scholarly journals Epidermal growth factor stimulates vascular endothelial growth factor production by human malignant glioma cells: a model of glioblastoma multiforme pathophysiology.

1993 ◽  
Vol 4 (1) ◽  
pp. 121-133 ◽  
Author(s):  
C K Goldman ◽  
J Kim ◽  
W L Wong ◽  
V King ◽  
T Brock ◽  
...  

Hypervascularity, focal necrosis, persistent cerebral edema, and rapid cellular proliferation are key histopathologic features of glioblastoma multiforme (GBM), the most common and malignant of human brain tumors. By immunoperoxidase and immunofluorescence, we definitively have demonstrated the presence of vascular endothelial growth factor (VEGF) and epidermal growth factor receptor (EGFr) in five out of five human glioma cell lines (U-251MG, U-105MG, D-65MG, D-54MG, and CH-235MG) and in eight human GBM tumor surgical specimens. In vitro experiments with glioma cell lines revealed a consistent and reliable relation between EGFr activation and VEGF production; namely, EGF (1-20 ng/ml) stimulation of glioma cells resulted in a 25-125% increase in secretion of bioactive VEGF. Conditioned media (CM) prepared from EGF-stimulated glioma cell lines produced significant increases in cytosolic free intracellular concentrations of Ca2+ ([Ca2+]i) in human umbilical vein endothelial cells (HUVECs). Neither EGF alone or CM from glioma cultures prepared in the absence of EGF induced [Ca2+]i increases in HUVECs. Preincubation of glioma CM with A4.6.1, a monoclonal antibody to VEGF, completely abolished VEGF-mediated [Ca2+]i transients in HUVECs. Likewise, induction by glioma-derived CM of von Willebrand factor release from HUVECs was completely blocked by A4.6.1 pretreatment. These observations provide a key link in understanding the basic cellular pathophysiology of GBM tumor angiogenesis, increased vascular permeability, and cellular proliferation. Specifically, EGF activation of EGFr expressed on glioma cells leads to enhanced secretion of VEGF by glioma cells. VEGF released by glioma cells in situ most likely accounts for pathognomonic histopathologic and clinical features of GBM tumors in patients, including striking tumor angiogenesis, increased cerebral edema and hypercoagulability manifesting as focal tumor necrosis, deep vein thrombosis, or pulmonary embolism.

1995 ◽  
Vol 82 (5) ◽  
pp. 864-873 ◽  
Author(s):  
Jui-Chang Tsai ◽  
Corey K. Goldman ◽  
G. Yancey Gillespie

✓ Vascular endothelial growth factor/vascular permeability factor (VEGF/VPF) is an endothelial cell—specific mitogen that is structurally related to platelet-derived growth factor (PDGF). Vascular endothelial growth factor/vascular permeability factor induces angiogenesis in vivo and may play a critical role in tumor angiogenesis. Using immunohistochemical analysis, the authors demonstrated the presence of VEGF/VPF protein in surgical specimens of glioblastoma multiforme and cultured glioma cells. By means of an enzyme-linked immunosorbent assay (ELISA) of cell supernatants, the authors showed that VEGF/VPF is variably secreted by all nine cultured human malignant glioma cell lines (CH-235MG, D-37MG, D-54MG, D-65MG, U-87MG, U-105MG, U-138MG, U-251MG, U-373MG) and by a single meningioma cell line (CH-157MN). An immunocytochemical survey of these cell lines revealed a cytoplasmic and cell-surface distribution of VEGF/VPF. In the U-105MG glioma cell line, VEGF/VPF secretion was induced with physiological concentrations of epidermal growth factor, PDGF-BB, or basic fibroblast growth factor, but not with PDGF-AA. Moreover, it was observed that activation of convergent growth factor signaling pathways led to increased glioma VEGF secretion. Similar results were obtained using these growth factor combinations in the D-54MG glioma cell line. The data obtained suggest a potential role for VEGF/VPF in tumor hypervascularity and peritumoral edema. These observations may lead to development of new therapeutic strategies.


2005 ◽  
Vol 102 (6) ◽  
pp. 1055-1068 ◽  
Author(s):  
Roksana Rodak ◽  
Hisashi Kubota ◽  
Hideyuki Ishihara ◽  
Hans-Pietro Eugster ◽  
Dilek Könü ◽  
...  

Object. Taurolidine, a derivative of the amino acid taurin, was recently found to display a potent antineoplastic effect both in vitro and in vivo. The authors therefore initiated studies to assess the potential antineoplastic activity of taurolidine in human glioma cell lines and in ex vivo malignant cell cultures. They also studied the mechanisms that induce cell death and the impact of taurolidine on tumor-derived vascular endothelial growth factor (VEGF) production. Methods. Cytotoxicity and clonogenic assays were performed using crystal violet staining. In the cytotoxicity assay 100% of glioma cell lines (eight of eight) and 74% of ex vivo glioma cultures (14 of 19) demonstrated sensitivity to taurolidine, with a mean median effective concentration (EC50) of 51 ± 28 µg/ml and 56 ± 23 µg/ml, respectively. Colony formation was inhibited by taurolidine, with a mean EC50 of 7 ± 3 µg/ml for the cell lines and a mean EC50 of 3.5 ± 1.7 µg/ml for the ex vivo glioma cultures. On observing this high activity of taurolidine in both assays, the authors decided to evaluate its cell death mechanisms. Fragmentation of DNA, externalization of phosphatidylserine, activation of poly(adenosine diphosphate—ribose) polymerase, loss of the mitochondrial membrane potential followed by a release of apoptosis-inducing factor, and typical apoptotic features were found after taurolidine treatment. Cell death was preceded by the generation of reactive O2 intermediates, which was abrogated by N-acetylcysteine but not by benzyloxycarbonyl-Val-Ala-Asp-fluoromethylketone. Moreover, taurolidine also induced suppression of VEGF production on the protein and messenger RNA level, as shown by an enzyme-linked immunosorbent assay and by reverse transcription—polymerase chain reaction. Conclusions. Given all these findings, taurolidine may be a promising new agent in the treatment of malignant gliomas; it displays a combination of antineoplastic and antiangiogenic activities, inducing tumor cell apoptosis and inhibiting tumor-derived VEGF production.


2012 ◽  
Vol 03 (02) ◽  
pp. 93-92
Author(s):  
Alexander Kretzschmar

Vandetanib ist ein oraler Hemmer des RET-Kinase-, VEGF (Vascular Endothelial Growth Factor Receptor)- und EGFR (Epidermal Growth Factor Receptor)-Signalwegs. In einer zulassungsrelevanten, randomisierten, doppelblinden, placebokontrollierten Phase- III-Studie verlängerte der Tyrosinkinasehemmer das progressionsfreie Überleben (PFS) signifikant länger als Placebo.


2021 ◽  
Vol 6 (2) ◽  
pp. 236-241
Author(s):  
E. S. Pashinskaya ◽  

The purpose of the study is to study changes in gene expression in rat tissues during toxoplasmosis. Materials and methods. The experiment was conducted on 70 Wistar females weighing 170-220 grams. To achieve this goal, the expression of the proto-oncogenes survivin (BIRC5), epidermal growth factor (ErbB-2/HER2-Neu), GLI, vascular endothelial growth factor (VEGF) and anti-oncogene TP53 was determined in comparison with the reference genes β-actin (ACTB) and GAPDH by PCR analysis in the tissues of 10 healthy female rats and 60 infected with toxoplasma. RNA isolation was performed by the column method using the ReliaPrep RNA Cell Miniprep System (Promega Corporation, USA). The quality of the isolated RNA was evaluated spectrophotometrically. Reverse transcription was performed using M-MuLV RT (New England BioLabs Inc, USA). Primers specific to the genes were prepared using Primer3 and the NCBI Nucleotide database. Amplification was performed on a Real-Time PCR Detection System CFX96 thermal cycler (Bio-Rad, USA), using a qPCRmix-HS SYBR PCR mixture (Eurogen, Russia). Comparative expression of the studied genes was carried out after normalization of each of the samples to the level of the control genes GAPDH and ACTIN-β. Expression analysis was performed by qbase+ and CFX Maestro. Statistical processing of the obtained data was carried out using the program Statistica 10.0. Results and discussion. Toxoplasma increases the expression of survivin (BIRC5) in lung tissue to 0.013 relative units, in liver – to 0.038 relative units, in spleen – to 0.061 relative units, and in brain – to 0.050 relative units. VEGF expression in lungs increased to 0.034 relative units, in liver – to 0.041 relative units, in spleen – to 0.063 relative units, in brain tissues – to 0.080 relative units. There was an increase in the expression of ErbB-2/HER2-Neu in lung tissue to 0.436 relative units, in liver – to 0.259 relative units, in spleen – to 0.271 relative units, and in brain – to 0.131 relative units. GLI expression in lung tissues after toxoplasma infection increased to 0.113 relative units, in liver – to 0.188 relative units, in spleen – to 0.388 relative units, and in brain tissues – to 0.459 relative units. An increase in the expression of the anti-oncogene TP53 in the tissues of the lungs to 0.171 relative units, liver – to 0.295, spleen – to 0.408, and brain – to 0.259 relative units was revealed. Conclusion. It has been shown that toxoplasma can cause an increase in the expression of the proto-oncogenes survivin (BIRC5), epidermal growth factor (ErbB-2/HER2-Neu), GLI and vascular endothelial growth factor (VEGF) with simultaneous enhancement of the anti-oncogene TP53


Sign in / Sign up

Export Citation Format

Share Document