CXCR7与肿瘤

CXCR7作为新近发现的趋化因子CXCL12的另一个受体,被证实与肿瘤的发生发展密切相关,逐渐成为了研究的热点。我们综合近年来有关该基因与肿瘤关系的研究做一综述。     

CXCL12/CXCR4轴在肿瘤生长和转移中的作用及其机制

近年来,趋化因子在肿瘤生长和转移中的作用引起人们的强烈关注。在多种肿瘤中（包括乳腺癌、胰腺癌、前列腺癌、结直肠癌等）发现,CXCL12/CXCR4分子对能够促进肿瘤细胞的生长,抑制肿瘤细胞的凋亡,促进肿瘤血管生成,影响某些肿瘤的靶向转移,增强肿瘤细胞的黏附和迁移能力,影响肿瘤细胞的分泌行为,提示该轴可能成为抗肿瘤药物的新靶点,具有潜在的临床应用前景。     

趋化因子CXCL12/CXCR4与肿瘤关系的研究进展

CXCL12及其受体CXCR4不仅在许多生命过程中发挥着重要的调控作用而且与肿瘤细胞的生长、增殖、侵袭、转移有密切的关系。本文将围绕CXCR4、CXCL12以及CXCL12/CXCR4轴在肿瘤增殖、侵袭、转移、肿瘤血管生成中的作用以及作用原理以及临床应用作一综述。     

SDF-1/CXCR4及CCL19/21-CCR7与肿瘤的关系

趋化因子(Chemokine)是一类可诱导的,由多种细胞产生,有激活和趋化白细胞作用,分子量为7KDa～10KDa的促炎细胞因子,它们在抗感染和免疫中有至关重要的作用.根据其前两个半胱氨酸残基的相对位置不同,将它们分为了四大类:CXC趋化因子,CC趋化因子,C趋化因子和CX3C趋化因子.相应的趋化因子受体则分为CXC趋化因子受体(CXCR),CC趋化因子受体(CCR),C趋化因子受体(CR)和CX3C趋化因子受体(CX3CR),但它们都为GPCR家族成员(一类介导趋化因子使功能性GTP-蛋白耦连的七次跨膜受体).     

CXCL12-CXCR4在消化道肿瘤转移中的研究进展

趋化因子CXCL12及其受体CXCR4不仅表达于免疫细胞,在某些肿瘤细胞中也呈高表达.最近研究表明,其与食管癌、胃癌、结直肠癌等的转移密切相关.展开其生物学特性、在消化道肿瘤中的表达及转移相关性研究,将为消化道肿瘤转移的防治提供新的思路.     

趋化因子受体CXCR4在乳腺癌中的表达及临床意义

目的:探讨乳腺癌中趋化因子受体CXCR4的表达及临床意义.方法: 采用免疫组化S-P染色法检测乳腺癌、乳腺增生组织、及乳腺纤维腺瘤中CXCR4表达,分析CXCR4在乳腺癌中表达与患者淋巴结转移状态、Her2、PCNA关系.结果: CXCR4在乳腺癌组织中高表达,与乳腺增生组织及乳腺纤维腺瘤组织中表达有显著性差异,与患者淋巴结转移状态、Her2、PCNA密切相关.结论: CXCR4在乳腺癌中高表达,可以作为乳腺癌患者预后的一个指标,为寻找新的乳腺癌治疗靶点提供了依据.     

趋化因子受体CXCR4在乳腺癌中的表达及临床意义

目的：探讨乳腺癌中趋化因子受体CXCR4的表达及临床意义。方法：采用免疫组化S—P染色法检：测乳腺癌、乳腺增生组织、及乳腺纤维腺瘤中CXCR4表达,分析CXCR4在乳腺癌中表达与患者淋巴结转移状态、Her2、PCNA关系。结果：CXCR4在乳腺癌组织中高表达,与乳腺增生组织及乳腺纤维腺瘤组织中表达有显著性差异,与患者淋巴结转移状态、Her2、PCNA密切相关。结论：CXCR4在乳腺癌中高表达,可以作为乳腺癌患者预后的一个指标,为寻找新的乳腺癌治疗靶点提供了依据。     

SDF-1/CXCR7在肝细胞癌中的表达及临床意义

目的：研究趋化因子SDF-1及其受体CXCR7在肝细胞癌组织中的表达,探讨其表达水平与临床病理特征的关系。方法：采用SP免疫组织化学法检测55例肝细胞癌标本及28例正常肝组织标本中SDF-1、CXCR7的表达。结果：SDF-1、CXCR7在正常肝组织表达均阴性,癌组织中二者阳性表达率分别为63.6%和78.2%;SDF-1表达于癌细胞及间质上皮细胞,CXCR7主要表达于间质内皮细胞,SDF-1表达与门静脉癌栓有关,CXCR7表达与肝内病灶数目、门静脉癌栓有关。结论：SDF-1/CXCR7生物学轴通过促进新生血管生成,参与肝细胞癌的侵袭和转移。有望成为判断肝细胞癌侵袭性及预后的指标。     

结直肠癌CXCL12-CXCR4/CXCR7轴作用机制研究进展

目的 探讨趋化因子CXCL12及其受体与结直肠癌的关系,以总结最新研究进展。方法 应用PubMed、Web of Science数据库和中国期刊全文数据库(CNKI)检索系统,以“结直肠癌、CXCL12、CXCR4、CXCR7、靶向治疗和趋化因子等”为中文关键词,以“colorectal cancer、CXCL12、CXCR4、CXCR7、targeted therapy、chemokines”等为英文关键词,检索2010-01-01-2022-03-31的相关文献,共检索到中文文献76篇,英文文献256篇。纳入标准：(1)结直肠癌发生时CXCL12、CXCR4和CXCR7表达水平变化;(2)CXCL12-CXCR4/CXCR7轴对结直肠癌发生发展的影响及作用机制;(3)靶向干预CXCL12-CXCR4/CXCR7轴对结直肠癌的影响及相关临床研究。排除标准：结直肠癌与非CXCL12/CXCR4或CXCL12/CXCR7信号轴。最终共纳入分析文献56篇,中文16篇,英文40篇。结果 CXCL12及其受体在结直肠癌组织及常见转移部位表达显著升高,相关分子信号可通过CXCL12-CXCR4/...     

SDF-1/CXCR7轴与肿瘤的研究进展

基质细胞衍生因子-1（SDF-1）及其受体CXCR4所构成的SDF-1/CXCR4生物轴在肿瘤发生、发展及肿瘤血管新生中发挥重要作用。最近研究发现CXCR7也是SDF-1的受体,且与肿瘤密切相关。全文就SDF-1新受体CXCR7的生物学特征,SDF-1/CXCR7轴在肿瘤细胞中的表达,SDF-1/CXCR7轴与肿瘤细胞增殖和存活、肿瘤侵袭和转移以及肿瘤血管新生的关系作一综述。     

The Role of chemokine receptor CXCR4 in breast cancer metastasis

Breast cancer is one of the leading causes of cancer related deaths worldwide. Breast cancer-related mortality is associated with the development of metastatic potential of primary tumor lesions. The chemokine receptor CXCR4 has been found to be a prognostic marker in various types of cancer, including breast cancer. Recent advances in the field of cancer biology has pointed to the critical role that CXCR4 receptor and its ligand CXCL12 play in the metastasis of various types of cancer, including breast cancer. Breast tumors preferentially metastasize to the lung, bones and lymph nodes, all of which represent organs that secrete high levels of CXCL12. CXCL12 acts as a chemoattractant that drives CXCR4-positive primary tumor cells towards secondary metastatic sites leading to the onset of metastatic lesions. Since its discovery in 2001, the CXCR4 field has progressed at a very fast rate and further studies have pointed to the role of CXCR4 in dissemination of tumor cells from primary sites, transendothelial migration of tumor cells as well as the trafficking and homing of cancer stem cells. This review summarizes the information that has been obtained over the years regarding the role of CXCL12-CXCR4 signaling in breast cancer, discusses its potential application to the development of new therapeutic tools for breast cancer control, and elucidates the potential therapeutic challenges which lie ahead and the future directions that this field can take for the improvement of prognosis in breast cancer patients.     

CXCL12，CXCR4及CXCR7表达检测对乳腺癌患者疾病预后意义探讨

目的：探讨乳腺癌患者肿瘤组织中CXCL12,CXCR4和CXCR7 mRNA表达情况在肿瘤转移和疾病预后中的价值。方法采用定量PCR方法检测115例乳腺癌,临近正常组织及乳腺癌肿瘤转移患者颈部淋巴结样本中CXCL12,CXCR4和CXCR7 mRNA表达情况。随访资料采用Kaplan-Meier生存分析,对影响生存质量的因素进行多重变量Cox回归分析。结果与正常组织相比,乳腺癌组织中CXCR4和CXCR7表达明显增加,差异均有统计学意义（P﹤0.001）,两种组织中CXCL12的表达差异无统计学意义（P﹥0.05）;CXCL12在肿瘤原发部位和淋巴结转移部位的表达差异有统计学意义（P﹤0.05）,转移瘤的CXCR4和CXCR7表达均增加（P﹤0.05）。Kaplan-Meier生存分析结果表明,与CXCR4和CXCR7低表达患者相比,高表达患者的总生存率较低（P﹤0.05）。Cox回归模型显示,CXCL12、CXCR4和CXCR7表达均为影响乳腺癌患者生存情况的独立因素。结论本研究结果表明CXCL12、CXCR4和CXCR7 mRNA表达在乳腺癌患者肿瘤发展和转移中发挥重要作用,可以作为乳腺癌患者疾病预后的生物标志物。     

Correlation between CXCR4/CXCR7/CXCL12 chemokine axis expression and prognosis in lymph‐node‐positive lung cancer patients

The CXCR4/CXCR7/CXCL12 chemokine axis plays important roles in the migration of tumor cells during cancer development by modulating site‐specific distant metastasis including to regional lymph nodes. We investigated the correlation of these chemokine expressions to prognosis in lymph‐node‐positive non‐small‐cell lung cancer (NSCLC) patients. A total of 140 surgically resected specimens of primary site (PS) and metastatic lymph nodes (MLN) of NSCLC involving hilar and/or mediastinal lymph nodes (N1‐2) were collected. CXCR4, CXCR7 and CXCL12 expressions were evaluated. Cox regression analysis was performed to determine whether these chemokines were independent prognostic factors in N1‐2 NSCLC. High expression of CXCR4 in PS and CXCL12 in MLN was associated with poor overall survival (OS) (P = .025 and .033, respectively). Significant correlations between CXCR4 expression in PS and CXCL12 expression in MLN were observed (P = .040). There was significant difference in OS between 2 groups according to expressions of CXCR4 in PS and CXCL12 in MLN (P = .0033). Expression of CXCL12 in MLN was identified as an independent prognostic factor (HR 1.79, 95% CI 1.08‐3.04, P = .023). CXCL12 in MLN was mainly expressed by tumor cells compared with stromal cells (56% vs 25%, respectively, P < .0001). CXCR4/CXCL12 may play roles in tumor progression in MLN and is associated with poor prognosis of lymph‐node‐positive NSCLC patients.     

CXCR7 expression is associated with disease-free and disease-specific survival in cervical cancer patients

Background:

The CXC chemokine receptor (CXCR)7 is involved in tumour development and metastases formation. The aim of the present study was to determine protein expression of CXCR7, its putative co-receptors epidermal growth factor receptor (EGFR) and CXCR4, its predominant ligand CXCL12, their co-dependency and their association with survival in cervical cancer patients.

Methods:

CXC chemokine receptor 7, EGFR, CXCR4 and CXCL12 expression were determined immunohistochemically in 103 paraffin-embedded, cervical cancers. Subsequently, associations with patient characteristics were assessed and survival analyses were performed.

Results:

CXC chemokine receptor 7 was expressed by 43% of tumour specimens, in a large majority of cases together with either EGFR or CXCR4 (double positive), or both (triple positive). The CXCR7 expression was associated with tumour size (P=0.013), lymph node metastasis (P=0.001) and EGFR expression (P=0.009). CXC chemokine receptor 7 was independently associated with disease-free survival (hazard ratio (HR)=4.3, 95% confidence intervals (CI) 1.7–11.0, P=0.002), and strongly associated with disease-specific survival (HR=3.9, 95% CI 1.5–10.2, P=0.005).

Conclusion:

CXC chemokine receptor 7 expression predicts poor disease-free and disease-specific survival in cervical cancer patients, and might be a promising new therapeutic marker. In a large majority of cases, CXCR7 is co-expressed with CXCR4 and/or EGFR, supporting the hypothesis that these receptors assist in CXCR7 signal transduction.     

CXCR7在疾病发生和发展中的作用

趋化性细胞因子(chemokine)是一个蛋白质家族,由60余种结构同源、8-10kDa大小的多肽组成,负责吸引白细胞、胚胎细胞、肿瘤细胞,参与炎症反应、组织发育和肿瘤形成.近期发现一种新型受体即CXCR7,广泛分布于软骨、心脏、脑、脾、肾和多种肿瘤细胞,与CXCL12和CXCL11相互作用,促进细胞迁移、血管新生、肿瘤发生、侵袭、转移和抗细胞凋亡.本文将对其发现、结构、分布、组织表达、功能以及与癌症相关作用等方面进行综述.     

CXCR4/CXCL12 expression and signalling in kidney cancer

CXCL12 (SDF-1), a CXC-chemokine, and its specific receptor, CXCR4, have recently been shown to be involved in tumourgenesis, proliferation and angiogenesis. Therefore, we analysed CXCL12alpha/CXCR4 expression and function in four human kidney cancer cell lines (A-498, CAKI-1, CAKI-2, HA-7), 10 freshly harvested human tumour samples and corresponding normal kidney tissue. While none of the analysed tumour cell lines expressed CXCL12alpha, A-498 cells were found to express CXCR4. More importantly, real-time RT-PCR analysis of 10 tumour samples and respective adjacent normal kidney tissue disclosed a distinct and divergent downregulation of CXCL12alpha and upregulation of CXCR4 in primary tumour tissue. To prove that the CXCR4 protein is functionally active, rhCXCL12alpha was investigated for its ability to induce changes of intracellular calcium levels in A-498 cells. Moreover, we used cDNA expression arrays to evaluate the biological influence of CXCL12alpha. Comparing gene expression profiles in rhCXCL12alpha stimulated vs unstimulated A-498 kidney cancer cells revealed specific regulation of 31 out of 1176 genes tested on a selected human cancer array, with a prominent stimulation of genes involved in cell-cycle regulation and apoptosis. The genetic changes reported here should provide new insights into the developmental paths leading to tumour progression and may also aid the design of new approaches to therapeutic intervention.     

Inhibition of CXCR7 extends survival following irradiation of brain tumours in mice and rats

Background:

In experimental models of glioblastoma multiforme (GBM), irradiation (IR) induces local expression of the chemokine CXCL12/SDF-1, which promotes tumour recurrence. The role of CXCR7, the high-affinity receptor for CXCL12, in the tumour''s response to IR has not been addressed.

Methods:

We tested CXCR7 inhibitors for their effects on tumour growth and/or animal survival post IR in three rodent GBM models. We used immunohistochemistry to determine where CXCR7 protein is expressed in the tumours and in human GBM samples. We used neurosphere formation assays with human GBM xenografts to determine whether CXCR7 is required for cancer stem cell (CSC) activity in vitro.

Results:

CXCR7 was detected on tumour cells and/or tumour-associated vasculature in the rodent models and in human GBM. In human GBM, CXCR7 expression increased with glioma grade and was spatially associated with CXCL12 and CXCL11/I-TAC. In the rodent GBM models, pharmacological inhibition of CXCR7 post IR caused tumour regression, blocked tumour recurrence, and/or substantially prolonged survival. CXCR7 expression levels on human GBM xenograft cells correlated with neurosphere-forming activity, and a CXCR7 inhibitor blocked sphere formation by sorted CSCs.

Conclusions:

These results indicate that CXCR7 inhibitors could block GBM tumour recurrence after IR, perhaps by interfering with CSCs.     

趋化因子受体CXCR5在肺癌中的表达及其意义

目的：探讨肺癌原发灶中趋化因子受体CXCR5的表达特点及与其临床病理的关系。方法：对79例肺癌手术切除标本组织采用免疫组化法检测CXCR5表达。结果：CXCR5在肺腺癌组织100％（46／46）中呈阳性表达,33例肺鳞癌中仅1例表达（3．0％）。CXCR5的表达与肺癌患者的性别、年龄、肿瘤大小无关（P〉0．05）,而与肺癌患者的组织学类型密切相关（P〈0．01）。结论：CXCR5表达与组织学类型密切相关。CX-CR5在肺腺癌选择性的表达值得进一步进行相关研究。