This study was purposed to investigate the angiogenin (ANG) expression in COS-7 cells and its biological activity. The gene of angiogenin was obtained from mononuclear cells of peripheral blood by using RT-PCR and inserted into eukaryotic expression vector of pcDNA3.1. After being transfected into COS-7 cells, the recombinant ANG was identified by Western blot assay. The function of promoting proliferation of ANG to ECV304 cells was detected by MTT method, and its activity of vascularization was analyzed by chick embryo chorioallantois treated by the culture supernatant after transfection with pcDNA3.1-ang. The result showed that recombinant ANG was expressed in COS-7 cells after transfection for 24 to 36 hours. It could specifically react with monoclonal antibody against ANG. The recombinant ANG could obviously promote the proliferation of ECV304 cells. In contrast with the control group, the culture supernatant of pcDNA3.1-ang transfected group could stimulate the angiogenesis in embryo chorioallantois. It is concluded that the ang transiently expresses in COS-7 cells, and its expression product obviously stimulates the cell proliferation and angiogenesis.
Angiogenesis Inducing Agents ; pharmacology ; Animals ; COS Cells ; metabolism ; Cell Line ; Cell Proliferation ; drug effects ; Cercopithecus aethiops ; Endothelial Cells ; cytology ; Genetic Vectors ; genetics ; Humans ; Recombinant Fusion Proteins ; biosynthesis ; genetics ; pharmacology ; Ribonuclease, Pancreatic ; biosynthesis ; genetics ; pharmacology ; Transfection

PURPOSE: To investigate the properties of angiogenin (ANG) as a potential tool for the diagnosis and grading of dry eye syndrome (DES) by analyzing tear protein profiles. METHODS: Tear samples were collected with capillary tubes from 52 DES patients and 29 normal individuals as controls. Tear protein profiles were analyzed with an immunodot blot assay as a screening test. To confirm that the tear ANG levels were in inverse proportion to the disease severity grade, the ANG and lactoferrin (LF) tear contents of normal controls and DES patients were compared in an enzyme-linked immunosorbent assay. RESULTS: In the immunodot blot assay, the ANG area was lower in patients with grades 3 and 4 DES than in normal controls. The areas of basic fibroblast growth factor, transforming growth factor β2, and interleukin 10 were significantly greater than those of normal controls only in grade 4 DES patients, but these proteins were not linearly correlated with dry eye severity. Upon enzyme-linked immunosorbent assay analysis, the mean concentrations of ANG and LF decreased significantly as dry eye severity increased, except between grades 1 and 2. In addition, the ratios of ANG and LF to total tear proteins were correlated significantly with DES severity. CONCLUSIONS: ANG level was significantly lower in DES patients than in normal controls, and was significantly correlated with the worsening severity of DES, except between grades 1 and 2, as was LF. Therefore, ANG may be a useful measure of DES severity through proteomic analysis.
Adult ; Aged ; Angiogenesis Inducing Agents/pharmacology ; Dry Eye Syndromes/*diagnosis/metabolism ; Enzyme-Linked Immunosorbent Assay ; Female ; Follow-Up Studies ; Humans ; Immunoblotting ; Male ; Middle Aged ; Proteomics/methods ; Ribonuclease, Pancreatic/*pharmacology ; Severity of Illness Index ; Tears/chemistry ; Young Adult

Angiostatin is a potent angiogenesis inhibitor that is composed of the first four kringles of plasminogen fragment. Angiostatin with one less kringle molecule (kringle 1 to 3) was recently demonstrated to be an effective angiogenic inhibitor. To determine whether recombinant plasminogen kringle 1-3 (rPK1-3) can inhibit the corneal neovascularization induced by potent angiogenic factors; angiogenin, bFGF, or VEGF, hydron polymer discs each containing 2.0 microg of angiogenin, 500 ng of bFGF, or 500 ng of VEGF respectively were implanted into the corneal stroma of 138 rabbit eyes, and then discs each containing 10 microg, 12.5 microg, 20 microg or 30 microg of rPK1-3 were implanted randomly. Discs containing phosphate buffered saline were also implanted as a control. The angiogenesis score on number and length of newly formed vessels on the each of the rabbit's cornea were recorded daily by two observers (blinded). The treated corneas were also examined histologically. Recombinant PK1-3 treated corneas showed less neovascularization induced by all angiogenic factors (p < 0.05). and the extent of inhibition of neovascularization was proportional to the concentration of rPK1-3 (p < 0.05). Histologic examination showed leukocyte infiltration into the corneal stroma on the PBS treated eyes whereas rPK1-3 treated eyes showed only traces of leukocytes. These results of the effective rPK1-3 inhibition of corneal neovascularization induced by angiogenin, bFGF, or VEGF suggest that this angiostatin related fragment, rPK1-3, may be useful in the treatment of various neovascular diseases. Copyright 2000 Academic Press.
Angiogenesis Inhibitors/pharmacology* ; Angiogenesis Inhibitors/genetics ; Animal ; Chick Embryo ; Chorion/drug effects ; Chorion/blood supply ; Cornea/pathology ; Cornea/drug effects ; Cornea/blood supply* ; Endothelial Growth Factors/pharmacology ; Fibroblast Growth Factor, Basic/pharmacology ; Kringles/genetics ; Lymphokines/pharmacology ; Microscopy/methods ; Neovascularization, Pathologic/drug therapy* ; Plasminogen/pharmacology* ; Plasminogen/genetics* ; Rabbits ; Recombinant Proteins/pharmacology ; Recombinant Proteins/genetics ; Ribonuclease, Pancreatic/pharmacology

Neamine, a non-toxic derivative of neomycin, has recently been shown to have antitumor activities in various types of cancers. However, its effect on pancreatic cancer is still unknown. The study aimed to investigate its antitumor activity on pancreatic cancer and the underlying mechanisms. MTT assay was used to observe the effect of neamine on angiogenin (ANG)-induced AsPC-1 cell proliferation. Tissue microassay and immunofluorescence staining were used to detect the expression of ANG and its nuclear translocation, respectively. Tumor xenografts were established by subcutaneous inoculation of AsPC-1 pancreatic cancer cells into the right flanks of nude mice, and neamine was injected subcutaneously. Immunohistochemistry was done to observe the expression of ANG, CD31 and Ki-67 in tumor xenografts. It was found that neamine blocked the nuclear translocation of ANG effectively and inhibited ANG-induced AsPC-1 cell proliferation in a dose-dependent manner. Neamine had anti-tumor effects on AsPC-1 xenograft models. Consistently, neamine reduced the expression levels of ANG, Ki-67 and CD31 in tumor xenografts. It was concluded that neamine may be a promising agent for treatment of pancreatic cancer.
Adult ; Animals ; Antibiotics, Antineoplastic ; pharmacology ; therapeutic use ; Carcinoma ; drug therapy ; Cell Line, Tumor ; Cell Proliferation ; drug effects ; Framycetin ; pharmacology ; therapeutic use ; Humans ; Ki-67 Antigen ; genetics ; metabolism ; Male ; Mice ; Mice, Inbred BALB C ; Mice, Nude ; Middle Aged ; Pancreatic Neoplasms ; drug therapy ; Platelet Endothelial Cell Adhesion Molecule-1 ; genetics ; metabolism ; Ribonuclease, Pancreatic ; genetics ; metabolism