scholarly journals 18F-fluorodeoxyglucose positron emission tomography/computed tomography and the relationship between fluorodeoxyglucose uptake and the expression of hypoxia-inducible factor-1 , glucose transporter-1 and vascular endothelial growth factor in thymic epithelial tumours

2013 ◽  
Vol 44 (2) ◽  
pp. e105-e112 ◽  
Author(s):  
H. Toba ◽  
K. Kondo ◽  
Y. Sadohara ◽  
H. Otsuka ◽  
M. Morimoto ◽  
...  
Blood ◽  
1997 ◽  
Vol 89 (2) ◽  
pp. 503-509 ◽  
Author(s):  
Jonathan M. Gleadle ◽  
Peter J. Ratcliffe

Abstract The induction by hypoxia of genes such as erythropoietin, vascular endothelial growth factor (VEGF ), and glucose transporter-1 (Glut-1) is mediated in part by a transcriptional complex termed hypoxia-inducible factor-1 (HIF-1). Several lines of evidence have implicated protein phosphorylation in the mechanism of activation of HIF-1 by hypoxia. Recent reports have described the activation of the tyrosine kinase src by severe hypoxia, and a role in the induction of VEGF by severe hypoxia has been proposed. This led us to examine whether src and related kinases operated more widely in the hypoxic induction of HIF-1 and HIF-1–dependent genes regulated by hypoxia. Measurements of src kinase activity in cells exposed to varying severities of hypoxia showed activation by severe hypoxia (0.1% oxygen or catalyst induced anoxia), but not 1% oxygen. This contrasted with the marked induction of HIF-1 by exposure to 1% oxygen. Manipulations of src activity were produced by transient and stable transfection of Hep3B cells. Despite substantial changes in src activity, no alteration was seen in the normoxic or hypoxic expression of erythropoietin, VEGF, or Glut-1, or in the regulation of HIF-1–dependent reporter genes inducible by hypoxia. Similarly, we found that the expression of these genes in src- or c-src kinase-deficient cells did not differ from wild-type cells at either 1% oxygen or more severe hypoxia. These results indicate that src is not critical for the hypoxic induction of HIF-1, erythropoietin, VEGF, or Glut-1.


Pharmacology ◽  
2021 ◽  
pp. 1-11
Author(s):  
Man-Ping Huang ◽  
Shan-Zhi Gu ◽  
Bin Huang ◽  
Guo-Wen Li ◽  
Zheng-Ping Xiong ◽  
...  

<b><i>Introduction:</i></b> Intrahepatic cholangiocarcinoma (ICC), which is difficult to diagnose and is usually fatal due to its late clinical presentation and a lack of effective treatment, has risen over the past decades but without much improvement in prognosis. <b><i>Objective:</i></b> The study aimed to investigate the role of apatinib that targets vascular endothelial growth factor receptor-2 (VEGFR2) in ICC. <b><i>Methods:</i></b> MTT assays, cell scratch assays, and tube formation assays were used to assess the effect of apatinib on human ICC cell line (HuCCT-1) and RBE cells proliferation, migration, and angiogenic capacity, respectively. Expression of vascular endothelial growth factor (VEGF), VEGFR2, signal transducer and activator of transcription factor 3 (STAT3), pSTAT3, and hypoxia inducible factor 1 subunit alpha (HIF-1α) pathway proteins was assessed using Western blotting and mRNA expression analysis in HuCCT-1 was performed using RT-qPCR assays. The pcDNA 3.1(-)-VEGFR2 and pcDNA 3.1(-)-HIF-1α were transfected into HuCCT-1 and RBE cells using Lipofectamine 2,000 to obtain overexpressed HuCCT-1 and RBE cells. <b><i>Results:</i></b> We found that apatinib-inhibited proliferation, migration, and angiogenesis of HuCCT-1 and RBE cells in vitro in a dose-dependent manner. We also proved that apatinib effectively inhibits angiogenesis in tumor cells by blocking the expression of VEGF and VEGFR2 in these cells. In addition, we demonstrated that apatinib regulates the expression of STAT3 phosphorylation by inhibiting VEGFR2. Finally, we showed that apatinib regulates ICC angiogenesis and HIF-1α/VEGF expression via STAT3. <b><i>Conclusions:</i></b> Based on the above findings, we conclude that apatinib inhibits HuCCT-1 and RBE cell proliferation, migration, and tumor angiogenesis by inhibiting the VEGFR2/STAT3/HIF-1α axis signaling pathway. Apatinib can be a promising drug for ICC-targeted molecular therapy.


Blood ◽  
2000 ◽  
Vol 95 (1) ◽  
pp. 189-197 ◽  
Author(s):  
Hideo Kimura ◽  
Alessandro Weisz ◽  
Yukiko Kurashima ◽  
Kouichi Hashimoto ◽  
Tsutomu Ogura ◽  
...  

Abstract Nitric oxide (NO) regulates production of vascular endothelial growth factor (VEGF) by normal and transformed cells. We demonstrate that NO donors may up-regulate the activity of the human VEGF promoter in normoxic human glioblastoma and hepatoma cells independent of a cyclic guanosine monophosphate–mediated pathway. Deletion and mutation analysis of the VEGF promoter indicates that the NO-responsive cis-elements are the hypoxia-inducible factor-1 (HIF-1) binding site and an adjacent ancillary sequence that is located immediately downstream within the hypoxia-response element (HRE). This work demonstrates that the HRE of this promoter is the primary target of NO. In addition, VEGF gene regulation by NO, as well as by hypoxia, is potentiated by the AP-1 element of the gene. Our study also reveals that NO and hypoxia induce an increase in HIF-1 binding activity and HIF-1 protein levels, both in the nucleus and the whole cell. These results suggest that there are common features of the NO and hypoxic pathways of VEGF induction, while in part, NO mediates gene transcription by a mechanism distinct from hypoxia. This is demonstrated by a difference in sensitivity to guanylate cyclase inhibitors and a different pattern of HIF-1 binding. These results show that there is a primary role for NO in the control of VEGF synthesis and in cell adaptations to hypoxia. (Blood. 2000;95:189-197)


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