CCL19/21-CCR7生物学轴与肿瘤转移

肿瘤转移有其选择性和特异性,不同组织来源的肿瘤易向某些特定的组织和器官如淋巴结、肺、肝、骨等转移,但人们对其机制知之甚少。近年来,发现不少趋化因子及其受体在肿瘤的转移中扮演重要角色。现就CCL19/21-CCR7生物学轴在肿瘤转移中的作用作一综述。     

趋化因子受体与肿瘤转移

目前认为肿瘤细胞转移和淋巴细胞迁移具有相似机制,但趋化因子及其受体参与肿瘤转移的机制尚未完全阐明。由于其在肿瘤细胞器官选择性转移中的重要作用,趋化因子受体有希望成为肿瘤治疗的靶标并具有预后价值。现综述趋化因子受体与肿瘤侵袭和转移的研究进展。     

肿瘤微环境与趋化因子家族

肿瘤微环境中趋化因子及其受体在以下几个方面影响着肿瘤的生长与转移：调控免疫细胞向肿瘤组织的迁移；影响机体对肿瘤细胞的清除能力；调节肿瘤组织的血管新生；刺激肿瘤以自分泌或旁分泌形式产生生长分子；影响肿瘤细胞的浸润和转移。现综述近年来有关趋化因子及其受体与肿瘤细胞免疫逃逸，以及在肿瘤免疫治疗等方面的研究进展。     

肿瘤微环境与趋化因子家族

肿瘤微环境中趋化因子及其受体在以下几个方面影响着肿瘤的生长与转移调控免疫细胞向肿瘤组织的迁移;影响机体对肿瘤细胞的清除能力;调节肿瘤组织的血管新生;刺激肿瘤以自分泌或旁分泌形式产生生长分子;影响肿瘤细胞的浸润和转移.现综述近年来有关趋化因子及其受体与肿瘤细胞免疫逃逸,以及在肿瘤免疫治疗等方面的研究进展.     

趋化因子受体CCR7在骨肉瘤组织中的表达和临床意义

目的：研究 CCR7在人骨肉瘤组织中的表达情况,并探讨 CCR7表达与临床病理之间的关系。方法：收集临床50例骨肉瘤组织及20例骨软骨瘤组织,使用免疫组织化学方法检测其 CCR7的表达水平。结果：CCR7在骨肉瘤组织和骨软骨瘤组织中的阳性表达率分别为80．00％和15．00％。CCR7阳性表达和骨肉瘤肿瘤大小及转移密切相关（P ＜0．05）,而与年龄、性别、临床分期及组织学分型没有明显关系（P ＞0．05）。结论：骨肉瘤组织中 CCR7高表达预示着其在肿瘤增长和肿瘤转移可能起到一定的作用。因此 CCR7可能会成为临床上治疗骨肉瘤一个新的靶点。     

趋化因子及其受体与肿瘤

趋化因子及其受体在肿瘤的发生、生长和转移等各个阶段都有复杂的网络性表达，研究表明趋化因子CXCL12及受体CXCR4介导乳腺癌、结肠癌、膀胱癌和前列腺癌等肿瘤的转移和发展，这为深入探讨肿瘤的发病及转移机制提供了新视角。现对近年来有关趋化因子及其受体与肿瘤之间的研究进展作一综述。     

趋化因子与肿瘤侵袭转移

趋化因子是一类具有趋化作用的分泌型小分子蛋白质,其受体属于G蛋白偶联的7次跨膜受体超家族.越来越多的证据表明趋化因子与肿瘤生长、侵袭和转移密切相关.现综述趋化因子在肿瘤细胞增殖、迁移、粘附、降解细胞外基质、肿瘤血管生成及肿瘤器官特异性转移等过程中的作用.     

趋化因子及其受体与肿瘤

趋化因子及其受体在肿瘤的发生、生长和转移等各个阶段都有复杂的网络性表达,研究表明趋化因子CXCL12及受体CXCR4介导乳腺癌、结肠癌、膀胱癌和前列腺癌等肿瘤的转移和发展,这为深入探讨肿瘤的发病及转移机制提供了新视角。现对近年来有关趋化因子及其受体与肿瘤之间的研究进展作一综述。     

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CcR5在结肠癌中的表达及临床意义

目的 探究趋化因子受体CcR5在结肠癌中的表达及临床意义.方法 收集经结肠癌根治术切除且经病理学检查证实为结肠癌组织标本94例,选取50例距离肿瘤边缘>5 cm,且经病理学检查为正常的癌旁组织作为对照,采用实时定量PCR和免疫组化的方法,分别检测结肠癌组织和正常癌旁组织中CcR5的mRNA表达水平及阳性表达率,分析其与结肠癌临床病理学特征的关系.结果 结肠癌组织中CcR5 mRNA水平和阳性表达率明显高于正常癌旁组织的,差异具有统计学意义(P<0.05).CcR5 mRNA表达水平和阳性表达率与肿瘤大小、淋巴结转移、肝转移、TNM分期均有关,肿瘤大小>5 cm、出现淋巴结转移和肝转移、Ⅲ~Ⅳ期结肠癌患者CcR5的mRNA表达水平和阳性表达率均相应高于肿瘤大小≤5 cm、未发生转移、Ⅰ~Ⅱ期患者(P<0.05).LMVD与肿瘤大小、淋巴结转移、肝转移、TNM分期和分化程度有关.相关性分析结果显示,CcR5的mRNA表达水平与LMVD呈明显正相关(γ=0.9176,P=0.0099).结论 趋化因子受体CcR5的高表达与结肠癌发生、转移均有关,检测CcR5对于结肠癌的诊断和预测转移情况具有指导意义.     

Identification of genes potentially involved in bone metastasis by genome-wide gene expression profile analysis of non-small cell lung cancer in mice

Lung cancer is commonly associated with multi-organ metastasis, and the bone is a frequent metastatic site for lung cancer. However, the molecular mechanism of organ-specific metastasis remains poorly understood. To elucidate this issue, we analyzed in this study genome-wide gene expression profiles of 15 metastatic lesions from three organs (bone, lung and liver) in a mouse model with multi-organ metastasis properties of human non-small cell lung cancer cells (ACC-LC319/bone2), using a combination of laser-microbeam microdissection and DNA microarrays. We identified 299 genes that could potentially be involved in the organ-selective nature of lung cancer metastasis. Among them, 77 were bone-specifically expressed elements, including genes involved in cell adhesion, cytoskeleton/cell motility, extracellular matrix remodeling and cell-cell signaling as well as genes already known to be involved in the bone metastasis of breast cancers. Quantitative RT-PCR confirmed the specific upregulation of eight genes in bone metastasis tumors, suggesting that these genes may be involved in bone metastasis. Our findings should be helpful for a better understanding of the molecular aspects of the metastatic process in different organs, and could lead to molecular target-based anticancer drugs and prevention of metastasis, especially bone metastasis.     

Role of tumor cell adhesion and migration in organ-specific metastasis formation

To form clinically evident metastases--the main cause of death in cancer patients--, tumor cells (TC) must complete a highly complex series of steps called the metastatic cascade, including local invasiveness, intravasation, circulation, adhesion and extravasation, survival, proliferation and angiogenesis. Since failure of any one of these steps results in metastatic failure, understanding the metastatic cascade may guide us to new therapeutic concepts. Here we review the role of specific TC adhesion and migration processes for organ-selective metastasis formation. TC adhesion in the microvasculature of host organs is a specific and highly regulated process mainly mediated by selectins for TC/endothelial cell binding and by integrins for TC/extracellular matrix interactions. Defined expression of the adhesion molecules and their corresponding ligands in the host organs and on the TC governs organ-selective non-random TC arrest. TC motility and subsequent chemotactically guided extravasation of adherent cells is the second rate-limiting step in organ-specific metastasis formation. Only if cells have completed adhesion and extravasation the growth of micrometastases and finally clinically evident metastases can occur.     

Molecular correlates of site-specific metastasis

Metastasis is the spread of tumor cells from a primary site to distant organs. It is the major cause of cancer morbidity and death. In the last few decades, significant advances have been made in surgical techniques, radiation therapy delivery, and chemotherapy including the development of combination regimens and agents inhibiting newly characterized biological targets. Treatment of metastasis, however, remains the most challenging task in cancer therapy because metastatic growth relies on complex interactions between tumor cells and the host and is often resistant to all therapeutic modalities. Management of metastasis in bone is especially challenging given the difficulty of access for therapeutic agents. Contemporary research seeks to explain the striking organ specificity observed in metastasis. In this article, we will examine historic perspectives on site-specific metastasis and review cellular and molecular evidence pertinent to the mechanisms of organ specificity. We will discuss a number of studies that aim to identify gene signatures correlating with organ-selective metastasis using microarray technology. Lastly, we will discuss potential areas of future research including microRNAs, proteomics, and the development of diagnostic and therapeutic interventions.     

间质干细胞与肿瘤转移

间质干细胞(MSC)能够向炎症和肿瘤部位趋化,参与肿瘤微环境的组成,对肿瘤的生长和转移起重要作用.对间质干细胞在肿瘤生长与转移中的作用及机制研究将为肿瘤发生及肿瘤靶向治疗提供新的思路.     

大肠癌CD44V6、E-cadherin表达及临床意义

目的 :探讨大肠癌CD4 4 V6,E cadherin的表达对大肠癌的进展和转移的意义。方法 :应用SP免疫组化技术检测 56例大肠癌标本的CD4 4 V6,E cadherin的表达。结果 :CD4 4 V6表达有转移者 84 9%( 2 8/ 33) ,无转移者 39 1% ( 9/ 2 3)。E cadherin表达有转移者 2 4 2 % ( 8/ 2 3) ,无转移者 52 2 % ( 12 / 2 3) ,两者与肿瘤转移明显相关 (P <0 0 5)。结论 :对大肠癌组织进行CD4 4 V6,E cadherin的表达检测 ,有助于预测大肠癌的进展程度和转移的判断 ,以及评估预后     

Expression of CXC chemokine receptor-4 enhances the pulmonary metastatic potential of murine B16 melanoma cells

The chemokine receptors CC chemokine receptor (CCR) 7 and CXC chemokine receptor (CXCR) 4 have been implicated in cancer metastasis. To evaluate whether CXCR4 is sufficient to increase tumor metastasis in an organ-specific manner, we transduced murine B16 melanoma cells with CXCR4 (CXCR4-B16) and followed the metastatic fate of the transduced cells in both i.v. and s.c. inoculation models of metastasis. CXCR4-B16 cells demonstrated marked increases (>10-fold) in pulmonary metastasis compared with vector (pLNCX2)-B16 after i.v. and s.c. inoculation of tumor cells. The increase in metastasis could be completely inhibited by T22, a small peptide antagonist of CXCR4. As early as 24 and 48 h after i.v. injection, CXCR4-B16 cells were significantly increased in the lung compared with control B16 cells by 5- and 10-fold (P < 0.05), respectively. CXCR4-B16 cells adhered better to both dermal and pulmonary microvascular endothelial cells relative to control B16 cells. Moreover, CXCL12 promoted the growth of CXCR4-B16 cells in vitro. Whereas expression of CXCR4 in B16 cells dramatically enhanced pulmonary metastasis, metastasis to the lymph nodes, liver, and kidney was rare. Immunohistochemical staining of both primary human cutaneous melanoma and pulmonary metastases revealed CXCR4 expression. Thus, CXCR4 plays a potentially important role in promoting organ-selective metastasis, possibly by stimulating tumor adhesion to microvascular endothelial cells and by enhancing the growth of tumor cells under stress.     

Tumor-associated macrophages in cancers

Tumor-associated macrophages (TAMs) are major component of leukocytic infiltrate of tumors and play important roles in progression and regression of tumors. Tumor microenvironment determines the mutual conversion between M1 and M2 macrophages. In many kinds of tumors, M2 type macrophages are of the majority in TAMs and promote tumor progression and metastasis. The dynamic balance and interaction between TAMs and tumor cells have important effects on the occurrence and development of tumor. TAMs in malignant tumors are useful for clinical diagnosis and may provide a novel target for cancer treatment.     

骨桥蛋白与肝癌关系的研究进展

 近年来,骨桥蛋白（OPN）在肿瘤生长和转移中的作用引起人们广泛关注。现已发现在多种肿瘤中OPN能够促进肿瘤细胞的生长、转移,增强肿瘤细胞的黏附和迁移能力。在肝癌中,OPN尤其具备良好的诊断灵敏性和特异性,能够有效地判断肝癌患者预后,而抑制OPN表达能够抑制肝癌细胞生长与转移,提示该蛋白可能成为抗肿瘤药物的新靶点,具有潜在的临床应用前景。     

Crosstalk between breast cancer stem cells and metastatic niche: emerging molecular metastasis pathway?

Metastatic colonization represents the final step of metastasis, and is the major cause of cancer mortality. Metastasis as an “inefficient” process requires the right population of tumor cells in a suitable microenvironment to form secondary tumors. Cancer stem cells are the only capable population of tumor cells to progress to overt metastasis. On the other hand, the occurrence of appropriate microenvironmental conditions within the target tissue would be critical for metastasis formation. Metastatic niche seems to be the specialized microenvironment to support tumor initiating cells at the distant organ. Master regulators not only determine cancer stem cell state, but also may have regulatory roles in metastatic niche elements. Meanwhile, both cancer stem cell and metastatic niche may function like two sides of the metastatic coin. Hypoxia inducible factors have multiple roles in regulation of both sides of this coin. TGF-β superfamily, also, have been considered as master regulators of epithelial to mesenchymal transition and metastasis and may play crucial roles in regulation of metastatic niche as well. In this regard, we hypothesize the presence of a possible emerging molecular pathway in the biological process of breast cancer metastasis. In this process, non-Smad TGF-β-induced metastasis connects cancer stem cell and metastatic niche formation through a central path, “Metastasis Pathway”.     

Role of miR-10b in breast cancer metastasis

Ninety percent of cancer-related mortality is caused by metastasis. Current cancer treatments can control many primary tumors but rarely stop the metastatic spread. Accumulating evidence demonstrates that miRNAs are involved in cancer initiation and progression. Furthermore, several miRNAs have been found to regulate metastasis. In particular, recent studies provide the first functional evidence that overexpression of a specific miRNA, miR-10b, can contribute to the development of metastasis, which can be exploited therapeutically in treating breast cancer metastasis in mice. Further in-depth analysis should provide more precise evaluation of the roles, mechanisms, and therapeutic utility of this miRNA in breast cancer.