间质细胞衍生因子1及其受体CXCR4在浸润性乳腺癌中的表达及其临床意义

目的 研究间质细胞衍生因子1(SDF-1)及其受体CXCR4在浸润性乳腺癌中的表达,并分析其与浸润性乳腺癌相关临床病理指标及淋巴结转移之间的关系.方法 采用免疫组织化学LSAB方法检测SDF-1/CXCR4在120例浸润性乳腺癌中的表达情况;采用地高辛标记的寡核苷酸探针进行原位杂交以检测趋化因子SDF-1在肿瘤环境中表达的部位及来源.结果 (1)SDF-1主要表达于肿瘤细胞的胞质和胞膜;SDF-1的胞质表达在淋巴结阳性组高于阴性组(P=0.033),且其表达程度与淋巴结受累数目、病理学分期、组织学分级、肿瘤大小及ER表达等指标呈正相关(P<0.05);(2)罕见SDF-1 mRNA表达的脉管内皮却可见SDF-1蛋白的表达,其表达程度与肿瘤胞质SDF-1着色正相关(P<0.01);且淋巴管内皮SDF-1的着色与淋巴结转移程度为正相关(P=0.005);血管内皮SDF-1的着色与肿瘤环境中的淋巴细胞浸润正相关(P<0.01),且同时伴有较多淋巴细胞浸润及SDF-1血管内皮着色阳性的病例,其淋巴结的转移程度分别高于仅有上述条件之一或二者均不具备的各组病例(P<0.05);(3)CXCR4也主要表达于肿瘤细胞的胞质和胞核;CXCR4的胞质表达在淋巴结阳性组高于阴性组(P<0.05),且其表达程度与淋巴结受累数目、病理学分期、组织学分级、肿瘤大小及HER2表达等呈正相关(P=0.005),而胞核的表达仅与PR的表达情况呈正相关(P<0.01);(4)瘤细胞质CXCR4与SDF-1的表达呈正相关(P=0.001).结论 浸润性乳腺癌肿瘤细胞SDF-1和CXCR4的表达与多项临床病理指标,尤其是淋巴结转移率及转移程度有关,可作为预测乳腺癌淋巴结转移及预后的免疫病理学指标,同时应注意肿瘤微环境中SDF-1的多个来源及定位的不同意义.     

胃癌中SDF-1、CXCR4、MMP-2和MMP-9的表达及意义

目的研究趋化因子SDF-1及其受体CXCR4以及MMP-2和MMP-9在胃癌中的表达,探讨SDF-1对MMP-2和MMP-9表达的影响。方法应用免疫组化EnVision两步法检测109例胃癌组织中SDF-1、CXCR4、MMP-2和MMP-9的表达。结果 (1)SDF-1、CXCR4、MMP-2、MMP-9在胃癌组的表达阳性率分别为88.1%、56.9%、80.7%和83.4%,高于切缘对照组的47.8%、30.4%、43.4%和47.8%,差异有显著性(P<0.05);(2)SDF-1和CXCR4的表达在淋巴结转移组高于无转移组(P<0.05),SDF-1、MMP-9表达程度与淋巴结转移、组织学分级、浆膜侵犯、临床分期指标呈正相关(P<0.05);MMP-2、CXCR4表达程度与淋巴结转移、浆膜侵犯、临床分期呈正相关(P<0.05);(3)SDF-1与其受体CXCR4的表达及与MMP-2、MMP-9均呈正相关(P<0.05)。结论 (1)SDF-1、CXCR4、MMP-2和MMP-9的表达水平与胃癌的发生、侵袭及淋巴结转移密切相关,可作为预测胃癌淋巴结转移及预后的指标;(2)SDF-1/CXCR4轴可通过加强肿瘤细胞MMP-2和MMP-9分泌的途径促进肿瘤的浸润和转移,提示SDF-1可能是药物靶向治疗的重要靶点。     

SDF-1/CXCR4及VEGF在结直肠腺癌中的表达及其意义

目的:研究VEGF、SDF-1及CXCR4在结直肠腺癌中的表达及其与临床病理学参数之间的相关性;探讨SDF-1/CXCR4轴与VEGF在结直肠腺癌发生发展浸润转移中的作用。方法:利用实时荧光定量PCR(RT-q PCR)法及免疫组织化学SP法检测80例结直肠腺癌及其对应癌旁组织中SDF-1、CXCR4和VEGF mRNA及蛋白的表达。结果:在mRNA水平上,结直肠癌组中SDF-1、CXCR4、VEGF的表达显著高于对应的癌旁组织。免疫组化结果显示,肿瘤中c蛋白表达阳性率分别为78.7%、60%和66.3%高于对应癌旁组织的37.5%、42.5%和28.8%,差异显著(P0.05);结直肠癌中SDF-1表达水平与肿瘤细胞淋巴结转移、远处转移及TNM分期密切相关(P0.05),与患者的年龄、性别、肿瘤的大小、浸润深度等无关;CXCR4的表达与患者的淋巴结转移及TNM分期密切相关;SDF-1的表达与CXCR4及VEGF的表达成显著正相关。结论:SDF-1/CXCR4及VEGF在结直肠癌组织中高表达,并且与肿瘤生物学行为密切相关,提示其在肿瘤的发生发展浸润转移过程中发挥重要作用。     

趋化因子受体CXCR4在人肺癌高转移细胞株的表达和意义

目的：以人肺癌高、低转移细胞株95D、95C为研究对象，研究趋化因子受体CXCR4的表达及其在肿瘤细胞体外转移潜能中的作用和意义。方法：采用RT-PCR检测95D、95C细胞CXCR4 mRNA的表达情况；以PMA活化肿瘤细胞，研究CXCR4 mRNA表达水平与细胞活性状态的关系；应用钙离子内流实验验证其表达是否具有功能；通过趋化实验观察CXCR4特异性配件SDF-α和裸鼠组织匀浆液对95D细胞的趋化迁移作用；通过MTT法测定95D细胞对SDF-1α作用的增殖反应。结果：95D细胞功能性地高表达趋化因子受体CXCR4，且其表达水平与细胞活性状态有关；CXCR4特异性配件SDF-1α和裸鼠肺、淋巴结组织匀浆均可在体外趋化95D细胞的迁移，SDF-1α还可促进95D细胞的增殖。结论：95D细胞功能性高表达趋化因子受体CXCR4可能与人肺癌细胞株95D的体外高转移潜能有关。     

HER2 interacts with CD44 to up-regulate CXCR4 via epigenetic silencing of microRNA-139 in gastric cancer cells

人表皮生长因子受体家族分子HER2(erbB2/neu)在包括乳腺癌、胃癌在内的多种肿瘤细胞表面特异表达,并与肿瘤的转移和预后不良密切相关。作为生长因子受体,HER2信号促进肿瘤生长和增殖的机制多有报道。趋化因子SDF-1及其受体CXCR4是介导肿     

大肠癌中SDF-1与CXCR4的表达及临床意义

目的观察基质细胞衍生因子1(stromal cell-derived factor 1,SDF-1)及其受体CXCR4蛋白和mRNA在大肠腺癌、大肠管状腺瘤、非肿瘤性大肠黏膜组织中的表达,探讨二者在大肠腺癌的发生、发展、浸润转移中的作用。方法采用免疫组化SP两步法和RT-PCR法检测上述3组中SDF-1和CXCR4蛋白、mRNA的表达。结果 (1)免疫组化SP两步法检测SDF-1、CX-CR4的蛋白在非肿瘤性大肠黏膜、大肠管状腺瘤、大肠腺癌中的阳性表达量呈明显递增,组间差异均有统计学意义(P<0.05);(2)RT-PCR检测SDF-1和CXCR4的mRNA在大肠腺癌组中的表达高于非肿瘤性大肠黏膜组(P<0.01);(3)大肠腺癌组SDF-1、CXCR4的蛋白与mRNA的表达均与癌组织的浸润深度、淋巴结转移有关(P<0.05,P<0.01);(4)大肠腺癌组织中SDF-1和CXCR4二者间的蛋白、mRNA表达均呈正相关(r=0.436,P<0.01;r=0.949,P<0.01)。结论 SDF-1和CXCR4在大肠腺癌组织中高表达,可能与大肠腺癌的发生、浸润、转移密切相关。     

SDF-1/CXCR4生物学轴与肿瘤关系的研究进展

趋化因子SDF-1,又称CXCL12,PBSF,与其特异性受体CXCR4广泛表达在多种组织和器官上,它们所构成的SDF-1/CXCR4 生物学轴在多种肿瘤的发生,发展以及转移中都发挥重要作用,其可能是通过MAPK,AKT通路发挥作用。对这一特殊生物学轴的研究可能为肿瘤防治找到新的突破口。     

趋化因子SDF-1α及其受体介导涎腺腺样囊性癌细胞的趋化与侵袭

探讨趋化因子SDF-1α及其受体CXCR4对涎腺腺样囊性癌细胞趋化与侵袭活性的促进作用。采用RT-PCR法检测涎腺腺样囊性癌肺高、低转移细胞株ACC-M和ACC-2中CXCR4 mRNA的表达;Boyden趋化小室法检测在SDF-1α作用下ACC-M细胞和ACC-2细胞的趋化与侵袭活性;检测CXCR4 mAb对ACC-M细胞和ACC-2细胞趋化活性和侵袭活性的抑制作用。结果显示:2株涎腺腺样囊性癌细胞中均存在不同程度CXCR4 mRNA的表达,其在肺高转移细胞株ACC-M中的表达显著高于肺低转移细胞株ACC-2;SDF-1α对2种细胞均具有趋化活性和侵袭活性,且对ACC-M细胞的趋化活性和侵袭活性显著强于ACC-2细胞;CXCR4 mAb能够抑制涎腺腺样囊性癌细胞的这种趋化活性和侵袭活性。趋化因子SDF-1α及其受体CXCR4能够介导涎腺腺样囊性癌细胞的趋化与侵袭。     

细胞内趋化因子重组突变体SDF-1α/54/KDEL的构建及其对CXCR4受体在细胞膜表面表达的抑制作用

构建人基质细胞衍生因子(SDF-1)突变体SDF-1α/54/KDEL重组真核表达质粒,并考察其对T细胞性白血病细胞株Molt-4细胞表面受体CXCR4表达的影响,为尝试表型敲除肿瘤细胞CXCR4以抑制肿瘤的转移提供理论和实验依据.以SDF-WT-Gly×4-Dec/PET30a( )质粒为模板,用PCR法扩增出SDF-1α/54并将其亚克隆至真核表达质粒pEGFP-C3构建成真核表达载体pEGFP-C3/SDF-1α/54/KDEL.经酶切及测序验证后,脂质体介导转染入COS-7细胞,通过Western blot检测SDF-1α/54/KDEL的表达.电穿孔法将重组载体瞬时转染CXCR4高表达的Molt-4,并用流式细胞仪检测CXCR4含量的变化.DNA测序证明:读码框完全正确,重组真核表达载体含有SDF-1α/54基因和编码4肽KDEL的基因,Western blot证明融合蛋白能在COS-7细胞表达.电穿孔转染Molt-4细胞后发现,SDF-1α/54/KDEL可以显著降低胞膜表面CXCR4表达量.由此提示: KDEL介导的SDF-1α/54对Molt-4细胞CXCR4具有表型敲除作用,且此效应不受SDF-1α C端α螺旋缺失的影响.     

趋化因子CXCL12/CXCR4生物轴在肿瘤中的研究进展

趋化因子CXCL12/CXCR4生物轴在肿瘤的演变过程中起着重要的作用,研究表明,高表达CXCR4的肿瘤细胞,可能在CXCL12趋化、牵引下转移至作为配体产生源的某些器官,从而形成器官的特异性转移,因此,目前大量针对拮抗CXCL12/CXCR4生物轴的抗肿瘤治疗效果也陆续得到证实。本文主要是对该生物轴的概念、信号传导通路、作用机制及其在肿瘤中的研究进展进行初步阐述。     

Beta-catenin is a promising key factor in the SDF-1/CXCR4 axis on metastasis of pancreatic cancer

Metastasis is recently the most fearsome of cancer. Pancreatic cancer is the fourth leading cause of cancer death. Morbidity and mortality from pancreatic cancer is conspicuously associated with metastasis. However, the mechanism of metastasis is not well described. Early studies mostly focus on the "soil and seed" hypothesis. Recently, the chemotaxis hypothesis has been paid more attention. Cancer cell with high expression of chemokine receptor will spread to the specific sites where the ligand is highly secreted. It has been demonstrated that SDF-1/CXCR4 signaling, one of the most important chemokine receptor-ligand complexes, was considered to play a critical role in pancreatic cancer organ-specific metastasis through some possible pathways. However, studies do not clarify the mechanism of SDF-1/CXCR4 signaling on pancreatic cancer progression. Beta-catenin, an important factor in canonical Wnt signaling pathway, also makes great contributions on cancer invasion and metastasis. It seems that Wnt/beta-catenin has a significant role in pancreatic cancer progression through interactions with different protein complexes. In the previous study of neural development, the relationship between SDF-1/CXCR4 signaling and beta-catenin has been described. It gave a clue to describe the correlation between SDF-1/CXCR4 signaling and Wnt/beta-catenin pathway. According to this, we postulate that beta-catenin is a promising key factor of SDF-1/CXCR4 signaling to regulate the metastasis of pancreatic cancer. With the stimulation of SDF-1 on highly metastatic pancreatic cancer cells, beta-catenin will separate from different complexes, translocate into the nucleus, trigger the expression of target genes and finally promote the migration of pancreatic cancer cells to specific sites. Through the observation of this crosstalk, it is possible to understand more clearly about the pancreatic cancer specific metastasis and to make some contributions on gene therapy of pancreatic cancer.     

SDF-1α/CXCR4轴通过诱导胰腺癌上皮-间充质转化促进肿瘤迁移和侵袭

目的:探讨SDF-1α/CXCR4轴对胰腺癌细胞迁移和侵袭能力的影响及其作用机制。方法:应用RT-qPCR检测4种胰腺癌细胞株CXCR4 mRNA的表达。Transwell实验检测外源性SDF-1α及其受体CXCR4靶向抑制剂AMD3100对胰腺癌细胞迁移和侵袭能力的影响。MTS法检测外源性SDF-1α及AMD3100对胰腺癌细胞活力的影响。Western blot法检测外源性SDF-1α及AMD3100对胰腺癌细胞上皮-间充质转化(EMT)相关标志物表达的影响。结果:(1) 4种胰腺癌细胞株均不同程度地表达CXCR4 mRNA,其中PANC-1细胞株表达量最高。(2)外源性SDF-1α可增强PANC-1细胞的迁移和侵袭能力,该作用可被AMD3100所阻断。(3)外源性SDF-1α处理PANC-1细胞72 h可增强细胞活力,该作用可被AMD3100阻断。(4)外源性SDF-1α通过上调SNAIL和TWIST促使PANC-1细胞发生EMT,该作用可被AMD3100所阻断。结论:SDF-1/CXCR4轴通过促进胰腺癌细胞发生EMT而促进肿瘤迁移和侵袭。     

Acquisition of lymph node, but not distant metastatic potentials, by the overexpression of CXCR4 in human oral squamous cell carcinoma

Recently, it has been suggested that chemokine/receptor interactions determine the destination of the invasive tumor cells in several types of cancer. It has also been proposed that the stromal cell-derived factor-1 (SDF-1; CXCL12)/CXCR4 system might be involved lymph node metastasis in oral squamous cell carcinoma (SCC). In order to further clarify the role of the SDF-1/CXCR4 system in oral SCC, we generated CXCR4 stable transfectants (IH-CXCR4) using oral SCC cells, and compared them to IH, which did not express CXCR4 and which did not have lymph node metastatic potentials in vivo. We introduced enhanced green fluorescent protein (GFP) fused-CXCR4 into IH cells, and detected the GFP fluorescence in the cytoplasm and cell membrane in approximately 60% of the G418-resistant cells. This bulk-transfectant expressed a high level of CXCR4 mRNA and protein, and exhibited the characteristic calcium fluxes and chemotactic activity observed in treatment with SDF-1. SDF-1 biphasically activated extracellular signal-regulated kinase (ERK)1/2, but continuously activated Akt/protein kinase B (PKB) in IH-CXCR4 cells. Most importantly, IH-CXCR4 cells frequently metastasized to the cervical lymph node, but not to the distant organs in the orthotopic inoculation of nude mice. Furthermore, these lymph node metastases were inhibited by the treatment of a mitogen-activated protein kinase/ERK kinase inhibitor, U0126, or a phosphatidylinositol 3 kinase inhibitor, wortmannin. These results indicate that SDF-1/CXCR4 signaling mediates the establishment of lymph node metastasis in oral SCC via ERK1/2 or Akt/PKB pathway.     

Inhibitors of CXCR4 affect the migration and fate of CXCR4+ progenitors in the developing limb of chick embryos.

Chemokines and their receptors play major roles in numerous physiological and pathological processes during development and disease. CXCR4 is the most abundantly expressed chemokine receptor during development. In contrast to other chemokine receptors, CXCR4 binds and is activated exclusively by its ligand stromal derived factor-1 (SDF-1) or CXCL12. SDF-1 signaling has a wide range of effects on CXCR4-expressing cells depending on the cell type ranging from cell growth to adhesion, chemotaxis, and migration. CXCR4 also serves as a co-receptor for HIV-1 entry into T-cells and has been implicated in the pathogenesis of rheumatoid arthritis and cancer growth and invasion. Numerous inhibitors and antagonists of CXCR4 have been produced and are being tested for their efficiency to target its role in pathogenesis. Our initial expression analysis revealed that CXCR4 is expressed by the migrating myogenic and angiogenic precursors in the developing chick limb. In this study, we used the most specific peptidic inhibitors of CXCR4, T140 and its analog TN14003, to analyse the effect of blocking CXCR4/SDF-1 signaling on the undetermined bioptent migratory progenitors in the developing chick limb. Our results point to defects in migration and an altered differentiation program of these CXCR4-expressing progenitor pool in the limb.     

Possible regulation of migration of intrahepatic cholangiocarcinoma cells by interaction of CXCR4 expressed in carcinoma cells with tumor necrosis factor-alpha and stromal-derived factor-1 released in stroma

Intrahepatic cholangiocarcinoma (ICC) is highly fatal because of early invasion, widespread metastasis, and lack of an effective therapy. We examined roles of CXCR4 and its ligand, stromal cell-derived factor (SDF)-1, in migration of ICC with respect to tumor-stromal interaction by using two ICC cell lines, a fibroblast cell line (WI-38), and 28 human ICC tissues. The two ICC cell lines expressed CXCR4 mRNA and protein, and WI-38 fibroblasts expressed SDF-1 mRNA and protein. Migration of cultured ICC cells in Matrigel was induced by co-culture with WI-38 fibroblasts and by incubation with SDF-1. Anti-SDF-1 antibody suppressed migration, demonstrating that SDF-1 released from WI-38 fibroblasts was responsible for this migration. Tumor necrosis factor (TNF)-alpha pretreatment of ICC cells up-regulated CXCR4 mRNA and protein expression in a concentration-dependent manner. Administration of SDF-1 and TNF-alpha increased synergistically ICC cell migration, which was suppressed by the CXCR4 antagonist AMD3100. In ICC tissue, TNF-alpha was mainly expressed in infiltrated macrophages, CXCR4 in ICC cells, and SDF-1 in stromal fibroblasts. In conclusion, the interaction of SDF-1 released from fibroblasts and CXCR4 expressed on ICC cells may be actively involved in ICC migration, and TNF-alpha may enhance ICC cell migration by increasing CXCR4 expression. CXCR4 could be a therapeutic target to prevent ICC invasion.     

CXCL12 is a key regulator in tumor microenvironment of cervical cancer: an in vitro study

CXCL12 is a small pro-inflammatory chemo-attractant cytokine which signals through chemokine receptor CXCR4. The importance of CXCL12/CXCR4 axis is coming to the fore in several divergent signaling pathway-initiating signals related to cell survival and/or proliferation and cancer metastasis. In the present study we have investigated whether deregulation in CXCR4 signaling (as a consequence of deregulated expression of CXCL12) modulate the metastatic potential of cervical carcinoma cells. We demonstrate that CXCL12 is frequently down regulated and its promoter is hypermethylated in cervical cancer cell lines and primary tumor biopsies. Exogenous treatment of cervical cancer cell lines (HeLa, SiHa and C-33A) with recombinant CXCL12 inhibited the metastasis promoting cell migration, cell invasion and anchorage independent cell growth events. Although this study will need further in vivo validation, our observations suggest that (a) silencing of CXCL12 in cervical cancer cells may be critical in migration and invasion, the key events in cancer cell metastases; (b) cervical cancer cells having down regulated CXCL12 are more prone to being attracted to CXCL12 expressed at secondary sites of metastases; and (c) CXCL12 inhibits anchorage independent cell growth via anoikis. These findings suggest the tumor suppressor functions of CXCL12 in cervical cancer.     

Effects of L-Selectin Stimulation of the Expression of Chemokine Receptor CXCR4 on NK Cells of Healthy Donors and Tumor Patients

We studied the effects of fucoidan (L-selectin ligand) on the expression and SDF-1-induced internalization of CXCR4 receptor on human NK cells of healthy donors and tumor patients. Fucoidan stimulated the expression of surface CXCR4 due to mobilization of the intracellular pool. The effect of fucoidan on CXCR4 expression in cancer patients was low. It was hypothesized that L-selectin-dependent migration of circulating NK cells along the SDF-1 chemokine gradient is reduced in cancer patients.     

Stromal-derived factor-1alpha/CXCL12-CXCR 4 axis is involved in the dissemination of NSCLC cells into pleural space

Malignant pleural effusion (PE) is one of the poor prognostic factors in non-small cell lung cancer (NSCLC), and the detailed mechanism of the malignant PE formation is not fully elucidated. Recently, CXCR4, a receptor for chemokine stromal-derived factor-1alpha (SDF-1alpha) that can induce chemotaxis of cells, was reported to be expressed on NSCLC. In this study, we hypothesized that the SDF-1alpha/CXCR4 axis may be involved in the dissemination of malignant cells into pleural space, and investigated its expression, function, and signaling pathway using NSCLC cell lines and clinical samples from 43 patients with NSCLC with malignant PE. We found functional expression of CXCR4 on NSCLC cell lines, and also found that SDF-1alpha could induce migration via phosphatidylinositol 3 (PI-3) kinase- and p44/42 mitogen-activated protein kinase-dependent manner. The SDF-1alpha levels in malignant PE were significantly higher than those in transudate PE and showed a significant positive correlation with PE volumes. The sensitivity and specificity for prediction of recurrence of malignant PE was 61.5% and 83.3%, respectively (cutoff SDF-1alpha = 2,500 ng/ml), and better than those using pH of PE. Cancer cells in malignant PE expressed CXCR4, and mesothelial cells of the pleura stained positive for SDF-1alpha. The SDF-1alpha/CXCR4 axis is involved in the dissemination of NSCLC cells into pleural space.     

Salmonella reduces tumor metastasis by downregulation C-X-C chemokine receptor type 4

Tumor metastasis is the main reason for the death of most cancer patients. C-X-C chemokine receptor type 4 (CXCR4) has been demonstrated to be overexpressed in numerous types of cancer. CXCR4 selectively binds with stromal cell-derived factor 1 (SDF1), also known as C-X-C family chemokine ligand 12 (CXCL12) (CXCL12/SDF-1), which induced tumor proliferation and metastasis. Recently, the use of conventional cancer treatments had some limitation; bacteria treatment for cancer becomes a trend that overcomes these limitations. Plenty of studies show that Salmonella has anti-tumor and anti-metastatic activity. The current study aimed to investigate Salmonella suppresses CXCR4 protein expression and tumor cell migration ability in B16F10 melanoma and LL2 lung carcinoma cells. Salmonella reduced CXCR4 protein expression through downregulating Protein Kinase-B (Akt)/Mammalian Target of Rapamycin (mTOR) signaling pathway. In cells transfected with constitutively active Akt plasmids, a reverse effect of Salmonella-induced inhibition of CXCR4 was observed. Tumor cells have chemotactic response to CXCL12 in migration assay, and we found that Salmonella reduced tumor chemotactic response after CXCL12 treatment. The C57BL/6 mice were intravenously injected with B16F10 and LL2 cells pre-incubated with or without Salmonella, the tumor size and lung weight of Salmonella group had obviously decreased, indicating anti-metastatic effect that confirmed the findings from the in vitro experiments.