CXCR7对HeLa细胞增殖、粘附和侵袭能力的影响

基质细胞衍生因子-1(SDF-1)在肿瘤侵袭、转移过程中起着重要的调控作用.此前认为SDF-1是通过其唯一受体CXCR4来起作用.近年来发现SDF-1还有另一作用受体——CXCR7,SDF-1/CXCR7在部分肿瘤侵袭转移过程中起重要作用,但其在宫颈癌HeLa细胞中的作用目前尚未明确.通过Western blotting检测HeLa细胞中CXCR4和CXCR7的表达,阻断CXCR4或CXCR7后,通过MTT法评价细胞增殖能力,细胞粘附实验评价细胞粘附能力,Transwell实验评价细胞侵袭能力.结果表明,CXCR4和CXCR7在HeLa细胞中表达.阻断CXCR4或CXCR7后,SDF-1诱导的HeLa细胞增殖、侵袭和与内皮细胞的粘附能力均被阻断.结果提示CXCR7在SDF-1诱导HeLa细胞增殖、侵袭和与内皮细胞的粘附过程中起着重要作用,将有望成为治疗宫颈癌转移的新靶点.     

eIF4E在CXCL12诱导的胃癌转移中的作用和机制

探讨e IF4E在CXCL12诱导胃癌细胞形态学改变和迁移中的作用和机制.在胃癌细胞株(SGC7901,MGC803)上给予CXCL12处理,显微镜下观察细胞形态的改变;通过transwell实验检测CXCL12对胃癌细胞迁移能力的影响;在SGC7901上给予CXCL12处理,用Western blot检测e IF4E磷酸化和总蛋白水平的变化;用脂质体转染e IF4E的小干扰RNA,检测e IF4E对胃癌细胞形态学和迁移的影响;以及用qRT-PCR检测与肿瘤侵袭转移密切相关的因子MMP9的mRNA水平的表达.结果显示,给予CXCL12处理,胃癌细胞形态由上皮表型向长梭形的间叶样表型转变,细胞的迁移能力提高.在相同浓度的CXCL12处理情况下,转染e IF4E siRNA抑制e IF4E的表达,可抑制CXCL12诱导的细胞的形态学改变和迁移能力.另外,CXCL12引起与肿瘤转移密切相关因子MMP9的mRNA水平的表达升高,而用siRNA抑制e IF4E的表达,可下调MMP9的mRNA表达水平.结论:CXCL12激活了e IF4E,阻抑e IF4E的表达抑制CXCL12诱导的形态学改变和细胞迁移,其作用机制可能与上调MMP9的表达有关.     

SDF-1α改善高糖对骨髓间充质干细胞存活及迁移能力的抑制作用与分子机制的研究

目的:探讨基质细胞衍生因子-1α(SDF-1α)对高糖环境(25 mmol/L)下大鼠骨髓间充质干细胞(r MSCs)存活及迁移能力的影响及相关分子机制.方法:采用全髓贴壁法纯化培养r MSCs,通过MTT法检测细胞增殖率、Hoechst 33258染色从形态学角度观察细胞凋亡评估SDF-1α对高糖环境下r MSCs存活的影响,同时通过transwell实验评估SDF-1α对高糖环境下r MSCs细胞迁移能力的影响.结果:实验结果发现,与低糖培养液(5.6mmol/L)比较,高糖培养液可明显抑制r MSCs增殖、促进细胞凋亡(P0.05),SDF-1α(50 ng/m L)可减轻高糖培养液对细胞增殖的抑制及诱导细胞凋亡的作用(P0.05),CXCR4受体特异性拮抗剂AMD3100(10μg/m L)虽能进一步抑制细胞增殖、诱导细胞凋亡,但差异无显著性(P0.05).Transwell实验发现高糖培养液可明显抑制r MSCs的迁移作用(P0.05),SDF-1α(50 ng/m L)可逆转高糖培养液对细胞迁移的抑制作用(P0.05),AMD3100(10μg/m L)可进一步抑制细胞迁移,且差异有显著性(P0.05).结论:SDF-1α可能通过CXCR4受体改善高糖对骨髓间充质干细胞迁移能力的抑制,而其改善高糖对骨髓间充质干细胞存活的抑制则可能通过非CXCR4受体介导,为改善MSCs用于治疗冠心病合并糖代谢异常患者心梗后心力衰竭疗效进一步提供理论依据.     

趋化因子 CXCL16及其受体 CXCR6在恶性肿瘤中的表达与作用

趋化因子在恶性肿瘤的发生、发展、肿瘤微环境形成及抗肿瘤免疫中发挥了重要作用。新的趋化因子CXCL16及其受体 CXCR6正日益受到关注。研究发现 CXCL16/CXCR6在多种人类恶性肿瘤中高表达,在多数肿瘤中可促进肿瘤的生长、转移和复发,但在有些肿瘤中却作用相反。此外,CXCL16/CXCR6还可通过诱导CD4+/CD8+T 细胞、自然杀伤细胞等免疫细胞参与抗肿瘤免疫以及肿瘤微环境的形成。明确 CXCL16/CXCR6在肿瘤中的作用及其分子机制将有助于抗肿瘤研究的深入。     

整合素在肝癌细胞侵袭和转移中的作用

癌细胞与细胞外基质（ECM）的粘附是恶性肿瘤侵袭首要步骤。肿瘤细胞与细胞外基质的粘附是通过细胞膜表达的特异受体介导的，其中整合素家族为重要的粘附分子。对整合素表达相关的细胞外基质的介绍及肝癌细胞侵袭与转移中整合素研究的综述，可了解相关的整合素所介导肝癌细胞与细胞外基质、肝癌细胞之间的相互作用。文中提及肝癌细胞趋化运动中相关的整合素，有助于进一步了解整合素在肝癌侵袭与转移中的作用。整合素参与了整个肝癌细胞的侵袭转移过程，寻找出干扰整合素与配体相互作用、特异性增加或减少整合素在肿瘤中的表达的物质，从而阻断肿瘤的侵袭与转移，对抗癌药物的研究有着深远的影响。     

趋化因子IL-8和受体CXCR1,CXCR2在胃肠和肝肿瘤中的表达

为研究趋化因子IL-8和受体CXCR1、CXCR2在胃肠和肝肿瘤中的作用,应用免疫组织化学和RT-PCR的方法检测了趋化因子IL-8和受体CXCR1、CXCR2在食道癌、胃癌、结直肠癌和肝癌中的表达。在胃肠肿瘤中,CXCR1在癌细胞的细胞核膜和细胞质中表达,CXCR2在癌细胞的细胞质中表达。在肝癌中,CXCR1和CXCR2在癌巢中有表达而在邻近的肝组织中无表达。应用RT-PCR的方法检测了受体CXCR1、CXCR2的转录,其结果证实了免疫组织化学的结果。在胃肠和肝肿瘤中检测到了IL-8的表达。进一步分析表明在胃肠和肝肿瘤中IL-8与CXCR1/CXCR2共表达(p=0.0448)。实验结果说明趋化因子IL-8和受体CXCR1、CXCR2可能在胃肠和肝肿瘤的发生和发展中起作用。     

CXCL13参与AR促进前列腺癌细胞体内异种移植瘤的生长

CXCL13作为受AR调节的靶基因之一,参与AR在几株前列腺癌细胞系中的调节功能已有报道.本研究进一步探讨在裸鼠皮下异种移植瘤模型中CXCL13参与AR对前列腺癌增殖作用的调节,从而验证体外实验的结果.选用CRPC细胞系CWR22Rv1筛选稳定表达AR-N或CXCL13的细胞株,分为CWR22Rv1(对照)、CWR22Rv1/AR-N、CWR22Rv1/AR-N+si CXCL13、CWR22Rv1/CXCL13 4个组别,裸鼠皮下成瘤30 d后,解剖取瘤.其中CWR22Rv1/AR-N+si CXCL13组为用CWR22Rv1/AR-N细胞成瘤至100 mm~3后,再瘤内注射si CXCL13,每3 d一次,共注射3次.通过形态学观察、测定裸鼠体重和肿瘤大小,发现过表达AR和CXCL13组肿瘤明显大于对照组,而过表达AR再抑制CXCL13组肿瘤明显小于过表达AR组,也比过表达CXCL13组略小,但各组小鼠的体重没有明显变化; Western blot和免疫组织化学结果显示过表达AR-N或CXCL13均能提高ETS-1、Cyclin B1和Snail的表达,而敲减CXCL13后显著削弱AR的调节作用.表明CXCL13参与AR调节前列腺癌细胞小鼠体内异种移植瘤的生长.     

胰腺癌细胞与神经相互作用对MIA PaCa-2转移侵袭的影响及机制研究

为了探讨胰腺癌细胞MIAPaCa-2与神经的相互作用对MIAPaCa-2增殖、凋亡、转移和侵袭能力的影响,及其在上皮间质转化和嗜神经侵袭进程中的作用,建立了MIA PaCa-2和小鼠神经共培养模型,收集上清,用其处理MIAPa-Ca-2 细胞,通过流式细胞术观察 CD133⁺/CXCR4⁺双染比例变化;Transwell 实验检测 MIA PaCa-2/神经相互作用和CD133对胰腺癌细胞转移侵袭能力的影响; Western blotting 检测不同处理组相关蛋白的表达;CCK-8检测其对MIA Pa-Ca-2增殖能力的影响.结果显示共培养上清处理过的MIA PaCa-2细胞中CD133⁺/CXCR4⁺双阳性比例显著高于普通培养基组(P<0.05),MIA PaCa-2/神经相互作用和 CD133 促进MIA PaCa-2增殖、转移和侵袭,提高其抗凋亡能力,上调Vimentin和Slug的表达.表明MIA PaCa-2/神经相互作用可提高胰腺癌细胞中CD133⁺/CXCR4⁺双阳比例,促进细胞增殖,抑制凋亡,调控细胞上皮间质转化进程,并诱导其转移侵袭.     

牡蛎低分子活性肽BPO-L对人肺腺癌A549细胞周期和相关癌基因、抑癌基因表达的调控作用

采用酸抽提、凝胶柱层析等方法,从僧帽牡蛎体内分离提取到牡蛎低分子活性多肽组分BPO-L,以HMBA处理组为平行对照,流式细胞仪检测细胞周期变化及以免疫细胞化学方法检测相关癌基因、抑癌基因表达变化.研究BPO-L对人肺腺癌A549细胞分化的生物学效应,探索其对肺癌细胞的作用机理.实验结果显示,BPO-L能有效抑制A549细胞增殖活动,促使细胞阻滞于G0/G1期.在此过程中,A549细胞c-myc,MTp53等癌基因蛋白表达减弱,p21WAF1/CIP1和Rb等抑癌基因蛋白表达活性的增强.本研究证实BPO-L对肺癌细胞具有显著的诱导分化作用.其诱导癌细胞分化机理与其调节和干预c-myc、MTp53等癌基因与p21WAF1/CIP1和Rb等抑癌基因的表达有关.     

CXCL1在子宫内膜样腺癌中的表达及其对Ishikawa细胞增殖侵袭的影响

目的:研究趋化因子配体1 (CXCL1)在子宫内膜样腺癌中的表达及其对人子宫内膜高分化腺癌细胞株Ishikawa细胞增殖、凋亡、迁移能力及侵袭能力的影响,以及CXCL1因子与子宫内膜样腺癌的发生及浸润转移的关系.方法:免疫组化法检测CXCL1在子宫内膜样腺癌患者的子宫内膜组织子宫内膜非典型增生患者的子宫内膜组织及正常增生期子宫内膜组织中的表达,QRT-PCR法检测子宫内膜样腺癌组织与癌旁组织中CXCL1 mRNA的相对表达;体外运用siRNA沉默Ishikawa细胞中CXCL1的基因表达,分别通过CCK8法及流式细胞仪法检测沉默CXCL1对细胞增殖及凋亡的影响,划痕实验及transwell法检测对细胞迁移能力与侵袭能力的影响,Western Blot检测pNF-κB,MMP9及Caspase-3的蛋白表达.结果:免疫组化及QRT-PCR结果显示,子宫内膜样腺癌组织中CXCL1表达升高,有淋巴结转移、分期较晚及肿瘤直径较大的患者的子宫内膜组织中表达显著升高;在CXCL1沉默组中,细胞增殖、迁移能力及侵袭能力下降,凋亡率增加,凋亡蛋白Caspase-3表达升高,pNF-κB,MMP9蛋白表达降低(P0.05).结论:CXCL1在子宫内膜样腺癌组织中高表达,沉默CXCL1可能通过下调磷酸化NF-κB抑制Ishikawa细胞的增殖、迁移能力及侵袭能力,促进细胞凋亡.     

Involvement of chemokine receptors in breast cancer metastasis

Breast cancer is characterized by a distinct metastatic pattern involving the regional lymph nodes, bone marrow, lung and liver. Tumour cell migration and metastasis share many similarities with leukocyte trafficking, which is critically regulated by chemokines and their receptors. Here we report that the chemokine receptors CXCR4 and CCR7 are highly expressed in human breast cancer cells, malignant breast tumours and metastases. Their respective ligands CXCL12/SDF-1alpha and CCL21/6Ckine exhibit peak levels of expression in organs representing the first destinations of breast cancer metastasis. In breast cancer cells, signalling through CXCR4 or CCR7 mediates actin polymerization and pseudopodia formation, and subsequently induces chemotactic and invasive responses. In vivo, neutralizing the interactions of CXCL12/CXCR4 significantly impairs metastasis of breast cancer cells to regional lymph nodes and lung. Malignant melanoma, which has a similar metastatic pattern as breast cancer but also a high incidence of skin metastases, shows high expression levels of CCR10 in addition to CXCR4 and CCR7. Our findings indicate that chemokines and their receptors have a critical role in determining the metastatic destination of tumour cells.     

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

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 of the CXCR4-specific ligand stromal cell-derived factor-1alpha (ref. 1). It is still uncertain how an evolving tumour cell is reprogrammed to express CXCR4, thus implementing the tendency to metastasize to specific organs. Here we show that the von Hippel-Lindau tumour suppressor protein pVHL negatively 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 gene in most cases revealed an association of strong CXCR4 expression with poor tumour-specific survival. These results suggest a mechanism for CXCR4 activation during tumour cell evolution and imply that VHL inactivation acquired by incipient tumour cells early in tumorigenesis confers not only a selective survival advantage but also the tendency to home to selected organs.     

Suppression of murine breast cancer metastasis by selective inhibition of CXCR4 by synthetic polypeptide derived from viral macrophage inflammatory protein II

Stromal cell-derived factor-1 and its receptor CXC chemokine receptor-4 (CXCR4) have been implicated in breast cancer metastasis. A significant association between HER2 and CXCR4 expression has been observed in human breast tumor tissues, and overexpression of CXCR4 is essential for HER2-mediated tumor metastasis. Moreover, CXCR4 expression is low in normal breast tissues and high in malignant tumors, suggesting that a blockade of CXCR4 may limit tumor metastasis. The present study investigated the action of a synthetic antagonist 21-mer peptide derived from viral macrophage inflammatory protein II against CXCR4 (NT21MP) in inhibiting metastasis in vitro and in vivo. The results showed that chemotaxis of SKBR3 cells toward SDF-1α was reduced by NT21MP in a dose-dependent manner (P < 0.05). NT21MP inhibited tumor growth at 500 μg/kg and in combination with Herceptin, the anti-HER2 antibody. The in vivo metastatic assay showed that NT21MP significantly inhibited pulmonary metastasis, and the number of metastatic tumor nodes on the surface of the lung was greatly decreased. Compared with the saline-treated control group, PCNA expression was dose-dependently decreased by NT21MP, the percentage of apoptotic cells was increased, and CXCR4 mRNA and protein expression were downregulated. In conclusion, NT21MP inhibits cellular prolifer-ation, promotes apoptosis by downregulating CXCR4 expression, and suppresses the progression of primary and metastatic tumors. CXCR4 may be a useful therapeutic target for breast cancer, and NT21MP may serve as a potential target drug for the treatment of breast cancer metastasis.     

Evidence for existence of a close association between CD14 and CXCR4 on monocytic cell line U937

The surface expression of HIV-1 coreceptors (CXCR4 and CCR5) on monocytes can be regulated by the ligand of CD14,and the susceptibility of the cells to HIV-1 is then changed.Our previous study found that monoclonal antibody against CD14 could dramatically inhibit CXCR4-mediated chemotaxis and cell-cell fusion.Based on these studies,we explored potential relationship between CD14 and CXCR4 on monocytic cell line U937.Flow cytometry analysis showed that anti-CXCR4 monoclonal antibody (mAb) 12G5 strongly inhibited binding of the FITC-conjugated anti-CD14 monoclonal antibodies (TUK4 and UCHM1) to U937,while another CX- CR4-specific mAb B-R24 did not show any effect on this binding.On the other hand,two anti-CD14 monoclonal antibodies (TUK4 and UCH-M1) obviously inhibited the binding of the PE-conjugated anti-CXCR4 mAb 12G5 to U937 but did not inhibit the binding of mAb 12G5 to CXCR4-transfected 3T3 cells (3T3.T4.CXCR4),which indicates that the blocking of mAb 12G5 binding to CXCR4 by CD14- specific mAbs is not involved in the possibility that CD14-specific mAbs directly bind to CXCR4.These results suggested existence of a close association between CD14 and CXCR4 on monocytic cell line U937.     

Evidence for existence of a close association between CD14 and CXCR4 on monocytic cell line U937

The surface expression of HIV-1 coreceptors (CXCR4 and CCR5) on monocytes can be regulated by the ligand of CD14, and the susceptibility of the cells to HIV-1 is then changed. Our previous study found that monoclonal antibody against CD14 could dramatically inhibit CXCR4-mediated chemotaxis and cell-cell fusion. Based on these studies, we explored potential relationship between CD14 and CXCR4 on monocytic cell line U937. Flow cytometry analysis showed that anti-CXCR4 monoclonal antibody (mAb) 12G5 strongly inhibited binding of the FITC-conjugated anti-CD14 monoclonal antibodies (TUK4 and UCHM1) to U937, while another CXCR4-specific mAb B-R24 did not show any effect on this binding. On the other hand, two anti-CD14 monoclonal antibodies (TUK4 and UCH-M1) obviously inhibited the binding of the PE-conjugated anti-CXCR4 mAb 12G5 to U937 but did not inhibit the binding of mAb 12G5 to CXCR4-transfected 3T3 cells (3T3.T4.CXCR4), which indicates that the blocking of mAb 12G5 binding to CXCR4 by CD14-specific mAbs is not involved in the possibility that CD14-specific mAbs directly bind to CXCR4. These results suggested existence of a close association between CD14 and CXCR4 on monocytic cell line U937.     

空间辨别性学习记忆活动对大鼠海马齿状回SDF-1免疫阳性细胞的影响

目的:探讨空间辨别性学习记忆活动引致大鼠海马形态学可塑与海马齿状回内基质细胞衍生因子-1(SDF-1)表达的关系。方法:用水迷宫训练SD大鼠建立空间辨别性学习记忆模型,用免疫组化方法和图像分析技术检测大鼠海马齿状回SDF-1免疫阳性细胞的变化。结果:(1)对照组大鼠海马齿状回可见少量SDF-1免疫阳性细胞,阳性细胞胞体呈圆形或椭圆形,胞核较大,胞浆呈棕黄色。阳性细胞主要分布在齿状回颗粒细胞层;游水组大鼠海马齿状回SDF-1免疫阳性细胞的数量和形态与对照组的相比未见差异;模型组大鼠海马齿状回SDF-1免疫阳性细胞数量随着训练时间逐渐增多,细胞形态同对照组,胞浆呈深棕黄色,并有一至多个突起。(2)对照组与游水组7、14、21 d的大鼠海马齿状回SDF-1免疫阳性细胞在形态和数量未见统计学差异(P>0.05);对照组与模型组7、14 d大鼠海马齿状回SDF-1免疫阳性细胞的形态和数量未见统计学差异(P>0.05);模型21 d大鼠齿状回SDF-1免疫阳性细胞的形态和数量与对照组的比有明显统计学差异(P<0.01)。结论:大鼠海马齿状回内SDF-1阳性细胞可能参与空间辨别性学习记忆活动引致的形态学可塑性。     

In vivo imaging of specialized bone marrow endothelial microdomains for tumour engraftment

The organization of cellular niches is known to have a key role in regulating normal stem cell differentiation and regeneration, but relatively little is known about the architecture of microenvironments that support malignant metastasis. Using dynamic in vivo confocal imaging, here we show that murine bone marrow contains unique anatomic regions defined by specialized endothelium. This vasculature expresses the adhesion molecule E-selectin and the chemoattractant stromal-cell-derived factor 1 (SDF-1) in discrete, discontinuous areas that influence the homing of a variety of tumour cell lines. Disruption of the interactions between SDF-1 and its receptor CXCR4 inhibits the homing of Nalm-6 cells (an acute lymphoblastic leukaemia cell line) to these vessels. Further studies revealed that circulating leukaemic cells can engraft around these vessels, suggesting that this molecularly distinct vasculature demarcates a microenvironment for early metastatic tumour spread in bone marrow. Finally, purified haematopoietic stem/progenitor cells and lymphocytes also localize to the same microdomains, indicating that this vasculature might also function in benign states to demarcate specific portals for the entry of cells into the marrow space. Specialized vascular structures therefore appear to delineate a microenvironment with unique physiology that can be exploited by circulating malignant cells.     

SDF1—3‘A多态在中国人群中的分布

ＣＸＣＲ４是嗜Ｔ型ＨＩＶ－１的一个共受体,基质细胞衍生因子是ＣＸＲ４的配体。国外最新报道ＳＤＦ１基因３’非编码区８０１位Ｇ→Ａ的多态与推迟爱滋病的发生相关。