X‐rays modulate extracellular matrix in vivo

Giannopoulou, Efstathia; Katsoris, Panagiotis; Hatziapostolou, Maria; Kardamakis, D.; Kotsaki, Elena; Polytarchou, Christos; Parthymou, Anastasia; Papaioannou, Stamatis; Papadimitriou, Evangelia

doi:10.1002/ijc.1535.abs

Cited by 17 publications

(30 citation statements)

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“…Modulation of the extracellular matrix after exposure to ionizing radiation is known. 45 The upregulation of metalloproteinase and collagen observed in the present study indicates that ionizing radiation modulates the synthesis and deposition of extracellular matrix proteins involved in regulating angiogenesis. Little information is available concerning the direct effects of radiation on the extracellular microenvironment, specifically the extracellular matrix and its main component, collagen.…”

Section: Discussionmentioning

confidence: 49%

Radiation‐induced gene expression profile of human cells deficient in 8‐hydroxy‐2′‐deoxyguanine glycosylase

Chaudhry

2005

Intl Journal of Cancer

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The human OGG1 gene encodes a DNA glycosylase that is involved in the base excision repair of 8-hydroxy-2 0 -deoxyguanine (8-OH-dG) from oxidatively damaged DNA. Cellular 8-OH-dG levels accumulate in the absence of this activity and could be deleterious for the cell. To assess the role of 8-oxoguanine glycosylase (OGG1) in the cellular defense mechanism in a specific DNA repair defect background, we set out to determine the expression pattern of base excision repair genes and other cellular genes not involved in the base excision pathway in OGG1-deficient human KG-1 cells after ionizing radiation exposure. KG-1 cells have lost OGG1 activity due to a homozygous mutation of Arg229Gln. Gene expression alterations were monitored at 4, 8, 12 and 24 hr in 2 Gy irradiated cells. Large-scale gene expression profiling was assessed with DNA microarray technology. Gene expression analysis identified a number of ionizing radiation-responsive genes, including several novel genes. There were 2 peaks of radiationinduced gene induction or repression: one at 8 hr and the other at 24 hr. Overall the number of downregulated genes was higher than the number of upregulated genes. The highest number of downregulated genes was at 8 hr postirradiation. Genes corresponding to cellular, physiologic, developmental and extracellular processes were identified. The highest number of radiationinduced genes belonged to the signal transduction category, followed by genes involved in transcription and response to stress. Microarray gene expression data were independently validated by relative quantitative RT-PCR. Surprisingly, none of the genes involved in the base excision repair of radiation-induced DNA damage showed altered expression. ' 2005 Wiley-Liss, Inc.

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Section: Discussionmentioning

confidence: 49%

Radiation‐induced gene expression profile of human cells deficient in 8‐hydroxy‐2′‐deoxyguanine glycosylase

Chaudhry

2005

Intl Journal of Cancer

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“…10 In our study, we found that irradiation of C6 glioma cells, although dose dependently decreased their proliferation in vitro, increased the expression and secretion of metalloproteinases 2 and 9 (MMP-2 and MMP-9, respectively), increased the expression of integrin ␣ v and enhanced their angiogenic activity in vivo, when inoculated onto the chicken embryo CAM and in vitro, in cultures of human endothelial cells.…”

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confidence: 60%

“…[11][12][13] We have previously shown in the in vivo system of the chicken embryo chorioallantoic membrane (CAM) that X-rays enhance angiogenesis induced by C6 glioma cells inoculated onto the tissue immediately after irradiation of the CAM. 10 In our study, we found that irradiation of C6 glioma cells, although dose dependently decreased their proliferation in vitro, increased the expression and secretion of metalloproteinases 2 and 9 (MMP-2 and MMP-9, respectively), increased the expression of integrin ␣ v and enhanced their angiogenic activity in vivo, when inoculated onto the chicken embryo CAM and in vitro, in cultures of human endothelial cells.…”

mentioning

confidence: 60%

“…10 Human umbilical vein endothelial cells (HUVEC) were isolated from human umbilical cords and cultured as previously described. 14 HUVEC were grown as monolayers in medium M199 that was supplemented with 15% FBS, 150 g/ml endothelial cell growth supplement, 5 U/ml heparin sodium, 100 U/ml penicillin-streptomycin and 50 g/ml gentamycin and used at passages 1-3.…”

Section: Cell Culturementioning

confidence: 99%

“…10 In brief, C6 glioma cells were plated in 24-well plates at a density of 2.0 ϫ 10 4 cells per well, in Ham's F12 supplemented with 10% FBS and antibiotics. Twenty-four hours later, cells were irradiated at 2.5, 5, 10, 20 and 40 Gy.…”

Section: Zymographymentioning

confidence: 99%

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Irradiated C6 glioma cells induce angiogenesis in vivo and activate endothelial cells in vitro

Parthymou

Kardamakis

Pavlopoulos

et al. 2004

Intl Journal of Cancer

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Malignant gliomas are angiogenesis dependent and present a remarkable degree of resistance to radiotherapy. In the present work, we studied the effect of irradiation of C6 glioma cells on their proliferation and activation in vitro and on glioma cell-induced angiogenesis in vivo and in vitro. Irradiation of C6 glioma cells decreased cell proliferation in a dosedependent manner. Interestingly, metalloproteinase-2 and -9 expression and secretion, as well as integrin ␣ v expression, increased with elevated doses of X rays 48 hr after irradiation and was mostly evident at the higher doses used. When pre-irradiated C6 cells were implanted on nonirradiated chicken embryo chorioallantoic membranes (CAMs), there was a significant dose-dependent increase in tumor induced angiogenesis, compared to angiogenesis induced by nonirradiated cells. Similar results were obtained when C6 cells were irradiated 48 hr after their inocculation onto nonirradiated CAMs. In the same line, conditioned medium from irradiated C6 cells significantly increased endothelial cell proliferation and migration in vitro, in a manner dependent on the dose of X rays. These results explain at least in part the low effectiveness of radiation therapy of malignant gliomas and support the notion that inhibition of angiogenesis in parallel with radiotherapy may represent a new therapeutic approach. © 2004 Wiley-Liss, Inc. Key words: angiogenesis; endothelial cells; glioma cells; metalloproteinase-2; migration; proliferation; X raysMalignant gliomas, the most common type of brain tumors in adults, present a remarkable degree of neovascularisation and invasiveness into surrounding tissues. 1 These features account for their poor prognosis, and although combinations of surgery, radiotherapy and chemotherapy are used, more than 90% of the patients experience local recurrence and their survival is extremely low. These facts stress the need for more effective therapeutic strategies. 2 Rapid cell proliferation and high invasive capacity of glioma cells are crucial for tumor development and progression. Moreover, induction of angiogenesis is an essential prerequisite for tumor growth and spread, and precedes malignant tumor formation. 3 Angiogenesis is a fundamental process by which new blood vessels are formed from pre-existing ones. It is a very important step in reproduction, development and wound healing. Furthermore, angiogenesis is very important in several pathological mechanisms like carcinogenesis, tumor metastasis and inflammation. 4 Radiation is considered to inhibit angiogenesis through damage to the endothelium. 5,6 However, in vivo studies suggest that ionizing radiation induces vascular endothelial growth factor (VEGF) production 7 and enhances both the formation of new blood vessels 8 -11 and the secondary development of tumors. 11-13 We have previously shown in the in vivo system of the chicken embryo chorioallantoic membrane (CAM) that X-rays enhance angiogenesis induced by C6 glioma cells inoculated onto the tissue immediately after irradiation...

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Serum levels of angiogenic cytokines decrease after radiotherapy in non-Hodgkin lymphomas

et al. 2008

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X‐rays modulate extracellular matrix in vivo

Cited by 17 publications

References 0 publications

Radiation‐induced gene expression profile of human cells deficient in 8‐hydroxy‐2′‐deoxyguanine glycosylase

Radiation‐induced gene expression profile of human cells deficient in 8‐hydroxy‐2′‐deoxyguanine glycosylase

Irradiated C6 glioma cells induce angiogenesis in vivo and activate endothelial cells in vitro

Serum levels of angiogenic cytokines decrease after radiotherapy in non-Hodgkin lymphomas

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