表达Tie2的单核巨噬细胞在肿瘤微环境形成中的作用及机制研究进展

摘 要：表达Tie2的单核巨噬细胞（Tie2 expressing monocyte/macrophages,TEMs）是肿瘤相关巨噬细胞的重要亚群,存在于外周血、实体肿瘤等组织中。在肿瘤免疫抑制微环境中,TEMs能促进肿瘤生长、转移和复发,是肿瘤预后不良的新的指标,其作用机制主要通过促进血管生成、调节血管重塑、增加微血管密度、促进肿瘤微血管的形成;同时还可以抑制T细胞增殖、促进Treg的浸润、抑制抗肿瘤免疫应答。Ang-Tie2介导的Rheb/mTOR/p70S6K1信号通路是TEMs在肿瘤免疫微环境中促进肿瘤微血管生成的作用机制,对该细胞及相关通路的干预将成为新的肿瘤治疗靶点和策略。     

肿瘤相关巨噬细胞的研究进展

既往多认为,巨噬细胞是抗肿瘤免疫调节过程中的一种重要细胞群,可以直接杀伤肿瘤细胞,或者通过呈递肿瘤相关抗原诱导机体免疫应答从而清除肿瘤。但是近年来逐渐认识到,肿瘤间质中的巨噬细胞即肿瘤相关巨噬细胞(tumor-associated macrophages,TAM)并非发挥抗肿瘤作用,而是参与了肿瘤发生、生长、侵袭和转移的过程,尤其是与肿瘤血管生成和淋巴管生成密切相关。因此,研究TAM在肿瘤进程中的功能状态和动态变化具有重要意义,TAM有望成为肿瘤治疗的新靶点。1TAM的来源自从Rudolf Virchow首次发现肿瘤组织中有大量炎症细胞浸润后,有学者由此…     

结肠癌中肿瘤相关巨噬细胞与肿瘤浸润转移的关系

[目的]了解结肠癌组织中肿瘤相关巨噬细胞的浸润情况,探讨其与结肠癌侵袭转移的相关性。[方法]采用免疫组化染色的方法,对69例结肠癌标本中巨噬细胞的浸润情况进行检测,同时行巨噬细胞、淋巴管计数,并对巨噬细胞数量与临床病理参数之间的关系进行统计分析。[结果]结肠癌组织中有大量的肿瘤相关巨噬细胞浸润。结肠癌巨噬细胞计数与Duke’s分期有相关性(P=0.023),分期偏晚者巨噬细胞计数高于分期偏早者。巨噬细胞计数在年龄、性别、肿瘤分化程度等方面不存在差异(P>0.05)。巨噬细胞数量也与淋巴管数量相关(r=0.432,P<0.01)。[结论]结肠癌肿瘤组织中肿瘤相关巨噬细胞与淋巴管生成及肿瘤的侵袭转移有关。     

Tie2受体在直肠癌组织中的表达与调控作用

目的：探讨Tie2在直肠癌中的表达及其与血管生成的关系。方法：利用免疫组化S—P法，对40例直肠癌组织中的Tie2受体表达进行研究。结果：Tie2受体定位于癌组织中内皮细胞胞浆及胞核，部分癌细胞胞浆也存在阳性表达，直肠癌组织中的Tie2表达阳性率明显高于正常直肠组织（P〈0．05），Tie2受体的表达与临床病理中的分化程度、浸润深度、Dukes分期无关（P〉0．05），而与淋巴转移相关（P〈0．05）。结论：Tie2受体在直肠癌肿瘤组织的生成、分化、生长过程中具有重要调控作用。     

内皮细胞特异分子-1与人类肿瘤关系的研究进展

人内皮细胞特异分子-1(endothelial cell specific molecule-1,ESM-1)是一种可溶性的蛋白聚糖,由一条硫酸皮肤素链和一个核心蛋白相连而成。其基因位于人第五号染色体5q11.2上,含3个外显子和2个内含子。它的表达受细胞因子、血管生长因子、转录因子等多种因素的复杂调控。内皮细胞特异分子-1与人类多种肿瘤关系密切,可以促进肿瘤形成、生长和转移。其相关机制主要有促进细胞增殖、引起免疫抑制、促进淋巴管和血管生成等。它在肿瘤的筛查、诊断、治疗、疗效检测、预后判断等应用方面有着巨大的潜力,值得做更加广泛和深入的研究。     

巨噬细胞与肿瘤血管生成的研究进展

浸润到肿瘤组织内的巨噬细胞即肿瘤相关巨噬细胞(TAMs)。TAMs与肿瘤细胞共生,肿瘤细胞为TAMs提供存活因子,TAMs产生血管生成因子来响应肿瘤的微环境。本文综述了TAMs与血管生成的关系和在肿瘤发展过程中的作用,以及TAMs在肿瘤治疗中的作用。1巨噬细胞与肿瘤肿瘤一旦产生血管,就     

肿瘤相关巨噬细胞与肿瘤关系的研究进展

肿瘤相关巨噬细胞（ Tumor associate macrophages ,TAMs）是肿瘤的炎症微环境与肿瘤细胞间的重要信使。它是从血液中的单核细胞演变而来,主要通过集落刺激因子（ Colony -stimulating factor , CSF）趋化至肿瘤组织中。本文简述了TAMs通过影响血管生成和淋巴管生成,抑制免疫,调节基质,与干细胞相互作用等方面促进肿瘤的进展。分析表明靶向于TAMs的治疗策略是未来治疗肿瘤的一个新方向。     

肿瘤相关巨噬细胞对肿瘤新生血管生成的作用及其机制的研究进展

肿瘤相关巨噬细胞(TAM)在恶性肿瘤的发生、发展以及血管生成中发挥着重要作用.TAM被认为是肿瘤微环境(TME)的主要成分,具有促进肿瘤生长、侵袭、转移和肿瘤新生血管生成的作用.肿瘤基质中TAM的浸润水平、极化状态与患者预后密切相关,是肿瘤免疫治疗的潜在靶点.此外,肿瘤的生长依赖肿瘤新生血管生成,了解TAM在血管生成中...     

表达Tie2的单核细胞在肿瘤研究中的进展

表达Tie2的单核细胞(TEM)仅存在于外周血及肿瘤组织中,在肿瘤血管生成中发挥重要作用.TEM能够被血管生成素2(Ang2)及缺氧化学信号募集进入肿瘤组织,分化成表达Tie2的巨噬细胞,通过旁分泌作用参与肿瘤血管生成.肝癌、结肠癌、乳腺癌、恶性胶质瘤等肿瘤中检测到TEM水平升高,这对于肿瘤的诊断及预后判断有一定的提示作用.近年研究发现,TEM可用于抗肿瘤药物的靶向递送,能有效抑制肿瘤的生长和转移,同时TEM也是抗肿瘤治疗的潜在靶点.然而TEM在肿瘤微血管密度、临床分级及预后判断中的作用并不明确,目前针对TEM具体功能的探究引起了学者的广泛关注.     

Tek/Tie2 Signaling: New and Old Partners

A common property amongst angiogenic ligands such as the vascular endothelial growth factors and the angiopoietins is that they can elicit multiple responses depending upon the context of their expression and the presence of other growth factors. Study of the signal transduction pathways initiated by these growth factors provides insight into the molecular and cellular mechanisms that regulate vessel assembly. Key components of signal transduction cascades can then be used as potential targets in angiogenic therapies. This commentary reviews the recent advances into understanding the molecular signaling pathways mediated through the angiopoietin receptor, Tek/Tie2, as well as their effect on the regulation of distinct cellular aspects of angiogenesis.     

Enrichment of N-Cadherin and Tie2-bearing CD34/CD38/CD123 leukemic stem cells by chemotherapy-resistance

Acute myeloid leukemia (AML) arises from genetic changes at the level of stem cell, various mutations have been elucidated, including AML1–ETO fusion gene has been shown as the representative target of cellular transformation for LSCs originating from hematopoietic stem cells (HSCs) compartment. LSCs resemble HSCs with respect to self-renewal capacity and chemotherapy-resistance. However, LSCs possess specific cell-surface markers, they are proposed to reside within the CD34⁺/CD38⁻/CD123⁺ compartment. And the interaction mediated by adhesion molecules between LSCs and niche played a role in chemoresistance of LSCs. Therefore, study on the LSCs surface makers related to niche is helpful for the potential target therapy in the future. In this study, the proportions of CD34⁺/CD38⁻/CD123⁺ LSCs compartment co-expressing the three adhesion molecules, N-Cadherin, Tie2 and CD44, respectively, from AML patients before and after chemotherapy were analyzed. We demonstrated N-Cadherin and Tie2 positive CD34⁺/CD38⁻/CD123⁺ LSCs populations could be enriched by chemotherapy. Furthermore, AML1/ETO fusion signals and MDR1 expression were detected on the CD34⁺/CD38⁻/CD123⁺ LSCs populations expressing N-Cadherin and Tie2. Therefore, N-Cadherin and Tie2 are probably the potential markers for identification of LSCs.     

Tie2/TEK modulates the interaction of glioma and brain tumor stem cells with endothelial cells and promotes an invasive phenotype

Malignant gliomas are the prototype of highly infiltrative tumors and this characteristic is the main factor for the inevitable tumor recurrence and short survival after most aggressive therapies. The aberrant communication between glioma cells and tumor microenvironment represents one of the major factors regulating brain tumor dispersal. Our group has previously reported that the tyrosine kinase receptor Tie2/TEK is expressed in glioma cells and brain tumor stem cells and is associated with the malignant progression of these tumors. In this study, we sought to determine whether the angiopoietin 1 (Ang1)/Tie2 axis regulates crosstalk between glioma cells and endothelial cells. We found that Ang1 enhanced the adhesion of Tie2-expressing glioma and brain tumor stem cells to endothelial cells. Conversely, specific small interfering RNA (siRNA) knockdown of Tie2 expression inhibited the adhesion capability of glioma cells. Tie2 activation induced integrin β1 and N-cadherin upregulation, and neutralizing antibodies against these molecules inhibited the adhesion of Tie2-positive glioma cells to endothelial cells. In 2D and 3D cultures, we observed that Ang1/Tie2 axis activation was related to increased glioma cell invasion, which was inhibited by using Tie2 siRNA. Importantly, intracranial co-implantation of Tie2-positive glioma cells and endothelial cells in a mouse model resulted in diffusely invasive tumors with cell clusters surrounding glomeruloid vessels mimicking a tumoral niche distribution. Collectively, our results provide new information about the Tie2 signaling in glioma cells that regulates the cross-talk between glioma cells and tumor microenvironment, envisioning Tie2 as a multi-compartmental target for glioma therapy.     

促血管生成素１、２及Ｔｉｅ２受体ｍＲＮＡ在卵巢上皮性浆液性腺癌中的表达

目的：探讨卵巢上皮性浆液性腺癌中促血管生成素（Ａｎｇ）１、Ａｎｇ２及Ｔｉｅ２受体ｍＲＮＡ的表达及其临床意义。方法：采用逆转录聚合酶链反应（ＲＴ ＰＣＲ）分析４３例卵巢上皮性浆液性腺癌及１０例正常卵巢组织中Ａｎｇ１、Ａｎｇ２及Ｔｉｅ２受体的表达。结果：Ａｎｇ２ｍＲＮＡ在卵巢上皮性浆液性腺癌中表达明显上调（Ｐ＜０.００１）,并随着病情的进展其表达水平进一步提高（Ｐ＜０.００１）;卵巢上皮性浆液性腺癌中Ａｎｇ１ｍＲＮＡ的表达低于正常组织（Ｐ＜０.０５）,且与临床分期密切相关（Ｐ＜０.０５）;Ｔｉｅ２ｍＲＮＡ的表达量在腺癌与正常组织之间以及在腺癌的不同临床分期中差异无显著性（Ｐ＞０.０５）。结论：Ａｎｇ２的表达水平可能与卵巢上皮性浆液性腺癌的血管生成增强以及早期转移有关。     

脑星形细胞肿瘤中FAK、Pyk2表达及其与血管生成的关系

背景与目的：非受体酪氨酸蛋白激酶家族成员FAK和Pyk2具有高度同源性,对肿瘤细胞增殖和侵袭具有重要的调控作用,但其是否参与肿瘤血管生成过程尚不明确。本研究旨在探讨FAK和Pyk2在脑星形细胞肿瘤中表达与血管生成的关系。方法：应用免疫组化法检测58例脑星形细胞肿瘤中FAK、Pyk2和血管内皮生长因子（VEGF）表达,并用CD31标记计数瘤内微血管密度。结果：FAK、Pyk2蛋白主要表达于肿瘤细胞胞浆,Pyk2阳性表达也见于肿瘤血管内皮细胞。在Ⅰ、Ⅱ、Ⅲ、Ⅳ级星形细胞肿瘤中,FAK阳性率分别为20.0%（1/5）、26.7%（4/15）、44.4%（8/18）、50.0%（10/20）,Pyk2阳性率分别为40.0%（2/5）、60.0%（9/15）、77.8%（14/18）、85.0%（17/20）;FAK和Pyk2阳性表达强度评分在Ⅱ级星形细胞肿瘤与Ⅲ、Ⅳ级星形细胞肿瘤中具有显著差异性（P〈0.05）。FAK、Pyk2表达与VEGF和微血管密度呈正相关,相关系数分别为rs=0.423（P=0.001）和rs=0.729（P〈0.005）。结论：FAK、Pyk2可能通过与VEGF的相互作用而参与脑星形细胞肿瘤的血管生成过程。     

The HER-2/neu Oncogene in Tumors of the Gastrointestinal Tract

The HER-2/neu oncogene is localized to chromosome 17q and shares significant homology with the epidermal growth factor receptor. As a result of its potential role in the selection of therapy, HER-2/neu testing has reached near-standard-ofpractice status in breast cancer. There is considerable interest in HER-2/neu as a prognostic factor and target of therapy in tumors of the gastrointestinal tract. In this review of HER-2/neu expression in esophageal squamous cell carcinoma and adenocarcinomas of the esophagus, stomach, and colon, a wide range of expression of HER-2/neu from 0 to 83% likely reflects both differences in methods and reagents, as well as study bias associated with patient selection (i.e., early versus advanced disease). For esophageal squamous cell carcinoma, little information exists as to the prognostic significance of HER-2/neu expression. In adenocarcinoma associated with Barrett's esophagus there is contradictory data. However, most of the information available indicates that this marker has significant prognostic value. In gastric adenocarcinoma, the wide expression range may truly reflect patient selection because HER-2/neu positivity appears linked to advanced rather than early disease with limited invasion. The majority of studies favor a significant prognostic value of HER-2/neu status for this tumor. Finally, in colorectal cancer HER-2/neu overexpression also appears to be a significant adverse outcome indicator as judged by the current published literature. In conclusion, given that either HER-2/neu protein overexpression or gene amplification is associated with approximately one-fourth of all gastrointestinal tract malignancies, strategies designed to employ the marker in therapy selection appear warranted. During the next several years it will not be surprising to see these tumors treated with antiHER-2/neu modalities such as Herceptin^TM, likely in combination with other agents initially for patients with advanced disease, and possibly for individuals with high-risk lesions in an adjuvant setting.     

Macrophage-derived SHP-2 inhibits the metastasis of colorectal cancer via Tie2-PI3K signals

This research aimed to explore the influence of Src homology-2 containing protein tyrosine phosphatase (SHP- 2) on the functions of tyrosine kinase receptors with immunoglobulin and EGF homology domains 2 (Tie2)-expressing monocyte/macrophages (TEMs) and the influence of the angiopoietin(Ang)/Tie2-phosphatidylinositol-3-kinase (PI3K)/protein kinase B (Akt)/mammalian target of rapamycin (mTOR) (Ang/Tie2-PI3K/Akt/mTOR) signaling pathway on the tumor microvascular remodeling in an immunosuppressive microenvironment. In vivo, SHP-2- deficient mice were used to construct colorectal cancer (CRC) liver metastasis models. SHP-2-deficient mice had significantly more metastatic cancer and inhibited nodules on the liver surface than wild-type mice, and the high-level expression of p-Tie2 was found in the liver tissue of the macrophages’ specific SHP-2-deficient mice (SHP-2MACKO) + planted tumor mice. Compared with the SHP-2 wild type mice (SHP-2WT) + planted tumor group, the SHP-2MAC-KO + planted tumor group experienced increased expression of p-Tie2, p-PI3K, p-Akt, p-mTOR, vascular endothelial growth factor (VEGF), cyclooxygenase-2 (COX-2), matrix metalloproteinase 2 (MMP2), and MMP9 in the liver tissue. TEMs selected by in vitro experiments were co-cultured with remodeling endothelial cells and tumor cells as carriers. It was found that when Angpt1/2 was used for stimulation, the SHP-2MAC-KO + Angpt1/2 group displayed evident increases in the expression of the Ang/Tie2-PI3K/Akt/mTOR pathway. The number of cells passing through the lower chamber and the basement membrane and the number of blood vessels formed by cells compared with the SHP-2WT + Angpt1/2 group, while these indexes were subjected to no changes under the simultaneous stimulation of Angpt1/2 + Neamine. To sum up, the conditional knockout of SHP-2 can activate the Ang/Tie2-PI3K/Akt/mTOR pathway in TEMs, thereby strengthening tumor micro angiogenesis in the microenvironment and facilitating CRC liver metastasis.