Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027627 (metastases)
 103,950 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

An important critical point in tumor progression is the acquisition of metastatic potential. The presence of metastases in regional lymph nodes is an indicator of poor survival. The vascular endothelial growth factor (VEGF) family of growth factors and receptors is involved in vasculogenesis and angiogenesis. Among them, VEGF-C and VEGF-D regulate the lymphatic vessels development and growth via their binding to their receptor VEGFR3. The expression of VEGF-C or VEGF-D is demonstrated in various human tumors and can be used as pronostic factors in some of them. With the aid of these molecules and the discovery of specific lymphatic markers, lymphatic endothelial cells can be isolated and lymphatic vessels can be identified within tumors. The role of lymphangiogenesis in promoting the metastatic spread of tumor cells has been studied in animal models.
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PMID:[Mechanisms and role of lymphangiogenesis in cancer metastasis]. 1295

The expressions of VEGF-C mRNA, VEGFR-3 and CD31 were studied in order to investigate the correlation between them and neoangiogenesis, hyperplasia of micro-lymphatics and tumor metastases. 34 cases of prostate cancer tissue and 12 cases of adjacent nontumorous tissue specimens were tested. They were marked by VEGFR-3 and CD31 with immunohistochemistic staining and analyzed with image, the micro-lymphatics count (MLC) and microvessel density (MVD) were counted using Weidner's highest vessel density count method; the expression of VEGF-C mRNA was inspected in situ hybridization. The expression of VEGF-C mRNA was 44.12% positive in 34 cases of prostate cancer, the MLC (8.26 +/- 2.73)mm2 and MVD (74.82 +/- 11.76)mm2 in prostate cancer were significantly higher than those in adjacent nontumorous tissue (MLC, 4.82 +/- 3.48/mm2; MVD, 32.86 +/- 5.41/mm2). In addition, there was a correlation between the expression of VEGF-C mRNA and micro-lymphatics metastases and there was a positive correlation between the expression of VEGFR-3 and CD31. The expressions of VEGF-C mRNA , MLC, MVD in stage III and IV and those who have lymph metastasis were higher than those in stage I and II and those who have no lymph metastasis; the expressions of VEGFR-3 and CD31 in VEGF-C mRNA positive groups were significantly higher than those in negative groups. The difference of histopathologic grading in prostate cancer had no statistical significance. VEGF-C could accelerate the hyperplasia of micro-lymphatics and neoangiogenesis induced by tumor and play an important role in tumor lymph metastases. There was a close correlation between the expressions of VEGFR-3, CD31 and tumor metastases. The increase of MLC and MVD on prostate cancer indicated the hyperplasia of new micro-lymphatics and neoangiogenesis in the tumor tissue, which could also be a signal to determine the tumor metastases in clinic.
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PMID:[Correlation between the expression of VEGF-C mRNA, VEGFR-3, CD31 and tumor metastases in Chinese with prostate cancer]. 1604 20

Metastases are commonly found in the lymphatic system. The molecular mechanism of lymphatic metastasis is, however, poorly understood. Here we report that vascular endothelial growth factor (VEGF)-A stimulated lymphangiogenesis in vivo and that overexpression of VEGF-A in murine T241 fibrosarcomas induced the growth of peritumoral lymphatic vessels, which occasionally penetrated into the tumor tissue. As a result of peritumoral lymphangiogenesis, metastases in lymph nodes of mice were detected. VEGF-A-overexpressing tumors contained high numbers of infiltrating inflammatory cells such as macrophages, which are known to express VEGF receptor (VEGFR)-1. It seemed that in the mouse cornea, VEGF-A stimulated lymphangiogenesis through a VEGF-C/-D/VEGFR-3-independent pathway as a VEGFR-3 antagonist selectively inhibited VEGF-C-induced, but not VEGF-A-induced, lymphangiogenesis. Our data show that VEGF-A contributes to lymphatic mestastasis. Thus, blockage of VEGF-A-induced lymphangiogenesis may provide a novel approach for prevention and treatment of lymphatic metastasis.
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PMID:Vascular endothelial growth factor-a promotes peritumoral lymphangiogenesis and lymphatic metastasis. 1623 Mar 87

The lymphatic vascular system is necessary for the return of extravasated interstitial fluid and macromolecules to the blood circulation, for immune defense, and for the uptake of dietary fats. Impaired functioning of lymphatic vessels results in lymphedema, whereas tumor-associated lymphangiogenesis may contribute to the spread of cancer cells from solid tumors. Recent studies have identified lymphatic molecular markers and growth factors necessary for lymphangiogenesis. In particular, lymphatic endothelial receptor tyrosine kinase VEGFR-3, and its ligands VEGF-C and VEGF-D, are major players in promoting lymphatic vascular growth both during development and in pathological conditions. Lymphatic vessels play a crucial role in a variety of human cancers, since invasion of lymphatic vessels by tumor cells and subsequent development of lymph node metastases significantly influence the prognosis of cancer patients and, therefore, represent an integral part of tumor staging. Recent evidence on the important influence of lymphangiogenic growth factors on intralymphatic cancer growth and metastasis raises hopes that lymphatic vessels and factors inducing their growth could serve as additional targets for tumor therapy. Nevertheless, in contrast to blood vessel angiogenesis, the mechanisms of new lymphatic vessel formation in human cancers, i.e. lymphangiogenesis, are still relatively unclear. In the framework of possible antilymphangiogenic therapies, this review focuses on the mechanisms of lymphangiogenesis in general, and especially on the role of lymphatic vessels in the process of metastasis.
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PMID:Lymphangiogenesis, inflammation and metastasis. 1633 34

The VEGF/VPF (vascular endothelial growth factor/vascular permeability factor) ligands and receptors are crucial regulators of vasculogenesis, angiogenesis, lymphangiogenesis and vascular permeability in vertebrates. VEGF-A, the prototype VEGF ligand, binds and activates two tyrosine kinase receptors: VEGFR1 (Flt-1) and VEGFR2 (KDR/Flk-1). VEGFR1, which occurs in transmembrane and soluble forms, negatively regulates vasculogenesis and angiogenesis during early embryogenesis, but it also acts as a positive regulator of angiogenesis and inflammatory responses, playing a role in several human diseases such as rheumatoid arthritis and cancer. The soluble VEGFR1 is overexpressed in placenta in preeclampsia patients. VEGFR2 has critical functions in physiological and pathological angiogenesis through distinct signal transduction pathways regulating proliferation and migration of endothelial cells. VEGFR3, a receptor for the lymphatic growth factors VEGF-C and VEGF-D, but not for VEGF-A, regulates vascular and lymphatic endothelial cell function during embryogenesis. Loss-of-function variants of VEGFR3 have been identified in lymphedema. Formation of tumor lymphatics may be stimulated by tumor-produced VEGF-C, allowing increased spread of tumor metastases through the lymphatics. Mapping the signaling system of these important receptors may provide the knowledge necessary to suppress specific signaling pathways in major human diseases.
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PMID:Signal transduction by VEGF receptors in regulation of angiogenesis and lymphangiogenesis. 1633 62

Recent advances in understanding the biology of lymphangiogenesis, the new growth of lymphatic vessels, have cast new light on the molecular basis of metastasis to regional lymph nodes. The receptor tyrosine kinase VEGFR-3 is virtually exclusively expressed on lymphatic but not blood endothelium in the adult, and activation of VEGFR-3 by its ligands VEGF-C and VEGF-D is sufficient to induce lymphangiogenesis. Correlative studies with human tumors and functional studies using animal tumor models show that increased levels of VEGF-C or VEGF-D in tumors lead to enhanced numbers of lymphatic vessels in the vicinity of tumors, which in turn promotes metastasis to regional lymph nodes by providing a greater number of entry sites into the lymphatic system for invading tumor cells. These findings have prompted studies to investigate whether inhibitors of VEGFR-3 activation might represent novel therapeutic agents for the suppression of metastasis. However, a number of points regarding the therapeutic potential of anti-lymphangiogenic treatments in the context of cancer remain to be addressed. The spectrum and relative importance of molecules that induce lymphangiogenesis and the regulation of their expression during tumor progression, the reversibility of tumor-induced lymphangiogenesis, and possible side-effects of anti-lymphangiogenesis-based therapies all need to be investigated. Most importantly, the extent to which lymph node metastases contribute to the formation of metastases in other organs remains to be elucidated. These aspects are the focus of this review, and their investigation should serve as a roadmap to possible translational application.
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PMID:Tumor-induced lymphangiogenesis: a target for cancer therapy? 1649 4

Lymph nodes are the first site of metastases for most types of cancer, and lymph node status is a key indicator of patient prognosis. Induction of tumor lymphangiogenesis by vascular endothelial growth factor-C (VEGF-C) has been shown to play an important role in promoting tumor metastases to lymph nodes. Here, we employed receptor-specific antagonist antibodies in an orthotopic spontaneous breast cancer metastasis model to provide direct evidence for the key role of VEGFR-3 activation in metastasis. Inhibition of VEGFR-3 activation more potently suppressed regional and distant metastases than inactivation of VEGFR-2, although VEGFR-2 blockade was more effective in inhibiting angiogenesis and tumor growth. Despite prominent proliferation, metastases were not vascularized in any of the control and treatment groups, indicating that the growth of metastases was not dependent on angiogenesis at the secondary site for the duration of the experiment. Systemic treatment with either VEGFR-2 or VEGFR-3 antagonistic antibodies suppressed tumor lymphangiogenesis, indicating that VEGFR-3 signaling affects the rate of tumor cell entry into lymphatic vessels through both lymphangiogenesis-dependent and independent mechanisms. Combination treatment with the anti-VEGFR-2 and anti-VEGFR-3 antibodies more potently decreased lymph node and lung metastases than each antibody alone. These results validate the concept of targeting the lymphatic dissemination and thereby very early steps of the metastatic process for metastasis control and suggest that a combination therapy with antiangiogenic agents may be a particularly promising approach for controlling metastases.
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PMID:Inhibition of VEGFR-3 activation with the antagonistic antibody more potently suppresses lymph node and distant metastases than inactivation of VEGFR-2. 1751 Apr 38

Treatment options for ductal adenocarcinoma of the pancreas are limited by early lymphatic spread, but the lymphatic vessels in pancreatic carcinoma have not been studied to date. Here, we present a histomorphological analysis of lymphatic vessels in pancreatic cancer resection specimens. Both intratumoral and peritumoral tissue were devoid of active lymphangiogenesis. Intratumoral lymphatics were frequently collapsed and non-functional, whereas peritumoral lymphatic vessels were enlarged, and numerous lymphatic vessels were seen in metastases. In addition, we screened pancreatic cancer tissue and pancreatic carcinoma cell lines for mRNA expression of the lymphangiogenic growth factor, VEGF-C; its receptor, VEGFR-3/flt4; and Prox1, a transcription factor essential for embryonic development of both lymphatic vessels and the pancreatic bud. VEGF-C was abundantly expressed in pancreatic cancer tissue and -cell lines and VEGFR-3/flt4 was expressed in cancer stromal cells. Prox1 was strongly expressed in the normal exocrine pancreas but significantly reduced in pancreatic cancer specimens from patients with short survival rates. Well-differentiated cell lines displayed higher levels of Prox1 mRNA than poorly differentiated ones. These results suggest that active lymphangiogenesis is not required for lymphovascular spread of pancreatic cancer. VEGF-C may promote local tumor growth via paracrine signaling to stromal cells expressing VEGFR-3 and support the entry of cancer cells into peritumoral lymphatics. Furthermore, loss of Prox1 function may be a driving force behind pancreatic carcinoma progression.
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PMID:Role of lymphangiogenesis and lymphangiogenic factors during pancreatic cancer progression and lymphatic spread. 1652 37

Preclinical and clinical studies positively correlate the expression of vascular endothelial growth factor (VEGF)-C in tumors and the incidence of lymph node metastases. However, how VEGF-C regulates individual steps in the transport of tumor cells from the primary tumor to the draining lymph nodes is poorly understood. Here, we image and quantify these steps in tumors growing in the tip of the mouse ear using intravital microscopy of the draining lymphatic vessels and lymph node, which receives spontaneously shed tumor cells. We show that VEGF-C overexpression in cancer cells induces hyperplasia in peritumor lymphatic vessels and increases the volumetric flow rate in lymphatics at the base of the ear by 40%. The increases in lymph flow rate and peritumor lymphatic surface area enhance the rate of tumor cell delivery to lymph nodes, leading to a 200-fold increase in cancer cell accumulation in the lymph node and a 4-fold increase in lymph node metastasis. In our model, VEGF-C overexpression does not confer any survival or growth advantage on cancer cells. We also show that an anti-VEGF receptor (VEGFR)-3 antibody reduces both lymphatic hyperplasia and the delivery of tumor cells to the draining lymph node, leading to a reduction in lymph node metastasis. However, this treatment is unable to prevent the growth of tumor cells already seeded in lymph nodes. Collectively, our results indicate that VEGF-C facilitates lymphatic metastasis by increasing the delivery of cancer cells to lymph nodes and therapies directed against VEGF-C/VEGFR-3 signaling target the initial steps of lymphatic metastasis.
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PMID:Imaging steps of lymphatic metastasis reveals that vascular endothelial growth factor-C increases metastasis by increasing delivery of cancer cells to lymph nodes: therapeutic implications. 1691 83

The correlations between the expression of nm23H1 mRNA,VEGF-C mRNA, VEGFR-3 and neoangiogenesis, hyperplasia of micro-lymphatic, tumor metastases in gastric cancer were studied, the results supplied an experimental foundation for clinical treatment and prognosis. All the specimens were marked by VEGFR-3 antibody, the expressions of nm23H1 mRNA, VEGF-C mRNA were detected in 78 cases of gastric cancer in situ hybridization with EnVision and Leica-Qwin computer image analysis system. The Weidner's highest vessel density counting method was used to analyse micro-lymphatics count (MLC) of the specimens, and the patients' viability after operation was investigated. The positive expression of nm23H1 mRNA in gastric cancer was 69.23% (54 cases). There was negative correlation between the positive expression of nm23H1 mRNA and lymph node metastasizing, TNM staging, MLC (P < 0.01 or P < 0.05). The expression of VEGF-C mRNA was 46.15% (36 cases). It was positive related to the lymph node metastasis, TNM stages, MLC in gastric cancer (P < 0.01 or P < 0.05), and was significantly different compared with adjacent nontumorous tissue (P < 0.01 or 0.05). The expression of nm23H1 in stage I and II gastric cancer was high, while in stage III and IV the expression was lower or even none. The MLC (8.37 +/- 2.29/mm2) in gastric cancer was higher than that in adjacent nontumorous tissue (4.82 +/- 3.48/mm2), which has statistical significance (P < 0.05). There was negative correlation between the expression of nm23H1 mRNA and VEGFR-3 (p < 0.05, r = 0.8479), but positive correlation between VEGF-C mRNA and VEGFR-3 (P < 0.05, r = 0.8362). The MLC (10.82 +/- 2.51/mm2) in those who died in five years (48 cases) was higher than that (6.53 +/- 2.09/mm2) in those who were still alive, the difference has statistical significance (P < 0.05). In different tumor pathology grading, different differentiation, the nm23H1 positive expression is significantly different (P < 0.05). Higher the nm23H1 expressed, lower the tumor lymph metastasized, but the viability rate was higher, so the nm23H1 gene was thought to have the effect of suppressing gastric cancer occurring and lymph metastasizing. Higher the VEGF-C mRNA expressed, higher the tumor lymph metastasized, but the viability rate was lower. There is close correlation between the VEGFR-3 expression and gastric cancer lymph metastasizing. The higher MLC level indicated neoangiogenesis in gastric cancer. VEGF-C promote neoangiogenesis induced by tumor and play an important role in lymph metastasizing.
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PMID:[Study on the correlation between the expressions of nm23H1 mRNA, VEGF-C mRNA and lymphatic metastases, survival rate with gastric cancer]. 1694 71


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