Angiogenesis, the formation of new blood vessels, is critical for tumor growth and metastasis. Notably, tumors themselves can lead to angiogenesis by inducing vascular endothelial growth factor (VEGF), which is one of the most potent angiogenic factors. Inhibition of angiogenesis is currently perceived as one of the most promising strategies for the blockage of tumor growth. In this study, we investigated the effects of Acer tegmentosum maxim water extract (ATME) on angiogenesis and its underlying signal mechanism. We studied the antiangiogenic activity of ATME by using human umbilical vein endothelial cells (HUVECs). ATME strongly inhibited VEGF-induced endothelial cell proliferation, migration, invasion, and tube formation, as well as vessel sprouting in a rat aortic ring sprouting assay. Moreover, we found that the p44/42 mitogen activated protein (MAP) kinase signaling pathway is involved in the inhibition of angiogenesis by ATME. Moreover, when we performed the in vivo matrigel plug assay, VEGF-induced angiogenesis was potently reduced when compared to that for the control group. Taken together, these results suggest that ATME exhibits potent antiangiogenic activity in vivo and in vitro and that these effects are regulated by the extracellular regulated kinase (ERK) pathway.
Acer/*metabolism ; Angiogenesis Inhibitors/*pharmacology ; Animals ; Cell Line, Tumor ; Cell Movement/drug effects ; Cell Proliferation/drug effects ; Cell Survival ; Extracellular Signal-Regulated MAP Kinases/*metabolism ; Hep G2 Cells ; Human Umbilical Vein Endothelial Cells/*drug effects ; Humans ; MAP Kinase Signaling System/drug effects ; Mice ; Mice, Inbred C57BL ; Mitogen-Activated Protein Kinase 1/metabolism ; Neoplasm Invasiveness/pathology ; Neovascularization, Pathologic/*drug therapy/prevention & control ; Nitric Oxide Synthase Type III/metabolism ; Phosphorylation/drug effects ; Plant Extracts/pharmacology ; Rats ; Rats, Sprague-Dawley ; Transcription Factors/metabolism ; Vascular Endothelial Growth Factor A/antagonists & inhibitors/metabolism

OBJECTIVETo investigate the mechanism of Panax notoginseng saponins (PNS), an effective component extracted from Panax notoginseng, on atherosclerotic plaque angiogenesis in atherosclerosis-prone apolipoprotein E-knockout (ApoE-KO) mice fed with high-fat, high-cholesterol diet.

METHODSTwenty ApoE-KO mice were divided into two groups, the model group and the PNS group. Ten normal C57BL/6J mice were used as a control group. PNS (60 mg/kg) was orally administered daily for 12 weeks in the PNS group. The ratio of plaque area to vessel area was examined by histological staining. The tissue sample of aortic root was used to detect the CD34 and vascular endothelial growth factor (VEGF) expression areas by immunohistochemistry. The expression of VEGF and nicotinamide adenine dinucleotide phosphate oxidase subunit 4 (NOX4) were measured by reverse transcription polymerase chain reaction and Western blotting respectively.

RESULTSAfter treatment with PNS, the plaque areas were decreased (P<0.05). CD34 expressing areas and VEGF expression areas in plaques were significantly decreased (P<0.05). Meanwhile, VEGF and NOX4 mRNA expression were decreased after treatment with PNS. VEGF and NOX4 protein expression were also decreased by about 72% and 63%, respectively (P<0.01).

CONCLUSIONPNS, which decreases VEGF and NOX4 expression, could alleviate plaque angiogenesis and attenuate atherosclerosis.

Animals ; Down-Regulation ; drug effects ; genetics ; Drugs, Chinese Herbal ; pharmacology ; Male ; Mice ; Mice, Inbred C57BL ; Mice, Knockout ; NADPH Oxidase 4 ; NADPH Oxidases ; genetics ; metabolism ; Neovascularization, Pathologic ; pathology ; prevention & control ; Panax notoginseng ; chemistry ; Plaque, Atherosclerotic ; pathology ; prevention & control ; Saponins ; pharmacology ; Vascular Endothelial Growth Factor A ; genetics ; metabolism

BACKGROUNDAngiogenesis is a prerequisite for tumor growth and plays an important role in rapidly growing tumors, such as malignant gliomas. A variety of factors controlling the angiogenic balance have been described, and among these, the endogenous inhibitor of angiogenesis, tumstatin, has drawn considerable attention. The current study investigated whether expression of tumstatin by glioma cells could alter this balance and prevent tumor formation.

METHODSWe engineered stable transfectants from human glioma cell line U251 to constitutively secrete a human tumstatin protein with c-myc and polyhistidine tags. Production and secretion of the tumstatin-c-myc-His fusion protein by tumstatin-transfected cells were confirmed by Western blotting analysis. In the present study, we identify the anti-angiogenic capacity of tumstatin using several in vitro and in vivo assays. Student's t-test and one-way analysis of variance (ANOVA) test were used to determine the statistical significance in this study.

RESULTSThe tumstatin transfectants and control transfectants (stably transfected with a control plasmid) had similar in vitro growth rates compared to their parental cell lines. However, the conditioned medium from the tumstatin transfected tumor cells significantly inhibits proliferation and causes apoptosis of endothelial cells. It also inhibits tube formation of endothelial cells on Matrigel. Examination of armpit tumors arising from cells overexpressing tumstatin repress the growth of tumor, accompanying the decreased density of CD31 positive vessels in tumors ((5.62 ± 1.32)/HP), compared to the control-transfectants group ((23.84 + 1.71)/HP) and wild type U251 glioma cells group ((29.33 + 4.45)/HP).

CONCLUSIONAnti-angiogenic gene therapy using human tumstatin gene may be an effective strategy for the treatment of glioma.

Animals ; Autoantigens ; genetics ; Brain Neoplasms ; blood supply ; therapy ; Cell Line, Tumor ; Cell Proliferation ; Collagen Type IV ; genetics ; Genetic Therapy ; Glioma ; blood supply ; pathology ; therapy ; Humans ; Mice ; Mice, Inbred BALB C ; Neovascularization, Pathologic ; prevention & control ; Platelet Endothelial Cell Adhesion Molecule-1 ; analysis ; Transfection

OBJECTIVETo investigate the therapeutic effect of thyroid hormone in nude mice bearing human pancreatic cancer xenograft.

METHODSA BALB/c nude mouse model bearing pancreatic cancer was established with human pancreatic cancer cell line Bx-PC3. The mouse models were divided randomly into 5 groups, namely the control group treated with distilled water, high and low concentrations of thyroid hormone (T3) groups, and high and low concentration of propylthiouracil (PTU) groups. After intervention for 21 days, the changes in body weight and xenograft tumor volume and weight were measured, and the serum T3 concentration was detected by ELISA assay. The expression of proliferating cell nuclear antigen (PCNA) and microvessel density (MVD) were detected using immunohistochemistry.

RESULTSThe body weight of nude mice in T3 groups was significantly reduced after intervention, while that in PTU groups showed no obvious changes. Compared with PTU groups and control group, T3 groups showed significantly reduced tumor volume and weight (P<0.05) with also reduced PCNA expression and MVD, but these effect did not exhibit a dose dependence (P>0.05).

CONCLUSIONThyroid hormone can inhibit the growth of human pancreatic cancer in nude mice by suppressing the proliferation and angiogenesis of the tumor cells, suggesting the potential value of thyroid hormone in pancreatic cancer therapy.

Animals ; Cell Line, Tumor ; Humans ; Male ; Mice ; Mice, Inbred BALB C ; Mice, Nude ; Microvessels ; pathology ; Neovascularization, Pathologic ; prevention & control ; Pancreatic Neoplasms ; blood supply ; pathology ; Proliferating Cell Nuclear Antigen ; metabolism ; Triiodothyronine ; pharmacology ; Xenograft Model Antitumor Assays

Sorafenib, the first oral multikinase inhibitor, can inhibit several kinases involved in tumor proliferation and angiogenesis including Raf, VEGFR, PDGFR, kit and so on. Due to the advantages of multi-mechanisms, broad-spectrum anticancer potency, and well-tolerated results in combination trials, more and more researchers have focused on the optimization of sorafenib in order to develop novel multi-targeted anticancer drugs. The present paper reviews the development of modification of sorafenib in recent years from two aspects: bio-isosterism and scaffold hopping. The structure-activity relationship (SAR) of these compounds is also summarized.
Animals ; Antineoplastic Agents ; chemical synthesis ; chemistry ; Cell Line, Tumor ; Humans ; Molecular Structure ; Neoplasms ; drug therapy ; pathology ; Neovascularization, Pathologic ; prevention & control ; Niacinamide ; analogs & derivatives ; chemical synthesis ; chemistry ; Phenylurea Compounds ; chemical synthesis ; chemistry ; Protein Kinase Inhibitors ; chemical synthesis ; chemistry ; Structure-Activity Relationship

Shikonin, the main active ingredient of Lithospermum, and its derivatives have been proved to have antitumor effects, and the anti-tumor mechanisms involve multiple targets. Based on recent literatures, this review focuses on the antitumor effects and its mechanisms. More emphases are given on the aspects of induction of apoptosis, induction of necrosis, acting on matrix metalloproteinase, acting on the protein tyrosine kinase and antiangiogenesis. The current status and problems of shikonin derivatives in antitumor effects are simply summarized and lookout for the development of antitumor drugs with shikonin as leading compounds.
Antineoplastic Agents, Phytogenic ; isolation & purification ; pharmacology ; therapeutic use ; Apoptosis ; drug effects ; Cell Line, Tumor ; Drugs, Chinese Herbal ; isolation & purification ; pharmacology ; therapeutic use ; Humans ; Lithospermum ; chemistry ; Matrix Metalloproteinase 9 ; metabolism ; Naphthoquinones ; isolation & purification ; pharmacology ; therapeutic use ; Necrosis ; Neoplasms ; drug therapy ; metabolism ; pathology ; Neovascularization, Pathologic ; prevention & control ; Plants, Medicinal ; chemistry ; Protein-Tyrosine Kinases ; metabolism ; Reactive Oxygen Species ; metabolism

Angiogenesis is critical and indispensable for tumor progression. Since VEGF is known to play a central role in angiogenesis, the disruption of VEGF-VEGF receptor system is a promising target for anti-cancer therapy. Previously, we reported that a hexapeptide (RRKRRR, RK6) blocked the growth and metastasis of tumor by inhibiting VEGF binding to its receptors. In addition, dRK6, the D-form derivative of RK6, retained its biological activity with improved serum stability. In the present study, we developed a serum-stable branched dimeric peptide (MAP2-dRK6) with enhanced anti-VEGF and anti-tumor activity. MAP2-dRK6 is more effective than dRK6 in many respects: inhibition of VEGF binding to its receptors, VEGF- and tumor conditioned medium-induced proliferation and ERK signaling of endothelial cells, and VEGF-induced migration and tube formation of endothelial cells. Moreover, MAP2-dRK6 blocks in vivo growth of VEGF-secreting colorectal cancer cells by the suppression of angiogenesis and the subsequent induction of tumor cell apoptosis. Our observations suggest that MAP2-dRK6 can be a prospective therapeutic molecule or lead compound for the development of drugs for various VEGF-related angiogenic diseases.
Amino Acid Sequence ; Angiogenesis Inhibitors/*pharmacology ; Animals ; Cell Movement/drug effects ; Cell Proliferation/drug effects ; Colorectal Neoplasms/*pathology/secretion ; Endothelial Cells/cytology/drug effects/enzymology ; Enzyme Activation/drug effects ; Extracellular Signal-Regulated MAP Kinases/metabolism ; Humans ; Mice ; Mice, Nude ; Molecular Sequence Data ; Neovascularization, Pathologic/pathology/prevention & control ; Neovascularization, Physiologic/drug effects ; Peptides/chemistry/*pharmacology ; Protein Multimerization/*drug effects ; Protein Stability/drug effects ; Rats ; Serum ; Vascular Endothelial Growth Factor A/*antagonists & inhibitors/secretion

Malignant tumor is the common disease that threaten severely to people's health. Formulae of traditional Chinese medicine (FTCM), as the major component of traditional drugs, has played more important role on the prevention and cure to tumor. The Folkman's theory that tumorous growth depends on tumor neovascularization has been confirmed so many years, so to inhibit the tumor angiogenesis, is an important path to treat tumor. The research of FTCM to antagonizing tumor angiogenesis in our country has been started more lately. Since it has been reported some FTCMs can inhibit angiogenesis, and it also exists many problems. The article summarized the correlated research of FTCM to antagonize tumor angiogenesis for the past several years, and according this, analyzed, stated and commented to the problems, countermeasures, development and direction of PTCM to antagonize tumor angiogenesis.
Animals ; Chemistry, Pharmaceutical ; Drugs, Chinese Herbal ; therapeutic use ; Humans ; Medicine, Chinese Traditional ; Neoplasms ; drug therapy ; pathology ; prevention & control ; Neovascularization, Pathologic ; drug therapy ; prevention & control

OBJECTIVEThis experiment aims to study the anti-angiogenic ability of vinorelbine combined with cetuximab in vitro and in vivo.

METHODSHuman lung adenocarcinoma A549 cells were used as control group. Proliferation of human umbilical vein endothelial cells (HUVEC) was assessed by MTT assay. Furthermore, we used Transwell chambers, capillary tube formation and flow cytometry to observe the effects of vinorelbine combined with cetuximab on HUVEC migration, tube formation and cell apoptosis, respectively. In addition, the anti-angiogenic ability of the drugs was checked using chicken chorioallantoic membrane (CAM) model.

RESULTSThe inhibitory rate of HUVEC growth was 25.8%, 39.2%, 54.0% for vinorelbine at the concentration of 0.1 ng/ml, 0.4 ng/ml, and 0.8 ng/ml, respectively; that of 0.25 microg/ml cetuximab was 19.7%, and that of 0.1 ng/ml vinorelbine + 0.25 microg/ml cetuximab, 0.4 ng/ml vinorelbine + 0.25 microg/ml cetuximab and 0.8 ng/ml vinorelbine + 0.25 microg/ml cetuximab was 29.5%, 46.4%, 64.6%, respectively. The inhibitory rates of the drugs at the above mentioned combinations of migration and tube formation of HUVEC were 51.9%, 68.2%, 95.0%, respectively. The inhibitory rate of 0.1 ng/ml + 0.25 microg/ml cetuximab and 0.4 ng/ml vinorelbine + 0.25 microg/ml cetuximab on tube formation of HUVEC was 38.8% and 57.7%, respectively, showing a sub-additive effect, and that of combination of 0.8 ng/ml vinorelbine + 0.25 microg/ml cetuximab was 78.9%, showing a synergistic effect. In addition, the apoptotic rate of HUVEC induced by 0.8 ng/ml vinorelbine + 0.25 microg/ml cetuximab was 59.9%, showing a synergistic effect. The in vivo experiment also showed that the combination of the two drugs had a synergistic anti-angiogenic effect.

CONCLUSIONBoth low dose vinorelbine and cetuximab have an anti-angiogenic effect in vitro and in vivo, and the combination of the two drugs has sub-additive or synergistic inhibitory effect on angiogenesis.

Adenocarcinoma ; blood supply ; pathology ; Angiogenesis Inhibitors ; pharmacology ; Animals ; Antibodies, Monoclonal ; pharmacology ; Antibodies, Monoclonal, Humanized ; Antineoplastic Agents ; pharmacology ; Antineoplastic Agents, Phytogenic ; pharmacology ; Apoptosis ; drug effects ; Cell Line, Tumor ; Cell Movement ; drug effects ; Cell Proliferation ; drug effects ; Cells, Cultured ; Cetuximab ; Chick Embryo ; Drug Synergism ; Endothelial Cells ; cytology ; Humans ; Lung Neoplasms ; blood supply ; pathology ; Neovascularization, Pathologic ; prevention & control ; Umbilical Veins ; cytology ; Vinblastine ; analogs & derivatives ; pharmacology

OBJECTIVETo study the anti-angiogenic effect of ginsenoside Rg3 (Rg3 in abbreviation) in human nasopharyngeal carcinoma HNE-1 cells in vitro.

METHODSThe tube-like structure (TLS) formation of HNE-1 cells, cultured in medium with different concentrations of Rg3, was determined by in vitro anti-angiogenic test based on preliminary experiment observing the TLSs formed by HNE-1 cells on Matrigel and their structural characteristics. The VEGF expression level in HNE-1 cells was determined by immunohistochemistry (IHC) and Western-blot test after 48-hour cultured in medium with different concentrations of Rg3.

RESULTSHNE-1 cells could form TLSs and mosaic vessels when mix-cultured with CRL-2480 on Matrigel. Rg3 could inhibit the TLS formation of HNE-1 cells. After 24-hour culture in medium with Rg3 at concentrations of 0, 50, 100 and 200 µg/ml, the number of TLSs were 75.50 ± 6.86, 55.00 ± 11.92, 39.75 ± 7.93 and 24.50 ± 6.25, respectively, which were negatively correlated with the concentrations of Rg3 (r = -0.928; P < 0.01). After 48 hours of culture, the expressions of VEGF significantly declined by IHC test with results as 0.19 ± 0.03, 0.13 ± 0.02, 0.11 ± 0.01, and 0.08 ± 0.01, respectively, which were negatively correlated with the concentrations of Rg3 (r = -0.911; P < 0.01). The expressions of VEGF also gradually decreased as revealed by Western blot test, with corresponding results as 119.49, 111.51, 86.45, and 38.29. All of the tests showed significantly declined results in the group at the concentration of 200 µg/ml Rg3.

CONCLUSIONRg3 can inhibit the vasculogenic mimicry of HNE-1 cells, and the possible mechanism might be associated with the down-regulation of VEGF protein expression in HNE-1 cells.

Angiogenesis Inhibitors ; administration & dosage ; pharmacology ; Carcinoma, Squamous Cell ; metabolism ; pathology ; Cell Line ; Cell Line, Tumor ; Coculture Techniques ; Dose-Response Relationship, Drug ; Down-Regulation ; Endothelial Cells ; cytology ; Ginsenosides ; administration & dosage ; pharmacology ; Humans ; Nasopharyngeal Neoplasms ; metabolism ; pathology ; Neovascularization, Pathologic ; prevention & control ; Umbilical Veins ; cytology ; Vascular Endothelial Growth Factor A ; metabolism