found an answer. This has been possible mainly
thanks to observations of the Cosmic Microwave Background, of the large-scale
distribution of matter structure in the local Universe, and of type Ia
supernovae that have revealed the accelerated expansion of the Universe. All
these observations have successfully converged into the so-called "concordance
model". In spite of all these observational successes, there are still some
important open problems, the most obvious of which are what generated the
initial matter inhomogeneities that led to the structure observable in today's
Universe, and what is the nature of dark matter, and of the dark energy that
drives the accelerated expansion. In this chapter I will expand on the previous
aspects. I will present a general description of the Standard Cosmological
Model of the Universe, with special emphasis on the most recent observations
that have us allowed to consolidate this model. I will also discuss the
shortfalls of this model, its most pressing open questions, and will briefly
describe the observational programmes that are being planned to tackle these
issues.Comment: Accepted for publication in the book "Reviews in Frontiers of Modern
Astrophysics: From Space Debris to Cosmology" (eds Kabath, Jones and Skarka;
publisher Springer Nature) funded by the European Union Erasmus+ Strategic
Partnership grant "Per Aspera Ad Astra Simul" 2017-1-CZ01-KA203-03556
Overexpression of the duffy antigen receptor for chemokines (DARC) by NSCLC tumor cells results in increased tumor necrosis
BACKGROUND: The Duffy antigen receptor for chemokines (DARC) is known to be a promiscuous chemokine receptor that binds a variety of CXC and CC chemokines in the absence of any detectable signal transduction events. Within the CXC group of chemokines, DARC binds the angiogenic CXC chemokines including IL-8 (CXCL8), GROα (CXCL1) and ENA-78 (CXCL5), all of which have previously been shown to be important in non-small cell lung carcinoma (NSCLC) tumor growth. We hypothesized that overexpression of DARC by a NSCLC tumor cell line would result in the binding of the angiogenic ELR+ CXC chemokines by the tumor cells themselves, and thus interfere with the stimulation of endothelial cells and induction of angiogenesis by the tumor cell-derived angiogenic chemokines. RESULTS: NSCLC tumor cells that constitutively expressed DARC were generated and their growth characteristics were compared to control transfected cells in vitro and in vivo in SCID animals. We found that tumors derived from DARC-expressing cells were significantly larger in size than tumors derived from control-transfected cells. However, upon histological examination we found that DARC-expressing tumors had significantly more necrosis and decreased tumor cellularity, as compared to control tumors. Expression of DARC by NSCLC cells was also associated with a decrease in tumor-associated vasculature and a reduction in metastatic potential. CONCLUSIONS: The expression of DARC in the context of NSCLC tumors may act as a chemokine decoy receptor and interferes with normal tumor growth and chemokine-induced tumor neovascularization
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