• BMB Reports
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• v.39 no.5
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• pp.469-478
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• 2006

Vascular endothelial growth factor (VEGF)-A, a major regulator for angiogenesis, binds and activates two tyrosine kinase receptors, VEGFR1 (Flt-1) and VEGFR2 (KDR/Flk-1). These receptors regulate physiological as well as pathological angiogenesis. VEGFR2 has strong tyrosine kinase activity, and transduces the major signals for angiogenesis. However, unlike other representative tyrosine kinase receptors which use the Ras pathway, VEGFR2 mostly uses the Phospholipase-$C{\gamma}$-Protein kinase-C pathway to activate MAP-kinase and DNA synthesis. VEGFR2 is a direct signal transducer for pathological angiogenesis including cancer and diabetic retinopathy, thus, VEGFR2 itself and the signaling appear to be critical targets for the suppression of these diseases. VEGFR1 plays dual role, a negative role in angiogenesis in the embryo most likely by trapping VEGF-A, and a positive role in adulthood in a tyrosine kinase-dependent manner. VEGFR1 is expressed not only in endothelial cells but also in macrophage-lineage cells, and promotes tumor growth, metastasis, and inflammation. Furthermore, a soluble form of VEGFR1 was found to be present at abnormally high levels in the serum of preeclampsia patients, and induces proteinurea and renal dysfunction. Therefore, VEGFR1 is also an important target in the treatment of human diseases. Recently, the VEGFR2-specific ligand VEGF-E (Orf-VEGF) was extensively characterized. Interestingly, the activation of VEGFR2 via VEGF-E in vivo results in a strong angiogenic response in mice with minor side effects such as inflammation compared with VEGF-A, suggesting VEGF-E to be a novel material for pro-angiogenic therapy.

• 대한생식의학회:학술대회논문집
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• 2004.11a
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• pp.45-45
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• 2004

• Journal of Gastric Cancer
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• v.2 no.4
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• pp.195-199
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• 2002

Purpose: Angiogenesis is essential for tumor growth and metastasis and depends on the production of angiogenic factors that are secreted by tumor cells. Vascular endothelial growth factor (VEGF) is the most significant angiogenic factor and a selective mitogen for endothelial cells. VEGF, also known as the vascular permeability factor, acts on endothelial cells to increase microvascular permeability and directly stimulate the growth of new blood vessels. Several studies have reported that the expression of VEGF is correlated with hematogenous recurrence via angiogenesis in gastric carcinomas. This research evaluated the relationship between the expression of VEGF and hepatic and peritoneal recurrence in gastric carcinomas. Materials and Methods: Thirty specimens resected from patients with primary gastric carcinomas who had undergone curative resections were divided into three group: Group I, early gastric carcinomas without recurrence; Group II, advanced gastric carcinomas with hepatic recurrence; and Group III, advanced gastric carcinomas with peritoneal recurrence. The expression of VEGF and the density of the microvessel count were examined using immunohistochemistry. Results: 1) The expression of VEGF in Group II and Group III ($63.2\pm\24.3\%$) was stronger than that in Group I ($7\pm\4.2\%$). The expression of VEGF in Group II ($76.5\pm\13.2\%$) was stronger than that of the Group III ($50\pm\14.2\%$) (P<0.05). 2) The microvessel count in Group II ($49.9\pm14.5$) was more than that in Group I ($8.6\pm2.6$) and Group III ($29.1\pm18.1$) (P<0.05). 3) The microvessel count was increased significantly with increasing the expression of VEGF. Conclusions: The expression of VEGF is associated with advanced stomach cancer and hepatic recurrence has a higher expression of VEGF than peritoneal recurrence with neovascularization. Thus the expression of VEGF can be considered to be a useful indicator of recurrence in gastric carcinoma and especially in hepatic recurrence.

• Journal of Korean Neurosurgical Society
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• v.30 no.6
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• pp.683-687
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• 2001

Objective : Angiogenesis, the proliferation of capillary endothelial cells, is a vital component in the development, progression, and metastasis of many human tumors. Vascular endothelial growth factor(VEGF) is an endothelial cell-specific mitogen and induces angiogenesis and vascular permeability. The features of glioblastoma, distinct from low grade astrocytomas, are the presence of necroses and vascular endothelial proliferation. In this study, we investigated VEGF expression in the different grades of astrocytomas and determined whether VEGF expression correlates with development of glioblastoma and progression of astrocytomas. Patients and Methods : Forty seven patients with astrocytic tumors(24 males and 23 females), aged 3 to 65 years, were evaluated. Immunohistochemical staining was carried out using labelled streptavidin biotin method and primary antibody was a antirabbit polyclonal Ab against N-terminus region of VEGF165(Oncogene research product, MA, USA). Immunoreactivity(IR) was classified into no IR(absent or a trace of stain), moderate IR and intense IR by level of staining amount and intensity. Results : Six pilocytic astrocytomas showed 3 no IR and 3 moderate IR, 10 astrocytomas showed 2 no IR, 6 moderate IR and 2 intense IR, 12 anaplastic astrocytomas showed I no IR, 7 moderate IR and 4 intense IR and 19 glioblastomas showed 1 no IR, 11 moderate IR and 7 intense IR. Immunoreactivity was significantly different between low and high grade of tumors but there was no significant difference between anaplastic astrocytomas and glioblastomas. Gemistocytic tumor cells represented the predominent VEGF-immunoreactive cell types, as compared with compactly-arranged small tumor cells. In glioblastomas VEGF IR was observed in both perinecrotic and vital tumor areas. Conclusion : VEGF seems to be a important angiogenic factor in anaplastic astrocytomas and glioblastomas and VEGF expression may contribute to neovascularization of human astrocytomas.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.6
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• pp.3851-3854
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• 2013

Objective: To explore changes in the serum tumor makers, hypoxia-inducible factor-$1{\alpha}$ (HIF-$1{\alpha}$) and vascular endothelial growth factor (VEGF) level and their relations in patients with non-small cell lung cancer (NSCLC) before and after intervention. Materials and Methods: Forty patients with NSCLC and 40 healthy individuals undergoing physical examination in our hospital provided the observation and control groups. HIF-$1{\alpha}$ and VEGF levels in serum were detected by enzyme-linked immuno-sorbent assay (ELISA) in the observation group before and after intervention and in control group on the day of physical examination, along with serum carcino-embryonic antigen (CEA), neuron-speci ic enolase (NSE) and squamous cell carcinoma antigen (SCC) levels in the observation group with a fully automatic biochemical analyzer. Clinical effects and improvement of life quality in the observation group were also evaluated. Results: The total effective rate and improvement of life quality after treatment in observation group were 30.0% and 32.5%, respectively. Serum HIF-$1{\alpha}$ and VEGF levels in the control group were lower than that in observation group (p<0.01), but remarkably elevatedafter intervention (p<0.01). In addition, serum CEA, NSE and SCC levels were apparently lowered by treatment (p<0.01). Serum HIF-$1{\alpha}$ demonstrated a positive relation with VEGF level (p<0.01) and was inversely related with CEA, NSE and SCC levels (p<0.01). Conclusions: Significant correlations exist between marked increase of serum HIF-$1{\alpha}$ and VEGF levels and decrease of indexes related to hematological tumor markers in NSCLC patients after intervention.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.5
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• pp.1677-1682
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• 2015

Cancer progression is attained by uncontrolled cell division and metastasis. Increase in tumor size triggers different vascular channel formation to address cell nutritional demands. These channels are responsible for transferring of nutrients and gaseous to the cancer cells. Cancer vascularization is regulated by numerous factors including vascular endothelial growth factors (VEGFs). These factors play an important role during embryonic development. Members included in this group are VEGFA, VEGFB, VEGFC, PIGF and VEGFD which markedly influence cellular growth and apoptosis. Being freely diffusible these proteins act in both autocrine and paracrine fashions. In this review, genetic characterization these molecules and their putative role in cancer staging has been elaborated. Prognostic significance of these molecules along with different stages of cancer has also been summarized. Brief outline of ongoing efforts to target hot spot target sites against these VEGFs and their cognate limitations for therapeutic implications are also highlighted.

• The Korean Journal of Physiology and Pharmacology
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• v.24 no.5
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• pp.423-431
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• 2020

This study aimed to evaluate the effect of curcumin on brain hypoxic-ischemic (HI) damage in neonatal rats and whether the phosphoinositide 3-kinase (PI3K)/Akt/vascular endothelial growth factor (VEGF) signaling pathway is involved. Brain HI damage models were established in neonatal rats, which received the following treatments: curcumin by intraperitoneal injection before injury, insulin-like growth factor 1 (IGF-1) by subcutaneous injection after injury, and VEGF by intracerebroventricular injection after injury. This was followed by neurological evaluation, hemodynamic measurements, histopathological assessment, TUNEL assay, flow cytometry, and western blotting to assess the expression of p-PI3K, PI3K, p-Akt, Akt, and VEGF. Compared with rats that underwent sham operation, rats with brain HI damage showed remarkably increased neurological deficits, reduced right blood flow volume, elevated blood viscosity and haematocrit, and aggravated cell damage and apoptosis; these injuries were significantly improved by curcumin pretreatment. Meanwhile, brain HI damage induced the overexpression of p-PI3K, p-Akt, and VEGF, while curcumin pretreatment inhibited the expression of these proteins. In addition, IGF-1 treatment rescued the curcumin-induced down-regulated expression of p-PI3K, p-Akt, and VEGF, and VEGF overexpression counteracted the inhibitory effect of curcumin on brain HI damage. Overall, pretreatment with curcumin protected against brain HI damage by targeting VEGF via the PI3K/Akt signaling pathway in neonatal rats.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.28 no.2
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• pp.147-154
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• 2002

Genistein that is a component of soy has been reported to have a protective effect on the carcinogenesis of various tumors and to inhibit the growth of a wide variety of tumor cell in vitro. Angiogenesis is an essential process for the carcinogenesis, growth, invasion and metastasis of cancer and genistein has been suggested to act as natural anti-angiogenic agent. The purpose of this study was to evaluate the effects of genistein on the vascular endothelial growth factor (VEGF) expression in hamster buccal pouch oral carcinogenesis model induced by 9, 10-dimethyl 1,2-benzanthracene (DMBA). Experimental group that were supplied with 0.1mg/day genistein were sacrificed by time schedules and routinely processed for immunohistochemical examination of VEGF. In genistein treated group, carcinogenesis was retarded with respect to the acanthosis, hyperkeratosis, and epithelial dysplasia. Immunohistochemical study showed that the VEGF protein of genistein group was less expressed than that of the control group. (p<0.05) Thus, it is postulated that genistein has chemopreventive effect on the oral carcinogenesis, and this chemopreventive effect, at least partly, is originated from the anti-angiogenic effect of genistein

• Animal Bioscience
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• v.34 no.4
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• pp.533-538
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• 2021

Objective: Pluripotent stem cell-derived lymphatic endothelial cells (LECs) show great promise in their therapeutic application in the field of regenerative medicine related to lymphatic vessels. We tested the approach of forced differentiation of mouse embryonal stem cells into LECs using biodegradable poly lactic-co-glycolic acid (PLGA) nanospheres in conjugation with growth factors (vascular endothelial growth factors [VEGF-A and VEGF-C]). Methods: We evaluated the practical use of heparin-conjugated PLGA nanoparticles (molecular weight ~15,000) in conjugation with VEGF-A/C, embryoid body (EB) formation, and LEC differentiation using immunofluorescence staining followed by quantification and quantitative real-time polymerase chain reaction analysis. Results: We showed that formation and differentiation of EB with VEGF-A/C-conjugated PLGA nanospheres, compared to direct supplementation of VEGF-A/C to the EB differentiation media, greatly improved yield of LYVE1(+) LECs. Our analyses revealed that the enhanced potential of LEC differentiation using VEGF-A/C-conjugated PLGA nanospheres was mediated by elevation of expression of the genes that are important for lymphatic vessel formation. Conclusion: Together, we not only established an improved protocol for LEC differentiation using PLGA nanospheres but also provided a platform technology for the mechanistic study of LEC development in mammals.

• Nutrition Research and Practice
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• v.15 no.4
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• pp.444-455
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• 2021

BACKGROUND/OBJECTIVES: Adipocytes undergo angiogenesis to receive nutrients and oxygen needed for adipocyte' growth and differentiation. No study relating quercetin with angiogenesis in adipocytes exists. Therefore, this study investigated the role of quercetin on adipogenesis in 3T3-L1 cells, acting through matrix metalloproteinases (MMPs). MATERIALS/METHODS: After proliferating preadipocytes into adipocytes, various quercetin concentrations were added to adipocytes, and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays were performed to evaluate cell proliferation. Glycerol-3-phosphate dehydrogenase (GPDH) activity was investigated as an indicator of fat accumulation. The mRNA expressions of transcription factors related to adipocyte differentiation, CCAAT/enhancer-binding proteins (C/EBPs), peroxisomal proliferatoractivated receptors (PPAR)-γ, and adipocyte protein 2 (aP2), were investigated. The mRNA expressions of proteins related to angiogenesis, vascular endothelial growth factor (VEGF)-α, vascular endothelial growth factor receptor (VEGFR)-2, MMP-2, and MMP-9, were investigated. Enzyme activities and concentrations of MMP-2 and MMP-9 were also measured. RESULTS: Quercetin treatment suppressed fat accumulation and the expressions of adipocyte differentiation-related genes (C/EBPα, C/EBPβ, PPAR-γ, and aP2) in a concentration-dependent manner in 3T3-L1 cells. Quercetin treatments reduced the mRNA expressions of VEGF-α, VEGFR-2, MMP-2, and MMP-9 in 3T3-L1 cells. The activities and concentrations of MMP-2 and MMP-9 were also decreased significantly as the concentration of quercetin increased. CONCLUSIONS: The results confirm that quercetin inhibits adipose tissue differentiation and fat accumulation in 3T3-L1 cells, which could occur through inhibition of the angiogenesis process related to MMPs.