262 poster Induction of vascular endothelial growth factor (VEGF) by ionizing radiation and effect of VEGF on radiation-induced apoptotic cell death in human malignant glioma cell lines

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.

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

Molecular Biology of the Cell ◽

10.1091/mbc.4.1.121 ◽

1993 ◽

Vol 4 (1) ◽

pp. 121-133 ◽

Cited By ~ 339

Author(s):

C K Goldman ◽

J Kim ◽

W L Wong ◽

V King ◽

T Brock ◽

...

Keyword(s):

Vascular Endothelial Growth Factor ◽

Growth Factor ◽

Cell Lines ◽

Glioma Cell ◽

Cellular Proliferation ◽

Glioma Cells ◽

Vascular Endothelial ◽

Glioma Cell Lines ◽

Epidermal Growth ◽

Endothelial Growth Factor

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.

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Vascular endothelial growth factor in human glioma cell lines: induced secretion by EGF, PDGF-BB, and bFGF

Journal of Neurosurgery ◽

10.3171/jns.1995.82.5.0864 ◽

1995 ◽

Vol 82 (5) ◽

pp. 864-873 ◽

Cited By ~ 173

Author(s):

Jui-Chang Tsai ◽

Corey K. Goldman ◽

G. Yancey Gillespie

Keyword(s):

Vascular Endothelial Growth Factor ◽

Growth Factor ◽

Cell Line ◽

Cell Lines ◽

Glioma Cell ◽

Glioma Cell Line ◽

Vascular Endothelial ◽

Vascular Permeability Factor ◽

Glioma Cell Lines ◽

Endothelial Growth Factor

✓ 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.

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Increased expression of adenosine 2A receptors in metastatic renal cell carcinoma is associated with poorer response to anti-vascular endothelial growth factor agents and anti-PD-1/Anti-CTLA4 antibodies and shorter survival

Cancer Immunology Immunotherapy ◽

10.1007/s00262-020-02843-x ◽

2021 ◽

Author(s):

Takao Kamai ◽

Toshiki Kijima ◽

Toyonori Tsuzuki ◽

Akinori Nukui ◽

Hideyuki Abe ◽

...

Keyword(s):

Renal Cell Carcinoma ◽

Vascular Endothelial Growth Factor ◽

Overall Survival ◽

Cell Death ◽

Growth Factor ◽

Vascular Endothelial ◽

Primary Tumors ◽

Anti Vegf ◽

Programmed Cell Death 1 ◽

Endothelial Growth Factor

Abstract Background Adenosine and its adenosine 2A receptors (A2AR) mediate the immunosuppressive mechanism by which tumors escape immunosurveillance and impede anti-tumor immunity within the tumor microenvironment. However, we do not know whether the adenosine pathway (CD39/CD73/A2AR) plays a role in renal cell carcinoma (RCC). Therefore, we studied the role of immunosuppression in RCC by assessing the adenosine pathway in patients with RCC treated with anti-vascular endothelial growth factor (anti-VEGF) agents or immune checkpoints inhibitors (ICIs) or both. Methods In 60 patients with metastatic RCC, we examined the expression of CD39, CD73, A2AR, and programmed cell death 1 ligand 1 (PD-L1) immunohistochemically in surgically resected tumor tissues and studied the clinicopathological characteristics of these patients. Patients were treated by cytoreductive nephrectomy with systemic therapy with anti-VEGF agent or a combination of the ICIs anti-cytotoxic T-lymphocyte-associated antigen 4 (CTLA4) antibody and programmed cell death 1 (PD-1) antibody. Results Increased expression of A2AR in the primary tumors was associated with metastatic profiles. Patients treated with anti–PD-1 antibody in monotherapy, a combination of anti-PD-1 and anti-CTLA4 antibodies, or anti-VEGF agents showed better response and longer overall survival if the primary tumor had higher PD-L1 expression and lower A2AR expression. In Cox multivariate regression analysis, higher expression of A2AR was associated with shorter overall survival. Conclusions Our findings suggest that the expression of A2AR and PD-L1 in the primary tumors in RCC might predict the outcomes of treatment with anti-VEGF agents and ICIs and that the A2AR pathway might be a molecular target for immunotherapy.

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