OBJECTIVETo study the expression and distribution of KDR, VEGF and CD34 in yolk sac and liver of human embryo at different development stage.

METHODSYolk sacs and livers of 15 human embryos were analyzed by the immunohistochemical SP kits for the expression of KDR, VEGF and CD34.

RESULTSKDR, VEGF and CD34 were all expressed in yolk sacs and livers of the embryos. In the intermediate liver group, the grey value of KDR and VEGF were 103.8 +/- 6.1 and 96.4 +/- 6.3, respectively, stronger than that in the late liver group which were 90.4 +/- 6.0 and 87.4 +/- 6.3, respectively (P < 0.05). A positive correlation between the levels of KDR and VEGF was observed (P < 0.05).

CONCLUSIONThe expression of KDR and CD34 in yolk sac and liver of embryo suggests the presence of hemangioblast in these organs. Interaction of KDR and VEGF might relate to survival, proliferation, migration and differentiation of hemangioblasts.

Embryo, Mammalian ; metabolism ; Humans ; Immunohistochemistry ; Liver ; embryology ; metabolism ; Vascular Endothelial Growth Factor A ; biosynthesis ; Vascular Endothelial Growth Factor Receptor-2 ; biosynthesis ; Yolk Sac ; metabolism

OBJECTIVETo investigate the correlation between the expression of the kinase insert domain-containing receptor (KDR) and the histological grade of prostate adenocarcinoma.

METHODSForty-eight samples of prostate adenocarcinoma tissues and 20 samples of benign prostatic hypertrophy (BPH) tissues were studied by LsAB immunohistochemical staining.

RESULTSThe positive expression rate of KDR was 73% in prostate adenocarcinoma and 30% in BPH. The expression of KDR was stronger in prostate adenocarcinoma, and there was no relationship between staining intensity and the histological grade of carcinoma.

CONCLUSIONKDR, expressed more highly in prostate adenocarcinoma, promises to be a new target in the treatment of prostate adenocarcinoma.

Adenocarcinoma ; metabolism ; Humans ; Male ; Prostatic Hyperplasia ; metabolism ; Prostatic Neoplasms ; metabolism ; Receptors, Vascular Endothelial Growth Factor ; biosynthesis ; Vascular Endothelial Growth Factor Receptor-2 ; biosynthesis

Bispecific antibodies have been exploited as both cancer immunodiagnostics and cancer therapeutics, which have shown promises in clinical trials in cancer imaging and therapy. To improve the anti-tumor effect, an scDb (bispecific single-chain diabody) was constructed from the variable domain genes of two scFvs (single-chain variable fragment antibodies) directed against human EGFR (epidermal growth factor receptor) and VEGFR2 (vascular endothelial growth factor receptor 2) extracellular domains. The anti-EGFR/ anti-KDR scDb was constructed into pHEN2 plasmid and expressed in Escherichia coli HB2151 host. After purification by one-step affinity chromatography of IMAC, scDb protein was characterized by Western blotting. The yield of scDb protein was 570 microg per liter medium. scDb bound to EGFR as efficiently as the parental antibody scFv-E10, while a little bit weaker than the parental antibody scFv-AK404R when bound to KDR. In conclusion, the scDb protein could bind both EGFR and KDR specifically and could be applied for further anti-tumor research.
Antibodies, Bispecific ; biosynthesis ; genetics ; Escherichia coli ; metabolism ; Humans ; Plasmids ; Protein Binding ; Receptor, Epidermal Growth Factor ; immunology ; Single-Chain Antibodies ; biosynthesis ; genetics ; Vascular Endothelial Growth Factor Receptor-2 ; immunology

OBJECTIVETo investigate the effect of rhodiola on expression of vascular endothelial growth factors receptors (VEGFR) in myocardium of rats after myocardial infarction.

METHODSOn the basis of successful establishment of myocardial infarction rat model, the experimental animals were divided into the model group, the rhodiola group, the positive control group and the sham-operated group, they were sacrificed after 6 weeks feeding. Their hearts were resected and embedded in paraffin to make sections with standard immunohistochemistry stain. Then the stained slices were analyzed in the IMS cell imagine analysis system using immunohistochemical quantitative analysis software. The field of vision of left ventricular myocardial tissue in three sites selected from the marginal area of infarction in each slice were determined, the mean value was then converted to positive area. Meanwhile, the mean optical density (OD) was calculated and the various expressions of VEGFR, i.e. Flt-1, KDR and angiopoietin receptor (Tie-2) were measured.

RESULTSThe expressions of Flt-1 and Tie-2 in myocardial tissue were significantly increased in the rhodiola treated group after treatment, showing significant difference as compared with those in the positive control group and the model group (P < 0.05). The expression of KDR in myocardium after rhodiola intervention was higher than that in the sham-operated and nonintervened group (P < 0.05), but insignificantly different to that in the positive control group and model group.

CONCLUSIONRhodiola could improve angiogenesis to ameliorate myocardial ischemia by regulating the expression of Flt-1 and Tie-2 in ischemic myocardium.

Animals ; Drugs, Chinese Herbal ; pharmacology ; Male ; Myocardial Infarction ; metabolism ; Myocardium ; metabolism ; Rats ; Rats, Sprague-Dawley ; Receptor, TIE-2 ; biosynthesis ; genetics ; Receptors, Vascular Endothelial Growth Factor ; biosynthesis ; genetics ; Rhodiola ; Vascular Endothelial Growth Factor Receptor-1 ; biosynthesis ; genetics ; Vascular Endothelial Growth Factor Receptor-2 ; biosynthesis ; genetics

OBJECTIVETo express granzyme B-vascular endothelial growth factor (VEGF) receptor-binding peptide (GrB-VRB) fusion protein in Bifidobacteria longum (B. longum) and investigate the effects of this fusion protein on the proliferation and apoptosis of cells expressing VEGF receptor II, the kinase domain receptor (KDR).

METHODSThe recombinant expression vectors pBBADx-VRB, pBBADx-GrB and pBBADx-GrB-VRB were separately transformed into B. longum cells by electroporation. The expressed products were identified by enzyme-linked immunosorbent assay and Western blotting, and their effects on KDR-positive cells were analyzed using proliferation assay and TUNEL assay.

RESULTSThe expressed products were detected in both the supernatant and cellular fractions of B. longum cells. The recombinant GrB-VRB fusion protein reacted with such KDR-positive cells as human umbilical vein endothelial cells (HUVEC) and mouse colon cancer cell line CT-26, and caused obvious cell proliferation inhibition, cytotoxicity and cell apoptosis in these cells.

CONCLUSIONThe recombinant GrB-VRB fusion protein secreted by the engineered B. longum cells can induce KDR-positive cell death as the result of GrB-induced cell apoptosis following the cell recognition by VRB.

Animals ; Apoptosis ; Bifidobacterium ; metabolism ; Carrier Proteins ; Cell Line, Tumor ; Cell Proliferation ; Granzymes ; metabolism ; Human Umbilical Vein Endothelial Cells ; Humans ; Mice ; Receptors, Vascular Endothelial Growth Factor ; metabolism ; Recombinant Fusion Proteins ; biosynthesis ; Vascular Endothelial Growth Factor Receptor-2 ; metabolism

OBJECTIVETo explore the effect of pro-angiogenic factors and their receptors on angiogenesis in hepatocellular carcinoma.

METHODSExpression of VEGF/KDR and Angiopoietins/Tie2 was detected by RT-PCR and Western blot in 15 cases with hepatocellular carcinoma, 15 tumor adjacent tissues (<1 cm, >5 cm), 8 cirrhotic liver, and 4 normal liver. Immunohistochemistry (IHC) was used to detect CD34 expression, and the relationship between neovascular density and angiogenesis was analyzed.

RESULTSThe expression levels of VEGF and Ang2 were significantly higher in hepacellular carcinoma group than those in the other groups (P < 0.01), and so did the expression of CD34. The expressions of KDR and Ang1/Tie2 showed no significant difference in all groups, but they indeed increased to various levels in tumor and tumor adjacent tissues as compared with those in cirrhosis and normal liver.

CONCLUSIONVEGF/KDR and Angiopoietins/Tie2 may be the crucial signal pathways in the development of hepatocellular carcinoma.

Adult ; Aged ; Angiopoietin-2 ; biosynthesis ; genetics ; Carcinoma, Hepatocellular ; metabolism ; pathology ; Humans ; Liver ; metabolism ; pathology ; Liver Neoplasms ; metabolism ; pathology ; Middle Aged ; Neovascularization, Pathologic ; RNA, Messenger ; biosynthesis ; genetics ; Receptor, TIE-2 ; biosynthesis ; genetics ; Signal Transduction ; Vascular Endothelial Growth Factor A ; biosynthesis ; genetics ; Vascular Endothelial Growth Factor Receptor-2 ; biosynthesis ; genetics

OBJECTIVETo investigate the expression and pattern of vascular endothelial growth factor (VEGF) and its fetal liver kinase-1 (Flk-1) receptor in spinal cord and dorsal root ganglia after neurotomy of sciatic nerve in rats.

METHODSForty-five adult male Wistar rats were divided randomly into a control group (n=5) and an experimental group (n=40). The bilateral sciatic nerves of the rats in the experimental group underwent neurotomy and the L4-L6 spinal cord and the corresponding dorsal root ganglia were harvested respectively at 8 hours, and 1, 3, 5, 7, 10, 14 and 21 days (8 subgroups with 5 rats each) after operation. The rats in the control group only underwent an exposure of sciatic nerve without neurotomy. Immunohistochemistry and image analysis were used to study the expression of VEGF and its Flk-1 receptor.

RESULTSBoth VEGF and Flk-1 receptor expressed in the normal rat spinal cord and dorsal root ganglia. In response to neurotomy, their expression reached a higher level and persisted for a short time then declined to the normal level rapidly. Besides, positive staining of Flk-1 was observed in both glial cells and nerve fibers, which located in the white matter of the spinal cord.

CONCLUSIONSVEGF can promote the regeneration of peripheral nerves from the angle of central neurons, which establishes the experimental and theoretical foundation for VEGF treating peripheral nerve injuries.

Analysis of Variance ; Animals ; Ganglia, Spinal ; metabolism ; Immunoenzyme Techniques ; Male ; Random Allocation ; Rats ; Rats, Wistar ; Sciatic Nerve ; metabolism ; surgery ; Vascular Endothelial Growth Factor Receptor-2 ; biosynthesis ; Vascular Endothelial Growth Factors ; biosynthesis

OBJECTIVETo evaluate the expression of vascular endothelial growth factor (VEGF) and its receptors KDR and Flt1 in patients with acute myeloid leukemia (AML).

METHODSThe expression of VEGF and its receptors mRNA was assayed by RT-PCR, the plasma of VEGF by ELISA.

RESULTSIn 13 AML cell lines, the expression of VEGF, KDR and Flt1 mRNA were found in 13 (100%), 7 (53.8%) and 12 (92.3%), respectively. There were 21 (65.6%), 1 (3.1%), and 17 (53.1%) of 31 (AML) patients bone marrow mononuclear cells (BMMNCs) expressing VEGF, KDR and Flt1 mRNA, respectively. None of BMMNCs from 3 normal donor and CD(34)(+) cells from 2 normal donor was found to express VEGF, KDR and Flt1 mRNA. The plasma level of VEGF of 39 patients (new diagnosed, relapsed and secondary-AML) before treatment was (135.3 +/- 87.9) ng/L which was significantly higher than that of 15 complete remission (CR) patients (80.6 +/- 36.9) ng/L and 12 normal donors (80.6 +/- 33.1) micro g/L (P = 0.028, 0.007). The plasma level of VEGF of 15 non-responsive patients was (188.2 +/- 118.6) ng/L after two cycles of chemotherapy which was higher than that of 20 CR patients [(104.2 +/- 30.9) ng/L] (P = 0.004).

CONCLUSIONVEGF and its receptors KDR and Flt1 mRNAs were expressed in BMMNCs of AML patients. The plasma level of VEGF directly affected the response to chemotherapy in AML patients.

Enzyme-Linked Immunosorbent Assay ; Humans ; Leukemia, Myeloid, Acute ; drug therapy ; metabolism ; RNA, Messenger ; genetics ; Reverse Transcriptase Polymerase Chain Reaction ; Vascular Endothelial Growth Factor A ; biosynthesis ; genetics ; Vascular Endothelial Growth Factor Receptor-1 ; biosynthesis ; genetics ; Vascular Endothelial Growth Factor Receptor-2 ; biosynthesis ; genetics

OBJECTIVETo study angiogenesis and regulatory factors in the proliferated prostatic tissues of Sprague Dawley (SD) rats with BPH induced by testosterone.

METHODSSixteen castrated SD rats, aged 8 weeks and weighing 200 approximately 250 g, were equally randomized into a model group and a control group, and the BPH model was established by subcutaneous injection of testosterone. Immunohistochemistry and MIAS (micro-image analysis system) were used to test the manifestations of MVD (microvessel density), VEGF (vascular endothelium growth factor), flk-1, endostatin, MMP-2 (matrix metalloproteinase-2) and TIMP-2 (tissue inhibitor of metalloproteinase-2) in the prostatic tissues of both the model and the control groups. Multiple linear regression with the stepwise method was adopted to analyze the data.

RESULTSThe manifestations of MVD, VEGF, flk-1, MMP-2, MMP-2/TIMP-2 and VEGF/endostatin in the model group were higher, while that of endostatin was lower than in the control group (P < 0.01), and the manifestation of TIMP-2 showed no statistical difference between the two groups. The regression analysis indicated that MVD was positively correlated to VEGF, VEGF/endostatin and MMP-2/TIMP-2 (r = 0.974, 0.986, 0.982, P < 0.05) and negatively correlated to endostatin (r = - 0.975, P < 0.05) .

CONCLUSIONTestosterone could induce BPH in SD rats by increasing MVD and promoting the multiplication of vascular endothelial cells after regradation of basement membrane.

Animals ; Disease Models, Animal ; Endostatins ; biosynthesis ; Male ; Matrix Metalloproteinase 2 ; biosynthesis ; Neovascularization, Pathologic ; chemically induced ; metabolism ; Prostate ; blood supply ; metabolism ; Prostatic Hyperplasia ; chemically induced ; metabolism ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Testosterone ; Tissue Inhibitor of Metalloproteinase-2 ; biosynthesis ; Vascular Endothelial Growth Factor A ; biosynthesis ; Vascular Endothelial Growth Factor Receptor-2 ; biosynthesis

Animals ; Bile Ducts ; cytology ; Cell Transdifferentiation ; Hepatocytes ; cytology ; Liver ; embryology ; metabolism ; Mice ; Mice, Inbred C57BL ; Vascular Endothelial Growth Factor Receptor-2 ; biosynthesis