Tesi: "Vascular endothelial growth factor-receptor 2"

1

Ruch, Claudia. "Structure / function analysis of the extracellular domain of vascular endothelial growth factor receptor-2 (VEGFR-2) /". Zürich : ETH/PSI, 2007. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=17030.

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2

Jellbauer, Stefan. "Tumorvakzinierung gegen den "Vascular Endothelial Growth Factor Receptor 2" (VEGFR2)mittels heterologem Antigentransport durch rekombinante Salmonellen". Diss., lmu, 2010. http://nbn-resolving.de/urn:nbn:de:bvb:19-120905.

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3

Iizuka, Takumi. "Vascular endothelial growth factor receptor 3 (VEGFR3) expression in the mouse uterus during decidualization /". Available to subscribers only, 2008. http://proquest.umi.com/pqdweb?did=1650512501&sid=1&Fmt=2&clientId=1509&RQT=309&VName=PQD.

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4

Higgins, Kelly Jean. "Regulation of vascular endothelial growth factor receptor-2 in pancreatic and breast cancer cells by Sp proteins". Texas A&M University, 2003. http://hdl.handle.net/1969.1/6010.

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Vascular endothelial growth factor receptor-2 (VEGFR2) is a key angiogenic factor, and angiogenesis is an important physiological process associated with neovascularization, growth, and metastasis of many different tumors. The mechanism of VEGFR2 gene expression was investigated in MiaPaCa-2, Panc-1, and AsPC-1 pancreatic cancer cells transfected with a series of VEGFR2 promoter deletion/mutated constructs, and the results indicated that the GC-rich Ã¢ÂÂ60 to Ã¢ÂÂ37 region of the promoter was essential for VEGFR2 expression in these cell lines. EMSA and ChIP assays showed that Sp proteins are expressed and bind to the proximal GC-rich region of the VEGFR2 promoter. RNA interference studies on Sp proteins demonstrated that Sp1, Sp3, and Sp4 all contributed to VEGFR2 gene/protein expression in pancreatic cancer cells. VEGFR2 gene expression was also investigated in ZR-75 and MCF-7 breast cancer cells. ZR-75 cells treated with 10 nM 17b-estradiol (E2) increased VEGFR2 mRNA levels/protein expression. The VEGFR2 promoter was induced by E2 in ZR-75 cells, and analysis of the VEGFR2 promoter identified the GC rich -60 to -37 region that was required for E2-mediated transactivation. EMSA and ChIP assays confirmed that Sp1, Sp3, and Sp4 proteins are expressed in ZR-75 cells and bind the proximal GC-rich region of the VEGFR2 promoter. RNA interference was used to determine the relative contributions of Sp proteins on hormonal regulation of VEGFR2 through ER/Sp complexes, and interestingly, in ZR-75 cells, hormone-induced activation of VEGFR2 involves ERa/Sp3 and ERa/Sp4 but not ERa/Sp1. In MCF-7 cells treated with 10 nM E2, VEGFR2 mRNA levels were decreased. Analysis of the VEGFR2 promoter revealed that the same GC-rich region important for E2-mediated upregulation in ZR-75 cells was responsible for E2-dependent downregulation of VEGFR2 gene expression in MCF-7 cells. EMSA and ChIP assays confirmed that Sp1, Sp3, and Sp4 proteins are expressed in MCF-7 cells and bind to the proximal GC-rich region of the VEGFR2 promoter. RNA interference studies showed that Sp1, Sp3, and Sp4 are involved in the E2-mediated downregulation of VEGFR2 in MCF-7 cells, and ERa/Sp protein-promoter interactions are accompanied by recruitment of the corepressor SMRT using the ChIP assay.

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5

Deshpande, Abhishek. "Vascular Endothelial Growth Factor Receptor-2 (VEGFR-2) and blood vessel density changes in an experimental model of Chronic Hydrocephalus". Kent State University / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=kent1279288736.

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6

Kwan, Joanne. "Induction of tumor proliferation and metastasis by expression of vascular endothelial growth factor receptor 2 in prostate carcinomas". Thesis, Boston University, 2012. https://hdl.handle.net/2144/12462.

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Thesis (M.A.)--Boston University PLEASE NOTE: Boston University Libraries did not receive an Authorization To Manage form for this thesis or dissertation. It is therefore not openly accessible, though it may be available by request. If you are the author or principal advisor of this work and would like to request open access for it, please contact us at open-help@bu.edu. Thank you.
Vascular endothelial growth factor receptor 2 (VEGFR2) was first discovered on the cells of blood vessels, and has thus been referred to as an endothelial receptor. However, recent evidence suggests that some tumor cells may express VEGFR2 as well. We examine the function of the lowly metastatic human prostate cancer cell line PC3M and its highly metastatic lymph node variant PC3M-LN4. We discovered that PC3M-LN4 cells express high levels of VEGFR2. In vivo, PC3M-LN4 tumors are larger, more metastatic, and more vascularized than PC3M tumors. To further demonstrate the function of VEGFR2, PC3M cells were transfected with a VEGFR2 plasmid and G418 resistant cells were selected then grown as clones. PC3M-VEGFR2 cells were analyzed by Western blot analysis, a migration assay, and a proliferation assay. Cells expressing high levels of VEGFR2 were selected through Western blotting. A Transwell migration assay examining PC3M-VEGFR2.28 revealed greater cell migration towards VEGF-treated media as compared to VEGF-untreated media. A proliferation assay for this same clone showed greater cell proliferation with increasing concentrations of VEGF in both SF and 1% FBS media. These data suggest a direct relationship between VEGFR2 expression and tumor proliferation and metastasis. Furthermore, we noticed that an elongated cell morphology may be a characteristic of metastatic cells. Immunohistochemical analysis of prostate cancer patient biopsies reveals VEGFR2 expression on both tumor cells and endothelial cells. Interestingly, we noticed that this expression is heterogeneous between different patients and even varies within the same biopsy. Our data suggests that anti-VEGFR2 therapies may target both the tumor and blood vessels to inhibit prostate cancer disease progression in those patients that express the receptor.

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王, 英泰. "Hypoxia and vascular endothelial growth factor selectively upregulate angiopoietin-2 in bovine microvascular endothelial cells". Kyoto University, 2001. http://hdl.handle.net/2433/150200.

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8

Magnusson, Peetra. "Fibroblast Growth Factor Receptor-1 Function in Vasculo- and Angiogenesis". Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis : Univ.-bibl. [distributör], 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-5824.

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9

Cheluvappa, Rajkumar. "Pathophysiology of Liver Sinusoidal Endothelial Cells". Thesis, The University of Sydney, 2008. http://hdl.handle.net/2123/2802.

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Owing to its strategic position in the liver sinusoid, pathologic and morphologic alterations of the Liver Sinusoidal Endothelial Cell (LSEC) have far-reaching repercussions for the whole liver and systemic metabolism. LSECs are perforated with fenestrations, which are pores that facilitate the transfer of lipoproteins and macromolecules between blood and hepatocytes. Loss of LSEC porosity is termed defenestration, which can result from loss of fenestrations and/ or decreases in fenestration diameter. Gram negative bacterial endotoxin (Lipopolysaccharide, LPS) has marked effects on LSEC morphology, including induction LSEC defenestration. Sepsis is associated with hyperlipidemia, and proposed mechanisms include inhibition of tissue lipoprotein lipase and increased triglyceride production by the liver. The LSEC has an increasingly recognized role in hyperlipidemia. Conditions associated with reduced numbers of fenestrations such as ageing and bacterial infections are associated with impaired lipoprotein and chylomicron remnant uptake by the liver and consequent hyperlipidemia. Given the role of the LSEC in liver allograft rejection and hyperlipidemia, changes in the LSEC induced by LPS may have significant clinical implications. In this thesis, the following major hypotheses are explored: 1. The Pseudomonas aeruginosa toxin pyocyanin induces defenestration of the LSEC both in vitro and in vivo 2. The effects of pyocyanin on the LSEC are mediated by oxidative stress 3. Defenestration induced by old age and poloxamer 407 causes intrahepatocytic hypoxia and upregulation of hypoxia-related responses 4. Defenestration of the LSEC seen in old age can be exacerbated by diabetes mellitus and prevented or ameliorated by caloric restriction commencing early in life

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10

Cheluvappa, Rajkumar. "Pathophysiology of Liver Sinusoidal Endothelial Cells". University of Sydney, 2008. http://hdl.handle.net/2123/2802.

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Doctor of Philosophy(PhD)
Owing to its strategic position in the liver sinusoid, pathologic and morphologic alterations of the Liver Sinusoidal Endothelial Cell (LSEC) have far-reaching repercussions for the whole liver and systemic metabolism. LSECs are perforated with fenestrations, which are pores that facilitate the transfer of lipoproteins and macromolecules between blood and hepatocytes. Loss of LSEC porosity is termed defenestration, which can result from loss of fenestrations and/ or decreases in fenestration diameter. Gram negative bacterial endotoxin (Lipopolysaccharide, LPS) has marked effects on LSEC morphology, including induction LSEC defenestration. Sepsis is associated with hyperlipidemia, and proposed mechanisms include inhibition of tissue lipoprotein lipase and increased triglyceride production by the liver. The LSEC has an increasingly recognized role in hyperlipidemia. Conditions associated with reduced numbers of fenestrations such as ageing and bacterial infections are associated with impaired lipoprotein and chylomicron remnant uptake by the liver and consequent hyperlipidemia. Given the role of the LSEC in liver allograft rejection and hyperlipidemia, changes in the LSEC induced by LPS may have significant clinical implications. In this thesis, the following major hypotheses are explored: 1. The Pseudomonas aeruginosa toxin pyocyanin induces defenestration of the LSEC both in vitro and in vivo 2. The effects of pyocyanin on the LSEC are mediated by oxidative stress 3. Defenestration induced by old age and poloxamer 407 causes intrahepatocytic hypoxia and upregulation of hypoxia-related responses 4. Defenestration of the LSEC seen in old age can be exacerbated by diabetes mellitus and prevented or ameliorated by caloric restriction commencing early in life

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11

Ward, Stephen. "Small Interfering RNA Decreases VEGF mRNA Expression and Proliferation of Colorectal Cancer Cells". Yale University, 2006. http://ymtdl.med.yale.edu/theses/available/etd-06282006-151558/.

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Vascular endothelial growth factor (VEGF-A) was first described in 1989 for its angiogenic and mitogenic properties. Early studies indicated that VEGF-A acts primarily in a paracrine pathway which is limited to vascular endothelium. Further investigation showed that VEGF-A and VEGF receptor-2 (VEGFR-2) are expressed by many solid tumors and improve cell growth and survival. Therefore, VEGF-A may act via an autocrine pathway that effects tumor cellular proliferation by binding VEGFR-2 at the cell surface. This study utilizes small interfering RNA (siRNA) technology to investigate the presence of an autocrine loop in human RKO colorectal cancer cells. RT-PCR demonstrated the expression of VEGF-A, VEGF-B, VEGF-D, placental growth factor (PlGF), VEGFR-2, neuropilin-1 (NP-1) and neuropilin-2 (NP-2) in vitro by RKO cells. Transfection with siRNA against VEGF-A resulted in a 94% knockdown of VEGF-A expression by ELISA. Northern blot, quantitative real time PCR and semiquantitative RT-PCR confirmed the knockdown data. In addition, transfected RKO cells showed a 67% decrease in cellular proliferation by WST-1 assay. This data correlated to the ELISA results. In summary, the presence of VEGF-A and VEGFR-2 argues in favor of an autocrine loop in human colorectal cancer cells. siRNA targeting of VEGF-A remains a promising anti-tumor therapeutic strategy.

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12

Shao, Esther Szu-Chia. "Study of the role of activin receptor like kinase-1 signaling in control of vascular endothelial growth factor expression and atherosclerosis". Diss., Restricted to subscribing institutions, 2009. http://proquest.umi.com/pqdweb?did=2026896091&sid=1&Fmt=2&clientId=1564&RQT=309&VName=PQD.

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13

Las, Heras Alonso Hortensia Paula. "Implicaciones de la sobreexpresión de la ciclooxigenasa-2 (COX-2) en la carcinogénesis colónica experimental". Doctoral thesis, Universitat de Lleida, 2011. http://hdl.handle.net/10803/52097.

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INTRODUCCIÓ L’angiogènesi és essencial per al creixement dels tumors sòlids i participa en el procés metastàtic. El VEGF-C, un potent factor angiogènic, es troba elevat en pacients amb càncer colorectal (CCR). Hi ha evidències que suggereixen que la COX-2 és un factor important en el procés de carcinogènesi colorectal. L’objectiu principal de l’estudi és investigar l’efecte que un inhibidor selectiu de la ciclooxigenasa-2, pugui tenir a un model de carcinogènesi colònica experimental sobre la superfície tumoral del còlon, i la seva traducció als nivells sèrics de VEGF-C i a l’expressió de ciclooxigenasa-2 (COX-2). MATERIAL I MÈTODES Es van utilitzar 100 rates Sprague-Dawley no consanguínies distribuïdes en cinc grups: grup control, grup amb CCR induït amb DMH, grup de rates tractades amb celecoxib, grup de rates tractades amb àcid acetilsalicílic i grup de rates tractades amb indometacina. Després del sacrifici, es van prendre mostres de sang per determinar el VEGF-C sèric mitjançant ELISA i mostres dels segments del còlon i d’aquells suggestius de contenir neoplàsia per a estudiar l’expressió de COX-2 als tumors i a la mucosa normal del còlon descendent mitjançant immunohistoquímica. Es va utilitzar la prova estadística més idònia a cada supòsit d’estudi i es va considerar significatiu quan la p£0,05. RESULTATS Vam trobar expressió positiva de COX-2 en el 57,14-66,67% dels tumors de còlon. El 72% de tumors carcinomes mucinosos van presentar un score de tinció de COX-2 positiu, vs. un 48,46% dels adenocarcinomes (p<0,05). Es van trobar diferències significatives entre els grups que van rebre fàrmacs quan es va comparar el nivell sèric de VEGF-C (p=0,008). El grup que va prendre àcid acetilsalicílic presentà uns nivells sèrics menors als del grup que va rebre celecoxib (63,67 vs. 92,58 pg/ml) (p=0,003). No es van apreciar diferències significatives entre el grup que va rebre celecoxib i el grup control amb inducció tumoral (92,58 vs. 89,89 pg/ml; p=0,698). No es van trobar diferències estadísticament significatives entre els valors de VEGF-C sèric i l’expressió tumoral de COX-2 a cap dels grups d’estudi (p>0,05). Es van trobar diferències significatives entre el valor sèric mig de VEGF-C i l’extensió de l’expressió de COX-2 en el tumor (p=0,035). També es va trobar correlació estadísticament significativa entre el VEGF-C sèric i la suma de superfície tumoral (p=0,045). Es van trobar diferències estadísticament significatives en el VEGF-C sèric segons els animals presentessin o no metàstasis a distància o hematògenes (p=0,015). CONCLUSIONS La major part de tumors de còlon van expressar COX-2. L’expressió de COX-2 es va associar al tipus de tumor, i s’incrementa d’acord amb l’augment de la malignitat de la histologia del tumor. El VEGF-C sèric es relaciona amb la progressió de la malaltia. Valors elevats es van correlacionar amb superfícies tumorals altes de manera estadísticament significativa. Celecoxib no va reduir de manera significativa l’expressió de COX-2 als tumors respecte dels grups tractats amb fàrmacs no selectius, ni va disminuir de manera significativa els valors sèrics de VEGF-C, ni la suma de superfície tumoral en el còlon. L’àcid acetilsalicílic indueix una disminució en els nivells sèrics de VEGF-C, propers als nivells control, però no van existir canvis en l’expressió tumoral de COX-2, ni en la suma de superfície tumoral en comparar aquest grup amb els altres.
INTRODUCCIÓN La angiogénesis es esencial para el crecimiento de los tumores sólidos y participa en el proceso metastático. El VEGF-C, un potente factor angiogénico, se encuentra elevado en pacientes con cáncer colorrectal (CCR).Hay muchas evidencias que sugieren que la COX-2 es un factor importante en el proceso de carcinogénesis colorrectal. El objetivo principal del estudio es investigar el efecto que un inhibidor selectivo de la ciclooxigenasa-2, comparándolo con otros no selectivos, pueda tener, en un modelo de carcinógesis colónica experimental, sobre la superficie tumoral del colon y su traducción en los niveles séricos de VEGF-C y en la expresión de ciclooxigenasa-2 (COX-2). MATERIAL Y MÉTODOS Se utilizaron 100 ratas Sprague-Dawley no consanguíneas distribuidas en cinco grupos: grupo control, grupo con CCR inducido con DMH, grupo de ratas tratadas con celecoxib, grupo de ratas tratadas con ácido acetilsalicílico y grupo de ratas tratadas con indometacina. Tras el sacrificio, se tomaron muestras de sangre para determinar el VEGF-C sérico mediante ELISA y muestras de los segmentos del colon y de aquellos sugestivos de contener neoplasia para estudiar la expresión de COX-2 en los tumores y en la mucosa normal del colon descendente mediante inmunohistoquímica. Se utilizó la prueba estadística más idónea en cada supuesto de estudio y se consideró significativo cuando la p£ 0,05. RESULTADOS Encontramos expresión positiva de COX-2 en el 57,14 - 66,67% de los tumores de colon. El 72% de tumores carcinomas mucinosos presentaron un score de tinción de COX-2 positivo, vs. un 48,46% de los adenocarcinomas (p<0,05). Se encontraron diferencias significativas entre los grupos que recibieron fármacos cuando se comparó el valor sérico de VEGF-C (p=0,008). El grupo que tomó ácido acetilsalicílico presentó unos niveles séricos menores a los del grupo que recibió celecoxib (63,67 vs. 92,58 pg/ml) (p=0,003). No se apreciaron diferencias significativas entre el grupo que recibió celecoxib y el grupo control con inducción tumoral (92,58 vs. 89,89 pg/ml.) (p=0,698). No se encontraron diferencias estadísticamente significativas entre los valores de VEGF-C sérico y la expresión tumoral de COX-2 en ninguno de los grupos de estudio (p>0,05). Se encontraron diferencias significativas entre el valor sérico medio de VEGF-C y la extensión de la expresión de COX-2 en el tumor (p=0,035). También se halló correlación estadísticamente significativa entre el valor circulante de VEGF-C sérico y la suma de superficie tumoral (p=0,045). Se encontraron diferencias estadísticamente significativas en el valor sérico de VEGF-C según los animales presentasen o no metástasis a distancia o hematógenas (p=0,015). CONCLUSIONES La mayoría de tumores de colon inducidos experimentalmente en la rata expresaron COX-2. La expresión de COX-2 en el CCR se asocia de forma significativa al tipo de tumor, incrementándose conforme aumentaba la malignidad de la histología del tumor. El VEGF-C sérico se relaciona con la progresión de la enfermedad. Valores elevados se correlacionaron con sumas de superficies tumorales elevadas de un modo estadísticamente significativo. Celecoxib no redujo de un modo significativo la expresión de COX-2 en los tumores respecto de los grupos tratados con fármacos no selectivos, ni disminuyó de forma significativa los valores séricos de VEGF-C, ni la suma de superficie tumoral en el colon. El ácido acetilsalicílico induce una disminución en los niveles séricos circulantes de VEGF-C cercanos a los niveles control. Sin embargo, no existieron cambios en la expresión de COX-2 en los tumores, ni en la suma de superficie tumoral al comparar este grupo con los demás.
INTRODUCTION Angiogenesis is essential for the growth of solid tumours and takes part in the metastatic process. VEGF-C, a strong angiogenic factor, is increased in patients with colorectal cancer (CRC). There are evidences suggesting that COX-2 is an important factor in the colorectal carcinogenesis process. The main aim of the study is to investigate the effect that a selective COX-2 inhibitor, comparing it with non-selective ones, could have on experimental colon carcinogenesis, on the colorectal tumour area, and its results in the serum VEGF-C levels and in the cyclooxigenase-2 (COX-2) expression. MATERIAL AND METHODS 100 Sprague-Dawley rats without consanguinity were used. They were divided into five groups: control group, group with DMH induced CRC, group that was treated with celecoxib, group that was treated with aspirin and group that was treated with indomethacin. Blood samples were taken after slaughter of rats, in order to determine serum VEGF-C with ELISA technique. Colon segments samples and specimens from the areas that were suggested to contain neoplasms were taken too, in order to study COX-2 expression in colon tumors and in the normal mucosa with immunohistochemistry technique. The most appropriate statistical test was used in each case of the study and it was considered significant when p£ 0.05. RESULTS We found positive COX-2 expression in 57.14-66.67% of colon tumours. 72% of mucinous carcinomas presented a positive score for COX-2 expression, vs. 48.46% of adenocarcinomas (p<0.05). We found significant differences between groups that received drugs when we compared the serum VEGF-C level (p=0.008). The AAS group presented lower serum VEGF-C levels than the celecoxib group (63.67 vs. 92.58 pg/ml) (p=0.003). We didn’t appreciate significant differences between the celecoxib group and the control group with tumor induction (92.58 vs. 89.89 pg/ml) (p=0.698). There were no statistically significant differences between the serum VEGF-C levels and tumor expression of COX-2 in any of the groups of the study (p>0.05). We found significant differences between the serum VEGF-C level and the extension of COX-2 expression in the tumor (p=0.035). We also found statistically significant correlation between the value of serum VEGF-C and the sum of tumor area (p = 0.045). Statistically significant differences were found in the serum VEGF-C level between animals having or not hematogenous metastasis (p=0.015). CONCLUSIONS Most experimentally induced colon tumors in rats expressed COX-2. The expression of COX-2 in CRC is significantly associated with the type of tumor, and increases according to the increases of malignancy of the tumor histology. Serum VEGF-C is related to disease progression. High values were correlated with high sum of tumor surfaces in a statistically significant manner. Celecoxib didn’t reduce significantly the expression of COX-2 in tumors regarding groups treated with non-selective drugs, nor significantly decreased serum VEGF-C, or the sum of tumor area in the colon. Aspirin decreases serum VEGF-C levels which were similar to control levels. However, there were no changes in the expression of COX-2 in tumors, or the sum of tumor area by comparing this group with other treated groups.

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14

Sköld, Mattias. "On VEGF and related factors in neurotrauma /". Stockholm, 2004. http://diss.kib.ki.se/2004/91-7349-986-2/.

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15

Ferraro, Bernadette. "Intradermal Delivery of Plasmids Encoding Angiogenic Growth Factors by Electroporation Promotes Wound Healing and Neovascularization". [Tampa, Fla] : University of South Florida, 2009. http://purl.fcla.edu/usf/dc/et/SFE0002823.

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16

Sarkar, Nondita. "Myocardial angiogenesis induced by plasmid VEGF-A165 gene transfer : experimental and clinical studies /". Stockholm, 2005. http://diss.kib.ki.se/2005/91-7140-196-2/.

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17

Star, Gregory. "The effects of bone morphogenic proteins and transforming growth factor [beta] on in-vitro endothelin-1 production by human pulmonary microvascular endothelial cells /". Thesis, McGill University, 2008. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=111942.

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Introduction: Idiopathic Pulmonary arteriole hypertension (IPAH) is a rare but severely debilitating disease that strikes women to men at a ratio of 3:1. Endothelial cell (EC) dysfunction is a hallmark of the disease. This includes rapid growth of the ECs until the occlusion of the vasculature as well as decreased blood levels of vasodilators. Markedly increased levels of endothelin-1, a potent vasoconstrictor and smooth muscle mitogen, have been noted in IPAH patients.
Recently mutations in the bone morphogenic protein receptor type II (BMPRII) have been linked to the disease. Interestingly mutations in activin-like kinase-1 (ALK-1) and endoglin have been linked to hereditary haemorrhagic telangiectasia (HHT), a disease that results in PAH clinically indistinguishable from IPAH. All of these proteins are either receptors or co-receptors to members of the TGFbeta superfamily. The connection of these mutations to the disease still remains largely a mystery to researchers and the effects of either bone morphogenic proteins 2, 4, 7 or TGFbeta levels on endothelin-1(ET-1) production in human microvascular endothelial cells cultured from normal lungs (HMVEC-LBI) are unknown.
Methods: HMVEC-LBI cells were cultured in the presence of various concentrations of BMP 2,4,7 and TGFbeta, in complete media or serum starved conditions. After allotted time points the media was collected and assayed by ELISA, meanwhile the cells were lysed and protein content assayed for normalization purposes. Small Mothers against Decapentaplegic (SMAD) 1/5 phosphorylation was also measured.
Results and Conclusions: Despite evidence that all BMPs used were biologically active, namely through SMAD phosphorylation studies, only BMP7 at very high dosages increased ET-1 production levels. TGFbeta had a more pronounced effect at earlier time points with lower concentrations. The results provide insights on the effects of an important group of proteins, the BMPs and TGFbeta, on lung microvascular ECs and which are likely the key cellular player In IPAH development. These findings may have clinical relevance in terms of control of the disease and understanding the normal response of these cells BMPs and TGFbeta.

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Dreilich, Martin. "Predictive Factors in Esophageal Carcinoma". Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis : Univ.-bibl. [distributör], 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-6831.

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19

Rennel, Emma. "Molecular Mechanisms in Endothelial Cell Differentiation". Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis : Univ.-bibl. [distributör], 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-4059.

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20

Gomes, Luana Pimenta. "Avaliação dos fatores de crescimento endotelial vascular VEGF e de seus principais receptores VEGFR-1 e -2 no processo de cicatrização com influência da radioterapia em ratos da linhagem Wistar". Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/5/5160/tde-05112013-125011/.

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Danos teciduais de qualquer natureza desencadeiam uma série de eventos que irão promover a regeneração ou a cicatrização do tecido lesado. Este reparo é um processo complexo que envolve a interação de diversos tipos celulares que são ativados por uma vasta gama de mediadores químicos, componentes da matriz extracelular, microorganismos e alterações físico químicas no microambiente da lesão e das áreas adjacentes. A participação do fator de crescimento endotelial vascular (VEGF) e de seus dois principais receptores (VEGFR-1 e -2) é de grande importância nos processos de cicatrização levando-se em conta a neovascularização. Após uma análise circunstanciada da literatura sobre os efeitos da radioterapia na neovascularização e a relação com a expressão do VEGF e VEGFR-1 e -2 na cicatrização observou-se que ainda há uma série de questões a serem investigadas. O objetivo desse projeto de pesquisa é estudar a expressão imuno-histoquímica do VEGF e VEGFR-1 e -2 e a densidade vascular sanguínea (DVS) após incisão e reparação cutânea em animais sob influência da radioterapia e em um período de aproximadamente seis meses. Neste estudo foram utilizados 60 ratos da linhagem Wistar distribuídos aleatoriamente em seis grupos (controle 3 e 6 meses, radioterapia pré-cirúrgica 3 e 6 meses, radioterapia pós-cirúrgica 3 e 6 meses). Após a eutanásia dos animais de acordo com os princípios bioéticos, foram retirados os espécimes alvo que foram avaliados macro e microscopicamente. O estudo imuno-histoquímico dos VEGFs foram realizados usando os anticorpos específicos supracitados nas diluições especificadas pelo fabricante, enquanto o estudo do DVS foi realizado com o anticorpo Von Willebrand Factor (VWF) que foi utilizado para marcar especificamente as células endoteliais. Nos períodos de tempo estudados, evidenciou-se a expressão significativa destes fatores de crescimento no tecido, na maioria dos casos. Os casos primeiramente irradiados apresentaram celularidade bizarra, com células gigantes e multinucleadas, estruturas do estroma hialinizadas e necrose imunomarcadas de moderada a forte para receptores de VEGF no endotélio e vasos sanguíneos. Essas características são consistentes com a literatura, uma vez que a forte relação do VEGFR-2 e a sua persistência na neovascularização e formação de tecido de granulação foram evidenciados. Os resultados mostraram que a expressão de VEGF é constantemente expressa em diferentes tempos da cicatrização de feridas e formação de cicatriz
Tissue damages of any nature unchain a series of events that will promote regeneration or healing of the injured tissue. This repair is a complex process that involves the interaction of various cells types. These cells are activated by a vast gamma of chemical mediators of the extracellular matrix, microorganisms and chemical and physical alterations in the injury microenvironment and adjacent areas. The participation of vascular endothelial growth factors (VEGF) and their two main receptors (VEGFR-1 and -2) has great importance in the healing process considering neovascularization. After a detailed analysis of the literature about radiotherapy effect in neovascularization and its relation with the expression of VEGF and VEGFR-1 and -2 in the healing, it was observed that there are many questions to be investigated. The objective of this study was to evaluate the immunohistochemical expression of VEGF and VEGFR-1 and -2 and sanguineous vessel density (DVS) after incision and cutaneous repairing in animals under influence of the radiotherapy at three and six months. This study used 60 Wistar rats randomly distributed in six groups: control, preoperative radiotherapy and postoperative radiotherapy, of 3 and 6 month each. The specimens evaluated macro/microscopically were removed after animal\'s sacrifice, in accordance to clinical ethics principles. The immunohistochemistry study of VEGFs were conducted using above-mentioned specific antibodies in manufacturer specified dilutions, while the study of the DVS was performed with the Von Willebrand Factor antibody (VWF) which was used to mark endothelial cells specifically. In both periods studied, surgical wound and radiation damages are similar in most cases. The primarily irradiated cases presented bizarre cellularity, multinucleated giant cells, stromal hyalinization structures, moderate to strong necrosis, overexpression of VEGF receptors in the endothelium and blood vessels in consequence of radiotherapy. These findings are in accordance to the literature, since the strong relationship between VEGFR-2 receptor and its persistence in neovascularization and granulation tissue formation were seen. Our results have shown that VEGF expression is constantly expressed in different times of wound healing and scar formation

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Bermudez, Yira. "Growth Factor-Mediated Telomerase Activity in Ovarian Cancer Cells". [Tampa, Fla.] : University of South Florida, 2007. http://purl.fcla.edu/usf/dc/et/SFE0002028.

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Gonçalves, Silvana Beltrami. "Efeito do VEGF na angiogênese pulpar e na apoptose". Universidade de São Paulo, 2006. http://www.teses.usp.br/teses/disponiveis/25/25138/tde-22062007-094740/.

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O fator de crescimento vascular endotelial (VEGF) desempenha um papel importante na angiogênese, induzindo a proliferação da célula endotelial, migração e sobrevivência. Com o intuito de promover a formação de novos vasos, e obter uma melhora na circulação colateral, VEGF tem sido utilizado para o tratamento de áreas de isquemia cardíaca, na doença cardiovascular. A manutenção da vitalidade pulpar com VEGF pode melhorar o prognóstico dos dentes que sofreram avulsão, prevenindo a perda precoce do dente. O propósito deste estudo foi desenvolver um modelo para se estudar o processo de revascularização da polpa dentária e avaliar o efeito do VEGF- 165 na angiogênese da polpa humana e na apoptose. Fatias de dente humano foram mantidas in vitro (cultura) com e sem VEGF (50ng/ml) durante 7 dias. Coloração de imuno-histoquímica para o Fator de Von Willebrand (Fator VIII) foi utilizada para quantificar o número de vasos sangüíneos no tecido pulpar. O número de vasos sangüíneos foi significantemente mais alto no grupo do VEGF (média -67.87) comparado ao grupo controle (média- 46.25, p< .05). O teste do Tunel foi usado para determinar o número de células apoptóticas nos grupos com e sem VEGF. Análises da expressão de VEGFR-2 por RT-PCR foram realizadas nas células endoteliais da microvasculatura da derme humana (HDMECs), células pulpares indiferenciadas (OD-21), células tipo odontoblasto de camundongo (MDPC-23) e macrófagos. A expressão de VEGFR-2 foi detectada nas HDMECs, mas não nas outras 3 linhas celulares. Quatro fatias de dente humano por camundongo imunodeprimido foram implantadas na região dorsal, subcutaneamente, pelo período de 7 dias. A vitalidade pulpar foi determinada pelas análises microscópica e imuno-histoquímica. O teste do Tunel foi usado para determinar o número de células apoptóticas. O modelo de angiogênese pulpar utilizando camundongos imunodeprimidos (SCID mouse model of pulp angiogenese) demonstrou ser um modelo viável para se estudar o processo de revascularização da polpa dentária humana. Levando-se em consideração os resultados obtidos neste estudo, sugere-se que o VEGF possa ter um efeito positivo na revascularização de dentes avulsionados. E que o modelo de angiogênese pulpar desenvolvido nesta pesquisa possa ser útil para responder a inúmeras novas questões experimentais na área de Endodontia.
The Vascular endothelial growth factor (VEGF) plays na important role in angiogenesis by inducing endothelial cell proliferation, migration, and survival. To promote new vessel formation and improve collateral circulation, VEGF has been used to treat ischemic heart areas in cardiovascular disease. Maintenance of pulp vitality with VEGF may improve the outcomes of avulsed teeth, preventing premature tooth loss. The purpose of this study was to develop a model system to study the process of dental pulp revascularization, and assess the effect of VEGF-165 in the human pulp angiogenesis and apoptosis. Human tooth slices were maintained in vitro for 7 days +/- VEGF (50ng/mL). Immunohistochemistry staining for Von Willebrand?s factor (Factor VIII) was used to quantify the number of vessels in pulp tissues. There was a significantly higher number of blood vessels in the VEGF group (67.8 Mean) compared to the control group (46.2 Mean, p<0.05). Tunel Assay was used to determine the number of apoptotic cells in +/- VEGF groups. RTPCR analyses of VEGFR-2 transcripts were used on human dermal microvascular endothelial cells (HDMECs), undifferentiated pulp cells (OD-21), mouse odontoblast-like cells (MDPC-23), and macrophages. VEGFR-2 expression was detected in HDMECs but not in the other 3 cell lines. Four tooth slices per mouse were subcutaneously implanted in the dorsal region for 7 days. Pulp vitality was determined by histological and immunohistochemical analysis. Also, Tunel Assay was used to determine the number of apoptotic cells. SCID mouse model of pulp angiogenesis demonstrated to be a good model system to study revascularization of human dental pulps. Taking into account the findings of this study, it is suggested that VEGF could have a positive effect in the revascularization of avulsed teeth. It is hoped that this pulp angiogenesis model be useful to answer a number of new experimental questions in the area of Endodontics.

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Meade, Eliza. "Hypoxic Regulation of VEGF and PAI-1 Expression by HIF-1[alpha] and HIF-2[alpha] in First Trimester Trophoblasts". Yale University, 2006. http://ymtdl.med.yale.edu/theses/available/etd-06282006-115727/.

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Preeclampsia results from incomplete trophoblast invasion of the spiral arteries during early pregnancy. Vascular endothelial growth factor (VEGF) and plasminogen activator inhibitor-1 (PAI-1) are critical factors involved in angiogenesis, invasion and hemostasis at the maternal-fetal interface. Both factors are transcriptionally regulated by hypoxia inducible factor (HIF), a heterodimeric complex consisting of HIF-1[beta] and either HIF-1[alpha] or -2[alpha] whose specificity or redundancy in gene regulation is cell-type specific. This study uses siRNA technology to dissect the mechanisms of hypoxia-mediated regulation of PAI-1 and VEGF expression in first trimester trophoblasts. Immortalized first trimester human extravillous trophoblasts (HTR8/SVneo cells) were maintained in serum-free and serum-containing media for 4h (n=3-4), 8h (n=6), 24h (n=5) and 48h (n=5) under normoxic (21% O2) and hypoxic (1-2% O2) conditions to determine a time of maximum induction of both VEGF and PAI-1. Subsequently, cells were maintained for 48h in the presence or absence of siRNA for HIF-1[alpha], HIF-2[alpha], HIF-1[alpha] + -2[alpha], a non-targeting (NT) sequence or Cyclophilin B (CB). Media were then removed, cells lysed, and Western blotting used to assess HIF-[alpha] knockdown. VEGF and PAI-1 levels in the media were quantified by ELISA and results expressed as pg or ng/[micro]g protein. Results from 3 to 8 independent experiments were analyzed using unpaired t-tests. Under hypoxic conditions treatment of cells with HIF-1[alpha], HIF-2[alpha] or HIF -1[alpha] + -2[alpha] siRNA resulted in >90% HIF-Ñ protein knockdown as determined by Western blotting. 48h of hypoxic treatment caused a statistically significant increase in PAI-1 levels (p<0.01) and VEGF levels (p<0.001) compared to normoxic controls. Under hypoxic conditions, PAI-1 levels were 4.75 [plus-minus] 0.46 ng/[micro]g protein and VEGF levels were 7.27 [plus-minus] 1.08 pg/[micro]g protein. Treatment with siRNA to HIF-1[alpha], HIF-2[alpha] and HIF-1[alpha] + -2[alpha] significantly reduced PAI-1 levels to 3.3 [plus-minus] 0.35 (p<0.02), 3.1 [plus-minus] 0.38 (p<0.03) and 2.4 [plus-minus] 0.19 (p<0.003), respectively. No significant difference in PAI-1 reduction was noted between the three HIF siRNA conditions. Under hypoxic conditions, levels of VEGF in cells treated with siRNA to HIF-1[alpha] (5.79 [plus-minus] 0.55), HIF-2[alpha] (5.50 [plus-minus] 1.24) and HIF-1[alpha] + -2[alpha] (4.24 [plus-minus] 0.93) were reduced compared to the hypoxic control (7.27 [plus-minus] 1.08), yet these effects did not reach statistical significance. However, when compared with the levels observed in cells treated with NT siRNA (9.90 [plus-minus] .98), all HIF siRNA treatments promoted a significant reduction in VEGF expression (p<0.003, p<0.02 and p<0.003 for HIF-1[alpha], HIF-2[alpha] and HIF-1[alpha]+ -2[alpha], respectively). In conclusion, these results indicate that hypoxia-mediated changes in PAI-1 and VEGF expression in trophoblasts are regulated similarly by both HIF-1[alpha] and HIF-2[alpha]. This provides important insight into the molecular mechanisms regulating hemostasis and trophoblast invasion as well as their potential dysfunction in pregnancies complicated by preeclampsia

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Alves, Brunna Eulálio 1979. "Avaliação de moduladores do aumento da permeabilidade microvascular e sua correlação com a evolução clínica na sepse em pacientes onco-hematológicos neutropênicos febris". [s.n.], 2011. http://repositorio.unicamp.br/jspui/handle/REPOSIP/309168.

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Orientador: Erich Vinicius de Paula
Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas
Made available in DSpace on 2018-08-18T13:46:04Z (GMT). No. of bitstreams: 1 Alves_BrunnaEulalio_D.pdf: 4762678 bytes, checksum: 34eea414d90830a52ed9c9b044538888 (MD5) Previous issue date: 2011
Resumo: Pacientes portadores de neoplasia hematológica e neutropenia febril representam um grupo de risco elevado de sepse e choque séptico. Nas últimas décadas, estratégias terapêuticas alvo-específicas para a sepse não modificaram de forma significativa a sobrevida dos pacientes e o tratamento permanece baseado em antibioticoterapia e cuidados de suporte, com altas taxas de mortalidade. A quebra da barreira endotelial é um evento fundamental na fisiopatologia do choque séptico e a compreensão dos mecanismos envolvidos neste evento tem o potencial de auxiliar na identificação de novos biomarcadores de gravidade e de novos alvos terapêuticos para estes pacientes. Estudos recentes demonstraram a participação do fator de crescimento do endotélio vascular (VEGF-A), do seu receptor solúvel (sFlt-1) e das angiopoietinas 1 e 2, proteínas envolvidas na angiogênese e na regulação da integridade da barreira endotelial na fisiopatogenia do choque séptico em pacientes não oncológicos internados em unidade de terapia intensiva. Neste trabalho, avaliamos prospectivamente a cinética do VEGF-A, do sFlt-1 e das angiopoietinas 1 e 2 durante as 48 horas inicias da neutropenia febril em 41 pacientes portadores de neoplasia hematológica submetidos a quimioterapia intensiva ou a regime de condicionamento para transplante de células progenitoras hematopoiéticas, através da dosagem dos mesmos por ensaio imuno-enzimático. Exploramos também a associação dos níveis séricos destes biomarcadores com a gravidade da sepse através da correlação com o MASCC, um índice desenvolvido para identificar pacientes com neutropenia febril de baixo risco, e com o SOFA, um escore de avaliação de disfunção orgânica em pacientes com sepse, ambos amplamente aceitos. A evolução para choque séptico foi associada a níveis significativamente maiores de VEGF-A, sFlt-1 e angiopoietina-2 48 horas após o início da neutropenia febril quando comparado aos valores em pacientes com sepse não complicada e a estimativa da acurácia diagnóstica sugere a capacidade de discriminar os pacientes que evoluíram com choque séptico. Estes biomarcadores também apresentaram correlação com os escores gravidade, sugerindo a relevância biológica da associação. Em conclusão, nossos achados sugerem que a avaliação destes biomarcadores em pacientes com neutropenia febril deve ser avaliada em estudos com maior número de pacientes, quanto ao seu potencial de incorporação na prática clínica. Além disso, os resultados reforçam o potencial terapêutico da intervenção nestas vias para o tratamento da sepse
Abstract: Patients with hematologic malignancy and neutropenia represent a group at high risk of sepsis and septic shock. In recent decades, target-specific therapeutic strategies for sepsis did not change significantly the survival of patients and treatment is still based on antibiotic therapy and supportive care, with high mortality rates. The breakdown of the endothelial barrier is a key event in the pathophysiology of septic shock and understanding of the mechanisms involved in this event has the potential to assist in the identification of new biomarkers and severity of new therapeutic targets for these patients. Recent studies have demonstrated the involvement of endothelial growth factor (VEGF-A), its soluble receptor (sFlt-1) and angiopoietins 1 and 2, proteins involved in angiogenesis and in regulation of endothelial barrier integrity in the pathogenesis of shock septic patients without cancer admitted to the intensive care unit. In this study, we prospectively evaluated the kinetics of VEGF-A, sFlt-1 and angiopoietins 1 and 2 during the initial 48 hours of febrile neutropenia in 41 patients with hematological malignancy undergoing intensive chemotherapy or conditioning regimen for stem cell transplantation hematopoietic cells by the same dosage by enzyme immunoassay. We also explored the association of serum levels of these biomarkers with the severity of sepsis through correlation with the MASCC, an index developed to identify patients with febrile neutropenia at low risk, and the SOFA score for assessment of organ dysfunction in patients with sepsis, both widely accepted. Progression to septic shock was associated with significantly higher levels of VEGF-A, sFlt-1 and angiopoietin-2 48 hours after the onset of febrile neutropenia when compared to values in patients with uncomplicated sepsis and the estimation of diagnostic accuracy suggests the ability to discriminate among patients who developed septic shock. These biomarkers also correlated with the severity scores, suggesting the biological relevance of the association
Doutorado
Clinica Medica
Doutor em Clínica Médica

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Agra, Ivan Marcelo Gonçalves. "Recidiva local de carcinomas epidermóides da boca e orofaringe: estudo de variáveis anatomopatológicas e de marcadores biológicos associados ao prognóstico em pacientes submetidos à cirurgia de resgate". Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/5/5155/tde-24012008-140634/.

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INTRODUÇÃO: Recidivas locais e loco-regionais são as principais causas de falha do tratamento em pacientes portadores de carcinomas epidermóides de boca e orofaringe. A cirurgia de resgate é geralmente a melhor opção terapêutica para esses pacientes. Esse estudo tem por objetivo avaliar a importância prognóstica da expressão das proteínas EGFR, MMP-2, MMP-9 e VEGF em pacientes com recidiva local submetidos à cirurgia de resgate. CASUÍSTICA E MÉTODOS: Os prontuários de 111 pacientes portadores de recorrência local de carcinomas epidermóides de boca e orofaringe foram analisados de forma retrospectiva. A localização do tumor primário foi o lábio em 10 casos (9%), a cavidade oral em 68 (61%) e a orofaringe em 33 (30%). O tratamento prévio foi cirurgia em 33 casos (30%), radioterapia associada ou não à quimioterapia baseada em cisplatina em 46 (41%) e cirurgia com radioterapia adjuvante em 32 (29%). A expressão das proteínas EGFR, MMP-2, MMP-9 and VEGF foi avaliada com a técnica do Tissue Microarray. RESULTADOS: O intervalo livre de doença variou de 0,89 a 140,9 meses, com uma mediana de 6,87 meses. As recidivas foram diagnosticadas em intervalo de tempo inferior a 1 ano em 69 pacientes (62,2%) e após 1 ano em 42 (37,8%). Os pacientes com intervalo livre de doença inferior a 1 ano apresentaram pior resultado de sobrevida (p=0,01). O estádio clínico da recidiva (rEC) foi I ou II em 31 casos (27,9%) e III ou IV em 80 (72,1%). Pacientes com doença em estádio clínico mais avançado (rEC III ou IV) apresentaram piores taxas de sobrevida específica por câncer (p=0,04). Hiper-expressão do EGFR foi associada a pior resultado do tratamento. Os casos com EGFR positivo obtiveram sobrevida específica por câncer em 3 anos de 27,2%, enquanto pacientes com EGFR negativo alcançaram 64,3% de sobrevida em 3 anos (p=0,001). A expressão das proteínas MMP-2, MMP-9 e VEGF não se mostrou significativa para o prognóstico (p=0,83, p=0,15 e p=0,86, respectivamente). Na análise multivariada, apenas o intervalo livre de doença e a expressão do EGFR foram associadas à maior risco de morte. CONCLUSÕES: Recidivas locais de carcinomas epidermóides de boca e orofaringe são associadas a mau prognóstico. Intervalo livre de doença superior a 1 ano e ausência de expressão do EGFR foram os principais fatores associados a melhores resultados de sobrevida específica por câncer em pacientes submetidos à cirurgia de resgate.
INTRODUCTION: Local and regional relapses are the main sites of treatment failure in patients with oral and oropharyngeal squamous cell carcinoma. In these instances, salvage surgery is the most widely used treatment approach. The aim of this study is to analyze the prognostic effect of the expression of EGFR, MMP-2, MMP-9 and VEGF in patients with recurrent cancer sumitted to salvage surgery. METHODS: The charts of 111 patients with local recurrence of oral or oropharyngeal squamous cell carcinomas were retrospectively analyzed. The tumor sites were: the lip in 11 cases (9%), the oral cavity in 68 (61%) and the oropharynx in 33 (30%). The previous treatment was: Surgery in 33 patients (30%), radiotherapy with or without cisplatin based chemotherapy in 46 (41%) and surgery with adjuvant radiotherapy in 32 (29%). EGFR, MMP-2, MMP-9 and VEGF expressions were analyzed with tissue microarray immunohistochemical technique. RESULTS: The disease-free interval ranged from 0.89 to 140.9 months with a median of 6.87 months. The patients were categorized into two groups: Those with recurrence in less than 1 year (69 patients - 62.2%) and those with recurrence after 1 year (42 - 37.8%). The group with the shorter disease-free interval presented a worse prognosis (p=0.01). The clinical stage of recurrence (rCS) was I/II in 31 cases (27.9%) and III/IV in 80 cases (72.1%). Patients with more advanced diseases (rCS III/IV) had worse rates of cancer specific survival (CSS) than patients with rCS I/II (p=0.04). An over-expression of EGFR was associated with worse treatment results. Positive EGFR cases had a 3 year CSS of 27.2%, while EGFR negative patients had 64.3% (p=0.001). The MMP-2 and MMP-9 over-expression were also associated with a worse prognosis but without statistical significance (p=0.83 and p=0.15). VEGF expression did not show prognostic significance in this group of patients. In a multivariate analysis only the disease-free interval and over-expression of EGFR were associated with a higher risk of death. CONCLUSION: Local recurrence in oral and oropharyngeal squamous cell carcinomas usually indicates an unfavorable prognosis. A disease-free interval greater than 1 year and a negative EGFR expression are the main prognostic factors which indicate a better cancer specific survival rate in patients submitted to salvage surgery.

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Arantes, Ricardo Vinicius Nunes. "Estudo da angiogênese e da expressão temporal do VEGF e dos seus receptores VEGFR-1/Flt-1 e VEGFR-2/Flk-1 durante o reparo ósseo alveolar normal e com uso terapêutico de um antiinflamatório não esteroidal seletivo para COX-2 em ratos". Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/25/25149/tde-12062012-151744/.

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Objetivo: Avaliar o efeito do Meloxicam sobre a expressão do VEGF e de seus receptores durante o reparo alveolar pós-exodontia em ratos. Material e Método: Foi realizada a exodontia do incisivo superior direito em 180 ratos Wistar, machos, com 60 dias de idade, subdivididos em dois grupos: 1) Grupo controle (n=90): os animais receberam injeção intraperitoneal de 0,1 ml de solução 0.9% NaCl diariamente, durante 7 dias; e 2) Grupo experimental (n=90): os animais receberam injeção diária de 3mg/kg de massa corporal de Meloxicam em solução 0.9%NaCl, durante 7 dias. Após 3, 7, 10, 14, 21 e 30 dias, os alvéolos foram coletados, fixados em formol a 10% em tampão fosfato, radiografados e processados histologicamente. Para o PCR-RT, as peças foram colocadas em Trizol® e armazenadas a -80ºC e para o Western blotting armazenado a -80ºC. Cortes histológicos semi-seriados (250m de intervalo entre os cortes) de todo o alvéolo no sentido transversal foram obtidos e corados pela hematoxilina e eosina. Avaliou-se nesses cortes pelo método morfométrico de volumetria de pontos a densidade de volume de tecido ósseo (%TO), tecido conjuntivo (%TC), coágulo sanguíneo (%Coa) e vaso sanguíneo (%VS). Os dados obtidos foram submetidos ao teste t para comparação entre os grupos por período e a ANOVA seguido do teste de Tukey para comparação entre períodos dentro de cada grupo, adotando nível de significância de p<0,05. Resultados: A análise radiográfica mostrou ocorrência com o transcorrer do tempo alterações no contorno da cortical óssea e redução no tamanho do alvéolo, além de um pequeno aumento na radiodensidade na região central do alvéolo. Morfologicamente, o grupo experimental exibiu em todos os períodos analisados, um atraso no processo de reparo em relação ao controle, exibindo maior quantidade de coágulo sanguíneo com lenta substituição por tecido conjuntivo e menor reabsorção da cortiça óssea alveolar e da formação/remodelação óssea. Na análise morfométrica a %TO no grupo controle foi de 0.817, 0.255, 0.368, 0.409 e 0.453 vezes maior em relação ao grupo experimental nos períodos de 3, 7, 10, 14 e 21 dias, respectivamente. Quanto a %Coa, os valores no grupo controle foram 0,097, 0,611, 1,189 e 1.497 vezes menor em relação ao grupo experimental nos períodos de 7, 10, 14 e 21 dias,respectivamente. A %VS no grupo controle apresentou 0,328 e 0,439 vezes maiores em relação ao grupo experimental nos períodos de 10 e 14 dias, respectivamente. A %TC não apresentou diferença estatística entre os grupos. As imunomarcações para VEGF e VEGFR-1 foram observadas em osteoblastos e osteócitos na cortical alveolar, e em fibroblastos no interior do alvéolo, com diferença estatisticamente significante apenas para VEGFR-1, onde a imunomarcação no grupo controle foi 0,544; 0,325 e 0,325 vezes maior em relação ao grupo experimental nos períodos de 3, 7 e 10 dias, respectivamente. As análises do PCR-RT para VEGF no grupo controle foi 1,274 vezes maior no período de 10 dias em relação ao grupo experimental. Na expressão de RNAm para VEGFR-1, o grupo controle foi 1,431; 0,951 e 0,845 vezes maior nos períodos de 3, 10 e 30 dias, respectivamente, em relação ao grupo experimental e VEGFR-2 no grupo controle de 4,649 e 0,790 vezes maior nos períodos de 3 e 7 dias, respectivamente. A expressão protéica do VEGF no grupo controle foi 0,365; 1,056; 2,187 e 0,350 vezes maior nos períodos de 3; 7; 10 e 14 dias em relação ao grupo experimental. Conclusões: Com base nos resultados obtidos foi possível concluir que o uso do antiinflamatório Meloxicam, administrado diariamente por 7 dias, altera a expressão do RNAm e das proteínas do VEGF e de seus receptores VEGFR, além de atrasar o processo de reparo e de remodelação óssea alveolar pós-exodontia.
Objective: To evaluate the effect of Meloxicam on the expression of VEGF and its receptors during the post-extraction alveolar healing in rats. Material and Methods: The extraction of the right upper incisor was made in 180 male Wistar rats, aged 60 days old. The sample was divided in: 1) Control group (n=90) - the rats received intraperitoneal injection of 0.1 ml of 0.9% NaCl daily for 7 days, and 2) experimental group (n=90) - the rats received intraperitoneally 3mg/kg body weight of Meloxicam in 0.9% NaCl solution daily for 7 days. At 3, 7, 10, 14, 21 and 30 days later, the alveolar samples were collected, fixed in 10% formaldehyde in phosphate buffer, radiographed and histologically processed. For RT-PCR, the samples were placed in Trizol and stored at -80° and for Western blotting stored at -80°. Transversal semi-serial histological sections (with 250 um interval) of the whole alveolus were obtained and stained with hematoxylin and eosin. In these sections the volume density of bone tissue (% TO), connetive tissue (% CT), blood clot (Coa%) and blood vessel (% VS) was evaluated by point counting volumetry morphometric method. The obtained data were compared between groups for period by \"t\" test and between periods within each group by ANOVA and Tukey test, with a p<0.05 significance level. Results: a) The radiographic analysis showed changes in the contour of the cortical alveolar bone , reduction in size of the alveolus, and a small increase in radiodensity in their central region ; b) Morphologically the experimental group showed, in all periods, a delay in the repair process as compared to control, displaying greater amount of blood clot with slow replacement by connective tissue and lower cortical alveolar bone resorption and bone formation / remodeling c) In morphometric analysis the %TO in the control group were 0.817, 0.255, 0.368, 0.409 and 0.453 times higher than the experimental group during periods of 3, 7, 10, 14 and 21 days , respectively. The %Coa, the values in the control group were 0,097, 0,611, 1,189 and 1.497 times lower than in the experimental group on days 7, 10, 14 and 21 days respectively. The %VS in the control group showed 0.328 and 0.439 times higher than in the experimental group on days 10 and 14 days respectively. The% CT showed no statistical difference between groups. d) The imumunostaining for VEGF and VEGFR-1 were observed in osteoblasts and osteocytes in the cortical alveolar, and fibroblasts within the alveolus, which was statistically significant only for VEGFR-1, where the immunostaining in the control group was 0,544; 0,325 and 0,325 times higher than the experimental group during periods of 3, 7 and 10 days respectively e) The RT-PCR analysis for VEGF in the control group was 1.274 times higher within 10 days compared to the experimental group. In the expression of mRNA for VEGFR-1, the control group was 1,431; 0,951 and 0,845times higher in periods of 3, 10 and 30 days, respectively, compared to the experimental group and VEGFR-2 was 4.64 and 0.79 times higher in periods of 3 and 7 days, respectively, and f) The protein expression of VEGF in the control group was 0,365; 1,056; 2,187 and 0,350 times higher in periods of 3, 7, 10, 14 and 21 days compared to the experimental group. Conclusions: Based on the present results it was concluded that the use of Meloxicam, antiinflammatory administered daily for 7 days, alters the expression of mRNA and protein of VEGF and its receptors VEGFR, and slows the process of repair and remodeling post extraction alveolar

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27

Rotter, Anita. "Avaliação dos níveis plasmáticos e urinários do fator de crescimento do endotélio vascular e dos níveis urinários das metaloproteinases 2 e 9 em pacientes com hemangioma infantil antes e durante o tratamento com betabloqueador sistêmico e tópico". Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/5/5133/tde-16022018-083833/.

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INTRODUÇÃO: Fatores angiogênicos têm sido estudados em relação ao seu papel na patogênese do hemangioma da infância (HI). Durante o tratamento com betabloqueador, os pacientes com HI são acompanhados por exame físico e comparações por fotografia e ultrassonografia. Além disso, a dosagem sanguínea e urinária do fator de crescimento do endotélio vascular (VEGF) e a dosagem urinária das metaloproteinases 2 e 9 (MMP-2 e 9) podem ser ferramentas não invasivas para o acompanhamento evolutivo e terapêutico do HI. OBJETIVOS: Estudar os níveis de VEGF plasmático e urinário e MMP- 2 e MMP-9 urinárias em pacientes com HI, com o objetivo de avaliar sua possível relação na angiogênese do HI. MÉTODOS: foram incluídos 68 pacientes com hemangioma infantil e 25 controles, pareados por idade e sexo. Foi instituído tratamento sistêmico com propranolol em 45 crianças e tópico, com timolol, em 23. Os pacientes foram acompanhados por até 12 meses de tratamento com medidas de volume do HI pela ultrassonografia, dosagem plasmática e urinária de VEGF e dosagem urinária de MMP-2 e MMP-9 (ensaio Luminex). RESULTADOS: Os níveis de MMP-2 foram indetectáveis em mais de 50% das amostras. Antes do início do tratamento, não houve diferença dos níveis plasmáticos e urinários de VEGF e urinários de MMP-9 entre os grupos de pacientes com HI e controles. Não foi encontrada diferença significativa nos níveis plasmáticos e urinários dos biomarcadores de acordo com a fase de crescimento do hemangioma (crianças com 12 meses ou menos, em relação às maiores que 12 meses de idade). Não houve correlação entre o tamanho do HI e os níveis dos biomarcadores. Obteve-se correlação positiva significativa entre os níveis urinários de VEGF e MMP-9. No grupo tratado com propranolol, observou-se diminuição significativa do volume do HI com o tratamento, o que não foi verificado no grupo tratado com timolol. A variação dos valores dos biomarcadores obtidas antes, até seis meses e de sete a doze meses de tratamento, mostrou redução significativa de VEGF plasmático e MMP-9 urinária nas crianças tratadas com propranolol. Não foi observada variação significativa dos níveis dos biomarcadores durante o tratamento com timolol. CONCLUSÕES: os níveis plasmáticos e urinários de VEGF e os níveis urinários de MMP-9 não se mostraram bons marcadores de angiogênese aumentada nos pacientes com HI, nem tampouco refletiram o aumento da angiogênese característica da fase proliferativa do HI. No acompanhamento terapêutico dos HIs tratados com propranolol, a medida dos níveis dos biomarcadores mostrou diminuição significativa de VEGF plasmático e MMP-9 urinária, o que não foi observado com o timolol. A redução do volume do HI associada à diminuição dos biomarcadores nos pacientes tratados com propranolol sugeriu que o mecanismo de ação do betabloqueador nos HIs seja também por inibição da angiogênese. Desse modo, as dosagens de VEGF plasmático e MMP-9 urinária podem ser úteis para monitorar a efetividade do tratamento
INTRODUCTION: Angiogenic factors have been studied in regard to their role in the pathogenesis of infantile hemangioma (IH). During ß-blocker treatment, patients were monitored through physical examination and comparisons by photography and ultrasonography. In addition, plasma and urinary levels of vascular endothelial growth factor (VEGF) and urinary levels of matrix metalloproteinases 2 and 9 (MMP-2 and MMP-9) can be non-invasive tools to monitor the evolution of IH and its therapeutic follow-up. OBJECTIVES: To study plasma and urinary levels of VEGF and urinary levels of MMP-2 and MMP-9 in patients with IH, in order to evaluate their potential relation to the IH angiogenesis. METHODS: 68 IH patients and 25 controls were included, matched by age and gender. Systemic treatment with propranolol was administered to 45 patients, while topical timolol was administered to 23 patients. Patients were monitored for up to 12 months of treatment with measurements of IH volume through ultrasonography, plasma and urinary levels of VEGF and urinary levels of MMP-2 and MMP-9 (Luminex assays). RESULTS: MMP-2 levels were not detectable in over 50% of the samples. Before treatment, there was no difference in plasma and urinary levels of VEGF and urinary levels of MMP-9 between IH patients and control group. There was no significant difference in plasma and urinary levels for the biomarkers in accordance to the proliferative phase (12-month-old children or younger, in relation to children over 12 months of age). There was no correlation between IH size and biomarkers levels. There was a significant correlation between urinary levels of VEGF and MMP-9. In the propranolol group, a significant reduction of the IH volume with treatment was observed; this was not observed in the group treated with timolol. The variation of the biomarkers values obtained before, up to six months and from seven to twelve months of treatment indicated significant decrease in plasma levels of VEGF and urinary levels of MMP-9 in children treated with propranolol. It was not observed a significant variation of the biomarkers levels during timolol treatment. CONCLUSIONS: Plasma and urinary levels of VEGF and urinary levels of MMP-9 were not good markers of increased angiogenesis in patients with IH, nor reflected the increase in angiogenesis characteristic of the proliferative phase of IH. During therapeutic monitoring of IH treated with propranolol, a significant decrease in plasma VEGF and urinary MMP-9 levels was observed. The reduction in volume associated to the decrease in biomarkers in patients treated with propranolol suggested that its mechanism of action in IH occurs also through the inhibition of the angiogenesis. Thus, measurements of plasma levels of VEGF and urinary levels of MMP-9 may be useful to monitor the effectiveness of treatment

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Roberts, Selene Karen. "Signalling via vascular endothelial growth factor receptor complexes". Thesis, University of Leicester, 2005. http://hdl.handle.net/2381/29705.

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This study sought to investigate the role of various components of VEGF receptor signalling complexes using fluorescence microscopy to complement conventional biochemical techniques. Using DsRedII-Grp1 to visualise the product of the reaction catalysed by PI3K, activation of PI3K downstream of VEGF receptor-2 is shown. There was no obvious relocalisation of p85 to phosphorylated receptors however a small amount of GFP-p85 associates with, and is phosphorylated in response to, activated VEGF receptor-2. The Shc-related adaptor ShcB/Sck was localised to the plasma membrane in stimulated endothelial cells and associated with activated VEGF receptor-2. PTB and SH2 protein domains, contained within Sck, facilitated these events. Key tyrosine amino acids found within Grb2 binding motifs of ShcA and Sck were phosphorylated in response to VEGF. Tyrosine residues 315 and 316 of Sck were phosphorylated to a greater extent when compared to the corresponding residues of ShcA. Cells expressing Sck proteins lacking tyrosine phosphorylation sites showed a reduced amount of phospho-ERK and DNA synthesis. VEGF receptor-2 was internalised and degraded in response to VEGF. This occurred, at least in part, through the conventional endocytic pathway. VEGF receptor-2 is localised in caveolin-1 and EEA-1 containing vesicles, which is suggestive of internalisation via caveolae and/or early endosomes. Nedd4 co-localises with VEGF receptor-1 at regions of the plasma membrane and this association was confirmed by co-immunoprecipitation. The over-expression of Nedd4 enhanced the degradation of VEGF receptor-1.

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Suzuma, Izumi. "Stretch-induced retinal vascular endothelial growth factor expression is mediated by phosphatidylinositol 3-kinase and protein kinase c (PKC)-ζ but not by stretch-induced ERK1/2, Akt, Ras, or classical/novel PKC pathways". Kyoto University, 2004. http://hdl.handle.net/2433/147489.

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30

Krishnan, Jaya. "The role of vascular endothelial growth factor receptor 3, and its ligands vascular endothelial growth factor C and vascular endothelial growth factor D in tumour metastasis and haematopoeisis". Thesis, University of London, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.270576.

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31

Groot, Marcel. "Die Rolle des Tyrosinkinase-Rezeptors VEGFR-2 im neuronalen Kontext". Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2006. http://nbn-resolving.de/urn:nbn:de:swb:14-1166623362738-03904.

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Im Rahmen dieser Arbeit wurde die Rolle des Rezeptors VEGFR-2, Flk-1, im neuronalen Kontext untersucht. In einem ersten Schritt wurde in embryonalen Stammzellen der Maus das fluoreszierende Protein eGFP unter der Kontrolle regulatorischer Sequenzen des flk-1-Promotors, -Enhancers exprimiert. Nach der Differenzierung zu Sphäroiden wurden Endothelzellen nachgewiesen, die sowohl eGFP als auch das zelltypspezifische Oberflächenantigen CD31 ausprägen. Ebenso wurden nach der neuronalen Differenzierung in Gegenwart von Stromazellen eGFP-exprimierende Zellen identifiziert. Diese standen mit Zellen, die das für neuronale Vorläuferzellen charakteristische Protein Nestin ausprägten, in einem räumlichen Zusammenhang. Die Vorgehensweise, die Inaktivierung des flk-1-Gens mit der Differenzierung embryonaler Stammzellen in vitro zu kombinieren, sollte hier die Interpretation des Phänotyps des flk-1-defizienten Mausmodells ermöglichen. Der Rezeptor war während der neuronalen Differenzierung der Stammzellen auf Stromazellen in vitro für die Regulation der Anzahl der Vorläuferzellen essentiell. Ferner spielte der Rezeptor im Rahmen eines weiteren Differenzierungsmodells, das auf der Zugabe relevanter Wachstumsfaktoren beruht, eine instruktive Rolle im Hinblick auf die Identität der Neuronen. Kriterium war hier die differentielle Expression Homeobox-enthaltender Transkriptionsfaktoren. In einem zweiten Schritt wurden mit Hilfe dieses Modells differentiell-exprimierte Gene von Stammzellen des Wildtyps sowie Zellen mit einer Inaktivierung des flk-1-Gens nach der neuronalen Differenzierung durch subtraktive Hybridisierung in Verbindung mit der PCR identifiziert. Tatsächlich wurde das Protein PEA-15 nicht nur differentiell exprimiert sondern auch als Bestandteil des VEGFR-2-vermittelten Signalwegs identifiziert. Die biologischen Funktionen des Proteins PEA-15 wurden durch VEGF-vermittelte Phosphorylierung reguliert. Die Stimulation durch VEGF führte zunächst zu einer Aktivierung des Proteinkinase B-, Akt-Signalwegs. Für die Stimulation des Akt-Signalwegs war die Phosphorylierung der intrazellulären Tyrosinreste Y1052 und Y1057 des Rezeptors essentiell. Damit einhergehend wurde PEA-15 gegenüber der proteasomalen Degradation stabilisiert. Es wurde gezeigt, daß das Protein PEA-15 die Teilungsaktivität von Zellen beeinflusst. Die VEGF- vermittelte Stimulation führte zur Phosphorylierung der Mitogen-aktivierten Proteinkinasen ERK1 und ERK2. Die weitere Phosphorylierung der Substrate dieser Kinasen im Zellkern wurde durch Interaktion mit PEA-15 unterdrückt. Die Regulation des c-fos-Promotors war zugleich Indikator der Inhibition der Phosphorylierung betreffender Substrate sowie der proliferativen Aktivität. Auf diese Weise ist die Phosphorylierung von PEA-15 nach Stimulation durch VEGF für die Selektivität des Flk-1-vermittelten Signalwegs von unmittelbarer Bedeutung. Die Regulation der biologischen Funktion von PEA-15 erklärt die differentielle Ausprägung im Rahmen der neuronalen Differenzierung embryonaler Stammzellen in vitro. So war die Anzahl GFAP- beziehungsweise PEA-15-exprimierender Zellen nach Differenzierung muriner Stammzellen mit einer Inaktivierung des flk-1-Gens deutlich geringer. Die differentielle Expression identifizierter Gene wurde im Mausmodell nach konditionaler Inaktivierung des flk-1-Gens überprüft. Tatsächlich wurde Vimentin in verschiedenen Arealen des Gehirns differentiell ausgeprägt. Ein Zusammenhang zwischen der differentiellen Expression des Proteins PEA-15, der Anzahl GFAP-exprimierender Zellen und der Ausprägung des Rezeptors Flk-1 ergab sich aus der Identifikation einer Zellpopulation in der subgranulären Zone des Gyrus Dentatus. Dort wurde in flk-1-defizienten, adulten Mäusen eine geringere Anzahl GFAP-exprimierender Zellen nachgewiesen. Schließlich wurden sowohl im Cerebellum als auch im Cortex histologische Unterschiede deutlich, die sich im adulten Organismus aus der Inaktivierung des Rezeptors Flk-1 ergeben. Die vorliegende Arbeit zeigt, daß der Rezeptor VEGFR-2, Flk-1, im neuronalen Kontext eine Rolle spielt, die sich nicht ausschließlich auf die Vermittlung eines Schutzmechanismus gegenüber der neuronalen Apoptose beschränkt, sondern auch auf eine Beteiligung an der Neurogenese hinweist. Die Vorgehensweise, mit Hilfe der subtraktiven Hybridisierung Bestandteile Rezeptor-vermittelter Signalwege vor dem Hintergrund der Differenzierung embryonaler Stammzellen zu identifizieren, verdeutlicht die Eignung der Methode auch bei komplexen Zellpopulationen.

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Garvin, Stina. "Effects of sex steroids and tamoxifen on VEGF in the breast". Doctoral thesis, Linköping : Linköping University, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-7230.

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33

Mahlman, M. (Mari). "Genetic background and antenatal risk factors of bronchopulmonary dysplasia". Doctoral thesis, Oulun yliopisto, 2018. http://urn.fi/urn:isbn:9789526219530.

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Abstract Advances over the past few decades in ante- and neonatal care have led to the survival of a growing number of premature infants of extremely low gestational age. However, the occurrence of serious diseases, particularly those affecting the most immature infants, remains high. Bronchopulmonary dysplasia (BPD), a chronic lung disease of premature infants, is one such disease. Our current understanding of the molecular pathogenesis of BPD is incomplete; consequently, there are few preventive and therapeutic options for BPD. Moreover, it is challenging to predict the risk of BPD. Previous studies of BPD in twins revealed that the heritability of BPD is quite high. However, the individual genes that predispose premature infants to BPD are largely unknown. The aim of this study was to identify and study genes associated with BPD in order to investigate its pathogenesis. An additional aim was to add to knowledge of the risk of BPD in newborn premature infants, with an emphasis on twins. A candidate gene study found no consistent association between common polymorphisms of vascular endothelial growth factor receptor 2 and BPD. A second candidate gene study noted an association between the gene encoding Kit ligand and BPD. A genome-wide association study found a suggestive association between a locus close to the gene encoding C-reactive protein (CRP) and BPD, and in subsequent analyses, plasma levels of CRP during the first week of life predicted BPD. Finally, a nationwide register study found that the risk of BPD was lower in twins than in singletons. The results of this study add to what is known of the genetics and pathogenesis of BPD. They also provide new data on the risk of BPD, which may be used to improve early identification of infants for whom the risk of developing BPD is high
Tiivistelmä Ennenaikaisen syntymän ja keskoslasten hoidon kehittymisen myötä yhä useammat huomattavan epäkypsinä syntyneet lapset jäävät henkiin. Samalla erityisesti juuri näitä lapsia uhkaavien sairauksien esiintyvyys on pysynyt korkeana. Bronkopulmonaalinen dysplasia (BPD, keskosen krooninen keuhkosairaus) on yksi näistä sairauksista. BPD:n molekyylitasoinen tautimekanismi on vielä osin tuntematon, eikä BPD:tä tehokkaasti estävää tai siitä parantavaa hoitoa ole. Myös BPD riskin arvioiminen vastasyntyneen keskoslapsen kohdalla on vaikeaa. BPD on huomattavan perinnöllinen tauti. BPD:lle altistavista geeneistä on kuitenkin vasta vähän tietoa. Tämän tutkimuksen tavoitteena oli lisätä tietoa BPD:n tautimekanismista tutkimalla BPD:lle altistavia geenejä. Lisäksi tutkimuksessa tarkasteltiin BPD:n esiintyvyyttä ja syntymää edeltäviä riskitekijöitä erityisesti kaksosten osalta. Ehdokasgeenitutkimuksessa verisuonten endoteelikasvutekijää koodaava geeni ei assosioitunut toistuvasti BPD:hen. Kit ligandia koodaava geeni sen sijaan assosioitui. Koko genomin assosiaatiotutkimuksessa C-reaktiivista proteiinia (CRP) koodaavan geenin lähistöltä löydettiin BPD:hen mahdollisesti assosioituva alue. Lisäksi ensimmäisen viikon CRP-arvojen osoitettiin ennakoivan myöhemmin kehittyvää BPD:tä. BPD-riskin todettiin olevan matalampi kaksi- kuin yksisikiöisistä raskauksista syntyneillä lapsilla. Tutkimuksen tulokset lisäävät tietoa BPD:n perinnöllisyydestä ja sitä kautta BPD:n tautimekanismista. Tutkimus toi myös uutta tietoa BPD:n riskitekijöistä parantaen vastasyntyneen keskoslapsen BPD-riskin arviota

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Wendt, Astrid [Verfasser]. "Korrelation von placental growth factor, vascular endothelial growth factor und soluble vascular endothelial growth factor receptor-1 im Serum mit Tumorstadien und Prognose des hepatozellulären Karzinoms / Astrid Wendt". Berlin : Medizinische Fakultät Charité - Universitätsmedizin Berlin, 2020. http://d-nb.info/1212435109/34.

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McKeeman, G. C. "The measurement of circulation soluble vascular endothelial growth factor receptor-1 (sFlt-1)". Thesis, Queen's University Belfast, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.273085.

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Luque, Yosu. "Rôle de l'épithélium et de l'endothélium rénal au cours des glomérulopathies expérimentales. Etude des glomérulonéphrites inflammatoires et des glomérulopathies toxique et hypertensive". Electronic Thesis or Diss., Paris 6, 2016. https://accesdistant.sorbonne-universite.fr/login?url=https://theses-intra.sorbonne-universite.fr/2016PA066394.pdf.

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Les maladies glomérulaires sont une des principales causes d'insuffisance rénale terminale de nos jours et constituent un problème de santé publique. Le concept classique dans les glomérulopathies accorde à l'agression systémique immune, toxique ou hypertensive le rôle principal dans la formation des lésions glomérulaires. L'hypothèse développée dans ce manuscrit est que épithélium et endothélium, deux composants principaux du parenchyme rénal sont des acteurs majeurs dans la formation des lésions glomérulaires. Trois modèles expérimentaux de glomérulopathie (inflammatoire, toxique et hypertensive) chez la souris nous ont permis d'étudier une voie de signalisation épithéliale γC/JAK/STAT classiquement décrite dans les cellules immunitaires et le système de réponse à l'hypoxie endothéliale afin d'étayer cette hypothèse. Après avoir discuté le rôle principal classiquement attribué aux lymphocytes T dans le modèle anti-membrane basale glomérulaire, un modèle animal de glomérulonéphrite inflammatoire, nous avons démontré le rôle protecteur de la chaîne γ commune (γC) glomérulaire et de sa protéine d'aval STAT5 dans le podocyte au cours du modèle anti-MBG et de la néphropathie à l'adriamycine. Enfin, nous avons étudié le rôle protecteur de EPAS1 (HIF-2α), une sous-unité régulatrice du complexe HIF, dans l'endothélium au cours des lésions glomérulaires hypertensives. Au total, ce travail met en évidence le rôle majeur de l'épithélium et l'endothélium rénal, étroitement liés, dans la formation des lésions glomérulaires. Le parenchyme rénal représente un acteur à part entière dans la physiopathologie de ces lésions comme le montrent les travaux sur les systèmes γC/STAT5 et HIF
Glomerular diseases are a leading cause of kidney failure and represent a public health problem. Classically, systemic effectors such as the immune system, drug toxicity or hypertension are thought to be the main drivers of glomerular diseases. The hypothesis developed in this manuscript is that epithelium and endothelium, the two main components of the renal parenchyma, are major players in the formation of glomerular lesions. Three experimental models of glomerular disease (inflammatory, toxic and hypertensive) in mice allowed us to study epithelial γC / JAK / STAT signaling classically described in immune cells and the endothelial hypoxia inducible system in order to support this hypothesis. After discussing the main role traditionally assigned to T cells in the anti- glomerular basement membrane model, an animal model of inflammatory glomerulonephritis, we demonstrated the protective role of the glomerular interleukin common γ chain (γC) receptor and its dependent podocyte-specific STAT5 during the anti-GBM model and adriamycin nephropathy. We then showed the protective role of endothelial EPAS1 (HIF-2α), a regulatory subunit of HIF complex in focal segmental glomerulosclerosis (FSGS) induced by angiotensin II. In total, this work highlights the important role of the closely linked renal epithelium and endothelium in the formation of glomerular lesions using three experimental models of glomerular diseases. The renal parenchyma is a full player in the pathophysiology of these lesions as shown by the works studying γC / JAK / STAT and HIF systems

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Johansson, Anders. "Search for biomarkers in ALS and Parkinson's Disease positron emission tomography and cerebrospinal fluid studies /". Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis : Univeritetsbiblioteket [distributör], 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-102040.

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38

Ghosh, Rajarshi. "Transcriptional Regulation of VEGFA by Unfolded Protein Response Signaling Pathway". eScholarship@UMMS, 2010. https://escholarship.umassmed.edu/gsbs_diss/469.

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The endoplasmic reticulum is the primary organelle in the cell which has the responsibility of properly folding proteins belonging to the secretory pathway. Secretory proteins are essential for a variety of functions within the body like metabolism, growth and survival. Hence, proper folding of the proteins in the ER is absolutely essential to maintain cellular and body function. The environment of the ER is substantially different from that of the cytoplasm and is primed essentially to provide the optimum conditions to fold newly synthesized polypeptides following translation by the ribosomes in the cytoplasm and on the surface of the ER. In order for secretory proteins to fold properly, ER homeostasis must be maintained. ER homeostasis is defined by the dynamic balance between the ER protein load and the ER capacity to process this load. The optimum environment of the ER, or ER homeostasis, can be perturbed by pathological processes such as hypoxia, glucose deprivation, viral infections, environmental toxins, inflammatory cytokines, and mutant protein expression, as well as by physiological processes such as aging. Disruption of ER homeostasis causes accumulation of unfolded and misfolded proteins in the ER. This condition is referred to as ER stress. Cells cope with ER stress by activating the unfolded protein response (UPR). The UPR is initiated by three ER transmembrane proteins: Inositol requiring 1 (IRE1), PKR-like ER kinase, and activating transcription factor 6 (ATF6). These three master regulators sense and interpret protein folding conditions in the ER and translate this information across the ER membrane to activate downstream effectors, spliced XBP1, phosphorylated eIF2α and ATF4, and cleaved active ATF6 respectively. These effectors have two distinct outputs, homeostatic and apoptotic. Homeostatic outputs are adaptive responses that function to attenuate ER stress and restore ER homeostasis. These responses include the attenuation of protein translation to reduce ER workload and prevent further accumulation of unfolded proteins, upregulation of molecular chaperones and protein processing enzymes to enhance the ER folding activity, and the increase in ER-associated degradation (ERAD) components to promote clearance of unfolded proteins. When ER stress reaches a point where the cells cannot tolerate the load of unfolded proteins any more, apoptosis sets in. One of the major secretory proteins in mammals, vascular endothelial growth factor VEGF, is essential for either normal or pathological angiogenesis (blood vessel development). VEGFA is the primary member of this family which is expressed in all endothelial cells and is responsible for sprouting and invasion of blood vessels into the interstitium and thus helps in supplying nutrients and oxygen to growing cells. Recent studies have indicated that cells suffering from insufficient blood supply experience ER stress. The ER needs energy and oxygen for the folding process, thus nutrient deprivation (low ATP production) and hypoxia caused by insufficient blood supply leads to inefficient protein folding and ER stress in cells, especially in cancer cells that grow and spread rapidly. This condition also occurs in the development of the mammalian placenta. The placenta is an essential tissue characterized by a lot of blood vessels. It is responsible for the exchange of nutrients and growth factors between maternal and fetal blood vessels and hence is essential for survival of the embryo. Nutrient deprivation and hypoxia stimulate the production of VEGFA and other angiogenic factors, leading to protection against ischaemic injury in both cancer cells as well as the developing placenta. In this dissertation, we report that the three master regulators of the UPR, IRE1α, PERK and ATF6α, mediate transcriptional regulation of VEGFA under ER stress in cancer cells. Inactivation of any of the three master regulators leads to attenuation of VEGFA expression under ER stress. We show that IRE1α is able to regulate VEGFA through its downstream transcription factor XBP1 which activates the VEGFA promoter. IRE1α mediated VEGFA regulation is also essential for normal development of labyrinthine trophoblast cells in the placenta. ATF6α also regulates VEGFA via its promoter. PERK is able to activate VEGFA by preferential activation of its downstream effector, ATF4, which binds intron 1 of the VEGFA gene. Thus our work reveals a twopronged differential regulatory action of the UPR sensors on VEGFA gene expression. This work suggests that a fully active UPR is essential for VEGFA upregulation under ER stress. All three regulators are required in cancer cells for normal VEGFA expression. This tight regulation of VEGFA by the UPR presents a wonderful opportunity for therapeutic intervention into angiogenic growth of tumors.

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39

Ismail, Hodan. "Vascular endothelial growth factor and angiopoietin-1 regulate leukocyte adhesion to endothelial cells through the nuclear receptor Nur77". Thesis, McGill University, 2012. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=107844.

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Vascular endothelial growth factor (VEGF) and angiopoietin 1 (Ang-1) are critical regulators of angiogenesis. Additionally, both have been found to participate in inflammatory processes: VEGF as a pro-inflammatory and Ang-1 as an anti-inflammatory mediator. Nur77 is a member of a family of orphan receptors (NR4A) that includes Nurr1 and Nor1 and plays a role in regulating vascular inflammation; however, this has yet to be fully understood. The aim of this study was to evaluate whether Nur77 expression in endothelial cells (ECs) serves as a negative feedback mechanism designed to inhibit NFkappaB induction, dampen VEGF-induced E-selectin and VCAM1 expression and enhanced leukocyte adhesion to ECs, and mediate the suppression of EC activation induced by Ang-1 treatment.Treatment of human umbilical vein endothelial cells (HUVECs) with either VEGF or Ang-1 significantly and transiently induced Nur77 expression and enhanced PKD-dependent HDAC7 phosphorylation and mobilization from the nucleus to the cytosol. HUVECs transduced with adenoviruses expressing mutated HDAC7 or a dominant-negative PKD1 inhibited VEGF-, but not Ang-1-, induced Nur77 expression. Inhibition of PI3K and ERK1/2 resulted in the suppression of Ang-1-induced Nur77 expression whereas the inhibition of JNK resulted in significantly greater induction of Nur77 by Ang-1. NFκB binding activity and gel shift assays revealed that Nur77 inhibits VEGF-induced NFκB activity. Overexpression of Nur77 showed titre-dependent upregulation of IκBα mRNA and protein expressions that was not evident in HUVECs transduced with viruses expressing a dominant-negative form of Nur77 (Ad-dnNur77). Functionally, Nur77 was found to suppress VEGF-induced mRNA and protein expressions of the adhesion molecules E-selectin and VCAM1. Importantly, the role of Nur77 in cytokine-induced leukocyte adhesion to ECs was examined. Adherence of U937 cells to HUVECs activated by VEGF was suppressed by overexpressing Nur77 whereas the loss of Nur77 by siRNA interference resulted in augmentation of adhesion. Interestingly, Ang1 was able to dampen VEGF-induced monocyte adhesion to HUVEC monolayers. I conclude that Nur77 plays an important role in providing a negative feedback mechanism designed to attenuate VEGF-induced pro-inflammatory responses through selective inhibition of NFκB activation. Furthermore, Nur77, in part, may be vital to the Ang-1 anti-inflammatory response.
Les facteurs de croissance endothélials vasculaires (VEGF) et l'angiopoïétine 1 (Ang-1) sont de régulateurs essentiels de l'angiogénèse. En outre, tous les deux ont été découverts pour leur participation dans le processus d'inflammation: VEGF comme pro-infammatoire et Ang-1 comme médiateur anti-inflammatoire. Nur77 est un membre de la famille des récepteurs orphelins (NR4A) qui comprend Nurr1 and Nor1 et jouent un rôle dans la régulation de l'inflammation vasculaire; toutefois cela n'est pas encore totalement compris. Le but de cette étude était d'évaluer si l'expression de Nur77 dans les cellules endothéliales (ECs) sert de mécanisme de rétroaction négatif conçu pour inhiber l'induction de NFκB en réduisant l'expression de la E-selectin et de VCAM1 induite par VEGF, ainsi que l'adhésion des leucocytes aux ECs, et pour agir en médiateur de la suppression de l'activation des ECs induite par le traitement avec Ang-1. Le traitement des cellules endothéliales humaines de la veine ombilicale (HUVECs) soit avec VEGF ou Ang-1 induit de façon significative et transitoire l'expression de Nur77 et augmente la Phosphorylation de HDAC7 PKD dépendante et la mobilisation du noyau vers le cytosol. Les HUVECs transduits avec les adénovirus exprimant HDAC7 muté ou un dominant négatif PKD1 inhibent VEGF, mais pas l'expression de Nur77 induit par Ang-1. L'inhibition de la PI3K et de ERK1/2 aboutit à la suppression de l'expression de Nur77 induit par Ang-1 alors que l'inhibition de JNK résulte de façon significative en une plus grande induction de Nur77 par Ang-1. L'essai d'activité de liaison de NFκB ainsi que celui du gel de retardation révèlent que Nur77 inhibe l'activité de NFκB induit par VEGF. La surexpression de Nur77 a montré une sur-régulation dépendante de la titration de l'ARNm et de l'expression protéique de IκBα, pas évidente avec les HUVECs transduites avec les virus exprimant la forme dominante négative de Nur77 (Ad-dnNur77). J'ai trouvé que Nur77 réprimait l'ARNm et l'expression protéique de E-selectin and VCAM1 induit par VEGF. De façon importante, le rôle de Nur77 dans l'adhésion des leucocytes aux ECs induits par les cytokines a été examiné. L'adhérence des cellules U937 aux HUVECs activées par VEGF était réprimée par la surexpression de Nur77 alors que la perte de Nur77 par l'ARNsi d'interférence résulte dans une augmentation de l'adhésion. De manière intéressante, Ang-1 était capable d'amortir l'adhésion aux monocouches de HUVECs induite par VEGF. Je conclus que Nur77 joue un rôle important en fournissant un mécanisme de rétroaction négatif conçu pour atténuer la réponse pro-infammatoire induite par VEGF à travers l'inhibition sélective de l'activation de NFκB. Par ailleurs Nur77 en partie, peut être vital pour les réponses anti-inflammatoires d'Ang-1.

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Vuorela, Piia. "Vascular endothelial growth factor, its receptors, and the Tie receptor in normal and complicated pregnancy". Helsinki : University of Helsinki, 2000. http://ethesis.helsinki.fi/julkaisut/laa/kliin/vk/vuorela/.

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Nourse, Marilyn Brower. "Control of endothelial cell differentiation and proliferation for vascular tissue engineering /". Thesis, Connect to this title online; UW restricted, 2007. http://hdl.handle.net/1773/7998.

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42

Cardoso, Camila Lopes. "Análise morfométrica e molecular da alveolite induzida em ratos com diferentes modalidades de tratamento". Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/25/25132/tde-27052009-102252/.

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Abstract (sommario):

A alveolite é uma complicação pós-operatória de carácter inflamatório que acomete alvéolos de dentes recém-extraídos. A incidência dessa complicação varia de 1 a 4% e pode chegar a 30%. O objetivo deste estudo foi analisar os mecanismos biológicos envolvidos no processo de reparo de alvéolos intencionalmente infectados, em ratos; comparar diferentes modalidades de tratamento e correlacionar os resultados encontrados através de duas análises (microscópica e molecular). Foram utilizados 84 ratos, divididos nos grupos: I: alvéolo não infectado; II: alvéolo infectado sem nenhum tratamento; III: alvéolo infectado tratado com irrigação de solução de iodeto de sódio a 2% e peróxido de hidrogênio a 3% na proporção de 1:1; e IV: alvéolo infectado submetido à curetagem, irrigação com soro fisiológico e preenchimento com uma pasta à base de metronidazol. Os animais foram eutanasiados aos 6, 15 e 28 dias pós-operatório. Foi realizada a análise quantitativa da expressão de genes envolvidos no processo de reparo [colágeno tipo I (COL-I), fator de crescimento do endotélio vascular (VEGF), osteocalcina (OCN), fosfatase alcalina (ALP), runt-related transcription factor 2 (RUNX2) e fator de necrose tumoral alfa (TNF-\'alfa\')], através da RealTimePCR, correlacionando sua expressão com as características microscópicas observadas qualitativa e quantitativamente. Com base nos resultados da análise microscópica e molecular, podemos concluir que os marcadores RUNX2, OCN e TNF-\'alfa\' podem ser usados como indicadores para avaliar a neoformação óssea e a quantidade de infiltrado inflamatório em alveolite. Os marcadores ALP e VEGF não representaram adequadamente o que se observou microscopicamente. Embora o tratamento da alveolite com a pasta à base de metronidazol promova maior densidade de neoformação óssea aos 28 dias, não há diferenças entre os tratamentos.
Dry socket is an inflammatory postoperative complication that undertakes sockets of recently extracted teeth. The incidence of such complication varies from 1 to 4% and might reach up to 30%. The objective of this study was to analyze the biological mechanisms involved in the repair process of intentionally infected sockets in mice; compare different treatment conditions and correlate the results of two different analysis (microscopic and molecular). 84 mice were used in this study, divided according the following groups: I: uninfected socket; II: infected socket without any treatment; III: infected socket treated with irrigation of 2% sodium iodide and 3% hydrogen peroxide solution at 1:1 proportion; and IV: infected socket submitted to curettage, physiological saline solution irrigation and fulfillment with metronidazole base paste. The animals were killed at a postoperative period of 6, 15 and 28 days. A quantitative analysis was performed using a RealTimePCR to evaluate the genes expression involved [Collagen Type I (COL-I), vascular endothelial growth factor (VEGF), osteocalcin (OCN), alkaline phosphatase (ALP), runt-related transcription factor 2 (RUNX2) and tumor necrosis factor-alpha (TNF-\'alpha\')], in the repair process, correlating its expression with the microscopic characteristics observed in both qualitative and quantitative manner. Based in the results of the microscopic and molecular analysis, it can be concluded that the RUNX2, OCN and TNF-\'alpha\' markers can be used as indicators to evaluate the dry socket bone neoformation and inflammatory infiltrate quantity. The ALP and VEGF markers did not represented appropriately what was observed microscopically. Although the dry socket treatment with metronidazole base paste promotes an increase in the bone neoformation density at 28 days, no difference was found among the treatments.

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Inoue, Mayumi. "Oxidized LDL regulates vascular endothelial growth factor expression in human macrophages and endothelial cells through activation of peroxisome proliferator-activated receptor-γ". Kyoto University, 2003. http://hdl.handle.net/2433/148671.

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Li, Xiaobo. "PHYSICAL INTERACTIONS BETWEEN NEUROPILIN AND VEGFRS, INTEGRINS IN REGULATING ENDOTHELIAL CELL FUNCTIONS". UKnowledge, 2015. http://uknowledge.uky.edu/biochem_etds/23.

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The neuropilin (Nrp) family consists of multifunctional cell surface receptors with critical roles in a number of different cell and tissue types. A core aspect of Nrp function is ligand-dependent cellular adhesion and migration, where it controls the multistep process of cellular motility through integration of ligand binding, receptor coupling and signaling via the coordinated action of its extracellular and intracellular domains. While Nrp regulates cellular adhesion and motility in the cardiovascular and nervous systems under physiological conditions, the emerging pathological role of Nrp in tumor cell migration and metastasis has been identified and provides motivation for continued efforts toward developing Nrp inhibitors. At the molecular level, the role of Nrp in adhesion and migration is intimately connected to the control of adhesive interactions and cytoskeletal reorganization. The adhesive “interactome” for Nrp draws much attention because of its lack of enzymatic activity and inability to transduce signals on its own. It is an active area of research and is still expanding dramatically. Nrp has been well defined as a co-receptor for vascular endothelial growth factor receptor (VEGFR)/vascular endothelial growth factor (VEGF) signaling through enhancing receptor-ligand interaction in angiogenesis. Here, we contribute to this concept through characterization in more biochemical detail about Nrp-1/VEGF physical interactions. VEGF has been shown to compete with Sema3 for binding to Nrp-1 b1 ligand binding pocket. This competition fine-tunes VEGF-induced angiogenesis. Our data provides a molecular mechanism for high affinity Sema3F binding to Nrp-1 in the b1 domain. As to the VEGFR-independent function, Nrp/integrin association has been demonstrated. The functional integration has been shown for Nrp/integrin in angiogenic sprouting. Both proteins are highly expressed in endothelial tip cells to mediate endothelial cell migration during angiogenesis and knockdown of either one in mice leads to embryonic lethality due to similar defects in vascular development. To identify the structure and function correlation, we characterized in more detail about Nrp-1/integrin physical interactions with biochemical and cell-based assays. Through an integrated approach of biochemical, molecular and cellular methods, we defined the direct physical interactions between Nrp-1 and integrins. We have also extended this work to demonstrate the functional importance and contribution of the interactions in integrin-mediated cell adhesion on extracellular matrix (ECM) in angiogenesis and platelet function during wound healing and provide a molecular basis for the integration of Nrps/integrins in cell migration, adhesion to ECM, breast cancer initiation and breast cancer stem cell fate determination.

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Zabihi, Sheller. "Fetal Outcome in Experimental Diabetic Pregnancy". Doctoral thesis, Uppsala University, Department of Medical Cell Biology, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-8739.

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Women with pregestational diabetes have a 2-5 fold increased risk of giving birth to malformed babies compared with non-diabetic women. Diabetes-induced oxidative stress in maternal and embryonic tissues has been implicated in the teratogenic process. The malformations are likely to be induced before the seventh week of pregnancy, when the yolk sac is partly responsible for the transfer of metabolites to the embryo, and the uterine blood flow to the implantation site determines the net amount of nutrients available to the conceptus. We aimed to evaluate the effect on embryogenesis caused by a diabetes-induced disturbance in yolk sac morphology, uterine blood flow or altered maternal antioxidative status in conjunction with a varied severity of the maternal diabetic state.

We investigated to which extent maternal diabetes with or without folic acid (FA) supplementation affects mRNA levels and protein distribution of ROS scavenging enzymes (SOD, CAT, GPX), vascular endothelial growth factor-A (Vegf-A), folate binding protein-1 (Folbp-1), and apoptosis associated proteins (Bax, Bcl-2, Caspase-3) in the yolk sacs of rat embryos on gestational days 10 and 11. We found that maternal diabetes impairs, and that FA supplementation restores, yolk sac vessel morphology, and that maternal diabetes is associated with increased apoptotic rate in embryos and yolk sacs, as well as impaired SOD gene expression. We assessed uterine blood flow with a laser-Doppler-flow-meter and found increased blood flow to implantation sites of diabetic rats compared with controls. Furthermore, resorbed and malformed offspring showed increased and decreased blood flow to their implantation sites, respectively. In mice with genetically altered CuZnSOD levels, maternal diabetes increased embryonic dysmorphogenesis irrespective of CuZnSOD expression. We thus found the maternal diabetic state to be a major determinant of diabetic embryopathy and that the CuZnSOD status exerts a partial protection for the embryo in diabetic pregnancy.

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Chan, Gallant Kar Lun. "Molecular studies of the vascular endothelial growth factor (Vegf-A) and VEGF-receptor (Flk-1) genes of grass carp /". access full-text access abstract and table of contents, 2005. http://libweb.cityu.edu.hk/cgi-bin/ezdb/thesis.pl?mphil-bch-b19887668a.pdf.

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Thesis (M.Phil.)--City University of Hong Kong, 2005.
"Submitted to Department of Biology and Chemistry in partial fulfillment of the requirements for the degree of Master of Philosophy" Includes bibliographical references (leaves 124-141)

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Kubo, Hajime. "Involvement of Vascular Endothelial Growth Factor Receptor-3 in maintenance of integrity of entothelial cell lining during tumor angiogenesis". Kyoto University, 2000. http://hdl.handle.net/2433/151420.

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Wang, Shiyang. "The role of TRKB receptors in regulation of coronary microvascular endothelial cell angiogenesis /". Access full-text from WCMC, 2008. http://proquest.umi.com/pqdweb?did=1543605071&sid=5&Fmt=2&clientId=8424&RQT=309&VName=PQD.

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Wang, Amanda Cyphers. "Common Signaling Elements in Response Pathways Activated by the Endothelial Survival Factors VEGF and Insulin". Thesis, Virginia Tech, 2008. http://hdl.handle.net/10919/36205.

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Damage to the vasculature is a common occurrence in diabetes mellitus. At the cellular level, dysfunction of vascular endothelial cells is often associated with diabetic conditions. Multiple agents maintain the endothelium, including vascular endothelial growth factor (VEGF), an endothelial cell mitogen/survival factor, and insulin, which has anti-apoptotic effects on endothelial cells in addition to regulating glucose homeostasis. Insulin and VEGF, upon activating their respective tyrosine kinase receptors, can engage the PI3-kinase/Akt, MAPK, and PLC-γ/PKC pathways. Thus, crosstalk between VEGF and insulin signaling may occur at numerous points. Our objectives were twofold: 1) to characterize the combined effects of insulin and VEGF on downstream elements, and 2) to determine the ability of signaling intermediates principally associated with either insulin or VEGF signaling to interact directly. After treatment with VEGF, insulin, or both, cells expressing both VEGF receptor-2 (KDR) and the insulin receptor were immunoprecipitated for total Akt and PLC-γ. Isolates from cells stimulated with both ligands demonstrated activation of PLC-γ and Akt that was less than additive over fifteen minutes. Conversely, cells pretreated with advanced glycation end products showed increased Akt phosphorylation. The effect of insulin on VEGF bioactivity was also measured by PLC-γ-mediated hydrolysis of phosphatidylinositol. These studies suggested suppressed VEGF activity in the presence of insulin. To examine direct signaling interactions, recombinant reagents capable of selective binding (via SH2 domains) to phosphorylated receptors were generated. Overall results showed relatively unaffected VEGF activity in the presence of insulin; however, this relationship is likely altered within the diabetic state.
Master of Science

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Roos, Kelly. "The effect of sunitinib on neuroblastoma and glioblastoma cell growth". University of the Western Cape, 2020. http://hdl.handle.net/11394/7952.

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Magister Scientiae (Medical Bioscience) - MSc(MBS)
Cancer is a global health catastrophe, with neuroblastoma, the most common solid childhood tumor, and glioblastoma, a deadly brain tumor, being aggressive and unresponsive to current treatment modalities. These tumors are known to utilize uncontrollable cell proliferative capabilities as a mechanism for tumor survival. Therefore, malignant cell growth can be mitigated by targeting the essential proteins that regulate cell growth, such as receptor tyrosine kinases (RTKs). Under normal physiological conditions, RTKs bind with varying affinity to mitogenic stimuli such as growth factors such as vascular endothelial growth factor (VEGF) and platelet-derived growth factor (PDGF) which, in turn, leads to receptor phosphorylation and activation.

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Tesi sul tema "Vascular endothelial growth factor-receptor 2"

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