胃癌组织中CXCL12、CXCR4的表达及意义

目的 探讨胃癌组织中趋化因子CXCL12及其受体CXCR4蛋白表达与肿瘤浸润、转移的关系.方法 选择胃癌患者50例,取其癌组织和癌旁正常组织标本,应用免疫组化SP方法,检测CXCL12及CXCR4在胃癌组织、正常黏膜及转移淋巴结中的表达情况.结果 与正常黏膜相比,CXCL12和CXCR4在胃癌组织中的表达升高(P＜0.01),胃癌有淋巴结转移者较无淋巴结转移者表达升高(P＜0.01).结论 胃癌组织中CXCL12与CXCR4的高表达与胃癌的浸润及淋巴结转移有关;CXCL12和CXCR4检测可作为判断胃癌预后的一项指标.     

Persistent CXCR4 expression after preoperative chemoradiotherapy predicts early recurrence and poor prognosis in esophageal cancer

INTRODUCTIONThe migration of tumor cells to a secondary site from their primary location is a crucial issue in cancer metastasis. Recently, a novel “homing” signaling mechanism has been proposed, in which target organs produce and release specific chemo…     

基质细胞衍生因子-1/趋化因子受体CXCR4轴与支气管哮喘

基质细胞衍生因子-1（stromal cell—derived factor-1,SDF-1）是趋化因子亚家族的成员之一,SDF1与趋化因子受体CXCR4（CXCR4）作用,构成SDF-1／CXCR4反应轴,在介导造血干细胞迁移及归巢、恶性肿瘤浸润转移、HIV感染、胚胎发育、免疫与炎症反应等方面发挥着重要作用。SDF1／CXCR4通过调节炎症细胞、血管形成、气道高反应性（AHR）等方面参与支气管哮喘（哮喘）的发生发展。     

The CXCR4 chemokine receptor in acute and chronic leukaemia: a marrow homing receptor and potential therapeutic target

Chemokine (C-X-C motif) receptor 4 (CXCR4) is essential for homing and maintenance of haematopoietic stem cells in distinct stromal cell niches within the marrow. Chemotactic responsiveness of haematopoietic stem cells is restricted to the ligand for CXCR4, stromal cell-derived factor-1 (SDF-1/CXCL12), which is constitutively secreted by marrow stromal cells. Myeloid and lymphoid leukaemia cells also express CXCR4 that induces leukaemia cell chemotaxis and migration beneath marrow stromal cells. CXCR4 expression levels have a major prognostic impact in acute myeloid leukaemia. There is growing in vitro and in vivo evidence that CXCR4 expression by leukaemia cells allows for homing and their retention within the marrow. As such, leukaemia cells appear to utilise CXCR4 to access niches that are normally restricted to progenitor cells, and thereby reside in a microenvironment that favours their growth and survival. CXCR4- and integrin-mediated contact between leukaemia cells and stromal cells protects leukaemia cells from spontaneous and chemotherapy-induced cell death and therefore may represent a mechanism to explain minimal residual disease and subsequent relapses commonly seen in the treatment of these diseases. This review summarises our current knowledge regarding the importance of CXCR4 in acute and chronic leukaemia, discusses the importance of CXCR4 detection by flow cytometry in the diagnostic workup of leukaemia patients, and introduces the potential role of CXCR4-targeting compounds for the treatment of leukaemia patients.     

CXCR4/SDF-1 axis is involved in lymph node metastasis of gastric carcinoma

AIM:To investigate the role of CXC chemokine receptor-4 (CXCR4) and stromal cell-derived factor-1 (SDF-1) in lymph node metastasis of gastric carcinoma.METHODS:In 40 cases of gastric cancer,expression of CXCR4 mRNA in cancer and normal mucous membrane and SDF-1 mRNA in lymph nodes around the stomach was detected using quantitative polymerase chain reaction (PCR) (TaqMan) and immunohistochemistric assay.SGC-7901 and MGC80-3 cancer cells were used to investigate the effect of SDF-1 on cell proliferation and m...     

CXCR4 promotes differentiation of oligodendrocyte progenitors and remyelination

Multiple sclerosis is a neurodegenerative disease characterized by episodes of autoimmune attack of oligodendrocytes leading to demyelination and progressive functional deficits. Because many patients exhibit functional recovery in between demyelinating episodes, understanding mechanisms responsible for repair of damaged myelin is critical for developing therapies that promote remyelination and prevent disease progression. The chemokine CXCL12 is a developmental molecule known to orchestrate the migration, proliferation, and differentiation of neuronal precursor cells within the developing CNS. Although studies suggest a role for CXCL12 in oligodendroglia ontogeny in vitro, no studies have investigated the role of CXCL12 in remyelination in vivo in the adult CNS. Using an experimental murine model of demyelination mediated by the copper chelator cuprizone, we evaluated the expression of CXCL12 and its receptor, CXCR4, within the demyelinating and remyelinating corpus callosum (CC). CXCL12 was significantly up-regulated within activated astrocytes and microglia in the CC during demyelination, as were numbers of CXCR4+NG2+ oligodendrocyte precursor cells (OPCs). Loss of CXCR4 signaling via either pharmacological blockade or in vivo RNA silencing led to decreased OPCs maturation and failure to remyelinate. These data indicate that CXCR4 activation, by promoting the differentiation of OPCs into oligodendrocytes, is critical for remyelination of the injured adult CNS.     

外周血SDF-1/CXCR4轴与急性心肌梗死患者冠状动脉侧支循环形成的关系

目的 检测急性心肌梗死(acute myocardial infarction,AMI)患者外周血基质细胞衍生因子-1(stromalcell derived factor 1,SDF-1)、CXC趋化因子受体-4(C-X-C chemokine receptor 4,CXCR4)的浓度,探讨两者在AMI患者冠状动脉侧...     

Chemokine receptor expression on infiltrating lymphocytes from abdominal aortic aneurysms: role of CXCR4-CXCL12 in lymphoid recruitment

This is a study to define the profile of chemokine receptors expressed on isolated infiltrating lymphocytes in human abdominal aortic aneurysms (AAAs), and to examine their role in lymphoid recruitment. AAA T-lymphocytes were CXCR4-positive, CCR7-negative and partially CXCR3 and CCR5-positive. Functionally, AAA T-cells were proinflammatory effector cells, as they produced IFN-γ and granzyme A. AAA B-lymphocytes were CXCR4-positive and exhibited low CXCR5 expression. A relevant feature of infiltrating T- and B-lymphocytes was the high intensity of CXCR4 expression and the capability to migrate to CXCL12. CXCL12-producing cells were found in the adventitia of AAA. These cells were CD45-negative and partially VCAM-1 and DR-positive. In summary, the present results suggest that CXCR4, expressed on infiltrating lymphocytes, and CXCL12, expressed on stromal cells, is involved in the recruitment of lymphocytes within the arterial wall in AAA.     

CXCR4/CXCL12与胃癌生物学行为

胃癌是一种常见恶性肿瘤,总体疗效欠佳,尤其发生腹膜转移者,预后较差.近年来,CXCR4及CXCL12在肿瘤研究中已逐渐成为热点;在胃癌研究中已逐渐见相关报道,如在胃癌生长、迁徙、转移和肿瘤新生血管形成等诸方面均起着重要作用.CXCR4受体拮抗剂在胃癌动物模型中的治疗效果也显示了其应用前景.此文综述了CXCR4/CXCL12在胃癌中作用机制,对CXCR4/CXCL12的深入研究将有望使其成为胃癌靶向治疗的特异靶点.     

基质细胞衍生因子-1/CXCR4轴与肝脏疾病

基质细胞衍生因子-1(SDF-1)/CXCR4轴及其介导的细胞信号转导通路在肝脏疾病中的作用是国内外研究的热点.研究发现SDF-1/ CXCR4信号转导途径与肝脏再生、炎症、肝硬化以及肿瘤等疾病有关,但其具体机制尚未完全清楚.在细胞微环境中,SDF-1/CXCR4相互作用促进肝癌细胞生长,增强肿瘤的迁移、浸润以及转移能力.本文就SDF-1/CXCR4通路在肝再生、炎症、肿瘤疾病中的病理特征和致病机制的研究进展作一综述.     

Characterization of the CXCR4 signaling in pancreatic cancer cells

CXCL12 and its receptor, CXCR4, are emerging as promising targets for modulating growth, angiogenesis, and metastasis in several human cancers. Indeed, blocking the receptor is sufficient to prevent metastasis and angiogenesis in experimental breast cancer xenografts. Recently, the biological effect of the CXCR4 in pancreatic cancer, one of the most deadly neoplastic diseases, has been reported. However, the molecular mechanism by which CXCR4 contributes to these properties is not completely understood. In this paper, we characterize the signaling pathways activated by CXCR4 in pancreatic cancer. We show that after CXCR4 activation, EGFR becomes tyrosine phosphorylated, and the kinase activity of this receptor, together with the activation of MMPs, Src, and PI3-Kinase, is required for CXCR4-mediated ERK activation. Analysis of this cascade in pancreatic cancer cells revealed that the ERK-mediated pathway regulates genes involved in angiogenesis, such as VEGF, CD44, HIF1α, and IL-8. Furthermore, ERK blockage inhibits the migration and tube formation of endothelial cells induced by CXCL12. Considering that inhibitors for several components of this pathway, including CXCR4 itself, are at different stages of clinical trials, this study provides theoretical justification for the clinical testing of these drugs in pancreatic cancer, thus extending the list of potential targets for treating this dismal disease.     

The expression of chemokine receptor CXCR3: relevance to disease activity of rheumatoid arthritis

 CXC chemokine receptor 3 (CXCR3) is selectively expressed on T helper 1 (Th1) type T cells and has been shown to be responsible for Th1-dominant immune responses. In this study, we analyzed the expression of CXCR3 on peripheral blood T lymphocytes of patients with rheumatoid arthritis (RA) by FACS analysis using antihuman CXCR3 monoclonal antibody and determined the clinical relevance in this disease. Significantly higher expression of CXCR3 was found on peripheral blood CD4+ T lymphocytes of RA patients than healthy controls. The CXCR3 expression in RA patients with a high erythrocyte sedimentation rate was significantly higher than in those with a low erythrocyte sedimentation rate. Moreover, we found that the CXCR3 expression in RA patients with long-term disease duration was significantly higher than in those with short-term disease. On the other hand, CC chemokine receptor 4 (CCR4), which was shown to be selectively expressed on Th2-type T cells, was expressed at low levels in RA patients as well as in healthy controls. The serum level of interleukin (IL)-18 in RA patients was higher than that in healthy controls, although there was no statistically significant difference. This study suggests that the Th1 immune response is predominant in RA and that CXCR3 may have relevance in regard to the disease course in RA patients. Received: January 28, 2002 / Accepted: August 14, 2002     

CXCR4 antagonism increases T cell trafficking in the central nervous system and improves survival from West Nile virus encephalitis

The migration of lymphocytes into the CNS during viral encephalitis is hindered by the blood-brain barrier (BBB) such that most infiltrating cells remain localized to perivascular spaces. This sequestration of leukocytes away from the parenchyma is believed to protect the CNS from immunopathologic injury. Infections of the CNS with highly cytopathic neurotropic viruses, such as West Nile virus (WNV), however, require the parenchymal penetration of T lymphocytes for virus clearance and survival, suggesting that perivascular localization might hinder antiviral immune responses during WNV encephalitis. Using human and murine brain specimens from individuals with WNV encephalitis, we evaluated the expression of CXCL12 and its receptor, CXCR4, at the BBB and tested the hypothesis that inhibition of CXCR4 would promote T lymphocyte entry into the CNS parenchyma and increase viral clearance. Antagonism of CXCR4 significantly improved survival from lethal infection through enhanced intraparenchymal migration of WNV-specific CD8(+) T cells within the brain, leading to reduced viral loads and, surprisingly, decreased immunopathology at this site. The benefits of enhanced CD8(+) T cell infiltration suggest that pharmacologic targeting of CXCR4 may have therapeutic utility for the treatment of acute viral infections of the CNS.     

电针联合脂肪源性干细胞移植对脑缺血/再灌注大鼠SDF-1和CXCR4表达的影响

目的探讨电针联合脂肪源性干细胞(ADSC)移植对大鼠缺血/再灌注损伤后趋化因子SDF-1及其受体CXCR4的影响。方法成年大鼠随机分为模型组、电针组、ADSC移植组、电针+ADSC组。线栓法制作大鼠大脑中动脉缺血(MCAO)2h再灌注模型,电针组取大椎穴和内关穴行电针治疗。ADSC组尾静脉注射PKH26标记的ADSC细胞悬液,电针+ADSC组联合电针和AD-SC移植治疗。缺血7d后行神经功能损害评分(NSS),采用Western bolt法及实时荧光定量PCR检测海马区SDF-1、CXCR4蛋白和mRNA表达。结果电针+ADSC组海马区PKH-26标记的细胞个数高于ADSC组(P<0.05)。与模型组比较,电针组、ADSC组和电针+ADSC组NSS评分均显著降低,海马区SDF-1、CXCR4蛋白和mRNA表达增加(P<0.05)。其中电针+ADSC组较电针组和ADSC组NSS评分显著降低,而SDF-1、CXCR4蛋白和mRNA表达显著增加(P<0.05)。结论电针联合脂肪源性干细胞移植促进脑缺血再灌注大鼠神经功能恢复作用优于单独治疗组,其机制可能与电针上调脑海马区SDF-1和CXCR4表达,促进移植的ADSC迁移和存活有关。     

沉默CXCR4基因对食管鳞癌EC-9706细胞中MMP-9基因表达的影响

目的:探讨在食管鳞癌EC-9706细胞中沉默CXCR4基因对MMP-9基因表达的影响,为阐明CXCR4基因在食管鳞癌侵袭转移中的作用提供实验依据.方法:化学合成2条靶向CXCR4基因的siRNA1和siRNA2,同时设立荧光标记阴性对照和空白对照.脂质体法转染入EC-9706细胞,荧光显微镜下观察转染效率.转染48h后,半定量RT-PCR检测各组细胞CXCR4和MMP-9基因mRNA表达的变化,Western blot检测各组细胞CXCR4和MMP-9基因蛋白表达的变化,侵袭小室检测各组细胞穿膜细胞数的变化,MTT检测各组细胞的A值.结果:与阴性对照和空白对照相比,转染CXCR4siRNA1和siRNA2组细胞CXCR4mRNA和蛋白的表达明显降低,差异具有统计学意义(P<0.05);同时与阴性对照和空白对照相比,转染CXCR4siRNA1和siRNA2组细胞MMP-9mRNA和蛋白的表达同样明显降低,差异具有统计学意义(P<0.05);转染CXCR4siRNA1和siRNA2组细胞穿膜细胞数与阴性对照和空白对照相比明显下降,差异具有统计学意义(P<0.05);MTT结果显示转染CXCR4siRNA1和siR...     

CXCR4 modulates contractility in adult cardiac myocytes

The inflammatory response is critical to the development and progression of heart failure. Chemokines and their receptors are a distinct class of inflammatory modulators that may play a role in mediating myocardial dysfunction in heart failure. Levels of the chemokine CXCL12, also known as stromal cell-derived factor (SDF), and its receptor, CXCR4, are elevated in patients with heart failure, and we undertook this study to determine whether this chemokine system can directly affect cardiac function in the absence of leukocytes. Murine papillary muscles and adult rat cardiac myocytes treated with CXCL12, the only identified ligand of CXCR4, demonstrate blunted inotropic responses to physiologic concentrations of calcium. The negative inotropic effects on cardiac myocytes are accompanied by a proportional diminution of calcium transients. The effects are abrogated by AMD3100, a specific CXCR4 inhibitor. Overexpression of the receptor through adenoviral infection with a CXCR4 construct accentuates the negative inotropic effects of CXCL12 on cardiac myocytes during calcium stimulation. CXCR4 activation also attenuates beta-adrenergic-mediated increases in calcium mobilization and fractional shortening in cardiac myocytes. In electrophysiologic studies, CXCL12 decreases forskolin- and isoproterenol-induced voltage-gated L-type calcium channel activation. These studies demonstrate that activation of CXCR4 results in a direct negative inotropic modulation of cardiac myocyte function. The specific mechanism of action involves alterations of calcium channel activity on the membrane. The presence of functional CXCR4 on cardiac myocytes introduces a new target for treating cardiac dysfunction.