肿瘤血管生成抑制剂研究进展

肿瘤生长、侵袭、转移和复发是血管生成依赖性的,以肿瘤血管生成的各个环节为靶点,研制血管生成抑制剂,可有效地抑制肿瘤的转移和复发,成为肿瘤防治的新途径.本文就目前已进入临床试验的30多种血管生成抑制剂研究进展作一综述.     

肿瘤血管生成抑制剂研究进展

肿瘤生长、侵袭、转移和复发是血管生成依赖性的,以肿瘤血管生成的各个环节为靶点,研制血管生成抑制剂,可有效地抑制肿瘤的转移和复发,成为肿瘤防治的新途径。本文就目前已进入临床试验的30多种血管生成抑制剂研究进展作一综述。     

血管生成与肿瘤的生长及转移

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.     

血管生成抑制剂在恶性肿瘤放射治疗中的作用

在肿瘤的生长和转移中，肿瘤血管的形成和生长起非常重要的作用。在1971年，Folkman在新英格兰医学杂志上首先提出了关于肿瘤血管形成以及通过抗血管形成抑制肿瘤生长的假说”。近年来，大量的实验数据表明，血管生成抑制剂可减少新血管的生成，从而使肿瘤生长延缓或退缩。人们开始尝试通过抗血管生成药物来治疗恶性肿瘤。[第一段]     

抗肿瘤血管生成及其基因治疗

Folkman于 1971年提出肿瘤的生长与转移依赖于血管生成,肿瘤细胞不仅通过肿瘤血管从宿主获得必需的营养和氧气并排出代谢产物,而且通过肿瘤血管向宿主输入大量的肿瘤细胞,导致肿瘤的不断生长和转移 . 抑制肿瘤血管生成,能显著抑制肿瘤的生长和转移 [1], 抗血管生成疗法是不同于常规疗法的新的肿瘤治疗策略,具有高效低毒和不易产生耐药性的特点 [2], 已成为当今肿瘤研究的热点 . 血管抑制剂的蛋白质疗法显著抑制了一系列实验性肿瘤的生长,但存在药物剂量偏高、重复给药、费用昂贵等缺点 . 基因治疗能有效克服上述缺点,是最有希望将抗血管生成疗法由动物实验应用到临床的途径之一 [1～3]. 近年来对肿瘤血管生成、血管抑制剂的开发,以及抗血管生成的基因治疗等方面的研究,已取得较大进展,综述如下 .     

沙利度胺治疗实体瘤的研究新进展

血管生成在实体瘤的生长、侵袭及转移方面发挥重要作用,以肿瘤血管生成的各个环节及其发生过程中的生化改变为靶点,研究血管生成抑制剂可以有效的抑制肿瘤生长、侵袭及复发.沙利度胺作为一种血管生成抑制剂,已经在治疗难治性多发性骨髓瘤方面取得良好的效果.本文简要综述其在实体瘤中应用的研究进展.     

肿瘤抗血管生成治疗研究进展

肿瘤的生长和转移有赖于血管生成。抗血管生成治疗以血管内皮细胞为靶向,通过对抗肿瘤血管生成,切断肿瘤的供养,从而遏制肿瘤的生长和转移,其方法主要包括抑制或中和血管生成因子、应用血管生成抑制剂和针对特异性标记物应用素或抗体攻击肿瘤血管内皮细胞,它具有高效性、特异性、不易产生耐药和毒副作用小等优点。迄今,包括Ｅｎｄｏｓｔａｔｉｎ和Ａｎｇｉｏｓｔａｔｉｎ在内的多种抗血管生成药物在抗肿瘤实验研究中取得良好效果,并已开始走向临床。     

血管生成抑制剂研究新进展

肿瘤生长与转移是血管生成依赖性的,抗肿瘤血管生成可致恶性肿瘤消退,而且低毒,不易产生获得性耐药。本文综述血管生成抑制剂治疗肿瘤的新进展。     

血管生成与肿瘤的生长及转移

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肿瘤治疗策略。     

内皮抑素及其抗肿瘤作用的研究进展

新生血管的形成（Angiogenesis）是肿瘤生长转移过程中的必要条件之一,它是一个多因素、多步骤的发展过程。因此控制血管生成己成为抑制肿瘤生长的重要途径之一。内皮抑素（Endostatin）是一种新发现的特异性血管内皮细胞增殖抑制剂,在血管生成过程中起负性调节作用。体外实验表明内皮抑素能有效抑制血管内皮细胞增殖、迁移及新生血管形成,是一种特异性的血管形成抑制剂,     

肿瘤血管生成与抗血管生成基因治疗

肿瘤血管生成是肿瘤生长浸润转移的关键步骤，其形成主要是促血管生成因子和抑制因子作用失衡的结果。以肿瘤血管生成为靶点的抗血管生成治疗作为肿瘤治疗新视野，已发展为重要的抗肿瘤策略。基因治疗则使抗血管生成治疗更具有靶向性，使这一治疗策略产生新的飞跃。本文就该领域研究情况作一综述。     

抗肿瘤血管生成治疗相关性研究

血管生成是肿瘤生长、侵袭、转移、和复发的基础。肿瘤血管生成是诸多因素共同作用的结果,其中血管生长刺激因子和血管生长抑制因子作用平衡与否,决定了血管生成是促进还是抑制。抗血管生成作为肿瘤治疗新方法,已成为重要的抗肿瘤策略。基因治疗则使抗血管生成治疗更具有靶向性。本文就该领域研究情况作一综述。     

Interferon-mediated anti-angiogenic therapy for neuroblastoma

Angiogenesis appears to be a fundamental requirement for tumor growth, invasion and metastasis. Evidence also exists to suggest that inhibition of tumor-associated angiogenesis can retard tumor growth and prevent tumor spread. Several naturally occurring angiogenesis inhibitors have been identified, including type I interferons (alpha/beta). These proteins are potent inhibitors of angiogenesis and may also have direct anti-tumor and immunomodulatory effects. Because anti-angiogenic therapy is likely cytostatic, long-term delivery of angiogenesis inhibitors may be required for the successful treatment of cancer. We have, therefore, explored the utility of a gene therapy-mediated approach for the delivery of interferon-beta and tested this approach, both alone and in combination with conventional chemotherapy, in murine models of neuroblastoma.     

Functional in vivo optical imaging of tumor angiogenesis, growth, and metastasis prevented by administration of anti-human VEGF antibody in xenograft model of human fibrosarcoma HT1080 cells

Angiogenesis plays a crucial role in cancer progression and metastasis. Thus, blocking tumor angiogenesis is potentially a universal approach to prevent tumor establishment and metastasis. In this study, we used in vivo and ex vivo fluorescence imaging to show that an antihuman vascular endothelial growth factor (VEGF) antibody represses angiogenesis and the growth of primary tumors of human fibrosarcoma HT1080 cells in implanted nude mice. Interestingly, administering the antihuman VEGF antibody reduced the development of new blood vessels and normalized pre-existing tumor vasculature in HT1080 cell tumors. In addition, antihuman VEGF antibody treatment decreased lung metastasis from the primary tumor, whereas it failed to block lung metastasis in a lung colonization experiment in which tumor cells were injected into the tail vein. These results suggest that VEGF produced by primary HT1080 cell tumors has a crucial effect on lung metastasis. The present study indicates that the in vivo fluorescent microscopy system will be useful to investigate the biology of angiogenesis and test the effectiveness of angiogenesis inhibitors. ( Cancer Sci 2009)     

血管生成抑制因子的研究进展

血管生成与肿瘤的生长、侵袭和转移密切相关,目前,以抑制血管生成为靶点治疗肿瘤有望成为抗肿瘤新疗法之一。近年来,研究发现了多种内源性血管生成抑制因子,其中一些已进入了临床试验阶段。本文对内源性血管生成抑制因子的结构、功能、作用机制及其在肿瘤治疗中的应用进行综述。     

Role of angiogenic factors of herbal origin in regulation of molecular pathways that control tumor angiogenesis

The formation of blood capillaries to sustain development and growth of new tissues is referred to as angiogenesis. Angiogenesis is pivotal in both carcinogenesis and metastasis since capillaries are the sole source of supplying nutrients and oxygen to the proliferating tumor cells; therefore, this dependency of tumor growth on angiogenesis challenges researchers to halt tumor growth by targeting angiogenesis with the help of either synthetic or natural inhibitors. Many synthetic inhibitors of angiogenesis have not only come into force but also resulted in some severe adverse effects. Natural compounds may effectively fit into this condition and possibly decrease the time of treatment. In the recent past, literature is replete with evidences advocating the usefulness of natural compounds that target multiple biochemical pathways. The additional advantage of natural compounds is that their active principles interact with one another and work synergistically to give more meaningful and reliable effects than individual principle. Hence, if we are somehow able to combine more than two natural compounds, then it may be possible to enhance their potential by many folds, which shall prove to be very effective in combating tumor angiogenesis. This review shall discuss the concept of angiogenesis, molecular pathways, and angiogenic inhibitors and their specific targets and potential of natural compounds to greatly enhance the current knowledge of angiogenesis-inhibiting factors.     

Recombinant PAI-1 inhibits angiogenesis and reduces size of LNCaP prostate cancer xenografts in SCID mice

To understand the fundamental determinants of urokinase plasminogen activator (uPA) driven angiogenesis in cancer we studied how inhibition of uPA activity could reduce neovascularization and consequently reduce tumor size in experimental animals. Proteolytic enzymes are required to mediate tumor cell invasion to adjacent tissues and initiate the metastatic process. Many different human cancers commonly overexpress the urokinase plasminogen activator system, one of the proteolytic enzyme systems. Reduction of urokinase activity in cancer cells is evidently associated with diminished invasion and metastasis. However, it has been shown recently that inhibitors of uPA could reduce tumor size also. The mechanism of action leading to decline in tumor growth rate is not clear. Proteolysis is responsible for degradation of proteins, for invasion or metastasis, but not for the proliferate properties of the cancer cells. It is difficult to envision that diminishing the size of tumor is due to simply blocking of uPA activity of cancer cells. Instead, inhibitors of uPA may be interacting with the elements of the extracellular matrix, such the neovascular bed surrounding tumors that has been reported to contain high amounts of uPA and its receptor. Overall these data strongly suggest that inhibitors of urokinase limit cancer growth by inhibiting angiogenesis. However, it is possible also that uPA inhibitors could act on cancer cells directly or prevent angiogenesis by alternative mechanisms that are not related to uPA inhibition. Therefore, we examined if plasminogen activator inhibitor (PAI-1) could limit angiogenesis. If it does, it will provide definitive evidence of uPA/PAI-1 involvement in reduction of cancer growth. Indeed, our study demonstrates that exogenously applied 14-1b PAI-1 is a powerful inhibitor of angiogenesis in three different in vitro models and is a powerful anti-cancer agent in a SCID mice model inoculated with human LNCaP prostate cancer cells.     

沙利度胺治疗实体瘤的研究新进展

血管生成在实体瘤的生长、侵袭及转移方面发挥重要作用,以肿瘤血管生成的各个环节及其发生过程中的生化改变为靶点,研究血管生成抑制剂可以有效的抑制肿瘤生长、侵袭及复发。沙利度胺作为一种血管生成抑制剂,已经在治疗难治性多发性骨髓瘤方面取得良好的效果。本文简要综述其在实体瘤中应用的研究进展。     

Angiogenesis inhibitorO-(chloroacetyl-carbamoyl) fumagillol (TNP-470) inhibits tumor angiogenesis,growth and spontaneous metastasis of MKL- 4 human breast cancer cells in female athymic nude mice

Accumulated knowledge regarding the important roles played by angiogenesis in solid tumor growth and metastasis has prompted the development of angiogenesis inhibitors for clinical use in cancer therapy. Among these inhibitors,O-(chloroacetyl-carbamoyl)fumagillol (TNP-470) has been reported to have both antitumor and antimetastatic activities in rodent and human tumor models. We recently established a new metastasis model of MKL-4 human breast cancer cells in female nude mice. This cell line is a co-transfectant of the MCF-7 cell line with genes of a potent angiogenic factor, fibroblast growth factor 4, and a genetic marker, bacteriallacZ. In this paper, we describe the inhibitory effects of TNP-470 on tumor angiogenesis, growth and metastasis in this MKL-4 metastasis model. Subcutaneous injection of 10 or 50 mg/kg of TNP-470 every other day for two weeks obviously inhibited the tumor growth and metastasis of MKL-4 cells in female nude mice. The treatment of TNP-470 at both doses significantly reduced the tumor volumes, respectively, to 28% and 14% of that in the control group (P<0.05 in each comparison). The positive rate of metastasis into the axillary lymph nodes was 100% in the control group, whereas it was only 3396 in both of the treatment groups. Distant metastasis into the inguinal lymph nodes, lungs, kidneys and liver also tended to decrease in both of the treatment groups. Immunohisto-chemical analysis using anti-factor VIII antibody revealed that the number of microvessels in both of the treatment groups was significantly less than that in the control group (P<0.01 in each comparison). To the best of our knowledge, this is the first report describing simultaneous demonstration of the antiangiogenic, antitumor and antimetastatic effects of TNP-470 on human breast cancer cells in nude mice. This work was supported in part by a grant from the Ministry of Education, Science and Culture of Japan and by a Research Project Grant (No. 5-3O4) from Kawasaki Medical School     

Indirubin inhibits tumor growth by antitumor angiogenesis via blocking VEGFR2-mediated JAK/STAT3 signaling in endothelial cell

Tumor angiogenesis is one of the hallmarks of the development in malignant neoplasias and metastasis. Many angiogenesis inhibitors are small molecules from natural products. Indirubin, the active component of a traditional Chinese herbal medicine, Banlangen, has been shown to exhibit antitumor and anti-inflammation effects. But its roles in tumor angiogenesis, the key step involved in tumor growth and metastasis, and the involved molecular mechanism is unknown. Here, we identified that indirubin inhibited prostate tumor growth through inhibiting tumor angiogenesis. Using chick chorioallantoic membrane (CAM) assay and mouse corneal model, we found that indirubin inhibited angiogenesis in vivo. We also showed the inhibition activity of indirubin in endothelial cell migration, tube formation and cell survival in vitro. Furthermore, indirubin suppressed vascular endothelial growth factor receptor 2-mediated Janus kinase (JAK)/STAT3 signaling pathway but had little effects on the activity of extracellular signal-regulated kinase (ERK) and p38 mitogen-activated protein kinase in endothelial cell. Our study provided the first evidence for antitumor angiogenesis activity of indirubin and the related molecular mechanism. Our investigations suggested that indirubin was a potential drug candidate for angiogenesis related diseases.