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1.

Background  

Advanced cancer is a multifactorial disease that demands treatments targeting multiple cellular pathways. Chinese herbal cocktail which contains various phytochemicals may target multiple dys-regulated pathways in cancer cells and thus may provide an alternative/complementary way to treat cancers. Previously we reported that the Chinese herbal cocktail Tien-Hsien Liguid (THL) can specifically induce apoptosis in various cancer cells and have immuno-modulating activity. In this study, we further evaluated the anti-metastatic, anti-angiogenic and anti-tumor activities of THL with a series of in vitro and in vivo experiments.  相似文献   

2.
Chemokines are a large group of low molecular weight cytokines that are known to selectively attract and activate different cell types. Although the primary function of chemokines is well recognized as leukocyte attractants, recent evidences indicate that they also play a role in number of tumor-related processes, such as growth, angiogenesis and metastasis. Chemokines activate cells through cell surface seven trans-membranes, G-protein-coupled receptors (GPCR). The role played by chemokines and their receptors in tumor pathophysiology is complex as some chemokines favor tumor growth and metastasis, while others may enhance anti-tumor immunity. These diverse functions of chemokines establish them as key mediators between the tumor cells and their microenvironment and play critical role in tumor progression and metastasis. In this review, we present some of the recent advances in chemokine research with special emphasis on its role in tumor angiogenesis and metastasis.  相似文献   

3.
Tissue invasion is an important determinant of angiogenesis and metastasis and constitutes an attractive target for cancer therapy. We have developed an assay to identify agents that inhibit invasion by mechanisms other than inhibition of cell attachment or cytotoxicity. A screen of marine sponge extracts identified motuporamines as micromolar inhibitors of invasion of basement membrane gels by MDA-231 breast carcinoma, PC-3 prostate carcinoma, and U-87 and U-251 glioma cells. Motuporamine C inhibits cell migration in monolayer cultures and impairs actin-mediated membrane ruffling at the leading edge of lamellae. Motuporamine C also reduces beta1-integrin activation, raising the possibility that it interferes with "inside-out" signaling to integrins. In addition, motuporamine C inhibits angiogenesis in an in vitro sprouting assay with human endothelial cells and an in vivo chick chorioallantoic membrane assay. The motuporamines show little or no toxicity or inhibition of cell proliferation, and they are structurally simple and easy to synthesize, making them attractive drug candidates.  相似文献   

4.
The efficacy of heparin (HEP), the heparin analogue hexuronyl hexosaminoglycan sulfate (HHS), and hydrocortisone (HC) was studied in inhibiting the growth of four morphologically distinct pancreatic adenocarcinoma lines (CBP, LHP2, LSP3, and Pour-LVG) in hamsters. Animals were inoculated with LD100 doses of one of the four tumor lines and were randomly allocated to groups of five animals, which received in their drinking water either: HEP (1000 U/ml) alone, HHS (10 mg/ml) alone, HC (0.5 mg/ml) alone, HEP plus HC, HHS plus HC, or no additives (control). Tumors were measured, growth rates calculated, and nonparametric statistical comparisons made among the median growth rates of all of the treatment groups. All four tumors were tested in the rabbit cornea assay for their ability to induce angiogenesis. Extracts of tumors from control animals as well as from animals treated with HHS plus HC were prepared for quantitative testing in vitro by endothelial cell migration assay. All four tumor lines caused angiogenesis as measured in the rabbit cornea assay. A reduction in median tumor growth rates was observed in animals treated with HHS plus HC bearing the CBP, Pour-LVG, and LSP3 tumors. Similarly, in vitro capillary endothelial cell migration was decreased by HHS plus HC treatment in animals bearing CBP, Pour-LVG, and LSP3 tumors. Animals bearing the LHP2 tumor showed no effect of HHS plus HC treatment on tumor growth rate and no effect on endothelial cell migration. HEP alone, HHS alone, HC alone, and HEP plus HC showed no effect on tumor growth rate in any of the four tumors tested.  相似文献   

5.
Angiogenesis and tumor metastasis depend on extracellular matrix (ECM) remodeling and subsequent cellular interactions with these modified proteins. An in-depth understanding of how both endothelial and tumor cells use matrix-immobilized cryptic ECM epitopes to regulate invasive cell behavior may lead to the development of novel strategies for the treatment of human tumors. However, little is known concerning the existence and the functional significance of cryptic laminin epitopes in regulating angiogenesis and tumor cell metastasis. Here, we report the isolation and characterization of a synthetic peptide that binds to a cryptic epitope in laminin. The STQ peptide selectively bound denatured and proteolyzed laminin but showed little interaction with native laminin. The cryptic laminin epitope recognized by this peptide was selectively exposed within malignant melanoma in vivo, whereas little if any was detected in normal mouse skin. Moreover, the STQ peptide selectively inhibited endothelial and tumor cell adhesion, migration, and proliferation in vitro and inhibited angiogenesis, tumor growth, and experimental metastasis in vivo. This inhibitory activity was associated with a selective up-regulation of the cyclin-dependent kinase inhibitor P27(KIP1) and induction of cellular senescence. These novel findings suggest the existence of functionally relevant cryptic laminin epitopes in vivo and that selective targeting of these laminin epitopes may represent an effective new strategy for the treatment of malignant tumors by affecting both the endothelial and tumor cell compartments.  相似文献   

6.
目的:研究APN抑制剂CIP-13F抗肿瘤侵袭转移及血管生成的作用机制,为药物开发和恶性肿瘤临床治疗奠定实验基础。方法:体外培养人卵巢透明细胞癌ES-2和人纤维肉瘤细胞HT-1080,应用L-亮氨酰对硝基苯胺底物法评价CIP-13F对APN酶活性的抑制作用,通过MTT比色评价CIP-13F对肿瘤细胞的生长抑制作用。以Transwell cham-ber法观察CIP-13F对ES-2细胞游走能力的抑制作用。体内建立Lewis肺癌自发性肺转移模型,分别给药后取肿瘤组织和肺组织,应用免疫组织化学法检测Lewis肺癌组织中APN的表达水平。以免疫组织化学法检测CD34表达水平评价肿瘤微血管密度(MVD)。结果:采用4、20、100和500μmol/L CIP-13F作用于ES-2和HT-1080细胞发现,对ES-2细胞,APN的表达和生长抑制作用呈现剂量-效应相关性,对HT-1080细胞中APN和生长抑制作用较弱。另外,不同浓度的CIP-13F与ES-2细胞穿过人工基底膜的能力呈剂量依赖性关系。100和500μmol/L的CIP-13F对肿瘤细胞穿过Matrigel的游走能力抑制率分别为42.0%和72.1%,P值分别为0.003和0.001。体内试验表明,Bestatin 100mg/kg组、CIP-13F50和100mg/kg剂量的肿瘤生长抑制率分别为33.2%、29.4%和45.8%(P值分别为0.013、0.020和0.005),同时,与阴性对照组相比,50和100mg/kg CIP-13F对Lewis肺癌肺转移抑制率分别为52.2%和81.3%(P值分别为0.001和0.000)。另外,50和100mg/kg CIP-13F作用下,Lewis肺癌组织的MVD值分别为18.6和14.9,与阴性对照组比较,MVD值均明显降低,P值分别为0.000和0.001。结论:环酰亚胺类肽化合物CIP-13F通过抑制APN活性,抑制肿瘤细胞的增殖和转移,进而抑制移植瘤鼠的腋部原发肿瘤灶的生长,降低肺继发转移灶的数目。CIP-13F用于治疗APN表达阳性的肿瘤有良好的应用前景。  相似文献   

7.
Inhibition of tumor growth and angiogenesis by soluble EphB4   总被引:6,自引:0,他引:6       下载免费PDF全文
EphB receptors and their ephrinB ligands play a key role in the formation of a regular vascular system. Recent studies have also shown the involvement of Eph/ephrin interactions in malignant tumor progression and angiogenesis. We have generated soluble monomeric EphB4 (sEphB4)-expressing A375 melanoma cells to study the effect of dominant negatively acting sEphB4 on tumor growth and angiogenesis. Soluble EphB4-expressing A375 tumors grown subcutaneously in nude mice show dramatically reduced tumor growth compared to control tumors. The proliferative capacity of sEphB4-expressing cells in monolayer culture is not altered. Yet, sEphB4-expressing A375 cells cannot establish proper cell-cell contacts in three-dimensional spheroids. However, sEphB4 transfectants have reduced proliferation and apoptosis rates when grown in three-dimensional culture in vitro or in subcutaneous tumors in vivo. Analysis of the vascular phenotype of the tumors revealed a reduction of intratumoral microvessel density in sEphB4-expressing tumors. Corresponding to these mouse experiments, a matched pair analysis of EphB4 and ephrinB2 expression in human colon carcinomas revealed significantly upregulated levels of EphB4 expression compared to adjacent normal tissue. Taken together, the data identify dual effects of sEphB4 on the tumor and the vascular compartment that collectively inhibit tumor growth.  相似文献   

8.
Xu Y  Liu YJ  Yu Q 《Cancer research》2004,64(17):6119-6126
Angiopoietins (Ang-1, Ang-2, and Ang-3) are the ligands of Tie-2 receptor tyrosine kinase. The essential roles of Ang-1 and Tie-2 in embryonic angiogenesis have been established, and studies have demonstrated the involvement of Ang-1 and Ang-2 in tumor angiogenesis. However, the role of Ang-3 in tumor angiogenesis and metastasis and the mechanism underlying its function are totally unknown. We have shown recently that Ang-3 is tethered on cell surface via heparan sulfate proteoglycans. In our current study, we have demonstrated that overexpression of Ang-3 inhibits pulmonary metastasis of Lewis lung carcinoma and TA3 mammary carcinoma (TA3) cells by inhibiting tumor angiogenesis and promoting apoptosis of the tumor cells. In addition, we have demonstrated that the binding of Ang-3 to the cell surface is required for the effective inhibition of Ang-3 on tumor metastasis and that Ang-3 inhibits endothelial cell proliferation and survival and blocks Ang-1- and vascular endothelial growth factor-induced activation of extracellular signal-regulated kinase 1/2 and Akt kinases, which likely underlie the Ang-3-mediated inhibition on tumor angiogenesis and metastasis.  相似文献   

9.
Antitumor and antimetastatic activity of the angiogenesis inhibitor O-(chloroacetyl-carbamoyl) fumagillol (TNP-470), a semisynthetic analogue offumagillin, was evaluated in breast cancer cell lines. In an in vitro MTTassay, after 72 hrs continuous exposure to TNP-470, growth inhibition wasobserved in all seven cell lines of murine (JYG-A, JYG-B, DD-762, andBALB/c-MC) or human (KPL-1, MDA-MB-231, and MKL-F) origin, in which the50% inhibitory concentrations (IC50) at 72 hrstreatment were 4.6, 4.4, 4.6, 10.1, 35.0, 25.3, and 33.4 µg/ml,respectively. In an in vivo assay using JYG-A, JYG-B, KPL-1, and MDA-MB-231cells by orthotopic (right thoracic mammary fat pad) transplantation infemale nude mice, TNP-470 at 30 or 50 mg/kg body weight was injected s.c.every other day from the day of tumor cell inoculation until the end of theexperiment. The inhibitory effect on primary tumor growth was obtained inall four cell lines in a dose-dependent manner. In the 50 mg/kgTNP-470-treated group, the reductions in tumor weight of the JYG-A, JYG-B,KPL-1, and MDA-MB-231 cells with respect to the controls were 50%,30%, 4%, and 49%, respectively. Metastasis was seen inthe JYG-A, JYG-B, and KPL-1 cells. The numbers of mice bearing pulmonarymetastases of JYG-A and JYG-B cells and regional axillary lymph nodemetastases of KPL-1 cells were reduced, and TNP-470 at the 50 mg/kg dose toKPL-1 cells significantly reduced lymph node metastases compared with thecontrol. Although the weight gain was retarded in the TNP-470-treated mice,weight loss was not seen. TNP-470 was highly effective in the treatment ofbreast cancer cells. These results suggest that the clinical use of TNP-470may be a promising treatment for breast cancer patients.  相似文献   

10.
大量研究证明肿瘤的生长和转移与肿瘤血管生成密切相关。血管周细胞作为血管组织的重要组成部分, 在血管新生以及维持血管稳定中发挥重要作用。作为一种血管周基质细胞, 血管周细胞能为血管提供结构支持以及通过影响血管稳定性来调整局部组织生理环境。尽管目前血管周细胞在癌症病理机制中的作用还不完全清楚, 但大量研究结果揭示血管周细胞-内皮细胞信号网络的失常对肿瘤血管生成和转移有重要意义。本文旨在评价关于血管周细胞在肿瘤病理机制方面的重要研究成果以及探讨潜在的抗癌治疗靶点。   相似文献   

11.
NAMI-A is a ruthenium-based compound with selective anti-metastasis activity in experimental models of solid tumours. We studied whether this activity was dependent on anti-angiogenic ability of NAMI-A. We thus investigated its in vitro effects on endothelial cell functions necessary for angiogenesis to develop, as well as its in vivo effects in the chick embryo chorioallantoic membrane model. Endothelial cell proliferation, chemotaxis, and secretion of the matrix-degrading enzyme metalloproteinase-2 were inhibited by NAMI-A in a dose-dependent manner, and without morphologic signs of cell apoptosis or necrosis. Lastly, NAMI-A displayed a dose-dependent in vivo anti-angiogenic activity in the chorioallantoic membrane model. These data suggest that the anti-angiogenic activity of NAMI-A can contribute to its anti-metastatic efficacy in mice bearing malignant solid tumours.  相似文献   

12.
The current therapy for prostate cancer includes radical prostatectomy, radiation therapy and hormonal ablation. Chemotherapy also provides beneficial results for some patients with advanced prostate cancer but with several harmful side effects. Hence there is a need to identify and develop alternate therapies, which can reduce the disease progression with minimal or few side effects. Earlier studies from our laboratory have shown that a Polyherbal mixture, Brahma Rasayna (BR) rich in anti-oxidant principles has a potential to be an anti-tumor agent. BR treatment of MAT-LyLu cell inoculated Copenhagen rats resulted in a decrease of palpable tumor incidence, delay in tumor occurrence and lower mean tumor volumes. Also, a significant reduction in tumor weight and lung metastasis was observed in BR treated animals in comparison to untreated controls. In the present study, we focused to examine the effect of BR on angiogenesis and regulation of molecular markers involved in angiogenesis using in-vivo and in-vitro models. BR treatment showed a significant reduction in Factor VIII expression compared to control indicating reduced angiogenesis. BR treated tumor specimens showed a decrease in the pro-angiogenic factors like VEGF, MMP-9 and MMP-2. Methanolic extract of BR was found to inhibit the proliferation, tube formation, cell migration and attachment of HUVEC on matrigel in a dose dependant manner. These findings suggest the possible mechanism(s) of action of BR in the reduction of tumor growth and metastatic spread.  相似文献   

13.
14.
血管生成与肿瘤的生长及转移   总被引:3,自引:0,他引:3  
新生血管既为肿瘤生长提供营养和氧气,也是肿瘤侵袭和转移的主要途径.宿主不能控制肿瘤血管生成,人为抑制血管生成能显著抑制肿瘤生长.血管生成抑制剂具有高效、低毒和不易产生耐药性的特点,抗血管生成疗法将成为不同于常规的新的肿瘤治疗策略.  相似文献   

15.
Although a considerable amount of effort has been placed on discovering the etiologies of cancer, the majority of the basic cancer research existing today has focused on understanding the molecular mechanism of tumor formation and metastasis. Metastatic spread of tumors continues to be a major obstacle to successful treatment of malignant tumors. Approximately 30% of those patients diagnosed with a solid tumor have a clinically detectable metastasis and for the remaining 70%, metastases are continually being formed throughout the life of the tumor. Even after the tumor is excised, the threat of death is attributable to the metastasis that may occur through the remaining tumor cells. In addition, treating the metastasis often proves futile since metastasis often vary in size, composition, and anatomical location. New treatments blocking the formation of metastasis will provide greater chances of survival for cancer patients. One family of enzymes that has been shown over the years to play a role in tumor progression is the matrix metalloproteinase (MMP) family. The main function of MMPs, also known as matrixins, is degradation of the extracellular matrix physiologic function involving MMPs include wound healing, bone resorption and mammary involution. MMPs, however, also contribute to pathological conditions including rheumatoid arthritis, coronary artery disease, and cancer. Tumor cells are believed to utilize the matrix degrading capability of these enzymes to spread to distant sites. In addition, MMPs also are thought to promote the growth of these tumor cells once they have metastasized. This review will discuss the role of MMPs and their inhibitors in tumor invasion, angiogenesis and metastasis with special emphasis on the gelatinases, MMP-2 and MMP-9.  相似文献   

16.
17.
Progress in molecular mechanisms of tumor metastasis and angiogenesis   总被引:16,自引:0,他引:16  
The development of metastases is the major cause of death for cancer patients, however, the mechanisms of tumor invasion and acquisition of capability to metastasize remain unclear. During the past decade, knowledge regarding the molecular and cellular processes involved in the regulation of tumor metastases has dramatically increased and has been focussed on cross-talk between selected cancer cells and the specific organ microenvironment. The three-step development of the invasive phenotype of cancer cells is described: cell attachment, local proteolysis and cell migration. The molecular analysis of invasion-associated cellular activities, mainly the role of homotypic and heterotypic cell-cell adhesions, cell-matrix interactions, proteolysis mechanisms and migration properties of cancer cells, are also discussed. The role of tumor phenotype and microenvironment in the metastatic predilection for a specific organ site is pointed out, considering the recent reports which indicate that the capacity to metastasize might be acquired early during multistep tumorigenesis, thereby also predicting the site of metastasis. In addition, this review summarizes the current knowledge regarding angiogenesis regulation in progressive tumor growth and in the complex, multistep nature of tumor cell dissemination. A better understanding of the linkage between genetic and epigenetic events in metastases development may result in new anticancer treatment strategies.  相似文献   

18.
神经纤毛蛋白-1(Neuropilin-1)最早是作为轴突导向分子collapsin/semaphorin的受体被发现,在神经发育过程中引导轴突选择正确途径以成功到达靶区,与此同时又可作为血管内皮生长因子受体-2(VEGFR-2)的共受体表达于血管内皮细胞,在血管新生中发挥作用。近来的研究表明NRP-1可通过依赖于VEGF和独立于VEGF的方式参与调节肿瘤血管新生,在肿瘤生长转移中发挥作用。  相似文献   

19.
20.
Laminin isoforms in tumor invasion,angiogenesis and metastasis   总被引:13,自引:0,他引:13  
Laminins are a growing family of alphabetagamma heterotrimeric proteins, commonly found in basement membranes (BMs). These large molecules promote cell adhesion and migration via integrins and other cell-surface receptors. Over 12 laminin isoforms are presently known. The various isoforms have a cell- and tissue-specific expression and are differentially recognized by integrins. Expression of laminin isoforms in tumors usually reflects expression in their normal counterparts. However, during tumor invasion, loss of the BM barrier occurs and a discontinuous pattern of laminin staining is observed. In carcinomas, tumor cells at the invading front strongly express intracellularly the gamma2 chain, a component of laminin-5. Remodeling of the vascular BM is observed during angiogenesis, and penetration of several BMs occurs during tumor dissemination and metastasis. Thus, disregulated cell-laminin interactions are major traits of malignant disorders.  相似文献   

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